June
25,
1996
TSCA
SECTION
4
FINDINGS
FOR
21
HAZARDOUS
AIR
POLLUTANTS
A
Supporting
Document
for
Proposed
Hazardous
Air
Pollutants
(
RAPs)

Test
Rule
For
specific
information
regarding
this
document,
contact:

Gary
E.
Timrn
Chemical
Control
Division
Office
of
Pollution
Prevention
and
Toxics
(
202)
260
 
1859
RECEIVED
OPPT
NCIC
2003
MAR11
5:
03PM
OPPT­
2003­
0010­
0021
The
testing
proposed
in
the
HAP5
rule
is
based
on
the
authority
of
section
4(
a)
of
the
Toxic
Substances
Control
Act
(
TSCA),
15
U.
S.
C.
2601
et
p~
g.
The
U.
S.
Environmental
Protection
Agency
(
EPA)
interprets
TSCA
section
4(
a)
to
mean
that
EPAs
authority
to
require
testing
under
TSCA
section
4(
a)
(
1)
(
A)
and
(
B)
is
predicated
on
the
data
insufficiency
and
testing
is
necessary"
findings
required
under
TSCA
section
4(
a)
(
1)
(
A)
(
ii)
and
(
iii)
and
4(
a)
(
1)
(
B)
(
ii)
and
(
iii).
Discussions
of
the
statutory
framework
for
TSCA
section
4(
a)
findings
are
provided
in
EPAU5
first
and
second
proposed
test
rules,
which
were
published
in
the
Federal
Register
notices
of
July
18,
1980
(
45
FR
48524)
and
June
5,
1981
(
46
FR
30300)
.
Thus
once
EPA
has
made
a
finding
under
TSCA
section
4(
a)
(
1)
(
A)
(
i)
that
a
chemical
substance
may
present
an
unreasonable
risk
of
injury
to
health
or
the
environment
or
a
finding
under
section
4(
a)
(
1)
(
B)
(
i)
that
a
chemical
substance
is
or
will
be
produced
in
substantial
quantities,
and
either
it
may
enter
the
environment
in
substantial
quantities
or
there
may
be
substantial
or
significant
human
exposure
to
the
chemical
substance,
EPA
may
require
any
type
of
health
or
environmental
effects
testing
necessary
to
address
unanswered
questions
about
the
effects
of
the
chemical
substance.
EPA
need
not
limit
the
scope
of
testing
required
to
the
factual
basis
for
the
section
4(
a)
(
1)
(
A)
(
i)
or
(
B)
(
i)
findings.
As
explained
in
EPAs
statement
of
policy
for
making
findings
under
TSCA
section
4(
a)
(
1)
(
B)
in
the
Federal
Register
of
May
14,
1993
(
EPA,
l993a,
pp.
28736,

28738)
Essentially,
under
TSCA
section
4(
a)
(
1)
(
B)
(
i),
EPA
may
require
health
effects
testing
even
if
it
has
only
made
a
finding
that
there
is
or
may
be
substantial
entry
into
the
environment
of
a
substance,
or
require
environmental
effects
testing
even
if
it
has
only
made
a
finding
that
there
is
or
may
be
substantial
or
significant
human
exposure
to
a
substance.
Clauses
(
I)
and
(
II)
of
section
4(
a)
(
1)
(
B)
(
i)
can
be
interpreted
as
mutually
exclusive.
.
.
.
Either
finding
is
sufficient
to
require
testing,
so
long
as
EPA
finds
that
data
relevant
to
a
determination
of
whether
a
substance
does
or
does
not
present
an
unreasonable
risk
of
injury
to
health
or
the
environment
are
insufficient
and
that
testing
is
necessary
to
develop
such
data.

In
articulating
the
policy
for
making
findings
under
section
TSCA
4(
a)
(
1)
(
B)
(
frequently
described
as
the
"
B
policy),
EPA
has
defined
"
substantial
production"
as
annual
aggregate
production
of
1
million
pounds
or
2
more
and
"
substantial
release"
as
an
annual
release
into
the
environment
of
1
million
pounds
or
10%
of
production,
whichever
is
lower.
Id.
at
28746.
These
definitions
apply
to
the
terms
"
substantial
production"
and
"
substantial
release"
as
used
in
this
document.
(
As
explained
in
Unit
III.
C.
of
the
preamble
to
the
proposed
rule,
all
chemical
substances
proposed
for
testing
in
this
proposed
rule
are
emitted
into
the
atmosphere
in
the
amount
of
50
tons
per
year
or
more
according
to
the
Toxics
Release
Inventory
(
TRI)
.)

In
its
final
B
policy
statement,
EPA
defined
"
substantial
human
exposure"
as
an
annual
exposure
of
100,000
members
of
the
general
population,

10,000
consumers,
or
1,000
workers.
Id.
In
proposing
the
B
policy
on
July
15,

1991
(
EPA,
l99la
pp.
32294,
32297)
,
EPA
explained
its
use
of
different
exposure
levels
in
this
way:

EPA
believes
that
the
different
numerical
thresholds
for
workers,

consumers,
and
the
general
population
are
necessary
to
reflect
the
inherent
differences
in
each
probable
exposure
scenario
(
e.
g.,
workers
generally
are
exposed
on
a
more
routine
or
direct
basis
than
consumers,

and
consumers
are
generally
exposed
on
a
more
direct
basis
than
the
general
public)
As
a
general
matter,
EPA
has
found
that
workers
tend
to
be
subject
to
routine
or
episodic
exposure
over
a
long
period
of
time.
Thus,

exposure,
to
be
considered
substantial,
does
not
have
to
be
as
widespread
for
workers
as
for
consumers
or
the
general
population.
.

Under
TSCA,
EPA
has
generally
interpreted
the
term
"
significant"

as
relating
to
the
nature
or
importance
of
exposure.
EPA
therefore
is
proposing
to
interpret
"
significant"
as
referring
to
the
nature
of
the
exposure.
EPA
believes
that
if
the
nature
of
some
exposure
is
sufficiently
direct,
large
or
prolonged,
even
if
the
number
of
people
exposed
is
not
"
substantial,
there
is
a
need
to
develop
data
on
the
chemical
because,
on
the
basis
of
the
data,
EPA
may
take
some
risk
management
action
to
control
the
exposure.

Consistent
with
this
policy,
the
findings
below
regarding
substantial
human
exposure
use
different
numerical
thresholds
for
workers,
consumers,
and
the
general
population.

A.
1,1
 
Biphenyl
(
92
 
52
 
4)

EPA
is
proposing
testing
of
1,1­
biphenyl
under
the
authority
of
sections
4(
a)
(
1)
(
A)
and
4(
a)
(
1)
(
B)
of
TSCA.

3
and
spleen
of
rats
and
mice
with
90­
day
exposures
up
to
1,000
ppm
(
NTP,

l992c)
,
but
an
evaluation
of
immune
function
was
not
performed.
NTP
has
conducted
an
inhalation
chronic
assay,
but
the
final
report
is
not
yet
available
(
NTP,
1996)
.
No
data
were
located
on
the
respiratory
sensory
irritation
of
ethylbenzene.

4.
Section
4(
a)
(
1)
(
A)
(
iii)
and
4(
a)
(
1)
(
B)
(
iii)
findings.
Therefore,

EPA
believes
that
the
testing
of
ethylbenzene
is
necessary
to
develop
data
for
acute
toxicity,
developmental
toxicity,
reproductive
toxicity,
neurotoxicity
,
immunotoxicity,
and
respiratory
sensory
irritation.
EPA
believes
that
this
testing
is
needed
to
determine
if
the
manufacture,
processing,
use,
and
disposal
of
ethylbenzene
does
or
does
not
present
an
unreasonable
risk
of
injury
to
human
health
from
inhalation
exposure.

I.
Ethylene
Dichloride
(
107­
06­
2)

EPA
is
proposing
testing
of
ethylene
dichloride
(
EDC)
under
the
authority
of
sections
4(
a)
(
1)
(
A)
and
4(
a)
(
1)
(
B)
of
TSCA.

1.
Section
4(
a)
(
1)
(
A)
(
i)
findings.
EPA
believes
that
the
manufacture,
processing,
and
use
of
EDC
may
present
an
unreasonable
risk
of
injury
to
health.
Several
studies
indicated
high
mortality
rates
following
inhalation
exposure.
Hofmann
at
al.
exposed
rats,
guinea
pigs,
rabbits,
and
cats
to
100
and
500
ppm
of
EDC
for
6
hours/
day,
5
days
per
week
for
6
weeks.

Mortality
was
high
in
all
species
exposed
to
500
ppm.
Necropsy
revealed
lesions
in
the
liver,
kidney,
adrenals,
heart,
and
lungs
(
Hofmann
et
al.,

1971)
.
Maltoni
et
al.
reported
a
high
incidence
of
mortality
of
rats
exposed
to
250
ppm
of
EDC
in
an
carcinogenicity
study,
forcing
him
to
reduce
the
high
exposure
to
150
ppm
after
10
weeks
(
Maltoni
et
al.,
1980).
Mortality
was
reported
at
300
ppm
in
a
study
of
developmental
toxicity
(
Shell
Oil
Company,

1979)

The
carcinogenicity
of
EDC
has
been
demonstrated
in
rats
and
mice
by
gavage
exposure
(
NCI,
l978a),
but
not
by
inhalation
(
Maltoni
et
al.,
1980).

Male
rats
had
a
significantly
increased
incidence
of
forestomach
squamous­
cell
24
carcinomas
and
circulatory
system
hemangiosarcomas
in
the
NCI
study.
Female
rats
and
mice
were
observed
to
have
significant
increases
in
mammary
adenocarcinoma
incidence.
Mice
of
both
sexes
developed
alveolar/
bronchiolar
adenomas,
females
developed
endometrial
stromal
polyps
and
sarcomas,
and
males
developed
hepatocellular
carcinomas
(
NCI,
l978a)
.
Based
on
the
exposure
discussed
below
and
these
concerns,
EPA
finds
that
EDC
may
present
an
unreasonable
risk
of
injury
to
human
health.

2.
Section
4(
a)
(
1)
(
B)
(
i)
findings.
(
i)
EPA
believes
that
EDC
is
produced
in
substantial
quantities.
EDC
production
in
1992
was
14.3
billion
pounds
(
CMR,
l992f).

(
ii)
EPA
believes
that
there
is
or
may
be
substantial
human
exposure
to
EDC.
EDC
is
currently
used
as
a
chemical
intermediate
principally
in
the
synthesis
of
vinyl
chloride
monomer,
as
a
solvent
in
closed
systems,
and
in
the
synthesis
of
vinylidene
chloride,
l,
l,
l­
trichloroethane,

trichloroethylene,
tetrachloroethylene,
aziridines,
and
ethylene
diamines
(
ATSDR,
1992)
.
NIOSH
estimated
that
77,111
workers
were
potentially
exposed
to
EDC
in
1980
in
the
apparel
and
textile
industries,
chemical
and
allied
products
industries,
business
services,
and
petroleum
and
coal
products
industries
(
NIOSH,
1989)

The
greatest
source
of
exposure
to
EDC
for
the
general
population
is
inhalation
of
contaminated
air.
Atmospheric
exposure
to
EDC
varies
greatly
from
one
location
to
another.
Mean
levels
as
high
as
27.5
ppb
have
been
monitored
near
production
and
use
facilities
in
Lake
Charles,
Louisiana.
Most
locations
have
EDC
concentrations
of
0.5
ppb
or
less
(
EPA,
1985)

(
iii)
EPA
believes
that
there
is
substantial
environmental
release
of
EDC.
The
1993
TRI
indicates
2.3
million
pounds
of
EDC
were
released
to
the
atmosphere
(
EPA,
1995)

3.
Section
4(
a)
(
1)
(
A)
(
ii)
and
4(
a)
(
1)
(
B)
(
ii)
findings.
EPA
believes
that
there
are
inadequate
data
and
experience
to
determine
or
predict
the
effects
on
human
health
from
the
manufacturing,
processing,
and
use
of
EDC.

An
inhalation
developmental
toxicity
study
was
conducted
in
rabbits
at
100
and
300
ppm
(
Shell
Oil
Company,
1979)
.
Despite
the
use
of
only
two
exposure
levels,
EPA
regards
this
study
as
acceptable.
Maternal
toxicity
was
observed
25
at
both
treatment
levels.
No
developmental
effects
were
noted.
However,
the
inhalation
developmental
toxicity
test
in
rats
is
inadequate
(
Shell
Oil
Company,
1979)
.
Again,
only
two
exposure
levels
were
used
(
100
and
300
ppm)

However,
maternal
toxicity
was
so
severe
at
the
highest
dose
level
that
many
females
died
and
no
pups
were
born
to
the
surviving
dams.
Although
no
maternal
or
developmental
effects
were
seen
at
100
ppm,
too
few
pregnant
animals
were
used
at
this
dose
level
to
conclude
that
this
was
an
acceptable
negative
study.
A
one­
generation
reproductive
inhalation
study
was
conducted
in
rats
at
25,
75,
and
150
ppm
(
Murray
et
al.,
1980)
and
a
multi­
generation
drinking
water
test
in
mice
was
conducted
at
30,
90,
and
290
mg/
L
(
Lane
et
al.,
1982)
.
Both
studies
are
deficient,
however,
in
that
neither
identified
an
effect
level.

The
acute
tests
are
not
adequate
to
determine
portal
of
entry
effects
and
extra­
respiratory
effects.
The
respiratory
irritation
study
by
DuPont
was
conducted
in
rats
at
inhalation
exposures
ranging
from
640
to
12,000
ppm
for
only
10
minutes,
exposed
only
males,
did
not
evaluate
histopathology,
and
used
too
few
animals
(
DuPont,
1982)
.
Union
Carbide
exposed
rats,
mice,
and
rabbits
to
200
ppm
of
EDC
for
1
hour
(
Union
Carbide
Corporation,
1987)
.
This
study
was
inadequate
because
it
was
conducted
at
only
one
dose
level
and
only
limited
endpoints
were
evaluated.
Similarly,
Carpenter
et
al.
exposed
rats
by
inhalation
to
1,000
ppm
of
EDC
for
4
hours
(
Carpenter
et
al.,
1949).
Spencer
et
al.
exposed
rats
by
inhalation
to
six
different
concentrations
ranging
from
300
to
3,000
ppm
over
a
0.5­
to
8­
hour
period
(
Spencer
et
al.,
1951).
The
lack
of
adequate
reporting
precludes
the
further
evaluation
or
use
of
this
study.
Heppel
et
al.
exposed
rats,
mice,
guinea
pigs,
rabbits,
cats,
hogs,

and
raccoons
by
inhalation
at
1,500
and
3,000
ppm
over
a
range
of
times
varying
between
1.5
and
7
hours
(
Heppel
et
al.,
1945)
.
The
Heppel
et
al.

study
was
also
reported
as
a
summary
that
precludes
its
full
evaluation
and
use.
Several
inadequate
subchronic
studies
were
found
in
the
literature.

Lioia
and
Elmino
exposed
rabbits
to
3,000
ppm
of
EDC
by
inhalation
for
90
days
(
Lioia
and
Elmino,
1959)
.
This
study
was
conducted
at
only
one
exposure
level
and
does
not
report
the
use
of
controls.
Hofmann
et
al.
exposed
rats,
guinea
pigs,
rabbits,
and
cats
to
100
and
500
ppm
of
EDC
for
6
hours/
day,
5
days/
week
26
for
6
weeks
(
Hofmann
et
al.,
1971)
.
This
study
exposed
animals
to
only
two
concentrations
for
only
6
weeks.
High
mortality
was
found
at
the
high
exposure
level
and
no
toxic
effects
were
reported
at
the
low
exposure
level.

Intermediate
exposure
levels
should
be
studied
to
determine
the
effects
of
sublethal
concentrations.
A
second
study
by
Hofmann
exposing
rats,
guinea
pigs,
rabbits,
and
cats
to
500
ppm
of
EDC
for
13
weeks
followed
by
exposure
to
1,000
ppm
EDC
for
an
additional
13
weeks
produced
results
(
no
toxicity
at
500
ppm)
that
appear
at
odds
with
those
of
his
first
study
(
Hofmann
et
al.,
1971).

This
study
is
not
a
standard
subchronic
study.

Although
acute
studies
indicate
neurological
effects,
these
studies
are
inadequate
because
they
did
not
evaluate
the
appropriate
neurological
endpoints:
functional
observational
battery,
neuropathology,
and
motor
activity
(
Spencer
et
al.,
1951)
.
No
subchronic
neurotoxicity
studies
were
found.
No
data
were
located
for
respiratory
sensory
irritation.

4.
Section
4(
a)
(
1)
(
A)
(
iii)
and
4(
a)
(
1)
(
B)
(
iii)
findings.
Therefore,

EPA
believes
that
the
testing
of
EDC
is
necessary
to
develop
data
for
acute
toxicity,
subchronic
toxicity,
developmental
toxicity,
reproductive
toxicity
,
neurotoxicity,
and
respiratory
sensory
irritation.
EPA
believes
that
this
testing
is
needed
to
determine
if
the
manufacture,
processing,
and
use
of
EDC
does
or
does
not
present
an
unreasonable
risk
of
injury
to
human
health
from
inhalation
exposure.

J.
Ethylene
Glycol
(
107­
21­
1)

EPA
is
proposing
testing
of
ethylene
glycol
under
the
authority
of
TSCA
section
4(
a)
(
1)
(
B).

1.
Section
4(
a)
(
1)
(
B)
(
i)
findings.
(
i)
EPA
believes
that
ethylene
glycol
is
produced
in
substantial
quantities.
Ethylene
glycol
production
in
1992
was
7.4
billion
pounds
(
CMR,
l993a)

(
ii)
EPA
believes
that
there
is
or
may
be
substantial
human
exposure
to
ethylene
glycol.
Ethylene
glycol
is
widely
used
as
an
antifreeze
in
heating
and
cooling
systems,
a
de­
icing
agent
on
bridges
and
airport
runways,
and
a
solvent
in
the
paints
and
plastics
industry.
It
is
also
used
in
hydraulic
27
