UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON,
D.
C.
20460
DP
Barcodes:
D311925,
D311927,
D311929,
D311952,
D318281,
D318285,
D318286,
D318287,
D321441,
D321442,
D321443,
D321444,
D321445,
D321446,
D321937,
D321938,
D321942,
D321943,
D323440,
D325813.
PC
Code:
129099
MEMORANDUM
May
17,
2006
SUBJECT:
Drinking
Water
Assessment
for
Imidacloprid:
IR­
4
Registration
of
New
Uses
and
Modified
Application
Rates
TO:
Jennifer
R.
Tyler
RAB1/
HED
(
7509C)

FROM:
Ronald
D.
Parker,
Ph.
D.
Senior
Environmental
Engineer
ERB5/
EFED
(
7507C)

THRU:
Mah
Shamim,
Branch
Chief
ERB5/
EFED
(
7507C)

EXECUTIVE
SUMMARY.
This
memo
summarizes
the
Tier
I
estimated
drinking
water
concentrations
(
EDWCs)
for
new
uses
and
for
modified
rates
of
application
for
Imidacloprid
insecticide
on
several
crops.
These
crops
include
cotton,
tropical
fruit
(
including
sugar
apple,
citrus,
avocado),
oilseeds
crop
group
(
canola
and
rape),
coffee,
cranberry,
blackberry,
raspberry,
juneberry,
lingonberry,
pome­
granate,
tree
nuts
crop
group
14
(
including
pecan
and
pistachio),
banana
and
plantain,
herbs
subgroup
19A,
rye,
oat,
brassicas
and
leafy
vegetables.

These
surface
water
concentration
values
were
calculated
using
the
FQPA
Index
Reservoir
Screening
Tool
(
FIRST)
described
below.
New
ground
water
concentration
values
were
not
estimated
because
they
have
been
shown
previously
to
be
substantially
lower
in
magnitude
than
the
surface
water
concentrations.
See
Imidacloprid:
Tier
I
Drinking
Water
EECs
for
Use
in
the
Human
Health
Risk
Assessment",
February
25,
2003,
from
Michael
Barrett
(
EFED)
to
Jennifer
Tyler
(
HED)
attached
to
this
memo
as
Appendix
B.

EDWCs
for
these
new
Imidacloprid
uses
do
not
exceed
those
for
crops
evaluated
previously
and
therefore
overall
result
of
the
exposure
assessment
is
unchanged.
For
this
reason,
a
tier
II
assessment
with
the
PRZM
and
EXAMS
models
was
not
performed.
The
highest
acute
EDWC
for
the
new
crops
is
35.9
ppb
from
usage
on
tree
nuts.
The
previous
highest
acute
value
was
35.4
to
36.0
for
usage
on
citrus.
The
highest
chronic
EDWC
for
the
new
crops
is
15.3
ppb
from
usage
on
tree
nuts
and
coffee.
The
previous
highest
chronic
value
was
from
16.5
to
17.2
for
usage
on
citrus.
A
summary
of
the
model
input
parameter
values
used
in
FIRST
is
presented
in
Table
2.
FIRST
output
files
are
attached
in
Table
3.

PROBLEM
FORMULATION
This
is
a
Tier
I
drinking
water
assessment
that
uses
modeling
to
estimate
the
groundwater
and
surface
water
concentrations
in
drinking
water
source
(
pre­
treatment),
resulting
from
pesticide
use
on
sites
that
are
highly
vulnerable.
This
initial
tier
screens
out
chemicals
with
low
potential
risk
and
allows
OPP
to
focus
resources
on
more
refined
risk
assessments
for
chemicals
that
potentially
present
more
significant
risks.
This
drinking
water
assessment
will
report
potential
exposure
concentrations
for
the
human
health
dietary
risk
assessment
and
provide
a
clear
and
transparent
description
of
how
those
concentrations
were
determined.

ANALYSIS
Environmental
Fate
Summary
Imidacloprid
is
stable
to
hydrolysis,
and
typically
persists
for
many
months
in
soil.
However,
imidacloprid
appears
to
be
more
rapidly
transformed
under
anaerobic
conditions
and
appears
to
be
particularly
photolabile
in
pure,
clear
shallow
water.
Given
that
imidacloprid
is
mobile,
and
likely
to
be
highly
persistent
in
the
subsurface,
it
may
leach
to
ground
water
(
results
of
the
prospective
ground­
water
monitoring
studies
confirm
this).
Imidacloprid
may
also
pose
a
contamination
hazard
to
surface
waters
via
runoff,
and
may
be
especially
persistent
in
surface
water
with
high
turbidity.

The
environmental
fate
for
imidacloprid
is
as
follows
(
See
Appendix
D
for
further
details):

Water
solubility
(
200C)
=
580
ppm
Hydrolysis
(
pH
5
and
7)
=
stable
Hydrolysis
(
pH
9)
=
355
days
Photolysis
half­
life,
distilled
water
=
0.2
days
Photolysis
half­
life,
soil
=
39
(
estimates
from
the
single
study
range
from
39
to
171
days)
Aerobic
soil
metabolism
half­
life
=
359
(
188
to
660
days,
4
soils
including
1
in
U.
S.)
Anaerobic
Aquatic
=
27
days
Freundlich
adsorption
coefficient
between
0.96
to
4.76
Soil
leaching
(
Koc)
=
178
(
132
to
256)
ml/
g
Field
dissipation
half­
life
(
0
to
3­
inch
depth)
=
107
to
>>
365
days
(
5
sites)

EFED
concludes
that
the
available
data
on
imidacloprid
show
that
the
compound
is
mobile
and
persistent,
has
potential
to
leach
to
ground
water,
and
also
presents
concerns
for
transport
to
surface
water
by
runoff.
No
direct
environmental
fate
studies
have
been
conducted
for
the
degradates
{
several
of
which
retain
the
(
pyridinyl)
methyl­
imidazoli­
amine
backbone
of
the
imidacloprid
molecule},
including
the
following:
1)
imidacloprid
guanidine,
1­[(
6­
chloro­
3­
pyridinyl)
methyl]­
2­
imidazolidinimine
{
Alias
NTN
38014,
NTN
33823};
2)
imidacloprid
olefin,
1­[(
6­
chloro­
3­
pyridin1yl)
methyl]­
1,3­
dihydro­
2H­
imidazol­
2­
imine;
and
3)
imidacloprid
urea,
1­
[(
6­
chloro­
3­
pyridinyl)
methyl]­
2­
imidazolidinone.{
NTN
33519}.
Please
refer
to
the
Table
2
for
modeling
input
parameters.
See
Appendix
C
for
chemical
structures
of
these
degradates.

Use
Characterization
Table
1
is
a
summary
of
all
new
agricultural
use
patterns
for
Imidacloprid.
The
use
information
was
obtained
from
the
current
labels
for
products
containing
Imidacloprid.

Table
1.
Imidacloprid
Uses
and
FIRST
Drinking
Water
Exposure
Summary
Name
/
Formulation
Crops
Treated
Appl.
Methods
Max
Appl
Rates
(#
a.
i.
/
ac)
App/
year
Min.
Appl
Inter
1/
10
Peak
(
ppb)
1/
10
Ann.
(
ppb)
ENCORE
Imidacloprid
40.7%
Cotton
Aerial/
Ground
Spray
0.31
/
year
0.062/
appl
5
7
4.95
2.81
PROVADO
Solupak
75%
Cotton
Aerial/
Ground
foliar
spray
0.31
/
year
0.062/
appl
0.50
/
year
5
7
4.95
2.81
PROVADO
1.6
Flowable
Insecticide
17.4%
Cotton
Aerial/
Ground
Foliar
spray
0.31
/
year
0.062/
appl
0.50
/
year:
Pear,
citrus
Bushberry
Poplar,
Cottonwd
5
7
4.95
2.81
PROVADO
70
WG
Insecticide
17.4%
Cotton
Aerial/
Ground
Foliar
spray
0.31
/
year
0.062/
appl
0.5
/
year:
Artichoke,
Pear,
citrus
Bushberry
Poplar,
Cottonwd
5
7
4.95
2.81
PROVADO
Solupak
75%
Tropical
Fruit
(
Sugar
apple
Citrus
Avocado)
Aerial/
Ground
Foliar
spray
0.5
/
year
0.1
/
app
5
10
34.20
14.26
PROVADO
1.6
Flowable
Sugar
apple
Ground
0.5
/
year
0.1
/
appl
5
7
34.47
15.04
GAUCHO
Oilseeds­
slurry
mix
32
fl
oz.
1
N/
A
5.50
2.38
Name
/
Formulation
Crops
Treated
Appl.
Methods
Max
Appl
Rates
(#
a.
i.
/
ac)
App/
year
Min.
Appl
Inter
1/
10
Peak
(
ppb)
1/
10
Ann.
(
ppb)
480
Flowable
(
40.7%)
Crop
group
(
Canola
/
Rape)
(
0.25
gal)
per
CWT
of
seed:
.08#
a.
i./
ac
GAUCHO
480
Flowable
(
40.7%)
and
GAUCHO
600
Flowable
(
48.7%)
Oilseeds­
Crop
group:
(
Canola
/
Rape)
slurry
mix
25.6
fl
oz.
(
0.20
gal)
per
CWT
of
seed:

.08
lbs
a.
i./
ac
1
N/
A
5.50
2.38
PROVADO
1.6
Flowable
Coffee
(
Not
CA)
Aerial/
Ground
0.5
/
year
0.1
/
appl
5
7
34.74
15.31
ADMIRE
2
Flowable
Coffee
Chemig.
into
root
zone
drip
0.5
/
year
0.25­
0.5/
applic
1
N/
A
17.18
7.45
PROVADO
1.6
Flowable
Coffee
(
IR­
4)
Aerial/
Ground
0.5
/
year
0.1
/
appl
5
7
34.74
15.31
GAUCHO
550
SC
Cranberry
Blackberry
Raspberry
Chemig,
Drip,
Trickle
0.5
/
year
1
N/
A
17.81
7.45
GAUCHO
600
SC
Cranberry
Blackbrry
Raspberry
Chemig,
Drip,
Trickle
0.5
/
year
1
N/
A
17.81
7.45
ADMIRE
2
Flowable
Caneberry
blackberry
Raspberry,
Juneberry,
Lingonbry
Soil
Inject.
or
Drip
0.5
/
year
1
N/
A
17.81
7.45
ADMIRE
2
Flowable,
PROVADO
1.6
Flowable,
PROVADO
70
WG
GAUCHO
550
SC
GAUCHO
600
SC
Pomegranate
0.50
/
year
0.50
/
appl
ADMIRE
0.30
/
year
0.10
/
appl
PROVAD
O
1.6
1
3
N/
A
7
17.18
21.03
7.45
9.27
Name
/
Formulation
Crops
Treated
Appl.
Methods
Max
Appl
Rates
(#
a.
i.
/
ac)
App/
year
Min.
Appl
Inter
1/
10
Peak
(
ppb)
1/
10
Ann.
(
ppb)
ADMIRE
2
Flowable,
PROVADO
1.6
Flowable
Tree
Nuts
including
pecan,
and
pistachio
0.50
/
year
(
ADMIRE
0.36
/
year
0.09
/
app
PROV
1.6
1
4
N/
A
6
35.09
24.97
15.31
10.89
ADMIRE
2
Flowable,
Banana
and
Plantains
Chemig.
0.5
/
year
N/
A
17.18
7.45
PROVADO
1.6
Flowable
Banana
and
Plantains
Broadc/
directed
spray
0.1
/
year
5
14
33.85
14.77
PROVADO
70
WG
Banana
and
Plantains
Broadc/
dire
cted
spray
0.1
/
year
5
14
33.85
14.77
GAUCHO
550
17.18
17.18
7.45
GAUCHO
600
Banana
and
Plantains
Chemig.
similar
to
ADMIRE
0.5
/
year
0.5
/
year
1
1
N/
A
N/
A
7.45
ADMIRE
2
Flowable
Infurrow
Spray
directed
on
or
below
seed
or
chemig.
0.38
/
year
1
N/
A
13.76
6.04
PROVADO
1.6
Flowable
Herbs
Subgroup
19A
Aerial
and/
or
Ground
0.13
/
year
3
5
14.03
6.16
PROVADO
70
WG
Herbs
Subgroup
19A
Aerial
and/
or
Ground
appl
0.13
/
year
3
5
14.03
6.16
Rye
and
Oat
Seed
Treat.
0.125
/
treatment
1
N/
A
8.59
3.72
Brassica
&
Leafy
Veg.
Aerial/
Ground
0.08
/
appl
3
5
16.87
7.43
Table
2.
FIRST
Input
Parameters
for
Imidacloprid
New
Uses.
Parameter
Input
Source
Solubility
(
ppm)
580
Product
chemistry
submissions
Hydrolysis
t1/
2
@
pH
7
(
days)
Stable
MRID
42055337
Aerobic
soil
t1/
2
(
days)
520
MRIDs
452393­
01,
02,
42073501;
90%
upper
bound
confidence
limit
of
mean
Aerobic
aquatic
t1/
2
(
days)
1040
2x
the
aerobic
soil
input
value,
per
EFED
guidance
document
Photolysis
t1/
2
in
water
(
days)
39
Input
guidance
&
MRIDs
42256376;
42256377
Organic
carbon
partition
coefficient
­
Koc
(
mL/
g)
178
MRIDs
425208­
01
and
420553­
38
Application
rates
(
lb
a.
i./
Acre)
0.5
Label
maximum
rate
for
Tree
Nuts
(
Crop
Group
14)

Applications
/
year
1
Label
maximum
rate
for
Tree
Nuts
(
Crop
Group
14)

Application
spacing
N/
A
Label
maximum
rate
for
Tree
Nuts
(
Crop
Group
14)

Background
Information
on
FIRST:

FIRST
is
a
new
screening
model
designed
to
estimate
the
pesticide
concentrations
found
in
water
for
use
in
drinking
water
assessments.
It
provides
high­
end
values
on
the
concentrations
that
might
be
found
in
a
small
drinking
water
reservoir
due
to
the
use
of
pesticide.
Like
GENEEC,
the
model
previously
used
for
Tier
I
screening
level,
FIRST
is
a
single­
event
model
(
one
run­
off
event),
but
can
account
for
spray
drift
from
multiple
applications.
FIRST
uses
a
Drinking
Water
Reservoir
instead
of
a
pond
as
the
standard
scenario.
The
FIRST
scenario
includes
a
427
acres
field
immediately
adjacent
to
a
13
acres
reservoir,
9
feet
deep,
with
continuous
flow
(
two
turnovers
per
year).
The
pond
receives
a
spray
drift
event
from
each
application
plus
one
runoff
event.
The
runoff
event
moves
a
maximum
of
8%
of
the
applied
pesticide
into
the
pond.
This
amount
can
be
reduced
due
to
degradation
on
field
and
the
effect
of
binding
to
soil.
Spray
drift
is
equal
to
6.4%
of
the
applied
concentration
from
the
ground
spray
application
and
16%
for
aerial
applications.

FIRST
also
makes
adjustments
for
the
percent
crop
area.
While
FIRST
assumes
that
the
entire
watershed
would
not
be
treated,
the
use
of
a
PCA
is
still
a
screen
because
it
represents
the
highest
percentage
of
crop
cover
of
any
large
watershed
in
the
US,
and
it
assumes
that
the
entire
crop
is
being
treated.
Various
other
conservative
assumptions
of
FIRST
include
the
use
of
a
small
drinking
water
reservoir
surrounded
by
a
runoff­
prone
watershed,
the
use
of
the
maximum
use
rate,
no
buffer
zone,
and
a
single
large
rainfall.

Table
3.
Imidacloprid
FIRST
Output
Files
RUN
No.
1
FOR
Imidacloprid
ON
Herbs
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.380(
.380)
1
1
178.0
580.0
GROUND(
6.4)
87.0
2.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
13.756
6.039
RUN
No.
2
FOR
Imidacloprid
ON
Coffee
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.100(
.491)
5
7
178.0
580.0
AERIAL(
16.0)
87.0
.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
34.740
15.308
RUN
No.
3
FOR
Imidacloprid
ON
Oil
Seed
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.080(
.080)
1
1
178.0
580.0
GRANUL(
.0)
87.0
1.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
5.498
2.383
RUN
No.
4
FOR
Imidacloprid
ON
AugarApple
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.100(
.487)
5
10
178.0
580.0
GROUND(
6.4)
87.0
.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
34.203
14.925
RUN
No.
5
FOR
Imidacloprid
ON
Cotton
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.062(
.304)
5
7
178.0
580.0
AERIAL(
16.0)
20.0
.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
4.951
2.182
RUN
No.
6
FOR
Imidacloprid
ON
Caneberry
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.500(
.500)
1
1
178.0
580.0
GRANUL(
.0)
87.0
2.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
17.181
7.447
RUN
No.
7
FOR
Imidacloprid
ON
Herb2
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.130(
.387)
3
5
178.0
580.0
GROUND(
6.4)
87.0
2.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
14.027
6.158
RUN
No.
8
FOR
Imidacloprid
ON
SugarApple
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.100(
.491)
5
7
178.0
580.0
GROUND(
6.4)
87.0
.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
34.472
15.042
RUN
No.
9
FOR
Imidacloprid
ON
TreeNuts
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.500(
.500)
1
1
178.0
580.0
ABLAST(
6.3)
87.0
.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
35.093
15.311
RUN
No.
10
FOR
Imidacloprid
ON
Pomegranate
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.500(
.500)
1
1
178.0
580.0
GRANUL(
.0)
87.0
2.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
17.181
7.447
RUN
No.
11
FOR
Imidacloprid
ON
Pomegranate
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.100(
.297)
3
7
178.0
580.0
AERIAL(
16.0)
87.0
.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
21.032
9.267
RUN
No.
12
FOR
Imidacloprid
ON
LeafyVeg
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.800(
2.384)
3
5
178.0
580.0
AERIAL(
16.0)
87.0
.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
168.692
74.328
RUN
No.
13
FOR
Imidacloprid
ON
Banana
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.500(
.500)
1
1
178.0
580.0
GRANUL(
.0)
87.0
2.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)

­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
17.181
7.447
RUN
No.
14
FOR
Imidacloprid
ON
Banana
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.100(
.482)
5
14
178.0
580.0
GROUND(
6.4)
87.0
.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
33.851
14.771
RUN
No.
15
FOR
Imidacloprid
ON
Rye
Seed
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.125(
.125)
1
1
178.0
580.0
GRANUL(
.0)
87.0
1.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
8.591
3.724
RUN
No.
16
FOR
Imidacloprid
ON
TreeNuts
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.090(
.356)
4
6
178.0
580.0
ABLAST(
6.3)
87.0
.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
24.970
10.894
RUN
No.
17
FOR
Imidacloprid
ON
Coffee
*
INPUT
VALUES
*
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.500(
.500)
1
1
178.0
580.0
GRANUL(
.0)
87.0
2.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
520.00
2
N/
A
39.00­
4836.00
******
855.93
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.1.0
DEC
12,
2005
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
17.181
7.447
Appendix
B.
February
2003
Imidacloprid
Drinking
Water
Assessment
UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON,
D.
C.
20460
OFFICE
OF
PREVENTION,
PESTICIDES,
AND
TOXIC
SUBSTANCES
PC
Code:
129099
DP
BARCODES:
D271770,
D271825,
D278761,
D285742,
D286723,
D285499
MEMORANDUM
February
25,
2003
SUBJECT:
Imidacloprid:
Tier
I
Drinking
Water
EECs
for
Use
in
the
Human
Health
Risk
Assessment.

TO:
Jennifer
R.
Tyler
RAB1/
HED
(
7509C)

FROM:
Michael
R.
Barrett,
Ph.
D.
Chemist
ERB5/
EFED
(
7507C)

THRU:
Mah
Shamim,
Branch
Chief
ERB5/
EFED
(
7507C)

This
memo
summarizes
the
Tier
I
estimated
environmental
concentrations
(
EECs)
for
imidacloprid
total
residues
in
surface
water
and
in
ground
water
for
use
in
the
human
health
risk
assessments.
The
EECs
are
summarized
in
Table
1
(
Tier
1
EECs
for
parent
imidacloprid
alone
are
also
provided
for
comparison).
EFED
used
the
simulation
model
FIRST
to
calculate
the
surface
water
EECs
and
used
the
regression
model
SCI­
GROW
to
calculate
the
ground
water
EEC.
Insufficient
ground
and
surface
water
monitoring
data
are
available
to
fully
assess
exposure
from
monitoring
data.
Modeling
output
and
chemical
structures
of
imidacloprid
and
its
degradates
are
provided
in
Attachments
1
and
2,
respectively.

For
the
surface
water
and
ground
water
assessments
the
citrus
use
was
modeled,
which
has
the
highest
overall
seasonal
application
rate
(
modeled
as
two
applications
of
0.25
lb
ai/
A
at
a
14­
day
interval,
this
gives
the
highest
EECs
for
any
use
with
the
tier
I
models).
A
summary
of
the
model
input
parameter
values
used
in
FIRST
is
presented
in
Table
2.
A
summary
of
the
model
input
parameter
values
used
in
SCI­
GROW
is
presented
in
Table
3.

Updated
modeling
was
performed
using
the
FIRST
model
(
previous
modeling
was
performed
with
GENEEC,
which
has
been
replaced
with
FIRST
for
drinking
water
exposure
15
assessments
by
EFED).
In
the
absence
of
definitive
data
on
the
persistence
and
mobility
of
the
important
degradates
(
imidacloprid
urea,
imidacloprid
guanidine,
and
imidacloprid
olefin)
the
total
residues
were
modeled
using
tentatively
identified
total
residue
data
from
aerobic
soil
metabolism
studies
and
then
assuming
that
the
partitioning
of
all
residues
was
at
the
same
degree
as
imidacloprid
parent.
Each
of
these
assumptions
is
conservative
in
terms
of
tending
to
result
in
overestimate
of
exposure
except
for
with
respect
to
the
partioning
of
imidacloprid
urea,
which,
from
published
studies,
appears
to
be
more
mobile
than
the
parent
compound.
A
tendency
to
underestimate
imidacloprid
urea
with
this
procedure
should
not
significantly
affect
the
total
residue
Estimated
Environmental
Concentration
(
EEC)
calculations
in
this
review
because
the
extent
of
formation
of
imidacloprid
urea
in
soil
metabolism
studies
was
small
and
the
levels
of
the
urea
degradate
found
to
leach
in
field
studies
were
also
small.

Background
on
Imidacloprid
Total
Residue
Modeling
Inputs.
For
inputs
related
to
persistence
of
imidacloprid
total
residues,
the
sum
of
all
compounds
of
interest
was
subject
to
first­
order
regression
modeling
in
the
same
fashion
as
is
typically
done
for
parent
compounds
alone
in
EFED.
In
some
cases
the
registrant
did
not
unambiguously
identify
the
residues
chromatographed
from
soil
extracts,
in
these
cases,
the
peaks
containing
the
degradates
were
summed
with
the
realization
that
some
of
the
peaks
could,
in
addition
to
the
compounds
of
interest,
contain
some
amount
of
degradates
other
than
imidacloprid
urea,
imidacloprid
olefin,
or
imidacloprid
guanidine.

Information
on
imidacloprid
degradate
soil
mobility
is
found
in
both
guideline
studies
submitted
and
the
published
literature.
One
study
on
soil
adsorption
/
desorption
for
the
imidacloprid
guanidine
degradate
has
been
received
from
the
registrant
(
MRID
42520802);
Koc
values
ranged
from
327
to
942
g/
ml
in
five
soils
indicating
significantly
less
mobility
than
for
imidacloprid
parent.
In
published
studies
(
not
officially
submitted
to
EPA)
investigators
found
that
the
relative
mobility
of
imidacloprid
and
certain
degradates
was
imid.
urea
>
imidacloprid
>
imid.
olefin
>=
imid.
guanidine1
2
Separate
studies
with
the
degradates
on
persistence
and
mobility
(
especially
from
aerobic
soil
metabolism
and
batch
equilibrium
adsorption
/
desorption
studies)
submitted
to
OPP
under
Subdivision
N
(
Environmental
Fate
study)
guidelines
would
be
needed
to
more
accurately
model
the
total
residues,
especially
should
higher
tier
assessments
be
needed
in
1
Oliviera,
R.
S.,
W.
C.
Koskinen,
N.
R.
Werdin,
and
P.
Y.
Yen.
2000.
Sorption
of
imidacloprid
and
its
metabolites
on
tropical
soils.
J.
Environ.
Sci.
Health.
B35:
39­
49.

2
Cox,
L.,
W.
C.
Koskinen,
and
P.
Y.
Yen.
1997.
Sorption­
desorption
of
imidacloprid
and
its
metabolites
in
soils.
J.
Agric.
Food
Chem.
45:
1468­
1472.
16
the
future.
The
current
assessment
is
sufficiently
conservative
for
a
Tier
1
assessment
since
the
assumptions
for
the
parent
alone
already
estimate
near­
maximum
surface
water
exposure
(
as
demonstrated
by
the
small
differences
in
the
exposure
levels
between
the
parent
only
and
total
residue
EECs
in
Table
1).
The
very
high
persistence
of
imidacloprid
in
the
environment
is
the
primary
reason
that
only
a
small
increase
in
EECs
results
from
adding
degradates
in
this
Tier
1
assessment.

Table
1.
Estimated
Tier
1
concentrations
of
imidacloprid
in
drinking
water.

Surface
Water
(
ug/
L)
Groundwater
(
ug/
L)
Chemical
Acute
Chronic
Acute
and
Chronic
Imidacloprid
parent
35.28
to
35.89
2.18
to
16.52
1.43
Imidacloprid
total
residues
35.42
to
36.04
2.20
to
17.24
2.09
Table
2.
FIRST
input
parameters
(
pesticide
specific)
for
imidacloprid
total
residues:
citrus
modeling
scenario.

Parameter
Input
Source
Solubility
(
ppm)
580
Product
chemistry
submissions.

Hydrolysis
Half­
Life
(
pH
7)
(
days)
0
MRID
42055337
Aerobic
soil
t1/
2
(
days)
1016
MRIDs
452393­
01,
02,
42073501;
90%
upper
bound
confidence
limit
of
mean
Aerobic
aquatic
t1/
2
(
days)
2031
2x
the
aerobic
soil
input
value,
per
EFED
guidance
document
Photolysis
t1/
2
in
water
(
days)
0.2
to
391
Input
guidance
&
MRIDs
42256376;
42256377
Organic
carbon
partition
coefficient
­
Koc
(
mL/
g)
162
MRIDs
425208­
01
and
420553­
38
Application
rate
(
lb
a.
i./
Acre)
0.25
Label
­
max.
rate
for
citrus
(
foliar
application)

#
applications/
year
2
Label
maximum
for
citrus
Table
3.
SCI­
GROW
input
parameters
for
Imidacloprid.

Parameter
Input
Source
Aerobic
soil
metabolism
t1/
2
(
days)
483
MRIDs
452393­
01,
02,
&
03;
42073501;
mean
value
17
Koc
(
mL/
g)
172
MRIDs
425208­
01
and
420553­
38
Application
rate
(
lb
a.
i./
Acre)
0.5
Label
­
max.
rate
for
citrus
Review
of
Degradate
Monitoring
Data:
Degradate
exposure
was
assessed
both
through
monitoring
data
(
for
ground
water
sources
only)
and
modeling
(
both
ground
and
surface
water).
In
ground
water
sampled
from
two
small­
scale
Prospective
Ground­
Water
(
PGW)
Monitoring
study
sites,
the
degradates
imidacloprid
urea,
imidacloprid
guanidine,
and
imidacloprid
guanidine
olefin
were
all
a
very
minor
component
of
the
detected
residues.
However,
it
is
important
to
understand
that
total
residues
detected
were
almost
always
less
than
0.5
ppb
(
ug/
L)
and
usually
less
than
0.1
ppb
whereas
the
minimum
detection
limit
for
imidacloprid
and
each
of
its
degradates
was
0.03
ppb.
The
implication
of
this
is
that
theoretically,
degradation
products,
if
they
were
present
at
slightly
less
than
0.03
ppb
would
be
the
dominant
residues
present
in
many
samples.

At
the
Michigan
study
site,
imidacloprid
urea
was
the
most
commonly
detected
degradate
in
soil
pore
water,
but
generally
much
less
frequently
than
parent
imidacloprid
(
Table
2).
In
ground
water
imidacloprid
parent
was
consistently
detected
in
one
of
six
monitoring
well
clusters
in
the
treated
field
beginning
about
500
days
after
application
and
continuing
through
the
close
of
the
study
some
5
years
after
application.
No
degradation
products
were
detected
in
ground
water
during
this
period
(
there
were
a
very
few
detections
before
application
that
may
have
been
due
to
previous
uses
nearby
or
sample
contamination).
The
maximum
concentration
of
imidacloprid
parent
detected
in
ground
water
in
any
one
sample
at
the
Michigan
study
site
was
0.24
ppb.

Table
4.
Percentage
of
quantified
residues
present
as
degradation
products
at
representative
days
after
imidacloprid
treatment
in
soil
pore
water
at
a
9­
foot
depth:
Prospective
ground­
water
monitoring
study
in
Montcalm
County,
Michigan
(
1996
to
2001).

Days
after
Treatment
Lys.
ID
446
747
1126
1605
L1
nd
0.0%
21.4%
0.0%
L2
nd
0.0%
0.0%
0.0%
L3
0.0%
0.0%
0.0%
0.0%
L4
nd
nd
nd
nd
L5
nd
nd
0.0%
0.0%
L6
nd
0.0%
nd
nd
18
A
second
PGW
study
was
conducted
in
Monterrey
County,
California.
This
study
is
inadequate
to
fully
address
the
leaching
potential
of
imidacloprid
because
very
little
ground­
water
recharge
occurring
during
the
course
of
the
study
as
evidenced
by
the
almost
complete
lack
of
detection
of
the
bromide
tracer
(
applied
concurrently
with
imidacloprid)
in
ground
water.
The
limited
number
of
detections
in
soil
pore
water
and
ground
water
indicated
that
imidacloprid
urea
may
contribute
to
the
total
residue
that
leached
at
the
California
site.
No
imidacloprid
guanidine
or
imidacloprid
olefin
was
found
in
any
groundwater
sample.
Imidacloprid
urea
was
detected
in
seven
groundwater
samples
at
a
maximum
concentration
of
0.05
ppb
(
just
over
the
method
detection
limit
of
0.04
ppb).
The
maximum
combined
imidacloprid,
imidacloprid­
guanidine,
imidacloprid
olefin,
and
imidacloprid­
urea
residue
found
in
the
suction
lysimeters
was
0.62
ppb
at
633
days
post
application.
The
maximum
combined
imidacloprid
residue
in
the
ground
water
at
the
California
site
was
0.14
ppb
found
149
days
post
application.

Important
input
parameter
used
in
running
the
FIRST
and
SCI­
GROW
models
are
provided
in
Tables
3
and
4.
Modeling
output
and
chemical
structures
of
imidacloprid
and
its
degradates
are
provided
in
Attachments
1
and
2,
respectively.

ATTACHMENT
1:
FIRST
Files
RUN
No.
1
FOR
Imidacloprid
Total
Residues
ON
Citrus
*
INPUT
VALUES
*
Long
photolysis
half­
life
(
39
days)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.250(
.498)
2
14
161.0
580.0
AERIAL(
16.0)
87.0
.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
1016.00
2
N/
A
39.00­
4836.00
******
1430.31
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.0
AUG
1,
2001
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
36.040
17.243
RUN
No.
2
FOR
Imidacloprid
Parent
ON
Citrus
*
INPUT
VALUES
*
Long
photolysis
half­
life
(
39
days)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.250(
.496)
2
14
161.0
580.0
AERIAL(
16.0)
87.0
.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
19
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
602.00
2
N/
A
39.00­
4836.00
******
963.36
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.0
AUG
1,
2001
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
35.894
16.518
RUN
No.
3
FOR
Imidacloprid
Total
Residues
ON
Citrus
INPUT
VALUES
*
Short
photolysis
half­
life
(
0.2
days)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.250(
.498)
2
14
161.0
580.0
AERIAL(
16.0)
87.0
.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
1016.00
2
N/
A
.20­
24.80
******
24.50
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.0
AUG
1,
2001
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
35.419
2.201
RUN
No.
4
FOR
Imidacloprid
parent
ON
Citrus
*
INPUT
VALUES
*
Short
photolysis
half­
life
(
0.2
days)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
RATE
(#/
AC)
No.
APPS
&
SOIL
SOLUBIL
APPL
TYPE
%
CROPPED
INCORP
ONE(
MULT)
INTERVAL
Koc
(
PPM
)
(%
DRIFT)
AREA
(
IN)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.250(
.496)
2
14
161.0
580.0
AERIAL(
16.0)
87.0
.0
FIELD
AND
RESERVOIR
HALFLIFE
VALUES
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
METABOLIC
DAYS
UNTIL
HYDROLYSIS
PHOTOLYSIS
METABOLIC
COMBINED
(
FIELD)
RAIN/
RUNOFF
(
RESERVOIR)
(
RES.­
EFF)
(
RESER.)
(
RESER.)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
602.00
2
N/
A
.20­
24.80
******
24.30
UNTREATED
WATER
CONC
(
MICROGRAMS/
LITER
(
PPB))
Ver
1.0
AUG
1,
2001
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
PEAK
DAY
(
ACUTE)
ANNUAL
AVERAGE
(
CHRONIC)
CONCENTRATION
CONCENTRATION
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
35.275
2.175
20
SCI­
GROW
Modeling
Results:

SCIGROW
VERSION
2.2:
NOVEMBER
1,
2001
RUN
No.
2
FOR
Imidacloprid
Parent
**
INPUT
VALUES
**
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
APP
RATE
APPS/
TOTAL/
SOIL
AEROBIC
SOIL
METAB
(
LBS/
AC)
YEAR
SEASON
KOC
HALFLIFE
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.250
2
.500
172.0
340.00
GROUND­
WATER
SCREENING
CONCENTRATION
(
IN
UG/
L
­
PPB)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
1.429716
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

RUN
No.
3
FOR
Imidacloprid
Total
Residues
**
INPUT
VALUES
**
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
APP
RATE
APPS/
TOTAL/
SOIL
AEROBIC
SOIL
METAB
(
LBS/
AC)
YEAR
SEASON
KOC
HALFLIFE
(
DAYS)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
.250
2
.500
172.0
483.00
GROUND­
WATER
SCREENING
CONCENTRATION
(
IN
UG/
L
­
PPB)
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­
2.090082
­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­­

APPENDIX
C:
Imidacloprid
and
Degradates
Mentioned
in
this
Memorandum
21
22
Appendix
D:
Environmental
Fate
and
Transport
a.
Degradation
Hydrolysis
of
Imidacloprid
(
161­
1) 
Imidacloprid
was
stable
to
hydrolysis
in
pH
5
and
7
buffer
solutions,
and
slowly
degraded
at
pH
9
with
an
extrapolated
half­
life
of
355
days
(
MRID
42055337;
EFGWB
review
nos.
92­
0210,
92­
0196).
No
degradation
products
accumulated
significantly
during
the
course
of
the
study.

Photolysis
in
water
(
161­
2)
­
The
only
environmental
fate
study
in
which
extensive
degradation
occurred
within
a
period
of
hours
or
a
few
days
was
the
aqueous
photolyis
study
(
MRID
42256376;
EFGWB
reviews
no.
92­
0847,
92­
1039,
and
92­
1042).
The
possibility
of
rapid
photolysis
has
some
obvious
implications
for
surface
water
exposure,
but
should
not
be
assumed
to
universally
occur
in
surface
waters
because
there
is
not
supporting
evidence
from
surface
water
monitoring
studies,
the
photolytic
rate
can
be
substantially
different
from
distilled
water
in
natural
waters,
and
the
amount
of
pesticide
actually
exposed
to
sunlight
can
be
quite
low
in
many
surface
waters.

Imidacloprid
degraded
with
an
"
environmental"
half­
life
of
4.2
hours
(
0.2
days)
in
pH
7
buffer
solutions
maintained
at
24
C.
The
50%
and
75%
disappearance
times
were
approximately
1
and
2
hours,
respectively.

Residue
analysis.
Thin­
layer
chromatography
(
TLC)
in
multiple
solvent
systems
and
radiometric
detection
(
exposure
of
TLC
plates
to
X­
ray
film)
was
used
to
confirm
the
identity
of
imidacloprid
and
two
degradation
products.
In
addition,
residues
were
also
determined
with
reverse
phase
high­
performance
liquid
chromatography
(
HPLC).
A
linear
analyzer
was
used
to
quantify
residues
eluted
on
TLC
plates.
Imidacloprid
guanidine
was
the
most
prominent
degradate,
accumulating
to
17%
of
the
applied
imidacloprid
at
the
last
sampling
interval
2
hours
after
treatment.
The
only
other
degradation
product
that
was
identified
was
imidacloprid
urea,
which
constituted
10%
of
the
applied
material
2
hours
posttreatment.
No
effort
was
made
to
carry
the
experiment
on
to
follow
the
degradation
of
imidacloprid
more
completely,
and
other
degradation
products
were
not
identified.
Two
other
separated,
but
unidentified
photodegradation
products
reach
maximum
levels
of
13%
and
8%
of
the
applied
imidacloprid
when
the
experiment
was
terminated
after
2
hours
of
irradiation. 

The
initial
concentration
of
imidacloprid
was
5.4
mg/
l
(
5400
ppb)
in
sterile,
buffered
solution.
The
study
was
conducted
with
a
Xenon
lamp
rather
than
natural
sunlight
(
the
study
summary
mentions
that
"
under
natural
sunlight
60%
of
the
compound
were
[
sic]
degraded
after
4
hours",
but
a
detailed
description
of
the
natural
sunlight
experiment
was
not
provided).
The
light
intensity
of
the
lamp
was
8.9
to
9.5
uW/
cm2
compared
to
4.1
to
5.3
uW/
cm2
for
"
sunlight
intensity
on
bright
days"
at
the
Yuki
Institute
in
Japan,
where
the
experiment
was
apparently
conducted.
Imidacloprid
was
shown
to
be
more
stable
in
sterile
solution
kept
in
the
dark,
but
the
last
sample
was
taken
only
after
two
hours.
23
This
study
failed
to
identify
most
of
the
residues
by
two
hours
after
application,
and
also
failed
to
demonstrate
the
long­
term
stability
of
imidacloprid
in
the
dark
control.
Although
the
stability
of
imidacloprid
at
pH
7
in
solution
has
been
demonstrated
in
a
separate
hydrolysis
study,
this
should
have
been
confirmed
in
the
exact
same
solution
that
was
used
for
the
photolysis
study.
A
further
limitation
was
that
the
long­
term
stability
of
imidacloprid
degradation
products
to
photolysis
was
not
evaluated.

Photolysis
on
soil
(
161­
3)
 
Imidacloprid
degraded
with
a
registrant­
calculated
second­
order
half­
life
of
39
days
(
calculated
environmental
half­
life
of
171
days).
Two
experiments
were
run,
one
for
5
and
the
other
for
15
days.
At
the
end
of
the
15
days,
imidacloprid
parent
accounted
for
81.6%
of
the
applied
radioactivity;
consequently
an
accurate
estimate
of
the
degradation
rate
under
the
conditions
of
this
test
is
not
possible.

Aerobic
soil
metabolism
(
162­
1)
 
Imidacloprid
degraded
in
a
Kansas
sandy
loam
soil
(
series
name
or
classification
unknown;
MRID
421073501)
with
a
half
life
well
over
1
year
(
the
duration
of
the
study),
extrapolation
of
the
data
with
assumption
of
continued
decay
at
a
first­
order
rate
results
in
a
calculated
half­
life
of
660
days
(
Table
E­
1).
In
contrast,
in
three
European
soils
(
MRID
452393),
the
first­
order
half­
lives
were
calculated
to
be
248,
341,
and
188
days.
The
mean
first­
order
half­
life
was
359
days
(
90%
upper
bound
confidence
value
of
520
days);
however
there
appeared
to
be
greater
persistence
during
the
latter
part
of
these
studies
than
predicted
by
a
simple
first­
order
model.
These
studies
were
conducted
at
20
C
(
except
22
C
for
the
Kansas
soil),
persistence
might
have
been
lower
at
25
C,
the
temperature
of
most
laboratory
soil
metabolism
studies.

Under
aerobic
conditions
no
specific
compound
has
been
identified
as
accumulating
to
10%
or
more
of
the
applied
in
soil
or
water.
The
lack
of
identification
of
major
degradates
was
a
factor
of
both
the
limited
transformation
of
parent
compound
over
the
duration
of
these
studies
and
the
failure
to
identify
the
nature
of
much
of
the
residues.

Anaerobic
soil
metabolism
(
162­
2)
­
No
anaerobic
soil
metabolism
study
has
been
conducted;
however,
an
anaerobic
aquatic
soil
metabolism
study
was
conducted
in
lieu
of
this
study.

Anaerobic
aquatic
soil
metabolism
(
162­
2)
­
Imidacloprid
degradation
was
evaluated
in
a
water
/
sediment
mixture
(
obtained
from
a
pond
in
Stilwell,
Kansas)
(
MRID
42256378).
Characteristics
of
the
sediment
were:
silt
loam
textural
class
(
14%
sand,
58%
silt,
28%
clay),
3.2%
organic
matter,
pH
6.9.
The
pond
water
was
not
characterized.
The
study
was
conducted
with
500
ml
pond
water
and
100
g
of
sediment
in
flasks
under
unspecified
conditions;
imidacloprid
was
added
to
the
overall
system
at
a
concentration
of
0.56
ppm
(
presumably
part
per
million
by
weight).
The
incubation
flasks
were
purged
with
nitrogen
and
the
maintenance
of
anaerobic
conditions
was
documented
with
periodic
measurement
of
redox
potential,
pH,
and
oxygen
concentration.
Imidacloprod
degraded
with
a
first
order
anaerobic
half­
life
of
27
days
over
the
358­
day
postapplication
incubation
period.
Under
the
anaerobic
conditions
of
this
study,
imidacloprid
underwent
a
nitro­
reduction
reaction
to
the
degradate
imidacloprid
guanidine,
a
compound
which
24
accumulated
to
66%
of
applied
249
days
after
application
of
parent
imidacloprid.
Imidacloprid
guanidine
appears
to
be
extremely
persistent
under
anaerobic
conditions;
residues
of
this
degradate
still
represented
64%
(
50%
in
the
sediment
and
14%
in
the
water)
of
the
applied
imidacloprid
at
the
last
sampling
date
of
358
days
posttreatment.
Virtually
no
mineralization
of
imidacloprid
occurred,
evolved
carbon
dioxide
represented
less
than
0.2%
of
the
applied
imidacloprid.

b.
Mobility
Mobility/
Adsorption/
Desorption
(
163­
1)
­
Based
on
two
sets
of
batch
equilibrium
studies
(
MRID
420553­
38
­
American
soils;
and
M
in
a
total
of
eight
soils
(
four
American
and
four
German),
parent
imidacloprid
is
moderately
mobile
with
Freundlich
adsorption
coefficients
ranging
between
0.96
and
4.76.
Soil
organic
carbon
partition
coefficients
(
Koc)
values
did
not
vary
greatly,
the
range
for
eight
soils
was
132
to
256
ml/
g
(
161
to
239
for
the
four
American
soils)
with
an
average
Koc
of
178.
Results
for
the
American
and
German
soil
studies
are
given
in
Tables
E­
2
and
E­
3,
respectively.
Several
articles
reflecting
further
research
on
imidacloprid
sorption
in
soil
have
since
been
published
in
the
open
literature,
which
provide
insight
into
topics
such
as
the
increased
sorption
observed
with
time
and
also
with
lower
initial
concentrations
of
imidacloprid
in
soil
water.
Sorption
coefficients
measured
in
published
studies
are
generally
in
the
same
range
as
the
registrant­
submitted
studies,
at
least
over
the
short­
term
(
Oi,
1999,
Cox
et
al.
1998).

In
addition
to
the
above­
mentioned
studies,
an
aged
soil
column
leaching
study
with
imidacloprid
parent
(
MRID
420553­
39)
and
an
adsorption
/
desorption
study
with
imidacloprid
guanidine
(
MRID
425208­
02)
have
been
completed.
In
the
imidacloprid
guanidine
study
the
same
four
American
soils
were
studied
as
with
the
parent
compound
(
compare
Table
E­
4
with
Table
E­
2).
The
degradate
was
more
strongly
adsorbed
than
parent
imidacloprid
in
all
four
of
the
test
soils.

Prospective
ground­
water
studies.

Prospective
ground­
water
studies
have
been
conducted
at
two
locations
and
in
both
cases
the
predominant
compound
detected
in
soil,
soil­
pore
water
throughout
the
vadose
zone,
and
in
ground­
water
(
when
detectable)
was
parent
imidacloprid.
Of
the
three
degradates
analyzed
for
(
imidacloprid
guanidine,
olefin,
and
urea
derivatives)
only
imidacloprid
urea
leached
at
concentrations
that
were
frequently
detectable
(
minimum
detection
limit
of
0.02
ug/
L).

There
is
a
possibility
that
exposure
to
these
degradates
could
be
significant.
Therefore,
it
is
important
that
either
specific
analytical
methods
for
the
degradates
or
some
sort
of
total
residue
method
for
residues
in
water
and
soil
samples
should
be
developed
and
made
publicly
available
(
specific
methods
would
be
required
for
any
degradate
identified
as
being
of
toxicological
concern).

c.
Accumulation
25
Accumulation
in
Laboratory
Fish
(
165­
4)
This
data
requirement
has
been
waived.
Octanol/
water
partitioning
(
Kow)
data
provided
by
the
registrant
implies
a
low
potential
to
bioaccumulate
(
Kow
for
imidacloprid
=
3.7
@
21
C).

d.
Field
Dissipation
Terrestrial
field
dissipation
(
164­
1).
Terrestrial
field
dissipation
studies
have
been
submitted
from
Georgia
(
loamy
sand,
bareground),
Minnesota
(
sandy
loam,
planted
to
corn),
California
(
sandy
loam,
planted
to
tomatoes),
Minnesota
(
loam,
turf
plot),
and
a
Georgia
loamy
sand
(
turf
plot)
(
Table
E­
5).
The
dissipation
half­
lives
(
based
on
analyses
of
0­
6
inch
soil
cores
only)
ranged
from
107
days
to
much
greater
than
1
year
(
no
significant
dissipation
over
the
one
year
of
the
study
at
three
of
the
sites).
In
each
of
these
studies
a
single
or
broadcast
application
at
0.5
lb
ai/
A
was
made.

e.
Special
Field
Studies
Small­
Scale
Prospective
Ground­
Water
Monitoring
Studies
(
164­
1).

The
registrant
is
currently
conducting
two
small­
scale
Prospective
Ground
Water
Monitoring
studies:
one
each
in
Montcalm
County,
Michigan
and
Monterey
County,
California.
In
both
studies,
the
registrant
is
monitoring
for
imidacloprid
parent,
imdacloprid
guanidine,
imdiacloprid
olefin,
and
imidacloprid
urea
in
the
vadose
zone
and
in
shallow
ground
water.

In
the
California
study
(
located
near
Salinas,
Monterey
County)
imidacloprid
was
applied
at
0.45
lb
ai/
A
within
the
planting
furrow
(
broccoli
crop)
in
July
1996.
At
this
site,
more
leaching
of
imidacloprid
residues
has
been
found
to
occur
in
the
"
control"
plot
than
in
the
treated
area.
The
registrant
believes
the
imidacloprid
found
in
control
plot
samples
is
from
four
foliar
applications
of
imidacloprid
in
1995
and
1996.
Although
it
appears
that
sufficient
irrigation
water
has
been
applied
at
this
site
to
facilitate
some
ground­
water
recharge,
interpretation
of
this
study
is
complicated
by
the
relative
insensitivity
of
the
analytical
method
for
the
conservative
tracer
(
bromide)
to
be
used
to
confirm
this.
In
fact,
there
have
been
only
a
handful
of
detections
of
bromide
in
the
first
3+
years
of
sampling
of
ground
water,
providing
no
definitive
evidence
that
sufficient
water
has
been
applied
at
the
site
for
any
pesticide
residues
to
reach
ground
water.
Our
conclusion
therefore
is,
that
even
though
there
have
only
been
three
detections
of
imidacloprid
in
ground
water
(
at
0.09,
0.10
and
0.14
ppb;
the
method
has
a
claimed
ability
to
quantitate
imidacloprid
at
0.01
ppb
in
water
samples
although
apparently
only
detections
above
0.05
ppb
have
been
reported),
there
still
could
be
substantial
potential
for
imidacloprid
to
leach
to
ground
water
following
application
to
irrigated
vegetable
or
fruit
crops
in
California
(
if
sufficient
water
is
added
and
time
allowed
for
the
aquifer
to
be
recharged
with
water
from
the
surface
postttreatment).
Additionally,
we
note
that
all
three
of
the
imidacloprid
degradates
were
detected
leaching
through
the
vadose
zone
and
there
were
also
a
few
detections
of
imidacloprid
urea
in
ground
water
at
the
California
study
site.
26
In
the
Michigan
study
(
located
near
Vestaburg,
Montcalm
County)
imidacloprid
was
applied
at
0.34
lb
ai/
A
by
an
unspecified
method
(
potato
crop)
May
31,
1996.
Imidacloprid
has
been
found
to
be
leaching
at
a
variable
rate
and
concentration
in
all
six
of
the
lysimeter
clusters
with
residues
so
far
having
occasionally
exceeded
1
ppb
at
12
feet,
the
lowest
depth
sampled
(
Figure
2).
Residues
in
ground
water
so
far
are
somewhat
lower,
reaching
up
to
0.24
ppb
(
Figure
3).
This
study
is
ongoing,
and
it
appears
there
may
be
a
potential
for
higher
residue
levels
to
be
detected.
Note
that
the
Tier
1
screening
model
concentration
of
1.4
ppb
is
higher
than
residues
observed
in
ground­
water
but
lower
than
the
concentration
observed
in
the
deepest
soil
pore­
water
(
12­
foot
depth)
at
the
Michigan
study
site.
Complete
breakthrough
into
ground
water
had
not
yet
clearly
been
observed;
consequently
it
is
possible
that
higher
concentrations
of
imidacloprid
in
ground
water
could
still
be
observed.
Consistent
with
this
is
that
residues
in
the
deepest
soil­
pore
water
and
in
groundwater
were
increasing
in
most
lysimeter
and
well
clusters
at
some
point
during
the
last
year
of
sampling
(
there
has
been
a
marked
seasonal
fluctuation
in
concentrations
in
imidacloprid
in
soil
pore­
water).

f.
Other
(
non­
registrant)
Ground­
Water
Monitoring
Recently,
EPA
has
received
several
reports
summarizing
monitoring
of
ground
water
that
is
vulnerable
to
contamination
in
New
York
state
(
primarily
Long
Island).
For
imidacloprid,
there
have
been
about
27
detections
of
imidacloprid
above
a
detection
limit
of
0.2
ppb
in
about
5000
ground
water
samples
taken
by
the
Suffolk
County
Department
of
Health
Services,
to
date,
with
much
of
the
monitoring
targeted
to
areas
with
known
histories
of
imidacloprid
use
and
previously
documented
ground­
water
contamination
issues.
Overall,
imidacloprid
detections
are
rare
in
drinking
water
wells.
Three
wells
had
detections
above
the
model­
predicted
maximum
of
1.4
ppb.
After
closer
investigation,
however,
EPA
has
concluded
that
those
three
wells
are
not
reliable
indicators
of
imidacloprid
values
that
can
be
expected
in
groundwater
from
agricultural
use
of
imidacloprid.
The
first
of
these
wells
is
a
private
well
in
Mattituck,
Long
Island
in
which
imidacloprid
was
found
at
a
level
of
6.69
ppb.
An
investigation
by
the
New
York
authorities,
however,
concluded
that
these
high
levels
were
due
to
misuse
of
the
pesticide
in
a
greenhouse
adjacent
to
the
well
where
imidacloprid
contaminated
water
was
drained
onto
the
ground
in
the
immediate
vicinity
of
the
well.
The
second
well
was
one
of
five
shallow
monitoring
wells
installed
directly
down
gradient
from
imidacloprid
use
sites
for
the
purpose
of
monitoring
pesticide
levels.
One
of
those
wells,
"
Jamesport
B­
2",
showed
levels
of
imidacloprid
as
high
as
2.06
ppb.
It
was
discovered,
however,
that
this
well
was
in
all
likelihood
contaminated
as
a
result
of
a
manmade
sump
nearby
that
was
constructed
to
alleviate
ponding
in
the
field
and
directly
connected
surface
water
to
ground
water.
Imidacloprid
was
detected
in
only
one
of
the
other
five
wells,
and
the
level
of
imidacloprid
detected
in
the
other
well
did
not
exceed
0.24
ppb.
Finally,
imidacloprid
has
been
detected
in
shallow
ground
water
wells
directly
downgradient
from
a
site
investigating
use
of
tree
injection
treatments
of
imidacloprid.
The
highest
level
of
imidacloprid
found
in
these
wells
was
3.9
ppb.
These
wells,
however,
are
not
representative
of
wells
used
to
supply
ground
water
for
drinking
water.
The
wells
were
screened
at
extremely
shallow
depths
(
screens
beginning
only
4
to
10
feet
from
surface)
due
to
the
fact
that
the
depth
to
ground
water
averaged
about
five
feet.
27
It
was
concluded
by
the
researchers
(
EFED
makes
no
comment
on
this
at
this
time
without
further
investigation
ourselves)
that
these
wells
are
"
no
more
representative
of
what
would
likely
occur
in
drinking
water
supplies
than
pesticide
concentrations
in
samples
taken
from
a
weir
draining
an
agricultural
field
are
representative
of
what
would
occur
in
a
community
water
supply
drawing
from
a
river
or
reservoir
downstream."
