April
17,
2002
MEMORANDUM:

SUBJECT:
Lindane
(009001):
Revised
Dietary
Risk
and
Exposure
Estimate
For
Lindane
Through
Subsistence
Diets
for
Indigenous
People
of
Alaska.
DP
Barcode
#
D282455.
Reregistration
Case
0315.
MRID
No.
none.

FROM:
Thurston
G.
Morton,
Chemist
Reregistration
Branch
4
Health
Effects
Division
(7509C)

THROUGH:
Susan
V.
Hummel,
Branch
Senior
Scientist
Reregistration
Branch
4
Health
Effects
Division
(7509C)

TO:
Mark
Howard/
Betty
Shackleford
Reregistration
Branch
3
Special
Review
&
Reregistration
Division
(7508C)

INTRODUCTION:

The
occurrence
of
organochlorine
contaminants
in
the
Arctic
has
been
documented
in
several
studies.
A
variety
of
organochlorine
contaminants
including
lindane
has
been
found
in
terrestrial,
freshwater,
and
marine
habitats.
This
contamination
is
primarily
the
result
of
long
range
continental
transport
through
the
movement
of
the
air
and
ocean
currents.
The
source
of
the
lindane
is
unknown
but
most
likely
reflects
past
uses
other
than
seed
treatment.
Lindane
is
the
gamma
isomer
of
hexachlorocyclohexane
(HCH)
and
is
also
known
as
gamma
isomer
of
benzene
hexachloride
(BHC).
Technical
HCH
contained
the
alpha,
beta,
delta,
and
gamma
isomers
but
was
banned
in
the
United
States
in
the
1970s.
The
composition
of
technical
HCH
varied
widely,
but
often
the
alpha
isomer
was
the
predominant
isomer.
Lindane
(gamma
isomer
of
HCH)
remains
registered
in
the
U.
S.
as
a
seed
treatment
only.
Studies
have
shown
higher
concentrations
of
lindane
and
total
HCH
in
some
wildlife
from
west
to
east.
This
is
thought
to
be
due
to
the
direction
of
air
currents.
2
The
Indigenous
Peoples
of
the
Arctic
region
of
the
U.
S.
(Alaska)
rely
heavily
on
subsistence
diets
as
their
food
source.
Thus,
it
is
appropriate
for
the
Agency
to
perform
a
supplementary
dietary
risk
and
exposure
assessment
to
assess
the
risk
to
the
Indigenous
People
from
worldwide
use
and
manufacture
of
lindane.
This
memorandum
serves
to
update
the
previous
dietary
assessment
performed
for
the
indigenous
people
of
Alaska
by
incorporating
new
information
pertaining
to
subsistence
meat
intake
by
children.
Because
the
annual
harvest
rates
were
divided
by
365
to
obtain
daily
harvest
rates,
and
the
daily
intake
rates
used
in
the
assessment
no
acute
dietary
exposure
analysis
was
conducted.

EXECUTIVE
SUMMARY:


Using
subsistence
food
harvest
amounts,
total
HCH
residues
in
traditional
foods,
and
adjusting
the
HCH
exposure
(since
lindane
represents
between
3
and
15
%
of
total
HCH
residues)
to
obtain
lindane
exposure
results
in
an
range
of
exposures
of
0.
0039
­
0.
04231
mg/
day.
Thus
dividing
this
exposure
by
70
kg
(weight
of
adult
male)
would
result
in
a
range
of
exposures
for
the
male
Indigenous
People
to
lindane
of
0.000055
­
0.
00060
mg/
kg
bw/
day
which
is
3
­
38
%
cPAD
and
below
HED's
level
of
concern
(cPAD
=
0.0016
mg/
kg
body
weight/
day).
Dividing
the
range
of
exposures
of
0.0039
­
0.
04231
mg/
day
by
60
kg
(weight
of
adult
female)
would
result
in
a
range
of
exposures
for
the
female
Indigenous
People
to
lindane
of
0.000064
­
0.
00071
mg/
kg
bw/
day
which
is
4
­
44
%
cPAD
and
below
HED's
level
of
concern.
The
adult
intake
amounts
from
each
community
were
adjusted
by
a
factor
of
0.53
to
correct
for
the
difference
in
subsistence
meat
intake
between
children
and
adults.
These
adjusted
child
intake
amounts
were
then
used
to
calculate
a
range
of
lindane
dietary
risk
estimates
for
children
1­
6
years
old
resulting
from
subsistence
food
consumption
of
13
%
to
138
%
cPAD.
The
dietary
risk
estimates
resulting
from
subsistence
food
consumption
for
children
7­
12
years
old
was
448
%
of
the
cPAD.
The
child
risks
also
incorporates
the
range
of
potential
lindane
residues
relative
to
total
HCH
(i.
e.,
3­
15%).


HED
believes
these
estimates
may
be
an
overestimate
of
dietary
risk
since
dietary
intake
equaled
harvest
(i.
e.,
adults
consume
up
to
2.
4
pounds
of
subsistence
meat
per
day
and
children
consume
up
to
1.3
pounds
of
subsistence
meat
per
day).
Harvest
amounts
were
used
from
the
three
communities
of
approximately
180
Alaskan
communities
with
the
highest
seal
harvest,
highest
whale
harvest,
and
the
highest
walrus
harvest.
This
does
not
take
into
account
portions
of
the
harvest
which
were
discarded
or
used
for
non­
dietary
purposes.
Also,
the
maximum
detected
HCH
residue
concentration
was
used
in
the
calculation
of
the
HCH
exposure
in
the
respective
subsistence
food
item.
For
example,
the
beluga
whale
blubber
HCH
concentration
was
assumed
for
the
entire
harvest
(and
consumption)
amount
and
not
taking
into
account
other
tissues
consumed
which
may
have
had
much
lower
residue
amounts.
3
DETAILED
CONSIDERATIONS:

Memoranda
providing
details
of
relevant
toxicological
information
include
the
HIARC
report
dated
6/
18/
01
and
the
FQPA
Safety
Factor
Committee
report
dated
8/
2/
00.

The
acute
and
chronic
FQPA
safety
factors
of
10X
were
reduced
to
3X
(see
FQPA
Safety
Factor
Document,
8/
2/
00).
A
reference
dose
(RfD)
which
includes
the
FQPA
safety
factor
(typically
10X,
3X
or
1X)
is
defined
as
the
Population
Adjusted
Dose
(PAD).
Doses
and
endpoints
for
dietary
risk
assessment
are
presented
in
Table
1.

The
chronic
population
adjusted
dose
(cPAD)
for
lindane
is
0.0016
mg/
kg/
day.
The
cPAD
is
the
chronic
RfD
of
0.0047
mg/
kg/
day
divided
by
the
FQPA
factor
of
3
yielding
a
cPAD
of
0.0016
mg/
kg/
day.
The
chronic
endpoint
and
dose
is
listed
in
Table
1
below.

The
Agency
used
the
subsistence
food
harvest
amounts
of
nearly
180
communities
from
the
Community
Profile
Database
Version
3.
11
dated
3/
27/
01
from
the
Alaska
Department
of
Fish
and
Game
Division
of
Subsistence
as
subsistence
food
intake
rates.
This
is
a
database
which
includes
the
harvest
of
subsistence
foods
in
Alaskan
communities
from
the
years
1990­
2001.
From
personal
communication
with
Mr.
Roland
Shanks
from
the
Alaska
Inter­
Tribal
Council
it
was
determined
that
usually
only
two
of
the
following
marine
mammals
(walrus,
seal,
and
whale)
are
harvested
in
significant
amounts.
Therefore,
HED
used
the
community
with
the
highest
representative
seal
harvest,
the
community
with
the
highest
walrus
harvest,
and
the
community
with
the
highest
whale
harvest.
Generally
polar
bear
and
another
marine
mammal
were
also
used
along
with
the
harvest
of
significant
amounts
of
fish,
land
mammal,
and
birds
from
the
corresponding
Alaskan
community.
HED
used
the
per
capita
harvest
amount
as
the
human
intake
amount
which
would
be
a
conservative
estimate
since
some
of
the
harvest
would
be
used
for
nonhuman
food
purposes
and
waste.
Variability
in
intake
amounts
have
been
shown
between
tribal
communities
within
Western
Canada.
It
is
therefore
likely
that
there
would
be
variability
in
intake
rates
between
tribal
communities
in
Alaska
depending
on
the
availability
of
fish
and
game
meat.
The
adult
intake
amounts
were
adjusted
by
a
factor
of
0.53
to
obtain
the
intake
amount
for
children.
This
factor
was
derived
from
a
publication
(Heller,
1966)
1
.

Population
Community
Pt.
Hope
Notak
Shungnak
Adult
Males
438
grams
429
grams
573
grams
Children
7­
12
years
old
230
grams
230
grams
303
grams
Child's
%
of
Adults
Subsistence
Meat
Consumption
52.5
53.6
52.9
4
The
Agency
coupled
this
dietary
intake
data
with
organochlorine
residue
data
which
were
obtained
from
Dr.
Laurie
Chan
of
McGill
University
in
Canada
via
personal
communication.
The
report
gave
analytical
results
of
the
samples
for
total
hexachlorocyclohexane
(HCH)
and
not
the
individual
isomers.
Using
this
value
would
overestimate
the
risk
estimate
by
including
other
isomers
of
HCH
in
addition
to
lindane
which
is
the
gamma
isomer.
The
other
isomers
of
HCH
may
be
environmental
concentrations
resulting
from
previous
use
of
technical
HCH.
Therefore,
a
factor
of
0.03
or
0.15
was
used
to
multiply
the
total
HCH
exposure
to
account
for
exposure
to
lindane
only.
The
factor
of
0.03
or
0.15
was
derived
from
a
study
conducted
by
McGill
University
(Receveur,
1998)
in
which
lindane
and
total
HCH
was
measured.
Lindane
accounted
for
<3
to
15
%
of
the
total
HCH
present
in
samples
of
animal
tissue.

The
data
included
analytical
results
for
total
HCH
in
numerous
traditional
foods.
The
report
listed
a
maximum
residue
value
of
20
ng/
g
of
total
HCH
for
walrus
blubber,
215
ng/
g
for
ringed
seal
blubber,
9
ng/
g
for
moose
flesh,
1
ng/
g
for
caribou
flesh,
2
ng/
g
for
muskox
flesh,
4
ng/
g
for
Dall
sheep
flesh,
26
ng/
g
for
salmon
flesh,
20
ng/
g
for
whitefish
flesh,
6
ng/
g
for
arctic
char
flesh,
3
ng/
g
for
arctic
grayling
flesh,
1
ng/
g
for
cisco
flesh,
3
ng/
g
for
lake
trout
flesh,
348
ng/
g
for
ooligan
flesh
(which
in
this
assessment
will
be
used
for
cod,
smelt,
and
herring),
10
ng/
g
for
polar
bear
flesh,
391
ng/
g
for
beluga
whale
blubber,
7
ng/
g
for
eider
flesh,
1
ng/
g
for
goose
flesh,
4
ng/
g
for
gull
eggs,
and
10
ng/
g
preserved
soapberries.
Multiplying
the
maximum
HCH
concentration
in
the
traditional
food
by
the
harvest
amount
(converted
to
grams/
person/
day)
results
in
the
exposure
to
HCH
from
the
traditional
food
item.
Multiplying
the
residue
concentration
by
the
appropriate
traditional
food
amount
for
each
community
would
result
in
an
estimated
exposure
to
lindane
from
the
consumption
of
traditional
food.
Within
each
community,
the
individual
exposures
are
then
summed
for
a
total
exposure
to
lindane
in
traditional
food.

Summing
the
exposures
from
the
subsistence
food
sources
in
Community
1
(highest
total
exposure
of
the
three
communities)
amounts
to
an
exposure
to
total
HCH
of
282,065
ng/
day.
When
converted
to
mg/
day
this
exposure
becomes
0.
282065
mg/
day.
The
total
HCH
exposure
of
0.282065
mg/
day
must
be
adjusted
by
the
factor
of
0.03
or
0.15
(since
lindane
represents
between
3
and
15
%
of
total
HCH
residues)
to
obtain
the
lindane
only
exposure
yielding
a
lindane
exposure
for
Community
1
of
0.
0039
­
0.
04231
mg/
day.
This
value
must
be
divided
by
the
weight
of
an
adult
male/
female
in
kilograms
for
comparison
to
the
chronic
Population
Adjusted
Dose
(cPAD).
The
units
of
the
cPAD
are
mg/
kg
body
weight/
day.
The
cPAD
for
lindane
is
0.0016
mg/
kg
body
weight/
day.
Dividing
0.04231
(assuming
lindane
is
15%
of
total
HCH)
mg/
day
by
70
kg
(male
weight)
would
result
in
an
exposure
of
0.
0006
mg/
kg/
day.
Comparing
this
exposure
to
the
lindane
cPAD
of
0.0016
mg/
kg
body
weight/
day
reveals
that
the
exposure
of
the
male
Indigenous
People
to
lindane
is
38
%
cPAD
and
thus,
would
be
below
HED's
level
of
concern.
The
range
of
lindane
dietary
risk
estimates
for
adult
males
resulting
from
subsistence
food
consumption
is
3
%
to
38
%.
Dividing
0.
04231
mg/
day
by
60
kg
(female
weight)
would
result
in
an
exposure
of
0.0007
mg/
kg/
day.
Comparing
this
exposure
to
the
lindane
cPAD
of
0.0016
mg/
kg
body
weight/
day
reveals
that
the
exposure
of
the
female
Indigenous
People
to
lindane
is
44
%
cPAD
and
thus,
would
be
below
HED's
level
of
concern.
The
range
of
lindane
5
dietary
risk
estimates
for
adult
males
resulting
from
subsistence
food
consumption
is
4
%
to
44
%.
The
adult
intake
amounts
from
each
of
the
three
communities
were
adjusted
by
a
factor
of
0.53
to
incorporate
the
difference
in
subsistence
meat
intake
between
children
and
adults
1
.These
adjusted
child
intake
amounts
were
then
multiplied
by
the
respective
HCH
residue
amount
to
derive
a
total
HCH
exposure
from
each
subsistence
meat
source.
The
total
HCH
residue
amount
was
then
multiplied
by
0.
03
and
0.15
to
obtain
the
lindane
residue
amount.
The
lindane
residue
amount
was
then
divided
by
10
kg
(weight
of
child
1­
6
years
old),
and
then
by
0.
0016
(cPAD)
to
obtain
the
%
cPAD
which
was
occupied
by
the
lindane
exposure
from
subsistence
foods
(Table
3).
The
range
of
lindane
dietary
risk
estimates
for
children
resulting
from
subsistence
food
consumption
is
13
%
to
138
%.
For
children
7­
12
years
old,
the
lindane
residue
amount
was
divided
by
29
kg
(weight
of
child
7­
12
years
old),
and
then
by
0.
0016
(cPAD)
to
obtain
the
%
cPAD
which
was
occupied
by
the
lindane
exposure
from
subsistence
foods
(Table
4).
The
range
of
lindane
dietary
risk
estimates
for
children
resulting
from
subsistence
food
consumption
is
4
%
to
48
%
of
the
cPAD.

Table
1.
Lindane:
Toxicological
Doses
and
Endpoints
for
Dietary
Risk
Assessment.

EXPOSURE
SCENARIO
DOSE
(mg/
kg/
day)
ENDPOINT
STUDY
TYPE/
MRID
Chronic
Dietary
NOAEL=
10
ppm
(0.
47
mg/
kg/
day)

UF
=
100
FQPA
=
3X
LOAEL
is
100
ppm
(4.
81
mg/
kg/
day)
periacinar
hepatocyte
hypertrophy,
increased
liver/
spleen
weight,
and
increased
platelets
Chronic
Feeding
and
Carcinogenicity
in
Rats
41094101
41853701
42891201
Chronic
RfD
=
0.
0047
mg/
kg/
day
Chronic
Population
Adjusted
Dose
(cPAD)
=
0.
0016
mg/
kg/
day
cPAD
=
RfD/
FQPA
Safety
Factor.
6
Table
2.
Community
Harvest
of
Traditional
Foods
and
total
HCH
residues.

Traditional
Food
Total
HCH
Residues
(ng/
g)
Community
1
Harvest
(grams/
person/
day)
Community
2
Harvest
(grams/
person/
day)
Community
3
Harvest
(grams/
person/
day)

Polar
Bear
10
9
26
16
Seal
215
39
500
46
Whale
391
697
­­­­
271
Walrus
20
­­­­
22
315
Caribou
1
123
103
221
Moose
9
­­­­
81
Muskox
2
13
­­­­

Dall
Sheep
4
20
­­­­

Salmon
26
28
116
Arctic
Char
6
­­­­
10
Lake
Trout
3
100
­­­­

Arctic
Grayling
3
6
­­­­
6
Whitefish
20
­­­­
14
19
Cod
Residue
from
flesh
used

348
ng/
g
­­­­
18
ooligan
Smelt
­­­­
10
17
Herring
­­­­
22
Cisco
1
39
8
19
Goose
1
14
15
14
Duck
7
­­­­
12
Berries
10
­­­­
15
Total
HCH
Exposure
282,065
ng/
day
130,045
ng/
day
128,879
ng/
day
7
Table
3.
Assumed
Total
Dietary
Intake
of
Lindane
(gamma­
HCH)
and
Estimated
Risk
for
Indigenous
Children
16
yrs.
old.

%TotalHCHwhichis
Lindane
Community
1
(mg/
kg/
day)/%
cPAD
a
Community
2
(mg/
kg/
day)/%
cPAD
Community
3
(mg/
kg/
day)/%
cPAD
3%
Lindane
0.
00045/
28
0.00021/
13
0.00021/
13
15%
Lindane
0.
0022/
138
0.0010/
65
0.0010/
65
a
Example
calculation:
Exposure
=
0.
282
mg/
day
*
0.
15
or
0.
03
*
0.
53
/
10
kg
=
0.
0022
mg/
kg/
day
(15%
lindane)
or
0.00045
mg/
kg/
day
(3%
lindane).

Table
4.
Assumed
Total
Dietary
Intake
of
Lindane
(gamma­
HCH)
and
Estimated
Risk
for
Indigenous
Children
712
yrs.
old.

%TotalHCHwhichis
Lindane
Community
1
(mg/
kg/
day)/%
cPAD
a
Community
2
(mg/
kg/
day)/%
cPAD
Community
3
(mg/
kg/
day)/%
cPAD
3%
Lindane
0.
0002/
10
0.00007/
4
0.
00007/
4
15%
Lindane
0.
0008/
48
0.0004/
22
0.0004/
22
a
Example
calculation:
Exposure
=
0.
282
mg/
day
*
0.
15
or
0.
03
*
0.
53
/
29
kg
=
0.
0008
mg/
kg/
day
(15%
lindane)
or
0.0002
mg/
kg/
day
(3%
lindane).

Table
5.
Assumed
Total
Dietary
Intake
of
Lindane
(gamma­
HCH)
and
Estimated
Risk
for
Indigenous
Adult
Males.

%TotalHCHwhichis
Lindane
Community
1
(mg/
kg/
day)/%
cPAD
a
Community
2
(mg/
kg/
day)/%
cPAD
Community
3
(mg/
kg/
day)/%
cPAD
3%
Lindane
0.
00012/
8
0.
000056/
3
0.
000055/
3
15%
Lindane
0.
00060/
38
0.00028/
17
0.00027/
17
a
Example
calculation:
Exposure
=
0.
282
mg/
day
*
0.
15
or
0.
03
/
70
kg
=
0.
0006
mg/
kg/
day
(15%
lindane)
or
0.0001
mg/
kg/
day
(3%
lindane).

Table
6.
Assumed
Total
Dietary
Intake
of
Lindane
(gamma­
HCH)
and
Estimated
Risk
for
Indigenous
Adult
Females.

%TotalHCHwhichis
Lindane
Community
1
(mg/
kg/
day)/%
cPAD
a
Community
2
(mg/
kg/
day)/%
cPAD
Community
3
(mg/
kg/
day)/%
cPAD
3%
Lindane
0.
00014/
9
0.
000065/
4
0.
000064/
4
15%
Lindane
0.
00071/
44
0.00033/
20
0.00032/
20
a
Example
calculation:
Exposure
=
0.
282
mg/
day
*
0.
15
or
0.
03
/
60
kg
=
0.
0007
mg/
kg/
day
(15%
lindane)
or
0.0001
mg/
kg/
day
(3%
lindane).
8
Table
7.
Assumed
Total
Dietary
Intake
of
Lindane
(gamma­
HCH)
and
Estimated
Risk.

Population
Subgroup
Body
Weight
(kg)
Estimated
Lindane
Exposure
(mg/
kg/
day)
%cPAD
Adult
male
70
0.
000055
­
0.
0006
3­
38
Adult
female
60
0.
000064
­
0.
00071
4­
44
Children
(1­
6
yrs)
10
0.
0002
­
0.
0022
13­
138
Children
(7­
12
yrs.)
29
0.
00007­
0.0008
4­
48
References:

1
Heller,
C.,
1966.
Meat
Consumption
at
Three
Northern
Eskimo
Villages.
Environment
of
the
Cape
Thompson
Region,
Alaska.
Wilimovsky,
Norman,
&
Wolfe,
John,
Editors.
United
States
Atomic
Energy
Commission.
pp.
1109­
1111.

cc
:
Chem
F,
Chron
F.
Morton
RDI:
Team:
3/
27/
01;
SVH:
4/
17/
02
TM,
Thurston
Morton,
Rm.
816D
CM2,
305­
6691,
mail
code
7509C
