United
States
Prevention,
Pesticides
EPA
738­
R­
04­
003
Environmental
Protection
and
Toxic
Substances
September
2003
Agency
(
7508C)

Reregistration
Eligibility
Decision
for
Oxadiazon
ii
CERTIFIED
MAIL
Dear
Registrant:

This
is
to
inform
you
that
the
Environmental
Protection
Agency
(
hereafter
referred
to
as
EPA
or
the
Agency)
has
completed
its
review
of
the
available
data
and
public
comments
received
related
to
the
risk
assessment
for
the
oxadiazole
pesticide,
oxadiazon
(
Ronstar
®
)
.
Based
on
its
review,
EPA
has
identified
risk
mitigation
measures
that
the
Agency
believes
are
necessary
to
address
the
human
health
and
environmental
risks
associated
with
the
current
use
of
oxadiazon.
The
EPA
is
now
publishing
its
reregistration
eligibility
and
risk
management
decisions
for
the
current
uses
of
oxadiazon,
and
its
associated
human
health
and
environmental
risks.
The
enclosed
"
Reregistration
Eligibility
Decision
for
Oxadiazon,"
which
was
approved
on
September
15,
2003,
contains
the
Agency's
decision
on
the
individual
chemical
oxadiazon.

A
Notice
of
Availability
for
this
Reregistration
Eligibility
Decision
(
RED)
for
oxadiazon
is
published
in
the
Federal
Register.
To
obtain
a
copy
of
the
RED
document,
please
contact
the
OPP
Public
Regulatory
Docket
(
7502C),
US
EPA,
Ariel
Rios
Building,
1200
Pennsylvania
Avenue
NW,
Washington,
DC
20460,
telephone
(
703)
305­
5805.
Electronic
copies
of
the
RED
and
all
supporting
documents
are
available
on
the
Internet.
See
http://
www.
epa.
gov/
pesticides.

This
document
and
the
process
used
to
develop
it
are
the
result
of
a
pilot
process
to
facilitate
greater
public
involvement
and
participation
in
the
reregistration
and/
or
tolerance
reassessment
decisions
for
pesticides.
As
part
of
the
Agency's
effort
to
involve
the
public
in
the
implementation
of
the
Food
Quality
Protection
Act
of
1996
(
FQPA),
the
Agency
is
undertaking
a
special
effort
to
maintain
open
public
dockets
and
to
engage
the
public
in
the
reregistration
and
tolerance
reassessment
processes
for
these
chemicals.
The
human
health
and
environmental
risk
assessments
were
placed
in
the
public
docket
and
an
invitation
for
public
comment
was
announced
in
the
Federal
Register
on
February
19,
2003.

Please
note
that
the
oxadiazon
risk
assessments
and
the
attached
RED
concern
only
this
particular
chemical.
Oxadiazon
is
a
member
of
the
oxadiazole
class
of
herbicides.
While
current
data
are
limited,
EPA
has
evidence
that
compounds
within
a
class
may
share
a
common
mechanism
of
toxicity.
At
this
time,
the
Agency
does
not
have
sufficient
data
concerning
common
mechanism
issues
to
determine
whether
or
not
oxadiazon
shares
a
common
mechanism
of
toxicity
with
other
substances,
including
other
oxadiazoles
or
iii
other
probable
human
carcinogens.
Therefore,
for
the
purposes
of
this
risk
assessment,
the
Agency
has
assumed
that
oxadiazon
does
not
share
a
common
mechanism
of
toxicity
with
any
other
chemicals.

End­
use
product
labels
should
be
revised
by
the
manufacturer
to
adopt
the
changes
set
forth
in
Section
V
of
this
document.
Instructions
for
registrants
on
submitting
revised
labeling
and
the
time
frame
established
to
do
so
can
be
found
in
Section
V
of
this
document.

If
you
have
questions
on
this
document
or
the
proposed
label
changes,
please
contact
the
Special
Review
and
Reregistration
Division
representative,
Mark
Seaton,
at
(
703)
306­
0469.
For
questions
about
product
reregistration
and/
or
the
Product
DCI
that
accompanies
this
document,
please
contact
Bentley
Gregg
at
(
703)
308­
8178.

Betty
Shackleford,
Acting
Director
Special
Review
and
Reregistration
Division
Attachment
iv
Reregistration
Eligibility
Decision
for
Oxadiazon
List
B
Case
2485
v
Table
of
Contents
Glossary
of
Terms
and
Abbreviations
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vi
Oxadiazon
Reregistration
Eligibility
Decision
Team
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viii
Executive
Summary
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1
I.
Introduction
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4
II.
Chemical
Overview
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6
A.
Chemical
Identification
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6
B.
Use
Profile
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7
C.
Estimated
Usage
of
Pesticide
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7
D.
Regulatory
History
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8
III.
Summary
of
Oxadiazon
Risk
Assessment
.
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9
A.
Human
Health
Risk
Assessment
.
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9
1.
Toxicity
of
Oxadiazon
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9
2.
Dose
Response
Assessment
and
Toxicity
Endpoints
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11
3.
FQPA
Considerations
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13
4.
Dietary
Risk
from
Drinking
Water
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14
5.
Residential
and
Other
Non­
occupational
Post­
application
Risks
.
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16
6.
Occupational
Risk
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18
7.
Incident
Data
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25
B.
Environmental
Risk
Assessment
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25
vi
1.
Environmental
Fate
and
Transport
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25
2.
Water
Resources
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26
3.
Ecological
Risk
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27
4.
Endangered
Species
Risk
Assessment
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35
IV.
Risk
Management,
Reregistration
and
Tolerance
Reassessment
Decision
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36
A.
Determination
of
Reregistration
Eligibility
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36
B.
Tolerance
Reassessment
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36
C.
Regulatory
Position
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37
1.
FQPA
and
Aggregate
Risk
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37
2.
Endocrine
Disruptor
Effects
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37
3.
Cumulative
Risks
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37
4.
Benefits
Assessment
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38
D.
Tolerance
Summary
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38
E.
Human
Health
Risk
Mitigation
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38
1.
Dietary
(
Drinking
Water)
Risk
Mitigation
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38
2.
Non­
occupational
Post­
application
Risk
Mitigation
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40
3.
Occupational
Risk
Mitigation
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41
4.
Inhalation
Toxicity
and
Exposure
Uncertainties
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43
F.
Environmental
Risk
Mitigation
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43
1.
Terrestrial
Organism
Risk
Mitigation
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43
2.
Aquatic
Organism
Risk
Mitigation
.
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44
G.
Other
Labeling
Requirements
.
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45
1.
Endangered
Species
Statement
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45
2.
Spray
Drift
Management
.
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46
V.
Actions
Required
of
Registrants
.
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47
A.
Manufacturing
Use
Products
.
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48
1.
Additional
Generic
Data
Requirements
.
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48
vii
2.
Labeling
for
Manufacturing
Use
Products
.
.
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49
B.
End­
Use
Products
.
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49
1.
Additional
Product­
Specific
Data
Requirements
.
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49
2.
Labeling
for
End­
Use
Products
.
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49
C.
Labeling
Requirements
Summary
Table
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51
D.
Existing
Stocks
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56
viii
Glossary
of
Terms
and
Abbreviations
AGDCI
Agricultural
Data
Call­
In
ai
Active
Ingredient
aPAD
Acute
Population
Adjusted
Dose
AR
Anticipated
Residue
BCF
Bioconcentration
Factor
CFR
Code
of
Federal
Regulations
cPAD
Chronic
Population
Adjusted
Dose
CSF
Confidential
Statement
of
Formula
CSFII
USDA
Continuing
Surveys
for
Food
Intake
by
Individuals
DCI
Data
Call­
In
DEEM
Dietary
Exposure
Evaluation
Model
DFR
Dislodgeable
Foliar
Residue
DWLOC
Drinking
Water
Level
of
Comparison.

EC
Emulsifiable
Concentrate
Formulation
EEC
Estimated
Environmental
Concentration.

EP
End­
Use
Product
EPA
Environmental
Protection
Agency
FDA
Food
and
Drug
Administration
FIFRA
Federal
Insecticide,
Fungicide,
and
Rodenticide
Act
FFDCA
Federal
Food,
Drug,
and
Cosmetic
Act
FQPA
Food
Quality
Protection
Act
FOB
Functional
Observation
Battery
G
Granular
Formulation
GENEEC
Tier
I
Surface
Water
Computer
Model
GLN
Guideline
Number
HAFT
Highest
Average
Field
Trial
IR
Index
Reservoir
LC50
Median
Lethal
Concentration.
A
statistically
derived
concentration
of
a
substance
that
can
be
expected
to
cause
death
in
50%
of
test
animals.
It
is
usually
expressed
as
the
weight
of
substance
per
weight
or
volume
of
water,
air
or
feed,
e.
g.,
mg/
l,
mg/
kg
or
ppm.
ix
LD50
Median
Lethal
Dose.
A
statistically
derived
single
dose
that
can
be
expected
to
cause
death
in
50%
of
the
test
animals
when
administered
by
the
route
indicated
(
oral,
dermal,
inhalation).
It
is
expressed
as
a
weight
of
substance
per
unit
weight
of
animal,
e.
g.,
mg/
kg.

LOC
Level
of
Concern
LOD
Limit
of
Detection
LOAEL
Lowest
Observed
Adverse
Effect
Level
MATC
Maximum
Acceptable
Toxicant
Concentration

g/
g
Micrograms
Per
Gram

g/
L
Micrograms
Per
Liter
mg/
kg/
day
Milligram
Per
Kilogram
Per
Day
mg/
L
Milligrams
Per
Liter
MOE
Margin
of
Exposure
MUP
Manufacturing­
Use
Product
MRID
Master
Record
Identification
(
number).
EPA's
system
of
recording
and
tracking
studies
submitted.

NA
Not
Applicable
NAWQA
USGS
National
Water
Quality
Assessment
NPDES
National
Pollutant
Discharge
Elimination
System
NR
Not
Required
NOAEL
No
Observed
Adverse
Effect
Level
OP
Organophosphate
OPP
EPA
Office
of
Pesticide
Programs
OPPTS
EPA
Office
of
Prevention,
Pesticides
and
Toxic
Substances
PCA
Percent
Crop
Area
PAD
Population
Adjusted
Dose
PDP
USDA
Pesticide
Data
Program
PHED
Pesticide
Handler's
Exposure
Data
PHI
Preharvest
Interval
ppb
Parts
Per
Billion
PPE
Personal
Protective
Equipment
ppm
Parts
Per
Million
PRZM/

EXAMS
Tier
II
Surface
Water
Computer
Model
Q1*
The
Carcinogenic
Potential
of
a
Compound,
Quantified
by
the
EPA's
Cancer
Risk
Model
RAC
Raw
Agriculture
Commodity
RED
Reregistration
Eligibility
Decision
x
REI
Restricted
Entry
Interval
RfD
Reference
Dose
RQ
Risk
Quotient
SCI­
GROW
Tier
I
Ground
Water
Computer
Model
SAP
Science
Advisory
Panel
SF
Safety
Factor
SLC
Single
Layer
Clothing
SLN
Special
Local
Need
(
Registrations
Under
Section
24(
c)
of
FIFRA)

TGAI
Technical
Grade
Active
Ingredient
TRR
Total
Radioactive
Residue
USDA
United
States
Department
of
Agriculture
USGS
United
States
Geological
Survey
UF
Uncertainty
Factor
UV
Ultraviolet
WPS
Worker
Protection
Standard
xi
Oxadiazon
Reregistration
Eligibility
Decision
Team
Office
of
Pesticide
Programs:

Biological
and
Economic
Analysis
Division
Stephen
Smearman
Economic
Analysis
Branch
William
Chism
Herbicide
and
Insecticide
Branch
Environmental
Fate
and
Effects
Division
Mike
Rexrode
Environmental
Risk
Branch
5
Jose
Melendez
Environmental
Risk
Branch
4
Faraque
Khan
Environmental
Risk
Branch
4
Health
Effects
Division
Nancy
McCarroll
Toxicology
Branch
1
Sheila
Piper
Chemistry
and
Exposure
Branch
1
Seyed
(
Nader)
Tadayon
Chemistry
and
Exposure
Branch
1
Ken
Dockter
Reregistration
Branch
2
Registration
Division
Joanne
Miller
Herbicide
Branch
Gene
Wilson
Herbicide
Branch
Special
Review
and
Reregistration
Division
Mark
Seaton
Reregistration
Branch
2
Tom
Myers
Reregistration
Branch
2
1
Executive
Summary
This
document
presents
the
Environmental
Protection
Agency's
(
the
Agency)
decision
regarding
the
reregistration
eligibility
of
the
registered
uses
of
oxadiazon.
The
Agency
made
its
reregistration
eligibility
determination
based
on
the
data
required
for
reregistration,
the
current
guidelines
for
conducting
acceptable
studies
to
generate
such
data,
and
published
scientific
literature.
The
Agency
has
found
that
currently
registered
uses
of
oxadiazon
are
eligible
for
reregistration,
provided
specified
changes
are
made
to
the
label.

Oxadiazon
is
a
herbicide
registered
for
use
on
golf
course
and
commercial
turf,
and
on
ornamental
plants
and
shrubs
by
horticultural
nurseries.
There
are
no
registered
homeowner
uses.
EPA
estimates
that
approximately
250,000
pounds
of
active
ingredient
are
used
annually,
about
80%
of
which
is
applied
to
golf
course
turf.

Overall
Risk
Summary
EPA's
human
health
risk
assessment
for
oxadiazon
suggests
dietary
(
drinking
water)
and
occupational
risks
of
concern.
Risk
estimates
based
on
refined
(
Tier
II)
models
indicate
a
chronic
cancer
risk
of
concern
from
exposure
to
drinking
water
from
surface
water
sources.
To
further
assess
the
risk
from
drinking
water
exposure,
the
Agency
is
requiring
the
registrant
to
submit
three
years
of
drinking
water
monitoring
data
collected
from
sites
determined
by
the
Agency
to
be
likely
to
result
in
upper­
bound
exposures.

In
addition,
there
is
a
cancer
risk
of
concern
for
handlers
who
mix/
load/
apply
wettable
powder
formulations.
To
mitigate
the
cancer
risk
to
handlers,
the
Agency
is
requiring
changes
to
packaging,
as
well
as
changes
to
the
required
personal
protective
equipment
for
handlers
who
mix/
load/
apply
wettable
powder
formulations.

The
ecological
risk
assessment
suggests
potential
chronic
risks
of
concern
to
aquatic
organisms
from
application
of
oxadiazon
at
the
maximum
application
rate
of
8
lbs
ai/
A/
year
to
golf
courses.
In
order
to
further
assess
the
risk
to
fish
and
invertebrates
from
oxadiazon
exposure,
the
Agency
is
requiring
that
the
registrant
submit
additional
early
stage
fish
toxicity
data
and
invertebrate
life
cycle
toxicity
data.

Dietary
Risk
Acute,
chronic
and
cancer
dietary
risk
from
food
are
not
of
concern
since
there
are
no
food
tolerances
and
no
registered
food
uses.
Acute
and
chronic
(
non­
cancer)
risks
from
oxadiazon
in
groundwater
and
surface
water
are
also
not
of
concern.
Cancer
risks
from
surface
water
are
potentially
of
concern
for
the
general
population
based
on
modeled
estimates
of
environmental
concentrations
of
oxadiazon
in
surface
water
from
use
on
golf
courses.
To
address
potential
drinking
water
risks
associated
with
estimated
surface
water
concentrations
resulting
from
the
use
of
oxadiazon
on
golf
course
turf,
the
registrant
has
agreed
to
reduce
the
maximum
annual
application
rate
at
6
lbs
ai/
A,
with
the
exception
that
areas
heavily
infested
with
weeds
may
be
treated
with
up
to
8
lbs
ai/
A.
The
registrant
has
agreed
to
provide
additional
water
monitoring
data
to
refine
exposure
estimates.
2
Occupational
Risks
Risks
for
occupational
handlers
of
oxadiazon
are
of
concern.
Exposures
of
concern
include
mixing/
loading/
applying
wettable
powder
formulations.
To
mitigate
the
cancer
risk
to
handlers,
the
registrant
has
agreed
that
wettable
powder
formulations
of
oxadiazon
be
packaged
in
water­
soluble
packaging.
In
addition,
wettable­
powder
product
labels
will
require
that
handlers
wear
chemical­
resistant
gloves
in
addition
to
long
pants
and
a
long­
sleeved
shirt
during
mixing/
loading/
applying
activities.

Occupational
post­
application
scenarios
assessed
for
oxadiazon
include
golf
course
and
sod
farm
workers
engaged
in
turf
maintenance.
There
are
no
risks
of
concern
from
occupational
post­
application
exposure
scenarios.

Residential
Risk
There
were
no
exposure
scenarios
of
concern
for
residential
risk.

Ecological
Risks
Oxidiazon
use
on
golf
course
turf
is
of
concern
given
the
maximum
application
rates
for
turf
and
the
likelihood
of
golf
course
runoff
to
move
toward
surface
water.
Acute
risks
for
birds,
mammals,
fish,
aquatic
invertebrates
and
aquatic
plants
at
the
typical
application
rates
for
golf
course
turf
are
not
of
concern.
Chronic
risks
are
not
a
concern
for
birds
or
mammals,
but
are
potentially
of
concern
for
aquatic
organisms
at
the
maximum
application
rate
of
6
lbs
ai/
A/
year
for
turf.
In
order
to
further
assess
the
risk
to
fish
and
invertebrates
from
oxadiazon
exposure,
the
Agency
is
requiring
that
the
registrant
submit
additional
toxicity
data
including
early­
stage
estuarine
fish
studies
and
life
cycle
estuarine/
marine
invertebrate
studies.
Also,
enhanced
toxicity
through
exposure
to
high
levels
of
solar
radiation
may
increase
risk
to
aquatic
organisms
that
inhabit
small,
shallow
water
bodies.
Therefore,
EPA
is
requiring
a
study
on
the
phototoxicity
of
oxadiazon
in
fathead
minnows.

Reregistration
Eligibility
Decision
As
required
under
Section
4(
g)(
2)(
A)
of
FIFRA,
the
Agency
has
completed
its
review
of
oxadiazonspecific
data,
and
has
determined
that
the
data
are
sufficient
to
support
reregistration
of
all
products
containing
oxadiazon
provided
that
certain
data
gaps
are
addressed,
the
risk
reduction
measures
outlined
in
this
document
are
adopted
and
labels
are
amended
to
implement
these
measures.
The
reviewed
data
were
sufficient
to
allow
the
Agency
to
determine
that
oxadiazon
can
be
used
without
resulting
in
unreasonable
adverse
effects
to
humans
and
the
environment.
The
Agency,
therefore,
finds
that
all
products
containing
oxadiazon
as
the
active
ingredient
are
eligible
for
reregistration,
provided
specified
changes
are
made
to
the
label.
Actions
needed
to
reregister
particular
products
are
addressed
in
Section
V
of
this
document
The
Agency
concludes
that
these
label
changes
address
the
current
risk
estimates
and
reflect
the
use
of
all
acceptable
data
available
at
this
time
together
with
uncertainty
factors
where
data
gaps
exist.
3
4
I.
Introduction
The
Federal
Insecticide,
Fungicide,
and
Rodenticide
Act
(
FIFRA)
was
amended
in
1988
to
accelerate
the
reregistration
of
products
with
active
ingredients
registered
prior
to
November
1,
1984.
The
amended
Act
calls
for
the
development
and
submission
of
data
to
support
the
reregistration
of
an
active
ingredient,
as
well
as
a
review
of
all
submitted
data
by
the
U.
S.
Environmental
Protection
Agency
(
referred
to
as
EPA
or
"
the
Agency").
Reregistration
involves
a
thorough
review
of
the
scientific
database
underlying
a
pesticide's
registration.
The
purpose
of
the
Agency's
review
is
to
reassess
the
potential
hazards
arising
from
the
currently
registered
uses
of
the
pesticide;
to
determine
the
need
for
additional
data
on
health
and
environmental
effects;
and
to
determine
whether
or
not
the
pesticide
meets
the
"
no
unreasonable
adverse
effects"
criteria
of
FIFRA.

On
August
3,
1996,
the
Food
Quality
Protection
Act
(
FQPA)
was
signed
into
law.
This
Act
amends
FIFRA
to
require
tolerance
reassessment
during
reregistration.
It
also
requires
that
by
2006,
EPA
must
review
all
tolerances
in
effect
on
the
day
before
the
date
of
the
enactment.
FQPA
also
amends
the
Federal
Food,
Drug,
and
Cosmetic
Act
(
FFDCA)
to
require
a
safety
finding
in
tolerance
reassessment
based
on
factors
including
an
assessment
of
cumulative
effects
of
chemicals
with
a
common
mechanism
of
toxicity.

With
respect
to
tolerances
for
oxadiazon,
there
have
been
no
active
food­
use
registrations
since
1991.
The
tolerance
for
rice
straw
was
revoked
as
of
the
July
1,
2001
revision
to
40
CFR
180.346.
In
a
confirmatory
letter
to
EPA,
dated
January
24,
2001,
the
registrant
maintained
its
previous
position
that
it
would
not
support
the
sixteen
remaining
oxadiazon
tolerances.
Therefore,
effective
April
24,
2003,
EPA
revoked
all
the
tolerances
in
40
CFR
180.346
for
the
combined
residues
of
the
herbicide
oxadiazon
and
its
metabolites
in
the
following
commodities:
in
or
on
milk;
cattle,
fat;
cattle,
meat;
cattle,
meat
byproducts;
goats,
fat;
goats,
meat;
goats,
meat
byproducts;
hogs,
fat;
hogs,
meat;
hogs,
meat
byproducts;
horses,
fat;
horses,
meat;
horses,
meat
byproducts;
sheep,
fat;
sheep,
meat;
and
sheep,
meat
byproducts.
In
addition,
because
EPA
determined
on
April
21,
2002
that
there
is
no
reasonable
expectation
of
finite
residues
of
oxadiazon
and
its
metabolites
in
or
on
meat,
milk,
poultry,
and
egg
commodities,
the
sixteen
associated
tolerances
for
livestock
commodities
were
considered
by
the
Agency
to
no
longer
be
needed
under
40
CFR
180.6(
a)(
3).
Therefore,
on
June
3,
2002,
the
Agency
considered
the
FQPA
safety
finding
to
be
met
and
counted
the
sixteen
oxadiazon
livestock
tolerances
as
reassessed.

Given
that
all
tolerances
for
oxadiazon
have
been
revoked,
this
pesticide
no
longer
falls
under
the
scope
of
FQPA.
As
such,
no
quantitative
aggregate
assessment
of
risk
from
dietary
and
residential
exposures
was
completed
as
part
of
the
reregistration
process.
EPA
has
evaluated
the
likelihood
of
concurrent
exposures
to
oxadiazon
for
the
general
population,
including
children.
Because
of
the
relatively
low
volume
of
use
of
oxadiazon
on
sites
other
than
golf
courses,
its
specialized
use
pattern,
and
its
relatively
high
cost,
concurrent
exposures
are
not
likely.

At
this
time,
the
Agency
has
not
made
a
decision
as
to
whether
oxadiazon
shares
a
common
mechanism
of
toxicity
with
other
oxadiazoles,
or
any
other
pesticide.
A
careful
evaluation
of
all
the
available
data
is
still
needed,
as
well
as
peer
review
by
the
FIFRA
Scientific
Advisory
Panel,
before
a
formal
decision
is
made.
Therefore,
for
the
purposes
of
this
risk
assessment,
the
Agency
has
assumed
that
oxadiazon
does
not
share
a
5
common
mechanism
of
toxicity
with
other
pesticides.
After
a
decision
is
made
regarding
common
mechanism
of
toxicity,
and
if
the
Agency
has
determined
that
a
cumulative
assessment
is
necessary,
the
Agency
will
address
any
outstanding
risk
concerns
at
that
time.

This
document
presents
the
Agency's
decision
regarding
the
reregistration
eligibility
of
the
registered
uses
of
oxadiazon,
including
the
consideration
of
risk
to
infants,
children
and
adults
for
any
potential
food,
drinking
water,
dermal,
inhalation
or
oral
exposures.
In
an
effort
to
simplify
the
RED,
the
information
presented
herein
is
summarized.
More
detailed
information
can
be
found
in
the
technical
supporting
documents
for
oxadiazon
referenced
in
this
RED.
The
revised
risk
assessments
and
related
addenda
are
not
included
in
this
document,
but
are
available
on
the
Agency's
web
page
at
www.
epa.
gov/
pesticides,
and
in
the
Public
Docket.

This
document
consists
of
six
sections.
Section
I
is
the
introduction.
Section
II
provides
a
profile
of
the
use
and
usage
of
oxadiazon,
and
its
regulatory
history.
Section
III
gives
an
overview
of
the
human
health
and
environmental
assessments,
based
on
the
data
available
to
the
Agency.
Section
IV
presents
the
reregistration
eligibility
and
risk
management
decisions.
Section
V
summarizes
the
necessary
label
changes
based
on
the
risk
mitigation
measures
outlined
in
Section
IV.
Finally,
the
Appendices
list
all
related
documents
and
how
to
access
them,
and
Data
Call­
In
(
DCI)
information.
6
II.
Chemical
Overview
A.
Chemical
Identification
°
Common
name:
Oxadiazon
°
Chemical
name:
[
2­
tert­
butyl­
4­(
2,4­
dichloro­
5­
isopropoxyphenyl)
­
2­
1,3,4­
oxadiazoline­
5­
one]

°
Empirical
formula:
C
15
H
18
Cl
2
N
2
O
3
°
CAS
Registry
No.:
19666­
30­
9
°
Case
number:
2485
°
OPP
Chemical
Code:
109001
°
Molecular
weight:
345.2
°
Trade
name:
Ronstar
°
Basic
manufacturer:
Bayer
Environmental
Science
Technical
oxadiazon
is
a
white,
crystalline
powder
with
a
melting
point
of
90

C.
Oxadiazon
is
stable
for
30
days
at
55

C,
and
is
stable
in
the
presence
of
aluminum,
iron
and
tin
powders
(
but
not
ferric
chloride).
The
water
solubility
of
oxadiazon
is
0.7
mg/
L
at
20

C.
Oxadiazon
has
a
vapor
pressure
of
7.76
x
10­
7
mm
Hg.

B.
Use
Profile
Oxadiazon
is
labeled
for
professional
use
only.
The
label
indicates
that
the
purchase,
storage
and
application
of
this
pesticide
are
limited
to
commercial
nursery,
turf
and
landscape
personnel.
The
product
is
7
not
available
to
homeowners.
The
following
is
information
on
the
currently
registered
uses
of
oxadiazon.
A
detailed
table
of
the
uses
of
oxadiazon
eligible
for
reregistration
is
contained
in
Appendix
A.

°
Type
of
Pesticide
and
Target
Pests:
Oxadiazon
is
a
pre­
emergent
or
early
post­
emergent
oxadiazole
herbicide
used
to
control
grassy
weeds
(
e.
g.,
goosegrass
and
crabgrass)
and
broadleaf
weeds
in
turf
and
ornamentals.
Oxadiazon
works
by
interfering
with
the
pathway
for
chlorophyll
production,
and
results
in
a
breakdown
of
plant
tissue
on
exposure
to
light.

°
Use
Sites:
Oxadiazon
is
registered
for
commercial
use
on
residential
turf
(
i.
e.,
apartment/
condominium
complexes,
parks,
athletic
fields,
playgrounds,
and
cemeteries)
and
on
golf
courses
(
predominant
use).
In
addition,
oxadiazon
is
used
on
sod
farms
and
on
conifer
nurseries
and
landscapes
(
i.
e.,
industrial
sites,
ornamental,
roadside
plantings,
woody,
ornamental
shrubs,
vines
and
trees,
and
herbaceous
ornamentals).
Oxadiazon
use
sites
are
classified
as
nonfood
sites
(
i.
e.,
primarily
golf
course
fairways),
residential
outdoor
use,
roadsides
and
nurseries.

°
Formulation
Types
Registered:
Oxadiazon
is
formulated
as
a
granular
(
predominant
formulation,
~
90%
of
total
use)
and
wettable
powder.

°
Method
and
Rates
of
Application
Equipment:
Granular
formulas
are
applied
using
mechanical
spreaders,
manual
spreaders
(
i.
e.,
belly
grinder,
push
type
spreader)
or
tractor­
drawn
spreaders.
Methods
of
application
associated
with
the
other
formulation
and
use­
patterns
of
oxadiazon
include:
groundboom,
rights­
of­
way
sprayer,
handgun
sprayer,
backpack
sprayer,
low
pressure
handwand,
high
pressure
handwand,
and
lawn
handgun.

Rates:
The
frequency
of
application
ranges
from
1
to
3
applications
per
season.
Oxadiazon
can
be
applied
at
a
minimum
single
application
rate
of
2.0
pounds
active
ingredient
per
acre
(
ai/
A)
up
to
a
maximum
single
application
rate
of
4.0
pounds
ai/
A
to
turf
and
ornamentals.
The
annual
maximum
application
rate
is
8
lbs
ai/
A/
year.

Use
Classification:
Not
classified.

C.
Estimated
Usage
of
Pesticide
Approximately
250,000
pounds
of
oxadiazon
are
applied
to
approximately
50,000
acres
annually.
Oxadiazon
is
used
primarily
in
southern
states
and
predominantly
on
golf
courses.
Table
1
summarizes
the
EPA's
best
available
estimates
for
the
pesticide
uses
of
oxadiazon.
These
estimates
are
derived
from
a
variety
of
published
and
proprietary
sources
available
to
the
Agency.

Table
1.
Oxadiazon
Usage
Summary
8
Crop
Lbs.
Active
Ingredient
Applied
(
Wtd.
Avg.)
1
Percent
Crop
Treated
(
Likely
Maximum)
Percent
Crop
Treated
(
Wtd.
Avg.)
1
Turf:

Golf
Courses
160,000
6%
3%

Landscape,
Rights­
of­
way,
Parks
28,000
­­­
­­­

Horticultural
Nurseries
56,000
­­­
­­­

1Wtd
Avg
(
weighted
average):
the
most
recent
years
and
more
reliable
data
are
weighted
more
heavily.

­­­:
missing
information
or
lack
of
confidence
in
the
data.

D.
Regulatory
History
Oxadiazon
was
registered
in
1978.
A
Phase
Four
generic
data
call­
in
(
DCI)
was
issued
in
May
of
1991.
Due
to
additional
data
required
under
FIFRA
as
amended
in
1988,
the
oxadiazon
registrant
decided
to
no
longer
support
food
uses
of
oxadiazon.
With
respect
to
tolerances
for
oxadiazon,
there
have
been
no
active
food­
use
registrations
since
1991.
The
tolerance
for
rice
straw
was
revoked
as
of
the
July
1,
2001
revision
to
40
CFR
180.346.
In
a
confirmatory
letter
to
EPA,
dated
January
24,
2001,
the
registrant
maintained
its
previous
position
that
it
would
not
support
the
sixteen
remaining
oxadiazon
tolerances.
Therefore,
effective
April
24,
2003,
EPA
revoked
all
the
tolerances
in
40
CFR
180.346
for
the
combined
residues
of
the
herbicide
oxadiazon
and
its
metabolites
in
the
following
commodities:
in
or
on
milk;
cattle,
fat;
cattle,
meat;
cattle,
meat
byproducts;
goats,
fat;
goats,
meat;
goats,
meat
byproducts;
hogs,
fat;
hogs,
meat;
hogs,
meat
byproducts;
horses,
fat;
horses,
meat;
horses,
meat
byproducts;
sheep,
fat;
sheep,
meat;
and
sheep,
meat
byproducts.
In
addition,
because
EPA
determined
on
April
21,
2002
that
there
is
no
reasonable
expectation
of
finite
residues
of
oxadiazon
and
its
metabolites
in
or
on
meat,
milk,
poultry,
and
egg
commodities,
the
sixteen
associated
tolerances
for
livestock
commodities
were
considered
by
the
Agency
to
no
longer
be
needed
under
40
CFR
180.6(
a)(
3).
Therefore,
on
June
3,
2002,
the
Agency
considered
the
FQPA
safety
finding
to
be
met
and
counted
the
sixteen
oxadiazon
livestock
tolerances
as
reassessed.
There
are
no
CODEX,
Canadian,
or
Mexican
tolerances
for
oxadiazon
residues.
9
III.
Summary
of
Oxadiazon
Risk
Assessments
A.
Human
Health
Risk
Assessment
1.
Toxicity
of
Oxadiazon
Details
of
the
hazard
assessment
of
oxadiazon
can
be
found
in
the
revised
Human
Health
Risk
Assessment
for
Oxadiazon,
dated
June
6,
2003
(
McCarroll,
2003).
Major
features
of
the
toxicology
profile
are
presented
below.
In
acute
studies,
oxadiazon
was
only
slightly
toxic
to
rats
and
rabbits.
In
rabbits,
oxadiazon
was
mildly
irritating
to
ocular
tissue
and
negligibly
irritating
to
the
skin,
and
in
guinea
pig
studies,
oxadiazon
was
not
a
dermal
sensitizer
(
Table
2).

Table
2.
Acute
Toxicity
Data
on
Oxadiazon
Guideline
No./
Study
Type
MRID
No.
Results
Toxicity
Category
870.1100
Acute
oral
toxicity
(
rat)
41866501
(
97.5%
a.
i.)
LD50
>
5000
mg/
kg

,

combined
IV
870.1200
Acute
dermal
toxicity
(
rabbit)
41866502
(
97.5%
a.
i.)
LD50
>
2000
mg/
kg,

,

combined
III
870.1300
Acute
inhalation
toxicity
(
rat)
41866503
(
93.7%
a.
i.)
LC50
>
1.94
mg/
L

,

combined
III
870.2400
Acute
eye
irritation
(
rabbit)
41866504
(
97.5%
a.
i.)
Mild
irritant
to
ocular
tissues
III
870.2500
Acute
dermal
irritation
(
rabbit)
41866505
(
97.5%
a.
i.)
Negligibly
irritating
to
skin
III
870.2600
Skin
sensitization
(
guinea
pig)
41230401
(
93.7%
a.
i.)
Not
a
dermal
sensitizer
(
Buehler
test)

­­

In
both
subchronic
and
chronic
studies,
the
major
target
organ
of
oxadiazon
toxicity
was
the
liver.
Effects
were
consistent
among
the
species
tested
(
rat,
dog,
mouse)
and
typically
included
enlarged
livers
along
with
increases
in
serum
clinical
chemistry
parameters
associated
with
hepatotoxicity
such
as
alkaline
phosphatase
and
serum
aspartate
or
alanine
aminotransferase.

Following
long­
term
dietary
administration,
oxadiazon
caused
an
increased
incidence
of
hepatocellular
adenoma
and
carcinoma
in
rats
and
mice.
Consistent
findings
were
reported
in
a
total
of
four
acceptable
10
studies
in
two
species
(
two
mouse
and
two
rat
studies).
A
third
mouse
study
was
unacceptable,
although
increased
hepatocellular
tumors
were
also
observed
in
mice
of
both
sexes.
A
classification
of
"
likely
to
be
carcinogenic
to
humans"
was
assigned
by
the
Cancer
Assessment
Review
Committee
(
CARC).
A
quantitative
risk
(
Q
1*)
of
7.11
x
10­
2
(
mg/
kg/
day)­
1
was
calculated
as
the
most
potent
unit
risk,
based
on
the
incidence
of
male
mouse
liver
adenoma
and/
or
carcinoma
combined
tumor
rates
in
the
ICR­
JCL
mouse.

In
a
special
submitted
mechanistic
study
in
rats
and
a
published
study
in
rats,
mice
and
dogs,
oxadiazon
induced
peroxisomal
proliferation
(
based
on
liver
enlargement,
peroxisomal
enzyme
induction
and
electron
microscopy)
after
a
14­
day
dietary
administration.
Some
peroxisomal
proliferator
compounds
are
known
to
be
liver
carcinogens,
but
the
Health
Effects
Division
Mechanism
of
Toxicity
Assessment
Review
Committee
(
MTARC)
concluded
that
there
is
insufficient
evidence
to
support
peroxisome
proliferation
as
a
mechanism
of
carcinogenicity
for
oxadiazon
due
to
insufficient
data
showing
hepatocellular
proliferation,
lack
of
concordance
between
the
enzyme
induction
dose­
response
and
tumor
formation,
and
an
unexplained
decrease
in
catalase,
which
is
normally
significantly
increased
by
peroxisomal
proliferator
compounds.

Oxadiazon
did
not
show
mutagenic
potential
in
any
in
vitro
assays
with
bacteria
(
S.
typhimurium
and
E.
coli)
or
mammalian
cells
(
TK
+/­
mouse
lymphoma
cells),
did
not
show
clastogenic
potential
in
the
in
vitro
Chinese
hamster
ovary
cell
chromosomal
aberration
assays
and
did
not
induce
unscheduled
DNA
synthesis
in
cultured
primary
rat
hepatocytes.
However,
a
dose­
related
increase
in
transformation
frequencies
was
observed
in
an
in
vitro
Syrian
hamster
kidney
BHK21
C13/
HRC1
cell
transformation
assay.

Significant
fetal
toxicity
(
fetal
loss
due
to
resorptions
and
post­
implantation
loss,
decreased
fetal
weight,
skeletal
variations)
was
observed
in
developmental
toxicity
studies
in
both
rats
and
rabbits.
These
fetal
effects
occurred
at
the
same
dose
levels
at
which
slight
maternal
toxicity
(
decreased
weight
gain/
weight
loss)
were
observed.
Offspring
survival
effects
were
also
observed
in
the
rat
two­
generation
reproduction
study.
No
toxicity
was
reported
at
the
lowest
dose
tested;
however,
in
the
range­
finding
phase
of
the
reproduction
study
at
higher
dose
levels,
fetal
and
neonatal
survival
were
also
sharply
reduced.
The
decreased
neonatal
survival
was
due
at
least
in
part
to
effects
on
lactation,
based
on
findings
of
inactive
mammary
glands
in
the
dams
at
necropsy.
Neonatal
loss
may
have
resulted
from
starvation
and
would,
therefore,
be
an
effect
of
direct
maternal
toxicity.
Inactivity
of
the
mammary
tissue
as
a
possible
effect
of
endocrine
disruption
was
considered
by
the
Hazard
Identification
Assessment
Review
Committee
(
HIARC)
but
was
not
found
to
be
likely
since
there
was
no
evidence
from
any
other
study
in
the
database
suggesting
endocrine
disruption.
No
fetal
malformations
were
observed
in
the
rat
or
rabbit
developmental
toxicity
studies;
however,
some
skeletal
variations
(
delayed
ossification,
asymmetric
pelvis)
were
reported.
The
above
findings
indicate
that
there
is
no
quantitative
evidence
of
increased
susceptibility
of
rats
or
rabbits
following
in
utero
or
postnatal
exposure
to
oxadiazon.

Neurotoxicity
studies
are
not
required
for
oxadiazon
because
no
clinical
signs
of
toxicity
suggestive
of
neurobehavioral
alterations
nor
evidence
of
neuropathological
effects
were
observed
in
any
of
the
available
toxicity
studies.
There
was
no
evidence
of
neurotoxicity
of
oxadiazon
in
the
rat
and
rabbit
developmental
toxicity
studies,
nor
in
the
rat
two­
generation
reproduction
toxicity
study.

Based
on
the
available
data,
the
Metabolism
Assessment
Review
Committee
(
MARC)
concluded
that
the
only
residue
of
concern
is
the
parent
compound,
oxadiazon,
because
major
degradation
products
would
only
be
minor
components
in
the
environment
and
are
not
likely
to
be
significantly
more
toxic
than
the
parent.
11
The
only
toxicity
data
gap
that
has
been
identified
at
this
time
is
a
28­
day
inhalation
study
(
OPPTS
No.
870.3465).
This
study
is
being
required
by
the
Agency
because
some
currently
registered
products
of
oxadiazon
include
spray
formulations
which
could
result
in
exposure
via
the
inhalation
route.

2.
Dose
Response
Assessment
and
Toxicity
Endpoints
The
HIARC
concluded
that
neither
an
acute
nor
a
chronic
reference
dose
(
RfD)
was
required
for
oxadiazon
because
there
are
no
food
or
feed
uses.
A
short­
term
oral
endpoint
was
selected
for
incidental
oral
exposure
in
children,
using
a
No
Observed
Adverse
Effect
Level
(
NOAEL)
of
12
mg/
kg/
day
based
on
a
statistically
significant
decrease
in
maternal
body
weight
gains
at
40
mg/
kg/
day
(
LOAEL)
in
a
developmental
study
in
rats
(
Table
3).
The
same
endpoint
was
selected
for
short­
term
and
intermediate
dermal
exposure.

In
the
absence
of
food
or
feed
uses,
HIARC
did
not
select
an
acute
RfD
for
oxadiazon.
In
order
to
estimate
acute
drinking
water
risk,
EPA
has
used
the
same
study
and
endpoint
described
above
for
short­
term
incidental
exposure.
For
the
acute
drinking
water
assessment
an
uncertainty
factor
of
100
was
applied,
based
on
a
10X
for
intraspecies
variation
and
a
10X
for
interspecies
extrapolation.
Therefore,
the
"
theoretical
acute
RfD"
would
be
0.12
mg/
kg/
day.
When
maternal
toxicity
can
be
attributed
to
a
single
dose
(
e.
g,
body
weight
loss
in
the
early
dosing
period),
the
developmental
studies
can
be
selected
for
the
acute
RfD,
the
short­
term
(
1­
7
days)
incidental
oral
exposure
and/
or
the
intermediate
(
7
days
to
several
months)
because
the
critical
effect
(
in
the
case
of
oxadiazon,
body
weight
loss
at
days
16­
20
which
was
possibly
due
to
resorption
of
fetuses)
occurred
during
the
treatment
period
which
encompasses
both
exposure
periods
of
concern.
It
is
reasonable
to
assume
that
effects
were
possibly
manifested
by
exposure
to
a
single
dose
and
the
resulting
body
weight
loss
did
not
become
apparent
until
after
7
days.

A
chronic
RfD
was
not
selected
by
HIARC
because
the
lack
of
food
or
feed
uses.
However,
for
the
purpose
of
assessing
potential
risks
from
drinking
water,
EPA
has
used
the
chronic/
oncogenicity
feeding
study.
For
the
chronic
drinking
water
assessment,
an
uncertainty
factor
of
100
was
applied
based
on
a
10x
factor
for
intraspecies
variation
and
a
10x
factor
for
interspecies
extrapolation.
This
chronic
oral
endpoint
was
based
on
increased
incidence
of
swollen
cells
in
the
central
lobe
of
the
livers
of
male
rats
observed
at
the
LOAEL
of
3.5
mg/
kg/
day.
The
NOAEL
in
this
study
was
0.36
mg/
kg/
day.
Therefore,
the
"
theoretical
chronic
RfD"
would
be
0.0036
mg/
kg/
day.
For
long­
term
dermal
exposure,
this
same
endpoint
was
selected.
The
HIARC
recommended
that
a
dermal
absorption
factor
of
9%
be
used
in
the
calculations,
based
on
a
dermal
penetration
study.

Due
to
a
lack
of
inhalation
studies,
the
HIARC
selected
an
endpoint
from
oral
studies
for
inhalation
risk
assessments.
For
short
and
intermediate­
term
inhalation
exposure,
the
same
oral
study
was
chosen
as
for
dermal
exposure
of
these
durations,
with
a
NOAEL
of
12
mg/
kg/
day.
The
same
chronic/
oncogenicity
feeding
study
in
rats
chosen
for
dermal
exposure
of
this
duration
was
selected
for
the
long­
term
inhalation
exposure,
with
a
NOAEL
of
0.36
mg/
kg/
day.
An
absorption
factor
of
100%
was
applied
for
inhalation
exposures.

A
level
of
concern,
referred
to
as
a
Margin
Of
Exposure
or
MOE,
of
100
for
occupational
and
residential
exposure
scenarios
was
calculated
using
a
10x
factor
for
intraspecies
variation
and
a
10x
factor
for
interspecies
extrapolation.
Because
the
effects
from
dermal
and
inhalation
exposure
are
the
same,
the
doses
for
these
routes
and
duration
were
combined.
Dermal
and
incidental
oral
exposures
for
toddlers
were
also
combined
to
reflect
a
total
exposure
burden.
12
Table
3:
Endpoints
for
Oxadiazon
Risk
Assessment
EXPOSURE
SCENARIO
DOSE
(
mg/
kg/
day)
ENDPOINT
STUDY
Incidental
Oral,
Short­
Term
and
Intermediate
Term
NOAEL=
12
Maternal
effects
Reduced
body
weight/
body
weight
gain
at
40
mg/
kg/
day
(
LOAEL).
Developmental
Toxicity
­
Rat
MRID
No.
40470202
Dermal,
Short­
Term
and
Intermediate­
Term
NOAEL=
12
Maternal
effects/
Developmental
effects
Reduced
body
weight/
body
weight
gain
at
40
mg/
kg/
day
(
LOAEL)
/
Increased
fetal
resorptions/
postimplantation
loss,
increased
incidence
of
incomplete
ossification
at
40
mg/
kg/
day
(
LOAEL).
For
this
risk
assessment,
the
dermal
absorption
rate
of
9%
is
applied.
Developmental
Toxicity
­
Rat
MRID
No.
40470202
Dermal,
Long­
Term
NOAEL=
0.36
Increased
centrilobular
swelling
in
male
livers
at
3.5
mg/
kg/
day
(
LOAEL).
For
this
risk
assessment,
the
dermal
absorption
rate
of
9%
is
applied.
Combined
Chronic
Feeding/

Oncogenicity
­
Rat
MRID
Nos.
40993401,
00149003/
00157780
Inhalation,
Short­
Term
and
Intermediate­
Term
NOAEL=
12
Maternal
effects/
Developmental
effects
Reduced
body
weight/
body
weight
gain
at
40
mg/
kg/
day
(
LOAEL)
/
Increased
fetal
resorptions/
postimplantation
loss,
increased
incidence
of
incomplete
ossification
at
40
mg/
kg/
day
(
LOAEL).
For
this
risk
assessment,
a
100%
absorption
rate
is
applied
Developmental
Toxicity
­
Rat
MRID
No.
40470202
Dietary,
Long­
term
NOAEL=
0.36
Increased
centrilobular
swelling
in
male
livers
at
3.5
mg/
kg/
day
(
LOAEL).
Combined
Chronic
Feeding/

Oncogenicity
­
Rat
MRID
Nos.
40993401,
00149003/
00157780
Inhalation,
Long­
Term
NOAEL=
0.36
Increased
centrilobular
swelling
in
male
livers
at
3.5
mg/
kg/
day
(
LOAEL).
A
100%
absorption
rate
applied.
Combined
Chronic
Feeding/

Oncogenicity
­
Rat
MRID
Nos.
40993401,
00149003/
00157780
Cancer
Q
1*
of
7.11
x
10­
2
(
mg/
kg/
day)­
1
Significant
increase
(
pair­
wise
and
trend,
p<
0.01)
in
liver
adenomas
and/
or
carcinomas
combined
in
males
at

9.3
mg/
kg/
day).
Combined
Chronic
Feeding/

Carcinogenicity
­
Mouse
MRID
Nos.
40993301
3.
FQPA
Considerations
On
August
3,
1996,
the
Food
Quality
Protection
Act
of
1996
(
FQPA)
was
signed
into
law.
This
Act
amends
FIFRA
to
require
tolerance
reassessment
during
reregistration.
With
respect
to
tolerances
for
oxadiazon,
there
have
been
no
active
food­
use
registrations
since
1991.
Effective
April
24,
2003,
EPA
revoked
all
the
tolerances
in
40
CFR
180.346
for
the
combined
residues
of
the
herbicide
oxadiazon
and
its
metabolites.
In
addition,
the
Agency
considered
the
FQPA
safety
finding
to
be
met
and
counted
the
sixteen
oxadiazon
livestock
tolerances
as
reassessed.

Given
that
there
are
no
remaining
food/
feed
uses
for
oxadiazon,
and
given
that
all
food
tolerances
have
been
revoked,
this
pesticide
no
longer
falls
under
the
scope
of
FQPA.
As
such,
no
quantitative
aggregate
13
assessment
of
risk
from
dietary
and
residential
was
conducted.
EPA
has
qualitatively
evaluated
the
likelihood
of
concurrent
exposures
from
different
sources
of
oxadiazon
for
the
general
population,
including
children.
Because
of
the
relatively
low
volume
of
oxadiazon
use
on
sites
other
than
golf
courses,
its
specialized
use
pattern,
and
its
relatively
high
cost,
concurrent
exposures
are
not
expected.

Only
15%
(
or
about
28,000
pounds)
of
the
oxadiazon
that
is
applied
each
year
is
used
on
parks,
landscapes,
rights­
of­
way,
etc.,
and
this
use
is
distributed
across
five
or
more
states.
An
even
smaller
portion
of
the
28,000
pounds
is
used
on
sites
where
people,
including
children
could
be
exposed,
such
as
parks.
Because
of
its
comparatively
high
cost,
oxadiazon
is
not
routinely
used
in
residential
lawn
care.
Furthermore,
the
exposure
assumption
in
both
the
residential
and
drinking
water
assessments
are
sufficiently
protective
to
account
for
the
unlikely
event
of
exposure
from
more
than
one
source.

With
respect
to
sensitivity
in
children,
there
is
no
evidence
of
either
a
qualitative
or
quantitative
increase
in
susceptibility
of
rats
or
rabbits
to
in
utero
and/
or
postnatal
oxadiazon
exposure.
Although
significant
fetal
toxicity
was
observed
in
developmental
toxicity
studies
in
both
rats
and
rabbits
(
i.
e.,
fetal
loss
due
to
resorptions
and
post­
implantation
loss)
and
in
a
two­
generation
reproduction
study
(
i.
e.,
reduced
neonatal
survival),
these
fetal/
neonatal
effects
occurred
at
the
same
doses
that
caused
maternal
toxicity.
It
is
also
likely
that
neonatal
losses
resulted
from
starvation
and
could,
thus,
be
a
possible
direct
maternal
toxic
effect.
Inactivity
of
the
mammary
tissue
as
a
possible
endocrine
disruption
effect
was
considered
but
was
found
to
be
unlikely
since
there
was
no
evidence
from
any
other
study
in
the
database
suggesting
endocrine
disruption.

4.
Dietary
Risk
from
Drinking
Water
Since
there
are
no
food/
feed
uses
of
oxadiazon
and
no
tolerances
exist,
dietary
risk
from
oxadiazon
can
only
result
through
exposure
in
drinking
water.
Drinking
water
exposure
to
pesticides
can
occur
through
ground
and
surface
water
contamination.
EPA
considers
acute,
chronic
non­
cancer,
and
chronic
cancer
drinking
water
risks
and
uses
modeling
and
monitoring
data,
if
available,
to
estimate
those
risks.
To
determine
the
maximum
contribution
from
water
allowed
in
the
diet,
EPA
first
looks
at
how
much
of
the
overall
allowable
risk
is
contributed
by
food
and
then
determines
a
"
drinking
water
level
of
comparison"
(
DWLOC)
to
ascertain
whether
or
not
modeled
or
monitored
concentrations
exceed
this
level.
In
the
case
of
oxadiazon,
there
is
no
contribution
from
food.
Estimated
environmental
concentrations
(
EECs)
that
are
above
the
corresponding
DWLOC
exceed
the
Agency's
level
of
concern.

Based
on
its
review
of
submitted
studies,
the
EPA
has
concluded
that
oxadiazon
would
be
stable
and
persistent
under
typical
terrestrial
environmental
conditions.
In
the
absence
of
measured
environmental
concentrations
of
oxadiazon
from
monitoring
studies,
and
based
on
environmental
fate
characteristics,
potential
oxadiazon
concentrations
in
unfinished
drinking
water
were
estimated
using
Tier
2
PRZM/
EXAMS
(
surface
water)
and
Tier
1
SCIGROW
(
ground
water)
models.
The
PRZM/
EXAMS
model
as
used
here
is
a
standard
turf
scenario
that
includes
a
two­
centimeter
layer
of
thatch,
and
is
referred
to
as
the
Florida
Turf
Scenario.

The
combined
("
linked")
PRZM/
EXAMS
model
is
typically
used
by
EPA
in
estimating
pesticide
concentrations
in
surface
waters.
The
PRZM
model
estimates
the
amount
of
pesticide
that
reaches
a
body
of
surface
water
as
a
result
of
runoff.
The
EXAMS
model
estimates
pesticide
concentrations
by
taking
into
account
different
mechanisms
for
dissipation,
weather
patterns,
and
periodic
application
of
pesticide,
for
14
several
years.
The
PRZM/
EXAMS
model
generates
concentration
estimates
of
acute
(
one
in
ten
year
peak
concentration),
non­
cancer
chronic
(
one
in
ten
year
mean
concentration)
and
chronic
cancer
(
36­
year
mean
concentration).

As
used
here,
the
PRZM/
EXAMS
estimates
of
pesticide
concentrations
in
surface
water
generated
by
this
linked
model
can
be
considered
to
be
upper­
bound
estimates.
Several
conservative
parameter
values
have
been
incorporated
into
the
mathematical
formulas,
including
a
calculated
factor
for
the
half­
life
of
oxadiazon
in
water.
The
Florida
Turf
Scenario
introduces
a
two­
inch
thatch
layer
as
an
intercept
to
incorporation
of
oxadiazon
with
soil
particles.
As
typically
applied,
oxadiazon
granules
are
watered
into
the
soil
surface,
thereby
mediating
the
potential
effects
of
the
thatch
layer.
Also,
an
assumption
in
the
current
model
is
that
oxadiazon
is
applied
as
a
wettable
powder
formulation
(
i.
e.,
applied
as
a
spray),
and
therefore
the
model
includes
a
value
for
spray
drift
into
water
bodies.

An
additional
conservative
parameter
incorporated
into
the
model
is
the
value
for
percent
crop
area
(
PCA).
The
term
PCA
refers
to
the
area
of
land
around
a
watershed
that
is
planted
with
crops
to
which
a
specific
pesticide
will
be
applied.
In
the
example
of
oxadiazon,
the
primary
application
site
is
golf
course
turf.
In
the
present
model,
a
PCA
value
of
94%
was
used
to
account
for
the
land
area
of
a
typical
golf
course
that
is
greens,
tees,
fairway
(
27%)
and
rough
(
67%).
The
EPA
makes
the
protective
assumption
that
94%
of
land
area
around
a
particular
watershed
might
possibly
be
made
up
of
golf
course,
and
that
100%
of
the
golf
courses
in
the
watershed
apply
oxadiazon
at
the
maximum
application
rate
and
frequency.
Registrants
have
submitted
a
GIS
analysis
suggesting
that
the
upper­
bound
limit
of
PCA
for
turf
(
including
golf
courses
and
other
recreational
turf)
in
south
Florida
is
substantially
less
than
94%.
Model­
derived
surface
water
EECs
and
DWLOCs
are
summarized
in
Table
4.

The
SCIGROW
model
is
typically
used
for
Tier
1
screening
purposes
for
pesticides
applied
to
soils.
The
SCIGROW
model
is
based
on
leaching
studies
conducted
in
sandy
soils
above
shallow
aquifers,
and
estimates
likely
groundwater
concentration.
In
areas
with
those
characteristics,
groundwater
is
particularly
vulnerable
to
contamination.
The
SCIGROW
model
estimated
environmental
concentration
for
oxadiazon
in
groundwater
is
0.59
ppb.

Table
4.
Surface
Water
DWLOC
and
EEC
Comparisons
Acute
DWLOC
(
ppb)
Acute
EEC
(
ppb)
Chronic
(
noncancer

DWLOC
(
ppb)
Chronic
(
noncancer

EEC
(
ppb)
Chronic
(
cancer)

DWLOC
(
ppb)
Chronic
(
cancer)

EEC
(
ppb)

Infants
(<
1
year)
1200
181
36
65
0.49
56
Children
(
1­
6
years)
1200
36
Females
(
13­
50
years)
3600
108
U.
S.
population
4200
126
Ground
Water
DWLOC
and
EEC
Comparisons
Table
4.
Surface
Water
DWLOC
and
EEC
Comparisons
15
Infants
(<
1
year)
1200
0.59
36
0.59
0.49
0.59
Children
(
1­
6
years)
1200
36
Females
(
13­
50
years)
3600
108
U.
S.
population
4200
126
a.
Acute
Drinking
Water
Risk
Acute
DWLOCs
were
calculated
for
oxadiazon
based
on
results
of
a
developmental
toxicity
study.
The
No
Observable
Adverse
Effect
Level
(
NOAEL)
was
12
mg/
kg/
day,
with
the
toxicity
endpoint
being
a
reduction
in
maternal
body
weight
gain
at
the
Lowest
Observable
Adverse
Effect
Level
(
LOAEL)
of
40
mg/
kg/
day.
The
rationale
for
selection
of
this
endpoint
is
provided
in
the
"
Dose
Response
and
Toxicity
Endpoint"
section
of
this
document.
Based
on
a
comparison
of
DWLOCs
to
the
corresponding
PRZM/
EXAMS
(
surface
water)
and
SCIGROW
(
groundwater)
estimates
(
EECs),
the
EECs
for
surface
water
(
181
ppb)
and
groundwater
(
0.59
ppb)
were
less
than
the
DWLOCs
calculated
for
all
populations
(
1200
­
4200
ppb)
and,
thus,
the
Agency
concludes
that
acute
exposure
to
residues
of
oxadiazon
in
surface
and
groundwater­
sourced
drinking
water
is
not
of
concern.

b.
Chronic
Drinking
Water
Risk
Chronic
DWLOCs
were
calculated
based
on
a
chronic
toxicity/
carcinogenicity
study.
The
NOAEL
was
0.36
mg/
kg/
day,
based
on
the
endpoint
of
centrilobular
swelling
in
male
rats,
observed
at
the
LOAEL
of
3.5
mg/
kg/
day.
The
rationale
for
selection
of
this
endpoint
is
provided
in
the
"
Dose
Response
and
Toxicity
Endpoint"
section
of
this
document.
Using
the
PRZM/
EXAMS
model
estimates,
the
EECs
for
surface
water
(
65
ppb)
were
higher
than
the
DWLOCs
calculated
for
infants
and
children
(
36
ppb)
(
Table
4)
and
thus,
potentially
of
concern.
The
chronic
ground
water
EEC
of
0.59
ppb
was
less
than
the
chronic
(
noncancer)
DWLOC
of
36
for
the
most
sensitive
subpopulations
(
children
less
than
1,
and
children
1­
6
years)
and
is
not
a
concern.

c.
Cancer
Drinking
Water
Risk
For
the
cancer
exposure
calculations,
the
Agency
used
multi­
year
mean
water
concentration
values.
The
DWLOC
cancer
is
the
concentration
in
drinking
water
that
results
in
a
negligible
cancer
risk
of
one
in
a
milion
(
1.0
x
10­
6).
The
cancer
ground
water
EEC
of
0.59
ppb
slightly
exceeds
the
DWLOC
of
0.49.
However,
given
the
protective
exposure
assumptions,
this
slight
exceedence
is
not
of
concern.
The
cancer
EEC
for
surface
water
(
56
ppb)
exceeds
the
cancer
DWLOC
(
0.49
ppb)
(
Table
4)
and
thus,
is
potentially
of
concern.

5.
Residential
and
Other
Non­
occupational
Post­
application
Risks
Since
oxadiazon
is
only
available
to
professional
turf,
landscape,
and
nursery
personnel,
there
are
no
residential
handler
scenarios.
Although
oxadiazon
is
not
available
for
homeowner
use,
the
Agency
has
determined
that
there
are
potential
postapplication
exposures
to
residents
entering
oxadiazon
treated
turf
and
16
lawns.
A
complete
discussion
of
potential
residential
exposures,
including
the
sources
of
exposure
data
and
toxicity
information
is
found
in
the
document
"
Revised
Occupational
and
Residential
Exposure
Assessment
and
Recommendations
for
the
Reregistration
Eligibility
Decision
Document
for
Oxadiazon"
dated
June
7,
2003
(
Tadayon,
2003)
on
the
Agency's
web
page
at
www.
epa.
gov/
pesticides,
and
in
the
Public
Docket.

The
scenarios
likely
to
result
in
postapplication
exposures
in
non­
occupational
situations
are
presented
below.
The
duration
of
postapplication
dermal
exposure
is
expected
to
be
either
short­
term
or
intermediateterm
based
on
oxadiazon
turf
residue
dissipation
data.
Oxadiazon
has
a
half­
life
on
turf
of
up
to
1.4
days
(
irrigated)
and
1.7
days
(
non­
irrigated)
after
spraying,
requiring
several
days
to
dissipate
to
non
detectable
levels
of
transferable
residues
(
MRID
#
435178­
01).
Because
the
label
prohibits
application
more
than
3
times
per
year,
and
even
with
the
slow
dissipation
rates,
it
is
not
expected
that
individual
residential
exposure
duration
would
exceed
30
days
in
duration.
Exposure
on
a
residential
lawn
would
diminish
continuously
with
time,
while
exposure
through
recreation
turf
contact
would
more
likely
be
random
intermittent
events
of
varying
doses,
all
less
than
the
dose
predicted
in
this
assessment.
Residential
postapplication
exposure
assessments
assume
that
residents
wear
the
following
attire:
short
sleeved
shirt,
short
pants,
shoes
and
socks,
and
no
gloves
or
respirator.
The
scenarios
likely
to
result
in
postapplication
exposures
are
as
follows:

°
dermal
postapplication
risks
to
adults
and
toddlers
when
entering
oxadiazon
treated
turf
and
lawns;

°
oral
postapplication
risks
to
toddlers
from
"
hand­
to­
mouth"
(
i.
e.,
ingestion
of
grass,
soil,
granular
pellets,
or
hand­
to­
mouth
contact)
exposure
when
reentering
lawns
treated
with
granular
and
wettable
powder
formulations.

Representative
turf
reentry
activities
include,
but
are
not
limited
to:

°
Adults
involved
in
a
low
exposure
activity,
such
as
golfing
or
walking
on
treated
turf.

°
Toddlers
involved
in
a
low
exposure
activity,
such
as
walking
on
treated
turf.

°
Adults
mowing
or
other
moderate
contact
activity,
for
1­
2
hours.

°
Adults
involved
in
a
high
exposure
activity,
such
as
heavy
yard
work
(
doses
similar
to
occupational
scenarios
for
cutting
and
harvesting
sod).

°
Toddlers
involved
in
high
exposure
activities
on
turf.

For
risk
assessment
purposes,
Margins
of
Exposure
(
MOEs)
compare
the
estimated
exposure
concentration
to
a
No
Observed
Adverse
Effect
Level
(
NOAEL)
from
an
animal
study.
In
the
case
of
oxadiazon,
the
Agency's
level
of
concern
for
residential
post­
application
risk
is
exceeded
if
MOEs
fall
below
100.
The
target
MOE
of
100
for
non­
occupational
exposure
scenarios
was
selected
based
on
the
uncertainty
factors
of
10x
for
intraspecies
variation
and
10x
for
interspecies
extrapolation.

The
registrant
submitted
a
study
on
turf­
transferable
residues
(
TTR)
in
response
to
an
occupational/
residential
exposure
Data
Call­
In,
and
in
support
of
oxadiazon
re­
registration
requirements.
Ronstar
®
50
WP
a
wettable
powder
product
containing
~
50
%
oxadiazon,
was
applied
to
turf
in
North
Carolina.
The
study
was
conducted
in
order
to
quantify
the
dermal
exposure
associated
with
re­
entry
onto
oxadiazon
treated
turf.
Ronstar
®
50
WP
which
is
labeled
for
use
on
dormant,
Bermuda
grass,
St.
Augustine
grass
and
Zoisia
turf
in
areas
such
as
fairways,
parks,
and
lawns
was
used
at
a
maximum
label
rate
of
3
.0
lb
ai/
A.
Two
different
exposure
scenarios
were
monitored:
17
­
Application
at
the
maximum
label
rate
followed
by
re­
entry
as
soon
as
the
turf
was
dry.

­
Application
followed
within
30
minutes
by
sprinkler
irrigation
of
1/
10
inch
of
water
with
re­
entry
occurring
as
soon
as
the
turf
is
dry.

Utilizing
the
transferable
residue
data
and
revised
residential
SOPs,
all
of
the
non­
cancer
risk
scenarios
developed
for
adults
and
children
had
short­
term
and
intermediate­
term
dermal
MOEs
greater
than
100.
The
cancer
risks
for
all
adult,
non­
occupational,
dermal,
post­
application
exposures
ranged
from
6
x
10­
6
to
8
x
10­
7
.
Although
the
estimated
cancer
risk
slightly
exceeds
the
Agency's
level
of
concern
(
1.0
x
10­
6),
that
estimate
is
conservative
given
that
the
risk
assessment
was
performed
with
a
spray
application,
whereas
approximately
90%
of
oxadiazon
is
applied
as
a
granular
formulation.
The
granule
size
for
a
typical
end­
use
product,
Ronstar
G,
is
20/
50
Mesh,
or
300­
850
microns.
In
all
instances,
the
granules
are
designed
to
fall
below
the
grass
canopy
and
into
the
thatch
layer.
If
used
according
to
label
directions,
it
is
unlikely
that
oxadiazon
granules
would
be
accessible
to
a
child
or
adult.
According
to
the
registrant,
for
best
results
oxadiazon
granules
should
be
watered­
in
as
soon
as
is
practical
following
application.
Watering­
in
the
granules
will
carry
them
further
into
the
thatch
layer,
and
will
further
decrease
the
likelihood
of
dermal
exposure.

Estimated
incidental
oral
short­
term
exposures
("
hand­
to­
mouth")
for
children
had
an
MOE
of
100
using
the
TTR
default
values
from
the
residential
SOP;
when
the
TTR
data
from
a
submitted
oxadiazon
study
were
used,
the
MOEs
were
240
and
90
for
irrigated
and
non­
irrigated
turf,
respectively.

MOEs
were
not
calculated
for
the
incidental
ingestion
of
oxadiazon
granules
because,
as
discussed
above,
the
very
small
granules
would
not
be
available
on
the
lawn
surface
and
thus
not
accessible
to
children.
It
is
thought,
therefore,
that
the
incidental
ingestion
of
granules
is
not
likely
to
be
a
cause
for
concern.

6.
Occupational
Risk
a.
Occupational
Toxicity
For
risk
assessment
purposes,
Margins
of
Exposure
(
MOEs)
compare
the
estimated
exposure
concentration
to
a
No
Observed
Adverse
Effect
Level
(
NOAEL)
from
an
animal
study.
In
the
case
of
oxadiazon,
the
Agency's
level
of
concern
for
occupational
risk
is
exceeded
if
MOEs
fall
below
100.
The
target
MOE
of
100
for
occupational
exposure
scenarios
was
selected
based
on
the
uncertainty
factors
of
10x
for
intraspecies
variation
and
10x
for
interspecies
extrapolation.
The
short­
term
and
intermediate­
term
MOEs
for
occupational
risk
were
calculated
based
on
a
NOAEL
of
12
mg/
kg/
day
from
a
rat
developmental
toxicity
study.
The
LOAEL
in
this
study
was
40
mg/
kg/
day;
the
endpoint
is
reduced
bodyweight
gain.

The
short­
term
and
intermediate­
term
MOEs
for
dermal
and
inhalation
exposures
were
calculated
using
an
oral
NOAEL
of
12
mg/
kg/
day
for
both
exposure
durations
(
see
Human
Health
Risk
Assessment
Section
3.3
Dose
Response
Assessment).
The
Agency
also
used
route­
to­
route
extrapolations
to
convert
this
oral
dose
to
dermal
and
inhalation
doses.
A
dermal
absorption
rate
of
9%
was
applied
to
the
dermal
exposure
assessments
and
an
inhalation
absorption
rate
of
100%
was
applied
to
the
inhalation
exposure
assessments.
18
Since
the
effects
from
dermal
and
inhalation
exposure
are
based
on
the
same
oral
study
(
i.
e.
rat
developmental
toxicity
study),
the
exposures
for
these
routes
and
durations
were
combined.

b.
Occupational
Handler
Exposure
Occupational
exposure
to
oxadiazon
via
the
dermal
and
inhalation
routes
may
occur
during
mixing,
loading
and
applying
through
the
use
of
ground
spray,
granular
and
other
turf
application
methods.
Based
on
the
use
patterns,
14
major
occupational
exposure
scenarios
were
identified
for
oxadiazon:

(
1a)
mixing/
loading
wettable
powders
for
chemigation
application;

(
1b)
mixing/
loading
wettable
powders
for
groundboom
application;

(
1c)
mixing/
loading
wettable
powders
for
rights­
of­
way
sprayer;

(
2)
loading
granular
formulations;

(
3)
applying
sprays
with
a
groundboom;

(
4)
applying
sprays
with
a
rights­
of­
way
sprayer;

(
5)
applying
wettable
powder
sprays
with
handgun
sprayer;

(
6)
applying
granules
with
a
tractor
drawn
spreader;

(
7)
mixing/
loading/
applying
sprays
with
a
backpack
sprayer;

(
8)
mixing/
loading/
applying
sprays
with
a
low
pressure
handwand
(
wettable
powder
formulations);

(
9)
mixing/
loading/
applying
sprays
with
a
high
pressure­
handwand
(
wettable
powder
formulations);

(
10)
mixing/
loading/
applying
sprays
with
a
lawn
handgun
(
wettable
powder
formulations);

(
11)
mixing/
loading/
applying
granules
with
a
push
type
spreader;
and,

(
12)
mixing/
loading/
applying
granules
with
a
bellygrinder.

Maximum
single
application
rates
for
oxadiazon
range
from
3
to
4
lb.
ai/
acre,
with
the
higher
rate
being
applied
to
golf
courses,
roadside
turf,
lawns,
parks,
recreational
areas
and
woody
ornamentals.

The
exposure
scenarios
are
of
short­
term
(
1­
30
days)
and
intermediate­
term
(
30
days
to
several
months).
Since
the
use
patterns
for
oxadiazon
do
not
suggest
any
long
term
use,
exposure
scenarios
of
a
longer
duration
were
not
considered.
The
estimated
exposures
considered:

­
baseline
protection
(
long
pants,
long
shirts
and
no
gloves
­
dermal;
no
respirator
­
inhalation),

­
additional
PPE
(
long
pants,
long
shirts
and
chemical
resistant
gloves
and/
or
double
layer
of
clothing
­
dermal;
plus
80%
protection
from
dust/
mist
respirator
­
inhalation),
and
­
engineering
controls
(
use
of
water
soluble
packages
for
wettable
powder
formulations).

EPA
completed
handler
exposure
assessments
first
assuming
the
baseline
level
of
protection
and,
if
required,
increasing
levels
of
risk
mitigation
(
PPE
and
engineering
controls)
to
achieve
an
MOE
of
100
or
19
more
for
non­
cancer
risks.
The
Agency's
assumptions
for
specific
categories
of
handlers
and
equipment
are
as
follows:

$
all
occupational
handlers
are
wearing
footwear
(
socks
plus
shoes
or
boots)

$
occupational
mixers
and
loaders
using
open
mixing
techniques
are
wearing
long­
sleeved
shirts
and
long
pants
and
gloves;
this
represents
minimum
PPE
$
occupational
mixers
and
loaders
using
open
mixing
techniques
are
wearing
long­
sleeved
shirts
and
long
pants,
coveralls
and
gloves;
this
represents
maximum
PPE
$
occupational
applicators
who
use
open
cab
tractor­
driven
application
equipment
are
wearing
longsleeved
shirts
and
long
pants
and
gloves;
this
represents
minimum
PPE.

$
Also,
if
necessary,
dust/
mist
respirator
represented
by
5­
fold
protection
factor
or
an
organic
vapor
respirator
represented
by
a
10­
fold
protection
factor
are
added
to
mitigate
the
risks.

Engineering
control
assumptions
are
as
follows:

$
engineering
controls
are
not
available
for
occupational
handlers
(
mixers,
loaders,
and
applicators)
who
use
hand­
held
application
equipment.

$
occupational
mixers
and
loaders
handling
liquid
formulations
using
a
closed
system
are
wearing
chemical­
resistant
gloves
plus
long­
sleeved
shirts
and
long
pants.

$
occupational
mixers
and
loaders
handling
wettable
powders
using
a
closed
system
(
water­
soluble
packages)
are
wearing
long­
sleeved
shirts
and
long
pants,
and
chemical­
resistant
gloves.

$
occupational
applicators
who
use
tractor­
driven
application
equipment
are
located
in
enclosed
cabs
are
wearing
long­
sleeved
shirts
and
long
pants,
and
no
gloves.

Chemical­
specific
data
for
assessing
human
exposures
during
pesticide
handling
activities
were
not
submitted
to
the
Agency
in
support
of
the
reregistration
of
oxadiazon.
In
such
instances,
it
is
the
policy
of
the
EPA
to
use
data
from
the
Pesticide
Handlers
Exposure
Database
(
PHED)
Version
1.1
to
assess
handler
exposures
for
regulatory
actions
when
chemical­
specific
monitoring
data
are
not
available.
EPA's
level
of
confidence
in
these
data
are
explained
in
detail
in
the
"
Revised
Occupational
and
Residential
Exposure
Assessment
and
Recommendations
for
the
Reregistration
Eligibility
Decision
Document
for
Oxadiazon"
dated
June
7,
2003
(
Tadayon,
2003).

c.
Occupational
Risk
(
noncancer)

The
results
of
the
short­
and
intermediate­
term
handler
assessments
are
presented
in
Table
5
and
indicate
that
potential
non­
cancer
exposure
scenarios
have
MOE(
s)
greater
than
or
equal
to
100
at
either
the
baseline
(
i.
e.,
long
pants,
long
sleeved
shirts,
no
gloves),
PPE
(
i.
e.,
long
pants,
long
sleeved
shirts,
and
chemical
resistant
gloves
while
using
open
systems)
or
using
engineering
controls
(
i.
e.,
water­
soluble
packages).
The
only
exception,
for
which
engineering
controls
are
not
feasible,
is
scenario
8
(
low
pressure
handwand­
wettable
powder
formulations),
with
a
total
MOE
of
46
with
maximum
PPE.
The
low­
pressure
hand
wand
applicator
is
likely
to
be
used
in
non­
turf
areas
of
golf
courses,
such
as
landscaping.
20
Table
5:
Exposure
Variables
(
Noncancer)
and
MOEs
for
Uses
of
Oxadiazon
Exposure
Scenario
(
Scenario
#)
Crop
Type
App
Rates
(
lb
ai/
acre)
Daily
Acres
Treated
Total
MOEs
Base
line
PPE
Eng.
Control
Mixer/
Loader
Mixing/
Loading
Wettable
Powders
for
Chemigation
Application
(
1a)
sod
farms
3
350
2
35
610
Mixing/
Loading
Wettable
Powders
for
Groundboom
Application
(
1b)
conifer
nurseries,
woody
ornamentals
4
40
12
220
NA
herbaceous
ornamentals
3
40
16
300
NA
sod
farms
3
80
8
150
NA
golf
courses
4
40
12
220
NA
Mixing/
Loading
Wettable
Powders
for
Rights­
of­
Way
Sprayer
(
1c)
roadside
turf,
ornamentals
4
40
12
220
NA
Loading
Granular
formulations
(
2)
sod
farms,
conifers
forest
4
80
920
NA
NA
golf
course
turf,
parks,
recreational
areas
4
40
1800
NA
NA
woody
ornamentals
4
40
1800
NA
NA
Applicator
Applying
with
a
Groundboom
(
3)
sod
farms
3
80
1500
NA
NA
herbaceous
ornamentals
3
40
3000
NA
NA
golf
courses
4
40
2300
NA
NA
conifer
nurseries,
woody
ornamentals
4
40
2300
NA
NA
Applying
with
a
Rights­
of­
Way
Sprayer
(
4)
roadsides
4
40
37
120
NA
Applying
Wettable­
Powders
for
Handgun
Applicators
(
ORETF)
(
5)
lawns,
parks,
recreational
areas
4
5
See
PPE
540
NA
Applying
Granular
with
a
Tractor
Drawn
Spreader
(
6)
sod
farms
4
80
1100
NA
NA
golf
courses
4
40
2200
NA
NA
Mixer/
Loader/
Applicator
Backpack
Sprayer
(
LCO)
(
7)
l
awn
s
,
g
o
l
f
c
ou
r
se
s
,
ornamentals
nurseries
4
5
See
PPE
140
NA
Low
Pressure
Handwand
­
Wettable
Powder
Formulations
(
LCO)
(
8)
lawns,
golf
courses,
nursery
stock
4
5
10
46
NF
High
Pressure
Handwand
­­
(
Wettable
Powder
Formulations)
(
9)
woody
ornamentals,
conifer
nurseries.
4
5
See
PPE
100
NA
Table
5:
Exposure
Variables
(
Noncancer)
and
MOEs
for
Uses
of
Oxadiazon
Exposure
Scenario
(
Scenario
#)
Crop
Type
App
Rates
(
lb
ai/
acre)
Daily
Acres
Treated
Total
MOEs
Base
line
PPE
Eng.
Control
21
Lawn
Handgun
(
Wettable
Powder
Formulations)
(
ORETF)
(
10)
ornamentals,
lawns,
parks
rec
areas
4
5
280
NA
NA
Granulars
with
a
Push
Type
Spreader
(
ORETF)
(
11)
lawns,
golf
courses,
parks,
r
ecreat
iona
l
ar
ea
s
,
ornamentals
4
5
1100
NA
NA
Granulars
with
a
Bellygrinder
(
LCO)
(
12)
golf
courses,
parks,
rec
areas.
4
1
190
NA
NA
Baseline
dermal
unit
exposure
scenarios
includes
long
pants,
long
shirts
and
no
gloves.

Baseline
inhalation
unit
exposure
represents
no
respirator
PPE
dermal
unit
exposure
includes
long
pants,
long
shirts
and
gloves
for
scenarios
5,
7,
and
9.

PPE
dermal
unit
exposure
includes
long
pants,
long
shirts
gloves
and
double
layer
(
50%
protection)
for
scenarios
1a,
1b,
1c,
and
8.

PPE
inhalation
unit
exposure
represents
dust/
mist
respirator
(
80
%
protection)
for
scenarios
1a,
1b,
1c,
and
8.

Engineering
Control
dermal
unit
exposure
scenarios
includes
long
pants,
long
shirts,
gloves
and
water
soluble
packages
for
scenario
1a.

Engineering
inhalation
unit
exposure
represents
no
respirator.

NA
=
Not
applicable.

NF
=
Not
Feasible.
No
engineering
controls
are
available
to
mitigate
risk.
22
d.
Occupational
Handler
Risk
(
cancer)

The
cancer
risk
assessments
for
handlers
used
baseline
PPE
and,
as
needed,
increasing
levels
of
risk
mitigation
(
PPE
and
engineering
controls)
to
achieve
cancer
risks
below
EPA's
level
of
concern.
As
noted
previously,
the
Agency's
level
of
concern
for
cancer
risks
for
occupational
exposure
to
pesticides
ranges
from
1.0
x
10­
4
to
1.0
x
10­
6,
depending
on
the
feasibility,
availability,
and
cost
of
various
mitigation
options.

Potential
cancer
risks
to
handlers
were
assessed
using
the
following
assumptions:

$
an
average
typical
adult
body
weight
of
70kg;

$
typical
working
lifetime
of
35
years;

$
70
year
lifetime;

$
dermal
absorption
of
9%
and
inhalation
absorption
of
100%
of
the
oral
dose.

Based
on
the
scenarios
identified
above,
the
Agency
estimates
that
cancer
risks
from
occupational
dermal
and
inhalation
exposures
to
oxadiazon
range
from
1.7
x
10­
2
to
4.7
x
10­
7
during
"
baseline"
conditions
(
i.
e.
long
pants,
long­
sleeves,
no
gloves).
Cancer
risk
ranges
from
1.0
x
10­
3
to
1.4
x
10­
7
when
PPE
was
used.
The
Agency
estimates
that
cancer
risk
decreases
to
a
range
of
5
x
10­
5
to
1
x
10­
8
with
engineering
controls.
Engineering
controls
included
the
use
of
chemical­
resistant
gloves
along
with
water
soluble
packaging
for
wettable
powder
formulations.
Overall
these
estimates
suggest
that
when
PPE
and/
or
engineering
controls
are
used,
none
of
the
evaluated
scenarios
have
cancer
risks
that
exceed
1.0
x10­
4
,
but
most
are
in
the
range
where
further
consideration
is
warranted.

e.
Occupational
Exposure
and
Risk,
Post­
application
(
non­
cancer)

EPA
uses
the
term
"
post­
application"
to
describe
those
individuals
who
can
be
exposed
to
pesticides
after
entering
areas
previously
treated
with
pesticides
and
performing
certain
tasks
or
activities
(
also
often
referred
to
as
reentry
exposure).
Most
of
the
oxadiazon
used
is
applied
either
pre­
plant
or
when
the
crops
are
quite
small
(
early
post­
emergence).
This
fact,
and
the
degree
of
mechanization,
minimizes
the
postapplication
contact
of
workers
with
oxadiazon.
However,
the
Agency
has
determined
that
there
are
potential
post­
application
exposures
to
individuals
re­
entering
oxadiazon
treated
areas
for
the
purpose
of:

°
Roadsides:
mowing
°
Bermuda
grass
rights­
of­
way:
mowing
°
Sod
farms:
mowing
and
harvesting
°
Golf­
course
turf:
mowing
Based
on
usage
information
provided
by
the
registrants
for
reregistration,
the
most
common
postapplication
exposures
for
oxadiazon
will
occur
for
workers
on
turf.
Based
on
label
restrictions
and
pattern
of
use,
oxadiazon
is
applied
early
in
the
season,
either
pre­
plant
or
before
weeds
emerge
(
pre­
emergence).
Mowing
would
be
a
common
post­
application
activity
after
either
spraying
method.
Treated
turf
or
grasses
23
will
routinely
require
reentry
activities,
such
as
mowing
and
watering,
and
eventually
harvesting
in
the
case
of
sod
farms.

Because
oxadiazon
has
a
low
vapor
pressure
(
1.0
x
10­
6mm
Hg)
and
is
only
used
outdoors,
the
inhalation
component
of
post­
application
exposure
is
anticipated
to
be
negligible.
Therefore,
all
calculations
of
post­
application
risk
estimates
have
been
done
for
dermal
exposure
only.

For
short­
and
intermediate­
term
non­
cancer
risks,
mowing
(
e.
g.,
golf
courses,
roadsides,
and
sod
farms)
and
harvesting
(
e.
g.,
sod
farms)
scenarios
were
considered.
Transfer
coefficients
of
500
and
16,500
cm2/
hr
were
used,
based
on
the
Agricultural
Re­
entry
Task
Force
data
(
refer
to
EPA
Exposure
SAC
Policy
guidance
3.1,
8/
00).
Occupational
post­
application
activities
had
MOEs
of
30­
1000
at
day
0.
This
information
is
summarized
below
in
Table
6.

f.
Occupational
Risk,
Post­
application
(
cancer)

Cancer
risks
for
occupational
post­
application
scenarios
were
estimated
not
to
exceed
EPA's
level
of
concern
(
i.
e.

1.0
x
10­
4;
Table
6).

Table
6:
Occupational
Short­
and
Intermediate­
Term
Postapplication
Risks
for
Oxadiazon
at
Day
0
Crop/
Use
Pattern
Application
Rate
(
lb
ai/
acre)
Postapplication
Activity
Transfer
Coefficienta
Cancer
Risk
MOEb
LADDc
mg/
kg/
day
Riskd
Golf
Course
Turf
4
Mow,
seed,
scout,
mechanical
weed,
aerate,
fertilize,
prune
500
1000
4.23e­
5
3.01e­
6
Transplant,
hand
weed
16,500
30
1.39e­
3
9.92e­
5
Sod
Farms
4
Mow,
scout,
mechanical
weed,
irrigate
500
1000
4.23e­
5
3.01e­
6
Transplant,
hand
weed,
harvest
(
hand
or
mechanical)
16,500
30
1.39e­
3
9.92e­
5
Bermuda
Grass
Rights
of
Way
4
Mow,
seed,
scout,
mechanical
weed,
aerate,
fertilize
500
1000
4.23e­
5
3.01e­
6
aTransfer
coefficient
from
Science
Advisory
Council
for
Exposure:
Policy
Memo
#
003
.1
"
Agricultural
Transfer
Coefficients,"
Revised
­
August
7,
2000.

bMOE
=
Short­
term
NOAEL
(
12
mg/
kg/
day;
based
on
a
dermal
study)
/
dermal
dose
where
absorbed
dose
=
TTR
(

g/
cm2)
x
TC
(
cm2/
hr)
x
conversion
factor
(
1
mg/
1,000

g)
x
exposure
time(
8hrs/
day)
x
dermal
absorption
(
9
%)
/
body
weight
(
60
kg;
adult).

CAbsorbed
dermal
dose
where
absorbed
dose
=
TTR
(

g/
cm2)
x
TC
(
cm2/
hr)
x
conversion
factor
(
1
mg/
1,000

g)
x
exposure
time
(
8
hrs/
day)
x
dermal
absorption
(
9
%)
/
body
weight
(
70
kg)
x
(
Number
of
days
(
3)
exposure
per
year
applicator)
/
365
days
per
year)
x
35
years
worked/
70
year
lifetime
dCancer
Risk
=
LADD
(
mg/
kg/
day)
x
(
Q1*),
where
Q1*
=
7.11e­
2
(
mg/
kg/
day)­
1.

7.
Incident
Data
24
Oxadiazon
has
not
been
reported
to
cause
life­
threatening
illness
or
death
in
humans.
On
the
list
of
the
top
200
chemicals
for
which
National
Pesticide
Information
Center
(
NPIC,
formerly
National
Pesticide
Telecommunications
Network)
received
calls
from
1984­
1991
inclusively,
oxadiazon
was
ranked
192nd
with
12
incidents
in
humans
reported
and
five
incidents
in
animals
(
mostly
pets).
Most
of
the
cases
appear
to
be
related
to
irritation
to
the
skin,
eyes
and
mucous
membranes.

B.
Environmental
Risk
Assessment
A
summary
of
the
Agency's
environmental
fate
and
effects
risk
assessment
is
presented
below.
More
detailed
information
on
the
environmental
and
ecological
risks
associated
with
the
use
of
oxadiazon
may
be
found
in
the
"
EFED
Revised
Risk
Assessment
for
the
Reregistration
Eligibility
Decision
of
Oxadiazon,"
dated
June
11,
2003.
Since
that
document
was
completed,
the
Agency
made
changes
to
refine
its
assessment
of
the
chronic
surface
water
concentrations
of
oxadiazon
associated
with
the
use
on
turf.
Specifically,
the
Tier
1
model
simulations
were
refined
using
the
Tier
2
PRZM/
EXAMS
model
simulation
with
a
turf
scenario.
The
linked
PRZM/
EXAMS
models
are
typically
used
by
EPA
in
estimating
pesticide
concentrations
in
surface
waters.
The
PRZM
model
estimates
the
amount
of
pesticide
that
reaches
a
body
of
surface
water
as
a
result
of
runoff.
The
EXAMS
model
estimates
pesticide
concentrations
by
taking
into
account
different
mechanisms
for
dissipation,
weather
patterns,
and
periodic
application
of
pesticide,
for
several
years.
The
complete
environmental
fate
and
effects
risk
assessment
and
related
addenda
are
not
included
in
this
document,
but
are
available
on
the
Agency's
web
page
at
www.
epa.
gov/
pesticides,
and
in
the
Public
Docket.

1.
Environmental
Fate
and
Transport
Based
on
the
fate
studies
reviewed,
oxadiazon
would
be
stable
and
persistent
under
typical
terrestrial
environment
conditions.
Soil
photolysis
and
hydrolysis
under
acidic
and
basic
conditions
do
not
appear
to
be
an
important
dissipation
mechanism.
However,
direct
aqueous
photolysis
halflife
of
about
three
days
(
summer
sunlight
conditions
in
Florida)
suggests
that
in
clear
and
shallow
surface
water
bodies
where
sunlight
penetration
can
be
significant,
photolytic
degradation
of
oxadiazon
is
possible.
The
photolytic
effect
may
substantially
diminish
in
turbid
and
deeper
water
bodies.

Microbial
metabolism
in
soil
and
aquatic
environments
under
either
aerobic
and
anaerobic
conditions
is
not
expected
to
cause
any
significant
transformation
of
oxadiazon,
although
a
number
of
degradates
have
been
reported
from
the
different
chemical
and
biological
fate
studies.

Studies
on
equilibrium
sorption
and
aged/
unaged
oxadiazon
indicate
that
the
pesticide
has
low
environmental
mobility
(
K
d's
ranged
from
8.17
to
22.83;
K
oc's
ranged
from
1409
to
3268).
Thus,
oxadiazon
is
likely
to
be
transported,
via
surface
runoff,
bound
to
erodible
soil
particles,
to
nearby
surface
water
bodies.
Leaching
from
surficial
soils
to
groundwater
is
expected
to
be
low
or
25
negligible,
unless
the
soil
is
very
porous
or
has
some
cracks
that
favor
preferential
flow.
Oxadiazon
exhibited
slow
dissipation
in
two
terrestrial
field
studies
conducted
in
California
and
North
Carolina.

2.
Water
Resources
The
potential
impact
to
water
quality
from
the
use
of
oxadiazon
on
turf
is
essentially
due
to
the
parent
(
as
opposed
to
possible
degradates).
Oxadiazon
appears
to
be
persistent
under
most
environmental
conditions
making
the
chemical
available
for
surface
runoff.
The
remaining
factor
which
affects
the
impact
of
oxadiazon
on
water
quality
is
mobility
in
soils.
A
soil
column
leaching
study,
and
supplemental
batch
equilibrium
studies,
indicate
that
oxadiazon
has
low
mobility
in
the
various
soils
tested.
Ordinarily
this
would
mean
that
the
chemical
would
remain
soil
bound
and
would
be
transported
to
a
water
body
on
eroded
soil.
Turf
scenarios,
however,
offer
different
challenges
than
typical
agricultural
crops.
The
turf
itself
offers
a
vegetative
interception
layer
(
including
thatch)
that
prevents
rapid
deposition
of
the
oxadiazon
on
the
surface
of
the
soil.
Both
liquid
and
granular
formulation
labels
of
oxadiazon
recommend
mowing
the
grass
prior
to
application.
Also,
both
liquid
and
granular
formulation
labels
of
oxadiazon
specify
that
the
chemical's
effectiveness
is
improved
if
it
is
wetted
in
after
application.
Oxadiazon
is
more
likely
to
bind
to
soil
particles
if
the
turf
is
watered
after
application
of
the
pesticide.

The
models
used
for
the
Tier
1
determination
of
the
water
exposures
were
FIRST,
GENEEC
2.0
for
surface
waters,
and
SCIGROW
for
ground
waters.
The
models
are
screening
tools
designed
to
provide
upper­
bound
estimates
of
the
concentrations
that
might
be
found
due
to
the
use
of
oxadiazon.
For
drinking
water,
a
Tier
II
refinement
was
performed,
using
PRZM/
EXAMS.
In
the
Tier
II
refinement,
a
scenario
that
incorporates
three
applications
(
1
@
4
lb
a.
i./
A
and
2
@
2
lb
ai/
A)
was
used.
Surface
water
monitoring
data
for
oxadiazon
is
limited
and
has
not
been
used
to
represent
possible
concentrations
of
oxadiazon
in
surface
waters.
The
chemical
is
not
included
in
the
NAWQA
monitoring
studies.
The
STORET
database
contained
only
two
samples
taken
from
the
same
location
within
an
interval
of
only
four
days.
The
estimated
recommended
acute
and
long
term
drinking
water
concentrations
are
detailed
in
Chapter
6
of
the
document
"
EFED
Revised
Risk
Assessment
for
the
Reregistration
Eligibility
Decision
of
Oxadiazon,"
dated
June
11,
2003.

3.
Ecological
Risk
Risk
characterization
integrates
the
results
of
the
exposure
and
ecotoxicity
data
to
evaluate
the
likelihood
of
adverse
ecological
effects.
The
Agency
calculates
risk
quotients
(
RQs)
by
dividing
exposure
estimates
by
acute
and
chronic
ecotoxicity
values:

RQ
=
EXPOSURE/
TOXICITY
RQs
are
then
compared
to
OPP's
levels
of
concern
(
LOCs).
These
LOCs
are
criteria
used
by
EPA
to
indicate
potential
risk
to
nontarget
organisms.
The
criteria
indicate
that
a
pesticide
used
as
directed
has
the
potential
to
cause
adverse
effects
on
nontarget
organisms.
The
exposure
and
effects
inputs
to
a
screening­
level
assessment
are
by
design
assumed
to
overestimate
likely
exposures
and
26
effects
of
pesticides.
Exceedence
of
an
LOC
indicates
that
risks
of
concern
are
possible,
but
the
likelihood,
magnitude,
and/
or
severity
of
the
risk
cannot
be
quantified.
Risk
presumptions,
along
with
the
corresponding
LOCs,
are
given
in
Table
7
below.

Table
7.
Risk
Presumptions
for
Terrestrial
and
Aquatic
Animals
Risk
Presumption
LOC
terrestrial
animals
LOC
aquatic
animals
Acute
Risk­
there
is
potential
for
acute
risk;
mitigation
may
be
warranted
in
addition
to
restricted
use
classification,
0.5
0.5
Acute
Restricted
Use
­
there
is
potential
for
acute
risk,
but
may
be
mitigated
through
restricted
use
classification,
0.2
0.1
Acute
Endangered
Species
­
endangered
species
may
be
adversely
affected,
0.1
0.05
Chronic
Risk
­
there
is
potential
for
chronic
risk;
regulatory
action
may
be
warranted.
1
1
Aquatic
and
terrestrial
risk
assessments
were
conducted
by
using
standard
ecotoxicity
endpoints
(
i.
e.,
LD
50
and
LC
50
values,
and
NOAEC
values).
The
toxicity
endpoints
chosen
for
use
in
the
ecological
risk
assessment
are
summarized
below
in
Table
8.

Table
8.
Toxicological
Endpoints
Used
to
Determine
Risk
Quotients
(
RQs)

Type
Of
Toxicity
Organism
Species
Toxicological
Endpoint
Oral
Acute
Bird
Mallard
1040
mg/
kg
Dietary
Bobwhite/
Mallard
>
5000
ppm
Chronic
Bobwhite
500
ppm
1
Oral
Acute
Mammal
Rat
>
5000
mg/
kg
Chronic
Rat
200
ppm
2
Acute
Freshwater
Fish
Rainbow
trout/
Bluegill
0.88
ppm
Chronic
Rainbow
trout
0.88
ppb
3
Acute
Freshwater
Invertebrates
Daphnid
2.18
ppm
Chronic
Daphnid
0.03
ppm
Acute
Estuarine
Fish
Sheepshead
Minnow
1.5
ppm
Chronic
Sheepshead
Minnow
0.0015
ppm
4
Table
8.
Toxicological
Endpoints
Used
to
Determine
Risk
Quotients
(
RQs)

Type
Of
Toxicity
Organism
Species
Toxicological
Endpoint
27
Acute
Estuarine
Invertebrates
Mysid
0.27
ppm
Chronic
Mysid
0.0037ppm4
Acute
Aquatic
Plants
(
vascular)
duckweed
EC50
=
41
ppb
NOAEC
=
<
8
ppb
(
Nonvascular)
marine
diatom
EC50
=
5.2
ppb
1
No
effects
on
any
reproductive
parameter
or
viability
of
F1
offspring
at
the
highest
dose
tested,
1000
ppm;
however
due
to
excessive
mortality
(
33%)
of
adult
female
birds
in
that
dose
level,
a
NOAEC
for
chronic
effects
was
set
at
500
ppm.

2
LOAEL
of
>
38
mg/
kg/
day
for
inactive
mammary
tissue
and
fetal/
pup
death
observed
in
the
one
year
range­
finding
test
of
a
rat
reproduction
study.
NOAEC
>
200
ppm.

3
Rainbow
trout
was
more
sensitive
than
the
fathead
minnow
(
fathead
minnow
NOAEC=
33
ppb).

4
Extrapolation
from
acute/
chronic
ratio.

j.
Risks
to
Birds
Table
9
provides
avian
acute
and
chronic
RQs
from
exposure
to
multiple
applications
of
oxadiazon
EC
to
turf
for
the
maximum
three
application
rates
(
4.0,
3.0
and
2.0
lbs
ai/
A)
and
two
split
applications
(
1.0
lb
ai/
A,
4
times/
6
months;
1.3
lbs
ai/
A,
3
times/
6
months).
The
maximum
three
applications
have
the
potential
for
chronic
exposure
to
birds
that
feed
on
plants
and
grass
(
e.
g.,
ducks,
geese)
and
may
result
in
risk
to
these
birds
(
RQ
=
1.0
­
2.0).
The
split
application
appears
to
lower
this
chronic
exposure
and
risk
(
RQ
=
<
1).
The
EC
formulation
was
evaluated
because
it
presents
an
upper­
bound
estimate
of
risk.
The
majority
of
oxadiazon
is
applied
as
a
granular
formulation.
Exposure
from
the
granular
formulation
was
evaluated
because
birds
may
be
exposed
to
granular
pesticides
through
ingestion
when
foraging
for
food
or
grit.
RQ
values
were
calculated
for
three
weight
classes
of
birds
(
1000g
waterfowl,
180g
upland
game
bird,
and
20g
songbird).
All
scenarios
for
the
granular
resulted
in
no
acute
risk
to
birds
(
RQ
<
0.5).
However,
the
potential
chronic
concern
noted
for
non­
endangered
birds
suggest
that
oxadiazon
may
present
a
risk
to
endangered
species
(
RQ
>
0.1).

Pesticide
dissipation
from
foliar
surfaces
is
primarily
due
to
degradation
or
dissipation
by
one
or
more
processes
including
photolysis,
hydrolysis,
microbial
degradation
and
volatilization.
Since
adequate
foliar
dissipation
data
are
not
available
for
oxadiazon,
a
default
half­
life
of
35
days
was
used
in
the
EEC
calculations.
28
Table
9.
Avian
Acute
and
Chronic
Risk
Quotients
a
Site
Application
Rate
lbs
ai/
A
(#
appl)
Food
Item
Maximum
EECs
(
ppm)
Acute
RQ
(
EEC/
LC50)
Chronic
RQ
(
Max.

EEC/
NOAEC)

Turf
(
EC)

4.0
(
2)
Short
grass
Tall
grass
Broadleaf
plants/
insects
Seeds
984.1
451.1
553.6
61.5
<
0.2
<
0.1
<
0.1
<
0.0
2.0
1.0
0.1
0.1
Turf
(
EC)

3.0
(
2)
Short
grass
Tall
grass
Broadleaf
plants/
insects
Seeds
739.6
339.0
416.0
46.2
<
0.1
0.0
<
0.1
0.0
1.5
1.0
1.0
0.1
Turf
(
EC)

2.0
(
2)
Short
grass
Tall
grass
Broadleaf
plants/
insects
Seeds
493.1
226.0
277.3
30.8
<
0.1
0.0
0.0
0.0
1.0
0.4
0.5
0.1
Turf
(
EC)

1.0
(
split
4
applications/
6
months)
Short
grass
Tall
grass
Broadleaf
plants/
insects
Seeds
424.4
194.5
238.7
26.5
<
0.1
0.0
0.0
0.0
1.0
0.4
0.5
0.1
Turf
(
EC)

1.3
(
split
3
applications/
6
months)
Short
grass
Tall
grass
Broadleaf
plants/
insects
Seeds
257.0
117.8
144.6
16.1
<
0.1
0.0
0.0
0.0
1.0
0.4
0.5
0.1
aAvian
acute
and
chronic
risk
quotients
(
RQ's)
as
generated
through
ELL­
FATE
for
broadcast
ground
spray
applications
for
oxadiazon.
RQ's
are
based
on
mallard
duck
LC50
>
5,000
ppm
and
NOAEC
=
500
ppm.
The
EEC
reflects
the
turf
use
with
the
three
highest
use
rate
(
4.0,
3.0
and
2.0
lbs
ai/
A,
2
applications)
and
two
split
applications
(
1.0
lb
ai/
A,
4
times/
6
months;
1.3
lbs
ai/
A,
3
times/
6
months).
29
b.
Risks
to
Mammals
The
Agency
has
concluded
that
for
the
EC
formulation
of
oxadiazon
the
assessed
single
applicaton
rates
(
4.0,
3.0
and
2.0
lbs
ai/
A),
as
well
as
the
split
use
rates
(
1.0
and
1.3
lbs
ai/
A)
should
not
result
in
acute
risk
to
mammals
(
RQ
<
0.2).
However,
these
application
scenarios
can
result
in
chronic
exposure
and
risk
to
mammalian
herbivores
and
insectivores
(
15g,
35g,
and
1000g)
with
RQ
values
ranging
from
0.1
to
4.9
(
Table
10).
This
chronic
risk
to
non­
endangered
mammalian
species
also
suggests
the
potential
for
impact
to
endangered
species.

Table
10.
Mammalian
Chronic
Risk
Quotientsa
Crop
Application
Rate
lbs
ai/
A
(
#
of
applications)
Food
Items
Max.

EEC
(
ppm)
Chronic
RQ
(
Max.
EEC/
NOAEC)
b
Turf
(
EC)

4.0
(
2)
Short
Grass
Tall
Grass
Broadleaf
plant/
Insects
Seeds
986.1
452.0
554.7
61.6
4.9
2.3
2.8
0.3
Turf
(
EC)

3.0
(
2)
Short
Grass
Tall
Grass
Broadleaf
plant/
Insects
Seeds
739.6
339.0
416.0
46.2
3.7
1.7
2.1
0.2
Turf
(
EC)

2.0
(
2)
Short
Grass
Tall
Grass
Broadleaf
plant/
Insects
Seeds
493.1
226.0
227.3
30.8
2.4
1.1
1.4
0.1
Turf
(
EC)

1.0
(
split
4
applications/

6
months)
Short
Grass
Tall
Grass
Broadleaf
plant/
Insects
Seeds
424.4
194.5
238.7
26.5
2.4
1.1
1.3
0.1
Turf
(
EC)

1.3
(
split
3
applications/

6
months)
Short
Grass
Tall
Grass
Broadleaf
plant/
Insects
Seeds
257.0
117.8
144.6
16.1
1.6
1.0
1.0
0.1
aMammalian
chronic
risk
quotients
as
generated
through
ELL­
FATE
for
ground
application
of
an
emulsifiable
concentrate
of
oxadiazon
are
based
on
rat
(
Rattus
norvegicus)
NOAEC
=
200
ppm.
The
EEC
reflects
the
three
highest
assessed
application
rates
(
4.0,
3.0
and
2.0
lbs
ai/
A,
2
applications)
and
two
split
applications
(
1.0
lb
ai/
A,
4
times/
6
months;
1.3
lbs
ai/
A,
3
times/
6
months).

b
Chronic
risk
(
LOC
>
1)
30
c.
Risks
to
Fish
and
Aquatic
Invertebrates
Tables
11
and
12
provide
acute
and
chronic
RQ
values
for
oxadiazon
exposure
to
freshwater
and
estuarine/
marine
species
for
turf
use
patterns
(
application
rates
for
EC
at
2.0
­
4.0
lbs
ai/
A
and
4.0
lbs
ai/
A
for
granular).
Although
our
assessment
suggests
that
oxadiazon
acute
exposure
may
result
in
low
acute
risk
to
fish
(
RQ
=
0.1
­
0.2)
and
invertebrates
(
RQ
=
0.3
­
0.5),
there
is
uncertainty
regarding
the
potential
for
enhanced
risk
that
may
occur
through
phototoxicity.
Since
oxadiazon
is
a
light­
dependent
peroxidizing
herbicide
(
LDPH),
enhanced
toxicity
through
exposure
to
high
levels
of
solar
radiation
is
a
possible
concern
regarding
aquatic
organisms
that
inhabit
small,
shallow
water
bodies.

EPA's
Tier
I
(
GENEEC)
risk
assessment
suggests
that
chronic
exposure
to
this
compound
can
result
in
risk
to
freshwater
and
estuarine/
marine
fish
(
RQ
=
39.3
­
131.8)
and
aquatic
invertebrates
(
RQ
=
3.9
­
36.7).
Endangered
species
concerns
are
also
suggested,
as
acute
RQs
exceeded
the
level
of
concern
(
0.1).
Also,
enhanced
toxicity
through
exposure
to
high
levels
of
solar
radiation
may
increase
toxic
risk
to
aquatic
organisms
that
inhabit
small,
shallow
water
bodies.
Therefore,
EPA
is
requiring
a
study
on
the
phototoxicity
of
oxadiazon
in
fathead
minnows.

The
Tier
I
GENEEC
model
60­
day
EEC
for
oxadiazon
in
surface
water
following
2­
4
lb
applications
of
granular
oxadiazon
was
142
ppb.
However,
the
conservative
Tier
I
model
does
not
account
for
the
effect
of
established
golf
course
turf
on
reducing
sediment
run­
off.
Tier
II
PRZM/
EXAMS
estimates
of
EECs
for
drinking
water,
although
not
directly
applicable
to
the
risk
assessment
for
aquatic
organisms,
suggest
that
the
golf
course
scenario
greatly
reduces
run­
off.
Tier
II
estimates
of
oxadiazon
concentrations
in
surface­
sourced
drinking
water
were
approximately
sixfold
lower
than
the
Tier
I
GENEEC
estimate
described
above.
It
is
reasonable
to
assume
that
Tier
II
EECs
for
a
pond
scenario
would
likewise
be
reduced.

Table
11.
Acute
and
Chronic
RQ's
for
Oxadiazon
Exposure
to
Fish
a
Crop
App.
Rate
(
lbs
ai/
A;
#
App.)
Organism
Acute
(
LC50,
ppm)
Chronic
(
NOAEC,
ppm)
EEC
Peak
(
ppm)
EEC
60­
Day
Avg.

(
ppm)
Acute
RQ
(
EEC/
LC50)
Chronic
RQ
d
(
EEC/
NOAEC)

Turf
(
EC)

4.0
(
2)
Freshwater
0.88
0.00088
0.143
0.116
0.2
c
131.8
Estuarine/

Marine
1.5
0.0015
b
0.143
0.116
0.1
c
77.3
Turf
(
EC)

3
(
2)
Freshwater
0.88
0.00088
0.130
0.122
0.1
c
139.0
Estuarine/

Marine
1.5
0.0015
b
0.130
0.122
0.1
c
81.3
Turf
(
EC)

2
(
2)
Freshwater
0.88
0.00088
0.088
0.083
0.1
c
94.3
Table
11.
Acute
and
Chronic
RQ's
for
Oxadiazon
Exposure
to
Fish
a
31
Estuarine/

Marine
1.5
0.0015
b
0.088
0.083
0.0
55.3
Turf
(
Granular)

4.0
(
2)
Freshwater
0.88
0.00088
0.122
0.099
0.1
c
112.5
Estuarine/

Marine
1.5
0.0015
b
0.122
0.099
0.1
c
66.0
aAcute
and
chronic
RQ's
for
evaluating
toxic
risk
of
oxadiazon
exposure
to
fish
(
freshwater
and
estuarine/
marine).
RQ's
are
based
on
the
bluegill
(
Lepomis
macrochirus)
LC50
=
0.88
ppm,
rainbow
trout
(
Oncorhynchus
mykiss)
NOAEC
=
0.00088
ppm
and
sheepshead
minnow
(
Cyprinodon
variegatus)
LC50
=
1.5
ppm.,
NOAEC
=
0.0015
ppm1.
EEC
values
are
generated
from
GENEEC
and
reflect
three
of
the
highest
assessed
EC
application
rates,
and
the
maximum
assessed
granular
use
rate
(
4.0,
3.0,
and
2.0
lbs
ai/
A,
2
applications
each;
4.0
lbs
ai/
A,
2
applications,
respectively)
for
turf
use.

b
Extrapolated
chronic
value
using
acute/
chronic
freshwater
toxicity
ratio
c
Acute
restricted
use
(>
0.1),
acute
species
d
Chronic
concern
(>
1.0)
32
Table
12.
Acute
and
Chronic
Risk
Quotients
for
Aquatic
Invertebratesa
Crop
App.
Rate
(
lbs
ai/
A)
#
App.
(
days)
Organism
Acute
(
EC50,
ppm)
Chronic
(
NOAEC,
ppm)
EEC
Peak
(
ppm)
EEC
21­
Day
Ave.

(
ppm)
Acute
RQ
(
EEC/

LC50)
Chronic
RQ
(
EEC/
NOAEC)

Turf
(
EC)

4.0
(
2)
Freshwater
2.18
0.03
0.143
0.136
0.12
4.51
Estuarine/

Marine
0.27
0.0037
0.143
0.136
0.52
36.71
Turf
(
EC)

3.0
(
2)
Freshwater
2.18
0.03
0.130
0.127
0.52
4.21
Estuarine/

Marine
0.27
0.0037
0.130
0.127
0.52
34.33
Turf
(
EC)

2.0
(
2)
Freshwater
2.18
0.03
0.088
0.086
0.0
2.93
Estuarine/

Marine
0.27
0.0037
0.088
0.086
0.32
23.23
Turf
(
Granular)

4.0
(
2)
Freshwater
2.18
0.03
0.122
0.116
0.0
3.91
Estuarine/

Marine
0.27
0.0037
0.122
0.116
0.42
31.31
aAcute
and
chronic
risk
RQ's
for
evaluating
toxic
risk
of
oxadiazon
exposure
to
aquatic
invertebrates
(
freshwater
and
estuarine
/
marine).
RQ's
are
based
on
Daphnia
(
Daphnia
magna)
EC50
=
2.18
ppm,
NOAEC
=
0.03
ppm
and
the
Mysid
shrimp
(
Americamysis
bahia)
EC50
=
0.27
ppm,
NOAEC
=
0.0037
ppm1.
EEC
values
are
generated
from
GENEEC
and
reflect
three
of
the
highest
proposed
EC
application
rates,
and
the
maximum
granular
use
rate
(
4.0,
3.0,
and
2.0
lbs
ai/
A,
2
applications
each;
4.0
lbs
ai/
A,
2
applications,
respectively)
for
turf
use.

1
Extrapolated
chronic
value
using
acute/
chronic
freshwater
toxicity
ratio
2
Acute
restricted
use
(>
0.1)

3
Chronic
concern
(>
1.0)
33
d.
Risk
to
Benthic
Organisms
Oxadiazon
residues
can
accumulate
in
sediments
and
may
increase
the
risk
from
chronic
exposure
of
benthic
and
epibenthic
organisms­­
aquatic
organisms
that
live
in
or
on
the
sediment.
In
order
to
better
understand
this
potential
risk,
EPA
is
requiring
appropriate
acute
and
chronic
sediment
toxicity
testing
on
this
compound.

e.
Risks
to
Aquatic
Plants
Exposure
to
non­
target
aquatic
plants
may
occur
through
runoff
or
spray
drift
from
adjacent
treated
sites.
An
aquatic
plant
acute
risk
assessment
is
usually
made
for
aquatic
vascular
plants
from
the
surrogate
duckweed
Lemna
gibba.
Non­
vascular
acute
aquatic
plant
risk
assessments
are
performed
using
either
algae
or
a
diatom,
whichever
is
the
most
sensitive
species.
Runoff
and
drift
exposure
are
computed
from
GENEEC2
and
the
risk
quotient
is
determined
by
dividing
the
pesticide's
initial
or
peak
concentration
in
water
by
the
plant
EC
50
value.
Acute
risk
quotients
for
vascular
and
non­
vascular
plants
are
tabulated
in
Table
13.

Aquatic
plant
acute
risk
levels
of
concern
are
exceeded
(
Table
13)
for
both
vascular
and
nonvascular
plants.
The
RQs
range
from
1.1
to
4.2
for
vascular
plants
and
from
8.5
­
33
for
nonvascular
plants.
The
acute
plant
risk
level
of
concern
is
exceeded
for
vascular
plants
with
RQs
ranging
of
5.5
­
22.
Currently,
EPA
does
not
perform
assessments
for
chronic
risk
to
aquatic
plants.

The
Tier
I
GENEEC
model
60­
day
EEC
of
oxadiazon
in
surface
water
following
2­
4
lb
applications
of
granular
oxadiazon
was
142
ppb.
However,
the
conservative
Tier
I
model
does
not
account
for
the
effect
of
established
golf
course
turf
on
reducing
sediment
run­
off.
Tier
II
PRZM/
EXAMS
estimates
of
EECs
for
drinking
water,
although
not
directly
applicable
to
the
risk
assessment
for
aquatic
organisms,
suggest
that
the
golf
course
scenario
greatly
reduces
run­
off.
Tier
II
estimates
of
oxadiazon
concentrations
in
surface­
sourced
drinking
water
were
approximately
sixfold
lower
than
the
Tier
I
GENEEC
estimate
described
above.
It
is
reasonable
to
believe
that
Tier
II
EECs
for
a
pond
scenario
would
likewise
be
reduced.
34
Table
13.
Acute
Risk
Quotients
for
Aquatic
Plants
a
Turf/
Rate
of
Application
in
lbs
ai/
A
(
Number
of
Applications).
Species
EC50
(
ppm)
EEC
(
ppm)
Non­
target
plant
RQ
(
EEC/
EC50)

4
(
2)
duckweed
0.041
0.173
4.2
4
(
1)
"
0.041
0.089
2.2
3
(
1)
"
0.041
0.067
1.6
2
(
1)
"
0.041
0.044
1.1
4
(
2)
diatom
0.0052
0.173
33.3
4
(
1)
"
0.0052
0.089
17.1
3
(
1)
"
0.0052
0.067
12.9
2
(
1)
"
0.0052
0.044
8.5
aAcute
risk
quotients
for
aquatic
plants
are
based
upon
a
duckweed
(
Lemna
gibba)
EC50
of
41
ppb
and
a
nonvascular
plant
(
marine
diatom)
EC50
of
5.2
ppb.

4.
Endangered
Species
Risk
Assessment
Endangered
species
LOCs
for
liquid
and
granular
formulations
of
oxadiazon
are
exceeded
for
acute
risks
to
birds,
mammals,
freshwater
and
estuarine
fish
and
invertebrates
and
aquatic
vascular
plants.
Although
the
terrestrial
plant
data
are
outstanding,
it
is
assumed
that
endangered
terrestrial
plants
are
at
risk
since
oxadiazon
is
an
herbicide.
Although
the
endangered
species
LOC
for
estuarine
invertebrates
has
been
exceeded,
there
are
no
listed
species
in
this
group.

The
Agency
is
currently
engaged
in
a
Proactive
Conservation
Review
with
the
Fish
and
Wildlife
Service
(
FWS)
and
the
National
Marine
Fisheries
Service
under
section
7(
a)(
1)
of
the
Endangered
Species
Act.
The
objective
of
this
review
is
to
clarify
and
develop
consistent
processes
for
endangered
species
risk
assessments
and
consultations.
Subsequent
to
the
completion
of
this
process,
the
Agency
will
reassess
the
potential
effects
of
oxadiazon
use
to
federally
listed
threatened
and
endangered
species.
At
that
time
the
Agency
will
also
consider
any
regulatory
changes
recommended
in
the
RED
that
are
being
implemented.
Until
such
time
as
this
analysis
is
completed,
the
overall
environmental
effects
mitigation
strategy
articulated
in
this
document
and
any
County
Specific
Pamphlets
described
in
section
IV
of
the
RED
which
address
oxadiazon,
will
serve
as
interim
protection
measures
to
reduce
the
likelihood
that
endangered
and
threatened
species
may
be
exposed
to
oxadiazon
at
levels
of
concern.
35
IV.
Risk
Management,
Reregistration
and
Tolerance
Reassessment
Decision
A.
Determination
of
Reregistration
Eligibility
Section
4(
g)(
2)(
A)
of
FIFRA
calls
for
the
Agency
to
determine,
after
submission
of
relevant
data
concerning
an
active
ingredient,
whether
or
not
products
containing
the
active
ingredient
are
eligible
for
reregistration.
The
Agency
has
previously
identified
and
required
the
submission
of
the
generic
(
i.
e.,
active
ingredient­
specific)
data
required
to
support
reregistration
of
products
containing
oxadiazon
as
an
active
ingredient.
The
Agency
has
completed
its
review
of
these
generic
data,
and
has
determined
that
the
data
are
sufficient
to
support
reregistration
of
all
products
containing
oxadiazon
provided
that
certain
data
gaps
are
addressed,
the
risk
reduction
measures
outlined
in
this
document
are
adopted
and
labels
are
amended
to
implement
these
measures.
Appendix
B
identifies
the
generic
data
requirements
that
the
Agency
reviewed
as
part
of
its
determination
of
reregistration
eligibility
of
oxadiazon.

These
data
were
sufficient
to
allow
the
Agency
to
determine
that
oxadiazon
can
be
used
without
resulting
in
unreasonable
adverse
effects
to
humans
and
the
environment.
The
Agency,
therefore,
finds
that
all
products
containing
oxadiazon
as
the
active
ingredient
are
eligible
for
reregistration,
provided
specified
changes
are
made
to
the
label.
Actions
needed
to
reregister
particular
products
are
addressed
in
Section
V
of
this
document.
Those
actions
are
the
result
of
risk
management
steps
summarized
in
Chapter
4.
The
Agency
concludes
that
these
label
changes
address
the
current
risk
estimates
and
reflect
the
use
of
all
acceptable
data
available
at
this
time
together
with
uncertainty
factors
where
data
gaps
exist.

The
Agency
may
take
appropriate
regulatory
action
if
new
information
comes
to
the
Agency's
attention
regarding
the
reregistration
of
oxadiazon.
The
Agency
may
also
require
the
submission
of
additional
data
(
1)
to
support
the
registration
of
products
containing
oxadiazon,
(
2)
if
the
data
requirements
for
registration
change,
or
(
3)
if
the
guidelines
for
generating
such
data
change.

B.
Tolerance
Reassessment
With
respect
to
tolerances
for
oxadiazon,
there
have
been
no
active
food­
use
registrations
since
1991.
The
tolerance
for
rice
straw
was
revoked
as
of
the
July
1,
2001
revision
to
40
CFR
180.346.
In
a
confirmatory
letter
to
EPA,
dated
January
24,
2001,
the
registrant
maintained
its
previous
position
that
it
would
not
support
the
sixteen
remaining
oxadiazon
tolerances.
Therefore,
effective
April
24,
2003,
EPA
revoked
all
the
tolerances
in
40
CFR
180.346
for
the
combined
residues
of
the
herbicide
oxadiazon
and
its
metabolites
in
the
following
commodities:
in
or
on
milk;
cattle,
fat;
cattle,
meat;
cattle,
meat
byproducts;
goats,
fat;
goats,
meat;
goats,
meat
byproducts;
hogs,
fat;
hogs,
meat;
hogs,
meat
byproducts;
horses,
fat;
horses,
meat;
horses,
meat
byproducts;
sheep,
fat;
sheep,
meat;
and
sheep,
meat
byproducts.
In
addition,
because
EPA
determined
on
April
21,
2002
that
there
is
no
reasonable
expectation
of
finite
residues
of
oxadiazon
and
its
metabolites
in
or
on
meat,
milk,
poultry,
and
egg
commodities,
the
sixteen
associated
tolerances
for
livestock
commodities
were
considered
by
the
Agency
to
no
longer
be
needed
under
40
CFR
180.6(
a)(
3).
Therefore,
on
June
3,
2002,
the
Agency
considered
the
FQPA
safety
finding
to
be
met
and
counted
the
sixteen
oxadiazon
livestock
tolerances
as
reassessed.
There
are
no
CODEX,
Canadian,
or
Mexican
tolerances
for
oxadiazon
residues.
36
C.
Regulatory
Position
1.
FQPA
and
Aggregate
Risk
Given
that
all
tolerances
for
oxadiazon
have
been
revoked,
this
pesticide
no
longer
falls
under
the
scope
of
FQPA.
As
such,
no
quantitative
aggregate
assessment
of
risk
from
dietary
and
residential
exposures
was
completed
as
part
of
the
reregistration
process.
EPA
has
qualitatively
evaluated
the
likelihood
of
combined
exposures
for
the
general
population,
including
children.
Because
of
the
relatively
low
volume
of
use
of
oxadiazon
on
sites
other
than
golf
courses,
its
specialized
use
pattern,
and
its
relatively
high
cost,
neither
concurrent
nor
aggregate
exposures
from
different
sources
of
oxadiazon
are
likely.
If
EPA
receives
a
petition
for
food/
feed
uses
and/
or
tolerances,
EPA
will
perform
an
FQPA
evaluation
at
that
time.

2.
Endocrine
Disruptor
Effects
EPA
is
required
under
the
FFDCA,
as
amended
by
FQPA,
to
develop
a
screening
program
to
determine
whether
certain
substances
(
including
all
pesticide
active
and
other
ingredients)
"
may
have
an
effect
in
humans
that
is
similar
to
an
effect
produced
by
a
naturally
occurring
estrogen,
or
other
such
endocrine
effects
as
the
Administrator
may
designate."
Following
recommendations
of
its
Endocrine
Disruptor
Screening
and
Testing
Advisory
Committee
(
EDSTAC),
EPA
determined
that
there
was
scientific
basis
for
including,
as
part
of
the
program,
the
androgen
and
thyroid
hormone
systems,
in
addition
to
the
estrogen
hormone
system.
EPA
also
adopted
EDSTAC's
recommendation
that
EPA
include
evaluations
of
potential
effects
in
wildlife.
For
pesticides,
EPA
will
use
FIFRA
and,
to
the
extent
that
effects
in
wildlife
may
help
determine
whether
a
substance
may
have
an
effect
in
humans,
FFDCA
authority
to
require
the
wildlife
evaluations.
As
the
science
develops
and
resources
allow,
screening
of
additional
hormone
systems
may
be
added
to
the
Endocrine
Disruptor
Screening
Program
(
EDSP).

When
the
appropriate
screening
and/
or
testing
protocols
being
considered
under
the
EDSP
have
been
developed,
oxadiazon
may
be
subject
to
additional
screening
and/
or
testing
to
better
characterize
effects
related
to
endocrine
disruption.

3.
Cumulative
Risks
For
the
purposes
of
this
risk
assessment,
the
Agency
has
assumed
that
oxadiazon
does
not
share
a
common
mechanism
of
toxicity
with
other
oxadiazoles
or
carcinogenic
chemicals.

4.
Benefits
Assessment
The
EPA
has
concluded
that
there
are
no
suitable
selective
pre­
emergence
alternatives
to
oxadiazon
currently
available.
Oxadiazon
is
expensive
in
comparison
to
other
goosegrass
controls,
but
those
controls
are
not
as
selective,
as
they
kill
non­
target
plants
as
well.
Because
oxadiazon
is
37
expensive
(
estimated
$
100
­
$
200
per
acre
in
2003),
it
is
expected
that
mainly
high­
end
golf
courses
are
going
to
use
the
herbicide.

D.
Tolerance
Summary
All
tolerances
for
oxadiazon
have
been
revoked.
No
maximum
residue
limits
for
oxadiazon
have
been
established
by
Codex
for
any
agricultural
commodities.
Therefore,
there
are
no
issues
regarding
compatibility
with
respect
to
U.
S.
tolerances.

E.
Human
Health
Risk
Mitigation
1.
Dietary
(
Drinking
Water)
Risk
Mitigation
Screening­
level
estimates
(
EECs)
of
potential
drinking
water
exposure
from
ground
water
sources
do
not
exceed
the
acute
or
chronic
(
non­
cancer
and
cancer)
DWLOC
values,
and
therefore,
are
not
of
concern.
However,
exposure
from
surface
water
sources
after
application
to
golf
courses
is
potentially
of
concern
for
chronic
non­
cancer
and
chronic
cancer
dietary
risk.

The
Tier
II
modeled
estimate
of
average
concentrations
in
surface
water
associated
with
the
use
of
oxadiazon
on
golf
courses
is
56
ppb.
That
value
exceeds
the
Agency's
level
of
concern
by
100­
fold.
However,
it
should
be
noted
that
this
estimate
was
derived
using
an
assumption
that
oxadiazon
is
applied
as
a
wettable
powder
formulation
(
i.
e.,
applied
as
a
spray),
and
therefore
includes
a
value
for
spray
drift
into
water
bodies.
However,
the
predominant
formulation
for
oxadiazon
applied
to
golf
course
turf
is
granular,
and
typically
the
herbicide
is
encapsulated
in
a
granular
fertilizer.

Additionally,
the
Tier
II
assessment
of
EECs
used
an
annual
application
rate
of
8
lbs
ai/
A.
Discussions
with
the
oxadiazon
registrant
and
golf
course
personnel
indicate
that
the
cost
of
oxadiazon
limits
the
frequency
of
use
of
the
8
lbs
ai/
A
annual
rate
to
areas
with
heavy
weed
infestation,
as
might
be
encountered
during
the
first
year
during
which
golf
course
turf
is
being
established.
Following
the
first
year
at
the
8
lbs
ai/
A
rate,
more
typical
rates
of
2­
6
lbs
ai/
A/
yr
are
used
on
established
turf.
The
registrant
has
agreed
to
set
the
maximum
application
rate
at
6
lbs
a.
i./
A/
yr
(
typically
applied
in
multiple
applications)
except
in
areas
of
heavy
weed
infestation.
In
areas
with
heavy
weed
infestation,
the
maximum
application
rate
will
be
8
lbs
a.
i./
A/
yr.
The
maximum
single
application
rate
is
4
lbs
ai/
A.

When
the
typical
annual
maximum
application
rate
(
6
lbs
ai/
A)
and
the
impact
of
a
granular
formulation
versus
a
wettable­
powder
formulation
are
considered,
the
surface
water
EEC
decreases
to
approximately
25
ppb.
This
value
is
below
the
level
of
concern
for
chronic
non­
cancer
risk,
but
is
still
50­
fold
greater
than
the
chronic
cancer
DWLOC.

Limited
water
monitoring
data
from
three
states
indicate
that
oxadiazon,
though
detected
in
surface
water
bodies,
is
present
at
concentrations
below
the
Agency's
level
of
concern.
Additionally,
preliminary
data
from
a
study
designed
to
measure
pesticide
concentrations
in
golf
course
runoff,
and
performed
under
an
EPA
grant,
suggest
that
oxadiazon
concentrations
in
surfacesourced
drinking
water
will
not
exceed
the
Agency's
level
of
concern
(
DWLOC
=
0.49
ppb).
38
One
factor
that
may
be
contributing
to
the
apparent
discrepancy
between
model
estimates
and
measured
concentrations
is
the
percent
crop
area
(
PCA)
value.
This
value
is
used
in
the
PRZM/
EXAMS
models
as
the
percentage
of
land
area,
within
a
specific
watershed,
that
is
made
up
of
the
crop
of
interest,
in
this
case
golf
course
turf.
In
characterizing
oxadiazon,
the
Agency
has
used
a
PCA
value
of
94%
to
account
for
the
land
area
of
a
typical
golf
course
that
is
tees
and
greens
(
4%),
fairway
(
23%)
and
rough
(
67%).
Using
the
94%
PCA
value
results
in
an
upper­
bound
estimate
of
the
potential
environmental
concentrations
of
oxadiazon
if
94%
of
a
watershed
was
golf
course
turf,
and
on
each
golf
course
100%
of
available
turf
was
treated
with
oxadiazon
at
the
maximum
application
rate.

The
registrant
has
submitted
Geographic
Information
System
(
GIS)
data
that
localizes
golf
courses
in
Florida,
along
with
watershed
boundary
information.
That
data
suggests
that
the
upper
bound
PCA
for
golf
course
turf
in
Florida
is
substantially
less
than
94%.
The
Agency
took
that
information
into
account
when
it
concluded
that
although
oxadiazon
is
eligible
for
reregistration,
water
monitoring
studies
are
required.

As
noted
above,
the
currently
supported
maximum
rate
of
8
lbs
ai/
A/
year
might
be
applied
to
turf
with
heavy
weed
infestation
during
the
first
year
in
which
a
golf
course
is
being
established.
Thereafter,
because
of
the
expense
of
treating
with
oxadiazon,
typical
application
rates
of
2­
6
lbs
ai/
A
would
be
used,
depending
on
location.
For
most
locations,
a
single
2­
4
lb
ai
application
per
year
is
sufficient
to
control
goosegrass.
However,
in
the
extreme
southern
locations
(
e.
g.,
south
Florida)
where
the
growing
season
is
continuous,
two
applications
of
3
lbs
ai/
A
are
typical.
Similarly,
economic
factors
limit
the
use
of
oxadiazon
on
golf
course
roughs.
Since
roughs
make
up
approximately
67%
of
golf
course
turf
area,
the
limited
use
on
roughs
can
have
a
great
impact
on
the
total
pounds
applied.

The
estimated
EECs
in
surface
water
were
derived
using
the
high­
end
values
discussed
above,
in
addition
to
others
that,
when
combined,
lead
to
an
upper­
bound
estimate
of
risk.
For
example,
when
estimating
the
chronic
cancer
risk,
the
assumption
is
made
that
an
individual
drinks
from
the
same
water
source
every
day
for
a
70­
year
lifetime.
After
characterizing
the
assumptions
used
to
derive
the
estimates
of
oxadiazon
concentrations
in
drinking
water,
the
Agency
has
concluded
that
the
actual
concentrations
of
oxadiazon
in
drinking
water
are
likely
to
be
below
the
Agency's
level
of
concern.
To
confirm
the
absence
of
chronic
exposure
to
oxadiazon
in
drinking
water
at
concentrations
that
exceed
the
Agency's
cancer
level
of
concern,
the
Agency
is
requiring
the
registrant
to
submit
three
years
of
drinking
water
monitoring
data
collected
from
sites
determined
by
the
Agency
to
be
likely
to
result
in
upper­
bound
exposures,
with
interim
reporting
after
the
first
season.
In
addition
to
providing
real­
world
measures
of
oxadiazon
concentrations
in
drinking
water,
the
monitoring
data
may
prove
to
be
useful
in
on­
going
efforts
to
validate
a
refined
PCA
value
for
turf.
In
the
event
that
interim
data
indicate
concentrations
of
oxadiazon
in
drinking
water
do
exceed
the
Agency's
level
of
concern,
registrants
have
agreed
to
consider
further
mitigation
measures,
such
as,
further
rate
reductions
and
limitations
on
the
areas
of
golf
courses
that
can
be
treated.
Regardless
of
the
outcome
of
the
water
monitoring
study,
the
registrant
has
agreed
to
establish
a
15
foot
"
no
apply"
zone
around
bodies
of
water
that
may
serve
as
sources
of
drinking
water.
39
2.
Non­
occupational
Post­
application
Risk
Mitigation
a.
Non­
cancer
risk
mitigation
Because
oxadiazon
is
not
available
for
sale
to
homeowners,
residential
handler
scenarios
do
not
exist.
All
of
the
non­
cancer
post­
application
risk
scenarios
for
adults
and
toddlers
had
short­
term
and
intermediate­
term
dermal
MOEs
greater
than
100.
Therefore,
no
mitigation
measures
are
needed.

Estimated
incidental,
oral
short­
term
exposures
("
hand­
to­
mouth")
for
children
had
an
MOE
of
100
using
the
TTR
default
values
from
the
residential
SOP.
When
the
TTR
data
from
the
submitted
oxadiazon
study
were
used,
the
MOEs
were
90
and
240
for
non­
irrigated
and
irrigated
dormant
grass,
respectively.
The
MOE
of
90
for
non­
irrigated
grass
does
not
meet
or
exceed
the
target
value
of
100,
and
is
therefore
potentially
of
concern.
However,
the
risk
estimate
can
be
considered
to
be
an
upper­
bound
for
several
reasons:
1)
the
submitted
TTR
study
data
were
obtained
using
the
wettable
powder
formulation,
whereas
the
formulation
more
likely
to
be
used
on
residential
turf
is
granular
oxadiazon.
The
granule
size
for
a
typical
end­
use
product,
Ronstar
G,
is
20/
50
Mesh,
or
300­
850
microns.
In
all
products,
the
formulated
granules
are
designed
to
fall
below
the
grass
canopy
into
the
thatch
layer.
If
used
according
to
label
directions,
it
is
unlikely
that
oxadiazon
granules
would
be
accessible
to
a
child.
According
to
the
registrant,
for
best
results
oxadiazon
granules
should
be
watered­
in
as
soon
as
is
practical
following
application.
Watering­
in
the
granules
will
carry
them
further
into
the
thatch
layer,
and
will
further
decrease
the
likelihood
for
exposure.
When
compared
to
values
for
granular
formulations,
TTR
values
are
generally
10­
100
fold
greater
for
liquid
formulations;
2)
the
highest
mean
residues
from
the
Jazzercize
study
described
above
were
used
to
estimate
exposures
between
zero
and
one
days
after
treatment,
and
the
hand­
to
mouth
risk
estimates
were
generated
at
those
high­
end
exposure
levels;
and
3)
the
risk
estimates
were
generated
assuming
20
hand­
to
mouth
events
per
hour
for
a
two
hour
duration.
That
value
was
taken
from
observations
of
children
in
an
indoors
setting,
and
is
likely
an
overestimate
when
considering
an
outdoor
scenario.

Given
that
the
estimate
of
risk
from
incidental,
oral
short­
term
exposures
("
hand­
to­
mouth")
for
children
resulted
from
the
combined
use
of
these
high­
end
exposure
assumptions,
the
EPA
concludes
that
the
risk
estimate
that
results
in
an
MOE
of
90
for
non­
irrigated
dormant
grass
is
likely
to
be
an
overestimate
and
not
a
cause
for
concern.
No
mitigation
measures
are
required
to
address
the
non­
cancer
chronic
risk
from
non­
occupational
post­
application
exposure.

MOEs
were
not
calculated
for
the
incidental
ingestion
of
oxadiazon
granules
because,
as
discussed
above,
the
very
small
granules
would
not
be
available
on
the
lawn
surface
and
thus
not
accessible
to
children.
It
is
thought,
therefore,
that
the
incidental
ingestion
of
granules
is
not
likely
to
be
a
cause
for
concern.

b.
Cancer
risk
mitigation
The
cancer
risks
for
all
adult
post­
application
exposures
were
between
6.22
x
10­
6
and
7.51
x
10­
7.
Exposure
scenarios
ranged
from
adults
involved
in
low
exposure
activities
on
turf
such
as
mowing
with
a
push
mower
(
Transfer
Coefficient
=
500
cm2/
hour;
cancer
risk
=
7.51
x
10­
7)
and
golfing
(
Transfer
Coefficient
=
500
cm2/
hour;
cancer
risk
=
1.50
x
10­
6)
to
adults
involved
in
high
40
exposure
activities
on
turf
such
as
heavy
yard
work
(
Transfer
Coefficient
=
14,500
cm2/
hr;
cancer
risk
=
6.22
x
10­
6
on
non­
irrigated
turf).
The
cancer
risk
estimates
were
based
on
several
upperbound
assumptions,
including:
1)
the
maximum
application
rate
of
4
lbs
ai/
A;
2)
an
exposure
concentration
based
on
the
residue
concentration
at
day
0­
1
after
treatment
with
a
wettable
powder
formulation;
and
3)
three
exposures
to
oxadiazon­
treated
turf
per
year
for
35
years.

Those
assumptions
are
thought
to
be
upper­
bound,
since:
1)
although
the
maximum
single
application
rate
is
4
lbs
ai/
A,
the
typical
application
rate
for
residential
and
golf
course
turf
is
2­
3
lbs
ai/
A;
2)
based
on
residue
data,
the
dissipation
half­
life
for
oxadiazon
on
turf
is
approximately
1.5
days.
As
such,
it
is
unlikely
that
an
individual
would
golf
or
perform
heavy
yard
work,
and
thereby
be
exposed
to
the
maximum
residue
concentration,
each
time
oxadiazon
is
applied
over
a
35
year
period;
and
3)
typically
oxadiazon
is
applied
once
per
year
to
residential
turf,
and
twice
per
year
to
golf
course
turf
in
areas
with
extended
growing
seasons
(
e.
g.
south
Florida).

Given
the
combination
of
upper­
bound
assumptions,
as
described
above,
the
Agency
concludes
that
the
cancer
risk
equation,
as
used
in
the
assessment
of
cancer
risk
from
postapplication
non­
occupational
exposure
to
oxadiazon,
is
likely
to
result
in
an
overestimate
of
risk.
No
mitigation
measures
are
required
to
address
the
risk
of
cancer
from
post­
application,
nonoccupational
exposure
to
oxadiazon.

3.
Occupational
Risk
Mitigation
a.
Handlers
(
1.)
Non­
cancer
risk
mitigation
The
results
of
the
short
and
intermediate­
term
handler
assessments
are
presented
in
Table
5
and
indicate
that
all,
but
one,
potential
non­
cancer
exposure
scenarios
provide
at
least
one
application
rate
with
a
total
MOE(
s)
greater
than
or
equal
to
100
at
either
the
baseline
(
i.
e.,
long
pants,
long
sleeved
shirts,
no
gloves)
using
open
systems,
PPE
(
i.
e.,
long
pants,
long
sleeved
shirts,
and
chemical
resistant
gloves
while
using
open
systems),
or
using
engineering
controls
(
i.
e.,
closed
systems).
The
only
exception,
with
the
feasible
level
of
mitigation,
is
application
of
wettable
powder
formulations
with
a
low
pressure
handwand,
with
an
MOE
of
46.

This
scenario
assumes
that
a
worker
would
treat
five
acres
per
day
using
a
low­
pressure
hand
wand.
The
highest
volume
use
of
a
low­
pressure
hand
wand
applicator
is
likely
to
be
on
nonturf
areas
of
golf
courses
(
e.
g.,
in
areas
under
and
around
trees,
shrubs,
and
ornamentals).
According
to
golf
course
personnel,
a
typical
worker
would
likely
cover
a
maximum
of
one
acre
a
day
when
applying
oxadiazon
with
a
low­
pressure
hand
wand.
The
total
area
on
a
golf
course
likely
to
be
treated
with
a
low­
pressure
handwand
is
approximately
two
acres.
Using
a
conservative
assumption
that
in
a
worst­
case
scenario
a
worker
might
treat
three
acres
in
a
day,
and
considering
PPE,
the
MOE
for
this
scenario
would
increase
to
the
target
MOE
of
100.
The
Agency
concludes
that
the
non­
cancer
risk
does
not
exceed
the
Agency's
level
of
concern,
therefore,
no
mitigation
is
required
to
address
the
non­
cancer
risks
from
occupational
handler
exposures
to
oxadiazon.
41
(
2.)
Cancer
risk
mitigation
The
cancer
risk
assessments
for
handlers
used
baseline
exposure
scenarios
and,
as
needed,
increasing
levels
of
risk
mitigation
(
PPE
and
engineering
controls)
to
achieve
cancer
risks
that
would
be
considered
of
no
concern.
According
to
Agency
policy,
the
level
of
concern
for
cancer
risks
from
occupational
exposure
to
pesticides
ranges
from
1.0
x
10­
4
to
1.0
x
10­
6,
depending
on
the
feasibility,
availability,
and
cost
of
various
mitigation
options.

Based
on
the
scenarios
identified
previously,
the
Agency
estimates
that
the
risk
of
developing
cancer
from
occupational
dermal
and
inhalation
exposures
to
oxadiazon
ranges
from
1.7
x
10­
2
to
4.7
x
10­
7
during
"
baseline"
conditions
(
i.
e.,
long
pants,
long­
sleeves,
no
gloves).
Cancer
risk
ranges
from
1
x
10­
3
to
1
x
10­
7
when
personal
protective
equipment
(
PPE)
(
i.
e.,
long
pants,
long­
sleeved
shirt,
and
chemical­
resistant
gloves)
was
used.
The
Agency
estimates
that
cancer
risk
decreases
to
a
range
of
5
x
10­
5
to
1
x
10­
8
with
engineering
controls.
Engineering
controls
included
the
use
of
chemical­
resistant
gloves
along
with
water­
soluble
packaging
for
wettable
powder
formulations.
Overall
these
data
suggest
that
when
PPE
and
engineering
controls
are
used,
none
of
the
evaluated
scenarios
have
cancer
risks
that
exceed
1.0
x
10­
4
.
Therefore,
the
Agency
is
requiring
that
wettable
powder
formulations
of
oxadiazon
be
packaged
in
water­
soluble
packaging.
In
addition,
wettable­
powder
product
labels
will
require
that
handlers
wear
chemical­
resistant
gloves
in
addition
to
long
pants
and
a
long­
sleeved
shirt
during
mixing/
loading/
applying
scenarios.

b.
Post­
application
The
Agency
uses
the
term
"
post­
application"
to
describe
those
individuals
who
can
be
exposed
to
pesticides
when
entering
areas
previously
treated
with
pesticides
and
performing
certain
jobs,
tasks
or
activities.
This
is
also
often
referred
to
as
reentry
exposure.
The
Agency
has
determined
that
there
are
potential
post­
application
exposures
to
individuals
re­
entering
oxadiazon
treated
areas
for
the
purpose
of:

Roadsides:
mowing
Bermuda
grass
rights­
of­
way:
mowing
Sod
farms:
mowing,
hand­
weeding,
and
harvesting
Golf­
course
turfgrass:
mowing
and
hand­
weeding
For
short­
and
intermediate­
term
non­
cancer
risks,
mowing
(
e.
g.,
golf
courses,
roadsides,
and
sod
farms)
and
harvesting
(
e.
g.,
sod
farms)
scenarios
were
considered
for
post­
application
occupational
exposure.
Calculations
for
mowing
activities
resulted
in
MOEs
of
1000.

Calculations
for
hand­
weeding
and
harvesting
activities
on
golf
courses
and
sod
farms
resulted
in
MOEs
of
30,
less
than
the
target
MOE
of
100
for
post­
application
occupational
exposures.
However,
the
values
used
to
calculate
the
hand­
weeding
and
harvesting
MOEs
likely
result
in
an
over­
estimate
of
risk.
For
example,
the
calculation
for
hand­
weeding
on
golf
courses
assumes
that
a
worker
would
perform
that
activity
for
8
hours/
day
on
the
day
following
application
of
oxadiazon
at
the
maximum
application
rate.
Based
on
the
quality
of
turf
present
on
high­
end
golf
courses
most
likely
to
apply
oxadiazon,
it
is
unlikely
that
golf
course
personnel
would
spend
more
than
one
or
two
hours
per
day
performing
hand­
weeding
activities.
The
Agency
concludes
that
the
risk
from
post­
application
hand­
weeding
of
golf
courses
does
not
exceed
the
level
of
concern.
No
mitigation
measures
will
be
required.
42
With
respect
to
risk
concerns
from
post­
application
activities
on
sod
farms,
while
the
oxadiazon
label
does
not
prohibit
its
use,
the
cost
of
treating
with
oxadiazon
is
prohibitive.
Due
to
its
cost,
less
than
20%
of
sod
farmers
are
using
oxadiazon.
Those
sod
farmers
that
are
using
oxadiazon
apply
it
as
a
wettable
powder
formulation
at
2­
3
lbs
ai/
A
immediately
after
planting
(
aka
sprigging)
to
control
weeds
during
sod
establishment.
Harvesting
activities
occur
six
to
nine
months
following
application,
depending
on
the
variety
of
grass
being
grown.
As
noted
above,
the
scenario
with
respect
to
hand­
weeding
assumes
an
8­
hour
workday,
which
is
unlikely.
The
foliar
dissipation
half
life
for
oxadiazon
(
approximately
1.5
days)
is
such
that
after
three
days
post­
application,
the
MOE
would
rise
above
100.
Therefore,
the
Agency
concludes
that
the
risk
from
post­
application
harvesting
on
sod
farms
does
not
exceed
the
level
of
concern.
No
mitigation
measures
will
be
required.

Cancer
risks
for
occupational
postapplication
scenarios
were
estimated
not
to
exceed
EPA's
level
of
concern.

4.
Inhalation
Toxicity
and
Exposure
Uncertainties
The
Agency
is
concerned
about
potential
inhalation
risk
to
applicators
using
wettable
powder
formulations.

The
following
confirmatory
data
are
required:

°
870.3465
28­
day
inhalation
toxicity
study
F.
Environmental
Risk
Mitigation
1.
Terrestrial
Organism
Risk
Mitigation
Using
the
EC
formulation,
at
application
rates
of
2.0
­
4.0
lbs
ai/
A
(
2
applications/
6
months)
and
two
split
applications
(
1.0
lbs
ai/
A
applied
4
times/
6
months
and
1.3
lbs
ai/
A
applied
3
times/
6
months),
model
estimates
indicate
that
oxadiazon
may
pose
a
chronic
risk
to
mammals
that
eat
plants
and
insects.
RQs
range
from
1
to
5.

The
Agency
does
not
currently
perform
screening­
level
assessments
of
chronic
risk
to
birds
and
mammals
from
granular
formulations.
Here,
the
emulsifiable
concentrate
(
EC)
formulation
was
used
to
estimate
chronic
risk
to
birds
and
mammals.
The
emulsifiable
concentrate
formulation
likely
represents
an
upper­
bound
scenario
in
terms
of
oxadiazon
exposure
to
birds
and
mammals
that
might
feed
on
grasses
and
insects
on
golf
course
turf.
Approximately
90%
of
oxadiazon
is
applied
as
a
granular
formula.
Unlike
the
residue
that
would
remain
on
grass
and
foliage
following
a
spray
application,
granules
of
oxadiazon
would
settle
to
the
thatch
or
soil
layer.
This
is
especially
true
when
the
turf
is
watered
following
application,
as
many
end­
product
labels
currently
recommend.
The
granule
size
for
a
typical
end­
use
product,
Ronstar
G,
is
20/
50
Mesh,
or
300­
850
microns.
In
all
products,
the
formulated
granules
are
designed
to
fall
below
the
grass
canopy.
If
used
according
to
label
directions,
it
is
unlikely
that
oxadiazon
granules
would
be
accessible
to
birds
and
mammals
that
feed
on
grasses.
According
to
the
registrant,
for
best
results
oxadiazon
granules
should
be
wateredin
as
soon
as
is
practical
following
application.
Watering­
in
the
granules
will
carry
them
further
into
43
the
thatch
layer,
and
will
further
decrease
the
likelihood
for
exposure.
As
such,
the
amount
of
oxadiazon
available
for
ingestion
by
birds
and
mammals
is
likely
to
be
less
than
was
used
in
calculating
the
RQ
values,
and
it
is
likely
that
the
actual
exposures
would
result
in
RQ
values
significantly
less
than
the
range
of
1
to
5
obtained
by
assessing
the
emulsifiable
concentrate
formulation.
The
Agency
concludes
that
the
chronic
risk
to
terrestrial
organisms
from
exposure
to
oxadiazon
does
not
exceed
the
level
of
concern.
No
mitigation
measures
will
be
required.

2.
Aquatic
Organism
Risk
Mitigation
a.
Fish
and
Invertebrates
Tier
1
model
estimates
of
oxadiazon
concentrations
in
water
suggest
that
acute
exposures
pose
low
risk
to
fish
(
RQ
=
0.1­
0.2)
and
invertebrates
(
RQ=
0.3
­
0.5);
however,
there
is
some
uncertainty
about
the
role
of
sunlight
on
oxadiazon
toxicity
in
clear,
shallow
bodies
of
water.
GENEEC
model
outputs
suggest
that
chronic
exposure
to
oxadiazon
may
result
in
risk
to
freshwater
and
estuarine/
marine
fish.
RQs
range
from
94
to
139
(
freshwater)
and
55
to
81
(
estuarine/
marine),
depending
on
application
rate
and
formulation.
Likewise,
model
estimates
indicate
that
chronic
exposure
to
oxadiazon
may
result
in
chronic
risk
to
freshwater
and
estuarine/
marine
invertebrates.
RQs
range
from
2.9
to
4.5
(
freshwater)
and
23
to
37
(
estuarine/
marine),
depending
on
application
rate
and
formulation.

The
Tier
I
GENEEC
model
60­
day
EEC
of
oxadiazon
in
surface
water
following
two
fourpound
applications
of
granular
oxadiazon
was
142
ppb.
However,
the
conservative
Tier
I
model
does
not
account
for
the
effect
of
established
golf
course
turf
on
reducing
run­
off.
Tier
II
PRZM/
EXAMS
estimates
of
EECs
for
drinking
water,
although
not
directly
applicable
to
the
risk
assessment
for
aquatic
organisms,
suggest
that
the
golf
course
scenario
greatly
reduces
run­
off.
Tier
II
estimates
of
oxadiazon
concentrations
in
surface­
sourced
drinking
water
were
approximately
sixfold
lower
than
the
Tier
I
GENEEC
estimate
described
above.
It
is
reasonable
to
believe
that
Tier
II
EECs
for
a
pond
scenario
would
likewise
be
reduced.

In
order
to
further
assess
the
risk
to
fish
and
invertebrates
from
oxadiazon
exposure,
the
Agency
is
requiring
that
the
registrant
submit
toxicity
data
from
early­
stage
estuarine
fish
studies
and
life
cycle
estuarine/
marine
invertebrate
studies.
Also,
enhanced
toxicity
through
exposure
to
high
levels
of
solar
radiation
may
increase
toxic
risk
to
aquatic
organisms
that
inhabit
small,
shallow
water
bodies.
Therefore,
EPA
is
requiring
a
study
on
the
phototoxicity
of
oxadiazon
in
fathead
minnows.

b.
Benthic
Organisms
Oxadiazon
residues
can
accumulate
in
sediments
and
may
increase
the
risk
from
chronic
exposure
of
benthic
and
epibenthic
organisms
(
aquatic
organisms
that
live
in
or
on
the
sediment)
to
the
pesticide.
In
order
to
better
understand
this
potential
risk,
EPA
is
requiring
appropriate
sediment
toxicity
testing,
both
acute
and
chronic,
on
this
compound.
44
c.
Aquatic
Plants
For
aquatic
plants,
RQs
for
acute
exposure
are
relatively
high,
ranging
from
1.1
to
4.2
for
duckweed,
and
8.5
to
33
for
diatoms,
depending
on
application
rates
and
formulation.

The
Tier
I
GENEEC
model
60­
day
EEC
of
oxadiazon
in
surface
water
following
two
fourpound
applications
of
granular
oxadiazon
was
142
ppb.
However,
the
conservative
Tier
I
model
does
not
account
for
the
effect
of
established
golf
course
turf
on
reducing
sediment
run­
off.
Tier
II
PRZM/
EXAMS
estimates
of
EECs
for
drinking
water,
although
not
directly
applicable
to
the
risk
assessment
for
aquatic
organisms,
suggest
that
the
golf
course
scenario
greatly
reduces
run­
off.
Tier
II
estimates
of
oxadiazon
concentrations
in
surface­
sourced
drinking
water
were
approximately
sixfold
lower
than
the
Tier
I
GENEEC
estimate
described
above.
It
is
reasonable
to
assume
that
Tier
II
EECs
for
a
pond
scenario
would
likewise
be
reduced.

Currently,
the
Agency
does
not
have
sufficient
data
with
respect
to
the
toxic
effects
of
oxadiazon
on
aquatic
organisms
on
which
to
base
an
effective
risk
management
strategy.
To
help
clarify
the
risks
to
aquatic
plant
species,
the
Agency
is
requiring
that
the
registrant
submit
the
following
studies:
aerobic
aquatic
metabolism,
seedling
germination/
emergence,
vegetative
vigor,
and
aquatic
phototoxicity.

G.
Other
Labeling
Requirements
1.
Endangered
Species
Statement
The
Agency
has
developed
the
Endangered
Species
Protection
Program
to
identify
pesticides
whose
use
may
cause
adverse
impacts
on
endangered
and
threatened
species,
and
to
implement
mitigation
measures
that
address
these
impacts.
The
Endangered
Species
Act
requires
federal
agencies
to
ensure
that
their
actions
are
not
likely
to
jeopardize
listed
species
or
adversely
modify
designated
critical
habitat.
To
analyze
the
potential
of
registered
pesticide
uses
to
affect
any
particular
species,
EPA
puts
basic
toxicity
and
exposure
data
developed
for
REDs
into
context
for
individual
listed
species
and
their
locations
by
evaluating
important
ecological
parameters,
pesticide
use
information,
the
geographic
relationship
between
specific
pesticide
uses
and
species
locations,
and
biological
requirements
and
behavioral
aspects
of
the
particular
species.
This
analysis
will
take
into
consideration
any
regulatory
changes
recommended
in
this
RED
that
are
being
implemented
at
this
time.
A
determination
that
there
is
a
likelihood
of
potential
impact
to
a
listed
species
may
result
in
limitations
on
use
of
the
pesticide,
other
measures
to
mitigate
any
potential
impact,
or
consultations
with
the
Fish
and
Wildlife
Service
and/
or
the
National
Marine
Fisheries
Service
as
necessary.

The
Endangered
Species
Protection
Program
as
described
in
a
Federal
Register
notice
(
54
FR
27984­
28008,
July
3,
1989)
is
currently
being
implemented
on
an
interim
basis.
As
part
of
the
interim
program,
the
Agency
has
developed
County
Specific
Pamphlets
that
articulate
many
of
the
specific
measures
outlined
in
the
Biological
Opinions
issued
to
date.
The
Pamphlets
are
available
for
voluntary
use
by
pesticide
applicators
on
EPA's
website
at
www.
epa.
gov/
espp.
A
final
Endangered
Species
Protection
Program,
which
may
be
altered
from
the
interim
program,
has
been
proposed
for
public
comment
in
the
Federal
Register
(
67
FR
#
231,
December
2,
2002;
edocket
OPP­
2002­
0311.)
45
2.
Spray
Drift
Management
Approximately
90%
of
oxadiazon
is
applied
as
a
granular
formulation,
for
which
spray
drift
is
not
a
concern.
The
approximately
10%
of
oxadiazon
that
is
applied
as
a
spray
using
a
wettable
powder
formulation
is
applied
to
nursery
stock
and
non­
turf
areas
of
golf
courses
using
handheld
sprayers
and
to
sod
farms
using
tractor­
drawn
boom
sprayers.
The
wettable
powder
formulation
is
not
typically
used
around
bodies
of
water,
so
that
the
risk
of
contamination
of
water
with
oxadiazon
as
a
result
of
spray
drift
is
not
of
concern.
No
label
language
is
required
to
address
ecological
or
drinking
water
concerns
that
arise
from
off­
target
drift
from
spray
applications
of
oxadiazon.

To
address
the
risk
to
human
health
associated
with
off­
target
drift
from
spray
applications,
the
following
label
language
is
required
for
oxadiazon
wettable­
powder
products:
"
Do
not
apply
this
product
in
a
way
that
will
contact
workers
or
other
persons
either
directly
or
through
drift."

The
Agency
is
currently
working
with
stakeholders
to
develop
appropriate
generic
label
statements
to
address
off­
target
drift
risk.
Once
this
process
has
been
completed,
oxadiazon
products
may
need
to
be
revised
to
include
this
additional
language.

V.
Actions
Required
of
Registrants
In
order
to
be
eligible
for
reregistration,
registrants
need
to
implement
the
risk
mitigation
measures
outlined
in
Section
IV,
which
include,
among
other
things,
submission
of
the
following:

For
oxadiazon
technical
grade
active
ingredient
products,
registrants
need
to
submit
the
following
items.

Within
90
days
from
receipt
of
the
generic
data
call­
in
(
DCI):

(
1)
completed
response
forms
to
the
generic
DCI
(
i.
e.,
DCI
response
form
and
requirements
status
and
registrant's
response
form);
and
(
2)
submit
any
time
extension
and/
or
waiver
requests
with
a
full
written
justification.

Within
the
time
limit
specified
in
the
generic
DCI:

(
1)
Cite
any
existing
generic
data
which
address
data
requirements
or
submit
new
generic
data
responding
to
the
DCI.

Please
contact
Mark
Seaton
at
703/
306­
0469
with
questions
regarding
generic
reregistration
and/
or
the
DCI.
All
materials
submitted
in
response
to
the
generic
DCI
should
be
addressed:
46
By
US
mail:
By
express
or
courier
service:

Document
Processing
Desk
(
DCI/
SRRD)
Document
Processing
Desk
(
DCI/
SRRD)

Mark
Seaton
Mark
Seaton
US
EPA
(
7508C)
Office
of
Pesticide
Programs
(
7508C)

1200
Pennsylvania
Ave.,
NW
Room
266A,
Crystal
Mall
2
Washington,
DC
20460
1921
Jefferson
Davis
Highway
Arlington,
VA
22202
For
products
containing
the
active
ingredient
oxadiazon,
registrants
need
to
submit
the
following
items
for
each
product.

Within
90
days
from
the
receipt
of
the
product­
specific
data
call­
in
(
PDCI):

(
1)
Complete
response
forms
to
the
PDCI
(
i.
e.,
PDCI
response
form
and
requirements
status
and
registrant's
response
form);
and
(
2)
Submit
any
time
extension
or
waiver
requests
with
a
full
written
justification.

Within
eight
months
from
the
receipt
of
the
PDCI:

(
1)
Two
copies
of
the
confidential
statement
of
formula
(
EPA
Form
8570­
4);

(
2)
A
completed
original
application
for
reregistration
(
EPA
Form
8570­
1).

Indicate
on
the
form
that
it
is
an
"
application
for
reregistration";

(
3)
Five
copies
of
the
draft
label
incorporating
all
label
amendments
outlined
in
Table
15
of
this
document;

(
4)
A
completed
form
certifying
compliance
with
data
compensation
requirements
(
EPA
Form
8570­
34);

(
5)
If
applicable,
a
completed
form
certifying
compliance
with
cost
share
offer
requirements
(
EPA
Form
8570­
32);
and
(
6)
The
product­
specific
data
responding
to
the
PDCI.

Please
contact
Bonnie
Adler
at
(
703)
308­
8523
with
questions
regarding
product
reregistration
and/
or
the
PDCI.
All
materials
submitted
in
response
to
the
PDCI
should
be
addressed:

By
US
mail:
By
express
or
courier
service
only:

Document
Processing
Desk
(
PDCI/
PRB)
Document
Processing
Desk
(
PDCI/
PRB)

Bonnie
Adler
Bonnie
Adler
47
US
EPA
(
7508C)
Office
of
Pesticide
Programs
(
7508C)

1200
Pennsylvania
Ave.,
NW
Room
266A,
Crystal
Mall
2
Washington,
DC
20460
1921
Jefferson
Davis
Highway
Arlington,
VA
22202
A.
Manufacturing
Use
Products
1.
Additional
Generic
Data
Requirements
The
generic
database
supporting
the
reregistration
of
oxadiazon
for
the
eligible
uses
has
been
reviewed
and
determined
to
be
substantially
complete.
The
following
confirmatory
data
are
required:

Guideline
Test
Name
OPPTS
Guideline
No.
Old
Guideline
No.

28­
day
inhalation
toxicity
870.3465
82­
4
Aerobic
Aquatic
Metabolism
835.4300
162­
4
Early­
stage
Estuarine
Fish
850.1400
72­
4(
a)

Life
Cycle
Estuarine/
Marine
Invertebrate
850.1300
850.1350
72­
4(
b)

Seedling
Germination/
Emergence
850.4100
122­
1(
a)

Vegetative
Vigor
850.4150
122­
1(
b)

Seedling
Germination/
Emergence
850.4225
123­
1(
a)

Vegetative
Vigor
850.4250
123­
1(
b)

Aquatic
Phototoxicity
Studies
(
Fathead
minnow)
­­
70­
1
Acute
and
Chronic
Sediment
Toxicity
Testing
­­
70­
1
Water
Monitoring
Study
70­
1
2.
Labeling
for
Manufacturing
Use
Products
To
remain
in
compliance
with
FIFRA,
manufacturing
use
product
(
MUP)
labeling
should
be
revised
to
comply
with
all
current
EPA
regulations,
PR
Notices
and
applicable
policies.
The
MUP
labeling
should
bear
the
labeling
contained
in
the
table
at
the
end
of
this
section.
The
MUP
label
will
explicitly
prohibit
use
of
products
that
do
not
conform
to
Section
V.
B.
2
of
this
document.

B.
End­
Use
Products
48
1.
Additional
Product­
Specific
Data
Requirements
Section
4(
g)(
2)(
B)
of
FIFRA
calls
for
the
Agency
to
obtain
any
needed
product­
specific
data
regarding
the
pesticide
after
a
determination
of
eligibility
has
been
made.
Registrants
must
review
previous
data
submissions
to
ensure
that
they
meet
current
EPA
acceptance
criteria
and
if
not,
commit
to
conduct
new
studies.
If
a
registrant
believes
that
previously
submitted
data
meet
current
testing
standards,
then
the
study
MRID
numbers
should
be
cited
according
to
the
instructions
in
the
Requirement
Status
and
Registrants
Response
Form
provided
for
each
product.

2.
Labeling
for
End­
Use
Products
Labeling
changes
are
necessary
to
implement
measures
outlined
in
Section
V
above.
Specific
language
to
implement
these
changes
is
specified
in
Table
14
at
the
end
of
this
section.
To
remain
in
compliance
with
FIFRA,
end­
use
product
(
EUP)
labeling
should
be
revised
to
comply
with
all
current
EPA
regulations,
PR
Notices
and
applicable
policies.
49
C.
Labeling
Changes
Summary
Table
In
order
to
be
eligible
for
reregistration,
amend
all
product
labels
to
incorporate
the
risk
mitigation
measures
outlined
in
Section
IV.

The
following
table
describes
how
language
on
the
labels
should
be
amended.

Table
14:
Summary
of
Labeling
Changes
for
Oxadiazon
Description
Amended
Labeling
Language
Placement
on
Label
Manufacturing
Use
Products
One
of
these
statements
may
be
added
to
a
label
to
allow
reformulation
of
the
product
for
a
specific
use
or
all
additional
uses
supported
by
a
formulator
or
user
group
"
Only
for
formulation
into
an
herbicide
for
the
following
use(
s)
[
fill
blank
only
with
those
uses
that
are
being
supported
by
MP
registrant].
This
product
may
not
be
formulated
into
products
intended
for
residential
consumer
use.
"
Directions
for
Use
"
This
product
may
be
used
to
formulate
products
for
specific
use(
s)
not
listed
on
the
MP
label
if
the
formulator,
user
group,
or
grower
has
complied
with
U.
S.
EPA
submission
requirements
regarding
support
of
such
use(
s)."

"
This
product
may
be
used
to
formulate
products
for
any
additional
use(
s)
not
listed
on
the
MP
label
if
the
formulator,
user
group,
or
grower
has
complied
with
U.
S.
EPA
submission
requirements
regarding
support
of
such
use(
s)."
Directions
for
Use
Packaging
statement
required
by
the
RED
for
wettable­
powder
formulations
"
All
wettable­
powder
formulations
must
be
packaged
in
water­
soluble
packaging."
Directions
for
Use
Description
Amended
Labeling
Language
Placement
on
Label
50
Environmental
Hazards
Statements
Required
by
the
RED
and
Agency
Label
Policies
"
Do
not
discharge
effluent
containing
this
product
into
lakes,
streams,
ponds,
estuaries,
oceans,
or
other
waters
unless
in
accordance
with
the
requirements
of
a
National
Pollution
Discharge
Elimination
System
(
NPDES)
permit
and
the
permitting
authority
has
been
notified
in
writing
prior
to
discharge.
Do
not
discharge
effluent
containing
this
product
to
sewer
systems
without
previously
notifying
the
local
sewage
treatment
plant
authority.
For
guidance
contact
your
State
Water
Board
or
Regional
Office
of
the
EPA."

"
Do
not
apply
this
product
within
15
feet
of
bodies
of
water
that
may
serve
as
sources
of
drinking
water."
Directions
for
Use
End
Use
Products
Front
Panel
Statement
for
Granular
and
Wettable
Powder
Products
"
For
sale
to
and
use
by
professional
applicators
only.
Not
for
sale
to
or
use
by
homeowners/
consumers."
Insert
in
a
prominent
position
associated
with
the
Brand
name
on
the
front
panel
of
the
pesticide
label
Description
Amended
Labeling
Language
Placement
on
Label
51
PPE
Requirements
Established
by
the
RED
for
wettable
powders
formulations
"
Personal
Protective
Equipment
(
PPE)"

"
Some
materials
that
are
chemical­
resistant
to
this
product
are"
(
registrant
inserts
correct
chemical­
resistant
material).
"
If
you
want
more
options,
follow
the
instructions
for
category"
[
registrant
inserts
A,
B,
C,
D,
E,
F,
G,
or
H]
"
on
an
EPA
chemical­
resistance
category
selection
chart."

"
Mixers,
loaders,
applicators,
and
other
handlers
must
wear:

­
Long­
sleeved
shirt
and
long
pants,

­
Shoes
plus
socks,
and
­
Chemical
resistant
gloves,
such
as
(
registrant
insert
correct
chemical­
resistant
materials),

In
addition,
mixers
and
loaders
must
wear
a
chemical­
resistant
apron.

See
engineering
controls
for
additional
requirements."
Immediately
following/
below
Precautionary
Statements:

Hazards
to
Humans
and
Domestic
Animals
PPE
Requirements
Established
by
the
RED
for
granular
formulations
"
Personal
Protective
Equipment
(
PPE)

Loaders,
applicators,
and
other
handlers
must
wear:

­
Long­
sleeved
shirt
and
long
pants,
and
­
Shoes
plus
socks."
Immediately
following/
below
Precautionary
Statements:

Hazards
to
Humans
and
Domestic
Animals
User
Safety
Requirements
for
Wettable
Powder
Formulations
and
Granular
Formulations
"
Follow
manufacturer's
instructions
for
cleaning/
maintaining
PPE.
If
no
such
instructions
for
washables
exist,

use
detergent
and
hot
water.
Keep
and
wash
PPE
separately
from
other
laundry."
Precautionary
Statements:

Hazards
to
Humans
and
Domestic
Animals
immediately
following
the
PPE
requirements
Description
Amended
Labeling
Language
Placement
on
Label
52
Engineering
Controls
for
Wettable
Powder
Formulations
(
Wettable
powders
products
must
be
contained
in
water
soluble
packaging
to
be
eligible
for
reregistration)
"
Water­
soluble
packets
when
used
correctly
qualify
as
a
closed
mixing/
loading
system
under
the
Worker
Protection
Standard
for
Agricultural
Pesticides
[
40
CFR
170.240(
d)(
4)].
Mixers
and
loaders
using
watersoluble
packets
must
:

­
wear
the
personal
protective
equipment
required
above
for
mixers/
loaders,
and
­
be
provided
and
have
immediately
available
for
use
in
an
emergency,
such
as
a
broken
package,
spill,
or
equipment
breakdown:
chemical­
resistant
footwear
and
a
NIOSH­
approved
dust
mist
filtering
respirator
with
MSHA/
NIOSH
approval
number
prefix
TC­
21C
or
a
NIOSH­
approved
respirator
with
any
N,
R,
P,
or
HE
filter."
Precautionary
Statements:

Hazards
to
Humans
and
Domestic
Animals
(
Immediately
following
PPE
and
User
Safety
Requirements.)

User
Safety
Recommendations
"
User
Safety
Recommendations
Users
should
wash
hands
before
eating,
drinking,
chewing
gum,
using
tobacco,
or
using
the
toilet.

Users
should
remove
clothing/
PPE
immediately
if
pesticide
gets
inside.
Then
wash
thoroughly
and
put
on
clean
clothing.

Users
should
remove
PPE
immediately
after
handling
this
product.
Wash
the
outside
of
gloves
before
removing.
As
soon
as
possible,
wash
thoroughly
and
change
into
clean
clothing."
Precautionary
Statements
under:

Hazards
to
Humans
and
Domestic
Animals
immediately
following
Engineering
Controls
(
Must
be
placed
in
a
box.)

Restricted­
Entry
Interval
for
WPS
uses
"
Do
not
enter
or
allow
worker
entry
into
treated
areas
during
the
restricted
entry
interval
(
REI)
of
12
hours."
Directions
for
Use,

Agricultural
Use
Requirements
Box
Description
Amended
Labeling
Language
Placement
on
Label
53
Early
Entry
Personal
Protective
Equipment
established
by
the
RED.
"
PPE
required
for
early
entry
to
treated
areas
that
is
permitted
under
the
Worker
Protection
Standard
and
that
involves
contact
with
anything
that
has
been
treated,
such
as
plants,
soil,
or
water,
is:

­
coveralls,

­
shoes
plus
socks,
and
­
chemical­
resistant
gloves
made
of
any
waterproof
material."

General
Application
Restrictions
"
Do
not
apply
this
product
in
a
way
that
will
contact
workers
or
other
persons,
either
directly
or
through
drift.

Only
protected
handlers
may
be
in
the
area
during
application."
Place
in
the
Directions
for
Use
directly
above
the
Agricultural
Use
Box.

Application
Restrictions
for
Granular
and
Wettable
Powder
Formulations
The
label
must
be
revised
to
specify
a
maximum
application
rate
of
xxx
{
registrant
to
provide
value}
pounds
of
product
per
acre
per
year
(
equivalent
to
6
pounds
ai/
A/
year),
except
in
areas
where
there
is
heavy
weed
infestation.
In
areas
of
heavy
weed
infestation,
the
maximum
application
rate
is
xxx
{
registrant
to
provide
value}
pounds
of
product
per
acre
per
year
(
equivalent
to
8
pounds
ai/
A/
year)
.

The
label
must
be
revised
to
specify
a
maximum
single
application
rate
of
xxx
{
registrant
to
provide
value}

pounds
of
product
per
acre
(
equivalent
to
4
pounds
ai/
A)

The
label
must
be
revised
to
read
"
Not
for
use
on
home
lawns."
Directions
For
Use
under
General
Precautions
and
Restrictions
Application
Restrictions
for
Granular
Formulations
"
The
label
must
be
revised
to
read
"
For
best
results,
water­
in
the
product
as
soon
as
practical
after
application."

1
PPE
that
is
established
on
the
basis
of
Acute
Toxicity
of
the
end­
use
product
must
be
compared
to
the
active
ingredient
PPE
in
this
document.
The
more
protective
PPE
must
be
placed
in
the
product
labeling.
For
guidance
on
which
PPE
is
considered
more
protective,
see
PR
Notice
93­
7.

2
If
the
product
contains
oil
or
bears
instructions
that
will
allow
application
with
an
oil­
containing
material,
the
"
N"
designation
must
be
dropped.

Instructions
in
the
Labeling
section
appearing
in
quotations
represent
the
exact
language
that
should
appear
on
the
label.

Instructions
in
the
Labeling
section
not
in
quotes
represents
actions
that
the
registrant
should
take
to
amend
their
labels
or
product
registrations.
54
D.
Existing
Stocks
Registrants
may
generally
distribute
and
sell
products
bearing
old
labels/
labeling
for
26
months
from
the
date
of
the
issuance
of
this
Reregistration
Eligibility
Decision
(
RED).
Persons
other
than
the
registrant
may
generally
distribute
or
sell
such
products
for
50
months
from
the
date
of
the
issuance
of
this
RED.
Refer
to
"
Existing
Stocks
of
Pesticide
Products;
Statement
of
Policy";
Federal
Register,
Volume
56,
No.
123,
June
26,
1991.
55
Appendix
A.
Table
of
Oxadiazon
Use
Patterns
Eligible
for
Reregistration
56
Appendix
A
OXADIAZON
(
CASE
2485)
USE
PATTERNS
ELIGIBLE
FOR
REREGISTRATION
Site
Application
Equipment
Formulation
Maximum
Single
Application
Rate
Max
No
of
Appl
per/
y
Restrictions
Turf:
golf
course,
ornamental
Groundboom
Application,

Handgun
Application,

Tractor
Drawn
Spreader,

Backpack
Sprayer,

Low
Pressure
Handwand,

Push
Type
Spreader,

Bellygrinder.
Granular
Water­
soluble
powder
4
lb
ai/
acre
3
Maximum
6
lbs
ai/
A/
yr
except
in
cases
of
heavy
weed
infestation
(
8
lb
ai/
A/
yr)

Do
not
apply
through
any
type
of
irrigation
system.

Do
not
contaminate
water
by
cleaning
of
equipment
or
disposal
of
equipment
wash
waters.

Do
not
contaminate
water,
food,
or
feed
by
storage
or
disposal.

Do
not
store
or
use
in
or
around
the
home
or
home
garden.

Do
not
graze
livestock
in
treated
areas.

Turf:
sod
farms
Chemigation
Application
Groundboom
Application
Granular
Water­
soluble
powder
4
lb
ai/
acre
3
Maximum
6
lbs
ai/
A/
yr
except
in
cases
of
heavy
weed
infestation
(
8
lb
ai/
A/
yr)

Do
not
apply
through
any
type
of
irrigation
system.

Do
not
contaminate
water
by
cleaning
of
equipment
or
disposal
of
equipment
wash
waters.

Do
not
contaminate
water,
food,
or
feed
by
storage
or
disposal.

Do
not
store
or
use
in
or
around
the
home
or
home
garden.

Do
not
graze
livestock
in
treated
Site
Application
Equipment
Formulation
Maximum
Single
Application
Rate
Max
No
of
Appl
per/
y
Restrictions
57
areas.
Nursery:
woody
ornamental
shrubs,
vines
and
trees
Groundboom
Application
Handgun
Applicators
Tractor
Drawn
Spreader
Backpack
Sprayer
Low
Pressure
Handwand
Push
Type
Spreader
Bellygrinder
Granular
Water­
soluble
powder
4
lb
ai/
acre
3
Maximum
6
lbs
ai/
A/
yr
except
in
cases
of
heavy
weed
infestation
(
8
lb
ai/
A/
yr)

Do
not
apply
through
any
type
of
irrigation
system.

Do
not
contaminate
water
by
cleaning
of
equipment
or
disposal
of
equipment
wash
waters.

Do
not
contaminate
water,
food,
or
feed
by
storage
or
disposal.

Do
not
store
or
use
in
or
around
the
home
or
home
garden.

Do
not
graze
livestock
in
treated
areas.

Roadsides,
rights­
of­
way
Rights­
of­
way
sprayer
Granular
Water­
soluble
powder
4
lb
ai/
acre
3
Maximum
6
lbs
ai/
A/
yr
except
in
cases
of
heavy
weed
infestation
(
8
lb
ai/
A/
yr)

Do
not
apply
through
any
type
of
irrigation
system.

Do
not
contaminate
water
by
cleaning
of
equipment
or
disposal
of
equipment
wash
waters.

Do
not
contaminate
water,
food,
or
feed
by
storage
or
disposal.

Do
not
store
or
use
in
or
around
the
home
or
home
garden.

Do
not
graze
livestock
in
treated
areas.
58
Appendix
B.
Table
of
Generic
Data
Requirements
and
Studies
Used
to
Make
the
Reregistration
Decision
59
60
APPENDIX
B
Data
Supporting
Guideline
Requirements
for
the
Reregistration
of
Oxadiazon
REQUIREMENT
USE
PATTERN
CITATION(
S)

PRODUCT
CHEMISTRY
New
Guideline
Number
Old
Guideline
Number
830.1550
61­
1
Product
Identity
and
Composition
All
40968001
830.1600
61­
2A
Start.
Mat.
&
Mnfg.
Process
All
40968001
830.1670
61­
2B
Formation
of
Impurities
All
40968001
830.1700
62­
1
Preliminary
Analysis
All
41863601
830.1750
62­
2
Certification
of
limits
All
41863601
830.1800
62­
3
Analytical
Method
All
41863601
830.6302
63­
2
Color
All
41842801
830.6303
63­
3
Physical
State
All
41842801
830.6304
63­
4
Odor
All
41842801
830.7050
None
UV/
Visible
Absorption
All
Data
gap
830.7200
63­
5
Melting
Point
All
41842801
830.7300
63­
7
Density
All
41565701
830.7840
830.7860
63­
8
Solubility
All
41474201
830.7950
63­
9
Vapor
Pressure
All
41230301
830.7550
63­
11
Octanol/
Water
Partition
Coefficient
All
41230302
830.6313
63­
13
Stability
All
41877601
ECOLOGICAL
EFFECTS
850.2100
71­
1
Avian
Acute
Oral
Toxicity
C
41610101
850.2200
71­
2
Avian
Dietary
Toxicity
C
41610102
41610103
850.2300
71­
4
Avian
Reproduction
C
41993201
41993202
850.1075
72­
1A
Fish
Toxicity
C
42330401
42350601
850.1010
72­
2
Freshwater
Invertebrate
Toxicity
C
42331801
850.1075
72­
3(
a)
Estuarine/
Marine
Toxicity
­
Fish
C
42615801
850.1025
72­
3(
b)
Estuarine/
Marine
Toxicity
­
Mollusk
C
42570301
850.1035
850.1045
72­
3(
c)
Estuarine/
Marine
Toxicity
­
Shrimp
C
42615802
850.1400
72­
4(
a)
Estuarine
Fish­
Early
Life
Stage
C
Data
gap
Data
Supporting
Guideline
Requirements
for
the
Reregistration
of
Oxadiazon
REQUIREMENT
USE
PATTERN
CITATION(
S)

61
850.1300
850.1350
72­
4(
b)
Estuarine/
Marine
Invertebrate
Life
Cycle
C
Data
gap
850.4100
122­
1(
a)
Seed
Germ./
Seedling
Emergence
Tier
I
C
Data
gap
850.4150
122­
1(
b)
Vegetative
Vigor
Tier
I
C
Data
gap
850.4400
122­
2
Aquatic
Plant
Growth
C
41610105
41610106
41610107
41610108
42659001
850.4225
123­
1(
a)
Seed
Germ./
Seedling
Emergence
Tier
II
C
Data
gap
850.4250
123­
1(
b)
Vegetative
Vigor
Tier
II
C
Data
gap
850.4400
123­
2
Aquatic
Plant
Growth
C
41610105­
41610108
850.3020
141­
1
Honey
Bee
Acute
C
42468301
70­
1
Aquatic
Phototoxicity
Studies
(
Fathead
minnow)
C
Data
gap
70­
1
Acute
and
Chronic
Sediment
Toxicity
Testing
C
Data
gap
70­
1
Water
Monitoring
Study
C
Data
gap
TOXICOLOGY
870.1100
81­
1
Acute
Oral
Toxicity­
Rat
C
41866501
870.1200
81­
2
Acute
Dermal
Toxicity­
Rabbit
C
41866502
870.1300
81­
3
Acute
Inhalation
Toxicity­
Rat
C
41866503
870.2400
81­
4
Primary
Eye
Irritation­
Rabbit
C
41866504
870.2500
81­
5
Primary
Skin
Irritation
C
41866505
870.2600
81­
6
Dermal
Sensitization
C
41230401
870.3100
82­
1A
90­
Day
Feeding
­
Rodent
C
00111804
870.3150
82­
1B
90­
Day
Feeding
­
Dog
C
00111805
870.3200
82­
2
21­
Day
Dermal
­
Rabbit
C
41863602
870.3465
82­
4
28­
day
inhalation
toxicity
C
Data
gap
870.3700a
83­
3A
Prenatal
development
(
rat)
C
40470202
870.3700b
83­
3B
Prenatal
development
(
rabbit)
C
40470201
870.3800
83­
4
Reproduction
and
fertility
effects
(
rat)
C
41239801
870.4100a
83­
1A
Chronic
Feeding
Toxicity
­
Rodent
C
see
870.4300
870.4100b
83­
1B
Chronic
Feeding
Toxicity
­
Dog
C
41326401
870.4200
83­
2B
Oncogenicity
­
Mouse
C
00115733
40993301
870.4300
83­
5
Combined
Chronic
Toxicity/
Carcinogenicity­
Rat
C
00149003
00157780
40993401
Data
Supporting
Guideline
Requirements
for
the
Reregistration
of
Oxadiazon
REQUIREMENT
USE
PATTERN
CITATION(
S)

62
870.5100­

870.5500
84­
2A­
84­
2B
Gene
mutation
studies
C
00069893
41871701
00115726
00115729
870.5375
Cytogenetics
In
vitro
mammalian
cell
chromosomal
aberration
assay
C
00115728
00115730
870.5550
84­
4
Other
Effects
C
00115723
00115727
00115703
870.7485
85­
1
General
Metabolism
C
42324701
42663601
870.7600
Dermal
penetration­
Rat
C
44588101
Special
Study
42310001
OCCUPATIONAL/
RESIDENTIAL
EXPOSURE
875.2100
132­
1A
Transferable
Residue
Dissipation:
Lawn
and
Turf
C
43517801
ENVIRONMENTAL
FATE
835.2120
161­
1
Hydrolysis
C
41863603
835.2240
161­
2
Photodegradation
­
Water
C
41897201
835.2410
161­
3
Photodegradation
­
Soil
C
41898201
835.4100
162­
1
Aerobic
Soil
Metabolism
C
42772801
835.4400
162­
3
Anaerobic
Aquatic
Metabolism
C
42773802
835.4300
162­
4
Aerobic
Aquatic
Metabolism
C
Data
gap
835.1230
835.1240
163­
1
Leaching/
Adsorption/
Desorption
C
41898202
41889601
835.6100
164­
1
Terrestrial
Field
Dissipation
C
41767401
None
165­
4
Bioaccumulation
in
Fish
C
42226701
63
Appendix
C.
Technical
Support
Documents
64
Appendix
C.
TECHNICAL
SUPPORT
DOCUMENTS
Additional
documentation
in
support
of
this
RED
is
maintained
in
the
OPP
docket,
located
in
Room
119,
Crystal
Mall
#
2,
1921
Jefferson
Davis
Highway,
Arlington,
VA.
It
is
open
Monday
through
Friday,
excluding
legal
holidays,
from
8:
30
am
to
4
pm.

The
docket
initially
contained
preliminary
risk
assessments
and
related
documents
as
of
February
19,
2003.
Sixty
days
later
the
first
public
comment
period
closed.

All
documents,
in
hard
copy
form,
may
be
viewed
in
the
OPP
docket
room
or
downloaded
or
viewed
via
the
Internet
at
the
following
site:

http://
www.
epa.
gov/
edocket/

These
documents
include:

HED
Documents:

3.
OXADIAZON:
Response
to
the
30­
day
Error
Only
Comments
on
the
HED
Chapter
of
the
Reregistration
Eligibility
Decision
Document
(
RED).
PC
Code:
109001,
Case
#
819425,
Submission
No.
S610158,
DP
Barcode:
D280876
[
49
pages]

4.
Revised
Occupational
and
Residential
Exposure
Assessment
and
Recommendations
for
the
Reregistration
Eligibility
Decision
Document
for
Oxadiazon.
DP
Barcode:
D276360
[
62
pages]

5.
Oxadiazon.
Reregistration
Case
No.
2680.
Toxicology
Chapter
for
the
Reregistration
Eligibility
Decision
(
RED)
Document
for
Oxadiazon.
DP
Barcode:
D266361
[
45
pages]

6.
Oxadiazon­
Report
of
the
Hazard
Identification
Assessment
Review
Committee.
(
HED
Doc.
No.
014469
)
[
30
pages]

7.
Cancer
Assessment
Document
Evaluation
of
the
Carcinogenic
Potential
of
Oxadiazon
(
Third
Review)
(
HED
Doc.
No.
014555)
[
28
pages]

8.
Oxadiazon:
Assessment
of
Mode
of
Action
on
Liver
Carcinogenicity.
DP
Barcode:
D266361
[
15
pages]

9.
Revised
Oxadiazon
Quantitative
Risk
Assessment
(
Q1*)
Based
On
ICR­
JCL
Mouse
and
SPF
Wistar
Rat
Dietary
Studies
With
3/
4'
s
Interspecies
Scaling
Factor
(
HED
Doc.
No.
014465)
[
3
pages]

10.
Oxadiazon.
(
List
B,
Case
No.
2485)
The
Outcome
of
the
HED
Metabolism
Assessment
Review
Committee
Meeting
Held
on
1/
30/
01.
DP
Barcode
272425.
Chemical
109001.
[
4
pages]

11.
Oxadiazon.
List
B
Reregistration
Case
2485.
PC
Code
109001.
Product
Chemistry
and
Residue
Chemistry
Chapter
for
the
Reregistration
Eligibility
Decision
[
RED]
Document.
DP
Barcode
D273740.
[
3
pages]
65
12.
Oxadiazon.
List
B
Reregistration
Case
2485.
PC
Code
109001.
Product
Chemistry
and
Residue
Chemistry
Chapter
for
the
Reregistration
Eligibility
Decision
[
RED]
Document.
DP
Barcode
D273740.
[
12
pages]

EFED
Documents:

1.
EFED
Risk
Assessment
for
the
Reregistration
Eligibility
Decision
of
Oxadiazon.
DP
Barcode:
D280320
[
83
pages]

2.
Tier
I
Estimated
Environmental
Concentration
of
Oxadiazon.
DP
Barcode:
D273599
[
4
pages]

3.
Tier
II
Estimated
Drinking
Water
Concentrations
(
EDWCs)
for
Human
Health
Risk
for
oxadiazon
on
Florida
Golf
Course
(
PC
Code
1090001,
DP
Code:
D281176)
[
7
pages]
66
Appendix
D.
Citations
Considered
to
be
Part
of
the
Database
Supporting
the
Reregistration
Decision
(
Bibliography)
67
Appendix
D.
CITATIONS
CONSIDERED
TO
BE
PART
OF
THE
DATA
BASE
SUPPORTING
THE
INTERIM
REREGISTRATION
DECISION
(
BIBLIOGRAPHY)

GUIDE
TO
APPENDIX
D
1.
CONTENTS
OF
BIBLIOGRAPHY.
This
bibliography
contains
citations
of
all
studies
considered
relevant
by
EPA
in
arriving
at
the
positions
and
conclusions
stated
elsewhere
in
the
Reregistration
Eligibility
Document.
Primary
sources
for
studies
in
this
bibliography
have
been
the
body
of
data
submitted
to
EPA
and
its
predecessor
agencies
in
support
of
past
regulatory
decisions.
Selections
from
other
sources
including
the
published
literature,
in
those
instances
where
they
have
been
considered,
are
included.

2.
UNITS
OF
ENTRY.
The
unit
of
entry
in
this
bibliography
is
called
a
"
study".
In
the
case
of
published
materials,
this
corresponds
closely
to
an
article.
In
the
case
of
unpublished
materials
submitted
to
the
Agency,
the
Agency
has
sought
to
identify
documents
at
a
level
parallel
to
the
published
article
from
within
the
typically
larger
volumes
in
which
they
were
submitted.
The
resulting
"
studies"
generally
have
a
distinct
title
(
or
at
least
a
single
subject),
can
stand
alone
for
purposes
of
review
and
can
be
described
with
a
conventional
bibliographic
citation.
The
Agency
has
also
attempted
to
unite
basic
documents
and
commentaries
upon
them,
treating
them
as
a
single
study.

3.
IDENTIFICATION
OF
ENTRIES.
The
entries
in
this
bibliography
are
sorted
numerically
by
Master
Record
Identifier,
or
"
MRID"
number.
This
number
is
unique
to
the
citation,
and
should
be
used
whenever
a
specific
reference
is
required.
It
is
not
related
to
the
six­
digit
"
Accession
Number"
which
has
been
used
to
identify
volumes
of
submitted
studies
(
see
paragraph
4(
d)(
4)
below
for
further
explanation).
In
a
few
cases,
entries
added
to
the
bibliography
late
in
the
review
may
be
preceded
by
a
nine
character
temporary
identifier.
These
entries
are
listed
after
all
MRID
entries.
This
temporary
identifying
number
is
also
to
be
used
whenever
specific
reference
is
needed.

4.
FORM
OF
ENTRY.
In
addition
to
the
Master
Record
Identifier
(
MRID),
each
entry
consists
of
a
citation
containing
standard
elements
followed,
in
the
case
of
material
submitted
to
EPA,
by
a
description
of
the
earliest
known
submission.
Bibliographic
conventions
used
reflect
the
standard
of
the
American
National
Standards
Institute
(
ANSI),
expanded
to
provide
for
certain
special
needs.

a
Author.
Whenever
the
author
could
confidently
be
identified,
the
Agency
has
chosen
to
show
a
personal
author.
When
no
individual
was
identified,
the
Agency
has
shown
an
identifiable
laboratory
or
testing
facility
as
the
author.
When
no
author
or
laboratory
could
be
identified,
the
Agency
has
shown
the
first
submitter
as
the
author.

b.
Document
date.
The
date
of
the
study
is
taken
directly
from
the
document.
When
the
date
is
followed
by
a
question
mark,
the
bibliographer
has
deduced
the
date
from
the
evidence
contained
in
the
document.
When
the
date
appears
as
(
1999),
the
Agency
was
unable
to
determine
or
estimate
the
date
of
the
document.
68
c.
Title.
In
some
cases,
it
has
been
necessary
for
the
Agency
bibliographers
to
create
or
enhance
a
document
title.
Any
such
editorial
insertions
are
contained
between
square
brackets.

d.
Trailing
parentheses.
For
studies
submitted
to
the
Agency
in
the
past,
the
trailing
parentheses
include
(
in
addition
to
any
self­
explanatory
text)
the
following
elements
describing
the
earliest
known
submission:

(
1)
Submission
date.
The
date
of
the
earliest
known
submission
appears
immediately
following
the
word
"
received."

(
2)
Administrative
number.
The
next
element
immediately
following
the
word
"
under"
is
the
registration
number,
experimental
use
permit
number,
petition
number,
or
other
administrative
number
associated
with
the
earliest
known
submission.

(
3)
Submitter.
The
third
element
is
the
submitter.
When
authorship
is
defaulted
to
the
submitter,
this
element
is
omitted.

(
4)
Volume
Identification
(
Accession
Numbers).
The
final
element
in
the
trailing
parentheses
identifies
the
EPA
accession
number
of
the
volume
in
which
the
original
submission
of
the
study
appears.
The
six­
digit
accession
number
follows
the
symbol
"
CDL,"
which
stands
for
"
Company
Data
Library."
This
accession
number
is
in
turn
followed
by
an
alphabetic
suffix
which
shows
the
relative
position
of
the
study
within
the
volume.
69
PRODUCT
CHEMISTRY
40968001
Brocahard,
M.
(
1988)
Oxadiazon
Manufacturing
Process
and
Discussion
of
Formation
of
Impurities.
Unpublished
compilation
prepared
by
Rhone­
Poulen
Sante.
54
p.

41230301
Citation:
Hoffman,
M.
(
1989)
Vapor
Pressure
Determination
of
Oxadiazon:
Final
Report:
HLA
6001­
372.
Unpublished
study
prepared
by
Hazleton
Laboratories
Americas,
Inc.
71
p.

41230302
Seymour,
R.,
Hall,
L.
(
1988)
Octanol/
Water
Partition
Coefficient
Determination
for
Oxadiazon.
Unpublished
study
prepared
by
Rhone­
Poulenc
Ag
Co.
12
p.

41474201
Pruitt,
P.
(
1987)
Solubility
of
Oxadiazon
(
R.
P.­
17623)
in
Selected
Solvents:
Lab
Project
Number:
40207.
Unpublished
study
prepared
by
Rhone­
Poulenc
Ag
Co.
8
p.

41565701
Chabassol,
Y.
(
1990)
Oxadiazon­
Specific
Gravity
and
Density
at
20
(
degree)
C:
Lab
Project
Number:
89­
15.
Unpublished
study
prepared
by
Rhone­
Poulenc
Secteur
Agro.
16
p.

41842801
Chabassol,
Y.
(
1991)
Oxadiazon
Technical
Grade
Physical
Properties:
Lab
Project
Number:
90­
26.
Unpublished
study
prepared
by
Rhone­
Poulenc
Secteur
Agro.
40
p.

41863601
Chabossol,
Y.;
Chabert,
M.;
Hunt,
G.
et
al.
(
1991)
Oxadiazon
Technical
Grade:
Analysis
and
Certification
of
Product
Ingredients.
Lab
Project
Number:
90­
12:
9115221.
Unpublished
study
prepared
by
Rhone­
Poulenc,
Secteur
Agro.
462
p.

41877601
Sanders,
J.
(
1991)
Oxadiazon,
Technical:
Determination
of
Stability:
Lab
Project
Number:
4053­
91­
0061­
AS.
Unpublished
study
prepared
by
Ricerca,
Inc.
102
p.

ECOLOGICAL
EFFECTS
41610101
Pedersen,
C.
(
1990)
Oxadiazon
Technical:
21­
Day
Acute
Oral
LD50
Study
in
bobwhite
Quail:
Lab
Project
Number:
BLAL/
NO/
89
QD
139.
Unpublished
study
prepared
by
Bio­
Life
Associates,
Ltd.
35
p.

41610102
Pedersen,
C.
(
1990)
Oxadiazon
Technical:
8­
Day
Acute
Dietary
LC50
Study
in
bobwhite
Quail:
Lab
Project
Number:
BLAL/
NO/
89
QC
141.
Unpublished
study
prepared
by
Bio­
Life
Associates,
Ltd.
82
p.
70
41610103
Pedersen,
C.
(
1990)
Oxadiazon
Technical:
8­
Day
Acute
Dietary
LC50
Study
in
Mallard
Ducklings:
Lab
Project
Number:
BLAL/
NO/
89
DC
137.
Unpublished
study
prepared
by
Bio­
Life
Associates,
Ltd.
80
p.

41610105
Giddings,
J.
(
1990)
Oxadiazon
Technical­
Toxicity
to
the
Marine
Diatom
Skeletonema
costatum:
Lab
Project
Number:
90­
7­
3384:
10566­
1089­
6137­
450.
Unpublished
study
prepared
by
Springborn
Laboratories,
Inc.
55
p.

41610106
Giddings,
J.
(
1990)
Oxadiazinon
Technical­
Toxicity
to
the
Freshwater
Diatom
Navicula
pelliculosa:
Lab
Project
Number:
90­
8­
3423;
10566­
1089­
6137­
440.
Unpublished
study
prepared
by
Springborn
Laboratories,
Inc.
52
p.

41610107
Giddings,
J.
(
1990)
Oxadiazon
Technical­
Toxicity
to
the
Duckweed
Lemma
gibba
G3:
Final
Report:
Lab
Project
Number:
90­
7­
3389;
10566.1089.6137.410.
Unpublished
study
prepared
by
Springborn
Laboratories,
Inc.
48
p.

41610108
Giddings,
J.
(
1990)
Oxadiazon
Technical­
Toxicity
to
the
Freshwater
Green
Alga
Selenastrum
capricornutum:
Amended
Report:
Lab
Project
Number:
90­
8­
3422;
10566.1089.6137.437.
Unpublished
study
prepared
by
Springborn
Laboratories,
Inc.
52
p.

41784301
Blakemore,
G.;
Burgess,
D.
(
1991)
Chronic
Toxicity
of
Oxadiazon
Technical
to
Daphnia
magna
under
Flow­
thru
Conditions:
Final
Report:
Lab
Project
Number:
38369.
Unpublished
study
prepared
by
Analytical
Bio­
Chemistry
Labs.,
Inc.
349
p.

41993201
Fletcher,
D.;
Pedersen,
C.
(
1991)
Oxadiazon
Technical:
Toxicity
and
Reproduction
Study
in
Mallard
Ducks:
Lab
Project
Number:
89
DR
35.
Unpublished
study
prepared
by
Bio­
Life
Associates,
Ltd.
138
p.

41993202
Fletcher,
D.;
Pedersen,
C.
(
1991)
Oxadiazon
Technical:
Toxicity
and
Reproduction
Study
in
bobwhite
Quail:
Lab
Project
Number:
89
QR
39.
Unpublished
study
prepared
by
Bio­
Life
Associates,
Ltd.
145
p.

42330401
Sword,
M.;
Northup,
R.
(
1992)
Acute
Flow­
Through
Toxicity
of
Oxadiazon
to
Rainbow
Trout
(
Oncorhynchus
mykiss):
Lab
Project
Number:
39729.
Unpublished
study
prepared
by
ABC
Laboratories,
Inc.
211
p.

42331801
Blasberg,
J.;
Bowman,
J.
(
1992)
Acute
Toxicity
of
Oxadiazon
to
Daphnia
magna
under
Flow­
through
Conditions:
Amended
Final
Report:
Lab
Project
Number:
39730.
Unpublished
study
prepared
by
ABC
Labs,
Inc.
254
p.
71
42350601
Sword,
M.;
Northup,
R.
(
1992)
Acute
Flow­
through
Toxicity
of
Oxadiazon
to
Bluegill
(
Lepomis
macrochirus):
Final
Report:
Lab
Project
Number:
39728.
Unpublished
study
prepared
by
ABC
Labs.,
Inc.
194
p.

42468301
Beevers,
M.
(
1992)
Acute
Contact
Toxicity
of
Oxadiazon
Technical
to
Honey
Bees
(
Apis
mellifera
L.):
Lab
Project
Number:
CAR
160­
92.
Unpublished
study
prepared
by
California
Agricultural
Research,
Inc.
14
p.

42570301
Dionne,
E.
(
1992)
Oxadiazon
Technical­­
Acute
Toxicity
to
Eastern
Oyster
(
Crassostrea
virginica)
under
Flow­
through
Conditions:
Final
Report:
Lab
Project
Number:
92­
7­
4329:
10566.
0392.6238.504.
Unpublished
study
prepared
by
Springborn
Labs,
Inc.
63
p.

42615801
Machado,
M.
(
1992)
Oxadiazon
Technical­­
Acute
Toxicity
to
Sheepshead
Minnow
(
Cyprinodon
variegatus)
under
Flow­
through
Conditions:
Final
Report:
Lab
Project
Number:
92­
8­
4383
10566.0392.6237.505.
Unpublished
study
prepared
by
Springborn
Labs,
Inc.
66
p.

42615802
Machado,
M.
(
1992)
Oxadiazon
Technical­­
Acute
Toxicity
to
Mysid
Shrimp
(
Mysidopsis
bahia)
under
Flow­
through
Conditions:
Final
Report:
Lab
Project
Number:
92­
7­
4348:
10566.0392.6236.515.
Unpublished
study
prepared
by
Springborn
Labs,
Inc.
65
p.

42659001
Mihaich,
E.
(
1993)
Response
to
EPA
Review
of
Oxadiazon
Anabaena
flos­
aquae
Study
(
MRID
41610104)
and
Selenastrum
caprocornutum
(
sic)
Study
(
MRID
41610108):
Lab
Project
No.
NS/
EMM­
93­
03.
Unpublished
study
prepared
by
Rhone­
Poulenc
Ag
Co.
and
Springborn
Labs.,
Inc.
10
p.

TOXICOLOGY
00069893
Shirasu,
Y.,
Moriya,
M.
and
Kato,
K.
(
1976)
Microbial
Mutagenic
Study
on
Oxadiazon.
Institute
of
Environmental
Toxicology,
Nissan
Chemical
Industries,
Ltd.,
Japan.
No
study/
report
no.
provided.
Report
dated
June
4,
1976.
Unpublished
study.

00111804
Weatherholtz,
W.
and
Voelker,
R.
(
1970)
13­
week
Dietary
Administration­­
Rats:
RP
17623.
TRW,
Inc.,
Vienna,
VA.
Study
No.
656­
114.
May
28,
1970.
Unpublished
study.

00111805
Weatherholtz,
W.
and
Voelker,
R.
(
1970)
13­
week
Oral
Administration­­
Dogs:
RP
17623.
TRW,
Inc.,
Vienna,
VA.
Project
No.
656­
115.
May
22,
1970.
Unpublished
study.
72
00115703
Hossack,
D.
J.
N.
and
Daniel,
M.
R.
(
1982)
Oxadiazon
Lot
CA
76
204
and
Recrystallized
Oxadiazon
17
623
RP
Cell
Transformation
Test
for
Carcinogenicity.
Huntingdon
Research
Centre,
England.
Laboratory
report
number
RNP
152A/
79368,
July
29,
1982.
Unpublished
study.

00115723
Myhr,
B.
C.
and
McKeon,
M.
(
1982)
Evaluation
of
Oxadiazon
Recristallise
in
the
Primary
Rat
Hepatocyte
Unscheduled
DNA
Synthesis
Assay.
Litton
Bionetics,
Inc.,
Kensington,
MD.
LBI
Project
No.
20991.
June,
1982.
Unpublished
study.

00115726
Cifone,
M.
A
and
Balinas,
V.
(
1982)
Mutagenicity
Evaluation
of
Oxadiazon
in
the
Mouse
Lymphoma
Forward
Mutation
Assay.
Litton
Bionetics,
Inc.,
Kensington,
MD.
LBI
Project
No.
20999.
Unpublished
study.

00115727
Myhr,
B.;
McKeon,
M.
(
1982)
Evaluation
of
Oxadiazon
(
Lot
MAG
405)
in
the
Primary
Rat
Hepatocyte
Unscheduled
DNA
Synthesis
Assay.
Litton
Bionetics,
Inc.,
Kensington,
MD.
LBI
Project
No.
21001.
June,
1980.
Unpublished
study.

00115728
Galloway,
S.
and
Lebowitz,
H.
(
1982)
Mutagenicity
Evaluation
of
Oxadiazon
Recristallise,
Lot
BOS
2
385
in
an
in
vitro
Cytogenetic
Assay
Measuring
Chromosome
Aberration
Frequencies
in
Chinese
Hamster
Ovary
(
CHO)
Cells.
Litton
Bionetics,
Inc.,
Kensington,
MD.
LBI
Project
No.
21000.
July,
1982.
Unpublished
study.

00115729
Cifone,
M.
and
Balinas,
V.
(
1982)
Mutagenicity
Evaluation
of
Oxadiazon
Recristallise
in
the
Mouse
Lymphoma
Forward
Mutation
Assay.
Litton
Bionetics,
Inc.,
Kensington,
MD.
LBI
Project
No.
20999.
April,
1982.
Unpublished
study.

00115730
Galloway,
S.
and
Lebowitz,
H.
(
1982)
Mutagenicity
Evaluation
of
Oxadiazon,
Lot
MAG
405
in
an
in
vitro
Cytogenetic
Assay
Measuring
Chromosome
Aberration
Frequencies
in
Chinese
Hamster
Ovary
(
CHO)
Cells.
Litton
Bionetics,
Inc.,
Kensington,
MD.
LBI
Project
No.
21000.
July,
1982.
Unpublished
study.

00115733
Oxadiazon:
Oncogenicity
in
Dietary
Administration
to
Mice
for
a
Period
of
105
Weeks:
Project
No.
82/
RH000H/
245.
Prepared
by
Life
Science
Research.
10
p.

00149003
Kudo,
S.,
Takeuchi,
T.,
Hayashi,
K.
et
al.
(
1981)
Twenty­
four
Month
Chronic
Toxicity
Study
of
Oxiadiazon
in
Rats.
Nippon
Institute
for
Biological
Science
73
and
Institute
of
Environmental
Toxicology.
No
study/
report
no.
July,
1981.
Unpublished
study.

00157780
Nippon
Institute
for
Biological
Science
(
1986)
Twenty­
four
Month
Chronic
Toxicity
Study
of
Oxadiazon
in
Rats:
Revised
Data
Tables
per
EPA
Request.
Unpublished
data.

40470201
Tesh,
J.;
Ross,
F.;
Bailey,
G.;
et
al.
(
1987)
Oxadiazon:
Teratology
Study
in
the
Rabbit:
Laboratory
Project
ID
87/
RHA095/
534.
Unpublished
study
performed
by
Life
Science
Research,
England.
92
p.

40470202
Tesh,
J.;
McAnulty,
P.;
Wightman,
B;
et
al.
(
1987)
Oxadiazon:
Teratology
Study
in
the
Rat:
Laboratory
Project
ID
87/
RHA093/
356
.
Unpublished
study
performed
by
Life
Science
Research,
England.
145
p.

40993301
Shirasu,
Y.
(
1987)
Oxadiazon­­
23
Month
Oral
Chronic
Toxicity
and
Oncogenicity
Study
in
Mice.
Institute
of
Environmental
Toxicology,
Tokyo,
Japan.
Study
No.
not
listed.
February,
1987.
Unpublished
study.

40993401
Y.
Shirasu
(
1987).
Oxadiazon
­
24
Month
Chronic
Toxicity
and
Oncogenicity
Study
in
Rats.
Institute
of
Environmental
Toxicology,
Tokyo,
Japan;
Study
No.
not
listed.
February
1987.
Unpublished
study.

40993401
Y.
Shirasu
(
1987).
Oxadiazon
­
24
Month
Chronic
Toxicity
and
Oncogenicity
Study
in
Rats.
Institute
of
Environmental
Toxicology,
Tokyo,
Japan;
Study
No.
not
listed.
February
1987.
Unpublished
study.

41230401
Siglin,
J.
(
1988)
Delayed
contact
hypersensitivity
study
in
guinea
pigs
with
oxadiazon
(
EPA).
Springborn
Life
Sciences,
Inc.,
Spencerville,
OH.
Laboratory
Study
No.
3147.26.
December
20,
1988.
Unpublished
study.

41239801
Tesh,
J.;
McAnulty,
P.;
Higgins,
C.
(
1988)
Oxadiazon:
Effects
of
Dietary
Administartion
Upon
Reproductive
Performance
of
Rats
Treated
Continuously
Throughout
Two
Successive
Generations:
Pro­
ject
ID
88/
RHA097/
366.
863
p.

41326401
Chapman,
E.
(
1989)
Oxadiazon:
Toxicity
Study
by
Oral
(
Capsule)
Administration
to
Beagle
Dogs
for
52
Weeks:
Lab
Project
Number:
88/
0763.
Unpublished
study
prepared
by
Life
Science
Research,
Ltd.
560
p.
74
41863602
Siglin,
J.
C.
(
1991)
21­
Day
Dermal
Toxicity
Study
in
Rabbits
with
Oxadiazon
Technical.
Springborn
Labs,
Inc.,
Spencerville,
OH.
Lab
Project
Number:
3147.86.
March
20,
1991.
Unpublished
study.

41866501
Rush,
R.
(
1990)
Acute
Oral
Toxicity
Study
in
Rats
with
Oxadiazon:
Final
Report:
Lab
Project
Number:
3147.84.
Unpublished
study
prepared
by
Springborn
Laboratories,
Inc.
26
p.

41866502
Rush,
R.
(
1990)
Acute
Dermal
Toxicity
Study
in
Rabbits
with
Oxadia­
zon:
Final
Report:
Lab
Project
Number:
3147.85.
Unpublished
Study
prepared
by
Springborn
Laboratories,
Inc.
24
p.

41866503
Michlewicz,
K.
(
1988)
Acute
Inhalation
Toxicity
Study
of
Oxadiazon
in
Rats­
Limit
Test:
Lab
Project
Number:
3147.24.
Unpublished
Study
prepared
by
Springborn
Laboratories,
Inc.
32
p.

41866504
Rush,
R.
(
1991)
Primary
Eye
Irritation
Study
in
Rabbits
with
Oxadiazon:
Final
Report:
Lab
Project
Number:
3147.110.
Unpublished
Study
prepared
by
Springborn
Laboratories,
Inc.
30
p.

41866505
Rush,
R.
(
1991)
Primary
Skin
Irritation
Study
in
Rabbits
with
Oxadiazon:
Final
Report:
Lab
Project
Number:
3147.111.
Unpublished
Study
prepared
by
Springborn
Laboratories,
Inc.
22
p.

41871701
L.
F.
Stankowski,
Jr,
(
1991).
Ames
Salmonella
Plate
Incorporation
Assay
on
Oxadiazon.
Pharmalon
Research
International
Inc.,
Waverly,
PA.
Study
No.
PH
301­
RP­
001­
91.
April
30,
1991.
Unpublished
study.

42324701
Powles,
P.
(
1992)
(
14C)­
Oxadiazon:
Absorption,
Distribution,
Metabolism,
and
Excretion
in
the
Rat:
[
Final
Report].
Hazleton
UK,
England.
Study
No.
7120­
68/
118.
May
11,
1992.
Unpublished
study.

42663601
Powles,
P.
(
1993):
(
14C)­
Oxadiazon:
Absorption,
Distribution
Metabolism
and
Excretion
in
the
Rat.
[
Amendment
to
Final
Report
MRID
No.
42324701]
Hazleton
UK,
England.
Study
No.
7120­
68/
118.
February
9,
1993.
Unpublished
study.

44588101
Cheng,
T.
(
1996)
Dermal
Absorption
of
14C­
Oxadiazon
in
Male
Rats
(
Preliminary
and
Definitive
Phases)
Corning
Hazleton,
Vienna,
VA.
Lab
Project
Number:
CHW
6224­
224.
75
OCCUPATIONAL/
RESIDENTIAL
EXPOSURE
43517801
Rosenheck,
L.;
Sanchez,
S.
(
1995)
Evaluation
of
Turf
Re­
entry
Exposure
to
a
Broadcast
Application
of
Ronstar
50WP:
Lab
Project
Number:
93293.
Unpublished
study
prepared
by
Pan­
Agricultural
Labs,
Inc.
300
p.

ENVIRONMENTAL
FATE
41767401
Norris,
F.
A.
1991.
A
terrestrial
field
soil
dissipation
study
with
oxadiazon.
Study
No.
EC/
P­
89­
0014.
File
No.
40642.
Unpublished
study
performed
and
submitted
by
Rhône­
Poulenc
Ag
Company,
Research
Triangle
Park,
NC
41863603
Corgier,
M.
M.
C.,
and
Robin,
J.
M.
1991.
14C­
Oxadiazon
Hydrolysis
at
25

C.
Unpublished
study
performed
by
Rhône­
Poulenc,
Lyon,
France,
and
submitted
by
Rhône­
Poulenc,
Research
Triangle
Park,
NC
41897201
Corgier,
M.
M.
C.,
and
A.
P.
Plewa.
1991.
14C­
oxadiazon
photodegradation
in
aqueous
solution.
Study
No.
90­
29.
Filing
Reference
AG/
CRLD/
AN/
9115609.
Unpublished
study
performed
by
Rhône­
Poulenc
Secteur
Agro,
Lyon,
France,
and
submitted
by
Rhône­
Poulenc
Ag
Company,
Research
Triangle
Park,
NC
41898201
Das,
Y.
T.
1991.
Photodegradation
of
[
Phenyl(
U)­
14C]
Oxadiazon
on
Soil
under
Artificial
Sunlight.
Unpublished
study
performed
by
Innovative
Scientific
Services,
Inc.
Piscataway,
N.
J.,
and
sponsored
and
submitted
by
Rhône­
Poulenc
Ag
Company,
Research
Triangle
Park,
NC
41898202
Dykes,
J.
1991.
Soil
Adsorption/
Desorption
with
14C­
Oxadiazon.
An
unpublished
study
performed
by
Analytical
Bio­
Chemistry
Laboratories,
Inc.,
Columbia,
MO,
nad
submitted
by
Rhône
Poulenc
Ag
Company,
Research
Triangle
Park,
NC
42226701
Armstrong,
K.,
B.
D.
Cameron,
S.
A.
Chapleo,
B.
E.
Hall,
and
A.
Haswell.
1991.
Oxadiazon:
Bioaccumulation
test
in
bluegill
sunfish.
IRI
Project
No.
381195;
Report
No.
8385.
Unpublished
study
performed
by
Inversk
Research
International,
Tranent,
Scotland,
and
submitted
by
Rhône­
Poulenc
Ag
Company,
Research
Triangle
Park,
NC
Manley,
J.
D.,
I.
A.
J.
Hardy,
and
E.
A.
Savage.
1992.
Herbicides:
Oxadiazon
spectroscopic
investigation
of
metabolites
from
a
[
14C]­
oxadiazon
bioaccumulation
test
in
bluegill
sunfish.
IRI
Project
No.
381195.
Unpublished
study
performed
by
Rhône­
Poulenc
Agriculture
Limited,
Ongar,
United
Kingdom,
and
submitted
by
Rhône­
Poulenc
Ag
Company,
Research
Triangle
Park,
NC
(
No
Study
ID)

42772801
Waring,
A.
R.
1993a.
[
14C]
Oxadiazon:
Aerobic
soil
metabolism.
HUK
Study
No.
68/
111;
Report
No.
7218.
Unpublished
study
performed
by
Hazleton
UK,
Harrogate,
North
Yorkshire,
England,
and
submitted
by
Rhône­
Poulenc
Agriculture
Company,
Research
Triangle
Park,
NC
76
42773802
Waring,
A.
R.
1993b.
[
14C]
Oxadiazon:
Anaerobic
aquatic
metabolism.
HUK
Study
No.
68/
112;
Report
No.
7214.
Unpublished
study
performed
by
Hazleton
UK,
Harrogate,
North
Yorkshire,
England,
and
submitted
by
Rhône­
Poulenc
Agriculture
Company,
Research
Triangle
Park,
NC
77
Appendix
E.
Generic
Data
Call­
in
78
Appendix
F.
Product­
specific
Data
Call­
in
79
Appendix
G.
EPA's
Batching
of
Oxadiazon
Products
for
Meeting
Acute
Toxicity
Data
Requirements
for
Reregistration
80
EPA'S
BATCHING
OF
OXADIAZON
PRODUCTS
FOR
MEETING
ACUTE
TOXICITY
DATA
REQUIREMENTS
FOR
REREGISTRATION
In
an
effort
to
reduce
the
time,
resources
and
number
of
animals
needed
to
fulfill
the
acute
toxicity
data
requirements
for
reregistration
of
products
containing
Oxadiazon
the
primary
active
ingredient,
the
Agency
has
batched
products
which
can
be
considered
similar
for
purposes
of
acute
toxicity.
Factors
considered
in
the
sorting
process
include
each
product's
active
and
inert
ingredients
(
identity,
percent
composition
and
biological
activity),
type
of
formulation
(
e.
g.,
emulsifiable
concentrate,
aerosol,
wettable
powder,
granular,
etc.),
and
labeling
(
e.
g.,
signal
word,
use
classification,
precautionary
labeling,
etc.).
Note
the
Agency
is
not
describing
batched
products
as
"
substantially
similar"
since
some
products
with
in
a
batch
may
not
be
considered
chemically
similar
or
have
identical
use
patterns.

Using
available
information,
batching
has
been
accomplished
by
the
process
described
in
the
preceding
paragraph.
Notwithstanding
the
batching
process,
the
Agency
reserves
the
right
to
require,
at
any
time,
acute
toxicity
data
for
an
individual
product
should
need
arise.

Registrants
of
products
within
a
batch
may
choose
to
cooperatively
generate,
submit
or
cite
a
single
battery
of
six
acute
toxicological
studies
to
represent
all
the
products
within
that
batch.
It
is
the
registrants'
option
to
participate
in
the
process
with
all
other
registrants,
only
some
of
the
other
registrants,
or
only
their
own
products
within
in
a
batch,
or
to
generate
all
the
required
acute
toxicological
studies
for
each
of
their
own
products.
If
the
registrant
chooses
to
generate
the
data
for
a
batch,
he/
she
must
use
one
of
the
products
within
the
batch
as
the
test
material.
If
the
registrant
chooses
to
rely
upon
previously
submitted
acute
toxicity
data,
he/
she
may
do
so
provided
that
the
data
base
is
complete
and
valid
by
to­
days
standards
(
see
acceptance
criteria
attached),
the
formulation
tested
is
considered
by
EPA
to
be
similar
for
acute
toxicity,
and
the
formulation
has
not
been
significantly
altered
since
submission
and
acceptance
of
the
acute
toxicity
data.
Regardless
of
whether
new
data
is
generated
or
existing
data
is
referenced,
the
registrants
must
clearly
identify
the
test
material
by
EPA
Registration
Number.
If
more
than
one
confidential
statement
of
formula
(
CSF)
exists
for
a
product,
the
registrant
must
indicate
the
formulation
actually
tested
by
identifying
the
corresponding
CSF.

In
deciding
how
to
meet
the
product
specific
data
requirements,
registrants
must
follow
the
directions
given
in
the
Data
Call­
In
Notice
and
its
attachments
appended
to
the
RED.
The
DCI
Notice
contains
two
response
forms
which
are
to
be
completed
and
submitted
to
the
Agency
within
90
days
of
receipt.
The
first
form,
"
Data
Call­
in
Response,
"
asks
whether
the
registrant
will
meet
the
data
requirements
for
each
product.
The
second
form,
"
Requirements
Status
and
Registrant's
Response,"
lists
the
product
specific
data
required
for
each
product,
including
the
standard
six
acute
toxicity
tests.
A
registrant
who
wishes
to
participate
in
a
batch
must
decide
whether
he/
she
will
provide
the
data
or
depend
on
someone
else
to
do
so.
If
the
registrant
supplies
the
data
to
support
a
batch
of
products,
he/
she
must
select
the
one
of
the
following
options:
Developing
data
(
Option
1),
81
Submitting
an
existing
Study
(
Option
4),
Upgrading
an
existing
Study
(
Option
5),
or
Citing
an
Existing
Study
(
Option
).
If
a
registrant
depends
on
another's
data,
he/
she
must
choose
among:
Cost
sharing
(
Option
2),
Offers
to
Cost
Share
(
Option
3)
or
Citing
an
Existing
Study
(
Option
6).
If
a
registrant
does
not
want
to
participate
in
a
batch,
the
choices
are
Options
1,
4,
5
or
6.
However,
a
registrant
should
know
that
choosing
not
to
participate
in
a
batch
does
not
preclude
other
registrants
in
the
batch
from
citing
his/
her
studies
and
offering
to
cost
share
(
Option
3)
those
studies.

Forty
six
products
were
found
which
contain
Oxadiazon
as
the
active
ingredient.
These
products
have
been
placed
into
five
batches
and
a
No
batch
in
accordance
with
the
active
and
inert
ingredients
and
type
of
formulation.

Batch
1
EPA
Reg.
No.
Percent
active
ingredient
Formulation
Type
264­
502
50.0
Solid
432­
887
50.0
Solid
432­
893
50.0
Solid
Batch
2
EPA
Reg.
No.
Percent
active
ingredient
Formulation
Type
8660­
36
1.0
Solid
35512­
44
1.0
Solid
Batch
3
EPA
Reg.
No.
Percent
active
ingredient
Formulation
Type
961­
379
1.0
Solid
8378­
61
1.0
Solid
8660­
17
1.0
Solid
10404­
63
1.0
Solid
34704­
833
1.0
Solid
82
52287­
1
0.95
Solid
52287­
14
1.20
Solid
67508­
1
1.0
Solid
Batch
4
EPA
Reg.
No.
Percent
active
ingredient
Formulation
Type
52287­
10
Oxadiazon
­
0.500
Benefin
­
0.375
Trifluralin
­
0.375
Solid
52267­
11
Oxadiazon
­
0.75
Benefin
­
0.25
Trifluralin
­
0.25
Solid
52287­
12
Oxadiazon
­
1.00
Benefin
­
0.25
Trifluralin
­
0.25
Solid
Batch
5
EPA
Reg.
No.
Percent
active
ingredient
Formulation
Type
961­
371
Oxadiazon
­
0.50
Solid
961­
382
Oxadiazon
­
0.69
Solid
10404­
93
Oxadiazon
­
0.63
Solid
34704­
834
Oxadiazon
­
0.67
Solid
52287­
3
Oxadiazon
­
0.67
Solid
52287­
9
Oxadiazon
­
0.75
Solid
83
No
Batch
EPA
Reg.
No.
Percent
active
ingredient
Formulation
Type
264­
450
94.0
Solid
432­
886
2.0
Solid
432­
898
2.0
Solid
538­
146
4.0
Solid
538­
147
8.0
Solid
538­
164
Oxadiazon
­
1.31
Bensulide
­
5.25
Solid
538­
257
Oxadiazon
­
2.0
Pendimethalin
­
0.62
Solid
961­
340
1.73
Solid
961­
380
1.50
Solid
8378­
62
1.50
Solid
9198­
75
1.38
Solid
9198­
154
Oxadiazon
­
1.0
Dithiopyr
­
0.125
Solid
9198­
155
Oxadiazon
­
1.0
Dithiopyr
­
0.1875
Solid
9198­
176
Oxadiazon
­
1.31
Bensulide
­
5.25
Solid
9198­
185
2.75
Solid
9198­
203
1.5
Solid
10404­
97
Oxadiazon
­
1.0
Dithiopyr
­
0.15
Solid
34704­
771
Oxadiazon
­
2.0
Napropamide
­
4.0
Solid
35512­
43
2.0
Solid
48234­
1
Oxadiazon
­
1.0
Balfin
­
0.5
Solid
48234­
2
2.0
Solid
84
48234­
10
Oxadiazon
­
1.0
Oxyfluorfen
­
2.0
Solid
48234­
14
1.0
Solid
48234­
15
Oxadiazon
­
1.0
Prodiamine
­
0.2
Solid
85
Appendix
H.
List
of
Registrants
Sent
this
Data
Call­
in
86
Appendix
I.
List
of
Available
Related
Documents
and
Electronically
Available
Forms
87
Appendix
I.
LIST
OF
AVAILABLE
RELATED
DOCUMENTS
AND
ELECTRONICALLY
AVAILABLE
FORMS
Pesticide
Registration
Forms
are
available
at
the
following
EPA
internet
site:

http://
www.
epa.
gov/
opprd001/
forms/

Pesticide
Registration
Forms
(
These
forms
are
in
PDF
format
and
require
the
Acrobat
reader)

Instructions
1.
Print
out
and
complete
the
forms.
(
Note:
Form
numbers
that
are
bolded
can
be
filled
out
on
your
computer
then
printed.)

2.
The
completed
form(
s)
should
be
submitted
in
hardcopy
in
accord
with
the
existing
policy.

3.
Mail
the
forms,
along
with
any
additional
documents
necessary
to
comply
with
EPA
regulations
covering
your
request,
to
the
address
below
for
the
Document
Processing
Desk.

DO
NOT
fax
or
e­
mail
any
form
containing
'
Confidential
Business
Information'
or
'
Sensitive
Information.'

If
you
have
any
problems
accessing
these
forms,
please
contact
Nicole
Williams
at
(
703)
308­
5551
or
by
e­
mail
at
williams.
nicole@
epa.
gov.

The
following
Agency
Pesticide
Registration
Forms
are
currently
available
via
the
internet:

at
the
following
locations:

8570­
1
Application
for
Pesticide
Registration/
Amendment
http://
www.
epa.
gov/
opprd001/
forms/
8570­
1.
pdf
8570­
4
Confidential
Statement
of
Formula
http://
www.
epa.
gov/
opprd001/
forms/
8570­
4.
pdf
8570­
5
Notice
of
Supplemental
Registration
of
Distribution
of
a
Registered
Pesticide
Product
http://
www.
epa.
gov/
opprd001/
forms/
8570­
5.
pdf
8570­
17
Application
for
an
Experimental
Use
Permit
http://
www.
epa.
gov/
opprd001/
forms/
8570­
17.
pdf
88
8570­
25
Application
for/
Notification
of
State
Registration
of
a
Pesticide
To
Meet
a
Special
Local
Need
http://
www.
epa.
gov/
opprd001/
forms/
8570­
25.
pdf
8570­
27
Formulator's
Exemption
Statement
http://
www.
epa.
gov/
opprd001/
forms/
8570­
27.
pdf
8570­
28
Certification
of
Compliance
with
Data
Gap
Procedures
http://
www.
epa.
gov/
opprd001/
forms/
8570­
28.
pdf
8570­
30
Pesticide
Registration
Maintenance
Fee
Filing
http://
www.
epa.
gov/
opprd001/
forms/
8570­
30.
pdf
8570­
32
Certification
of
Attempt
to
Enter
into
an
Agreement
with
other
Registrants
for
Development
of
Data
http://
www.
epa.
gov/
opprd001/
forms/
8570­
32.
pdf
8570­
34
Certification
with
Respect
to
Citations
of
Data
(
PR
Notice
98­
5)
http://
www.
epa.
gov/
opppmsd1/
PR_
Notices/
pr98­
5.
pdf
8570­
35
Data
Matrix
(
PR
Notice
98­
5)
http://
www.
epa.
gov/
opppmsd1/
PR_
Notices/
pr98­
5.
pdf
8570­
36
Summary
of
the
Physical/
Chemical
Properties
(
PR
Notice
98­
1)
http://
www.
epa.
gov/
opppmsd1/
PR_
Notices/
pr98­
1.
pdf
8570­
37
Self­
Certification
Statement
for
the
Physical/
Chemical
Properties
(
PR
Notice
98­
1)
http://
www.
epa.
gov/
opppmsd1/
PR_
Notices/
pr98­
1.
pdf
Pesticide
Registration
Kit
www.
epa.
gov/
pesticides/
registrationkit/

Dear
Registrant:

For
your
convenience,
we
have
assembled
an
online
registration
kit
which
contains
the
following
pertinent
forms
and
information
needed
to
register
a
pesticide
product
with
the
U.
S.
Environmental
Protection
Agency's
Office
of
Pesticide
Programs
(
OPP):

1.
The
Federal
Insecticide,
Fungicide,
and
Rodenticide
Act
(
FIFRA)
and
the
Federal
Food,
Drug
and
Cosmetic
Act
(
FFDCA)
as
Amended
by
the
Food
Quality
Protection
Act
(
FQPA)
of
1996.

2.
Pesticide
Registration
(
PR)
Notices
a.
83­
3
Label
Improvement
Program­­
Storage
and
Disposal
Statements
b.
84­
1
Clarification
of
Label
Improvement
Program
89
c.
86­
5
Standard
Format
for
Data
Submitted
under
FIFRA
d.
87­
1
Label
Improvement
Program
for
Pesticides
Applied
through
Irrigation
Systems
(
Chemigation)
e.
87­
6
Inert
Ingredients
in
Pesticide
Products
Policy
Statement
f.
90­
1
Inert
Ingredients
in
Pesticide
Products;
Revised
Policy
Statement
g.
95­
2
Notifications,
Non­
notifications,
and
Minor
Formulation
Amendments
h.
98­
1
Self
Certification
of
Product
Chemistry
Data
with
Attachments
(
This
document
is
in
PDF
format
and
requires
the
Acrobat
reader.)

Other
PR
Notices
can
be
found
at
http://
www.
epa.
gov/
opppmsd1/
PR_
Notices
3.
Pesticide
Product
Registration
Application
Forms
(
These
forms
are
in
PDF
format
and
will
require
the
Acrobat
reader).

a.
EPA
Form
No.
8570­
1,
Application
for
Pesticide
Registration/
Amendment
b.
EPA
Form
No.
8570­
4,
Confidential
Statement
of
Formula
c.
EPA
Form
No.
8570­
27,
Formulator's
Exemption
Statement
d.
EPA
Form
No.
8570­
34,
Certification
with
Respect
to
Citations
of
Data
e.
EPA
Form
No.
8570­
35,
Data
Matrix
4.
General
Pesticide
Information
(
Some
of
these
forms
are
in
PDF
format
and
will
require
the
Acrobat
reader).

a.
Registration
Division
Personnel
Contact
List
b.
Biopesticides
and
Pollution
Prevention
Division
(
BPPD)
Contacts
d.
Antimicrobials
Division
Organizational
Structure/
Contact
List
d.
53
F.
R.
15952,
Pesticide
Registration
Procedures;
Pesticide
Data
Requirements
(
PDF
format)
e.
40
CFR
Part
156,
Labeling
Requirements
for
Pesticides
and
Devices
(
PDF
format)
f.
40
CFR
Part
158,
Data
Requirements
for
Registration
(
PDF
format)
g..
50
F.
R.
48833,
Disclosure
of
Reviews
of
Pesticide
Data
(
November
27,
1985)

Before
submitting
your
application
for
registration,
you
may
wish
to
consult
some
additional
sources
of
information.
These
include:

1.
The
Office
of
Pesticide
Programs'
website.

2.
The
booklet
"
General
Information
on
Applying
for
Registration
of
Pesticides
in
the
United
States",
PB92­
221811,
available
through
the
National
Technical
Information
Service
(
NTIS)
at
the
following
address:
90
National
Technical
Information
Service
(
NTIS)

5285
Port
Royal
Road
Springfield,
VA
22161
The
telephone
number
for
NTIS
is
(
703)
605­
6000.

3.
The
National
Pesticide
Information
Retrieval
System
(
NPIRS)
of
Purdue
University's
Center
for
Environmental
and
Regulatory
Information
Systems.
This
service
does
charge
a
fee
for
subscriptions
and
custom
searches.
You
can
contact
NPIRS
by
telephone
at
(
765)
494­
6614
or
through
their
website.

4.
The
National
Pesticide
Information
Center
(
NPIC)
can
provide
information
on
active
ingredients,
uses,
toxicology,
and
chemistry
of
pesticides.
You
can
contact
NPIC
by
telephone
at
(
800)
858­
7378
or
through
their
website:
http://
npic.
orst.
edu..

The
Agency
will
return
a
notice
of
receipt
of
an
application
for
registration
or
amended
registration,
experimental
use
permit,
or
amendment
to
a
petition
if
the
applicant
or
petitioner
encloses
with
his
submission
a
stamped,
self­
addressed
postcard.
The
postcard
must
contain
the
following
entries
to
be
completed
by
OPP:

$
Date
of
receipt;

$
EPA
identifying
number;
and
$
Product
Manager
assignment.

Other
identifying
information
may
be
included
by
the
applicant
to
link
the
acknowledgment
of
receipt
to
the
specific
application
submitted.
EPA
will
stamp
the
date
of
receipt
and
provide
the
EPA
identifying
file
symbol
or
petition
number
for
the
new
submission.
The
identifying
number
should
be
used
whenever
you
contact
the
Agency
concerning
an
application
for
registration,
experimental
use
permit,
or
tolerance
petition.

To
assist
us
in
ensuring
that
all
data
you
have
submitted
for
the
chemical
are
properly
coded
and
assigned
to
your
company,
please
include
a
list
of
all
synonyms,
common
and
trade
names,
company
experimental
codes,
and
other
names
which
identify
the
chemical
(
including
"
blind"
codes
used
when
a
sample
was
submitted
for
testing
by
commercial
or
academic
facilities).
Please
provide
a
chemical
abstract
system
(
CAS)
number
if
one
has
been
assigned.

Documents
Associated
with
this
RED
The
following
documents
are
part
of
the
Administrative
Record
for
this
RED
document
and
may
be
included
in
the
EPA's
Office
of
Pesticide
Programs
Public
Docket.
Copies
of
these
documents
are
not
91
available
electronically,
but
may
be
obtained
by
contacting
the
person
listed
on
the
respective
Chemical
Status
Sheet.

1.
Health
Effects
Division
and
Environmental
Fate
and
Effects
Division
Science
Chapters,
which
include
the
complete
risk
assessments
and
supporting
documents.

2.
Detailed
Label
Usage
Information
System
(
LUIS)
Report.
