UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON,
D.
C.
20460
OFFICE
OF
PREVENTION,
PESTICIDES
AND
TOXIC
SUBSTANCES
July
30,
2002
CERTIFIED
MAIL
Ronald
Landis,
Ph.
D.
Landis
International
3185
Madison
Highway
PO
Box
5126
Valdosta,
GA
31603­
5126
Dear
Dr.
Landis:

Background
This
is
the
Environmental
Protection
Agency's
(
hereafter
referred
to
as
EPA
or
the
Agency)
"
Report
of
the
Food
Quality
Protection
Act
(
FQPA)
Tolerance
Reassessment
Progress
and
Risk
Management
Decision
(
TRED)
for
Diuron"
which
was
approved
on
July
30,
2002.
A
Notice
of
Availability
of
this
tolerance
reassessment
decision
will
be
published
in
the
Federal
Register
(
FR)
shortly.

The
Federal
Food,
Drug
and
Cosmetic
Act
(
FFDCA),
as
amended
by
FQPA,
requires
EPA
to
reassess
all
the
tolerances
for
registered
chemicals
in
effect
on
or
before
the
date
of
the
enactment
of
the
FQPA,
which
was
in
August
of
1996.
The
Agency
is
required
by
FQPA
to
have
2/
3
(
approximately
6,416)
of
all
tolerances
reassessed
prior
to
August
5,
2002.
In
order
to
meet
the
FQPA
tolerance
reassessment
goal,
the
tolerance
portion
of
the
reregistration
will
be
completed
prior
to
the
issuance
of
the
Reregistration
Eligibility
Decision
(
RED).
A
RED
for
diuron
will
be
completed
in
2003,
which
will
address
any
occupational
or
ecological
risk
concerns.

In
reassessing
these
tolerances,
the
Agency
must
consider,
among
other
things,
aggregate
risks
from
non­
occupational
sources
of
pesticide
exposure,
whether
there
is
increased
susceptibility
to
infants
and
children,
and
the
cumulative
effects
of
pesticides
with
a
common
mechanism
of
toxicity.
Once
a
safety
finding
has
been
made
that
aggregate
risks
are
not
of
concern,
the
tolerances
are
considered
reassessed.

Diuron
Assessment
For
diuron,
acute
and
chronic
(
non­
cancer)
dietary
food
risks
are
not
of
concern.
Drinking
water
derived
from
ground
water
is
not
a
concern
for
any
duration
or
sub­
population.
Drinking
water
derived
from
surface
water
is
not
of
concern
except
for
the
estimated
chronic
risk
in
the
flatwood
area
of
Florida
at
the
maximum
application
rate.
For
other
areas
of
Florida
where
the
citrus
application
rate
is
3.2
lbs
ai/
A
(
up
to
two
applications
per
year)
the
estimated
environmental
concentration
(
EECs)
are
30
ppb,
with
2
a
drinking
water
level
of
comparison
(
DWLOC)
of
28
ppb
for
the
most
sensitive
subpopulation,
children
1­
6.
This
represents
a
slight
exceedance
and,
given
the
protective
assumptions
in
the
dietary
assessment,
does
not
pose
a
risk
of
concern.

EPA's
risk
assessment
identified
some
areas
of
potential
concern.
These
include:
chronic
surface
drinking
water
risk
for
the
flatwood
area
of
Florida;
a
slight
exceedance
for
cancer
risk
from
food;
potential
cancer
risk
of
MCPDMU
(
N'­(
3­
chlorophenyl)­
N,
N­
dimethyl
urea)
in
water;
residential
applicator
risk
from
paint
or
stain
use;
and
aggregate
risk.

FQPA
Finding
Although
some
risks
potentially
of
concern
have
been
identified,
EPA
is
able
to
make
a
determination
of
reasonable
certainty
of
no
harm
for
diuron,
based
on
further
characterization
of
these
risks,
the
registrant's
commitment
to
mitigation
measures
designed
to
reduce
exposure
to
diuron
and
its
metabolites
in
drinking
water,
and
the
development
of
data
to
confirm
that
the
mitigation
measures
are
adequate.
Each
risk
of
potential
concern,
related
to
the
tolerance
reassessment,
with
its
characterization
and
the
mitigation
designed
to
address
the
concern,
is
discussed
below.
It
should
be
noted
that
when
the
Agency
evaluates
the
ecological
and
worker
risks
during
the
development
of
the
RED,
additional
risk
mitigation
may
be
necessary.

Cancer
Risk
from
Food
°
The
estimated
cancer
dietary
risk
associated
with
the
use
of
diuron
indicates
a
borderline
exceedance
above
1
x
10­
6
and
shows
a
lifetime
risk
estimate
of
1.68
x
10­
6
for
the
general
population
but,
is
not
of
concern.

°
The
residues
used
in
the
calculations
are
from
field
trials
conducted
at
the
highest
application
rates
and
some
processing
data
are
still
outstanding,
which
will
allow
further
refinement
of
the
risk
assessment
and
likely
lower
the
risk
estimates.

°
USDA
Pesticide
Data
Program
(
PDP)
monitoring
data
are
available
for
diuron
alone,
indicating
no
detectable
residues
of
the
parent
compound
in
citrus,
milk
and
other
sampled
commodities.

°
Conservative
assumptions
were
used
in
risk
assessment;
therefore,
the
exposure
calculation
for
cancer
dietary
risk
is
a
conservative
estimate.

Chronic
Drinking
Water
Risk
from
Surface
Water
°
Potential
chronic
drinking
water
risk
concerns
from
surface
water
are
limited
to
high
use
rate
areas
located
in
the
southern
Florida
flatwood.
In
this
area,
the
EECs
at
the
maximum
application
rate
of
6.4
lbs
ai/
A
(
9.6
lbs
ai/
A
per
year)
are
42
ppb,
with
a
DWLOC
of
28ppb.
Residue
data
to
support
the
9.6
lbs
ai/
A
per
year
rate
are
required.
The
registrant
may
provide
data
to
support
this
use
rate
or
change
the
labels
to
reflect
the
use
rate
of
6.4
lbs
ai/
A
per
year,
as
supported
by
current
residue
data.
3
°
The
registrant
is
developing
additional
information
to
refine
the
conservative
percent
crop
area
(
PCA)
factor
(
87%)
used
in
the
drinking
water
assessment.
This
research
will
include
spatial
integration
of
information
on
surface
water
sources
for
drinking
water
in
the
high
use
rate
areas
relative
to
citrus
production
and
soil
runoff
potential.

°
Existing
surface
water
monitoring
data
for
diuron
from
Florida
and
California
show
a
relatively
high
percentage
of
detections,
but
concentrations
generally
one
to
two
orders
of
magnitude
less
than
modeled
values.

°
The
registrants
have
agreed
to
rate
reductions,
reductions
in
the
number
of
applications
per
year,
and
increases
in
the
intervals
between
applications
as
outlined
in
Table
1.

°
Additional
targeted
drinking
water
monitoring
will
be
required
to
fully
characterize
drinking
water
risk
of
diuron
and
its
metabolites.

Potential
Cancer
Risk
of
the
MCPDMU
Metabolite
in
Water
°
In
water
only,
diuron
partially
degrades
to
another
chemical,
MCPDMU
(
N'­(
3­
chlorophenyl)­
N,
N­
dimethyl
urea).

°
The
cancer
estimate
for
MCPDMU
is
derived
by
analogy
to
a
similar
compound,
monuron,
and
represents
worst
case.
It
is
possible
that
MCPDMU
is
less
toxic
than
monuron;
it
is
unlikely
that
it
is
more
toxic.
Monuron
produces
kidney
and
liver
tumors
in
male
rats.
The
estimated
risk
for
monuron
is
based
on
a
Q*
of
1.52
x
10­
2
(
mg/
kg/
day)­
1.

°
Since
there
is
potential
for
MCPDMU
to
occur
in
water,
the
Agency
considered
possible
exposures
to
MCPDMU
from
ingestion
of
catfish,
as
well
as
from
drinking
water.

°
For
chronic
risk,
the
EECs
for
surface
water
from
PRZM/
EXAMS
(
42
ppb)
exceeds
the
drinking
water
level
of
comparison
(
DWLOC)
of
28
ppb
for
the
most
sensitive
population
subgroup
(
children
1
­
6),
in
the
Flatwood
area
of
Florida,
at
the
highest
application
rate.

°
Residue
data
to
support
the
9.6
lbs
ai/
A
per
year
rate
for
citrus
are
required.
The
registrant
may
provide
data
to
support
this
use
rate
or
change
the
labels
to
reflect
the
use
rate
of
6.4
lbs
ai/
A
per
year,
as
supported
by
current
residue
data.

°
Additional
data
are
being
required
about
the
behavior
and
fate
of
MCPDMU
in
drinking
water.
This
information
will
permit
refinement
of
the
drinking
water
assessment.

°
The
reductions
in
application
rate
and
the
number
of
applications
per
year
shown
in
Table
1
will
also
reduce
exposure
to
diuron
metabolites.

°
If
the
refined
data
and
refined
assessment
still
show
drinking
water
concerns,
drinking
water
monitoring
and/
or
toxicity
data
on
MCPDMU
will
be
required.
4
5
Residential
Cancer
Risk
from
Paint
or
Stain
Use
°
Calculated
cancer
risk
to
adult
applicators
using
diuron
treated
paints
or
stains
applied
with
airless
paint
sprayer
or
paint
brush
is
estimated
to
range
from
9.5
x
10­
7
to
3.4
x
10­
6,
depending
on
the
exposure
assumptions
used,
application
method
employed
and
the
amount
applied.

°
Post­
application
exposure
to
children
is
expected
to
be
minimal
as
indicated
in
modeled
estimates
of
inhaled
diuron
from
a
screening­
level
inhalation
assessment
combined
diuron's
low
vapor
pressure.

°
The
assessment
assumes
two
gallons
for
paints
to
five
gallons
for
stains
applied
with
a
brush
per
day
or
fifteen
gallons
applied
per
day
with
an
airless
sprayer,
2
applications
per
year,
50
years
of
use
over
a
70
year
lifetime,
and
a
high­
end
dermal
absorption
factor
of
4%
calculated
from
submitted
studies.

°
Less
than
5%
of
all
paint
contains
diuron.
Therefore,
it
is
unlikely
that
a
homeowner
would
apply
2
to
5
gallons
of
paint
containing
diuron
two
times
per
year
for
50
years.

Aggregate
Risk
The
aggregate
risk
assessment
for
diuron
examines
the
combined
risk
from
exposure
through
food,
drinking
water,
and
residential
use.

°
There
are
no
adverse
effects
expected
from
a
single
exposure
to
diuron;
therefore,
an
acute
risk
assessment
was
not
conducted.
Short­
term
aggregate
risks
from
food,
residential
inhalation,
and
drinking
water
are
not
of
concern.

°
Estimated
aggregate
chronic
risk
(
noncancer)
concentrations
of
diuron
and
its
metabolites
in
surface
water
slightly
exceed
the
chronic
DWLOC
in
the
Flatwood
area
of
Florida.
Because
field
trial
residue
levels
(
from
maximum
labeled
rates)
were
used
in
the
assessments,
dietary
risks
are
high
end
estimates
and
may
be
refined
further.

°
An
aggregate
cancer
estimate
has
not
been
calculated
since
conservative
assumptions
were
used
in
both
the
dietary
and
drinking
water
assessments.
Thus,
aggregation
of
these
assessments
would
result
in
an
even
more
conservative
expression
of
risk.

°
Dietary
risk
estimates
can
be
further
refined
with
processing
data
and
monitoring
data
that
accounts
for
diuron
and
its
metabolites.

°
Additional
targeted
drinking
water
monitoring
will
be
required
to
fully
characterize
drinking
water
risk
of
diuron
and
its
metabolites.

°
Because
of
the
low
percent
of
paint
containing
diuron,
exposure
to
home
applicators
is
not
likely
to
be
a
significant
contributor
to
aggregate
risk.
6
7
Mitigation
and
Best
Management
Practices
The
registrant
has
agreed
to
the
following
measures
to
reduce
exposure
to
diuron:

°
Best
Management
Practices
for
managing
spray
drift.
°
No
aerial
applications
except
for
rights­
of­
way,
alfalfa,
and
cotton.
°
Eliminate
use
in
areas
with
muck
soils.
°
Rate
reductions,
increased
application
intervals,
and
limits
on
the
number
of
application
as
noted
below
in
Table
1.
°
Revise
the
product
labels
consistent
with
the
changes
outlined
in
the
Residue
Chemistry
Chapter
and
submits
the
required
residue
data
to
support
the
9.6
lbs
ai/
A
per
year
rate
for
citrus.
8
Table
1:
Revised
Application
Parameters
Crop
Current
Maximum
Application
Rate
Current
Number
of
Applications/
Retreatment
Interval
Revised
Maximum
Application
Rate
Revised
Number
of
Applications/
Retreatment
Interval
Right­
of
Way
12
lb
ai/
A
(
typically
18
lb
ai/
A
year)
Not
Restricted
(
Typically
2)
12
lb
ai/
A
per
year
2
,
with
a
90­
day
retreatment
interval
Citrus
(
other
than
Flatwood
area)
3.2
lb
ai/
A
No
Limit
(
1.6
­
3.2
lb/
A
per
application
to
max
of
6.4
lb/
A
per
year)
3.2
lb
ai/
A
(
6.4
lb
ai/
A
per
year)
2
,
with
a
60­
day
retreatment
interval
(
Trees
<
4
years)

2
,
with
a
80­
day
retreatment
interval
(
Trees
>
4
years)

Citrus
(
Flatwood
area)*
6.4
lb
ai/
A
(
9.6
lb
ai/
A
per
year)
No
Limit
(
1.6
­
6.4
lb/
A
per
application
to
max
of
9.6
lb/
A
per
year)
6.4
lb
ai/
A
(
9.6
lb
ai/
A
per
year)
2
,
with
a
60­
day
retreatment
interval
(
Trees
<
4
years)

2
,
with
a
80­
day
retreatment
interval
(
Trees
>
4
years)

Apple
3.2
lb
ai/
A
1­
2
(
1.6
­
3.2
lb/
A
to
max
of
3.2
lb/
A
per
year)
3.2
lb
ai/
A
per
year
1­
2
(
1.6
­
3.2
lb/
A
to
max
of
3.2
lb
ai/
A
per
year),
with
a
90­
day
retreatment
interval
Alfalfa
3.2
lb
ai/
A
1
app./
year
2.4
lb
ai/
A
per
year
1
Cotton
2.2
lb
ai/
A
Not
Restricted
Preplant/
Pre­
emergence:
(
0.8
­
1.6
lb
ai/
A)
3,
with
total
ai
per
season
limited
to
0.8
lb
ai/
A
on
coarse
soils,
1.5
lb
ai/
A
on
medium
soils
and
2.2
lb
ai/
A
on
fine
soils,
with
a
21­
day
retreatment
interval
Post­
emergence:
(
0.8
­
1.2
lb
ai/
A,
depending
upon
soil
texture)

Grapes
9.6
lb
ai/
A
2
4
lb
ai/
A
(
8
lb
ai/
A
per
year)
2,
with
a
90­
day
retreatment
interval
*
Residue
data
to
support
the
9.6
lbs
ai/
A
per
year
rate
is
required,
or
labels
modified
to
reflect
a
maximum
of
6.4
lbs
ai/
A
applied
per
year.
9
Cumulative
Assessment
FQPA
requires
that
EPA
consider
"
available
information"
concerning
the
cumulative
effects
of
a
particular
pesticide's
residues
and
"
other
substances
that
have
a
common
mechanism
of
toxicity."
The
reason
for
considering
other
substances
is
because
of
the
possibility
that
low­
level
exposures
to
multiple
chemical
substances
that
cause
a
common
toxic
effect
by
a
common
mechanism
could
lead
to
the
same
adverse
health
effect,
as
would
a
higher
level
of
exposure
to
any
of
the
other
substances
individually.
EPA
did
not
perform
a
cumulative
risk
assessment
as
part
of
this
review
of
diuron,
because
the
Agency
has
not
determined
that
there
are
any
other
chemical
substances
that
have
a
mechanism
of
toxicity
common
with
that
of
diuron.
If
EPA
identifies
other
substances
that
share
a
common
mechanism
of
toxicity
with
diuron,
then
a
cumulative
risk
assessment
will
be
conducted
that
includes
diuron
once
the
final
framework
EPA
will
use
for
conducting
cumulative
risk
assessments
is
available.
Further,
EPA
is
in
the
process
of
developing
criteria
for
characterizing
and
testing
endocrine
disrupting
chemicals
and
plans
to
implement
an
Endocrine
Disruptor
Screening
Program.
Diuron
will
be
reevaluated
at
that
time
and
additional
studies
may
be
required.

Tolerance
Reassessment
The
Agency's
tolerance
reassessment
for
the
pesticide
diuron,
has
been
discussed
with
interested
stakeholders
and
a
closure
call
will
be
held
prior
to
issuance
of
the
RED.
In
addition,
both
the
human
health
effects
and
the
environmental
risk
assessments
are
summarized
in
the
enclosed
Overview
of
the
Diuron
Risk
Assessment
document.
The
risk
assessments
and
other
documents
pertaining
to
the
diuron
tolerance
reassessment
decision
are
available
on
the
Internet
at
http://
www.
epa.
gov/
pesticides/
reregistration/
status.
htm
and
are
in
the
public
docket
for
viewing.
As
mentioned
previously,
other
risks
posed
by
diuron
will
be
addressed
through
the
reregistration
process
in
2003.

The
Agency
has
reassessed
all
81
existing,
permanent
tolerances
for
diuron
and
can
make
a
FQPA
safety
determination.
In
addition,
two
new
tolerances
are
proposed
for
use
on
prickly
pear
(
0.05
ppm),
and
spearmint
(
1.5
ppm).
The
Agency
has
sufficient
residue
data
for
reassessing
the
tolerances
for
diuron
and
is
requiring
additional
confirmatory
data
for
alfalfa
forage;
globe
artichokes;
barley
hay;
citrus
(
9.6
lbs
ai/
A
per
year
rate),
cotton
gin
byproducts;
field
corn
aspirated
grain
fractions,
forage
and
stover;
sweet
corn,
stover;
sweet
corn,
forage;
filberts;
grass
forage,
hay
seed
screenings
and
straw;
lemon;
pear;
oat
forage,
hay;
olive;
field
pea
vines
and
hay;
sorghum
aspirated
grain,
fractions,
stover,
and
forage;
and
wheat
forage
and
hay.
For
commodities
that
require
additional
residue
data,
the
current
tolerance
value
is
protective
of
human
health
and
will
continue
to
be
used
for
enforcement
purposes
until
new
data
are
received.
If
the
new
data
indicate
that
adjustments
to
tolerances
are
warranted,
they
will
be
adjusted
at
that
time.
Anticipated
residues
for
all
commodities
were
calculated
from
field
trial
data
and
subsequently
utilized
to
estimate
the
dietary
exposure
to
diuron.
Dietary
risks
from
exposure
do
not
exceed
the
Agency's
level
of
concern.
Final
tolerances
for
most
crops
are
being
proposed
as
part
of
this
tolerance
reassessment.
Additional
tolerances
may
be
revised
once
the
confirmatory
field
trial
data
have
been
submitted
to
and
reviewed
by
the
Agency.
In
addition,
processing
data
for
field
corn
and
olives
and
a
metabolism
study
in
fish
are
required.

Table
2.
Tolerance
Reassessment
Summary
for
Diuron
10
Commodity
Established
Tolerance
(
ppm)
1
Reassessed
Tolerance
(
ppm)
2
Comment
Correct
Commodity
Definition
Tolerances
Listed
Under
40
CFR
§
180.106(
a)

Alfalfa
2
2/(
TBD3)
[
Alfalfa,
forage]

2.0
[
Alfalfa,
hay]

Apples
1
0.10
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.10
ppm.
[
Apple]

Artichokes
1
1/(
TBD)
[
Artichoke,
globe]

Asparagus
7
7.0
Treatment
of
asparagus
is
restricted
to
early
season,
prior
to
the
appearance
of
asparagus
spears.

Bananas
0.1
0.05
This
tolerance
should
be
reclassified
under
180.106(
c),
as
use
of
diuron
on
banana
will
be
restricted
to
HI.
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.05
ppm.
[
Banana]

Barley,
grain
1
0.20
These
tolerances
should
be
reclassified
under
180.106(
c),
as
use
of
diuron
on
barley
is
restricted
to
western
OR
and
WA.
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.20
ppm
for
barley,
grain;
and
to
1.5
ppm
for
barley,
straw.
Barley,
hay
2
2/(
TBD)

Barley,
straw
(
2)
6
1.5
Birdsfoot
trefoil,
forage
2
0.10
These
tolerances
should
be
reclassified
under
180.106(
c),
as
use
of
diuron
on
trefoil
is
restricted
to
western
OR.
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.10
ppm
for
birdsfoot
trefoil,
forage
and
to
0.15
ppm
for
birdsfoot
trefoil,
hay.
Birdsfoot
trefoil,
hay
2
0.15
Blackberries
1
Reassign;
0.10
The
established
tolerances
for
blackberries,
blueberries,
boysenberries,
currants,
dewberries,
gooseberries,
huckleberries,
loganberries,
and
raspberries
should
be
revoked
concomitant
with
the
establishment
of
a
tolerance
for:
The
available
data
indicate
that
these
tolerances
should
be
reduced
to
0.10
ppm.
[
Berry
Group].
Blueberries
1
Boysenberries
1
Currants
1
Dewberries
1
Gooseberries
1
Huckleberries
1
Loganberries
1
Raspberries
1
Commodity
Established
Tolerance
(
ppm)
1
Reassessed
Tolerance
(
ppm)
2
Comment
Correct
Commodity
Definition
11
Cattle,
fat
1
16
Cattle,
meat
1
16
Cattle,
meat
byproducts
1
16
Citrus
fruits
1
1/(
TBD3,
6)
[
Fruit,
citrus,
group]

Citrus
pulp,
dried
4
4/(
TBD)
[
Citrus,
dried
pulp]

Clover,
forage
2
0.10
These
tolerances
should
be
reclassified
under
180.106(
c),
as
use
of
diuron
on
clover
is
restricted
to
western
OR.
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.10
ppm
for
clover,
forage
and
to
1
ppm
for
clover,
hay.
Clover,
hay
2
1
Corn
in
grain
or
ear
form
(
including
sweet
corn,
field
corn,
popcorn)
1
0.10
Concomitant
with
the
reassignment
of
this
tolerance,
a
separate
tolerance
should
be
established
for
[
Corn,
field,
grain].
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.10
ppm.

1
0.10
Concomitant
with
the
reassignment
of
this
tolerance,
a
separate
tolerance
should
be
established
for
[
Corn,
pop,
grain].
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.10
ppm.

1
0.10
Concomitant
with
the
reassignment
of
this
tolerance,
a
separate
tolerance
should
be
established
for
[
Corn,
sweet,
grain].
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.10
ppm.

1
0.10
Concomitant
with
the
reassignment
of
this
tolerance,
a
separate
tolerance
should
be
established
for
[
Corn,
field,
ear].
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.10
ppm.

1
0.10
Concomitant
with
the
reassignment
of
this
tolerance,
a
separate
tolerance
should
be
established
for
[
Corn,
pop
ear].
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.10
ppm.
Commodity
Established
Tolerance
(
ppm)
1
Reassessed
Tolerance
(
ppm)
2
Comment
Correct
Commodity
Definition
12
1
0.10
Concomitant
with
the
reassignment
of
this
tolerance,
a
separate
tolerance
should
be
established
for
[
Corn,
sweet
ear].
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.10
ppm.

Corn,
sweet,
fodder
2
Revoke
There
are
no
registered
uses
of
diuron
on
sweet
corn.
Corn,
sweet,
forage
2
Corn,
field
fodder
2
2/(
TBD)
This
tolerance
was
inadvertently
omitted
from
the
1/
14/
98
Final
Rule
technical
amendment
consolidating
40
CFR
parts
185­
186
to
40
CFR
part
180.
This
action
will
reinstate
this
tolerance
to
40
CFR
part
180.106.
[
Corn,
field,
stover]

Corn,
pop,
fodder
2
2/(
TBD)
This
tolerance
was
inadvertently
omitted
from
the
1/
14/
98
Final
Rule
technical
amendment
consolidating
40
CFR
parts
185­
186
to
40
CFR
part
180.
This
action
will
reinstate
this
tolerance
to
40
CFR
part
180.106.
[
Corn,
pop,
stover]

Corn,
field
forage
2
2/(
TBD)
This
tolerance
was
inadvertently
omitted
from
the
1/
14/
98
Final
Rule
technical
amendment
consolidating
40
CFR
parts
185­
186
to
40
CFR
part
180.
This
action
will
reinstate
this
tolerance
to
40
CFR
part
180.106.
[
Corn,
field,
forage]

Corn,
pop,
forage
2
2/(
TBD)
This
tolerance
was
inadvertently
omitted
from
the
1/
14/
98
Final
Rule
technical
amendment
consolidating
40
CFR
parts
185­
186
to
40
CFR
part
180.
This
action
will
reinstate
this
tolerance
to
40
CFR
part
180.106.
[
Corn,
pop,
forage]

Cottonseed
1
0.20
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.20
ppm.
[
Cotton,
undelinted
seed]

Goats,
fat
1
16
[
Goat,
fat]

Goats,
meat
1
16
[
Goat,
meat]

Goats,
meat
byproducts
1
16
[
Goat,
meat
byproducts]

Grapes
1
0.05
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.05
ppm.
[
Grape]
Commodity
Established
Tolerance
(
ppm)
1
Reassessed
Tolerance
(
ppm)
2
Comment
Correct
Commodity
Definition
13
Grass
crops
(
other
than
Bermuda
grass)
2
2/(
TBD)
[
Grass,
forage,
except
Bermuda
grass]

Grass,
hay
(
other
than
Bermuda
grass
hay)
2
2/(
TBD)
[
Grass,
hay,
except
Bermuda
grass]

Hogs,
fat
1
16
[
Hog,
fat]

Hogs,
meat
1
16
[
Hog,
meat]

Hogs,
meat
byproducts
1
16
[
Hog,
meat
byproducts]

Horses,
fat
1
16
[
Horse,
fat]

Horses,
meat
1
16
[
Horse,
meat]

Horses,
meat
byproducts
1
16
[
Horse,
meat
byproducts]

Nuts
0.1
0.1/(
TBD)
Concomitant
with
the
reassignment
of
this
tolerance,
separate
a
separate
tolerance
should
be
established
for
[
Filbert
].

0.05
Concomitant
with
the
reassignment
of
this
tolerance,
separate
a
separate
tolerance
should
be
established
for
[
Nut,
macadamia].
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.05
ppm.

0.05
Concomitant
with
the
reassignment
of
this
tolerance,
separate
a
separate
tolerance
should
be
established
for
[
Pecan].
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.05
ppm.

0.05
Concomitant
with
the
reassignment
of
this
tolerance,
separate
a
separate
tolerance
should
be
established
for
[
Walnut].
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.05
ppm.

Oats,
forage
2
2/(
TBD)
These
tolerances
should
be
reclassified
under
180.106(
c),
as
use
of
diuron
on
oats
is
restricted
to
ID,
OR,
and
WA.
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.10
ppm
for
oats,
grain;
and
to
1.5
ppm
for
oats,
straw.
Oats,
grain
1
0.10
Oats,
hay
2
2/(
TBD)

Oats,
straw
2
1.5
Olives
1
1/(
TBD)
[
Olive]

Papayas
0.5
0.50
[
Papayas]
Commodity
Established
Tolerance
(
ppm)
1
Reassessed
Tolerance
(
ppm)
2
Comment
Correct
Commodity
Definition
14
Peaches
0.1
0.10
[
Peach]

Pears
1
1/(
TBD)
[
Pear]

Peas
1
0.10
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.10
ppm.
[
Pea,
field,
seed]

Peas,
forage
2
2/(
TBD)
[
Pea,
field,
vines]

Peas,
hay
2
2/(
TBD)
[
Pea,
field,
hay]

Peppermint,
hay
2
1.5
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
1.5
ppm.
[
Peppermint,
tops]

Pineapple
1
0.10
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.10
ppm.

Potatoes
1
Revoke
There
are
no
registered
uses
of
diuron
on
potatoes.

Rye,
forage
2
Revoke
There
are
no
registered
uses
of
diuron
on
rye.
Rye,
grain
1
Rye,
hay
2
Rye,
straw
2
Sheep,
fat
1
16
Sheep,
meat
1
16
Sheep,
meat
byproducts
1
16
Sorghum,
fodder
2
2/(
TBD)
[
Sorghum,
grain,
stover]

Sorghum,
forage
2
2/(
TBD)
[
Sorghum,
grain,
forage]

Sorghum,
grain
1
0.50
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.50
ppm.
[
Sorghum,
grain,
grain]

Sugarcane
1
0.20
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.20
ppm.

Vetch,
forage
2
0.10
These
tolerances
should
be
reclassified
under
180.106(
c),
as
use
of
diuron
on
vetch
is
restricted
to
ID,
OR,
and
WA.
The
available
data
indicate
that
these
tolerances
should
be
reduced
to
0.10
ppm
for
vetch,
forage
and
to
1.5
ppm
for
vetch,
hay.
Vetch,
hay
2
1.5
Vetch,
seed
1
Revoke
No
longer
considered
a
significant
livestock
feed
item.
Commodity
Established
Tolerance
(
ppm)
1
Reassessed
Tolerance
(
ppm)
2
Comment
Correct
Commodity
Definition
15
Wheat,
forage
2
2/(
TBD)

Wheat,
grain
1
0.50
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
0.50
ppm.

Wheat,
hay
2
2/(
TBD)

Wheat,
straw
2
1.5
The
available
data
indicate
that
the
tolerance
should
be
reduced
to
1.5
ppm.

Tolerance
Listed
Under
40
CFR
§
180.106(
b)

Catfish
fillets
2.04
2.0
Expiration
date
of
06/
30/
03
[
Catfish]

Tolerances
To
Be
Proposed
Under
40
CFR
§
180.106(
a)

Aspirated
grain
fractions
N/
A
5.0
Barley,
bran
N/
A
0.7
Citrus,
oil
N/
A
TBD
Cotton,
gin
byproducts
N/
A
TBD
Eggs
N/
A
TBD
Grass,
seed
screenings
N/
A
TBD
Grass,
straw
N/
A
TBD
Milk
N/
A
TBD
Pineapple,
process
residue
N/
A
0.40
Poultry,
meat
byproducts
N/
A
TBD
Prickly
pear
N/
A
0.05
Spearmint
N/
A
1.5
Sugarcane,
molasses
N/
A
0.70
Wheat,
bran
N/
A
0.70
1.
Expressed
as
diuron
per
se,
unless
otherwise
stated.

2.
To
be
expressed
as
the
combined
residues
of
diuron
and
its
metabolites
convertible
to
3,4­
DCA,
expressed
as
diuron.
The
residues
of
3,4­
DCA
are
low
but
diuron
residues
are
converted
to
3,4­
DCA
for
the
tolerance
expression
based
on
the
assumption
that
the
metabolites
would
not
be
any
more
toxic
than
diuron
and
the
consideration
that
the
analytical
methods
used
to
collect
the
field
trial
data
are
not
capable
of
measuring
each
metabolite
individually.
The
reassessed
tolerances
are
contingent
upon
the
recommended
label
revisions
outlined
in
Table
B
of
the
Residue
Chemistry
Chapter
16
For
The
Diuron
Reregistration
Eligibility
Decision
(
RED)
Document,
dated
7/
29/
2001.

3.
TBD
=
To
be
determined.
These
commodities
were
included
in
the
dietary
risk
assessment
using
the
Current
Tolerance
level.
Additional
confirmatory
field
trial
residue
data
are
required;
therefore,
the
final
tolerance
may
be
revised.

4.
Expressed
as
combined
residues
of
diuron
and
its
metabolites
convertible
to
3,4­
DCA.

5.
Feeding
study
data
have
been
submitted
to
reassess
the
established
tolerances
for
the
fat,
meat,
and
meat
byproducts
of
cattle,
goats,
hogs,
horses,
and
sheep.
Residue
data
are
not
available
for
several
potential
feed
items.
If
the
maximum
dietary
burden
does
not
increase
when
recalculated
from
all
potential
feed
items
after
acceptable
field
trial
data
are
submitted
then
the
established
tolerances
for
residues
in
fat,
meat,
and
meat
byproducts
of
cattle,
goats,
hogs,
horses,
and
sheep
can
be
lowered.

6.
Residue
data
to
support
the
9.6
lbs
ai/
A
per
year
rate
on
citrus
are
required.
The
registrant
may
provide
data
to
support
this
use
rate
or
change
the
labels
to
reflect
the
use
rate
of
6.4
lbs
ai/
A
per
year,
as
supported
by
current
residue
data.
17
No
maximum
residue
limits
(
MRLs)
for
diuron
have
been
established
by
Codex
for
any
agricultural
commodity.

If
you
have
questions
on
this
document,
please
contact
the
Chemical
Review
Manager,
Diane
Isbell,
at
(
703)
308­
8154.

Sincerely,

Lois
A.
Rossi,
Director
Special
Review
and
Reregistration
Division
Enclosure:

Overview
of
the
Diuron
Risk
Assessment
Diuron
Summary
