1
MEMORANDUM
3/
4/
05
SUBJECT:
Product
Chemistry
and
Environmental
Fate
Science
Chapters
of
Hexachlorobenzene(
HCB)
for
Pentachlorophenol
RED
(
PC
Code:
063001)

FROM:
A.
Najm
Shamim,
Ph.
D.,
Chemist,
Team
2
Risk
Assessment
and
Science
Support
Branch
Antimicrobials
Division(
7510C)

THRU:
Nader
Elkassabany,
Ph.
D.,
Acting
Team
Leader,
Team
2
Risk
Assessment
and
Science
Support
Branch
Antimicrobials
Division(
7510C)

TO:
Norm
Cook,
Chief
Risk
Assessment
and
Science
Support
Branch
Antimcirobials
Division(
7510C)

DP
Barcodes:
D272986,
D272988
MRID#:
N/
A
Attached
please
find
the
following
documents
for
the
completed
product
chemistry
and
environmental
fate
science
chapters
for
Hexachlorobenzene(
HCB).

1.
Final
Science
Chapter
on
Product
Chemistry
of
HCB
(
A.
Najm
Shamim)
2.
Final
Bibliography
of
HCB
Product
Chemistry
Science
Chapter
(
A.
Najm
Shamim)
3.
Final
Science
Chapter
on
Environmental
Fate
Chemistry
of
HCB
(
A.
Najm
Shamim)
4.
Final
Bibliogrpahy
of
HCB
Environmental
Fate
Chemistry
Science
Chapter
of
HCB
(
A.
Najm
Shamim)
The
documents
were
peer­
reviewed
by
Bob
Quick,
Chemist,
Risk
Assessment
and
Science
Support
Branch
This
is
the
final
Draft
of
these
documents
and
concurrence
and
sign­
off
are
requested.
2
SCIENCE
CHAPTER
ON
THE
PRODUCT
CHEMISTRY
OF
HEXACHLOROBENZENE
(
HCB)

I.
EXECUTIVE
SUMMARY
Hexachlorobenzene
is
not
a
naturally
occurring
compound
and
there
is
no
evidence
that
Hexachlorobenzene
(
HCB)
is
commercially
manufactured
in
the
United
States.
In
1982,
the
import
level
of
HCB
into
the
USA
was
about
38,000
lbs.
It
is
present
in
the
environment
due
to
numerous
emission
processes
as
well
as
due
to
the
manufacturing
processes
of
some
pesticides
where
it
is
present
as
a
micro
contaminant
(
see
below).
Based
on
the
draft
Emission
Inventory
Data
for
Section
112(
C)(
6)
Pollutants,
total
emission
of
HCB
into
the
environment
due
all
possible
emission
processes
was
estimated
to
be
about
2.3
tons/
year.
1
HCB
was
widely
used
as
a
pesticide
until
1984.
The
total
amount
stored
on
site
as
a
by­
product
or
impurity
ranges
from
0.15
to
1.52
million
ponds
per
year
.2
From
1987
to
1993,
based
on
EPA's
Toxic
Release
Inventory
(
TRI),
the
HCB
releases
to
the
environment
(
land
and
water)
were
estimated
to
be
approximately
1,
287
lbs.
Most
of
the
HCB
migrated
to
aqueous
medium.
3
The
following
table
provides
the
maximum
percentages
of
hexachlorobenzene
present
as
an
impurity
in
the
manufacturing
of
pesticides.
It
should
be
noted
that
all
the
pesticides
listed
are
agricultural
pesticides
except
for
pentachlorophenol
which
is
mainly
used
as
a
wood
preservative.

Pesticide
Maximum
Impurity
(%)
1
Atrazine
0.0017
Clopyralid
0.0008
Chlorothanil
0.05
Chlorpyrifos­
methyl
a___

Dacthal
(
DCPA)
0.30
Endosulfan
0.000075
Pentachloronitrobenzene
0.05
Pentachlorophenol(
PCP)
0.0075b
Picloram
0.01
Simazine
0.002
Notes:
a.
No
data
were
available
b.
The
Wood
Preservative
manufacturers
and
the
Agency
made
an
agreement
(
DCI,
1984)
that
the
industry
will
provide
analytical
data
for
PCP
manufacture
and
identify
some
of
the
contaminants
including
HCB
in
each
batch
that
would
be
analyzed
and
reported
to
the
Agency
every
month
as
monthly
reports.
This
agreement
was
made
due
to
the
Agency's
concern
about
the
microcontaminants
polychlorinated
dioxins,
polychlorinated
dibenzofurans
and
hexachlorobenzene.
3
II.
PRODUCT
CHEMISTRY:

a.
Manufacture:

Since
HCB
is
not
manufactured
in
the
United
States,
no
procedure
for
the
synthesis
of
HCB
was
submitted.

b.
Physical
Chemistry
Assessment:

Chemical
Name:
Hexachlorobenzene
Common
Names/
Trade
Names:
HCB,
Perchlorobenzene,
Anticarrie,
Buntcure
Bunt­
no­
more,
Granero,
Rest­
Q
CAS
#:
118­
74­
1
Molecular
Formula:
C
6
Cl
6
Molecular
Weight:
284.78
m.
p.
227
o
C
4
b.
p.
318
o
C
5
Density
1.56
(
23.6
o
C).
6
Water
Solubility:
0.006
g/
ml
(
25
o
C)
7
Vapor
Pressure:
1.1
x
10­
5
mm
Hg
(
25
o
C)
7
Henry
Law
Constant(
Log
K
P):
5.07
(
Calculated)
8
Bioaccumulation
(
Log
K
OW):
6.18
9
Bioconcentration
Factor
(
Log
BCF):
4.37,
3.89
(
Fathead
Minnow)
10
Sorption
Partition
Coefficient
Log
K
OC:
6.08
(
Calculated)
11
4
REFERENCES
FOR
PRODUCT
CHEMISTRY
OF
HEXACHLOROBENZENE
1.
Schmidt­
Bleek,
F.,
Haberland,
W.,
Klien,
A.
W.,
Caroli,
S.
1982
Steps
Towards
Environmental
Hazard
Assessment
of
New
Chemicals.
Chemosphere
11:
383­
416
2.
Bysshe
S.
E.,
1982
Bioconcentration
Factor
In
Aquatic
Organisms.
In:
The
Handbook
of
Chemical
Property
Estimation,
Eds:
W.
J.
Lyman,
W.
J,
Reehl,
W.
F.,
and
Rosenblatt,
D.
H.,
Chapter
5,
Ann
Arbor
Science,
Ann
Arbor,
Michigan.

3.
Mabey,
W.,
Smith,
J.
H.,
Podoll,
R.
T.,
Johnson,
H.
L.,
Chou,
T.
W.,
Gate,
J,
Waight­
Patridge,
I,
Jaber,
H.,
and
Vandenber,
D.
1982
Aquatic
Fate
Process
for
Organic
Priority
Pollutants
US
EPA
Report
No.
440/
4­
81­
14.

4.
Mackay,
D.,
and
Shiu,
W.
Y.
1981
A
Critical
Review
of
Henry's
Law
Constants
for
Chemicals
of
Environmental
Interest.
J.
Phys.
Chem
Ref.
Data.
10:
1175­
1199.

5.
Mackay
D.,
Bobra,
A.
M.,
Chan,
D.
W.,
and
Shiu,
W.
Y.,
1982
Vapor
Pressure
Correlation
for
Low­
Volatility
Environmental
Chemicals.
Environ.
Sci.
Technol.
16:
645­
649.

6.
Neely,
W.
B.,
Branson,
D.
R.,
and
Blau,
G.
E.
1974
Partition
Coefficient
to
Measure
Bioconcentration
Potential
of
Organic
Chemicals
in
Fish.
Environ.
Sci
Technol.
8:
1113­
1115
.
7.
Toxicological
Profile
of
Hexachlorobenzene
1996.
US
Department
of
Human
Health.

9.
Fact
Sheet:
August
11,
1999.
US
EPA's
Office
of
Ground
Water
and
Drinking
Water,
http://
www.
epa.
gov/
OGWDW/
dhw/
t­
ose/
hcb.
html
9.
Verschueren
K.,
1983.
Handbook
of
Environmental
Data
of
Organic
Chemicals,
Van
Nostrands
Reinhold
Publishers,
New
York.

10.
Weast
R.
C.,
Ed.
1972.
Handbook
of
Chemistry
and
Physics,
53
rd.
Edition,
CRC
Press,
Cleveland
11.
Wolf,
J.
1998.
DP
Barcode
D243496.
A
Memo
For
Environment
Fate
and
Effects
Division,
US
EPA.
5
SCIENCE
CHAPTER
ON
ENVIRONMENTAL
CHEMISTRY
OF
HEXACHLOROBENZENE
I.
EXECUTIVE
SUMMARY
Hexachlorobenzene(
HCB)
is
not
registered
as
a
pesticide
and
as
such
the
Agency
does
not
have
a
database
for
the
environmental
fate
chemistry
of
hexachlorobenzene.
The
Agency
has
conducted
an
open
literature
search
and
for
this
science
chapter
it
has
used
the
fate
properties
as
reported
in
literature.
Some
of
these
properties
are
measured
and
some
are
estimated
based
on
various
fate
models.

Hexachlorobenzene
does
not
contain
any
hydrolyzable
hydrogen
and
hence
the
hydrolytic
half
life
has
not
ben
determined.
It
is
sparingly
soluble
in
water
and
has
a
tendency
to
volatilize
from
surface
water
and
water
columns.
From
earlier
studies
on
surface
waters,
the
photolytic
half
life
was
estimated
to
be
between
156
days
and
4.2
years.
While
in
ground
water,
its
photolytic
half
life
was
estimated
to
be
between
5.3
and
11.4
years.

Photooxidation
half
life
of
HCB
has
been
estimated
to
range
between
2.7
and
5.7
years.
It
is,
therefore,
a
highly
persistent
molecule
in
aqueous
systems.
The
half
life
HCB
in
soils
was
estimated
in
the
range
of
156
days
to
4.2
years.
The
biodegradation
half
life,
under
aerobic
conditions,
were
estimated
in
the
range
of
156
days
to
4.2
years
and
in
earlier
studies,
under
anaerobic
conditions,
it
was
estimated
in
the
ranges
from
10.6
years
to
23
years
approximately.
More
recently,
however,
it
has
been
found
that
under
anaerobic
conditions,
its
degradation
half
life
lies
between
13
and
18
days.
The
biodegradation
process
has
been
shown
to
takes
place
through
dechlorination
process.

It
has
high
binding
capacity
with
soils
and
hence
is
likely
to
be
immobile
in
soils.
However,
due
to
sorption
processes
that
take
place
in
soils,
it
possibly
can
migrates
into
ground
water.

Log
K
OW
of
HCB
has
been
estimated
and
also
experimentally
measured
and
it
is
around
6,
and
hence
it
is
likely
to
be
bioaccumulative.
In
fact,
HCB
has
been
shown
to
be
bioaccumulative
in
some
aquatic
organisms,
for
example,
for
rainbow
trout,
the
rate
of
bioaccumulation
is
224
days.
However,
the
depuration
rate
is
about
7
days.
More
recent
study
on
various
types
of
whales
similar
results
were
obtained
that
HCB
does
bioaccumulate
with
half
lives
in
hours
and
depuration
rate
studies
also
show
that
half
lives
are
in
hours.

HCB
is
a
stable,
persistent
molecule
in
water
but
breaks
down
under
anaerobic
condition
via
dechlorination
transformation
processes.
It
is
bioaccumulative
in
aquatic
biota
like
fish
and
whales
but
also
depurates
quickly.
It
is
not
likely
to
adversely
impact
the
aquatic
organisms.
It
is
binds
strongly
with
soils
but
through
sorption
processes
migrates
into
ground
water
and
sediments.
Based
on
surface
water
monitoring
data
the
Agency
has
recently
estimated
that
HCB
6
concentration
in
surface
water
is
not
likely
to
exceed
10
parts
per
trillion
(
0.01
µ
g/
L).
There
are
no
estimations
for
ground
water
concentrations
of
HCB.

Appendix
to
Environmental
Fate
Chemistry
In
1979
the
EPA
issued
a
document
on
Water­
Related
Environmental
Fate
of
129
Priority
Pollutants,
Volumes
I
&
II
1.
Volume
II
discussed
the
fate
of
hexachlorobenzene
in
the
environment.
In
the
absence
of
experimental/
measured
data
on
most
of
the
fate
studies
(
hydrolysis,
photolysis,
soil
aquatic
metabolism
etc.),
a
full
environmental
fate
assessment
could
not
be
carried
out.
The
document
recognized
a
few
important
characteristics
of
hexachlorobenzene
and
some
conclusions
were
drawn.
Some
of
the
conclusions
drawn
were:

"
Hexachlorobenzene
is
a
very
persistent
molecule
and
has
a
high
affinity
for
lipophilic
materials.
Sorption
and
bioaccumulation
are
expected
to
be
high.
It
is
bioaccumulative
but
does
not
appear
to
biomagnify
through
aquatic
food
chain.
Depuration
rate
is
high
although
log
K
OW
is
on
the
high
side.
HCB
found
in
the
aquatic
organisms
is
from
aqueous
medium
rather
than
dietary
sources.
Chemically
it
is
inert
at
room
temperature
and
in
the
presence
of
caustic
alkali
between
120
and
200
oC
it
produces
pentachlorophenolate.
No
data
for
birds
and
predators
of
fish
were
available."

It
should
be
noted
that
this
document
was
produced
when
HCB
was
used
as
an
agricultural
pesticide.
Subsequent
to
this
document
the
Office
of
Pesticide
Program
has
issued
a
number
of
documents
which
discuss
the
presence
of
HCB
as
an
impurity
in
various
pesticide
manufacturing
processes.
Some
experimentally
measured
data
are
available
on
some
environmental
fate
studies.
The
following
discussion
briefly
outlines
the
measured
and/
or
estimated
environmental
fate
and
transport
data.

Hexachlorobenzene
is
sparingly
soluble
in
aqueous
medium
has
a
tendency
to
volatilize
from
surface
water
easily
and
quickly.

1.
Abiotic:

a.
Hydrolysis:

Hexachlorobenzene
is
a
highly
polar
compound
and
contains
no
hydrogen.
Hydrolysis
is
not
likely
to
take
place.
Ellington
et
al.
,
in
19872
attempted
to
measured
K
h
(
hydrolysis
constant
for
HCB)
but
after
13
days
of
measurements
at
pHs
:
3,
7
and
11
at
85
o
C
,
K
h
was
estimated
to
be
zero.
7
Hexachlorobenzene
is
a
stable
and
highly
persistent
molecule
in
aquatic
settings
and
does
not
hydrolyze.
However,
it
has
a
tendency
to
volatalize
from
the
water
and
soil
surfaces.
It
is
likely
to
become
immobile
in
soils.
However,
due
to
sorption
processes
on
soil
surface,
it
shows
a
tendency
to
migrate
into
ground
water
and
result
in
ground
water
contamination.
It
is
stable
under
aerobic
conditions
but
under
anaerobic
conditions
its
half
lives
are
shorter
(
13­
18
days)
therefore
the
main
route
of
dissipation
would
possibly
be
through
sorption
to
soils
in
terrestrial
settings
and
to
sediments.
Because
of
high
binding
constants
with
soils,
hexacholorobenzene
may
possibly
accumulate
in
benthic
sediment
and
bioaccumulate
in
benthic
organisms.
Environmental
Fate
and
Effects
Division
(
EFED)
has
recently
determined
that,
based
on
the
monitoring
data,
it
is
unlikely
that
HCB
concentration
in
surface
water
would
exceed
10
ppt
(
0.01
µ
g/
L).
10
b.
Photolysis:

Half­
life
for
photoxidation
of
HCB
in
air
was
measured
to
be
between
156
days
and
4.2
years
days3.
A
high
degree
of
uncertainty
was
noted
in
this
measurement.
Another
photolysis
study,
however,
conducted
in
water
and
hexane
(
T.
Mill
and
W.
Hagg)
12
,
the
photolytic
half
life
was
found
to
be
close
to
90
days.
In
a
solvent
mixture
of
water:
acetonitrile
(
4:
1)
the
half
life
was
about
70
days.
The
same
study
concluded
that
if
the
efficiency
of
light
is
assumed
to
be
the
same
in
solvents
and
air
then
air
photolysis
half
life
would
be
about
80
days.
This
value
is
almost
half
of
the
reported
in
the
previous
study3
.
However,
it
is
stable
and
persistent
in
aqueous
and
nonaqueous
systems
as
well
as
on
soil
surfaces.

2.
Biotic:

J.
Beck
and
K.
E.
Hansen's
work4
has
shown
that
in
surface
water,
under
aerobic
conditions,
biodegradation
half
life
of
hexachlorobenzene
varied
between
2.7
and
5.7
years.
Under
aerobic
conditions
but
in
ground
water,
the
biodegradation
half
life
ranges
between
5.3
and
11.4
years.
A
soil
grab
sample
study,
under
aerobic
conditions
showed
that
hexachlorobenzene
metabolizes
in
the
range
of
2.7
and
5.7
years.

Recent
experiments
on
fathead
minnows
(
Pimephales
promelas)
and
worm
(
Lumbriculus
variegatus)
showed
that
hexachlorobenzene
partitioned
more
efficiently
into
sediment
than
into
these
biota
and
other
biota.
5
It
has
been
shown
that
polychlorinated
chemicals
have
a
tendency
to
dechlorinate
(
biotransform)
under
anaerobic
conditions.
Hexachlorobenzene
partially
dechlorinates
in
the
presence
of
biota.
6
A
study
conducted
on
the
dechlorination
of
hexachlorobenzene
and
other
chlorinated
benzenes,
carried
out
on
a
contaminated
estuarine
sediment
which
contained
an
enriched
culture,
showed
that
hexachlorobenzene
undergoes
reductive
dechlorination.
Using
a
pseudo
first
order
model,
it
was
observed
that
under
these
reductive
conditions,
the
half
life
of
hexachlorobenzene
is
2.5
days
and
all
of
hexachlorobenzene
is
converted
into
pentachlorobenzene
(
Pavlosthathis,
S.
G.,
and
Prytula,
M.
T.)
13
8
Under
anaerobic
microbial
conditions,
using
an
anaerobic
sewage
sludge,
in
the
concentration
range
of
2­
50
mg/
L,
hexachlorobenzene
dechlorinated.
When
HCB
concentrations
were
between
2.5
and
10
mg/
L,
complete
dechlorination
process
occurs
in
six
days.
This
phenomenon
was
observed
in
the
presence
of
1,
2,
3­
trichlorobenzene­
adapted
anaerobic
consortium
.
The
dechlorination
was
fastest
at
pH
7,
while
at
pHs
6,
8,
and
9,
and
dechlorination
occurs
between
13­
18
days.
The
reducing
conditions
(
anaerobic)
used
for
this
study
were:
sulfate
reducing,
denitrifying
and
methanogenic
conditions.
The
rates
of
dechlorination
were
the
same
under
these
three
conditions.
(
Yuan,
S.
Y.,
Su,
C.
J,
and
Chang,
B.
V.).
14
Under
anaerobic
conditions,
it
does
not
appear
stable.

Because
of
the
high
K
OC,
hexachlorobenzene
can
be
sorbed
with
soils
and
sediments
very
tightly
so
that
soils/
sediments
can
act
as
a
sink
for
molecules
like
hexachlorobenzene.
A
recent
report
has
identified
PCDDs,
PCDFs,
PCBs
and
HCB
in
the
sediment
samples
from
sites
located
in
Queensland
in
Northern
Australia.
This
report
is
interesting
as
there
are
no
industrial
activities
in
this
area.
No
direct
link
can
be
established
for
anthropogenic
origin
of
these
substances.
(
Muller,
J.
F,
Haynes,
D.,
McLachlan,
M.,
Bohme,
F.,
Will,
S.,
Shaw,
G.
R,
Mortimer,
M.,
Sadler,
R.,
and
Connell,
D.
W.)
15
Bioaccumulation:

A
few
values
are
reported
here
from
open
literature
for
some
aquatic
species:

Rainbow
trout:
>
224
days7
Subadult
rainbow
trout:
210
days
at
4
o
C
80
days
at
12
o
C
70
days
at
18
o
C
8
Worm
27
days
at
8o
C
Depuration
Rate
from
fish
~
7
days9
Recently,
analysis
of
marine
mammal
tissues,
specifically
seals,
pilot
whale,
harbor
porpoise,
white­
sided
dolphin,
begula
whale
and
bowhead
whale.
The
tissues
of
these
marine
mammals
have
been
archived
at
the
U.
S.
National
Biomonitoring
Specimen
Bank,
housed
in
National
Institute
of
Standards
and
Technology,
showed
the
presence
of
(
bioaccumulation)
of
hexachlorobenzene
and
also
some
trace
metals.
The
concentration
of
hexachlorobenzene
ranged
from
43
ng/
g
wet
weight
of
the
mammalian
tissue:
up
to
1070
ng/
g
in
Pilot
Whale
of
North
Atlantic
and
in
Harbor
Porpoise,
also
of
North
Atlantic.
(
Becker,
P.
R.,
Mackey,
E.
A.,
Demimarlp,
R.,
Schantz,
M.
M.,
Koster,
B.
J.,
and
Wise,
S.
A.)
16
Another
published
study
conducted
in
laboratory
conditions
on
the
bioaccumulation
of
hexachlorobenzene
(
and
Lindane)
in
tubicificid
sludgeworms
(
Oligochaeta)
indicate
the
two
types
of
worms:
T.
tubifex
and
L.
hoffmeistri
the
uptake
rate
constant
were
0.169
and
0.470
and
0.589/
h
and
0.458/
h
respectively
which
when
converted
to
half
lives
measured
at
4.1
hour
and
1.4
hours.
The
depuration
rate
constants
were
biphasic
and
in
the
first
phase
the
rate
constants
9
were
0.037/
h
and
0.047/
h
which
translate
into
19
hours
to
15
hours
while
in
the
second
phase,
the
rate
constants
were
0.004
and
0.002
which
gave
half
lives
as:
173
hours
and
347
hours.
(
Egeler,
P.,
Rombke,
J.,
Meller,
M.,
Knacker,
Th.,
Franke,
C.,
Studinger,
G.
And
Nagel,
R.)
17
10
REFERENCES
FOR
ENVIRONMENTAL
FATE
CHEMISTRY
SCIENCE
CHAPTER
1.
Atkinson,
R.
1987
A
Structure
­
Activity
Relationship
For
The
Estimation
of
Rate
Constants
for
the
Gas
Phase
Reaction
of
OH
Radicals
with
Organic
Compounds.
International
Journal
of
Chemical
Kinetics.
19:
799­
828.

2.
Beck,
J.,
and
Hansen
K.
E.
,
1974.
The
Degradation
of
Quintozene,
Pentachlorobenzene,
Hexachlorobenzene
and
Pentachloroaniline
in
Soil.
Pesticide
Science.
5:
41­
48
3.
Becker,
P.
R.,
Mackey,
E.
A.,
Demimarlp,
R.,
Schantz,
M.
M.,
Koster,
B.
J.,
and
Wise,
S.
A.
1997.
Concentrations
of
Chlorinated
Hydrocarbons
and
Trace
Elements
in
Marine
Mammal
Tissues
Archives
in
the
US.
National
Biomonitoring
Specimen
Bank.
Chemosphere.
34(
9/
10):
2067­
2098
4.
Egeler,
P.,
Rombke,
J.,
Meller,
M.,
Th.
Frank,
C.,
Studinger,
G.,
and
Nagel,
R.
1997.
Bioaccumulation
of
Lindane
and
Hexachlorobenzene
by
Tubificid
Sludgeworms
(
Oligochaeta)
Under
Standardized
Laboratory
Conditions.
Chemosphere.
35(
4):
835­
852
5.
Ellington,
J.
J.,
Stancil,
F.
E.,
and
Payne,
W.
D.
1987
Measurement
of
Hydrolysis
Rate
Constants
for
Evaluation
of
Hazardous
Waste
Land
Disposal.
Volume
I:
Data
on
32
Chemicals.
US
EPA­
600/
3­
86­
043
6.
B.
Z.
Fathepure
et
al.,
1988.
Appl.
Environ.
Microbiol.
54:
2976­
2980
7.
Mill,
T.,
and
Haag,
W.
1985.
The
Environmental
Fate
of
Hexachlorobenzene
Hexachlorobenzene:
Proceedings
of
an
International
Symposium,
International
Agency
on
Cancer
Research.,
Held
at
Lyon,
France,
Scientific
Publication
No.
77,
Eds:
Morris,
C.
R.,
and
Cabral,
J.
R.
P.

8.
Muller,
J.
F.,
Haynes,
D.,
McLachan,
M.,
Bohme,
F,
Will,
S.,
Shaw,
G.
R.,
Sadler,
R.,
and
Connell,
D.
W.
1999.
PCDDs,
PCDFs,
PCBs,
and
HCB
in
Marine
and
Estuarine
Sediments
From
Queensland,
Australia.
Chemosphere.
39(
10):
1707­
1721
9.
Neely,
W.
B.,
1980
A
Method
of
Selecting
the
Most
Appropriate
Environmental
Experiments
on
a
New
Chemical.
In:
Dynamic,
Exposure
and
Hazard
Assessment
of
Toxic
Chemicals,
Ed:
R.
Haque.
Ann
Arbor
Sci.
Publications,
Ann
Arbor,
Michigan.

10.
Niimi,
A.
J.,
and
Cho
C.
Y,
1980.
Uptake
of
Hexachlorobenzene(
HCB)
from
Feed
by
Rainbow
Trout
(
Salmo
Gairdneri)
Bull.
Environ.
Toxicol.
24:
834­
837.

11.
Niimi,
A.
J.,
and
Palazo,
V.
1985.
Temperature
Effect
on
the
Elimination
of
Pentachlorophenol,
Hexachlorobenzene
and
Mirex
by
Rainbow
Trout
(
Salmo
Gairdenri)
Water
Research.
19(
2):
205­
207
11
12.
Pavlosthahis,
S.
G.,
and
Prytula,
M.
T.,
2000
Kinetics
of
the
Sequential
Microbial
Reductive
Dechlorination
of
Hexachlorobenzene.
Environmental
Science
and
Technology.
34:
4001­
4009.

13.
G.
S.
Schuytema
et
al.,
1990.
Arch
Environ.
Contam.
Toxicol.,
1:
1­
9
14.
US
EPA
Document:
1979
Water
Related
Environmental
Fate
of
129
Priority
Pollutants,
Volumes
I
and
II,
EPA­
440/
4­
79­
29a,
029b.

15.
Wolfe,
J.,
April
1998.
DP
Barcode:
D243496.
A
Memo
on
Drinking
Water
Assessment
of
HCB
and
PCB.

16.
Yuan,
S.
Y.,
Su,
C.
J.,
and
Chang,
B.
V.
1999.
Microbial
Dechlorination
of
Hexachlorobenzene
in
Anaerobic
Sewage
Sludge.
Chemosphere.
38(
5):
1015­
1023
