UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON,
D.
C.
20460
April
3,
2003
OFFICE
OF
PREVENTION,
PESTICIDES
AND
TOXIC
SUBSTANCES
CERTIFIED
MAIL
#
7001
1140
0001
4913
6709
Dear
Registrant:

This
is
the
Environmental
Protection
Agency's
(
hereafter
referred
to
as
EPA
or
the
Agency)
Report
of
the
Food
Quality
Protection
Act
(
FQPA)
Tolerance
Reassessment
Progress
and
Risk
Management
Decision
(
TRED)
for
4­
Chlorophenoxyacetic
Acid
(
4­
CPA),
which
was
approved
on
April
3,
2003.
A
Notice
of
Availability
of
this
TRED
will
be
published
in
the
Federal
Register
(
FR).

The
Federal
Food,
Drug
and
Cosmetic
Act
(
FFDCA),
as
amended
by
FQPA,
requires
EPA
to
reassess
all
the
tolerances
for
registered
chemicals
in
effect
on
or
before
the
date
of
the
enactment
of
the
FQPA,
which
was
in
August
of
1996.
In
reassessing
these
tolerances,
the
Agency
must
consider,
among
other
things,
aggregate
risks
from
non­
occupational
sources
of
pesticide
exposure,
whether
there
is
increased
susceptibility
to
infants
and
children,
and
the
cumulative
effects
of
pesticides
with
a
common
mechanism
of
toxicity.
Once
a
safety
finding
has
been
made
that
aggregate
risks
are
not
of
concern,
the
tolerances
are
considered
reassessed.
A
reregistration
eligibility
decision
(
RED)
for
4­
CPA
was
completed
in
March
1995,
prior
to
FQPA
enactment.
Therefore,
the
tolerances
need
to
be
reassessed
to
meet
the
FQPA
standard.

The
pesticide
4­
CPA
is
used
indoors
to
restrict
root
growth
during
seed
germination
of
mung
beans.
The
only
exposure
anticipated
is
via
the
food
pathway.
There
is
no
exposure
expected
through
consumption
of
drinking
water
given
the
enclosed
nature
of
the
chemical's
use,
and
there
are
no
registered
residential
uses.
Therefore,
aggregating
exposures
from
the
food,
drinking
water,
and
residential
pathways
of
exposure
is
not
necessary.
As
a
result,
the
Agency
has
only
evaluated
the
dietary
(
food)
risk
associated
with
the
use
of
4­
CPA,
and
has
determined
that
there
is
a
reasonable
certainty
that
no
harm
to
any
population
subgroup
will
result
from
this
potential
exposure.
Therefore,
no
mitigation
measures
are
needed,
and
the
tolerances
established
for
residues
of
4­
CPA
in/
on
raw
agricultural
commodities
are
now
considered
reassessed
as
safe
under
§
408(
q)
of
the
FFDCA.

FQPA
requires
that
EPA
consider
"
available
information"
concerning
the
cumulative
effects
of
a
particular
pesticide's
residues
and
"
other
substances
that
have
a
common
mechanism
of
toxicity."
The
reason
for
considering
other
substances
is
because
of
the
possibility
that
lowlevel
exposures
to
multiple
chemical
substances
that
cause
a
common
toxic
effect
by
a
common
mechanism
could
lead
to
the
same
adverse
health
effect,
as
would
a
higher
level
of
exposure
to
any
of
the
other
substances
individually.
2
Although
the
Agency
compared
toxicities
of
other
chlorophenoxy
acetic
acids
to
4­
CPA
to
improve
the
hazard
characterization,
EPA
does
not
have,
at
this
time,
available
data
to
determine
whether
4­
CPA
has
a
common
mechanism
of
toxicity
with
other
substances.
For
the
purposes
of
this
TRED,
EPA
is
assuming
there
is
no
common
mechanism
of
toxicity,
and
that
the
tolerances
established
for
residues
of
4­
CPA
in/
on
raw
agricultural
commodities
are
considered
reassessed
as
safe
under
§
408(
q)
of
the
FFDCA.

The
Agency
also
reviewed
4­
CPA
to
determine
if
its
use
pattern
could
cause
adverse
impacts
on
endangered
and
threatened
species.
Approximately
20
pounds
of
4­
CPA
active
ingredient
(
ai)
are
used
per
year
for
indoor
treatment
of
mung
beans
at
a
single
production
facility.
Due
to
the
limited
usage
of
this
chemical
in
total
annual
pounds
used
and
geographic
area
used,
there
are
unlikely
to
be
risks
to
endangered
species
associated
with
4­
CPA.
Additionally,
waste
water
discharges
containing
4­
CPA
resulting
from
this
registered
use
are
subject
to
pre­
treatment
requirements
and
are
likely
to
be
significantly
diminished
through
this
process.
Any
residues
of
4­
CPA
leaving
the
production
facility
are
likely
to
be
further
reduced
(
if
not
eliminated)
at
a
publicly
owned
treatment
works
prior
to
entering
surface
water.
Therefore,
EPA
believes
that
the
exposures
and
risks
to
endangered
species
from
the
registered
use
of
4­
CPA
are
likely
to
be
low
and
not
of
concern
to
the
Agency.

The
Agency's
human
health
findings
for
the
plant
growth
regulator
4­
CPA
are
summarized
in
the
enclosed
human
health
risk
assessment.
The
risk
assessment
and
other
technical
support
documents
pertaining
to
the
4­
CPA
TRED
are
listed
in
Attachment
One
of
this
document
and
are
available
for
viewing
in
the
OPP
public
docket
and
on
the
Internet
at
http://
www.
epa.
gov/
edocket/.
The
4­
CPA
docket
ID
number
is
OPP­
2003­
0124.

The
tolerances
for
residues
of
4­
CPA
in/
on
raw
agricultural
commodities
are
for
the
parent
compound,
4­
CPA
per
se.
No
metabolites
or
degradates
are
included
in
the
tolerance
expression.
The
existing
tolerances
for
4­
CPA
have
been
reassessed.
One
tolerance
for
tomatoes
(
no
longer
supported
or
on
the
label)
will
be
revoked,
and
the
tolerance
for
mung
bean
sprouts
will
be
reduced
from
2.0
to
0.2
ppm
based
upon
previously
reviewed
and
accepted
residue
chemistry
studies.
No
maximum
residue
limits
(
MRLs)
for
4­
CPA
have
been
established
or
proposed
by
Codex.
Therefore,
there
are
no
international
compatibility
issues
with
respect
to
the
U.
S.
tolerances.
A
summary
of
the
reassessed
tolerances
for
residues
of
4­
CPA
are
found
in
Table
1.

Table
1.
Tolerance
Reassessment
Summary
for
4­
CPA
Commodity
Established
Tolerance
(
ppm)
Reassessed
Tolerance
(
ppm)
Comments
[
Correct
Commodity
Definition]

bean,
mung,
seed
2.0
0.2
Bean,
mung,
seed
tomatoes
0.05
None
Revoke,
use
deleted
The
food
use
subject
to
this
TRED
is
listed
in
Table
2.
The
Agency
has
not
identified
any
label
amendments
which
should
be
implemented
as
a
result
of
this
TRED.
3
Table
2.
Food/
Feed
Use
Patterns
Subject
to
Tolerance
Reassessment
for
4­
CPA
Application
a)
Type
b)
Timing
c)
Equipment
Formulation
[
EPA
Reg.
No.]
Application
Rate
Use
Directions
and
Limitations
beans,
mung,
seed
a)
immersion
bath
b)
seedling
germination
c)
water
bath
Soluble
concentrate
96.2
%
ai
[
8906­
1]
7.4
X
10­
4
lb
ai
/
100
lbs
bean
seeds
Do
not
feed
treated
hulls
or
bean
parts
to
livestock.

This
letter
summarizes
the
Agency's
decision
on
the
tolerance
reassessment
for
4­
CPA.
Please
contact
Mark
Howard
of
my
staff
with
any
questions
regarding
this
decision.
He
may
be
reached
by
phone
at
(
703)
308­
8172
or
by
e­
mail
at
howard.
markt@
epa.
gov.

Sincerely,

Lois
A.
Rossi,
Director
Special
Review
and
Reregistration
Division
Enclosure:
Human
Health
Risk
Assessment
for
the
4­
CPA
TRED
4
Attachment
One
Technical
Support
Documents
for
the
4­
CPA
TRED
1.
Anderson,
Dave
(
USEPA/
OPPTS/
OPP/
HED)
Toxicity
Studies
with
4­
Chlorophenoxyacetic
acid
(
4­
CPA)
and
Structures
Related
to
4­
CPA.
September
10,
2002.

2.
Christensen,
Carol
(
USEPA/
OPPTS/
OPP/
HED)
4­
Chlorophenoxyacetic
acid.
HED
Human
Health
Risk
Assessment
for
the
Tolerance
Reassessment
Eligibility
Document
(
TRED).
March
12,
2003.

3.
Corbin,
Mark
(
USEPA/
OPPTS/
OPP/
EFED)
4­
Chlorophenoxyacetic
acid
TRED.
Estimated
Drinking
Water
Concentrations
for
4­
CPA
for
use
in
the
Human
Health
Risk
Assessment.
September
11,
2002.

4.
Corbin,
Mark
(
USEPA/
OPPTS/
OPP/
EFED)
4­
CPA
B
Evaluation
of
Endangered
Species
for
the
Tolerance
Reassessment
Decision
(
TRED)
Document
for
4­
CPA.
Addendum
to
the
September
11,
2002
EFED
Drinking
Water
Concentrations.
March
24,
2003
