UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON,
D.
C.
20460
OFFICE
OF
PREVENTION,
PESTICIDES
AND
TOXIC
SUBSTANCES
Date:
21­
JUN­
2006
MEMORANDUM
SUBJECT:
AMENDMENT
TO:
Bifenthrin:
Human
Health
Risk
Assessment
for
Proposed
Uses
on
Cilantro,
Leafy
Brassica
Greens,
Tuberous
and
Corm
Vegetables,
Dried
Shelled
Peas
and
Beans
and
Tobacco.
Date:
06­
April­
2006.
PC
Code:
128825.
DP
Barcodes:
DP313817,
DP313818,
DP310089,
DP313738,
DP310088,
DP310874.

Regulatory
Action:
Section
3
Registration
Action
Risk
Assessment
Type:
Single
Chemical
Aggregate
FROM:
Mary
Clock­
Rust,
Biologist
Registration
Action
Branch
1
(
RAB1)
Health
Effects
Division
(
HED)
(
7509C)

THROUGH:
Felecia
Fort,
Acting
Branch
Chief
And
PV
Shah,
Ph.
D.,
Branch
Senior
Scientist
RAB1
HED
(
7509C)

TO:
Barbara
Madden,
Minor
Use
Team
Registration
Division
(
RD,
7505C)
2
The
most
recent
human
health
risk
assessment
for
bifenthrin
(
memo,
M.
Clock­
Rust.
DP313817.
4/
6/
06.)
has
been
updated
with
the
addition
of
new
information
on
the
percent
of
crops
projected
to
be
treated
with
bifenthrin.
In
the
previous
assessment,
projections
of
bifenthrin
percent
crop
treated
for
uses
on
collards,
kale,
mustard
greens,
dried
beans/
peas,
okra,
and
sweet
potatoes
were
used.
BEAD
recently
provided
updated
information
for
four
crops:
collards,
kale,
mustard
greens
and
sweet
potatoes.
A
new
dietary
assessment
was
performed
using
the
new
information
from
BEAD,
assuming
100%
projected
percent
of
crop
treated.
No
other
changes
have
been
made
to
the
human
health
risk
assessment.
The
updated
risk
estimates
for
dietary
and
aggregate
risk
are
summarized
in
the
tables
below.
These
updated
tables
replace
the
corresponding
tables
in
the
April
6,
2004
risk
assessment.

Updated
Table
4.2.2:
Summary
of
Dietary
Exposure
and
Risk
for
Bifenthrin
Assuming
100
PCT
for
Collards,
Kale,
Mustard
Greens
and
Sweet
Potatoes
Acute
Dietary
(
99.9th
Percentile)
Chronic
Dietary
Population
Subgroup
Dietary
Exposure
(
mg/
kg/
day)
%
aPAD
Dietary
Exposure
(
mg/
kg/
day)
%
cPAD
General
U.
S.
Population
0.007985
24
0.000384
10
All
Infants
(<
1
year
old)
0.012467
38
0.000468
12
Children
1­
2
years
old
0.014044
43
0.001036
26
Children
3­
5
years
old
0.014204
43
0.000767
19
Children
6­
12
years
old
0.005499
17
0.000441
11
Youth
13­
19
years
old
0.007038
21
0.000295
7
Adults
20­
49
years
old
0.006971
21
0.000347
9
Adults
50+
years
old
0.006040
18
0.000304
8
Females
13­
49
years
old
0.005838
18
0.000258
6
3
Updated
Table
6.2.1.
Short­
and
Intermediate­
Term
Aggregate
Risk
for
Bifenthrin
Assuming
100
PCT
for
Collards,
Kale,
Mustard
Greens
and
Sweet
Potatoes
Population
Dietary
MOE1
Nondietary
Oral
MOE2
Dermal
MOE3
Inhalation
MOE4
Aggregate
MOE5
General
US
population
5,800
N/
A
600
23,000
530
All
infants
(<
1
yr
old)
4,700
590
1400
380
Children
1­
2
yrs.
Old
2,100
590
1400
350
Children
3­
5
yrs.
Old
2,900
590
1400
360
Children
6­
12
yrs.
Old
5,000
1400
1,100
Youth
13­
19
yrs.
Old
7,500
1400
N/
A
1,200
Adults
20­
49
yrs.
Old
6,400
600
540
Adults
50+
yrs.
Old
7,300
600
540
Females
13­
49
yrs.
Old
8,600
N/
A
510
23,000
470
1
Dietary
MOE
=
[(
short­
or
intermediate­
term
oral
NOAEL)
÷
(
chronic
dietary
exposure)];
NOAEL=
2.21
mg/
kg/
day;
chronic
dietary
(
food
+
water)
exposures
were
utilized
as
surrogates
for
short­
and
intermediate­
term
exposures
2
Non­
dietary
oral
MOE
=
[(
short­
or
intermediate­
term
oral
NOAEL)
÷
(
sum
of
all
high­
end
incidental
oral
residential
exposure)];
NOAEL=
2.21
mg/
kg/
day;
chronic
dietary
(
food
+
water)
exposures
(
see
Table
4.2.2)
were
utilized
as
surrogates
for
short­
and
intermediate­
term
exposures.
3
Dermal
MOE
=
[(
short­
or
intermediate­
term
dermal
NOAEL)
÷
(
high­
end
dermal
residential
exposure)];
NOAEL=
47
mg/
kg/
day;
structural
wood
treatment
(
paintbrush
application)
used
for
adult
estimates
4
Inhalation
MOE
=
[(
short­
or
intermediate­
term
inhalation
NOAEL)
÷
(
high­
end
dermal
residential
exposure)];
NOAEL=
2.21
mg/
kg/
day
5
Aggregate
MOE
(
dietary
and
residential)
=
1
÷
[
(
1
÷
Dietary
MOE)
+
(
1
÷
Non­
dietary
oral
MOE)
+
(
1
÷
Dermal
MOE)
+
(
1
÷
Inhalation
MOE)];
values
expressed
to
2
significant
figures;
Inhalation
MOE
based
on
adult
residential
handler
exposure
(
intermediate­
term
not
likely).
