Minutes:
Dicrotophos
Meeting
­
AMVAC/
Bergeson
&
Campbell
Discussion
of
Proposed
Changes
to
the
IRED
Wednesday,
October
20,
2004
3pm,
Room
650
Attendees:
Ian
Chart,
AMVAC
Corporation
Ann
Manley,
AMVAC
Susan
Lewis,
EPA/
OPP/
SRRD
Laura
Parsons,
EPA/
OPP/
SRRD
Amaris
Johnson,
EPA/
OPP/
SRRD
Ray
Kent,
EPA/
OPP/
HED
Rebecca
Daiss,
EPA/
OPP/
HED
Robert
Perlis,
EPA/
OGC/
PBLO
Andrew
Simons,
EPA/
OGC/
PBLO
Judith
MacGregor,
Toxicology
Consulting
Services
Lisa
Campbell,
Bergeson
&
Campbell
Susan
Hunter­
Youngren,
Bergeson
&
Campbell
Summary:

At
AMVAC
Corporation's
request,
OPP
scientists
and
risk
managers
met
with
representatives
from
AMVAC,
and
Bergeson
&
Campbell
to
discuss
AMVAC's
data
submission
of
June
2004,
which
outlined
proposed
changes
to
the
toxicity
endpoints
in
the
Dicrotophos
IRED.
OPP
agreed
to
the
margin
of
exposure
(
MOE)
of
100
suggested
by
AMVAC
instead
of
the
previous
value
of
300,
due
to
the
submission
of
a
study
providing
a
NOAEL.
The
dermal
NOAEL
was
acceptable
at
2
mg/
kg/
day,
and
the
inhalation
NOAEL
0.1mg/
kg/
day.
Similarly,
AMVAC
provided
OPP
with
a
compelling
argument
for
short­
term
exposure
scenarios
instead
of
intermediate.
However,
AMVAC's
request
for
300
acres
as
representative
of
average
exposure
was
denied.
The
1200
acre
a
day
model
was
maintained
due
to
survey
findings
of
applicators
who
covered
this
acreage
in
a
day.
AMVAC
requested
the
review
of
their
dicrotophos­
specific
study
(
which
is
in
PHED)
in
lieu
of
the
entire
PHED
exposure
data
set.
OPP
disagreed
with
this
potential
change
in
protocol
and
has
continued
referencing
the
entire
database
because
it
provided
high
statistical
confidence,
linked
exposure
to
the
application
method,
and
placed
less
significance
on
the
chemical.
The
Agency
is
not
able
to
remove
the
10x
safety
factor
based
on
the
AMVAC
in
vitro
study.

AMVAC
broached
the
topic
of
maintaining
the
high
rate
of
0.5
lbs.
ai/
A
for
aerial
application,
through
limiting
the
number
of
acres
treated
ie.
300
acres
per
day.
It
was
suggested
that
this
acreage
restriction
could
be
monitored
similar
to
what
has
been
done
in
California.
In
California,
pilots
kept
ledgers
of
the
number
of
acres
they
treated
each
day.
OPP
responded
that
past
attempts
at
acreage
restrictions
have
failed
because
they
were
extremely
hard
to
enforce.
Furthermore,
OPP
would
need
a
proposal
from
AMVAC
outlining
the
practicability
of
this
mitigation.
Bergeson
&
Campbell
inquired
further
about
the
chemicals
that
have
attempted
this
type
of
mitigation
and
the
reasons
that
OPP
has
denied
them.
OPP
referred
Bergeson
&
Campbell
to
OECA
to
discuss
the
enforcement
needs
and
issues
in
greater
detail.

OPP
told
AMVAC
that
they
would
consider
the
0.2
lbs
ai/
A
rate
for
aerial
application
because
the
new
risk
calculations
showed
no
adverse
risks
to
handlers
and
applicators
at
that
level.
AMVAC
had
requested
0.5lbs
ai/
A
for
late
season
flair­
ups
of
stink
bugs,
and
will
respond
to
OPP
with
their
decision
to
use
the
lower
0.2
lbs
ai/
A.
In
the
meantime,
AMVAC
will
draw
up
a
proposal
for
the
aerial
application
acreage
restriction
at
the
0.5lbs
ai/
A,
and
submit
draft
labels
to
OPP
by
the
required
November
22,
2004
deadline.
In
addition,
OPP
will
meet
with
AMVAC
again
(
around
December)
following
EFED's
review
of
the
"
quasi­
probabilistic"
study
submitted
by
AMVAC.
