Document ID: EPA-HQ-OPP-2004-0162-0031
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2005-12-23T05:00Z

Page
1
of
10
UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON,
D.
C.
20460
OFFICE
OF
PREVENTION,
PESTICIDES
AND
TOXIC
SUBSTANCES
PC
Code:
103001
DP
Barcodes:
D305591
MEMORANDUM
August
16,
2005
Subject:
EFED
Response
to
"
Error
Only"
and
Public
Comments
for
the
Napropamide
RED
To:
Susan
Lewis,
Branch
Chief,/
Demson
Fuller,
Chemical
Review
Manager
Reregistration
Branch
I
Special
Review
and
Reregistration
Division
(
7508C)

From:
James
Breithaupt,
Agronomist
Shannon
Borges,
Biologist
Environmental
Risk
Branch
II
Environmental
Fate
and
Effects
Division
(
7507C)

Through:
Tom
Bailey,
Ph.
D,
Chief,
ERB
II,
Environmental
Fate
and
Effects
Division
(
7507C)

EFED
is
responding
to
"
Error­
Only"
and
public
comments
for
the
napropamide
RED.
Many
of
the
comments
were
substantive
and
led
to
changes
in
the
RED.
Some
of
these
included
application
rates,
modeling
inputs,
and
submission
of
additional
data.

Registrant
Comment
Napropamide
is
a
pre­
emergent
herbicide,
generally
applied
to
bare
ground.
The
product
works
by
disrupting
the
growth
process
during
germination
and
therefore
soil
incorporation
or
wateringin
is
recommended.
To
be
effective,
napropamide
must
reach
the
zone
of
weed
seed
germination,
which
is
typically
2
to
4
inches
below
the
soil
surface.
All
the
product
labels
bear
wording
recommending
either
mechanical
incorporation
or
incorporation
through
irrigation.

Response
to
Registrant
The
registrant
is
correct
in
noting
that
the
labels
require
incorporation
to
2­
4
inches
(
5.08
to
10.16
cm)
of
soil
depth
following
application.
However,
the
required
time
until
incorporation
ranges
from
24
hours
to
3
weeks,
and
significant
rainfall
leading
to
runoff
and
erosion
could
occur
Page
2
of
10
in
that
time
frame.
Therefore,
runoff
prior
to
proper
incorporation
could
occur
and
EFED
modeled
an
incorporation
depth
of
0.5
cm
for
all
uses.

Registrant
Comment
The
cancelled
WP
formulation
was
registered
for
use
on
food
crops
at
the
6
lb
ai/
A
rate,
which
is
referenced
in
many
of
the
EPA
documents.
This
use
rate
is
not
found
on
the
current
product
labels
for
food
crop
uses,
only
for
turf
and
ornamental
uses.

Response
to
Registrant
According
to
the
Use
Closure
Memorandum
dated
4/
29/
04,
the
registrant
intends
to
support
all
currently
registered
products
EXCEPT
DEVRINOL
50
WP
Selective
(
EPA
Reg.
No.
70506­
26),
DEVRINOL
50WP
Ornamental
(
EPA
Reg.
No.
70506­
29),
and
DEVRINOL
(
EPA
Reg.
No.
70506­
32).
EFED
removed
all
references
to
the
50
WP
formulation
in
the
current
reregistration
document.
However,
the
50WP
label
is
not
the
only
one
with
an
application
rate
of
6
lbs
ai/
A.
The
label
with
Reg.
No.
70506­
33
contains
a
one­
time
application
rate
of
6
lbs
ai/
A
to
fruit,
nut,
and
citrus
crops.
Therefore,
EFED
did
assess
the
use
of
70506­
33.

Registrant
Comment
Many
of
the
risk
assessment
documents
use
the
scenario
of
two
applications
for
some
crops.
However,
a
second
application
is
permitted
only
for
certain
crops
in
the
Western
region
(
see
label
for
Devrinol
50­
DF
Selective
(
70506­
36)
for
a
map
of
which
states
this
includes).

Response
to
Registrant
EFED
modeled
the
application
of
two
applications
for
all
of
the
orchard
and
vineyard
scenarios
because
label
70506­
36
does
allow
application
of
up
to
8
lbs
ai/
A
in
split
applications.
The
only
orchard
crops
to
which
the
label
does
not
allow
two
applications
in
all
geographic
regions
of
the
U.
S
are
kiwifruit
and
olives.
EFED
has
PRZM­
EXAMS
scenarios
for
almost
all
listed
orchard
and
vineyard
crops
to
which
two
applications
can
be
made
in
all
regions.

Registrant
Comment
In
instances
where
more
than
one
application
is
permitted,
the
interval
of
7
days
between
applications
(
the
input
parameter
used
by
EPA
in
risk
assessments)
does
not
reflect
agricultural
practices
for
herbicides.
An
interval
of
90
days
would
be
considered
more
representative
for
this
herbicide.
Page
3
of
10
Response
to
Registrant
EFED
modeled
an
application
interval
of
60
days
for
all
scenarios
with
multiple
applications.
While
90
days
may
be
more
representative,
the
PRZM­
EXAMS
PE­
4
shell
would
not
accommodate
that
interval
in
some
scenarios
because
the
modeled
dates
occurred
in
two
different
crop
years.
The
use
of
60
days
is
in
accordance
with
labels
for
napropamide
applied
to
turf
and
ornamentals.
EFED
also
believes
that
the
60­
day
interval
is
appropriate
for
the
other
crops
with
multiple
applications.

Registrant
Comment
The
vast
majority
of
the
agricultural
uses
(
with
the
exception
of
turf,
mint
and
cranberries),
receive
band
treatments
such
that
the
actual
amount
of
product
applied
to
the
field
(
vs.
broadcast)
is
lower
than
a
calculated
per
acre
rate.
In
band
treatments,
the
product
is
applied
to
the
area
directly
under
the
tree
(
usually
a
4­
8
foot
wide
band)
and
not
in
the
aisles
(
or
middle
rows).
Compared
to
broadcast
methods,
this
application
scenario
results
in
only
about
1/
3
of
an
acre
receiving
treatment.
Although
Devrinol
may
be
applied
to
any
crop
as
a
broadcast
treatment,
this
method
is
not
economical
for
growers
and
is
used
less
than
10%
of
the
time
in
favor
of
band
treatments.

Response
to
Registrant
EFED
realizes
that
in
many
situations
pre­
emergence
herbicides
such
as
napropamide
may
be
banded
instead
of
broadcasted
to
an
entire
field.
Therefore,
EFED
modeled
potential
exposure
to
plant
and
animals
using
both
the
maximum
labeled
rate(
s)
and
the
"
typical"
banded
rates.

Registrant
Comment
The
cranberry
maximum
use
rate
is
9
lb
ai/
A.
Although
a
rate
of
15
lb
ai/
A
appears
on
the
label
(
Devrinol
10­
G),
it
is
registered
for
use
only
in
WA
and
OR,
and
only
if
the
bog
soil
type
is
muck
soil.
There
are
an
estimated
34,000
acres
of
cranberries
grown
in
the
US
[
13,000
in
WI,
15,000
in
MA,
3,000
in
NJ,
1,000
in
WA
and
1500
in
OR;
USDA,
NASS,
The
Cranberry
Institute].
The
cranberry
acres
in
WA,
the
only
region
of
the
US
with
muck
soils,
represent
only
3%
of
the
total
cranberry
acres,
and
not
all
of
those
acres
have
muck
soils.
The
use
rates
in
that
region
are
in
fact
closer
to
6
to
7
lb
ai/
A
and
not
15
as
used
in
the
EFED
risk
assessments
[
personal
communication,
Delmer
Robison,
Western
Growers
Supply,
Bandon,
OR].

Response
to
Registrant
To
model
aquatic
exposure
from
applied
pesticides
in
cranberry
production,
EFED
uses
a
modified
version
of
the
Interim
Rice
Model.
The
standard
practice
is
to
model
the
maximum
application
rate
applied
to
any
scenario
and
crop
because
the
label
allows
that
rate.
Page
4
of
10
Registrant
Comment
In
the
EFED
Risk
Assessment
for
the
Napropamide
Reregistration
Eligibility
Document
(
page
10),
information
from
the
National
Agriculture
Statistics
Service
(
NASS)
was
cited
regarding
napropamide
usage
in
the
US.
NASS
reported
that
napropamide
was
used
on
treated
acres
for
the
following
crops
(
representing
75%
of
the
napropamide
use
in
1997):

Tomatoes
 
23.5
%
Tobacco
 
20%
Cranberries
11.8%
Hot
Peppers
10.2%
Strawberries
 
8.9%

NASS
reports
that
448,000
lbs
ai
were
applied
in
1997.
UPI
is
providing
more
detailed
sales
and
use
figures.
Due
to
the
confidentiality
of
the
following
information,
this
commercial
and
financial
information
has
been
removed
to
a
confidential
appendix
and
is
cited
by
CROSS
REFERENCE
NUMBER
1.

Response
to
Registrant
The
more
recent
use
and
sales
figures
do
not
change
the
overall
risk
conclusions.

Registrant
Comment
The
Agency
is
concerned
about
the
fact
that
an
acceptable
explanation
has
not
been
provided
to
explain
the
large
difference
in
half
life
between
the
lab
aerobic
metabolism
study
and
the
half
lives
in
the
field
dissipation
studies.
We
acknowledge
that
an
interpretation
for
the
differences
has
not
been
provided.
However,
there
are
substantial
data
available
to
indicate
that
the
field
data
numbers
are
valid
and
that
the
product
does
actually
degrade
rapidly
in
the
field.
In
the
field
dissipation
studies
cited
in
the
EFED
risk
assessment,
the
half
life
ranged
from
17­
24
days.
One
of
the
studies
was
done
with
the
DF
formulation
and
comprised
2
applications,
separated
by
one
month.
The
half
life
in
the
latter
study
was
17.4
days,
with
NO
indication
of
any
accumulation.
A
total
of
17
field
degradation
studies
were
undertaken
in
Germany,
USA
and
Canada
using
various
formulations
and
application
timings,
resulting
in
a
range
of
half
life
values
between
9
and
120
days.
Additional
studies
will
be
submitted
which
support
the
reliability
of
the
field
data
and
provide
experimental
evidence
that
there
is
no
accumulation.
We
believe
that
EPA's
concern
that
there
may
be
accumulation
is
not
justified
based
on
the
weight
of
the
evidence
from
higher
tier,
field
dissipation
studies.

The
fact
that
the
fastest
routes
of
dissipation
for
the
product
based
on
lab
studies
are
photolysis
(
soil
and
water)
does
not
negate
the
results
of
the
field
data.
EPA
comments
that
soil
photolysis
is
not
operative
because
of
soil
incorporation
and
aqueous
photolysis
is
not
operative
in
the
Page
5
of
10
presence
of
organics.
The
extent
to
which
these
mechanisms
operate
in
the
field
is
speculation,
whereas
there
is
substantial
field
data
that
confirms
the
product
does
not
accumulate
in
the
soil.

Response
to
Registrant
EFED
has
performed
a
cursory
analysis
of
these
studies
which
clearly
show
a
reduced
half­
life
in
the
field
compared
to
the
laboratory.
The
submitted
aerobic
soil
metabolism
study
(
MRID
46459104)
states
that
napropamide
degraded
by
hydrolysis
and
by
loss
of
the
N­
Alkyl
group
to
yield
naphthoxy
propionic
acid,
followed
by
non­
extractable
bound
residues
and
CO
2
.
However,
the
data
do
not
support
the
registrant's
conclusions.
Napropamide
is
hydrolytically
stable,
the
half­
lives
in
the
laboratory
studies
do
not
indicate
significant
degradation,
naphthoxy
propionic
acid
was
not
formed
in
significant
quantities,
and
"
extractable"
residues
(
acetonitrile)
accounted
for
the
bulk
of
the
residues
in
the
aerobic
soil
metabolism
studies
submitted
by
the
registrant.
Therefore,
the
most
likely
source
of
dissipation
in
the
environment
are
runoff,
erosion,
and
leaching.

Registrant
Comment
We
believe
that
the
use
of
the
correct
and
more
realistic
modeling
assumptions,
such
as
 
the
correct
vapor
pressure
(
1.7x10­
7
torr),
water
solubility
(
74
mg/
L),
aqueous
photolysis
half­
life
(
6.8
min)
 
field
dissipation
half
life
(
in
place
of
aerobic
soil
metabolism
half
life),
 
a
realistic
time
between
applications
(
such
as
90
days)
for
those
uses
with
more
than
one
application
per
season
rather
than
a
default
of
7
days,
and
 
a
lower
lbs.
ai
use
rate
to
reflect
the
band
applications
rather
than
broadcast,

will
reduce
the
calculated
EECs.

Response
to
Registrant
EFED
reran
the
PRZM­
EXAMS
modeling
using
the
inputs
suggested
by
the
registrant.
The
vapor
pressure
used
in
previous
modeling
was
incorrect
and
was
changed
to
reflect
the
correct
registrant
value,
but
made
no
difference
in
the
EECs.
The
suggested
water
solubility
(
74
mg/
L)
also
made
no
difference
because
PRZM­
EXAMS
only
uses
the
water
solubility
as
an
upper
bound.
The
EECs
were
in
the
ug/
L
(
parts­
per­
billion,
ppb)
range
and
were
not
affected
by
the
water
solubility
in
the
mg/
L
(
parts­
per­
million,
ppm)
range.
EFED
originally
used
an
aqueous
photolysis
half­
life
of
26
minutes
for
the
sum
of
parent
+
Isomer
I
+
Isomer
II
instead
of
6.8
minutes
for
parent
napropamide
only.
In
the
revised
assessment,
EFED
did
use
the
registrant
value
of
6.8
minutes
upon
further
consideration.
Given
the
relative
rapidity
of
photodegradation
for
both
half­
lives
and
the
fact
that
EXAMS
divides
the
aqueous
phototolysis
rate
by
124
to
account
for
suspended
sediment
and
shading,
the
different
half­
lives
made
no
difference.
It
is
scientifically
invalid
to
use
field
dissipation
half­
lives
in
PRZM­
EXAMS
modeling
because
field
Page
6
of
10
dissipation
takes
into
account
many
laboratory
dissipation
processes,
and
including
it
in
modeling
"
double
counts"
(
overestimates)
disappearance
of
a
compound.
PRZM­
EXAMS
takes
laboratory
dissipation
half­
lives
and
predicts
field
dissipation
half­
lives.
In
the
previous
"
error
only"
version
of
the
RED
chapter,
EFED
assumed
an
application
interval
of
7
days
in
the
absence
of
information.
The
use
of
an
extended
application
window
is
a
valid
comment
and
it
affected
the
modeling
results
by
reducing
EECs.
EFED
also
considered
the
banding
of
napropamide
as
a
valid
comment
and
specifically
modeled
those
applicable
scenarios.

Registrant
Comment
Although
EPA
does
acknowledge
that
napropamide
is
a
pre­
emergent
herbicide,
generally
applied
to
bare
ground,
it
is
not
clear
that
this
is
really
taken
into
account
in
the
risk
assessments.
The
vast
majority
of
the
agricultural
uses
(
with
the
exception
of
turf,
mint
and
cranberries),
are
via
band
applications
such
that
the
actual
amount
of
product
applied
to
the
field
(
vs.
broadcast)
is
lower.
Further,
the
product
must
be
either
soil
incorporated
(
where
applicable)
or
watered
in,
making
less
product
available
for
runoff
such
that
only
treatments
from
the
edges
of
agricultural
sites
(
i.
e.,
a
very
small
part
of
the
actual
amount
applied)
is
available
for
runoff.

Response
to
Registrant
EFED
did
model
the
runoff
from
field
treated
both
broadcast
and
banded
where
applicable.
Incorporation
depth
on
the
label
may
not
be
relevant
in
an
orchard
or
vineyard
because
mechanical
incorporation
is
not
possible
due
to
existing
root
structures.
The
labels
allow
up
to
3
weeks
before
incorporation
for
some
crops
and
locations
and
large
rainfall
events
may
occur
prior
to
that
time.
Therefore,
runoff
from
excess
rainfall
may
exceed
incorporation
in
this
case.

Registrant
Comment
The
Agency
believes
that
chronic
exposure
to
aquatic
organisms
is
possible
because
of
the
"
potential
persistence"
which
may
cause
chronic
exposure
to
aquatic
organisms.
We
believe
that
EPA
significantly
over­
estimates
the
amount
of
napropamide
in
the
soil
which
is
available
for
runoff.
In
addition,
the
aquatic
dissipation
mechanism
on
which
EPA
relies
 
aqueous
photolysis 
may
not
be
the
only
mechanism
available
to
reduce
the
amount
of
product
in
the
water
phase.
Sufficient
weight
must
be
given
to
the
following:
 
Based
on
the
use
pattern,
the
amount
of
napropamide
reaching
aquatic
environments
is
much
less
than
that
estimated
by
EPA.
 
The
field
dissipation
data
indicate
rapid
dissipation.
 
A
natural
sediment­
water
study
shows
that
the
product
partitions
from
the
water
phase
into
the
sediment
with
a
half­
life
of
24­
34
days
making
napropamide
less
available
to
the
aquatic
organisms.
Page
7
of
10
Response
to
Registrant
The
registrant
contends
that
the
persistence
in
the
field
is
less
than
EFED
predicts,
and
therefore
the
exposure
in
aquatic
systems
will
be
less
than
predicted.
As
stated
earlier,
the
dominant
routes
of
dissipation
in
the
field
appear
to
be
runoff,
erosion,
and
leaching.
The
registrant
also
contends
that
the
degradation
in
aquatic
systems
is
based
on
both
photolysis
and
metabolic
degradation.
Any
metabolic
degradation
would
only
be
expected
to
occur
in
the
water
phase
because
the
halflives
in
sediment
were
254
and
403
days.
However,
the
exact
study
to
which
the
registrant
is
referring
is
unknown.
The
OPPIN
database
of
submitted
studies
lists
MRID
45074201
as
the
submitted
study
for
degradation
in
water
(
Guideline
162­
4),
but
this
study
is
a
method
validation
study
for
determining
levels
of
napropamide
in
water.

Registrant
Comment
In
assessing
risk
to
terrestrial
organisms,
EPA
significantly
over­
estimated
exposure
primarily
due
to
the
use
of
non­
realistic
input
values
as
discussed
above.
Terrestrial
non
target
organism
exposure
from
the
use
of
this
herbicide
is
most
likely
to
occur
as
a
result
of
spray
drift
due
to
the
use
pattern.
The
product
is
generally
applied
in
a
band
(
with
the
exception
of
turf,
mint
and
cranberries)
under
and
near
the
agricultural
crop
being
grown.
As
a
result,
it
is
not
likely
that
there
would
be
significant
residues
in
other
areas
of
the
treated
fields.

Response
to
Registrant
EFED
assumes
that
drift
can
occur
both
in
the
field
and
outside
the
field.

Registrant
Comment
In
areas
adjacent
to
the
treated
fields,
there
is
a
potential
for
spray
drift
to
non­
target
organisms.
Given
the
mode
of
action
of
this
product,
it
is
not
likely
to
impact
established
plants
since
there
is
no
incorporation
of
the
product
in
these
areas.
Two
additional
studies
are
being
submitted
which
tested
seedling
emergence
 
with
and
without
soil
incorporation.
These
show
that
the
results
are
clearly
more
severe
with
incorporation 
a
practice
not
applicable
to
off
site
areas.
It
should
also
be
pointed
out
that
the
product
dissipates
rapidly
in
the
soil
and
by
photolysis
in
water
and
therefore
the
actual
exposure
to
non­
target
organisms
will
decline
quickly.

Response
to
Registrant
The
results
form
the
seedling
emergence
studies
are
included
in
this
assessment.
The
registrant
has
not
demonstrated
that
the
product
dissipates
rapidly
in
soil
other
than
runoff,
erosion,
and
leaching.
Page
8
of
10
Registrant
Comment
The
RQ's
calculated
will
improve
with
the
use
of
more
appropriate
inputs
to
the
EEC
calculations.
Nevertheless,
even
if
the
RQ's
as
calculated
using
the
conservative
lab
input
to
the
modeling
exceed
the
Levels
of
Concern,
there
is
no
evidence­­
after
25
years
of
Devrinol
use­­
suggesting
that
actual
adverse
effects
occur
from
the
existing
uses.

Response
to
Registrant
EFED
believes
that
the
lack
of
reporting
of
adverse
ecological
effects
does
not
mean
they
are
not
occurring.
Ecological
incidents
can
provide
useful
information
on
the
circumstances
where
impacts
occur
in
the
field
and
are
therefore
a
valuable
tool
for
risk
characterization.
However,
reliance
on
the
frequency
of
incidents
may
significantly
underestimate
the
extent
of
the
actual
impacts.
Adverse
ecological
effects
cannot
be
assumed
to
be
reliably
detected
and
reported.
Before
an
incident
can
be
reported,
it
must
be
observed
and
attributed
to
the
pesticide.
Also,
if
kills
are
not
reported
and
investigated
promptly,
there
will
be
little
chance
of
documenting
the
cause.
Reports
of
investigated
incidents
often
do
not
get
submitted
to
EPA,
since
reporting
by
states
is
voluntary
and
some
investigators
may
believe
that
they
do
not
have
the
resources
to
submit
incident
reports
to
EPA.

Registrant
Comment
The
agency
identified
key
information
gaps
that
prevented
the
full
assessment
of
the
potential
adverse
effects
of
napropamide
to
aquatic
plants
and
algae.
Registrant
comment:
The
registrant
submitted
two
studies
of
acute
toxicity
of
napropamide
to
Lemna
minor
(
MRID
464591­
11)
and
Anabaena
sp.
(
MRID
464591­
12).

EFED
response
Both
of
these
studies
have
been
classified
as
supplemental,
and
they
have
been
incorporated
into
the
risk
assessment.
These
studies
have
been
used
to
assess
risks
to
aquatic
plants
and
algae
associated
with
napropamide
use;
however,
EFED
acknowledges
the
existence
of
uncertainties
related
to
the
use
of
these
supplemental
studies
in
the
revised
risk
assessment.
Specifically,
the
Anabaena
study
was
conducted
for
3
days
instead
of
the
guideline
requirement
of
5
days.
As
a
result
there
is
uncertainty
associated
with
the
EC
50
that
was
identified
in
this
study.
The
Lemna
study
was
conducted
with
a
non­
guideline
species
instead
of
the
guideline
required
species,
Lemna
gibba.

Registrant
comment
The
registrant
submitted
two
seedling
emergence
studies
(
MRID
464591­
13
and
464591­
14)
in
support
of
their
claim
that
napropamide
is
less
toxic
to
plants
outside
the
area
of
application
because
it
is
not
incorporated
in
those
areas.
Page
9
of
10
EFED
response
MRID
464591­
13
is
classified
as
supplemental,
and
does
not
provide
additional
plant
toxicity
information
because
this
guideline
has
already
been
satisfied
with
an
acceptable
study.
MRID
464591­
14
is
classified
as
invalid
and
will
not
be
included
in
the
revised
risk
assessment.
Because
MRID
464591­
14
is
an
invalid
study,
EFED
cannot
use
these
data
to
evaluate
the
registrant's
comment
that
napropamide
is
less
toxic
to
non­
target
plants
when
not
incorporated.
Based
on
EFED's
revised
risk
assessment,
RQs
are
generally
higher
for
plants
under
scenarios
in
which
napropamide
is
not
incorporated.

The
agency
also
identified
key
information
gaps
that
prevented
the
full
assessment
of
the
potential
adverse
chronic
effects
of
napropamide
to
aquatic
animals.
Registrant
comment:
The
registrant
submitted
a
freshwater
fish
sub­
chronic
(
28­
day)
study
(
MRID
464591­
09)
and
an
aquatic
invertebrate
life
cycle
test
with
Daphnia
magna
(
MRID
464787­
04).

EFED
response
The
data
from
these
studies
have
been
incorporated
into
the
revised
risk
assessment.
The
subchronic
study
on
freshwater
fish
has
been
classified
as
supplemental,
as
it
does
not
meet
Agency
guidelines.
The
study
also
did
not
identify
the
ages
of
the
fish
when
the
study
began,
so
there
is
uncertainty
associated
with
the
use
of
this
study
in
establishing
a
NOAEC
upon
which
to
base
the
estimate
of
chronic
risk
to
freshwater
fish.
Chronic
studies
were
not
submitted
for
marine/
estuarine
fish
or
invertebrates,
so
these
data
requirements
have
not
been
fulfilled.

Registrant
comment
In
order
to
estimate
the
risk
of
napropamide
to
non­
target
insects,
the
registrant
submitted
two
studies
on
honey
bee
acute
contact
toxicity
(
MRID
464591­
15
and
464591­
16),
one
of
which
also
tests
acute
oral
toxicity
(
MRID
464591­
15).

EFED
response
The
two
tests
for
contact
toxicity
have
been
determined
to
be
invalid,
and
the
data
obtained
from
these
studies
will
not
be
used
in
the
revised
risk
assessment.
The
oral
toxicity
study
has
been
classified
as
supplemental,
and
has
been
incorporated
into
the
revised
risk
assessment.

Registrant
comment
The
registrant
submitted
proposed
changes
to
labels
specifying
revised
(
in
most
cases
reduced)
application
rates,
numbers
of
applications,
and
an
application
interval
of
90
days.
Page
10
of
10
EFED
response
EFED
must
use
language
contained
in
active
labels
to
establish
the
use
patterns
for
modeling
napropamide
exposure
in
the
ecological
risk
assessment.
The
proposed
label
changes
were
not
incorporated
into
the
revised
risk
assessment
because
they
have
not
been
officially
accepted.
However,
EFED
recognizes
that
some
proposed
label
changes
have
the
potential
to
reduce
risks
to
some
organisms
if
they
are
incorporated
into
the
labels.