UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON,
D.
C.
20460
OFFICE
OF
PREVENTION,
PESTICIDES
AND
TOXIC
SUBSTANCES
Date:
July
15,
2001
MEMORANDUM
SUBJECT:
REVISED
OCCUPATIONAL
AND
RESIDENTIAL
EXPOSURE
ASSESSMENT
AND
RECOMMENDATIONS
FOR
THE
REREGISTRATION
ELIGIBILITY
DECISION
DOCUMENT
FOR
OXADIAZON
FROM:
Seyed
Tadayon,
Chemist
Chemistry
Exposure
Branch
I
Health
Effect
Division
(
7509C)

THRU:
Francis
Suhre,
Senior
Scientist
Chemistry
Exposure
Branch
I
Health
Effects
Division
(
7509C)

TO:
Nancy
McCarroll,
Geneticist
Toxicology
Branch
I
Health
Effects
Division
(
7509C)

Please
find
the
review
of
oxadiazon.
DP
Barcode:
D276360
PC
Codes:
109001
EPA
Reg
Nos:
264­
450,
264­
502,
432­
886,
432­
887,
432­
893,
432­
898,
538­
143,
538­
146,
538­
147,
538­
164,
538­
241,
538­
257,
961­
340,
961­
371,
961­
379,
961­
380,
961­
382,
8660­
17,
8660­
35,
8660­
36,
9198­
75,
9198­
154,
9198­
155,
10404­
63,
10404­
93,
34704­
771,
35512­
43,
35512­
44,
48234­
1,
48234­
2,
48234­
10,
48234­
14,
48234­
15,
52287­
1,
52287­
2,
52287­
3,
55615­
4,
55615­
5,
67508­
1,
CA97001800,
FL82004500,
HI97000100.

EPA
MRID
No:
449955­
01,
449955­
02,
435178­
01
LUIS
Report:
05/
04/
99
PHED:
Yes,
Version
1.1
2
CONTENTS
EXECUTIVE
SUMMARY
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3
1.0
BACKGROUND
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6
1.1
Summary
of
Toxicity
Concerns
Relating
to
Agricultural
Exposures
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6
1.2
Summary
of
Use
Pattern
and
Formulations
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8
1.3
Method
and
Types
of
Equipment
Used
for
Mixing/
Loading/
Applying
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10
1.4
Incident
Reports
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10
2.0
OCCUPATIONAL
EXPOSURES
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12
2.1
Handler
Exposures
&
Assumptions
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12
2.1.1
Summary
of
Occupational
Handler
Exposures
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14
2.1.2
Summary
of
Uncertainties
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17
2.1.3
Calculations
of
Exposure
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17
2.1.4
Calculations
of
Cancer
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18
2.2
Risk
From
Handler
Exposures
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19
2.2.1
Risk
From
Handler
Exposures
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20
2.2.2
Summary
of
MOEs
and
cancer
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22
3.0
POSTAPPLICATION
EXPOSURES
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27
3.1
Postapplication
Exposures
&
Assumptions
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27
3.1.1
Data
Source
and
Assumptions
For
Scenario
Considered
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27
3.1.2
Assumptions
Used
in
Postapplication
Exposure
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28
3.1.3
Exposure
and
Risk
Calculation
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28
3.1.4
Postapplication
Exposure
Risk
estimates
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29
3.2
Non­
occupational
Postapplication
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29
3.2.1
Postapplication
Exposure
Scenarios
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30
3.2.2
Data
Sources
for
Scenarios
Considered
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30
3.2.3
Assumptions
Used
in
Postapplication
Exposure
Calculations
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31
3.2.4
Postapplication
Exposure
Risk
Estimates
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36
3.2.5
Data
Gaps
and
Uncertainties
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36
APPENDIX
A
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37
APPENDIX
B
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47
APPENDIX
C
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56
REFERENCES
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61
EXECUTIVE
SUMMARY
3
Purpose
This
is
a
revision
of
the
original
Occupational
and
Residential
Exposure
Assessment
and
Recommendations
Document
for
Oxadiazon,
(
S.
Tadayon
June
12,
2001).
This
chapter
has
been
revised
to
address
comments
made
by
the
Risk
Assessment
Review
Committee
(
RARC).

This
document
addresses
the
exposures
and
risks
associated
with
the
use
of
the
oxadiazon,
that
occur
through
non­
dietary
exposure.
These
exposures
can
occur
as
a
result
of
applying
oxadiazon
or
by
entering
areas
that
have
been
previously
treated
with
oxadiazon.
Exposures
can
occur
as
a
part
of
one's
job
or
through
uses
of
oxadiazon
on
residential
lawns
and
other
areas
that
are
frequented
by
the
general
public.
Occupational
and
residential
exposures
are
addressed
separately
in
this
document.

Oxadiazon,
2­
tert­
butyl­
4­
(
2,4­
dichloro­
5­
isopropoxyphenyl­
1,3,4­
oxadiazolin­
5­
one),
is
a
selective
pre
emergence
and
early
post
emergence
herbicide
used
primarily
to
control
annual
grasses
and
broadleaf
weeds.
The
occupational
use
sites
include
golf
course
turf,
ornamental
turf,
conifer
nursery,
landscape
­
industrial
sites,
ornamental
noncroplands,
roadside
landscape
plantings,
sod
farms,
woody
ornamental
shrubs,
vines
and
trees
and
herbaceous
ornamental
crops.
The
outdoor
residential
use
site
include
cemeteries,
athletic
fields,
residential
condominiums
and
school
ground.
A
wide
variety
of
application
techniques
have
been
identified
that
could
potentially
be
used
to
apply
oxadiazon
such
as
groundboom
sprayers,
handheld
sprayers
(
low
and
high
pressure
devices
and
low
pressure/
high
volume
sprayguns
commonly
used
on
turf),
backpack
sprayers,
tractor­
drawn
granular
spreaders,
push­
type
granular
lawn
spreaders,
and
bellygrinders.
Oxadiazon
is
formulated
as
a
manufacturing
product
(
94.0%
active
ingredient),
several
granular
formulations
(
up
to
50.0%
active
ingredient)
and
three
wettable
powders
(
50.0%
active
ingredient).

Hazard
Identification
The
Report
of
the
Hazard
Identification
Assessment
Review
Committee
(
HIARC)
for
oxadiazon,
dated
December
21,
2000,
indicates
that
there
are
toxicological
endpoints
of
concern
for
oxadiazon.
A
short­
term
(
1­
7
days)
to
intermediate­
term
(
one
week
to
several
months)
oral
endpoint
was
selected
for
incidental
oral
exposure
in
children,
using
a
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.

For
short­
term
and
intermediate
dermal
exposure,
an
oral
endpoint
was
selected
using
a
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.
The
committee
recommended
a
dermal
absorption
factor
of
9%
(
rounded
up
from
8.7%)
based
on
a
dermal
penetration
study
to
be
used
in
the
calculation.

Due
to
a
lack
of
inhalation
studies,
the
HIARC
selected
an
endpoint
from
oral
studies
for
4
inhalation
risk
assessments.
For
short
and
intermediate­
term
inhalation
exposure,
the
same
oral
study
was
chosen
as
for
dermal
exposure
of
this
duration,
with
a
NOAEL
of
12
mg/
kg/
day.
An
absorption
factor
of
100%
is
applied
for
inhalation
exposures.
The
target
margin
of
exposure
(
MOE)
of
100
or
more
for
occupational
exposure
scenarios
was
selected
based
upon
10x
for
intraspecies
and
10x
for
interspecies
variation.
Because
the
effects
from
dermal
and
inhalation
exposure
are
the
same,
the
doses
for
these
routes
and
duration
may
be
aggregated.

Since
1987,
the
Agency's
decision
on
the
carcinogenic
potential
of
oxadiazon
concurred
with
the
Scientific
Advisory
Panel's
(
SAP)
classification
of
oxadiazon
as
a
Group
C
carcinogen
and
the
Q
1*
had
been
set
at
1.4
x
10­
1(
mg/
kg/
day)­
1
in
human
equivalents.
Since
that
time,
new
chronic/
carcinogenicity
data
have
been
submitted
and
reviewed
by
the
Cancer
Assessment
Review
Committee
(
CARC).
Based
on
this
revisit,
CARC
has
reclassified
oxadizon
as
a
"
Likely
To
Be
Carcinogenic
To
Humans".
For
the
purpose
of
the
lifetime
cancer
risk
assessment
by
the
Agency,
the
most
potent
unit
risk,
Q
1
*,
is
that
for
male
mouse
liver
adenoma
and/
or
carcinoma
combined
tumor
rates
at
7.11
x
10­
2
(
mg/
kg/
day)­
1
in
human
equivalents.
All
unit
risks
have
been
converted
from
animals
to
humans
by
use
of
the
3/
4'
s
scaling
factor.

Oxadiazon
has
not
been
reported
to
cause
life­
threatening
illness
or
death.
Most
of
the
cases
appear
to
be
related
to
irritation
to
the
skin,
eyes
and
mucous
membranes.
Some
cases
may
be
related
to
an
allergic
reaction
On
the
list
of
the
top
200
chemicals
for
which
NPTN
(
National
Pesticide
Telecommunications
Network)
received
calls
from
1984­
1991
inclusively,
oxadiazon
was
ranked
192nd
with
12
incidents
in
humans
reported
and
5
incidents
in
animals
(
mostly
pets).

Occupational
Handler
Exposure
and
Risk
Estimates
HED
has
determined
that
there
are
potential
exposures
to
mixers,
loaders,
applicators,
and
other
handlers
during
usual
use­
patterns
associated
with
oxadiazon.
Fourteen
major
exposure
scenarios
were
identified
for
oxadiazon,
including
mixing,
loading,
and
applying
using
ground
spray,
granular,
and
lawn
application
methods.

Handler
Scenarios
with
Risk
Concerns
The
results
of
the
short
and
intermediate­
term
handler
assessments
indicate
that
all
potential
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).
In
the
majority
of
cases,
it
is
dermal
exposure
rather
than
the
inhalation
exposure
driving
the
total
MOEs.
In
total,
37
MOEs
were
calculated
for
the
various
application
rates.
The
total
MOEs
for
all
the
scenarios
range
from
2
to
3000.

The
results
of
the
Cancer
Risk
indicate
that
the
values
range
from
1.65E­
2
to
4.66E­
7
at
the
baseline
(
i.
e.
long
pants,
long
shirts
and
no
gloves),
2.56E­
3
to
4.11E­
7
at
PPE1
(
i.
e.
long
5
pants,
long
shirts,
gloves
and
no
respirator),
2.40E­
3
to3.51E­
7
at
PPE2
(
i.
e.
long
pants,
long
shirts,
double
layer,
gloves
and
no
respirator),
1.05E­
3
to
1.98E­
7
at
PPE3
(
i.
e.
long
pants,
long
shirts,
gloves
and
respirator),
8.90E­
4
to
1.38E­
07
at
PPE4
(
i.
e.
long
pants,
long
shirts,
double
layer,
gloves
and
respirator)
and
4.92E­
5
to
1.10E­
8
at
engineering
control.

Postapplication
Worker
Exposure
and
Risk
Estimates
Most
of
the
oxadiazon
used
on
golf
course
turf
(
71%),
ornamental
turf,
conifer
nursery,
landscape
­
industrial
sites,
ornamental
non­
croplands,
roadside
landscape
planting,
sod
farms,
woody
ornamental
shrubs,
vines
and
trees
and
herbaceous
ornamental
crops
is
applied
early
in
the
season,
either
pre­
plant
or
before
weeds
emerge
(
pre­
emergence).
This
fact,
and
the
degree
of
mechanization
in
cultivating
these
crops,
minimizes
the
postapplication
contact
of
workers
with
the
chemical
on
these
crops.
Three
chemical­
specific
studies,
were
submitted
to
the
Agency
for
consideration.
Theses
studies
were
reviewed
and
only
the
re­
entry
study
found
to
be
acceptable
for
use
in
the
oxadiazon
risk
assessment.

Using
the
revised
residential
SOP
postapplication
short­
and
intermediate­
term
dermal
risk
estimates
for
occupational
workers
are
between
30
and
1,000.
The
cancer
risk
for
all
occupational
handlers
is
between
9.92
x
10­
5
to
3.01
x
10­
6.

Residential
Postapplication
Exposure
and
Risk
Estimates
Dermal
postapplication
exposure
estimates
were
conducted
using
the
highest
mean
postapplication
residue
from
the
Jazzercise
study
(
wettable
powder
formulations).
The
dermal
transfer
coefficients
from
the
Jazzercize
study
and
the
revised
residential
SOPs
were
used.
Using
the
Jazzercize
wettable
powder
application
study
residue
data
and
revised
residential
SOPs
,
all
of
the
scenario
had
short­
term
and
intermediate
dermal
MOEs
greater
than
100.
The
cancer
risks
for
all
residential
dermal
postapplication
is
between
6.22x
10­
6
to
7.51
x
10­
7
.

The
Residential
SOPs
and
submitted
Jazzercize
study
data
were
used
to
estimate
incidental
oral
exposure
for
toddlers
on
treated
turf.
The
short­
term
MOE
was100
for
the
toddler
hand­
to­
mouth
using
residential
SOPs
and
between
90
to
240
for
the
submitted
study.
The
intermediate­
term
MOE
was
not
calculated
since
exposure
by
this
route
for
weeks
to
months
is
considered
less
likely
to
occur
than
short­
term
exposure.
Incidental
turfgrass
mouthing
and
soil
ingestion
had
MOEs
greater
than
100
for
short­
term
exposures.

Uncertainties
in
Risk
Assessment
and
Data
Gaps
Residential
handler
exposure
and
risk
estimates
were
conducted
using
a
set
of
surrogate
chemical
data:
the
ORETF
study
data
and
the
Residential
SOPs.
Dermal
postapplication
exposures
to
oxadiazon
were
based
on
the
highest
residues
from
the
chemical­
specific
re­
entry
study
data
and
are
of
fairly
high
confidence.
Oral
ingestion
scenarios
are
based
on
standard
assumptions
and
formulae
(
Residential
SOPs)
which
are
designed
to
be
screening
level.
Granular
6
ingestion
is
considered
episodic
in
nature.

1.0
BACKGROUND
Purpose
In
this
document,
which
is
for
use
in
EPA's
development
of
the
oxadizon.
Reregistration
Eligibility
Decision
Document
(
RED),
EPA
presents
the
results
of
its
review
of
the
potential
human
health
effects
of
occupational
and
residential
exposure
to
oxadiazon.

Criteria
for
Conducting
Exposure
Assessments
An
occupational
and/
or
residential
exposure
assessment
is
required
for
an
active
ingredient
if
(
1)
certain
toxicological
criteria
are
triggered
and
(
2)
there
is
potential
exposure
to
handlers
(
mixers,
loaders,
applicators,
etc.)
during
use
or
to
persons
entering
treated
sites
after
application
is
complete.
For
oxadiazon,
both
criteria
are
met.

1.1
Summary
of
Toxicity
Concerns
Relating
to
Agricultural
Exposures
Acute
Toxicology
Categories
Table
1
presents
the
acute
toxicity
categories
as
outlined
in
the
Hazard
Identification
Document
(
Dec
21,
2000).
1
Table
1:
Acute
Toxicity
Categories
For
Oxadiazon
Guideline
No.
Study
Type
MRID
#(
S).
Results
Toxicity
Category
81­
1
Acute
Oral­
Rat
41866501
LD50
=
>
5000
mg/
kg
(


,
combined)
IV
81­
2
Acute
Dermal­
Rabbit
41866502
LD50
=
>
2000
mg/
kg
(


,
combined)
III
81­
3
Acute
Inhalation­
Rat
41866503
LC50
=
>
1.94
mg/
L
(


,
combined)
III
81­
4
Primary
Eye
Irritation­
Rabbit
41866504
Mild
irritant
to
ocular
tissue
III
81­
5
Primary
Skin
Irritation­
Rabbit
41866505
Negligibly
irritating
to
skin
III
81­
6
Dermal
Sensitization­
Guinea
Pig
41230401
Not
a
dermal
sensitizer
(
Buehler
test)
­­

81­
8
Acute
Neurotoxicity
ND
Other
Endpoints
of
Concern
The
report
of
the
Hazard
Identification
Assessment
Review
Committee
(
HIARC)
for
oxadiazon,
dated
Dec
21,
20001,
identified
toxicological
endpoints
of
concern
for
oxadiazon.
7
All
calculations
completed
in
this
document
are
based
on
the
most
current
toxicity
information
available
for
oxadiazon.
The
endpoints
that
were
used
to
complete
this
assessment
are
summarized
below
in
Table
2:

Table
2:
Endpoints
selected
by
HIARC
for
Assessing
Occupational
and
Residential
Risks
for
Oxadiazon
EXPOSURE
SCENARIO
DOSE
(
mg/
kg/
day)
ENDPOINT
STUDY
Incidental
Oral,
Short­
Term
NOAEL=
12
Maternal
effects
Reduced
body
weight/
body
weight
gain
at
40
mg/
kg/
day
(
LOAEL).
Developmental
Toxicity
­
Rat
MRID
No.
40470202
Incidental
Oral,
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
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,
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
Reduced
body
weight/
body
weight
gain
at
40
mg/
kg/
day
(
LOAEL)
/
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
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,
route­
to­
route
extrapolation
and
a
100%
absorption
rate
are
applied
Developmental
Toxicity
­
Rat
MRID
No.
40470202
Inhalation,
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,
route­
to­
route
extrapolation
and
a
100%
absorption
rate
are
applied.
Developmental
Toxicity
­
Rat
MRID
No.
40470202
Inhalation,
Long­
Term
NOAEL=
0.36
Increased
centrilobular
swelling
in
male
livers
at
3.5
mg/
kg/
day
(
LOAEL).
Route­
to­
route
extrapolation
and
a
100%
absorption
rate
aplied.
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
adenomas
and/
or
carcinomas
combined
in
males
at

9.3
mg/
kg/
day).
Combined
Chronic
Feeding/
Carcinogenicity
­
Mouse
MRID
Nos.
40993301
1.2
Summary
of
Use
Patterns
and
Formulations
At
this
time,
products
containing
oxadiazon
are
intended
for
both
occupational
and
residential
uses.
8
Type
of
pesticide/
target
pests
Oxadiazon,
2­
tert­
butyl­
4­
(
2,4­
dichloro­
5­
isopropoxyphenyl­
1,3,4­
oxadiazolin­
5­
one),
is
a
selective
pre­
emergence
and
early
post
emergence
herbicide
used
primarily
to
control
annual
grasses
and
broadleaf
weeds.
Table
3
presents
a
list
of
oxadiazons
'
s
active
products.
The
annual
grasses
and
broadleaves
controlled
by
oxadiazon
include
the
following:

1.
Annual
grasses:
annual
blugrass,
barnyardgrass,
crabgrass,
fall
panicum,
giant
foxtail
(
yellow
and
green),
goosegrass,
junglerice,
signalgrass,
sprangletop,
Texas
panicum
and
hophornbeam
copperleaf
$
Broadleaves:
Florida
beggarweed,
carpet
weed,
cudweed,
dayflower,
ducksalad,
filaree,
groundsel,
jimsonweed,
lambersquarters,
mustards,
pigweed,
prickly
sida,
prostrate
knotweed,
purslane,
purslane,
redmaids,
smartweed,
sowthistle,
velvetleaf,
morningglory
and
black
night
shade
Formulation
types
and
percent
active
ingredient
Oxadiazon
is
formulated
as
a
manufacturing
product
(
94.0%
active
ingredient),
several
granular
formulations
(
up
to
50.0%
active
ingredient)
and
three
wettable
powders
(
50.0%
active
ingredient).
Wettable
powders
are
marketed
in
bags
and
water
soluble
bags.

Registered
use
sites,
application
rates
and
frequency
of
application
Oxadiazon
is
applied
as
a
pre­
plant
or
pre­
emergent
herbicide
on
non­
food/
outdoor
crops.
occupational
applications
(
i.
e.,
to
turf
and
ornamentals)
are
made
to
established
areas
such
as
lawns
or
golf
course
greens
prior
to
the
emergence
of
the
target
plant
species.
Residential/
nonoccupational
applications
are
made
to
residential
lawns,
parks,
cemeteries,
schools,
athletic
fields
and
golf
courses.
The
frequency
of
application
ranges
from
1
to
3
applications
per
season.
Oxadiazon
can
be
applied
at
a
minimum
application
rate
of
2.0
pounds
of
active
ingredient
per
acre
up
to
a
maximum
application
rate
of
4.0
pounds
active
ingredient
per
acre
to
turf
and
ornamentals.
Oxadiazon
use
sites
are
non­
food
crops
(
primarily
golf
course
greens,
77%
of
all
use),
residential
outdoor
use
(
approximately
12%
of
all
use),
roadside
(
approximately
3%
of
all
use)
and
nurseries
(
approximately
8%
of
all
use).
The
granular
formulations
account
for
91%
of
the
total
oxadiazon
use
(
turf
use).

Table
3
represents
information
on
registered
use
sites,
products
name,
application
rates,
percent
active
ingredient
and
frequency
of
application
per
growing
season
for
oxadiazon2.
Application
rate
covers
various
type
of
equipment
used
to
apply
oxadiazon.

Table
3:
Use
Patterns,
Application
Rate,
and
Frequency
of
Application
for
Oxadiazon
Reg
No
A.
I
%
Product
Name
Crop
Type
Max
Appl
rate
No
of
Appl
per/
y
10404­
63
0.95
Lesco
Turfic
for
Crabgrass
with
Ronstar
G
turf:
golf
course
4
lb
ai/
acre
3
10404­
63
0.95
Lesco
Turfic
for
Crabgrass
with
RonstarG
turf:
ornamental
4
lb
ai/
acre
3
10404­
93
0.63
Ronstar
Weed
and
Feed
63
G
nursery:
woody
ornamental
shrubs,
vines
and
trees
4
lb
ai/
acre
3
9
10404­
93
0.63
Ronstar
Weed
and
Feed
63
G
nursery:
woody
ornamental
shrubs,
vines
and
trees
4
lb
ai/
acre
3
10404­
93
0.63
Ronstar
Weed
and
Feed
63
G
turf:
golf
course
4
lb
ai/
acre
3
10404­
93
0.63
Ronstar
Weed
and
Feed
63
G
turf:
ornamental
(
parks,
athletic
fields,
recreational)
4
lb
ai/
acre
3
10404­
93
0.63
Ronstar
Weed
and
Feed
63
G
turf:
sod
farms
4
lb
ai/
acre
3
264­
445
2
Chipco
Ronstar
G
nursery:
conifer
4
lb
ai/
acre
1
264­
445
2
Chipco
Ronstar
G
nursery:
woody
ornamentals,
shrubs,
vines
and
trees
4
lb
ai/
acre
1
264­
445
2
Chipco
Ronstar
G
turf:
golf
course
4
lb
ai/
acre
1
264­
445
2
Chipco
Ronstar
G
turf:
lawns
4
lb
ai/
acre
1
264­
445
2
Chipco
Ronstar
G
turf:
ornamental
(
parks)
4
lb
ai/
acre
1
264­
450
94
oxadiazon
technical
Formulating
use
only
264­
502
50
Ronstar
50%
Intermediate
Formulating
use
only
264­
538
50
Chipco
Ronstar
50
WSP
landscape:
woody
ornamental
shrubs,
vines
and
trees
2
lb
ai/
acre
1
264­
538
50
Chipco
Ronstar
50
WSP
nursery:
conifer
4
lb
ai/
acre
1
264­
538
50
Chipco
Ronstar
50
WSP
nursery:
woody
ornamental
shrubs,
vines
and
trees
4
lb
ai/
acre
1
264­
538
50
Chipco
Ronstar
50
WSP
turf:
golf
course
(
no
tees
and
greens)
3
lb
ai/
acre
3
264­
538
50
Chipco
Ronstar
50
WSP
turf:
ornamental
(
parks)
3
lb
ai/
acre
3
264­
538
50
Chipco
Ronstar
50
WSP
turf:
sod
farms
in
HI
3
lb
ai/
acre
3
34704­
771
2
Napropamide­
Oxadiazon
4­
2
Granules
landscape:
woody
ornamental
shurbs
vines
and
trees
3
lb
ai/
acre
34704­
771
2
Napropamide­
Oxadiazon
4­
2
Granules
nursery:
conifer
3
lb
ai/
acre
34704­
771
2
Napropamide­
Oxadiazon
4­
2
Granules
nursery:
woody
ornamental
shurbs
vines
and
trees
3
lb
ai/
acre
35512­
43
1
Turf
Pride
Fertilizer
with
Ronstar
5­
20G
turf:
golf
course
4
lb
ai/
acre
1
35512­
43
1
Turf
Pride
Fertilizer
with
Ronstar
5­
20G
turf:
ornamental
(
parks,
athletic
fields,
recreational)
4
lb
ai/
acre
1
35512­
43
1
Turf
Pride
Fertilizer
with
Ronstar
5­
20G
turf:
sod
farms
4
lb
ai/
acre
1
35512­
44
1
RegalstarG
turf:
established
2
lb
ai/
acre
1
35512­
44
1
RegalstarG
turf:
golf
course
2
lb
ai/
acre
1
48234­
1
1
RegalstarG
turf:
established
2
lb
ai/
acre
1
48234­
1
1
RegalstarG
turf:
golf
course
(
not
greens)
2
lb
ai/
acre
1
48234­
10
1
Regal­
O­
Herbicide
G
landscape:
woody
ornamental
shrubs,
vines
and
trees
3
lb
ai/
acre
48234­
10
1
Regal­
O­
Herbicide
G
nursery:
woody
ornamentals
shrubs,
trees,
vines
3
lb
ai/
acre
48234­
10
1
Regal
Ronstar
Plus
I
G
nursery:
woody
ornamentals
shrubs,
trees,
vines
4
lb
ai/
acre
3
48234­
10
1
Regal
Ronstar
Plus
I
G
turf:
golf
course
4
lb
ai/
acre
1
48234­
10
1
Regal
Ronstar
Plus
I
G
turf:
ornamental
4
lb
ai/
acre
1
48234­
15
1
RegalStar
II
G
landscape:
woody
ornamentals
shrubs,
trees,
vines
2
lb
ai/
acre
1
48234­
15
1
RegalStar
II
G
nursery:
woody
ornamentals
shrubs,
trees,
vines
2
lb
ai/
acre
1
48234­
15
1
RegalStar
II
G
turf:
golf
course
2
lb
ai/
acre
1
48234­
15
1
RegalStar
II
G
turf:
sod
farms
2
lb
ai/
acre
1
48234­
2
2
Regal
Ronstar
Plus
G
landscape:
woody
ornamental
shrubs,
vines
and
trees
4
lb
ai/
acre
1
48234­
2
2
Regal
Ronstar
Plus
G
nursery:
conifer
4
lb
ai/
acre
1
48234­
2
2
Regal
Ronstar
Plus
G
nursery:
woody
ornamental
shrubs,
vines
and
trees
4
lb
ai/
acre
3
48234­
2
2
Regal
Ronstar
Plus
G
turf:
golf
course
4
lb
ai/
acre
1
48234­
2
2
Regal
Ronstar
Plus
G
turf:
ornamental
(
parks)
4
lb
ai/
acre
1
52287­
1
0.95
Harrells
Crabgrass
Control
with
Ronstar
G
turf:
golf
course
4
lb
ai/
acre
3
52287­
1
0.95
Harrells
Crabgrass
Control
with
Ronstar
G
turf:
ornamental
4
lb
ai/
acre
3
52287­
2
1.5
Harrells
Ronstar
1.5
G
turf:
golf
course
4
lb
ai/
acre
3
52287­
2
1.5
Harrells
Ronstar
1.5
G
turf:
ornamental
4
lb
ai/
acre
3
52287­
3
0.67
Harrells
Ronstar
0.67
with
Fertilizer
G
turf:
golf
course
4
lb
ai/
acre
3
52287­
3
0.67
Harrells
Ronstar
0.67
with
FertilizerG
turf:
ornamental
4
lb
ai/
acre
3
538­
164
1.31
Scotts
ProTurf
Goosegrass/
Crabgrass
Control
8656
turf:
golf
course
(
fairways
and
greens)
0.75
538­
164
1.31
Scotts
ProTurf
Goosegrass/
Crabgrass
Control
8656
turf:
golf
course
(
fairways
and
tees)
1.5
538­
164
1.31
Scotts
ProTurf
Goosegrass/
Crabgrass
Control
8656G
turf:
golf
course
(
greens)
1.5
538­
164
1.31
Scotts
ProTurf
Goosegrass/
Crabgrass
Control
8656
turf:
ornamental
0.75
538­
241
~
1
Scotts
Turf
Starter
Plus
G
turf:
golf
course
fairways
4
lb
ai/
acre
1
538­
241
~
1
Scotts
Turf
Starter
Plus
G
turf:
ornamental
4
lb
ai/
acre
1
538­
257
0.2
Scotts
­
ProTurf
Fertilizer
Plus
Preemergent
Weed
Control
II
turf:
golf
course
4
lb
ai/
acre
2
538­
257
0.2
Scotts
­
ProTurf
Fertilizer
Plus
Preemergent
Weed
Control
II
turf:
ornamental
4
lb
ai/
acre
2
55615­
4
0.75
Wilbro
Fertilizer
with
0.75%
Ronstar
G
turf:
golf
course
4
lb
ai/
acre
1
55615­
4
0.75
Wilbro
Fertilizer
with
0.75%
Ronstar
G
turf:
ornamental
4
lb
ai/
acre
1
557­
1966
0.69
ParEx
Plus
Ronstar
G
turf:
golf
course
4
lb
ai/
acre
1
557­
1966
0.69
ParEx
Plus
Ronstar
G
turf:
ornamental
(
parks)
4
lb
ai/
acre
1
557­
1974
1.5
ParEx
Fertilizer
Plus
1.5%
RonstarG
turf:
golf
course
(
fairways)
4
lb
ai/
acre
1
557­
1974
1.5
ParEx
Fertilizer
Plus
1.5%
Ronstar
G
turf:
lawns
(
but
not
home
lawns)
4
lb
ai/
acre
1
557­
1974
1.5
ParEx
Fertilizer
Plus
1.5%
Ronstar
G
turf:
ornamental
(
parks)
4
lb
ai/
acre
1
557­
2026
1
ParEx
Fertilizer
Plus
1%
Ronstar
G
turf:
golf
course
4
lb
ai/
acre
1
557­
2026
1
ParEx
Fertilizer
Plus
1%
Ronstar
G
turf:
lawns
4
lb
ai/
acre
1
10
557­
2026
1
ParEx
Fertilizer
Plus
1%
Ronstar
G
turf:
ornamental
4
lb
ai/
acre
1
67508­
1
1
Ronstar
1%
with
Fertilizer
G
turf:
golf
course
4
lb
ai/
acre
1
67508­
1
1
Ronstar
1%
with
Fertilizer
G
turf:
ornamental
4
lb
ai/
acre
1
8660­
17
1
Sta­
Green
G
turf:
golf
course
2.5
1
8660­
17
1
Sta­
Green
G
turf:
lawns
2.5
1
8660­
36
1
Vertagreen
Fertilizer
with
Ronstar
G
turf:
golf
course
4
lb
ai/
acre
3
8660­
36
1
Vertagreen
Fertilizer
with
Ronstar
G
turf:
ornamental
4
lb
ai/
acre
3
9198­
154
1
Andersons
Fertilizer
with
1%
Ronstar
and
0.125%
Dimension
G
turf:
golf
course
(
fairways
and
roughs)
4
lb
ai/
acre
3
9198­
154
1
Andersons
Fertilizer
with
0.125%
Dimension
and
1.0%
Ronstar
G
turf:
golf
course
(
fairways)
2
lb
ai/
acre
3
9198­
154
1
Andersons
Fertilizer
with
0.125%
Dimension
and
1.0%
Ronstar
G
turf:
golf
course
(
roughs)
1.5
3
9198­
154
1
Andersons
Fertilizer
with
1%
Ronstar
and
0.125%
Dimension
G
turf:
lawns
4
lb
ai/
acre
3
9198­
154
1
Andersons
Fertilizer
with
1%
Ronstar
and
0.125%
Dimension
G
turf:
ornamental
4
lb
ai/
acre
3
9198­
75
1.38
Andersons
Fertilizer
with
1.38%
Ronstar
G
turf:
golf
course
(
fairways,
tees)
4
lb
ai/
acre
9198­
75
1.38
Andersons
Fertilizer
with
1.38%
Ronstar
G
turf:
golf
course(
fairways
and
tees)
4
lb
ai/
acre
9198­
75
1.38
Andersons
Fertilizer
with
1.38%
Ronstar
G
turf:
lawns
4
lb
ai/
acre
9198­
75
1.38
Andersons
Fertilizer
with
1.38%
Ronstar
G
turf:
ornamental
4
lb
ai/
acre
9198­
75
1.38
Andersons
Fertilizer
with
1.38%
Ronstar
G
turf:
ornamental
4
lb
ai/
acre
961­
340
1.73
Lebanon
Country
Club
with
Ronstar
G
landscape:
woody
ornamentals,
shrubs,
vines
4
lb
ai/
acre
3
961­
340
1.73
Lebanon
Country
Club
with
Ronstar
G
nursery:
conifer
4
lb
ai/
acre
3
961­
340
1.73
Lebanon
Country
Club
with
Ronstar
G
nursery:
woody
ornamentals
shrubs,
trees,
vines
4
lb
ai/
acre
3
961­
340
1.73
Lebanon
Country
Club
with
Ronstar
G
turf:
golf
course
4
lb
ai/
acre
1
961­
340
1.73
Lebanon
Country
Club
with
Ronstar
G
turf:
ornamental
(
parks
and
gardens)
4
lb
ai/
acre
1
961­
371
0.5
Lebanon
Country
Club
with
Ronstar
G
turf:
golf
course
4
lb
ai/
acre
961­
371
0.5
Lebanon
Country
Club
with
Ronstar
G
turf:
ornamental
4
lb
ai/
acre
CA­
970018
50
Chipco
Ronstar
50
WSP
landscape:
specific
ornamental
crops
3
lb
ai/
acre
NS
CA­
970018
50
Chipco
Ronstar
50
WSP
nursery:
specific
ornamental
crops
3
lb
ai/
acre
NS
FL­
820045
2
Chipco
Ronstar
G
leatherleaf
ferns
2
lb
ai/
acre
NS
HI­
970001
2
Chipco
Ronstar
G
turf:
Lalo
3
lb
ai/
acre
1
1.3
Methods
and
Types
of
Equipment
Used
for
Mixing/
Loading/
Applying
The
following
use
patterns
are
associated
with
the
application
equipment:
chemigation,
groundboom,
rights­
of­
way
sprayer,
handgun
sprayer,
tractor
drawn
spreader,
backpack
sprayer,
low
pressure
handwand,
high
pressure
handwand
lawn
handgun,
belly
grinder
and
push
type
spreader.
(
aerial
application
was
voluntarily
canceled
by
the
registrant)

1.4
Incident
reports
The
following
data
bases
have
been
consulted
for
the
poisoning
incident
data
on
the
active
ingredient
oxadiazon3.

I.
Incident
Data
System
Please
note
that
the
following
cases
from
the
IDS
do
not
have
documentation
confirming
exposure
or
health
effects
unless
otherwise
noted.

Incident#
6920­
2
A
pesticide
incident
occurred
in
1998,
when
a
man
applied
oxadiazon
on
a
wet
lawn.
He
reported
nausea,
headache,
and
difficulty
breathing.
No
further
information
on
the
disposition
of
the
case
was
reported.

Incident#
7424­
1
11
A
pesticide
incident
occurred
in
1998,
when
oxadiazon
was
sprayed
onto
landscaping
at
a
large
apartment
complex.
Several
individuals
reported
congestion,
sore
throat,
running
eyes,
and
hoarseness.
No
further
information
on
the
disposition
of
the
case
was
reported.

Incident#
8383­
1
A
pesticide
incident
occurred
in
1998,
when
a
man
used
oxadiazon
for
two
weeks
on
the
landscape
of
several
properties.
He
reported
hives
over
his
entire
body
area,
itching,
and
a
swollen
face.
He
experienced
a
rash
that
lasted
for
twenty­
four
hours.
However,
these
effects
only
occurred
on
the
last
two
days
of
use
and
may,
instead,
be
a
reaction
to
ibuprofen.
He
was
seen
by
a
physician.
No
further
information
on
the
disposition
of
the
case
was
reported.

Incident#
8383­
2
A
pesticide
incident
occurred
in
1997,
when
an
unknown
person
applied
the
product
to
grass
around
a
home.
A
year
and
a
half
later,
a
man
who
has
chronic
fatigue
syndrome,
reported
malaise.
He
now
lives
with
his
brother
and
reports
developing
acute
symptoms
whenever
he
returns
to
his
home.
No
further
information
on
the
disposition
of
the
case
was
reported.

Incident#
8476­
1
A
pesticide
incident
occurred
in
1999,
when
a
golf
course
was
treated.
Several
months
later,
a
female
employee
reported
respiratory
irritation
and
muscle
weakness.
No
further
information
on
the
disposition
of
the
case
was
reported.

Incident#
9413­
1
A
pesticide
incident
occurred
in
1999,
when
a
man
mixed
the
product
in
his
home
and
reported
a
seizure
the
next
morning.
Two
days
later
he
poured
the
chemical
into
a
spreader
and
ten
minutes
later
reported
a
seizure.
This
individual
has
a
history
of
ongoing
seizure
and
is
taking
medication
for
his
condition.
Physicians
treating
this
case
did
not
believe
that
the
seizure
were
related
to
the
pesticide
exposure.
No
further
information
on
the
disposition
of
the
case
was
reported.

Incident#
10179­
10
A
pesticide
incident
occurred
in
1996,
when
a
teacher
and
his
daughter
reported
headaches,
dizziness,
burning
eyes
and
skin,
coughing,
sore
throat
and
hoarseness
after
oxadiazon
was
applied
to
a
school
campus.
No
further
information
on
the
disposition
of
the
case
was
reported.
This
same
case
is
reported
in
the
California
data
summary.

No
consistent
pattern
of
ill
effects
was
seen
in
this
relatively
small
number
of
incidents.
There
was
some
evidence
of
irritative
and
allergic
effects
to
the
skin
and
respiratory
system.

II.
Poison
Control
Center
Data
­
1993
through
1998
Results
for
the
years
1993
through
1998
were
acquired
for
37
exposures
to
oxadiazon
reported
to
Poison
Control
Centers.
Cases
involving
exposures
to
multiple
products
are
12
excluded.
Only
4
cases
were
reported
among
children
under
six
years
of
age
and
six
cases
among
older
children
and
adults
exposed
at
their
workplace.
This
was
too
few
cases
to
warrant
detailed
analysis.
None
of
these
cases
reported
a
serious
outcome
and
only
one
of
the
occupational
cases
had
a
moderate
outcome.
There
were
27
non­
occupationally
exposed
cases
among
older
children
and
adults.

III.
California
Data
­
1982
through
1996
Detailed
descriptions
of
31
cases
submitted
to
the
California
Pesticide
Illness
Surveillance
Program
(
1982­
1996)
were
reviewed.
In
26
of
these
cases,
oxadiazon
was
used
alone
or
was
judged
to
be
responsible
for
the
health
effects.
Only
cases
with
a
definite,
probable
or
possible
relationship
were
reviewed.
Oxadiazon
ranked
84th
as
a
cause
of
systemic
poisoning
in
California
based
on
data
for
1982
through
1994.
Category
includes
cases
where
skin,
eye,
or
respiratory
effects
were
also
reported.

IV.
National
Pesticide
Telecommunications
Network
On
the
list
of
the
top
200
chemicals
for
which
NPTN
received
calls
from
1984­
1991
inclusively,
oxadiazon
was
ranked
192nd
with
12
incidents
in
humans
reported
and
5
incidents
in
animals
(
mostly
pets).

2.0
OCCUPATIONAL
EXPOSURES
2.1
Handler
Exposures
&
Assumptions
iii.
Handler
Exposure
Scenarios
Exposure
scenarios
can
be
thought
of
as
ways
of
categorizing
the
kinds
of
exposures
that
occur
related
to
the
use
of
a
chemical.
The
use
of
scenarios
as
a
basis
for
the
exposure
assessment
is
described
in
the
U.
S.
EPA
Guidelines
For
Exposure
Assessment
(
U.
S.
EPA;
Federal
Register
Volume
57,
Number
104;
May
29,
1992).

HED
uses
the
term
"
Handlers"
to
describe
those
individuals
who
are
involved
in
the
pesticide
application
process.
HED
believes
that
there
are
distinct
job
functions
or
tasks
related
to
applications
and
that
exposures
can
vary
depending
on
the
specifics
of
each
task.
Job
requirements
(
e.
g.,
amount
of
chemical
to
be
used
in
an
application),
the
kinds
of
equipment
used,
the
crop
or
target
being
treated,
and
the
circumstances
of
the
user
(
e.
g.,
the
level
of
protection
used
by
an
applicator)
can
cause
exposure
levels
to
differ
in
a
manner
specific
to
each
scenario.

HED
has
developed
a
series
of
general
descriptions
for
tasks
that
are
associated
with
pesticide
applications.
Tasks
associated
with
pesticide
use
(
i.
e.,
for
"
handlers")
can
generally
be
categorized
using
one
of
the
following
terms:
13

Occupational
Mixer/
loaders:
these
individuals
perform
tasks
in
preparation
for
an
application.
For
example,
they
would
prepare
dilute
spray
solutions
and/
or
load/
transfer
solid
materials
(
e.
g.,
granulars)
or
dilute
spray
solutions
into
application
equipment
such
as
a
groundboom
tractor
or
planter
prior
to
application.


Occupational
Applicators:
these
individuals
operate
application
equipment
during
the
application
of
oxadiazon
to
registered
sites.
These
individuals
can
make
applications
using
equipment
such
as
groundboom
sprayers
or
tractor­
drawn
spreaders
for
granular
materials.


Occupational
Mixer/
loader/
applicators:
these
individuals
are
involved
in
the
entire
pesticide
application
process
(
i.
e.,
they
do
all
job
functions
related
to
a
pesticide
application
event).
These
individuals
would
prepare
a
dilute
spray
solution
and
then
also
apply
the
solution.
HED
always
considers
some
exposures
to
be
mixer/
loader/
applicator
exposures
because
of
the
equipment
used
and
the
logistics
associated
with
such
applications.
For
example,
if
one
uses
a
small
handheld
device
such
as
a
1
gallon
low
pressure
handwand
sprayer
it
is
anticipated
that
one
individual
will
mix
a
spray
solution
and
then
apply
the
solution
because
of
labor
and
logistical
considerations.

HED
has
determined
that
there
are
potential
exposures
to
mixers,
loaders,
applicators,
or
other
handlers
during
usual
use­
patterns
associated
with
oxadiazon.
Based
on
the
use
patterns
and
potential
exposures
described
above,
14
major
exposure
scenarios
are
identified
in
this
document
to
represent
the
extent
of
oxadiazon
uses.
These
scenarios
include:
mixing/
loading
wettable
powders
for
chemigation
application
(
1a),
mixing/
loading
wettable
powders
for
groundboom
application
(
1b),
mixing/
loading
wettable
powders
for
rights­
of­
way
sprayer
(
1c),
loading
granular
formulations
(
2),
applying
with
a
groundboom
(
3),
applying
with
a
rights­
of­
way
sprayer
(
4),
applying
wettable­
powders
for
handgun
applicators
(
ORETF)
(
5),
applying
granular
with
a
tractor
drawn
spreader
(
6),
backpack
sprayer
(
LCO)
(
7),
low
pressure
handwand­­
wettable
powder
formulations
(
LCO)
(
8),
high
pressure
handwand
­­
(
wettable
powder
formulations)
(
9),
lawn
handgun
(
wettable
powder
formulations)
(
ORETF)
(
10),
granulars
with
a
push
type
spreader
(
ORETF)
(
11),
granulars
with
a
bellygrinder
(
LCO)
(
12).

In
most
cases,
HED
assesses
the
exposure
and
risk
to
mixer/
loaders
and
applicators
separately
for
tractor
drawn
applications
(
i.
e.
granular
spreaders)
in
the
RED
chapter.
This
practice
has
evolved,
not
because
it
is
believed
that
there
are
always
separate
job
functions,
but
rather
because
of
the
limited
amount
of
information
regarding
these
practices
along
with
limited
exposure
data.
For
occupational
RED
chapters
process,
HED
has
adopted
a
methodology
to
present
the
risks
separately
for
some
scenarios
and
combine
others.
Most
of
the
hand­
held
equipment
such
as
backpack
sprayers,
and
push
type
granular
spreaders
are
assessed
as
a
combined
function.
With
these
types
of
small
operations
the
mixing,
loading,
and
applying
are
almost
always
carried
out
by
the
same
individual
and
there
are
data
available
to
estimate
exposure
from
these
activities.
14
For
equipment
such
as
groundboom
tractors,
the
applications
is
assessed
separately
from
the
individual
who
mixes
and
loads
the
formulated
product.
By
separating
the
two
job
functions,
HED
can
determine
the
most
appropriate
PPE
or
engineering
control
without
requiring
the
handler
to
wear
PPE
throughout
the
entire
workday
or
engineering
controls
that
are
not
needed.

2.1.1
Summary
of
Occupational
Handler
Exposures
Table
4
presents
the
exposure
scenarios,
application
rates,
and
area
(
i.
e.,
acres
)
potentially
treated
that
have
been
used
in
the
exposure
calculations.
Oxadiazon
labels
include
a
multitude
of
uses
and
a
range
of
application
rates.

Chemical­
specific
data
for
assessing
human
exposures
during
pesticide
handling
activities
were
not
submitted
to
the
Agency
in
support
of
the
reregistration
of
oxadiazon.
Consequently
it
is
the
policy
of
the
HED
to
use
data
from
the
Pesticide
Handlers
Exposure
Database
(
PHED)
4
Version
1.1
to
assess
handler
exposures
for
regulatory
actions
when
chemical­
specific
monitoring
data
are
not
available.

PHED
was
designed
by
a
task
force
of
representatives
from
the
U.
S.
EPA,
Health
Canada,
the
California
Department
of
Pesticide
regulation,
and
member
companies
of
the
American
Crop
Protection
Association.
PHED
is
a
software
system
consisting
of
two
parts
­­
a
database
of
measured
exposure
values
for
workers
involved
in
the
handling
of
pesticides
under
actual
field
conditions
and
a
set
of
computer
algorithms
used
to
subset
and
statistically
summarize
the
selected
data.
Currently,
the
database
contains
values
for
over
1,700
monitored
individuals
(
i.
e.,
replicates)

Users
select
criteria
to
subset
the
PHED
database
to
reflect
the
exposure
scenario
being
evaluated.
The
subsetting
algorithms
in
PHED
are
based
on
the
central
assumption
that
the
magnitude
of
handler
exposures
to
pesticides
are
primarily
a
function
of
activity
(
e.
g.,
mixing/
loading,
applying),
formulation
type
(
e.
g.,
wettable
powders,
granulars),
application
method
(
e.
g.,
groundboom),
and
clothing
scenarios
(
e.
g.,
gloves,
double
layer
clothing).

Once
the
data
for
a
given
exposure
scenario
have
been
selected,
the
data
are
normalized
(
i.
e.,
divided
by)
by
the
amount
of
pesticide
handled
resulting
in
standard
unit
exposures
(
milligrams
of
exposure
per
pound
of
active
ingredient
handled).
Following
normalization,
the
data
are
statistically
summarized.
The
distribution
of
exposure
values
for
each
body
part
(
e.
g.,
chest
upper
arm)
is
categorized
as
normal,
lognormal,
or
"
other"
(
i.
e.,
neither
normal
nor
lognormal).
A
central
tendency
value
is
then
selected
from
the
distribution
of
the
exposure
values
for
each
body
part.
These
values
are
the
arithmetic
mean
for
normal
distributions,
the
geometric
mean
for
lognormal
distributions,
and
the
median
for
all
"
other"
distributions.
Once
selected,
the
central
tendency
values
for
each
body
part
are
composited
into
a
"
best
fit"
exposure
value
representing
the
entire
body.

The
unit
exposure
values
calculated
by
PHED
generally
range
from
the
geometric
mean
to
15
the
median
of
the
selected
data
set.
To
add
consistency
and
quality
control
to
the
values
produced
from
this
system,
the
PHED
Task
Force
has
evaluated
all
data
within
the
system
and
has
developed
a
set
of
grading
criteria
to
characterize
the
quality
of
the
original
study
data.
The
assessment
of
data
quality
is
based
on
the
number
of
observations
and
the
available
quality
control
data.
These
evaluation
criteria
and
the
caveats
specific
to
each
exposure
scenario
are
summarized
in
TableA4.
While
data
from
PHED
provide
the
best
available
information
on
handler
exposures,
it
should
be
noted
that
some
aspects
of
the
included
studies
(
e.
g.,
duration,
acres
treated,
pounds
of
active
ingredient
handled)
may
not
accurately
represent
labeled
uses
in
all
cases.
HED
has
developed
a
series
of
tables
of
standard
unit
exposure
values
for
many
occupational
scenarios
that
can
be
utilized
to
ensure
consistency
in
exposure
assessments.

The
method
of
risk
assessment
for
adult
non­
occupational/
residential
handlers
was
essentially
the
same
as
that
for
occupational
workers
with
similar
application
methods.
The
Residential
SOPs
(
1997)
and
the
Outdoor
Residential
Exposure
Task
Force
(
ORETF
)
study
data
were
both
used
to
estimate
exposure
and
compared.
After
preliminary
review
by
the
Agency,
the
ORETF
data
was
found
to
be
equal
or
superior
in
quality
to
the
data
set
from
the
Standard
Operating
Procedures
(
SOPs)
for
Residential
Exposure
Assessments
(
revised
December
1999)
currently
used
by
the
Agency.
Some
of
these
data
may
be
combined,
but
they
are
used
separately
for
this
assessment.

Table
4:
Exposure
Variables
for
Uses
ofOxadiazon
Exposure
Scenario
(
Scenario
#)
Crop
Type
Application
Rates
(
lb
ai/
acre)
a
Daily
Acres
Treatedb
Mixer/
Loader
Exposure
Mixing/
Loading
Wettable
Powders
for
Chemigation
Application
(
1a)
sod
farms
3
350
Mixing/
Loading
Wettable
Powders
for
Groundboom
Application
(
1b)
conifer
nurseries,
woody
ornamentals
4
40
herbaceous
ornamentals
3
40
sod
farms
3
80
golf
courses
4
40
Mixing/
Loading
Wettable
Powders
for
Rights­
of­
Way
Sprayer
(
1c)
roadside
turf,
ornamentals
4
40
Loading
Granular
formulations
(
2)
sod
farms,
conifers
forest.
4
80
golf
course
turf,
parks,
recreational
areas
4
40
woody
ornamentals
4
40
Applicator
Table
4:
Exposure
Variables
for
Uses
ofOxadiazon
Exposure
Scenario
(
Scenario
#)
Crop
Type
Application
Rates
(
lb
ai/
acre)
a
Daily
Acres
Treatedb
16
Applying
with
a
Groundboom
(
3)
sod
farms
3
80
herbaceous
ornamentals
3
40
golf
courses
4
40
conifer
nurseries,
woody
ornamentals
4
40
Applying
with
a
Rights­
of­
Way
Sprayer
(
4)
roadsides
4
40
Applying
Wettable­
Powders
for
Handgun
Applicators
(
ORETF)
(
5)
lawns,
parks,
recreational
areas
4
5
Applying
Granular
with
a
Tractor
Drawn
Spreader
(
6)
sod
farms
4
80
golf
courses
4
40
Mixer/
Loader/
Applicator
Backpack
Sprayer
(
LCO)
(
7)
l
a
w
n
s
,
g
o
l
f
c
o
u
r
s
e
s
,
ornamentals
nurseries
4
5
Low
Pressure
Handwand
­
Wettable
Powder
Formulations
(
LCO)
(
8)
lawns,
golf
courses,
nursery
stock
4
5
High
Pressure
Handwand
­­
(
Wettable
Powder
Formulations)
(
9)
woody
ornamentals,
conifer
nurseries.
4
5
Lawn
Handgun
(
Wettable
Powder
Formulations)
(
ORETF)
(
10)
ornamentals,
lawns,
parks
rec
areas
4
5
Granulars
with
a
Push
Type
Spreader
(
ORETF)
(
11)
lawns,
golf
courses,
parks,
r
e
c
r
e
a
t
i
o
n
a
l
a
r
e
a
s
,
ornamentals
4
5
Granulars
with
a
Bellygrinder
(
LCO)
(
12)
golf
courses,
parks,
rec
areas.
4
1
a
Application
rates
are
the
maximum
or
range
found
on
oxadiazon
labels
b
Daily
acres
treated
are
based
on
HED's
estimates
of
acreage
that
would
be
reasonably
expected
to
be
treated
in
a
single
day
for
each
exposure
scenario
of
concern.
LCO
=
lawn
care
operators
2.1.2
Summary
of
Uncertainties
The
handler
exposure
assessments
encompass
all
of
the
major
uses
of
oxadiazon
throughout
the
country.
It
is
difficult
to
assess
all
of
the
"
typical"
uses
(
i.
e.,
actual
or
predominate
application
rates
and
farm
sizes),
and
therefore,
an
assessment
has
been
developed
that
is
believed
to
be
realistic
and
yet
provides
a
reasonable
certainty
that
the
exposures
are
not
underestimated.
17
Daily
Dermal
Exposure
mg
ai
Day

Dermal
Unit
Exposure
mg
ai
lb
ai

Max.
Appl.
Rate
lb
ai
Acre

Max.
Area
Treated
Acres
Day
Daily
Inhalation
Exposure
mg
ai
day

Unit
Exposure

g
ai
lb
ai
x
Conversion
Factor
1mg
1,000

g
x
Use
Rate
lb
ai
A
x
Daily
Acres
Treated
A
day
The
assumptions
and
uncertainties
are
identified
below
to
be
used
in
risk
management
decisions:


Application
Rates:
The
application
rates
are
the
maximum
allowable
that
were
identified
on
the
available
product
labels.


Amount
Handled:
The
daily
acres
treated
are
HED
standard
values
(
see
Table
4).
The
values
for
groundboom
applications
in
agriculture
and
on
turf/
ornamentals
vary.
Groundboom
applications
in
an
agricultural
setting
are
based
on
an
80
acre
day
because
the
Agency
believes
it
would
take
8
hours
to
complete
that
type
of
application
with
common
equipment
and
that
acreage
estimate
for
various
crops
is
reasonable.
On
the
other
hand,
the
value
for
groundboom
applications
on
golfcourse
turf
is
based
on
treating
40
acres
because
that
is
the
value
calculated
to
represent
a
18
hole
course
(
they
account
for
about
10%
of
all
golf
courses
based
on
registrants
comments
and
investigation
by
Agency
personnel).
The
40
acre
value
is
not
the
maximum
that
can
be
treated
on
a
single
day
given
that
the
application
equipment
is
likely
capable
of
treating
higher
acreage.
The
daily
limitation
of
40
acres
per
day
is
based
on
the
fact
that
an
applicator
would
only
treat
a
course
a
single
time
on
any
given
day.

2.1.3
Calculations
of
Exposure
Potential
daily
dermal
exposure
is
calculated
using
the
following
formula:

Potential
daily
inhalation
exposure
is
calculated
using
the
following
formula:

These
calculations
of
potential
daily
exposure
to
oxadiazon
by
handlers
are
used
to
calculate
the
absorbed
doses
and
total
risk
to
those
handlers
(
see
Occupational
Risk
section).

2.1.4
Calculation
of
Cancer
Cancer
risk
assessments
for
handler
used
baseline
exposure
scenarios
and,
as
needed,
increasing
levels
of
risk
mitigation
(
PPE
and
engineering
controls)
to
achieve
cancer
risks
that
are
not
of
concern.
Tables
B1
to
B4
in
Appendix
B
present
total
cancer
risk
calculations
at
baseline,
with
various
PPE
(
ie.,
single
layer+
gloves
and
no
respirator,
double
layer
+
gloves
and
no
18
Daily
Dermal
Exposure
mg
ai
day

Unit
Exposure
mg
ai
lb
ai
x
Use
Rate
lb
ai
A
x
Daily
Acres
Treated
A
day
Daily
Inhalation
Exposure
mg
ai
day

Unit
Exposure

g
ai
lb
ai
x
Conversion
Factor
1mg
1,000

g
x
Use
Rate
lb
ai
A
x
Daily
Acres
Treated
A
day
Daily
Inhalation
Dose
mg
ai
kg/
day

Daily
Inhalation
Exposure
mg
ai
day
x
1
Body
Weight
(
kg)

Daily
Dermal
Dose
mg
ai
Kg/
Day

Daily
Dermal
Exposure
mg
ai
Day
x
1
Body
Weight
(
Kg)
x
0.09
Dermal
Absorption
Factor
Total
Daily
Dose

Daily
Dermal
Dose
mg
kg/
day

Daily
Inhalation
Dose
mg
kg/
day
LADD
mg
kg/
day

Daily
Total
Dose
mg
kg/
day
x
days
worked
365
days
per
year
x
35
years
worked
70
year
lifetime
respirator,
single
layer+
gloves
and
respirator
and
double
layer
+
gloves
and
respirator)
and
with
engineering
controls,
respectively,
for
each
exposure
scenario.

The
calculations
of
daily
dermal
and
inhalation
exposure
to
oxadiazon
by
handlers
were
used
to
calculate
the
daily
dose,
and
hence
the
risks,
to
those
handlers.
Potential
daily
dermal
exposure
was
calculated
using
the
following
formula:

Potential
daily
inhalation
exposure
was
calculated
using
the
following
formula:

The
daily
dermal
and
inhalation
doses
were
calculated
using
a
70
kg
body
weight
using
the
following
formulas:

The
lifetime
average
daily
dose
(
LADD)
was
calculated
using
the
following
formula:

T
otal
cancer
risk
was
calculated
using
the
following
formula:
19
Total
Cancer
Risk

LADD
x
Q1

where
Q
1
*
=
7.11x10­
2
(
mg/
kg/
day)­
1
The
following
assumptions
and
factors
were
used
in
order
to
complete
this
cancer
risk
assessment:


The
average
body
weight
of
70
kg
is
used,
representing
a
typical
adult.


Career
duration
is
assumed
to
be
35
years.
This
represents
a
typical
working
lifetime.


Lifetime
is
assumed
to
be
70
years.


Dermal
absorption
is
assumed
to
be
9
%,
and
inhalation
absorption
is
assumed
to
be
100
percent
of
the
oral
dose.
The
dermal
and
inhalation
doses
were
added
together
to
represent
total
daily
dose.


The
Q1*
used
in
the
cancer
assessment
was
7.11x10­
2(
mg/
kg/
day)­
1
.


Two
exposure
frequencies
were
used
in
the
calculations,
the
first
represented
the
maximum
number
of
applications
per
site
per
season
to
represent
private
use
(
3),
and
the
second
frequency
applied
a
factor
of
ten
to
the
first
frequency
to
represent
commercial
handlers
making
multiple
applications
per
site
per
season
(
30).

The
Agency
has
defined
a
range
of
acceptable
cancer
risks
based
on
a
policy
memorandum
issued
in
1996
by
then
office
director,
Dan
Barolo.
This
memo
refers
to
a
predetermined
quantified
"
level
of
concern"
for
occupational
carcinogenic
risk.
In
summary,
this
policy
memo
indicates
occupational
carcinogenic
risks
that
are
1
x
10­
6
or
lower
require
no
risk
management
action.
For
those
chemicals
subject
to
reregistration,
the
Agency
is
to
carefully
examine
uses
with
estimated
risks
in
the
10­
6
to
10­
4
range
to
seek
ways
of
cost­
effectively
reducing
risks.
If
carcinogenic
risks
are
in
this
range
for
occupational
handlers,
increased
levels
of
personal
protection
would
be
warranted
as
is
commonly
applied
with
noncancer
risk
estimates
(
e.
g.,
additional
PPE
or
engineering
controls).
Carcinogenic
risks
that
remain
above
1.0
x
10­
4
at
the
highest
level
of
mitigation
appropriate
for
that
scenario
remain
a
concern.

2.2
Risk
From
Handler
Exposures
Using
the
daily
dermal
exposure
scenarios
identified
in
the
exposure
section,
EPA
calculated
the
potential
risk
to
persons
from
handler
exposures
and
post­
application
exposures
to
oxadiazon.
20
Daily
Inhalation
Dose
mg
ai
kg/
day

Daily
Inhalation
Exposure
mg
ai
day
x
1
Body
Weight
(
kg)

1
(
100%)

Daily
Dermal
Dose
mg
ai
kg/
Day

Daily
Dermal
Exposure
mg
ai
Day
x
1
Body
Weight
(
kg)

0.09
(
9%)

MOE

NOAEL
mg
kg/
day
Dermal
Daily
Dose
mg
kg/
day
MOE

NOAEL
mg
kg/
day
Inhlation
Daily
Dose
mg
kg/
day
Potential
dermal
and
inhalation
daily
exposures
for
occupational
handlers
were
calculated
using
the
following
formulas
(
9%
dermal
absorption
was
assumed):

The
daily
dermal
and
inhalation
doses
were
calculated
using
a
60
kg
body
weight
using
the
following
formulas:

The
MOEs
were
calculated
using
the
following
formulas:

A
total
MOE
is
also
calculated
because
there
is
a
common
endpoint.
The
uncertainty
factor
of
100
is
applied
to
all
routes
and
exposure
durations.
Route
specific
data
are
available
for
the
dermal
and
oral
routes,
and
therefore,
the
following
reciprocal
MOE
calculation
is
used:

1/((
1/
Dermal
MOE)
+
(
1/
Inhalation
MOE)

2.2.1
Risk
From
Handler
Exposures
Handler
exposure
assessments
are
completed
by
EPA
using
a
baseline
exposure
scenario
and,
if
required,
increasing
levels
of
risk
mitigation
(
PPE
and
engineering
controls)
to
achieve
a
margin
of
exposure
of
100
for
dermal
and
inhalation
exposure
or
cancer
risk
of
1.0x
10­
4
to
1.0x
10­
6.
Appendix
A
presents
the
short­
term
and
intermediate
term
MOE
calculations
for
baseline
exposure
plus
the
risk
mitigation
measures
of
personal
protective
equipment
(
PPE)
and
engineering
controls
using
data
from
PHED
and
ORTEF
for
the
uses
of
oxadiazon.
Aventis
is
a
member
of
the
ORETF
so
there
are
no
data
compensation
issues
associated
with
the
use
of
this
data.
Appendix
B
Tables
B1
to
B4
presents
the
cancer
risk
calculations
for
baseline
exposure
plus
the
risk
mitigation
measures
of
personal
protective
equipment
(
PPE)
and
engineering
21
controls.

EPA
calculated
the
baseline
MOE
(
short­
term
and
intermediate­
term)
and
cancer
for
each
of
the
exposure
scenarios
using
the
following
baseline
PPE
assumptions:

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

$
occupational
mixers
and
loaders
using
open
mixing
techniques
are
wearing
longsleeved
shirts,
long
pants,
and
no
gloves.

$
occupational
applicators
use
open
cab
tractor­
driven
application
equipment.

$
occupational
handlers
(
mixers,
loaders,
and
applicators)
who
use
hand­
held
application
equipment
are
wearing
long­
sleeve
shirts,
long
pants,
and
no
gloves.

If
the
baseline
short­
term
or
intermediate­
term
MOE
calculated
using
this
baseline
PPE
was
100
or
greater
(
since
the
NOAEL
is
based
on
data
from
animal
studies)
for
an
exposure
scenario,
then
no
further
calculations
were
made.
If
the
baseline
short­
term
or
intermediate­
term
MOE
was
less
than
100
for
any
exposure
scenario,
an
additional
short­
term
or
intermediate­
term
MOE
was
calculated
based
on
increasing
the
level
of
PPE
over
the
baseline
PPE.
HED
calculated
the
additional
PPE
short­
term
or
intermediate­
term
MOE
for
each
occupational
exposure
scenario
with
a
baseline
total
MOE
of
less
than
100,
using
the
following
additional
PPE
assumptions:

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

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

If
the
additional­
PPE
short­
term
or
intermediate­
term
MOE
calculated
using
this
additional­
PPE
was
100
or
greater
(
the
NOAEL
is
based
on
data
from
animal
studies)
for
an
exposure
scenario,
then
no
further
calculations
were
made.
If
the
additional­
PPE
short­
term
or
intermediate­
term
MOE
remained
less
than
100
for
any
occupational
exposure
scenario,
an
addition
short­
term
or
intermediate­
term
MOE
was
calculated
based
on
mandatory
use
of
engineering
controls
where
feasible.
Engineering
controls
are
not
available
for
occupational
handlers
(
mixers,
loaders,
and
applicators)
who
use
hand­
held
application
equipment.
HED
calculated
the
engineering­
control
short­
term
or
intermediate­
term
MOE
for
each
occupational
exposure
scenario
with
an
additional­
PPE
short­
term
or
intermediate­
term
MOE
of
less
than
100,
using
the
following
engineering
control
assumptions:

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

$
occupational
mixers
and
loaders
handling
liquid
formulations
using
a
closed
system
22
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.

2.2.2
Summary
of
Handler
MOEs
and
Cancer
Table
5
summarizes
the
numeric
MOE
values
for
both
the
short­
and
intermediate­
term
exposure
durations.
The
MOEs
are
presented
for
baseline,
PPE
and
engineering
controls.
Cancer
values
also
summarized
in
Table
6
at
different
levels
of
mitigation.
Baseline
for
non­
cancer
assessment
represents
long
pants,
long
sleeved
shirts
and
no
gloves
or
respirator,
PPE
dermal
unit
exposure
represents
long
pants,
long
shirts
and
gloves
for
scenarios
5,
7,
9
and
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.

The
results
of
the
short
and
intermediate­
term
handler
assessments
indicate
that
all
potential
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).
In
the
majority
of
cases,
it
is
dermal
exposure
rather
than
the
inhalation
exposure
driving
the
total
MOEs.
In
total,
37
MOEs
were
calculated
for
the
various
application
rates.
The
total
MOEs
for
all
the
scenarios
range
from
2
to
3000.

The
results
of
the
Cancer
Risk
indicate
that
the
values
range
from
1.65E­
2
to
4.66E­
7
at
the
baseline
(
long
pants,
long
shirts
and
no
gloves),
2.56E­
3
to
4.11E­
7
at
PPE1
(
long
pants,
long
shirts,
gloves
and
no
respirator),
2.40E­
3
at
PPE2
(
long
pants,
long
shirts,
double
layer,
gloves
and
no
respirator),
1.05E­
3
to
1.98E­
7
at
PPE3
(
long
pants,
long
shirts,
gloves
and
respirator),
8.90E­
4
to
1.38E­
07
at
PPE4
(
long
pants,
long
shirts,
double
layer,
gloves
and
respirator)
and
9.92E­
5
to
1.10E­
8
at
engineering
control.

Table
5:
Exposure
Variables,
MOEs
for
Uses
of
Oxadiazon
Exposure
Scenario
(
Scenario
#)
Crop
Type
App
Rates
(
lb
ai/
acre)
Daily
Acres
Treated
Dermal
MOEs
Inhalation
MOEs
Base
line
PPE
Eng.
Control
Base
line
PPE
En
Con
Mixer/
Loader
Table
5:
Exposure
Variables,
MOEs
for
Uses
of
Oxadiazon
Exposure
Scenario
(
Scenario
#)
Crop
Type
App
Rates
(
lb
ai/
acre)
Daily
Acres
Treated
Dermal
MOEs
Inhalation
MOEs
Total
MOEs
Base
line
PPE
Eng.
Control
Base
line
PPE
Eng.
Control
Base
line
PPE
Eng.
Control
23
Mixing/
Loading
Wettable
Powders
for
Chemigation
Application
(
1a)
sod
farms
3
350
2
59
gl,
dl
780
wsp
16
80
resp
2900
2
35
610
Mixing/
Loading
Wettable
Powders
for
Groundboom
Application
(
1b)
conifer
nurseries,
woody
ornamentals
4
40
14
380
gl,
dl
NA
100
520
resp
NA
12
220
NA
herbaceous
ornamentals
3
40
18
510
gl,
dl
NA
140
700
resp
NA
16
300
NA
sod
farms
3
80
9
260
gl,
dl
NA
70
350
resp
NA
8
150
NA
golf
courses
4
40
14
380
gl,
dl
NA
100
520
resp
NA
12
220
NA
Mixing/
Loading
Wettable
Powders
for
Rights­
of­
Way
Sprayer
(
1c)
r
o
a
d
s
i
d
e
t
u
r
f
,

ornamentals
4
40
14
380
gl,
dl
NA
100
520
resp
NA
12
220
NA
Loading
Granular
formulations
(
2)
so
d
f
a
rms
,
coni
fer
s
forest
4
80
3000
NA
NA
1300
NA
NA
920
NA
NA
golf
course
turf,
parks,

recreational
areas
4
40
6000
NA
NA
2600
NA
NA
1800
NA
NA
woody
ornamentals
4
40
6000
NA
NA
2600
NA
NA
1800
NA
NA
Applicator
Applying
with
a
Groundboom
(
3)
sod
farms
3
80
2400
NA
NA
4100
NA
NA
1500
NA
NA
herbaceous
ornamentals
3
40
4800
NA
NA
8100
NA
NA
3000
NA
NA
golf
courses
40
3600
NA
NA
6100
NA
NA
2300
NA
NA
conifer
nurseries,
woody
ornamentals
4
40
3600
NA
NA
6100
NA
NA
2300
NA
NA
Applying
with
a
Rights­
of­
Way
Sprayer
(
4)
roadsides
4
40
38
130
NA
1200
1200
NA
37
120
NA
Applying
Wettable­
Powders
for
Handgun
Applicators
(
ORETF)
(
5)
l
a
w
n
s
,
p
a
r
k
s
,

recreational
areas
4
5
See
PPE
550
gl
NA
36000
36000
NA
See
PPE
540
NA
Table
5:
Exposure
Variables,
MOEs
for
Uses
of
Oxadiazon
Exposure
Scenario
(
Scenario
#)
Crop
Type
App
Rates
(
lb
ai/
acre)
Daily
Acres
Treated
Dermal
MOEs
Inhalation
MOEs
Total
MOEs
Base
line
PPE
Eng.
Control
Base
line
PPE
Eng.
Control
Base
line
PPE
Eng.
Control
24
Applying
Granular
with
a
Tractor
Drawn
Spreader
(
6)
sod
farms
4
80
2500
NA
NA
1900
NA
NA
1100
NA
NA
golf
courses
4
40
5100
NA
NA
3800
NA
NA
2200
NA
NA
Mixer/
Loader/
Applicator
Backpack
Sprayer
(
LCO)
(
7)
l
awns,
gol
f
courses,

ornamentals
nurseries
4
5
See
PPE
160
gl
NA
1200
1200
NA
See
PPE
140
NA
Low
Pressure
Handwand
­

Wettable
Powder
Formulations
(
LCO)
(
8)
lawns,
golf
courses,

nursery
stock
4
5
14
65
gl,
dl
NF
33
160
resp
NF
10
46
NF
High
Pressure
Handwand
­­

(
Wettable
Powder
Formulations)

(
9)
woody
ornamentals,

conifer
nurseries.
4
5
See
PPE
160
gl
NA
300
300
NA
See
PPE
100
NA
Lawn
Handgun
(
Wettable
Powder
Formulations)
(
ORETF)
(
10)
ornamentals,
lawns,

parks
rec
areas
4
5
560
NA
NA
580
NA
NA
280
NA
NA
Granulars
with
a
Push
Type
Spreader
(
ORETF)
(
11)
lawns,
golf
courses,

parks,
recreational
areas,

ornamentals
4
5
1100
NA
NA
4800000
NA
NA
1100
NA
NA
Granulars
with
a
Bellygrinder
(
LCO)
(
12)
golf
courses,
parks,
rec
areas.
4
1
200
NA
NA
2900
NA
NA
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
scenarios5,
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
gl
=
gloves
dl
=
double
layer
wsp
=
water
soluble
packages
resp
=
dust
mist
respirator
25
Table
6:
Exposure
Variables,
Cancer
for
Uses
of
Oxadiazon
Exposure
Scenario
(
Scenario
#)
Crop/
Target
Appl
Rates
(
lb
ai/
acre)
Daily
Acres
Treated
Cancer
Base
line
PPE
1
PPE
2
PPE
3
PPE
4
Eng.
Control
Mixer/
Loader
Mixing/
Loading
Wettable
Powders
for
Chemigation
Application
(
1a)
sod
farms
3
350
1.65e­
03/

1.65e­
02
2.56e­
04/

2.56e­
03
2.40e­
04/

2.40e­
03
1.05e­
04/

1.05e­
03
8.90e­
05/

8.90e­
04
4.92e­
06/

4.92e­
05
Mixing/
Loading
Wettable
Powders
for
Groundboom
Application
(
1b)
conifer
nurseries,
woody
ornamentals
4
40
2.51e­
04/

2.51e­
03
3.89e­
05/

3.89e­
04
3.65e­
05/

3.65e­
04
1.60e­
05/

1.60e­
04
1.36e­
05/

1.36e­
04
7.49e­
07/

7.49e­
06
herbaceous
ornamentals
3
40
1.88e­
04/

1.88e­
03
2.92e­
05/

2.92e­
04
2.74e­
05/

2.74e­
04
1.20e­
05/

1.20e­
04
1.02e­
05/

1.02e­
04
5.62e­
07/

5.62e­
06
sod
farms
3
80
3.77e­
04/

3.77e­
03
5.84e­
05/

5.84e­
04
5.48e­
05/

5.48e­
04
2.39e­
05/

2.39e­
04
2.03e­
05/

2.03e­
04
1.12e­
06/

1.12e­
05
golf
courses
4
40
2.51e­
04/

2.51e­
03
3.89e­
05/

3.89e­
04
3.65e­
05/

3.65e­
04
1.60e­
05/

1.60e­
04
1.36e­
05/

1.36e­
04
7.49e­
07/

7.49e­
06
Mixing/
Loading
Wettable
Powders
for
Rights­
of­
Way
Sprayer
(
1c)
roadside
turf,
ornamentals
4
40
2.51e­
04/

2.51e­
03
3.89e­
05/

3.89e­
04
3.65e­
05/

3.65e­
04
1.60e­
05/

1.60e­
04
1.36e­
05/

1.36e­
04
7.49e­
07/

7.49e­
06
Loading
Granular
formulations
(
2)
sod
farms,
conifers
forest
4
80
3.28e­
06/

3.28e­
05
3.10e­
06/

3.10e­
05
2.68e­
06/

2.68e­
05
1.28e­
06/

1.28e­
05
8.63e­
07/

8.63e­
06
2.20e­
08/

2.20e­
07
golf
course
turf,
parks,

recreational
areas
4
40
1.64e­
06/

1.64e­
05
1.55e­
06/

1.55e­
05
1.34e­
06/

1.34e­
05
6.42e­
07/

6.42e­
06
4.31e­
07/

4.31e­
06
1.10e­
08/

1.10e­
07
woody
ornamentals
4
40
1.64e­
06/

1.64e­
05
1.55e­
06/

1.55e­
05
1.34e­
06/

1.34e­
05
6.42e­
07/

6.42e­
06
4.31e­
07/

4.31e­
06
3.29e­
08/

3.29e­
07
Applicator
Applying
with
a
Groundboom
(
3)
sod
farms
3
80
2.00e­
06/

2.00e­
05
2.00e­
06/

2.00e­
05
1.73e­
06/

1.73e­
05
1.41e­
06/

1.41e­
05
1.14e­
06/

1.14e­
05
4.94e­
07/

4.94e­
06
herbaceous
ornamentals
3
40
1.00e­
06/

1.00e­
05
1.00e­
06/

1.00e­
05
8.67e­
07/

8.67e­
06
7.06e­
07/

7.06e­
06
5.71e­
07/

5.71e­
06
2.47e­
07/

2.47e­
06
golf
courses
4
40
1.34e­
06/

1.34e­
05
1.34e­
06/

1.34e­
05
1.16e­
06/

1.16e­
05
9.42e­
07/

9.42e­
06
7.61e­
07/

7.61e­
06
3.29e­
07/

3.29e­
06
Table
6:
Exposure
Variables,
Cancer
for
Uses
of
Oxadiazon
Exposure
Scenario
(
Scenario
#)
Crop/
Target
Appl
Rates
(
lb
ai/
acre)
Daily
Acres
Treated
Cancer
Base
line
PPE
1
PPE
2
PPE
3
PPE
4
Eng.
Control
26
conifer
nurseries,
woody
ornamentals
4
40
1.34e­
06/

1.34e­
05
1.34e­
06/

1.34e­
05
1.16e­
06/

1.16e­
05
9.42e­
07/

9.42e­
06
7.61e­
07/

7.61e­
06
3.29e­
07/

3.29e­
06
Applying
with
a
Rights­
of­
Way
Sprayer
(
4)
roadsides
4
40
8.07e­
05/

8.07e­
04
2.60e­
05/

2.60e­
04
2.00e­
05/

2.00e­
04
2.40e­
05/

2.40e­
04
1.80e­
05/

1.80e­
04
NA
Applying
Wettable­
Powders
for
Handgun
Applicators
(
ORETF)
(
5)
lawns,
parks,
recreational
areas
4
5
See
PPE
5.57e­
06/

5.57e­
05
2.94e­
06/

2.94e­
05
5.50e­
06/

5.50e­
05
2.87e­
06/

2.87e­
05
NA
Applying
Granular
with
a
Tractor
Drawn
Spreader
(
6)
sod
farms
4
80
9.31e­
07/

9.31e­
06
8.23e­
07/

8.23e­
05
7.03e­
07/

7.03e­
06
3.95e­
07/

3.95e­
06
2.75e­
07/

2.75e­
06
1.82e­
07/

1.82e­
06
golf
courses
4
40
4.66e­
07/

4.66e­
06
4.11e­
07/

4.11e­
06
3.51e­
07/

3.51e­
06
1.98e­
07/

1.98e­
06
1.38e­
07/

1.38e­
06
9.11e­
08/

9.11e­
07
Mixer/
Loader/
Applicator
Backpack
Sprayer
(
LCO)
(
7)
l
a
w
n
s
,
g
o
l
f
c
o
u
r
s
e
s
,

ornamentals
nurseries
4
5
See
PPE
2.13e­
05/

2.13e­
04
1.45e­
05/

1.45e­
04
1.93e­
05/

1.93e­
04
1.25e­
05/

1.25e­
04
NA
Low
Pressure
Handwand
­
Wettable
Powder
Formulations
(
LCO)
(
8)
lawns,
golf
courses,
nursery
stock
4
5
3.10e­
04/

3.10e­
03
1.56e­
04/

1.56e­
03
1.38e­
04/

1.38e­
03
8.30e­
05/

8.30e­
04
6.50e­
05/

6.50e­
04
NA
High
Pressure
Handwand
­­
(
Wettable
Powder
Formulations)
(
9)
woody
ornamentals,
conifer
nurseries.
4
5
See
PPE
1.88e05/

1.88e­
04
1.20e­
05/

1.20e­
04
1.98e­
05/

1.98e­
04
1.31e­
05/

1.31e­
04
NA
Lawn
Handgun
(
Wettable
Powder
Formulations)
(
ORETF)
(
10)
ornamentals,
lawns,
parks
rec
areas
4
5
1.06e­
05/

1.06e­
04
1.06e­
05/

1.06e­
04
8.03e­
06/

8.03e­
05
6.44e­
06/

6.44e­
05
3.89e­
06/

3.89e­
05
NA
Granulars
with
a
Push
Type
Spreader
(
ORETF)
(
11)
lawns,
golf
courses,
parks,

recreational
areas,
ornamentals
4
5
2.33e­
06/

2.33e­
05
1.80e­
06/

1.80e­
05
No
data
1.80e­
06/

1.80e­
05
No
data
NA
Granulars
with
a
Bellygrinder
(
LCO)
(
12)
golf
courses,
parks,
rec
areas.
4
1
1.61e­
05/

1.61e­
04
1.50e­
05/

1.50e­
04
9.60e­
06/

9.60e­
05
1.42e­
05/

1.42e­
04
8.77e­
06/

8.77e­
05
NA
Baseline
dermal
unit
exposure
scenarios
includes
long
pants,
long
shirts
and
no
gloves.

PPE
1
cancer
risk
includes
long
pants,
long
shirts,
gloves
and
no
respirator.

PPE
2
cancer
risk
includes
long
pants,
long
shirts,
double
layer,
gloves
and
no
respirator.

PPE
3
cancer
risk
includes
long
pants,
long
shirts,
gloves
and
respirator.

PPE
4
cancer
risk
includes
long
pants,
long
shirts,
double
layer,
gloves
and
respirator.

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

Engineering
inhalation
unit
exposure
represents
no
respirator.
27
Two
exposure
frequencies
were
used
for
cancer,
the
first
represented
the
maximum
number
of
applications
per
site
per
season
to
represent
private
use
(
3),
and
the
second
frequency
applied
a
factor
of
ten
to
the
first
frequency
to
represent
commercial
handlers
making
multiple
applications
per
site
per
season
(
30).
NA=
Not
applicable
3.0
POSTAPPLICATION
EXPOSURES
3.1
Postapplication
Exposure
&
Assumption
HED
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
in
agriculture
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
postapplication
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
turfgrass:
mowing
3.1.1
Data
Source
and
Assumptions
for
Scenario
Considered
Although
two
transferable
turf
residues
(
TTR)
studies
(
MRID#
449955­
01and
449955­
02)
and
one
Jazzercize
study
(
MRID#
435178­
01)
were
submitted
in
support
of
the
reregistration
of
oxadiazon,
only
the
Jazzercize
study
found
to
be
acceptable
for
this
assessment.
The
TTR
studies
were
reviewed
and
found
to
have
TTR
transfer
efficiencies
of
less
than1%
(
transfer
efficiency
=
%
of
the
application
rate).
TTR
data
generated
by
ORETF
members
rely
on
a
modified
version
of
the
California
roller
(
ORETF
roller)
that
appears
to
have
a
much
lower
transfer
efficiency
(
percent
of
application
rate)
than
the
original
version.
Many
TTR
data
submitted
by
ORETF
members
show
percent
transferabilities
of
less
than
1%
of
the
application
rate
for
sprayable
formulations
and
less
than
0.5%
of
the
application
rate
for
granular
formulations.
ORD
has
conducted
a
round
robin
test
of
TTR
methods
that
included
the
ORETF
roller
(
Fortune
1997).
While
ORD
concluded
that
the
ORETF
roller
performed
the
best
of
all
methods,
transfer
efficiency
for
three
liquid
herbicide
formulations
indicated
a
transfer
efficiency
of
~
0.5%.
The
ORETF
data
was
not
used
with
the
revised
Transfer
Coefficients
referenced
in
current
residential
SOP
since
these
revised
TCs
are
based
on
TTR
transfer
efficiencies
of
~
1­
5%
(
transfer
efficiency
=
%
of
the
application
rate).
Therefore
the
TTR
values
from
these
studies
are
not
included
in
this
assessment.
The
Jazzercize
study
(
MRID
#
435178­
01)
was
reviewed
and
found
to
be
acceptable
for
this
assessment.

MRID
435178­
01.
Evaluation
of
Turf
Re­
entry
Exposure
to
a
Broadcast
Application
of
Ronstar
®
50
WP,
L.
Rosenheck
(
1995).
Pan­
Agricultural
Labs,
Inc.
Number:
93293
Unpublished
study
prepared
by
Rhone
Poulenc
AG
Company.
300
pages.
28
This
study
on
turf­
transferable
residues
(
TTR)
was
submitted
by
Rhone
Poulenc
Ag
Company,
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:

a)
Application
at
the
maximum
label
rate
followed
by
re­
entry
as
soon
as
the
turf
was
dry.
b)
Application
within
30
minuted
by
sprinkler
irrigation
of
1/
10
inch
of
water
with
re­
entry
occurring
as
soon
as
the
turf
is
dry.

Overall,
the
study
met
most
criteria
of
the
OPPTS
Post­
application
Exposure
Monitoring
Test
Guidelines,
875.2100,
Transferable
Residue
Dissipation:
Lawn
and
Turf.

Most
of
the
field
samples
returned
results
that
were
<
LOQ
for
oxadiazon,.
No
LOD
value
was
defined
in
the
study,
however.
The
overall
mean
recovery
for
field
fortification
samples
of
oxadiazon
ranged
between
64.7
to
99.6%.
On
Day
0,
the
highest
average
turf­
transferable
residues
(
TTR)
for
non­
irrigated
plot
was
1.22
µ
g
per
cm
2
and
0.694
µ
g
per
cm
2
on
irrigated
plot.
The
TTR
values
adjusted
for
an
application
rate
of
4.0
lb
ai/
A.

The
TTR
value
from
the
above
study
utilized
a
wettable
powder
formulation
which
by
far
has
a
higher
potential
for
exposure
than
the
oxadiazon
granular
formulations.
Since
91%
of
the
total
use
involves
granular
formulations,
using
wettable
powder
TTR
values
is
a
conservative
approach
and
can
be
considered
the
upper
level
estimates
of
exposure.

A
linear
regression
to
calculate
a
dissipation
rate
(
T
½
)
for
oxadiazon
TTR
from
irrigated
and
non­
irrigated
test
sites
was
performed,
using
all
non­
zero,
uncorrected,
averaged
data
point
from
DAT­
0
through
DAT­
7.
Calculated
dissipation
half­
lives
for
the
irrigated
plot
was
1.7days
(
R2=
0.64)
and
for
the
non­
irrigated
plot
was
1.4
days
(
R2=
0.64)

3.1.2
Assumptions
Used
in
Postapplication
Exposure
Calculations
Based
on
data
submitted
for
reregistration,
the
most
common
postapplication
exposures
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
postapplication
activity
after
either
spraying
method.
Treated
turf
or
grasses
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
postapplication
exposure
is
anticipated
to
be
negligible.
Therefore,
all
calculations
of
postapplication
risk
estimates
have
been
done
for
dermal
exposure
only.
Postapplication
exposure
via
the
inhalation
route
is
considered
to
be
negligible.
29
Dose
(
mg/
kg/
d)

(
DFR
(

g/
cm
2)
x
Tc
(
cm
2/
hr)
x
CF
1
mg
1,000

g
x
Abs
x
ED
(
hrs/
day))

BW
MOE

NOAEL
(
mg/
kg/
day)
Dose
(
mg/
kg/
day)
3.1.3
Exposure
and
Risk
Calculations
Short­
and
intermediate­
term
daily
absorbed
doses
and
MOEs
were
calculated
as
follows:

Where:
DFR
=
daily
DFR,
as
calculated
above
for
the
assumed
average
reentry
day
Tc
=
transfer
coefficient;
CF
=
conversion
factor
(
i.
e.,
1
mg/
1,000

g)
Abs
=
dermal
absorption
(
9%)
ED
=
exposure
duration;
8
hours
worked
per
day
BW
=
body
weight
(
60
kg)

Dermal
MOEs
were
calculated
as
follows:

Where:
NOAEL
=
12
mg/
kg/
day
for
short­
term
and
intermediate­
term
Dose
=
calculated
absorbed
dermal
dose
For
the
purposes
of
occupational
risk
assessments,
the
following
residue
values
were
chosen:

°
For
short­
term
and
intermediate­
term
postapplication
turf
activities,
the
Residential
SOP
standard
5%
of
the
amount
ai
applied
is
used,
along
with
standard
transfer
coefficients
(
updated
8/
2000).

3.1.4
Postapplication
Exposure
Risk
Estimates
For
turf
or
sod
mowing
and
harvesting,
transfer
coefficients
of
500
and
16,500
cm2/
hr
were
used,
based
on
the
ARTF
data
(
see
HED
Exposure
SAC
Policy
guidance
3.1,
8/
00).
As
shown
in
Table
C1,
short
and
intermediate
­
term
exposure
had
an
estimated
MOEs
of
30­
1,000.
Similarly
occupational
post
application
cancer
risks
were
estimated
to
fall
within
the
acceptable
range
of
1
x
10­
4
to
1
x
10­
6.
Residential
SOP
standard
value
of
5%
of
application
rate
used.(
see
Appendix
C,
Table
C1)

3.2
Non­
Occupational
Postapplication
Exposures
and
Risk
Estimates
30
The
Agency
has
determined
that
there
are
potential
postapplication
exposures
to
residents
entering
oxadiazon
treated
lawns,
either
as
a
result
of
commercial
or
private
application.

3.2.1
Postapplication
Exposure
Scenarios
The
scenarios
likely
to
result
in
postapplication
exposures
are
presented
below.
The
duration
of
postapplication
dermal
exposure
is
expected
to
be
either
short­
term
or
intermediate­
term,
based
on
oxadiazon
turf
residue
dissipation
data.
As
calculated
from
the
previously
discussed
Jazzercise
study
(
MRID
#
435178­
01),
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.
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
be
more
like
random
intermittent
events
of
varying
doses,
all
less
than
the
dose
predicted
in
this
assessment.
The
resulting
risk
estimates
are
summarized
in
Tables
C2
(
non­
cancer)
and
C3
(
cancer).
Residential
postapplication
exposure
assessments
assumed
residents
wear
the
following
attire:
short
sleeved
shirt,
short
pants,
shoes
and
socks,
and
no
gloves
or
respirator.
As
stated
in
the
occupational
postapplication
risk
section
of
this
document,
negligible
oxadiazon
inhalation
exposure
is
anticipated
for
non­
handlers,
due
to
low
chemical
vapor
pressure
and
dilution
of
vapor
outdoors.
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:

(
1)
Adults
involved
in
a
low
exposure
activity,
such
as
golfing
or
walking
on
treated
turf.
(
2)
Toddlers
involved
in
a
low
exposure
activity,
such
as
walking
on
treated
turf.
(
3)
Adults
mowing
or
other
moderate
contact
activity,
for
1­
2
hours.
(
4)
Adults
involved
in
a
high
exposure
activity,
such
as
heavy
yard
work
(
doses
similar
to
occupational
scenarios
for
cutting
and
harvesting
sod).
(
5)
Toddlers
involved
in
high
exposure
activities
on
turf.

3.2.2
Data
Sources
for
Scenarios
Considered
A
turf
re­
entry
exposure
study
(
Jazzercise
study),
using
a
spray
application,
was
described
in
the
Occupational
Postapplication
exposure
section
of
this
document.
As
the
study
was
found
to
be
acceptable
for
the
risk
assessment,
the
highest
mean
residues
were
also
used
to
estimate
short­
term
(
DAT
0­
1)
for
irrigated
and
non­
irrigated
plots.
31
Only
limited
information
was
received
regarding
the
size
and
distribution
of
granular
formulations.
This
information
would
help
to
refine
or
characterize
the
estimate
of
potential
risk
from
episodic
incidental
ingestion
of
granules
beyond
the
current
screening
level.
If
the
particles
are
very
fine,
individual
grains
would
be
difficult
to
pick
up,
or
even
to
see
when
applied
on
a
lawn.
If
used
according
to
label
directions,
it
is
unlikely
that
oxadiazon
granules
would
be
accessible
to
a
child.
However,
larger
granules
or
pellets
of
a
few
millimeters
diameter
might
be
attractive
and
easily
picked
up
by
a
toddler.

3.2.3
Assumptions
Used
in
Postapplication
Exposure
Calculations
Dermal
Exposure
to
Golf
Course
Turfgrass
According
to
a
1992
report
from
The
Center
For
Golf
Course
Management,
12.2
percent
of
the
population
are
golfers
(
i.
e.,
28.5
million
people).
Golfing
is
considered
a
lifetime
sport
so
individuals
of
all
ages,
excluding
very
small
children,
routinely
play.
Children
who
are
12
years
of
age
or
older
are
likely
to
represent
the
vast
majority
of
the
youth
that
play
golf
on
any
sort
of
routine
basis.
However,
the
popularity
of
golf
as
a
recreational
pastime
has
increased
steadily
over
the
last
few
years
which
has
resulted
in
more
and
more
young
children
(
i.
e.,
less
than
12
years
old
for
this
discussion)
becoming
involved
in
the
sport.
Risk
assessments
for
these
age
children
are
more
difficult
to
complete
because
of
the
increased
uncertainties
associated
with
any
extrapolations
using
adult
dermal
exposure
data
and
because
of
the
increased
likelihood
that
other
behaviors
that
might
contribute
to
exposure
such
as
mouthing
contaminated
hands
or
golf
balls.

Dermal
exposures
are
calculated
using
the
standard
transfer
coefficient
approach
that
is
used
for
postapplication
exposure
assessments.
ADD(
t)
(
mg/
kg/
day)
=
((
TTR(
t)
(

g/
cm2)
x
TC
(
cm2/
hr)
x
ET(
hr/
day)
x
(
1
mg/
1000

g)
)/(
BW
(
kg))

Where:
ADD=
average
daily
dose
(
mg/
kg/
day)
at
time
(
t)
attributable
to
golfing
on
previously
treated
turf
(
mg/
kg/
day);
TTR(
t)=
turf
transferable
residue
at
time
(
t)
(

g/
cm2);
TC
=
transfer
coefficient
(
cm2/
hour);
ET
=
exposure
duration
(
hours);
and
BW
=
body
weight
(
kg).

°
Duration
is
4
hours
for
a
chemical
that
can
be
used
on
all
parts
of
a
course
(
greens,
tees,
and
fairways).
This
estimate
of
the
average
time
it
takes
to
play
a
round
of
golf
which
is
based
on
the
report
completed
by
the
Center
For
Golf
Course
Management
[
1992
Golf
Course
Operations:
Cost
of
Doing
Business/
Profitability.
Library
of
Congress
GV975.
G56
1992].

°
The
dose
levels
calculated
for
adult
golfers
can
be
considered
upper
level
estimates
of
exposure
because
of
several
reasons
including
the
clothing
scenario
considered
(
i.
e.,
shorts
and
short­
sleeved
shirts
are
not
worn
by
all
golfers),
combining
average
values
across
several
32
input
parameters
mathematically
results
in
an
upper
percentile
calculated
product.

°
Children
of
various
ages
down
to
the
very
young
(
e.
g.,
4
or
5
years
old)
are
currently
playing
golf,
the
agency
recognize
this
but
has
not
yet
developed
a
quantitative
approach
for
calculating
their
risk,
based
to
analysis
of
surface
area
to
body
weight
ratio
it
appears
that
the
dose
for
these
children
may
be
as
much
as
1.7
times
than
for
adults.

Dermal
Exposure
values
on
each
day
after
application
were
calculated
based
on
the
following
equation
(
see
Residential
2.2
(
1997):
Postapplication
dermal
potential
dose
from
pesticide
residues
on
turf):

DE(
t)
(
mg/
day)
=
(
TTR(
t)
(

g/
cm2)
x
TC
(
cm2/
hr)
x
Hr/
Day)/
1000
(

g/
mg)

Where:

DE
=
Dermal
exposure
at
time
(
t)
attributable
for
activity
in
a
previously
treated
area
(
mg/
day);
TTR
=
Turf
Transferable
Residue
at
time
(
t)
where
the
longest
duration
(
t)
is
dictated
by
the
kinetics
observed
in
the
TTR
study;
TC
=
Transfer
Coefficient;
and
Hr
=
Exposure
duration
in
hours.

The
activities
that
were
selected
as
the
basis
for
the
risk
assessment
are
represented
by
the
following
transfer
coefficients
(
for
short­
term
and
intermediate­
term
endpoints):

°
Transfer
Coefficient
=
500
cm2/
hour
for
adults
involved
in
a
low
exposure
activity
on
turf
such
as
golfing
or
light
work
activities;
based
on
Policy
Memo
#
003
.1
"
Agricultural
Transfer
Coefficients,"
Revised
­
August
7,
2000..
°
Transfer
Coefficient
=
14,500
cm2/
hour
for
adults
involved
in
a
high
exposure
activity
on
turf
such
as
heavy
yard
work;
Based
on
the
revised
residential
SOP
­
February
2001
°
Transfer
Coefficient
=
5200
cm2/
hour
for
toddler
involved
in
a
high
exposure
activity
on
turf
such
as
heavy
yard
work;
Based
on
the
revised
residential
SOP
­
February
2001
°
Transfer
Coefficient
=
7,400
cm2/
hour
(
non­
irrigated)
for
adults
involved
in
a
high
exposure
activity
on
turf
such
as
heavy
yard
work;
Based
on
the
submitted
re­
entry
study
(
MRID
#
435178­
01)
°
Transfer
Coefficient
=
4,300
cm2/
hour
(
irrigated)
for
adults
involved
in
a
high
exposure
activity
on
turf
such
as
heavy
yard
work;
Based
on
the
submitted
re­
entry
study
(
MRID
#
435178­
01)
and
°
Transfer
Coefficient
=
2,700
cm2/
hour
(
non­
irrigated)
for
toddlers
involved
in
a
high
exposure
activity.
Based
on
the
submitted
re­
entry
study
(
MRID
#
435178­
01)
°
Transfer
Coefficient
=
1,600
cm2/
hour
(
irrigated)
for
toddlers
involved
in
a
high
exposure
activity.
Based
on
the
submitted
re­
entry
study
(
MRID
#
435178­
01)
°
Transfer
Coefficient
=
16,500
cm2/
hour
for
sod
harvesting
(
hand
or
mechanical);
based
on
Policy
Memo
#
003
.1
"
Agricultural
Transfer
Coefficients,"
Revised
­
August
7,
2000.
33
PDR

(
DFR

SA

Freq

Hr

(
1mg/
1000

g))
The
Agency's
Residential
SOPs
contains
guidance
for
considering
children's
exposure
to
treated
turf.
The
dermal
calculations,
as
noted
above,
were
completed
based
on
the
guidance
provided
in
the
document.
All
nondietary
exposures
were
also
calculated
using
guidance
from
this
document.
Specifically,
the
kinds
of
nondietary
exposures
that
were
considered
in
this
assessment
include
the
following:

°
Dose
from
hand
to
mouth
activity
calculated
using
Residential
SOP
2.3.2:
Postapplication
potential
dose
among
toddlers
from
incidental
nondietary
ingestion
of
pesticide
residues
on
residential
lawns
from
hand­
to­
mouth
transfer.
°
Dose
from
mouthing
treated
turf
calculated
using
Residential
SOP
2.3.3:
Postapplication
potential
dose
among
toddlers
from
the
ingestion
of
pesticide
treated
turfgrass;
and
°
Dose
from
incidental
ingestion
of
soil
calculated
using
Residential
SOP
2.3.4:
Postapplication
potential
dose
among
toddlers
from
the
ingestion
of
soil
in
pesticide
treated
areas.

Although
incidental
exposures
incurred
by
hand­
to­
mouth
exposure
are
included
as
part
of
the
nondietary
risk
assessment,
these
type
of
exposures
are
considered
episodic
in
nature.
The
hand­
licking,
mouthing
of
turf,
and
eating
of
soil
are
considered
more
likely
to
co­
occur,
with
the
hand­
licking
constituting
the
largest
incidental
oral
exposure
component.

The
following
demonstrates
the
method
used
to
calculate
exposures
that
are
attributable
to
a
child
touching
treated
turf
and
then
putting
their
hands
in
their
mouth
(
SOP
2.3.2):

where:
PDR
=
potential
dose
rate
(
mg/
day)
DFR(
t)=
Dislodgeable
Residue
(
5%)
on
day
of
treatment
(

g/
cm2);
SA
=
surface
area
of
two
fingers
(
cm2);
Freq
=
frequency
of
hand­
to­
mouth
events
(
events/
hour);
and
Hr
=
exposure
duration
(
hours).

As
indicated
above,
the
dislodgeable
foliar
residue
represents
the
amount
of
pesticide
that
can
be
removed
from
turf
by
the
(
potentially
wet)
hands
of
a
child,
while
the
turf
transferable
residue
represents
the
amount
of
chemical
on
the
surfaces
of
treated
leaves
that
can
rub
off
on
dry
skin
or
clothing.
These
observations
are
based
on
empirical
data,
and
therefore
the
Residential
SOP
standard
5%
of
the
amount
ai
applied
is
used,
rather
than
the
data
from
the
TTR
study.
The
surface
area
for
1­
3
fingers
used
(
20
cm2)
is
the
median
surface
area
for
a
toddler
(
age
3
years)
as
updated
by
the
SAP
in
12/
99.
The
frequency
of
hand­
to­
mouth
events
is
20
events
per
hour
as
updated
in
12/
99.
The
2
hour
duration
value
is
a
recommended
value
from
the
U.
S.
EPA
Exposure
Factors
Handbook.
This
model
for
hand­
to­
mouth
dose
is
based
on
the
premise
that
a
child
puts
2­
3
fingers
in
their
mouths,
50%
of
the
residues
on
the
hands
are
transferred
from
the
hands
to
the
mouth,
and
that
all
of
the
dislodgeable
residues
available
on
the
treated
turf
transfer
to
the
child's
34
PDR

(
DFR

IgR

(
1mg/
1000

g))
hand
each
time
they
exhibit
this
behavior.

The
following
illustrates
the
approach
used
to
calculate
exposures
that
are
attributable
to
a
child
mouthing
treated
turf
(
SOP
2.3.3):

where:
PDR
=
potential
dose
rate
(
mg/
day);
DFR(
t)=
Dislodgeable
Foliar
Residue
(
DFR)
at
time
(
t)
where
the
longest
duration
(
t)
is
dictated
by
the
kinetics
observed
in
the
TTR
study
(

g/
cm2);
and
IgR=
ingestion
rate
for
mouthing
of
grass
per
day
(
cm2/
day).

The
ingestion
rate
used
(
25
cm2/
day)
assumes
that
a
child
will
grab
a
handful
of
turf,
mouth
it
and
remove
all
oxadiazon
residues,
and
then
remove
it
from
their
mouth
as
described
in
the
Residential
SOPs.
The
standard
time
period
is
2
hours,
as
explained
above.
The
surface
area
of
(
25
cm2/
day)
is
thought
to
approximate
a
handful
of
turf
that
is
mouthed.
The
maximum
average
TTR
values
were
used
for
this
scenario.

Incidental
Soil
Ingestion:

PDR
=
(
SR
t
*
IgR
*
CF1)

where:
PDR
=
potential
dose
rate
(
mg/
day)
SR
t
=
soil
residue
on
day
"
t"
(

g/
g),
assuming
average
day
of
reentry
"
t"
is
day
0
IgR
=
ingestion
rate
of
soil
(
mg/
day),
assumed
to
be
100
mg/
day
CF1
=
weight
unit
conversion
factor
to
convert
the

g
of
residues
on
the
soil
to
grams
to
provide
units
of
mg/
day
(
1E­
6
g/

g)
and
SR
t
=
AR
*
F
*
(
1­
D)
t
*
CF2
*
CF3
*
CF4
where:

AR
=
application
rate
(
lb
ai/
acre)
F
=
fraction
of
ai
available
in
uppermost
cm
of
soil
(
fraction/
cm),
assumed
to
be
100
percent
based
on
soil
incorporation
into
top
1
cm
of
soil
after
application
D
=
fraction
of
residue
that
dissipates
daily
(
unitless)
t
=
postapplication
day
on
which
exposure
is
being
assessed
CF2
=
weight
unit
conversion
factor
to
convert
the
lbs
ai
in
the
application
rate
to

g
for
the
soil
residue
value
(
4.54
x
108

g/
lb)
CF3
=
area
unit
conversion
factor
to
convert
the
surface
area
units
(
ft2)
in
the
application
rate
to
cm2
for
the
SR
value
(
2.47
x
10­
8
acre/
cm2
if
the
application
rate
is
per
acre)
35
CF4
=
volume
to
weight
unit
conversion
factor
to
convert
the
volume
units
(
cm3)
to
weight
units
for
the
SR
value
(
0.67
cm3/
g
soil)
t
=
postapplication
day
on
which
exposure
is
being
assessed,
assumed
to
be
day
zero
The
following
specific
assumptions
and
factors
were
used
in
order
to
complete
this
exposure
assessment:


These
assessments
were
based
on
the
guidance
provided
in
the
Residential
SOPs.
Several
of
the
assumptions
and
factors
used
in
the
exposure
assessment
are
described
in
that
document.


The
TTR
values
are
assumed
to
be
5
percent
of
the
application
rate
at
day
0
for
turfgrass
application
(
the
5
percent
rate
for
turfgrass
is
the
high
end
of
the
values
observed
in
Hurto
and
Prinster,
1993,
Goh
et
al.,
1986,
and
Cowell
et
al.,
1993,


Calculations
are
completed
at
the
maximum
application
rates
recommended
by
the
available
oxadiazon
labels
to
bracket
risk
levels
associated
with
the
various
use
patterns
and
activity
scenarios.


Due
to
a
lack
of
scenario­
specific
exposure
data,
HED
has
calculated
exposure
values
for
adults
using
surrogate
dermal
transfer
coefficients
that
represent
activities
such
as
mowing,
golfing,
and
yard
work.
Most
of
the
transfer
coefficients
used
are
based
on
data
submitted
by
the
ARTF
and
ORETF
and
are
reflected
in
the
revised
HED
exposure
guidance
Policy
3.1
(
8/
2000).

°
For
the
short­
and
intermediate­
term
risk
assessment,
the
equations
and
assumptions
used
for
each
of
the
scenarios
were
taken
from
the
Residential
SOPs
guidance
document.

°
Adults
were
assumed
to
weigh
60
kg
for
the
short
and
intermediate­
term
postapplication
dermal
dose
estimate.
Toddlers
(
3
years
old)
were
assumed
to
weigh
15
kg.

°
Postapplication
exposure
is
generally
assessed
on
the
same
day
the
pesticide
is
applied
because
it
is
assumed
that
the
resident
could
be
exposed
to
turf
immediately
after
application.

°
A
dermal
absorption
factor
of
9
%
was
used
in
the
calculation
of
short
and
intermediate­
term
postapplication
dermal
dose.
MOEs
were
calculated
using
the
same
formula
(
NOAEL
divided
by
absorbed
dermal
dose)
described
in
the
residential
handler
portion
of
this
chapter,
and
are
considered
to
be
below
the
level
of
concern
when
results
are
greater
than
100.

3.2.4
Postapplication
Exposure
Risk
Estimates
36
Using
the
revised
residential
SOP
postapplication
short­
and
intermediate­
term
dermal
risk
estimates
for
occupational
workers
are
between
30
and
1,000.
The
cancer
risk
for
all
occupational
handlers
is
between
9.92
x
10­
5
to
3.01
x
10­
6.

Dermal
postapplication
exposure
estimates
were
conducted
using
the
highest
mean
postapplication
residue
from
the
Jazzercise
study(
wettable
powder
formulations).
The
dermal
transfer
coefficients
from
the
Jazzercize
study
and
the
revised
residential
SOPs
were
used.
Using
the
Jazzercize
wettable
powder
application
study
residue
data
and
revised
residential
SOPs
,
all
of
the
scenario
had
short­
term
and
intermediate­
term
dermal
MOEs
greater
than
100
on
the
application
day
(
i.
e.,
day
0).
The
cancer
risks
for
all
residential
dermal
postapplication
is
between
6.22x
10­
6
to
7.51
x
10­
7
.

The
Residential
SOPs
and
submitted
Jazzercize
study
data
were
used
to
estimate
incidental
oral
exposure
for
toddlers
on
treated
turf.
The
short­
term
MOE
was100
for
the
toddler
hand­
tomouth
using
residential
SOPs
and
between
90
to
240
for
the
submitted
Jazzercize
study,
however
since
wettable
powder
formulation
has
a
higher
exposure
than
granular
formulation,
therefore
the
MOE,
s
can
be
considered
upper
level
estimates
of
exposure.
The
intermediate­
term
MOE
was
not
calculated
since
exposure
by
this
route
for
weeks
to
months
is
considered
less
likely
to
occur
than
short­
term
exposure.
Incidental
turfgrass
mouthing
and
soil
ingestion
had
MOEs
greater
than
100
for
short­
term
exposures
(
see
Appendix
C
Table
C4).

Under
the
Worker
Protection
Standard
(
WPS),
interim
restricted
entry
intervals
(
REI)
for
all
uses
within
the
scope
of
the
WPS
are
based
on
the
acute
toxicity
of
the
active
ingredient.
The
toxicity
categories
of
the
active
ingredient
for
acute
dermal
toxicity,
eye
irritation
potential,
and
skin
irritation
potential
are
used
to
determine
the
interim
WPS
REI.
If
one
or
more
of
the
three
acute
toxicity
effects
are
in
toxicity
category
I,
the
interim
WPS
REI
is
established
at
48
hours.
If
none
of
the
acute
toxicity
effects
are
in
category
I,
but
one
or
more
of
the
three
is
classified
as
category
II,
the
interim
WPS
REI
is
established
at
24
hours.
If
none
of
the
three
acute
toxicity
effects
are
in
category
I
or
II,
the
interim
WPS
REI
is
established
at
12
hours.(
all
of
the
three
oxadiazon
acute
toxicity
effects
are
in
category
III)
3.2.5
Data
Gaps
and
Uncertainties
The
following
data
gap
or
uncertainties
were
associated
with
this
assessment:

°
Granular
ingestion
is
considered
episodic,
rather
than
continuous,
in
nature.
37
APPENDIX
A
SHORT­
TERM
AND
INTERMEDIATE­
TERM
HANDLER
EXPOSURE
RISK
TABLES
A1
THROUGH
A4
38
Table
A1:
Occupational
Handler
Short­
term
and
Intermediate­
term
Risk
from
Oxadiazon
at
Baseline
Exposure
Scenario
(
Scenario
#)
Crop
type
Baseline
Dermal
Baseline
Inhalation
Total
MOEg
Unit
Exposure
(
mg/
lb
ai)
a
Daily
Dose
(
mg/
kg/
day)
b
Dermal
MOEc
Unit
Exposure
(
ug/
lb
ai)
d
Daily
Dose
(
mg/
kg/
day)
e
Inhalation
MOEf
Mixer/
Loader
Exposure
Mixing/
Loading
Wettable
Powders
for
Chemigation
Application
(
1a)
sod
farms
3.7
5.8
2.0
43
0.75
16
2
Mixing/
Loading
Wettable
Powders
for
Groundboom
Application
(
1b)
conifer
nurseries,
woody
ornamentals
0.89
14
0.11
100
12
herbaceous
ornamentals
0.67
18
0.086
140
16
sod
farms
1.3
9
0.17
70
8
golf
courses
0.89
14
0.11
100
12
Mixing/
Loading
Wettable
Powders
for
Rights­
of­
Way
Sprayer
(
1c)
roadside
turf,
ornamentals
0.89
14
0.11
100
12
Loading
Granular
formulations
(
2)
sod
farms,
conifers
forest
0.0084
0.004
3000
1.7
0.0091
1300
920
golf
course
turf,
parks,
recreational
areas
0.002
6000
0.0045
2600
1800
woody
ornamentals
0.002
6000
0.0045
2600
1800
Applicator
Applying
with
a
Groundboom
(
3)
sod
farms
0.014
0.005
2400
0.74
0.003
4100
1500
herbaceous
ornamentals
0.0025
4800
0.0015
8100
3000
golf
courses
0.0034
3600
0.002
6100
2300
conifer
nurseries,
woody
ornamentals
0.0034
3600
0.002
6100
2300
Applying
with
a
Rights­
of­
Way
Sprayer
(
4)
roadsides
1.3
0.31
38
3.9
0.01
1200
37
Applying
Wettable­
Powders
for
Handgun
Applicators
(
ORETF)
(
5)
lawns,
parks,
recreational
areas
See
PPE
See
PPE
See
PPE
1
0
36000
See
PPE
Applying
Granular
with
a
Tractor
Drawn
Spreader
(
6)
sod
farms
0.0099
0.0048
2500
1.2
0.0064
1900
1100
golf
courses
0.0099
0.0024
5100
1.2
0.0032
3800
2200
Table
A1:
Occupational
Handler
Short­
term
and
Intermediate­
term
Risk
from
Oxadiazon
at
Baseline
Exposure
Scenario
(
Scenario
#)
Crop
type
Baseline
Dermal
Baseline
Inhalation
Total
MOEg
Unit
Exposure
(
mg/
lb
ai)
a
Daily
Dose
(
mg/
kg/
day)
b
Dermal
MOEc
Unit
Exposure
(
ug/
lb
ai)
d
Daily
Dose
(
mg/
kg/
day)
e
Inhalation
MOEf
39
Mixer/
Loader/
Applicator
Backpack
Sprayer
(
LCO)
(
7)
lawns,
golf
courses,
ornamentals
nurseries
See
PPE
See
PPE
See
PPE
30
0.01
1200
See
PPE
Low
Pressure
Handwand
­
Wettable
Powder
Formulations
(
LCO)
(
8)
lawns,
golf
courses,
nursery
stock
29
0.87
14
1100
0.37
33
10
High
Pressure
Handwand
­­
(
Wettable
Powder
Formulations)
(
9)
woody
ornamentals,
conifer
nurseries.
See
PPE
See
PPE
See
PPE
120
0.04000
300
See
PPE
Lawn
Handgun
(
Wettable
Powder
Formulations)

(
ORETF)
(
10)
ornamentals,
lawns,
parks
rec
areas
0.99
0.022
560
62
0.021
580
280
Granulars
with
a
Push
Type
Spreader
(
ORETF)
(
11)
l
awn
s
,
g
o
l
f
c
o
u
r
s
e
s
,
p
a
r
k
s
,

recreational
areas,
ornamentals
0.35
0.011
1100
0.0075
2.50e­
06
4800000
1100
Granulars
with
a
Bellygrinder
(
LCO)
(
12)
golf
courses,
parks,
rec
areas.
10
0.06
200
62
0.0041
2900
190
a
Baseline
dermal
unit
exposure
scenarios
includes
long
pants,
long
shirts
and
no
gloves.

b
Daily
Dermal
Dose
(
mg/
kg/
day)
=
Daily
Dermal
Exposure
(
mg/
day)/
Body
weight
(
60
kg)*
Dermal
Absorption
Factor
(
9%)
.

c
Short­
term
or
Intermediate­
term
Dermal
MOE
=
NOAEL
(
12
mg/
kg/
day)/
Daily
Dermal
Dose
(
mg/
kg/
day).

d
Baseline
inhalation
unit
exposure
represents
no
respirator
e
Daily
Inhalation
Dose
(
mg/
kg/
day)
=
Daily
Inhalation
Exposure
(
mg/
day)/
Body
weight
(
60
kg).

f
Short­
term
or
Intermediate­
term
Inhalation
MOE
=
NOAEL
(
12
mg/
kg/
day)/
Daily
Inhalation
Dose
(
mg/
kg/
day).

g
Total
Dermal
MOE
=
1/
((
1/
Dermal
MOE)
+
(
1/
Inhalation
MOE)).
40
Table
A2:
Occupational
Handler
Short­
term
and
Intermediate­
term
Risk
from
Oxadiazon
at
PPE
Exposure
Scenario
(
Scenario
#)
Crop
type
PPE
Dermal
PPE
Inhalation
Total
MOEg
Unit
Exposure
(
mg/
lb
ai)
a
Daily
Dose
(
mg/
kg/
day)
b
Dermal
MOEc
Unit
Exposure
(
ug/
lb
ai)
d
Daily
Dose
(
mg/
kg/
day)
e
Inhalation
MOEf
Mixer/
Loader
Exposure
Mixing/
Loading
Wettable
Powders
for
Chemigation
Application
(
1a)
sod
farms
0.13
(
gl,
dl)
0.2
59
8.6
dust/

mist
respirator
0.15
80
35
Mixing/
Loading
Wettable
Powders
for
Groundboom
Application
(
1b)
conifer
nurseries,
woody
ornamentals
0.031
380
0.023
520
220
herbaceous
ornamentals
0.023
510
0.017
700
300
sod
farms
0.047
260
0.034
350
150
golf
courses
0.031
380
0.023
520
220
Mixing/
Loading
Wettable
Powders
for
Rights­
of­
Way
Sprayer
(
1c)
roadside
turf,
ornamentals
0.031
380
0.023
520
220
Loading
Granular
formulations
(
2)
sod
farms,
conifers
forest
NA
NA
NA
NA
NA
NA
NA
golf
course
turf,
parks,
recreational
areas
NA
NA
NA
NA
NA
woody
ornamentals
NA
NA
NA
NA
NA
Applicator
Applying
with
a
Groundboom
(
3)
sod
farms
NA
NA
NA
NA
NA
NA
herbaceous
ornamentals
NA
NA
NA
NA
NA
golf
courses
NA
NA
NA
NA
NA
conifer
nurseries,
woody
ornamentals
NA
NA
NA
NA
NA
Applying
with
a
Rights­
of­
Way
Sprayer
(
4)
roadsides
0.39
(
gl)
0.094
130
3.9
(
no
resp)
0.01
1200
120
Applying
Wettable­
Powders
for
Handgun
Applicators
(
ORETF)
(
5)
lawns,
parks,
recreational
areas
0.73
(
gl)
0.022
550
1.0
(
no
resp)
0.00030
36000
540
Applying
Granular
with
a
Tractor
Drawn
Spreader
(
6)
sod
farms
NA
NA
NA
NA
NA
NA
NA
golf
courses
NA
NA
NA
NA
NA
NA
NA
Table
A2:
Occupational
Handler
Short­
term
and
Intermediate­
term
Risk
from
Oxadiazon
at
PPE
Exposure
Scenario
(
Scenario
#)
Crop
type
PPE
Dermal
PPE
Inhalation
Total
MOEg
Unit
Exposure
(
mg/
lb
ai)
a
Daily
Dose
(
mg/
kg/
day)
b
Dermal
MOEc
Unit
Exposure
(
ug/
lb
ai)
d
Daily
Dose
(
mg/
kg/
day)
e
Inhalation
MOEf
41
Mixer/
Loader/
Applicator
Backpack
Sprayer
(
LCO)
(
7)
lawns,
golf
courses,
ornamentals
nurseries
2.5
(
gl)
0.075
160
30
(
no
resp)
0.01
1200
140
Low
Pressure
Handwand
­
Wettable
Powder
Formulations
(
LCO)
(
8)
lawns,
golf
courses,
nursery
stock
6.2
(
gl
dl)
0.19
65
220
dust/

mist
resp
0.073
160
46
High
Pressure
Handwand
­­
(
Wettable
Powder
Formulations)
(
9)
woody
ornamentals,
conifer
nurseries.
2.5
(
gl)
0.075
160
120
(
no
resp)
0.040
300
100
Lawn
Handgun
(
Wettable
Powder
Formulations)

(
ORETF)
(
10)
ornamentals,
lawns,
parks
rec
areas
NA
NA
NA
NA
NA
NA
NA
Granulars
with
a
Push
Type
Spreader
(
ORETF)

(
11)
lawns,
golf
courses,
parks,
recreational
areas,

ornamentals
NA
NA
NA
NA
NA
NA
NA
Granulars
with
a
Bellygrinder
(
LCO)
(
12)
golf
courses,
parks,
rec
areas.
NA
NA
NA
NA
NA
NA
NA
a
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.

b
Daily
Dermal
Dose
(
mg/
kg/
day)
=
Daily
Dermal
Exposure
(
mg/
day)/
Body
weight
(
60
kg)*
Dermal
Absorption
Factor
(
9%)
.

c
Short­
term
or
Intermediate­
term
Dermal
MOE
=
NOAEL
(
12
mg/
kg/
day)/
Daily
Dermal
Dose
(
mg/
kg/
day).

d
PPE
inhalation
unit
exposure
represents
dust/
mist
respirator
for
scenarios
1a,
1b,
1c,
and
8.

e
Daily
Inhalation
Dose
(
mg/
kg/
day)
=
Daily
Inhalation
Exposure
(
mg/
day)/
Body
weight
(
60
kg).

f
Short­
term
or
Intermediate­
term
Inhalation
MOE
=
NOAEL
(
12
mg/
kg/
day)/
Daily
Inhalation
Dose
(
mg/
kg/
day).

g
Total
Dermal
MOE
=
1/
((
1/
Dermal
MOE)
+
(
1/
Inhalation
MOE)).

NA=
Not
applicable
42
Table
A3:
Occupational
Handler
Short­
term
and
Intermediate­
term
Risk
from
Oxadiazon
at
Engineering
Control
Exposure
Scenario
(
Scenario
#)
Crop
type
PPE
Dermal
PPE
Inhalation
Total
MOEg
Unit
Exposure
(
mg/
lb
ai)
a
Daily
Dose
(
mg/
kg/
day)
b
Dermal
MOEc
Unit
Exposure
(
ug/
lb
ai)
d
Daily
Dose
(
mg/
kg/
day)
e
Inhalation
MOEf
Mixer/
Loader
Mixing/
Loading
Wettable
Powders
for
Chemigation
Application
(
1a)
sod
farms
0.0098
(
water
soluble
Packages)
0.015
780
0.24
0.00420
2900
610
Mixing/
Loading
Wettable
Powders
for
Groundboom
Application
(
1b)
conifer
nurseries,
woody
ornamentals
NA
NA
NA
NA
NA
herbaceous
ornamentals
NA
NA
NA
NA
NA
sod
farms
NA
NA
NA
NA
NA
golf
courses
NA
NA
NA
NA
NA
Mixing/
Loading
Wettable
Powders
for
Rights­
of­
Way
Sprayer
(
1c)
roadside
turf,
ornamentals
NA
NA
NA
NA
NA
Loading
Granular
formulations
(
2)
sod
farms,
conifers
forest
NA
NA
NA
NA
NA
NA
NA
golf
course
turf,
parks,
recreational
areas
NA
NA
NA
NA
NA
woody
ornamentals
NA
NA
NA
NA
NA
Applicator
Applying
with
a
Groundboom
(
3)
sod
farms
NA
NA
NA
NA
NA
NA
herbaceous
ornamentals
NA
NA
NA
NA
NA
golf
courses
NA
NA
NA
NA
NA
conifer
nurseries,
woody
ornamentals
NA
NA
NA
NA
NA
Applying
with
a
Rights­
of­
Way
Sprayer
(
4)
roadsides
NA
NA
NA
NA
NA
NA
NA
Applying
Wettable­
Powders
for
Handgun
Applicators
(
ORETF)

(
5)
lawns,
parks,
recreational
areas
NA
NA
NA
NA
NA
NA
NA
Applying
Granular
with
a
Tractor
Drawn
Spreader
(
6)
sod
farms
NA
NA
NA
NA
NA
NA
NA
Table
A3:
Occupational
Handler
Short­
term
and
Intermediate­
term
Risk
from
Oxadiazon
at
Engineering
Control
Exposure
Scenario
(
Scenario
#)
Crop
type
PPE
Dermal
PPE
Inhalation
Total
MOEg
Unit
Exposure
(
mg/
lb
ai)
a
Daily
Dose
(
mg/
kg/
day)
b
Dermal
MOEc
Unit
Exposure
(
ug/
lb
ai)
d
Daily
Dose
(
mg/
kg/
day)
e
Inhalation
MOEf
43
golf
courses
NA
NA
NA
NA
NA
NA
NA
Mixer/
Loader/
Applicator
Backpack
Sprayer
(
LCO)
(
7)
lawns,
golf
courses,
ornamentals
nurseries
NA
NA
NA
NA
NA
NA
NA
Low
Pressure
Handwand
­
Wettable
Powder
Formulations
(
LCO)

(
8)
lawns,
golf
courses,
nursery
stock
NF
NF
NF
NF
NF
NF
NF
High
Pressure
Handwand
­­
(
Wettable
Powder
Formulations)
(
9)
woody
ornamentals,
conifer
nurseries.
NA
NA
NA
NA
NA
NA
NA
Lawn
Handgun
(
Wettable
Powder
Formulations)
(
ORETF)
(
10)
ornamentals,
lawns,
parks
rec
areas
NA
NA
NA
NA
NA
NA
NA
Granulars
with
a
Push
Type
Spreader
(
ORETF)
(
11)
l
awns,
gol
f
c
o
u
r
s
e
s
,
p
a
rk
s,

recreational
areas,
ornamentals
NA
NA
NA
NA
NA
NA
NA
Granulars
with
a
Bellygrinder
(
LCO)
(
12)
golf
courses,
parks,
rec
areas.
NA
NA
NA
NA
NA
NA
NA
a
Engineering
Control
dermal
unit
exposure
scenarios
includes
long
pants,
long
shirts,
gloves
and
water
soluble
packages
for
scenario
1a.

b
Daily
Dermal
Dose
(
mg/
kg/
day)
=
Daily
Dermal
Exposure
(
mg/
day)/
Body
weight
(
60
kg)*
Dermal
Absorption
Factor
(
9%)
.

c
Short­
term
or
Intermediate­
term
Dermal
MOE
=
NOAEL
(
12
mg/
kg/
day)/
Daily
Dermal
Dose
(
mg/
kg/
day).

d
inhalation
unit
exposure
represents
no
respirator
e
Daily
Inhalation
Dose
(
mg/
kg/
day)
=
Daily
Inhalation
Exposure
(
mg/
day)/
Body
weight
(
60
kg).

f
Short­
term
or
Intermediate­
term
Inhalation
MOE
=
NOAEL
(
12
mg/
kg/
day)/
Daily
Inhalation
Dose
(
mg/
kg/
day).

g
Total
Dermal
MOE
=
1/
((
1/
Dermal
MOE)
+
(
1/
Inhalation
MOE)).

NA
=
Not
applicable
NF
=
Not
feasible
44
Table
A4
:
Exposure
Scenario
Descriptions
for
the
Use
of
Oxadiazon
Exposure
Scenario
#
Data
Source
Standard
Assumptionsa
(
8­
hr
work
day)
Commentsb
Mixer/
Loader
Descriptors
Mixing/
Loading
Wettable
Powder
Formulations
(
1a/
1b/
1c)
PHED
V1.1
350
acres
for
chemigation,

80
acres
for
groundboom
in
sod
farms,
40
acres
for
groundboom
on
golf
course
turf,
5
acres/
day
for
the
turf
loading
scenarios
Baseline:
Hands,
dermal
and
inhalation
=
ABC
grades.
Hands
=
7
replicates,
dermal
=
22­
45
replicates
and
inhalation
=
44
replicates.
Low
confidence
in
dermal,
hands
data
due
to
the
low
number
of
hand
replicates.
Medium
confidence
in
inhalation
data.

PPE:
Gloved
data
for
hands
=
ABC
grades.
Hands
=
24
replicates.
Medium
confidence
in
hands
data.

Dermal
values
calculated
by
applying
a
50%
protection
factor
to
baseline
values
to
account
for
an
additional
layer
of
clothing.
A
5­
fold
PF
(
e.
g.
80%
PF
was
applied
to
the
baseline
inhalation
data).

Engineering
Controls:
Water
soluble
bags.
Dermal
=
AB
grades.
Hands
and
inhalation
=
All
grade.

Inhalation
=
15
replicates,
dermal
=
6­
15
replicates
and
hands
=
5
replicates.
Low
confidence
in
the
dermal,
hands
and
inhalation
data.

Loading
Granular
Formulations
(
2)
PHED
V1.1
80
acres
for
tractor
drawn
spreaders
for
most
crops;
40
acres
for
golf
course
turf
Baseline:
Low
confidence
in
dermal
and
hand
data
(
due
to
low
hand
replicates).
High
confidence
in
inhalation
data.
No
protection
factors
were
needed
to
define
the
unit
exposure
values.

Applicator
Descriptors
Groundboom
Application
(
3)
PHED
V1.1
80
acres
for
tractor
drawn
spreaders
for
sod
farms;
40
acres
for
golf
course
turf
Baseline:
Dermal
(
23
to
42
replicates);
hand
(
29
replicates);
and
inhalation
(
22
replicates)
exposure
values
are
based
on
AB
grade
data.
High
confidence
in
the
unit
exposure
values.
No
protection
factors
were
required
to
define
the
unit
exposure
value.

Applying
Liquids
with
Rights­
of­

Way
Sprayer
(
4)
PHED
V1.1
40
acres
Baseline:
Dermal
(
4
to
20
replicates)
exposure
value
is
based
on
ABC
grade
data.
Hand
(
16
replicates)

exposure
value
based
on
AB
grade
data
and
inhalation
(
16
replicates)
exposure
value
is
based
on
A
grade
data.
Low
confidence
in
the
dermal
unit
exposure
value
and
high
confidence
in
the
inhalation
data.
No
protection
factors
were
needed
to
define
the
unit
exposure
value.

PPE:
The
same
dermal
and
inhalation
data
are
used
as
for
the
baseline
coupled,
if
needed,
with
a
50%

protection
factor
to
account
for
an
additional
layer
of
clothing
and
an
80%
protection
factor
to
account
for
the
use
of
a
dust/
mist
respirator.
Gloved­
hand
(
4
replicates)
exposure
value
is
based
on
AB
grade
data.
Low
confidence
in
the
dermal/
hand
unit
exposure
value.

Engineering
Controls:
Not
available
for
this
scenario.

Applying
Liquids
with
a
Handgun
(
5)
(
ORTEF)
ORTEF
5
acres
Baseline:
Inhalation
(
90
replicates)
exposure
value
is
based
on
B
grade
data.

PPE:
Hand
(
90
replicates)
and
dermal
(
90
replicates)
exposure
values
are
based
on
B
grade
data.

Engineering
Controls:
Not
available
for
this
scenario
Applying
Granulars
with
a
Tractor
Drawn
Spreader
(
6)
PHED
V1.1
40
acres
for
golf
course
turf
Baseline:
Low
confidence
in
hand,
dermal,
and
inhalation
data.
No
protection
factors
were
required
to
define
the
unit
exposure
values.

Mixer/
Loader/
Applicator
Descriptors
Table
A4
:
Exposure
Scenario
Descriptions
for
the
Use
of
Oxadiazon
Exposure
Scenario
#
Data
Source
Standard
Assumptionsa
(
8­
hr
work
day)
Commentsb
45
Mixing/
Loading/
Applying
with
a
Backpack
Sprayer
(
7)
PHED
V1.1
5
acres
for
occupational
uses
Baseline:
Only
low
confidence
inhalation
data
available
(
no
non­
gloved
hand
monitoring
data
are
available,
therefore
the
assessment
was
not
completed).

PPE:
Low
confidence
single
layer
clothing
dermal
monitoring
data
available,
coupled
with
a
50%

protection
factor
to
account
for
an
additional
layer
of
clothing.
Inhalation
data
coupled
with
a
90%

protection
factor
to
account
for
the
use
of
a
respirator.
Hand
exposure
data
with
gloves
were
monitored
(
considered
low
confidence).

Engineering
Controls:
Not
feasible
Mixing/
Loading/
Applying
Liquids
with
a
Low
Pressure
Handwand
(
8)
PHED
V1.1
5
acres
for
occupational
uses
Baseline:
Dermal
and
inhalation
data
=
ABC
grades,
and
hands
data
=
All
grade.
Dermal
=
9­
80
replicates;
hands
=
70
replicates;
and
inhalation
=
80
replicates.
Low
confidence
in
hands,
dermal
data.

Medium
confidence
in
inhalation
data.

PPE
and
Engineering
Controls:
Not
required
for
assessment.

Mixing/
Loading/
Applying
with
a
High
Pressure
Handwand
(
9)
PHED
V1.1
5
acres
Baseline:
Only
low
confidence
inhalation
data
available
(
no
non­
gloved
hand
monitoring
data
are
available,
therefore
the
assessment
was
not
completed).

PPE:
Low
confidence
single
layer
clothing
dermal
monitoring
data
available,
coupled
with
a
50%

protection
factor
to
account
for
an
additional
layer
of
clothing.
Inhalation
data
coupled
with
a
90%

protection
factor
to
account
for
the
use
of
a
respirator.
Hand
exposure
data
with
gloves
were
monitored
(
considered
low
confidence).

Engineering
Controls:
Not
feasible
Mixing/
Loading/
Applying
with
a
Handgun
(
turf
grass
application)

(
10)
ORTEF
5
acres
for
occupational
uses.
Data
for
open
mixing
of
liquids
and
handgun
turfgrass
application
were
combined
to
generate
mixer/
loader/
applicator
value
as
this
is
the
most
likely
exposure
scenario.

Baseline
for
application:
Low
confidence
in
hand,
dermal,
and
inhalation
data.
Baseline
dataset
was
based
on
the
use
of
chemical­
resistant
gloves.
Therefore,
a
reverse
80%
PF
was
used
on
the
gloved
hand
data
to
assess
baseline
exposure
for
individuals
wearing
no
gloves
(
i.
e.,
it
is
a
typical
use
scenario
demanding
a
baseline
assessment
and
the
exposures
are
generally
lower
compared
with
other
handheld
methods).

PPE
for
applicator:
As
appropriate,
the
same
dermal,
hand,
and
inhalation
data
are
used
as
for
the
baseline
coupled
with
a
50%
protection
factor
to
account
for
an
additional
layer
of
clothing
and
a
80%

protection
factor
to
account
for
the
use
of
a
respirator.
Hand
exposure
data
with
gloves
were
monitored
(
considered
low
confidence).

Engineering
Controls:
Not
feasible.

Mixing/
Loading/
Applying
with
a
Push­
Type
Granular
Spreader
(
11)
ORTEF
5
acres
for
occupational
uses.
Baseline:
Low
confidence
in
the
dermal
and
hand
data.
High
confidence
in
the
inhalation
data.
No
protection
factors
were
required
to
define
the
unit
exposure
values
(
a
50
percent
protection
factor
was
used
to
back
calculate
the
homeowner
exposure
scenario).

Mixing/
Loading/
Applying
with
a
Bellygrinder
(
12)
PHED
V1.1
5
acres
for
occupational
uses.
Baseline:
Medium
confidence
in
hand
and
dermal
data.
High
confidence
in
inhalation
data.
No
protection
factors
were
required
to
define
the
unit
exposure
values
(
also
applies
to
homeowner
scenarios).

a
All
Standard
Assumptions
are
based
on
a
typical
work
day
(
the
components
that
involve
pesticide
use)
as
estimated
by
HED.

b
All
handler
exposure
assessments
in
this
document
are
based
on
the
"
Best
Available"
data
as
defined
by
the
PHED
SOP
for
meeting
Subdivision
U
Guidelines
(
i.
e.,
completing
exposure
assessments).
Best
available
grades
are
assigned
to
data
as
follows:
matrices
with
A
and
B
grade
data
(
i.
e.,
Acceptable
Grade
Data)
and
a
minimum
of
15
replicates;
if
not
available,
then
grades
46
A,
B
and
C
data
and
a
minimum
of
15
replicates;
if
not
available,
then
all
data
regardless
of
the
quality
(
i.
e.,
All
Grade
Data)
and
number
of
replicates.
Generic
data
confidence
categories
are
assigned
as
follows:

High
=
grades
A
and
B
and
15
or
more
replicates
per
body
part
Medium
=
grades
A,
B,
and
C
and
15
or
more
replicates
per
body
part
Low
=
grades
A,
B,
C,
D
and
E
or
any
combination
of
grades
with
less
than
15
replicates.

Protection
factors
applied
to
exposure
data
for
the
use
of
respiratory
protection,
protection
afforded
with
the
use
of
an
additional
layer
of
clothing,
and
protection
from
the
use
of
chemical
resistant
gloves
are
as
follows:
90
%
(
respirator);
50
%
(
layer
of
clothing);
and
90%
(
gloves).
47
APPENDIX
B
OCCUPATIONAL
HANDLER
CANCER
(
Q*)
RISKS
TABLES
B1
­
B4
48
Table
B1:
Occupational
Handler,
Cancer
(
Q*)
Risk
from
Oxadiazon
at
baseline
Exposure
Scenario
#
Crop
Type
Total
Baseline
Daily
Dose
(
mg/
kg/
day)
a
Baseline
Daily
LADDb
3/
30
days
Baseline
Riskc
Mixer/
Loader
Exposure
Mixing/
Loading
Wettable
Powders
for
Chemigation
Application
(
1a)
sod
farms
5.600
2.30e­
02/
2.30e­
01
1.65e­
03/
1.65­
02
Mixing/
Loading
Wettable
Powders
for
Groundboom
Application
(
1b)
conifer
nurseries,
woody
ornamentals
0.860
3.50e­
03/
3.5e­
02
2.51e­
04/
2.51e­
03
herbaceous
ornamentals
0.640
2.60e­
03/
2.60e­
02
1.88e­
04/
1.88e­
03
sod
farms
1.300
5.30e­
03/
5.30e­
02
3.77e­
04/
3.77e­
03
golf
courses
0.860
3.50e­
03/
3.50e­
02
2.51e­
04/
2.51e­
03
Mixing/
Loading
Wettable
Powders
for
Rights­
of­
Way
Sprayer
(
1c)
roadside
turf,
ornamentals
0.860
3.50e­
03/
3.50e­
02
3.14e­
05/
3.14e­
04
Loading
Granular
formulations
(
2)
sod
farms,
conifers
forest
0.011
4.60e­
04/
4.60e­
03
3.28e­
06/
3.28e­
05
golf
course
turf,
parks,
recreational
areas
0.0056
2.30e­
05/
2.30e­
04
1.64e­
06/
1.64e­
05
woody
ornamentals
0.0056
2.30e­
05/
2.30e­
04
1.64e­
06/
1.64e­
05
Applicator
Applying
with
a
Groundboom
(
3)
sod
farms
0.007
2.80e­
05/
2.80e­
04
2.00e­
06/
2.00e­
05
herbaceous
ornamentals
0.003
1.40e­
05/
1.40e­
04
1.00e­
06/
1.00e­
05
golf
courses
0.005
1.90e­
05/
1.90e­
04
1.34e­
06/
1.34e­
05
conifer
nurseries,
woody
ornamentals
0.005
1.90e­
05/
1.90e­
04
1.34e­
06/
1.34e­
05
Applying
with
a
Rights­
of­
Way
Sprayer
(
4)
roadsides
0.280
1.10e­
03/
1.10e­
02
8.07e­
05/
8.07e­
04
Applying
Wettable­
Powders
for
Handgun
Applicators
(
ORETF)
(
5)
lawns,
parks,
recreational
areas
See
PPE
See
PPE
See
PPE/

Applying
Granular
with
a
Tractor
Drawn
Spreader
(
6)
sod
farms
0.010
1.30e­
05/
1.30e­
04
9.31e­
07/
9.31e­
06
golf
courses
0.005
6.50e­
06/
6.50e­
05
4.66e­
07/
4.66e­
06
Mixer/
Loader/
Applicator
Backpack
Sprayer
(
LCO)
(
7)
lawns,
golf
courses,
ornamentals
nurseries
See
PPE
See
PPE
See
PPE
Low
Pressure
Handwand
­
Wettable
Powder
Formulations
(
LCO)
(
8)
lawns,
golf
courses,
nursery
stock
1.060
4.40e­
03/
4.40e­
02
3.10e­
04/
3.10e­
03
Table
B1:
Occupational
Handler,
Cancer
(
Q*)
Risk
from
Oxadiazon
at
baseline
Exposure
Scenario
#
Crop
Type
Total
Baseline
Daily
Dose
(
mg/
kg/
day)
a
Baseline
Daily
LADDb
3/
30
days
Baseline
Riskc
49
High
Pressure
Handwand
­­
(
Wettable
Powder
Formulations)
(
9)
woody
ornamentals,
conifer
nurseries.
See
PPE
See
PPE
See
PPE
Lawn
Handgun
(
Wettable
Powder
Formulations)
(
ORETF)
(
10)
ornamentals,
lawns,
parks
rec
areas
0.036
1.50e­
04/
1.50e­
03
1.06e­
05/
1.06e­
04
Granulars
with
a
Push
Type
Spreader
(
ORETF)
(
11)
lawns,
golf
courses,
parks,
recreational
areas,

ornamentals
0.008
3.30e­
05/
3.30e­
04
2.33e­
06/
2.33e­
05
Granulars
with
a
Bellygrinder
(
LCO)
(
12)
golf
courses,
parks,
rec
areas.
0.055
2.30e­
04/
2.30e­
03
1.61e­
05/
1.61e­
04
a
Baseline
Total
Daily
Dose
=
[
Baseline
Daily
Dermal
Exposure
(
mg/
day)
*
Dermal
absorption
factor
(
9%)
+
Baseline
Daily
Inhalation
Exposure
(
mg/
day)]/
Body
Weight
(
70
kg).

b
Baseline
LADD
(
mg/
kg/
day)
=
Baseline
Total
Daily
Dose
(
mg/
kg/
day)
*
(
Number
of
days
exposed
per
year)
/
365
days
per
year)
*
35
years
worked/
70
year
lifetime.

c
Baseline
Total
Cancer
Risk
=
Baseline
LADD
(
mg/
kg/
day)
*
(
Q
1*),
where
Q
1*
=
7.11e­
2
(
mg/
kg/
day)­
1.

Baseline
cancer
risk
includes
long
pants,
long
shirts
no
gloves
and
no
respirator.

Two
exposure
frequencies
were
used
for
cancer,
the
first
represented
the
maximum
number
of
applications
per
site
per
season
to
represent
private
use
(
3),
and
the
second
frequency
applied
a
factor
of
ten
to
the
first
frequency
to
represent
commercial
handlers
making
multiple
applications
per
site
per
season
(
30).
50
Table
B2:
Occupational
Handler,
Cancer
(
Q*)
Risk
from
Oxadiazon
at
PPE
Exposure
Scenario
#
Crop
Type
Total
PPE
1
Daily
Dose
(
mg/
kg/
day)
a
PPE
1
LADDb
3/
30
days
PPE
1
Riskc
Total
PPE
2
Daily
Dose
(
mg/
kg/
day)
a
PPE
2
LADDb
3/
30
days
PPE2
Riskc
Mixer/
Loader
Exposure
Mixing/
Loading
Wettable
Powders
for
Chemigation
Application
(
1a)
sod
farms
0.870
3.58e­
03/

3.58e­
02
2.56e­
04/

2.56e­
03
0.82
3.37e­
01/

3.37e­
02
2.40e­
04/

2.40e­
03
Mixing/
Loading
Wettable
Powders
for
Groundboom
Application
(
1b)
conifer
nurseries,
woody
ornamentals
0.130
5.48e­
04/

5.48e­
03
3.89e­
05/

3.89e­
04
0.130
5.14e­
4/

5.14e­
03
3.65e­
05/

3.65e­
04
herbaceous
ornamentals
0.100
4.11e­
04/

4.11e­
03
2.92e­
05/

2.92e­
04
0.094
3.85e­
04/

3.85e­
03
2.74e­
05/

2.74e­
04
sod
farms
0.200
8.22e­
04/

8.22e­
03
5.84e­
05/

5.84e­
04
0.190
7.71e­
04/

7.71e­
03
5.48e­
05/

5.48e­
04
golf
courses
0.130
5.48e­
04/

5.48e­
03
3.89e­
05/

3.89e­
04
0.130
5.14e­
04/

5.14e­
04
3.65e­
05/

3.65e­
04
Mixing/
Loading
Wettable
Powders
for
Rights­
of­
Way
Sprayer
(
1c)
roadside
turf,
ornamentals
0.130
5.48e­
04/

5.48e­
03
3.89e­
05/

3.89e­
04
0.016
5.14e­
04/

5.14e­
03
4.57e­
06/

4.57e­
04
Loading
Granular
formulations
(
2)
sod
farms,
conifers
forest
0.011
4.36e­
05/

4.36e­
04
3.10e­
06/

3.10e­
05
0.009
3.77e­
05/

3.77e­
04
2.68e­
06/

2.68e­
05
golf
course
turf,
parks,
recreational
areas
0.005
2.18e­
05/

2.18e­
04
1.55e­
06/

1.55e­
05
0.0046
1.88e­
05/

1.88e­
04
1.34e­
06/

1.34e­
05
woody
ornamentals
0.005
2.18e­
05/

2.18e­
04
1.55e­
06/

1.55e­
05
0.0046
1.88e­
05/

1.88e­
04
1.34e­
06/

1.34e­
05
Applicator
Applying
with
a
Groundboom
(
3)
sod
farms
0.007
2.82e­
05/

2.82e­
04
2.00E­
06/

2.00e­
05
0.0059
2.44e­
05/

2.44e­
04
1.73e­
06/

1.73e­
05
herbaceous
ornamentals
0.003
1.41e­
05/

1.41e­
04
1.00e­
06/

1.00e­
05
0.003
1.22e­
05/

1.22e­
04
8.67e­
07/

8.67e­
06
golf
courses
0.005
1.88e­
05/

1.88e­
04
1.34e­
06/

1.34e­
05
0.004
1.63e­
05/

1.63e­
04
1.16e­
06/

1.16e­
05
conifer
nurseries,
woody
ornamentals
0.005
1.88e­
05/

1.88e­
04
1.34e­
06/

1.34e­
05
0.004
1.63e­
05/

1.63e­
04
1.16e­
06/

1.16e­
05
Table
B2:
Occupational
Handler,
Cancer
(
Q*)
Risk
from
Oxadiazon
at
PPE
Exposure
Scenario
#
Crop
Type
Total
PPE
1
Daily
Dose
(
mg/
kg/
day)
a
PPE
1
LADDb
3/
30
days
PPE
1
Riskc
Total
PPE
2
Daily
Dose
(
mg/
kg/
day)
a
PPE
2
LADDb
3/
30
days
PPE2
Riskc
51
Applying
with
a
Rights­
of­
Way
Sprayer
(
4)
roadsides
0.890
3.66e­
04/

3.66e­
03
2.60e­
05/

2.60e­
04
0.069
2.82e­
04/

2.82e­
03
2.00e­
05/

2.00e­
04
Applying
Wettable­
Powders
for
Handgun
Applicators
(
ORETF)
(
5)
lawns,
parks,
recreational
areas
0.019
7.83e­
05/

7.83e­
04
5.57e­
06/

5.57e­
05
0.010
4.13e­
05/

4.13e­
04
2.94e­
06/

2.94e­
05
Applying
Granular
with
a
Tractor
Drawn
Spreader
(
6)
sod
farms
0.008
1.16e­
05/

1.16e­
04
8.23e­
07/

8.23e­
05
0.0072
9.88e­
06/

9.88e­
05
7.03e­
07/

7.03e­
06
golf
courses
0.004
5.79e­
06/

5.79e­
05
4.11e­
07/

4.11e­
06
0.0036
4.94e­
06/

4.94e­
05
3.51e­
07/

3.51e­
06
Mixer/
Loader/
Applicator
Backpack
Sprayer
(
LCO)
(
7)
lawns,
golf
courses,
ornamentals
nurseries
0.073
2.99e­
04/

2.99e­
03
2.13e­
05/

2.13e­
04
0.05
2.04e­
04/

2.04e­
03
1.45e­
05/

1.45e­
04
Low
Pressure
Handwand
­
Wettable
Powder
Formulations
(
LCO)

(
8)
lawns,
golf
courses,
nursery
stock
0.540
2.20e­
03/

2.20e­
03
1.56e­
04/

1.56e­
03
0.47
1.95e­
03/

1.95e­
02
1.38e­
04/

1.38e­
03
High
Pressure
Handwand
­­
(
Wettable
Powder
Formulations)
(
9)
woody
ornamentals,
conifer
nurseries.
0.064
2.64e­
04/

2.64e­
03
1.88e­
05/

1.88e­
04
0.041
1.69e­
04/

1.69e­
03
1.20e­
05/

1.20e­
04
Lawn
Handgun
(
Wettable
Powder
Formulations)
(
ORETF)
(
10)
ornamentals,
lawns,
parks
rec
areas
0.036
1.49e­
04/

1.49e­
03
1.06e­
05/

1.06e­
04
0.027
1.13e­
04/

1.13e­
03
8.03e­
06/

8.03e­
05
Granulars
with
a
Push
Type
Spreader
(
ORETF)
(
11)
l
a
wn
s
,
g
o
l
f
c
o
u
r
s
e
s
,
p
a
r
k
s
,

recreational
areas,
ornamentals
0.006
2.54e­
05/

2.54e­
04
1.80e­
06/

1.80e­
05
No
Data
No
Data
No
data
Granulars
with
a
Bellygrinder
(
LCO)
(
12)
golfcourses,
parks,
rec
areas.
0.051
2.11e­
04/

2.11e­
03
1.50e­
05/

1.50e­
04
0.033
1.35e­
04/

1.35e­
03
9.60e­
06/

9.60e­
05
a
PPE1,
2
Total
Daily
Dose
=
[
PPE
Daily
Dermal
Exposure
(
mg/
day)
*
Dermal
absorption
Factor
(
9%)
+
baseline
Daily
Inhalation
Exposure
(
mg/
day)]/
Body
Weight
(
70
kg).

b
PPE1,
2
LADD
(
mg/
kg/
day)
=
PPE
Total
Daily
Dose
(
mg/
kg/
day)
*
(
Number
of
days
exposed
per
year)
/
365
days
per
year)
*
35
years
worked/
70
year
lifetime.

C
PPE1,
2
Total
Cancer
Risk
=
PPE
LADD
(
mg/
kg/
day)
*
(
Q
1*),
where
Q
1*
=
7.11e­
2
(
mg/
kg/
day)­
1.

PPE
1
cancer
risk
includes
long
pants,
long
shirts,
gloves
and
no
respirator.

PPE
2
cancer
risk
includes
long
pants,
long
shirts,
double
layer,
gloves
and
no
respirator.

Two
exposure
frequencies
were
used
for
cancer,
the
first
represented
the
maximum
number
of
applications
per
site
per
season
to
represent
private
use
(
3),
and
the
second
frequency
applied
a
factor
of
ten
to
the
first
frequency
to
represent
commercial
handlers
making
multiple
applications
per
site
per
season
(
30).
52
Table
B3:
Occupational
Handler,
Cancer
(
Q*)
Risk
from
Oxadiazon
at
PPE
Exposure
Scenario
#
Crop
Type
Total
PPE
3
Daily
Dose
(
mg/
kg/
day)
a
PPE
3
LADDb
3/
30
days
PPE
3
Riskc
Total
PPE
4
Daily
Dose
(
mg/
kg/
day)
a
PPE
4
LADDb
3/
30
days
PPE
4
Riskc
Mixer/
Loader
Exposure
Mixing/
Loading
Wettable
Powders
for
Chemigation
Application
(
1a)
sod
farms
0.360
1.47e­
03/

1.47e­
02
1.05E­
04/

1.05e­
03
0.3
1.25e­
03/

1.25e­
02
8.90e­
05/

8.90e­
04
Mixing/
Loading
Wettable
Powders
for
Groundboom
Application
(
1b)
conifer
nurseries,
woody
ornamentals
0.055
2.25e­
04/

2.25e­
03
1.60e­
05/

1.60e­
04
0.046
1.91e­
04/

1.91e­
03
1.36e­
05/

1.36e­
04
herbaceous
ornamentals
0.041
1.68e­
04/

1.68e­
03
1.20e­
05/

1.20e­
04
0.035
1.43e­
04/

1.43e­
03
1.02e­
05/

1.02e­
04
sod
farms
0.082
3.37e­
04/

3.37e­
03
2.39e­
05/

2.39e­
04
0.070
2.86e­
04/

2.86e­
03
2.03e­
05/

2.03e­
04
golf
courses
0.055
2.25e­
04/

2.25e­
03
1.60e­
05/

1.60e­
04
0.046
1.91e­
04/

1.91e­
03
1.36e­
05/

1.36e­
04
Mixing/
Loading
Wettable
Powders
for
Rights­
of­
Way
Sprayer
(
1c)
roadside
turf,
ornamentals
0.055
2.25e­
04/

2.25e­
03
1.60e­
05/

1.60e­
04
0.046
1.91e­
04/

1.91e­
03
1.36e­
05/

1.36e­
04
Loading
Granular
formulations
(
2)
sod
farms,
conifers
forest
0.004
1.81e­
05/

1.81e­
04
1.28e­
06/

1.28e­
05
0.003
1.21e­
05/

1.21e­
04
8.63e­
07/

8.63e­
06
golf
course
turf,
parks,

recreational
areas
0.002
9.03e­
06/

9.03e­
05
6.42e­
07/

6.42e­
06
0.0015
6.07e­
06/

6.07e­
05
4.31e­
07/

4.31e­
06
woody
ornamentals
0.002
9.03e­
06/

9.03e­
07
6.42e­
07/

6.42e­
06
0.0015
6.07e­
06/

6.07e­
05
4.31e­
07/

4.31e­
06
Applicator
Applying
with
a
Groundboom
(
3)
sod
farms
0.005
1.99e­
05/

1.99e­
04
1.41e­
06/

1.41e­
05
0.0039
1.61e­
05/

1.61e­
04
1.14e­
06/

1.14e­
05
herbaceous
ornamentals
0.002
9.93e­
06/

9.93e­
05
7.06e­
07/

7.06e­
06
0.002
8.03e­
06/

8.03e­
05
5.71e­
07/

5.71e­
06
golf
courses
0.003
1.32e­
05/

1.32e­
04
9.42e­
07/

9.42e­
06
0.003
1.07e­
05/

1.07e­
04
7.61e07/

7.61e­
06
conifer
nurseries,
woody
ornamentals
0.003
1.32e­
05/

1.32e­
04
9.42e07/

9.42e­
06
0.003
1.07e­
05/

1.07e­
04
7.61e07/

7.61e­
06
Table
B3:
Occupational
Handler,
Cancer
(
Q*)
Risk
from
Oxadiazon
at
PPE
Exposure
Scenario
#
Crop
Type
Total
PPE
3
Daily
Dose
(
mg/
kg/
day)
a
PPE
3
LADDb
3/
30
days
PPE
3
Riskc
Total
PPE
4
Daily
Dose
(
mg/
kg/
day)
a
PPE
4
LADDb
3/
30
days
PPE
4
Riskc
53
Applying
with
a
Rights­
of­
Way
Sprayer
(
4)
roadsides
0.082
3.37e­
04/

3.37e­
03
2.40e­
05/

2.40e­
04
0.061
2.52e­
04/

2.52e­
03
1.80e­
05/

1.80e­
04
Applying
Wettable­
Powders
for
Handgun
Applicators
(
ORETF)
(
5)
lawns,
parks,
recreational
areas
0.019
7.74e­
05/

7.74e­
04
5.50e06/

5.50e­
05
0.0098
4.04e­
05/

4.04e­
04
2.87e06/

2.87e­
05
Applying
Granular
with
a
Tractor
Drawn
Spreader
(
6)
sod
farms
0.004
5.56e­
06/

5.56e­
05
3.95e07/

3.95e­
06
0.0028
3.87e­
06/

3.87e­
05
2.75e07/

2.75e­
06
golf
courses
0.002
2.78e­
06/

2.78e­
05
1.98e07/

1.98e­
06
0.0014
1.94e­
06/

1.94e­
05
1.38e07/

1.38e­
06
Mixer/
Loader/
Applicator
Backpack
Sprayer
(
LCO)
(
7)
l
a
wn
s
,
g
o
l
f
c
o
u
r
s
e
s
,

ornamentals
nurseries
0.066
2.71e­
04/

2.71e­
03
1.93e­
05/

1.93e­
04
0.043
1.76e­
04/

1.76e­
03
1.25e05/

1.25e­
04
Low
Pressure
Handwand
­
Wettable
Powder
Formulations
(
LCO)
(
8)
lawns,
golf
courses,
nursery
stock
0.280
1.17e­
03/

1.17e­
02
8.30e05/

8.30e­
04
0.22
9.14e­
04/

9.14e­
03
6.50e05/

6.50e­
04
High
Pressure
Handwand
­­
(
Wettable
Powder
Formulations)
(
9)
woody
ornamentals,
conifer
nurseries.
0.068
2.79e­
04/

2.79e­
03
1.98e05/

1.98e­
04
0.045
1.84e­
04/

1.84e­
03
1.31e05/

1.31e­
04
Lawn
Handgun
(
Wettable
Powder
Formulations)
(
ORETF)
(
10)
ornamentals,
lawns,
parks
rec
areas
0.022
9.06e­
05/

9.06e­
04
6.44e­
06/

6.44e­
05
0.013
5.47e­
05/

5.47e­
04
3.89e06/

3.89e­
05
Granulars
with
a
Push
Type
Spreader
(
ORETF)
(
11)
lawns,
golf
courses,
parks,

r
e
c
r
e
a
t
iona
l
ar
e
a
s
,

ornamentals
0.006
2.54e­
05/

2.54e­
04
1.80e06/

1.80e­
05
No
Data
No
Data
No
data
Granulars
with
a
Bellygrinder
(
LCO)
(
12)
golfcourses,
pa
rk
s,
rec
areas.
0.049
1.99e­
04/

1.99e­
03
1.42e05/

1.42e­
04
0.03
1.23e­
04/

1.23e­
03
8.77e06/

8.77e­
05
a
PPE
3,4
Total
Daily
Dose
=
[
PPE
Daily
Dermal
Exposure
(
mg/
day)
*
Dermal
absorption
Factor
(
9%)+
baseline
Daily
Inhalation
Exposure
(
mg/
day)]/
Body
Weight
(
70
kg).

b
PPE
3,
4
LADD
(
mg/
kg/
day)
=
PPE
Total
Daily
Dose
(
mg/
kg/
day)
*
(
Number
of
days
exposed
per
year)
/
365
days
per
year)
*
35
years
worked/
70
year
lifetime.

C
PPE
3,
4
Total
Cancer
Risk
=
PPE
LADD
(
mg/
kg/
day)
*
(
Q
1*),
where
Q
1*
=
7.11e­
2
(
mg/
kg/
day)­
1.

PPE3
cancer
risk
includes
long
pants,
long
shirts,
gloves
and
respirator.

PPE
4
cancer
risk
includes
long
pants,
long
shirts,
double
layer,
gloves
and
respirator
Two
exposure
frequencies
were
used
for
cancer,
the
first
represented
the
maximum
number
of
applications
per
site
per
season
to
represent
private
use
(
3),
and
the
second
frequency
applied
a
factor
of
ten
to
the
first
frequency
to
represent
commercial
handlers
making
multiple
applications
per
site
per
season
(
30).
54
Table
B4:
Occupational
Handler,
Cancer
(
Q*)
Risk
from
Oxadiazon
at
Eengineering
Control
Exposure
Scenario
#
Crop
Type
Total
Eng.
Control
Daily
Dose
(
mg/
kg/
day)
a
Eng.
Control
LADDb
3/
30
days
Eng
Control
Riskc
Mixer/
Loader
Exposure
Mixing/
Loading
Wettable
Powders
for
Chemigation
Application
(
1a)
sod
farms
0.0170
6.92e­
05/
6.92e­
04
4.92E­
06/
4.92e­
05
Mixing/
Loading
Wettable
Powders
for
Groundboom
Application
(
1b)
conifer
nurseries,
woody
ornamentals
0.0026
1.05e­
05/
1.05e­
04
7.49E­
07/
7.49e­
06
herbaceous
ornamentals
0.0019
7.90e­
06/
7.90e­
05
5.62E­
07/
5.62e­
06
sod
farms
0.0038
1.58e­
05/
1.58e­
04
1.12E­
06/
1.12e­
05
golf
courses
0.0026
1.05e­
05/
1.05e­
04
7.49E­
07/
7.49e­
06
Mixing/
Loading
Wettable
Powders
for
Rights­
of­
Way
Sprayer
(
1c)
roadside
turf,
ornamentals
0.0026
1.05e­
05/
1.05e­
04
7.49E­
07/
7.49e­
06
Loading
Granular
formulations
(
2)
sod
farms,
conifers
forest
0.0002
3.09e­
073.09e­
06
2.20E­
08/
2.20e­
07
golf
course
turf,
parks,
recreational
areas
0.0001
1.54e­
07/
1.54e­
06
1.10E­
08/
1.10e­
07
woody
ornamentals
0.0001
4.63e­
07/
4.63e­
06
3.29E­
08/
3.29e­
07
Applicator
Applying
with
a
Groundboom
(
3)
sod
farms
0.0017
6.95e­
06/
6.95e­
05
4.94E­
07/
4.94e­
06
herbaceous
ornamentals
0.0009
3.47e­
06/
3.47e­
05
2.47E­
07/
2.47e­
06
golf
courses
0.0011
4.63e­
06/
4.63e­
05
3.29E­
07/
3.29e­
06
conifer
nurseries,
woody
ornamentals
0.0011
4.63e­
06/
4.63e­
05
3.29E­
07/
3.29e­
06
Applying
with
a
Rights­
of­
Way
Sprayer
(
4)
roadsides
NF
NF
NF
Applying
Wettable­
Powders
for
Handgun
Applicators
(
ORETF)
(
5)
lawns,
parks,
recreational
areas
NF
NF
NF
Applying
Granular
with
a
Tractor
Drawn
Spreader
(
6)
sod
farms
0.0019
2.56e­
06/
2.56e­
05
1.82E­
07/
1.82e­
06
golf
courses
0.0009
1.28e­
06/
1.28e­
05
9.11E­
08/
9.11e­
07
Mixer/
Loader/
Applicator
Backpack
Sprayer
(
LCO)
(
7)
lawns,
golf
courses,
ornamentals
nurseries
NF
NF
NF
Low
Pressure
Handwand
­
Wettable
Powder
Formulations
(
LCO)
(
8)
lawns,
golf
courses,
nursery
stock
NF
NF
NF
Table
B4:
Occupational
Handler,
Cancer
(
Q*)
Risk
from
Oxadiazon
at
Eengineering
Control
Exposure
Scenario
#
Crop
Type
Total
Eng.
Control
Daily
Dose
(
mg/
kg/
day)
a
Eng.
Control
LADDb
3/
30
days
Eng
Control
Riskc
55
High
Pressure
Handwand
­­
(
Wettable
Powder
Formulations)
(
9)
woody
ornamentals,
conifer
nurseries.
NF
NF
NF
Lawn
Handgun
(
Wettable
Powder
Formulations)
(
ORETF)
(
10)
ornamentals,
lawns,
parks
rec
areas
NF
NF
NF
Granulars
with
a
Push
Type
Spreader
(
ORETF)
(
11)
lawns,
golf
courses,
parks,
recreational
areas,

ornamentals
NF
NF
NF
Granulars
with
a
Bellygrinder
(
LCO)
(
12)
golfcourses,
parks,
rec
areas.
NF
NF
NF
a
Eng.
Control
Total
Daily
Dose
=[
Eng.
Control
Daily
Dermal
Exposure
(
mg/
day)*
Dermal
Absorption
Factor
(
9%)+
baseline
Daily
Inhalation
Exposure
(
mg/
day)]/
Body
Weight
(
70
kg).

b
Eng.
Control
LADD
(
mg/
kg/
day)
=
Eng.
control
Total
Daily
Dose
(
mg/
kg/
day)
*
(
Number
of
days
exposed
per
year)
/
365
days
per
year)
*
35
years
worked/
70
year
lifetime.

c
Eng.
Control
Total
Cancer
Risk
=
Eng.
Control
LADD
(
mg/
kg/
day)
*
(
Q
1*),
Q
1*
=
7.11e­
2
(
mg/
kg/
day)­
1.

NF=
Not
feasible
Two
exposure
frequencies
were
used
for
cancer,
the
first
represented
the
maximum
number
of
applications
per
site
per
season
to
represent
private
use
(
3),
and
the
second
frequency
applied
a
factor
of
ten
to
the
first
frequency
to
represent
commercial
handlers
making
multiple
applications
per
site
per
season
(
30).
56
APPENDIX
C
OCCUPATIONAL
AND
RESIDENTIAL
POST
APPLICATION
TABLES
C1
­
C4
57
Table
C1:
Occupational
Short­
and
Intermediate­
Term
Postapplication
Risks
for
Oxadiazon
Crop/
Use
Pattern
Application
Rate
(
lb
ai/
acre)
Postapplication
Activity
Transfer
Coefficienta
Short
Term
and
Intermediate
Term
Risks
Cancer
Risk
TTRb
(
ug/
cm2)
MOEc
LADDd
mg/
kg/
day
Riske
Golf
Course
Turf
4
Mow,
seed,
mechanical
weed,
aerate,
fertilize,
prune
500
2.0
(
5%
of
application
rate)
1,000
4.23e­
5
3.01e­
6
Transplant,
hand
weed
16,500
30
1.39e­
3
9.92e­
5
Sod
Farms
Mow,
scout,
mechanical
weed,
irrigate
500
1,000
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
Mow,
seed,
scout,
mechanical
weed,
aerate,
fertilize
500
1,000
4.23e­
5
3.01e­
6
a
Transfer
coefficient
from
Science
Advisory
Council
for
Exposure:
Policy
Memo
#
003
.1
"
Agricultural
Transfer
Coefficients,"
Revised
­
August
7,
2000.

b
TTR
source:
5%
of
application
rate,
"
Residential
SOP
Revised
February
2001
"
was
used
for
determination
of
MOE's.

c
MOE
=
Short­
term
NOAEL
(
12
mg/
kg/
day;
based
on
an
oral
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).

d
absorbed
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
e
Cancer
Risk
=
LADD
(
mg/
kg/
day)
x
(
Q
1*),
where
Q
1*
=
7.11e­
2
(
mg/
kg/
day)­
1.

Note:
TTR
­
Turf
Transferable
Residue
rounded
to
2.0
ug/
cm2
XXXXX
58
Table
C2.
Residential
Dermal
Postapplication
Non­
Cancer
Risks
for
Oxadiazon
Dermal
Scenarios
Application
Rate
(
lb
ai/
acre)
Exposure
Time
(
hours/
day)
Short
Term
and
Intermediate
Term
Risks
Transfer
Coefficient
(
cm2/
hr)
a
Transfer
Coefficient
(
cm2/
hr)
Irrigatedb
Transfer
Coefficient
(
cm2/
hr)

Non­
Irrigatedc
TTRd
(
ug/
cm2)

DAT
0­
1
Dermal
Dose
(
mg/
kg/
day)
e
Dermal
Dose
(
mg/
kg/
day)

Irrigatedf
Dermal
Dose
(
mg/
kg/
day)

Non­
Irrigatedg
MOEsh
MOEs
i
Irrigated
MOEsj
Non­
Irrigated
Adult
dermal
turf
contact
4
2
14500
4300
7,400
1.53
NA
1.97e­
2
3.40e­
2
NA
610
350
2.0
8.70e­
2
NA
NA
140
NA
NA
Toddler
dermal
turf
contact
2
5200
1600
2,700
0.87
NA
1.67e­
2
2.82e­
2
NA
720
430
2.0
3.12e­
2
NA
NA
390
NA
NA
Adult
walking,
playing
golf
4
500
NA
NA
2.0
6.0e­
3
NA
NA
2,000
NA
NA
Adult
push
mowing
lawn
2
500
NA
NA
2.0
3.0e­
3
NA
NA
4,000
NA
NA
a
Transfer
coefficient
from
the
Residential
SOP's
(
2/
01)
used
for
fresh
grass
b
Transfer
coefficient
from
turf
study
MRID
#
435178­
01used
for
dormant
grass
c
Transfer
coefficient
from
turf
study
MRID
#
435178­
01used
for
dormant
grass
d
TTR
source:
wettable
powder
from
turf
studies
MRID
#
435178­
01,
DAT
0­
1
residue
or
residential
SOP
(
5%
application
rate)

e
Dermal
dose
(
mg/
kg/
day)
=
TTR
(
5%
application
rate)
(

g/
cm2)
x
TC
(
from
residential
SOP,
s)
(
cm2/
hr)
x
conversion
factor
(
1
mg/
1,000

g)
x
exposure
time
(
2
or
4hrs/
day)
x
dermal
absorption
(
9
%)
/
body
weight
(
60
kg
adult
or
15
kg
toddler).

f
Dermal
dose
(
mg/
kg/
day)
irrigated
=
TTR
(
from
MRID
#
435178­
01)
(

g/
cm2)
x
TC
(
MRID
#
435178­
01)
(
cm2/
hr)
x
conversion
factor
(
1
mg/
1,000

g)
x
exposure
time
(
2
hrs/
day)
x
dermal
absorption
(
9
%)
/
body
weight
(
60
kg
adult
or
15
kg
toddler).

g
Dermal
dose
(
mg/
kg/
day)
non­
irrigated
=
TTR
(
from
MRID
#
435178­
01)
(

g/
cm2)
x
TC
(
MRID
#
435178­
01)
(
cm2/
hr)
x
conversion
factor
(
1
mg/
1,000

g)
x
exposure
time
(
2
hrs/
day)
x
dermal
absorption
(
9
%)
/
body
weight
(
60
kg
adult
or
15
kg
toddler).

h
MOE
=
Short­
term
NOAEL
(
12
mg/
kg/
day;
based
on
an
oral
study)
/
dermal
dose
(
mg/
kg/
day)

i
MOE
(
irrigated)
=
Short­
term
NOAEL
(
12
mg/
kg/
day;
based
on
an
oral
study)
/
dermal
dose
(
mg/
kg/
day)

j
MOE
(
non­
irrigated)
=
Short­
term
NOAEL
(
12
mg/
kg/
day;
based
on
an
oral
study)
/
dermal
dose
(
mg/
kg/
day)

Note:
TTR
­
Turf
Transferable
Residue
rounded
to
2.0
ug/
cm2
59
Table
C3.
Residential
Dermal
Postapplication
Cancer
Risks
for
Oxadiazon
Dermal
Scenarios
Application
Rate
(
lb
ai/
acre)
Exposure
Time
(
hours/
day)
Transfer
Coefficient
(
cm2/
hr)
a
Transfer
Coefficient
(
cm2/
hr)
Irrigatedb
Transfer
Coefficient
(
cm2/
hr)

Non­
Irrigatedc
TTRd
(
ug/
cm2)

DAT
0­
1
LADDe
mg/
kg/
day
LADDf
mg/
kg/
day
irrigated
LADDg
mg/
kg/
dayf
Non­
Irrigated
Cancerh
Cancer
Irrigatedj
Cancerj
Nonirrigated
Adult
dermal
turf
contact
4
2
14500
4300
7400
1.53
NA
6.95e­
5
1.2e­
4
NA
3.62e­
6
6.22e­
6
2.0
3.06e­
04
NA
NA
1.59e­
5
NA
NA
Toddler
dermal
turf
contact
2
5200
1600
2700
0.87
NF
NF
NF
NF
NF
NF
2.0
NF
NF
NF
NF
NF
NF
Adult
walking,
playing
golf
4
500
NA
NA
2.0
2.11e­
5
NA
NA
1.50e­
6
NA
NA
Adult
push
mowing
lawn
2
500
NA
NA
2.0
1.06e­
5
NA
NA
7.51e­
7
NA
NA
a
Transfer
coefficient
from
the
Residential
SOP's
(
2/
01)
used
for
fresh
grass
b
Transfer
coefficient
from
turf
study
MRID
#
435178­
01used
for
dormant
grass
c
Transfer
coefficient
from
turf
study
MRID
#
435178­
01used
for
dormant
grass
d
TTR
source:
wettable
powder
and
granular
turf
studies
MRID
#
435178­
01,
DAT
0­
1
residue
e
LADD
(
mg/
kg/
day)
=
TTR
(

g/
cm2)(
5%
of
application
rate)
x
TC(
residential
SOP)
(
cm2/
hr)
x
conversion
factor
(
1
mg/
1,000

g)
x
exposure
time
(
2
or
4
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
f
LADD
(
mg/
kg/
day)(
irrigated)
=
TTR
(

g/
cm2)
(
from
MRID
#
435178­
01)
x
TC
(
cm2/
hr)(
from
MRID
#
435178­
01)
x
conversion
factor
(
1
mg/
1,000

g)
x
exposure
time
(
2
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
g
LADD
(
mg/
kg/
day)(
non­
irrigated)
=
TTR
(

g/
cm2)(
from
MRID
#
435178­
01)
x
TC(
from
MRID
#
435178­
01)
(
cm2/
hr)
x
conversion
factor
(
1
mg/
1,000

g)
x
exposure
time
(
2
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
h
Cancer
Risk
=
LADD
(
mg/
kg/
day)
x
(
Q
1*),
where
Q
1*
=
7.11e­
2
(
mg/
kg/
day)­
1.

i
Cancer
Risk
(
irrigated)
=
LADD
(
mg/
kg/
day)
(
irrigated)
x
(
Q
1*),
where
Q
1*
=
7.11e­
2
(
mg/
kg/
day)­
1.

j
Cancer
Risk
(
non­
irrigated)
=
LADD
(
mg/
kg/
day)(
non­
irrigated)
x
(
Q
1*),
where
Q
1*
=
7.11e­
2
(
mg/
kg/
day)­
1.

NA=
Not
applicable
NF=
Not
Feasible
Note:
TTR
­
Turf
Transferable
Residue
rounded
to
2.0
ug/
cm2
60
Table
C4
Residential
Oral
Nondietary
Postapplication
Risks
to
Toddlers
from
"
Hand­
to­
Mouth"
and
Ingestion
Exposure
When
Reentering
Lawns
Treated
with
Granular
or
wettable
powder
Oxadiazon
Formulations
Type
of
Exposure
Application
Ratea
(
lb
ai/
acre)
Ingestion
Rate
or
Other
Assumptionsb
Short­
Term
TTRc
(

g/
cm2)

DAT
0­
1
Oral
Dosed
(
mg/
kg/
day)
MOEe
Hand
to
Mouth
Activity
4
20
cm2/
event
surface
area
of
1­
3
fingers;
20
events/
hr;
fresh
grass
5%
of
ai
dislodgeable
with
potentially
wet
hands
2.0
1.19e­
01
100
20
cm2/
event
surface
area
of
1­
3
fingers;
20
events/
hr;

2.1%
of
ai
dislodgeable
with
potentially
wet
hands
(
dormant
grass,
non­
irrigated)
1.0
5.02e­
02
240
20
cm2/
event
surface
area
of
1­
3
fingers;
20
events/
hr;

5.5%
of
ai
dislodgeable
with
potentially
wet
hands
(
dormant
grass,
irrigated)
2.5
1.31e­
01
90
Incidental
Turfgrass
Ingestion
25
cm2/
day
of
turf
20%
application
rate
(
residential
SOP)
fresh
grass
9.0
1.49e­
02
805
25
cm2/
day
of
turf
Irrigated
(
MRID
#
435178­
01)
used
for
dormant
grass
0.87
2.60e­
03
4700
25
cm2/
day
of
turf
Non­
Irrigated(
MRID
#
435178­
01)
used
for
dormant
grass
1.53
1.45e­
03
8300
Incidental
Ingestion
of
Soil
100
mg/
day
ingestion;
0.67
cm3/
gm
soil
NA
2.12e­
04
57000
a
Application
rates
represent
maximum
label
rates
from
current
EPA
registered
labels.

b
Assumptions
from
Residential
SOP's
(
February,
2001).
fresh
grass
c
TTR
source:
wettable
powder
and
granular
oxadiazon
turf
studies
MRID
Nos.
43517801.
Short­
term
risks
assessed
using
DAT
0­
1
residue
values.

d
Oral
doses
calculated
using
formulas
presented
in
the
Residential
SOPs
(
February,
2001).
Short­
term
and
intermediate­
term
doses
were
calculated
using
the
following
formulas.
Intermediate
term
doses
were
each
multiplied
by
the
estimated
fraction
of
oxadiazon
residue
remaining
on
DAT
7
after
application.

Hand­
to­
mouth
oral
dose
to
toddlers
on
the
day
of
treatment
(
mg/
kg/
day)
=
[
application
rate
(
lb
ai/
acre)
x
fraction
of
residue
dislodgeable
from
potentially
wet
hands
(
see
assumptions)
x
11.2
(
conversion
factor
to
convert
lb
ai/
acre
to

g/
cm2)]
x
median
surface
area
for
1­
3
fingers
(
20
cm2/
event)
x
hand­
to­
mouth
rate
(
ST:
20
events/
hour
)
x
exp.
time
(
2
hr/
day)
x
0.001
mg/
µ
g]
/
bw
(
15
kg
toddler).

Grass
ingestion
oral
dose
to
toddlers
on
the
day
of
treatment
(
mg/
kg/
day)
=
[
TTR
(

g/
cm2)
x
ingestion
rate
of
grass
(
25
cm2/
day)
x0.001
mg/
µ
g]
/
bw
(
15
kg
toddler).

Soil
ingestion
oral
dose
to
toddlers
on
the
day
of
treatment
(
mg/
kg/
day)
=
[(
application
rate
(
lb
ai/
acre)
x
fraction
of
residue
retained
on
uppermost
1
cm
of
soil
(
100%
or
1.0/
cm)
x
4.54E+
08

g/
lb
conversion
factor
x
2.47E­
08
acre/
cm2
conversion
factor
x
0.67
cm3/
g
soil
conversion
factor)
x
100
mg/
day
ingestion
rate
x
1.0E­
06
g/

g
conversion
factor]
/
bw
(
15
kg;

toddler).
Short
term
dose
based
residue
on
the
soil
on
day
of
application.

NA=
Not
applicable
Note:
TTR
­
Turf
Transferable
Residue
61
References
1)
Revised
Report
of
Hazard
Identification
Assessment
Review
Committee,
Dec
21,

2001.

2)
Oxadizon
Labels.

2)
Memorandum
from
J
Blondell
to
S.
Tadayon,
13
March,
2001
4)
Pesticide
Handler
Exposure
Database
Version
1.1
Surrogate
Exposure
Table
(
newly
organized)
and
printed
August
1998.

cc:
PP#
276360
RDI:
Francis
Suhre
4/
6/
2001
Timothy
Leighton
3/
21/
2001
Jeff
Evans
3/
21/
2001
S.
Tadayon:
810J:
CM#
2:
(
703)
305­
5238
62
