    
1
  
2
UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON,
D.
C.
20460
OFFICE
OF
PREVENTION,
PESTICIDES
AND
TOXIC
SUBSTANCES
Chemical:
MCPB,
MCPB
Sodium
PC
Code:
019202,
019201
DP
Barcodes:
319759
MEMORANDUM
DATE:
07
March
2006
SUBJECT:
Comment
Phase
III
for
Reregistration
of
MCPB
and
MCPB
Sodium
FROM:
Marie
Janson,
Environmental
Scientist
Ed
Odenkirken,
Senior
Scientist
Amer
Al­
Mudallal,
Chemist
Nadar
Elkassabany,
Acting
Branch
Chief
Environmental
Risk
Branch
1
Environmental
Fate
and
Effects
Division
(
7507C)

TO:
Susan
Lewis,
Branch
Chief
Demson
Fuller,
CRM
James
Parker,
CRM
Registration
Branch
1
SRRD
Division
(
7505C)

Attached
please
find
the
Environmental
Fate
and
Effects
Division's
(
EFED)
revised
comments
environmental
risk
assessment
for
the
proposed
registration
of
MCPB
as
an
herbicide
on
peas.
Supported
formulations
of
MCPB
are
Thistrol
®
Herbicide
(
71368­
5)
and
Sodium
MCPB
Solution
(
71368­
7).

The
additional
comments
from
EFED
on
the
draft
risk
assessment
on
science
or
interpretation
are
addressed
in
this
Phase
III,
additional
comments
from
EFED
3/
07/
06.
    
2
  
2
Environmental
Fate
and
Ecological
risk
assessment
Potential
risks
to
non­
target
organisms
Page
2
paragraph
3
EFED
made
changes
to
Potential
chronic
risks
to
birds
and
aquatic
organisms
to
Potential
chronic
risks
to
aquatic
organisms.

1.
Non
Target
Risks
to
animals
and
Plants
Page
40
paragraph
1
The
sentence
chronic
risk
to
freshwater
fish
and
invertebrates
can
not
be
assessed
because
chronic
toxicity
data
have
not
been
submitted.
EFED
made
changes
to
the
above
sentence
that
added
estuarine
marine
fish
and
invertebrates
data
also
was
not
submitted.

Page
40
paragraph
12
EFED
deleted
the
following
sentence:
However,
the
LOCs
for
endangered
freshwater
vascular
plants
were
exceeded
for
the
ground
and
aerial
spray
application
scenarios.
This
sentence
was
replaced
with
Endangered
freshwater
vascular
plants
can
not
be
assessed
due
to
a
non­
discreet
NOEC
value.

Appendix
F
Data
Requirements
Page108
Table
of
Ecological
Toxicity
Data
Requirements
for
72­
4b
Freshwater
invertebrate
life
cycle
daphnia
EFED
changed
from
reserved
to
Yes
need
more
data.
EFED
added
72­
4b
Estuarine
marine
invertebrate
life
cycle
daphnia
in
reserve.
The
above
changes
were
also
made
on
data
requirement
table
pages
8­
9.
