Page
1
of
5
Addendum
to
Dicofol
RED
Purpose
of
Addendum
The
United
States
Environmental
Protection
Agency
(
hereafter
referred
to
as
EPA
or
Agency)
is
issuing
this
document
as
an
addendum
to
the
1998
Reregistration
Eligibility
Decision
(
RED)
for
dicofol
and
as
a
revision
to
the
Occupational
Exposure
Assessment,
dated
November
19,
1999.
At
the
time
the
RED
was
signed,
the
Agency
was
concerned
with
occupational
exposure
and
risk.
At
that
time,
most
short­
term
and
all
intermediate­
term
exposure
scenarios
for
mixers,
loaders,
applicators,
and
field
workers
were
of
concern
to
the
Agency,
even
when
using
personal
protective
equipment
and
engineering
controls.
However,
the
Agency
believed
that
the
default
assumptions
that
were
used
to
arrive
at
these
conclusions
led
to
an
overestimate
of
risk
(
e.
g.;
the
default
assumption
of
100%
dermal
absorption).
To
improve
the
estimation
of
risk,
the
registrant
agreed
to
submit
a
dermal
toxicity
study
and
a
dislodgeable
foliar
residue
study.
This
information
was
submitted
to
the
Agency,
and
a
revised
occupational
risk
assessment
was
conducted.
After
completing
the
revised
risk
assessment,
post­
application
occupational
exposure
was
still
a
concern
for
most
crops.
Recently,
all
dicofol
occupational
use
scenarios
have
been
re­
evaluated
and
the
Agency
is
issuing
this
document
to
address
concerns
that
were
initially
highlighted
in
the
RED.

Dicofol
Overview
Dicofol
is
an
organochlorine
miticide
which
is
registered
for
use
on
beans
(
dry,
lima,
and
green),
cotton,
hops,
mint,
peppers,
tomatoes,
citrus,
pecans,
walnuts,
tree
nuts,
cucurbits,
grapes,
pomefruit,
stone
fruit,
strawberries,
melons,
and
non­
residential
lawns
and
ornamentals.
Special
Local
Need
registrations
are
currently
active
for
use
on
alfalfa
and
cane
berries.
At
the
time
the
RED
was
signed,
dicofol
was
an
important
component
of
mite
control
programs.
Today
there
are
many
alternatives
to
dicofol
that
are
equally
efficacious
and
cost
effective,
resulting
in
an
overall
decrease
in
dicofol
use.

According
to
EPA
resources,
usage
on
three
major
use
sites
(
cotton,
grapefruit,
and
oranges)
has
significantly
declined
since
1998.
For
example,
publicly
available
U.
S.
Department
of
Agriculture
National
Agricultural
Statistic
Service
(
NASS)
data
show
a
75%
decrease
in
dicofol
use
on
cotton
(
approximately
400,000
pounds
active
ingredient
in
1998
and
approximately
100,000
pounds
active
ingredient
in
2003).
The
1998
RED
cites
that
dicofol
was
used
on
approximately
22%
of
grapefruit
grown
in
the
U.
S.
(
estimated
maximum)
at
that
time.
Currently,
the
Agency's
resources
show
that
on
a
national
scale,
approximately
7%
of
grapefruit
is
treated
with
dicofol
and
annual
pounds
of
active
ingredient
applied
have
decreased
94%
since
1995.
Additionally,
the
1998
RED
cites
that
dicofol
was
used
on
approximately
13%
of
oranges
grown
in
the
U.
S.
(
estimated
maximum)
at
that
time.
Currently,
the
Agency's
resources
show
that
less
than
5%
of
oranges
grown
in
the
U.
S.
are
treated
with
dicofol
and
annual
pounds
of
active
ingredient
applied
have
decreased
97%
since
1995.
Page
2
of
5
Registered
end­
use
products
are
formulated
as
emulsifiable
concentrates
or
wettable
powders.
These
formulations
may
be
applied
as
concentrates
or
dilute
sprays
using
aircraft
or
ground
spray
equipment.
Three
of
the
twelve
currently
registered
products
were
registered
after
the
RED
was
signed,
but
these
must
also
be
modified
to
follow
the
mitigation
set
forth
in
the
RED
and
Addendum
to
the
RED.
In
addition,
compliance
with
this
mitigation
is
also
required
for
three
Special
Local
Need
(
SLN)
products.

Work
the
Agency
has
Done
Since
the
Completion
of
the
RED
Since
the
issuance
of
the
RED,
the
Agency
received
and
evaluated
a
90­
day
dog
dermal
study
(
MRID
44720501)
and
a
chemical
specific
dislodgeable
foliar
residue
study
(
MRID
45290602).
The
review
of
the
90­
day
dermal
study
resulted
in
the
revision
of
selected
endpoints.
Changes
and
discussion
of
changes
are
presented
in
the
Revised
Report
of
the
Hazard
Identification
Assessment
Review
Committee,
dated
September
9,
1999.
The
Agency
used
the
newly
submitted
information
and
re­
evaluated
postapplication
occupational
exposures.
Most
post­
application
exposure
scenarios
continued
to
be
of
concern
to
the
Agency.

The
Agency
has
concluded
that
revised,
longer
REIs
are
needed.
For
crops
on
which
dicofol
is
used,
workers
may
be
required
to
work
in
fields
for
extended
periods
of
time.
The
Agency
is
concerned
that
certain
activities,
including
hand
harvesting
and
moving
from
one
treated
field
to
the
next,
will
potentially
put
workers
at
risk.
Crops
in
this
category
include
citrus
(
grapefruit,
oranges,
nectarines,
and
tangelos),
stone
fruits
(
apricots,
nectarines,
and
peaches),
tree
nuts,
mint,
tomatoes,
peppers,
cucurbits,
pomefruit
(
apples
and
pears),
grapes,
beans,
strawberries,
cane
berries,
and
nonresidential
lawns
and
ornamentals.
However,
the
Agency
believes
increasing
REIs
for
these
crops
will
not
likely
impact
production
of
these
crops
because
adequate
alternatives
are
available
and
dicofol
applications
can
be
made
when
field
activities
are
not
required.

In
order
to
determine
the
economic
and
biological
impact
of
imposing
longer
REIs,
EPA's
Office
of
Pesticide's
Biological
and
Economic
Analysis
Division
(
BEAD)
provided
benefit
assessments
for
selected
crops.
BEAD
examined
crops/
crop
groups
that
have
5%
or
more
percent
crop
treated
with
dicofol,
on
a
national
basis.
The
crops
that
were
included
in
the
assessment
are:
citrus
(
grapefruit,
oranges,
and
tangelos),
stone
fruits
(
apricots,
nectarines,
and
peaches),
and
tree
nuts
(
pecans).
The
complete
results
of
the
benefits
assessments
are
provided
with
this
addendum
as
supporting
documents.

At
present,
all
dicofol
labels
require
REIs
of
12
hours.
However,
the
Agency
believes
that
typical
field
activities
will
require
workers
to
work
in
fields
for
extended
periods
of
time
and
thus
result
in
exposures
exceeding
levels
of
conern
when
an
REI
of
12
hours
is
observed.
Therefore,
the
Agency
is
increasing
REIs
for
most
crops
in
order
to
protect
post­
application
occupational
workers.
For
cotton
and
alfalfa,
which
are
largely
mechanically
harvested,
the
Agency
believes
that
post­
application
exposures
will
be
Page
3
of
5
minimal,
eliminating
a
major
source
of
potential
exposure.
Therefore,
the
Agency
has
concluded
that
the
re­
entry
intervals
of
12
hours
can
remain
the
same
for
cotton
and
alfalfa.

Revised
Re­
entry
Intervals
The
Agency
has
determined
that
dicofol
labels
need
to
be
revised
to
incorporate
longer
REIs
for
the
following
crops:
citrus,
pecans,
walnuts,
stone
fruit,
cucurbits,
pomefruit,
beans,
grapes,
non­
residential
turf
and
ornamentals,
tomatoes,
peppers,
strawberries,
cane
berries,
mint,
and
hops.
The
Agency
believes
that
there
is
the
potential
that
post­
application
field
activities
will
expose
occupational
workers
for
an
extended
period
of
time
to
dicofol,
a
period
of
time
that
could
result
in
adverse
health
effects.
To
determine
the
biological
and
economical
impact
of
increasing
REIs
for
crops
that
have
more
than
5%
crop
treated
nationally,
the
Agency
conducted
benefits
assessments.
As
discussed
previously,
these
crops
include
citrus,
pecans,
and
stone
fruit.
The
Agency
has
received
information
from
USDA
to
help
inform
this
decision.
A
brief
summary
of
rationale
used
by
the
Agency
for
these
crops
is
included
below
and
complete
assessments
are
included
as
supporting
information.

To
protect
workers,
the
Agency
will
require
that
new
labels
include
the
following
REIs
for
the
specified
crops:

 
Citrus
(
oranges,
tangelos,
tangerines,
grapefruit)
­
87
days
 
Stone
fruit
(
apricots,
peaches,
nectarines)
­
33
days
 
Pecans/
Walnuts/
Tree
Nuts
­
49
days
(
applications
must
be
made
before
shuck
split)
 
Cucurbits
­
21
days
 
Pomefruit
(
apples,
pears)
­
35
days
 
Beans
­
33
days
 
Grapes
­
39
days
 
Sod/
Turf
(
surrogate
for
non­
residential
turf)
­
29
days
 
Tomatoes/
Peppers
­
25
days
 
Strawberries
(
and
Cane
Berries)­
31
days
 
Mint
­
32
days
 
Hops
­
29
days
Citrus
Dicofol
is
applied
to
citrus
to
control
a
complex
of
mites
including
spider
mites
and
rust
mites.
Currently,
dicofol
is
not
significantly
used
on
oranges,
tangelos,
or
tangerines.
In
Texas
approximately
25%
of
grapefruit
are
treated
with
dicofol.

Dicofol
labels
currently
specify
a
12
hour
REI
for
citrus.
The
Agency
is
concerned
that
an
REI
of
12
hours
is
not
restrictive
enough,
and
that
residue
levels
of
dicofol
may
be
present
that
could
potentially
harm
workers
who
are
participating
in
field
activities.
Therefore,
a
new
REI
of
87
days
will
be
established
for
citrus.
Page
4
of
5
The
Agency
believes
that
there
will
not
likely
be
a
negative
impact
on
grapefruit
production
in
Texas
if
REIs
are
extended,
as
dicofol
will
be
shifted
in
the
rotational
spray
program
to
a
period
where
field
activities
will
not
be
restricted.
In
addition,
even
with
a
longer
REI,
dicofol
application
would
still
be
an
option
during
the
non­
harvest
period
(
June­
September).
Further,
numerous
alternative
miticides
are
available
which
are
both
efficacious
and
cost
effective.
Alternatives
include,
but
are
not
limited
to:
abamectin,
formetanate
hydrochloride,
diflubenzuron,
pyridaben,
propargite,
and
fenbutatin
oxide.
These
alternatives
have
REIs
that
range
from
12
to
48
hours.
A
more
complete
list
of
alternative
miticides,
as
well
as
a
discussion
of
alternatives,
is
included
in
the
"
Benefits
Assessment
for
Dicofol
on
Citrus:
Oranges,
Grapefruit,
Tangerines,
and
Tangelos",
dated
April
13,
2005.

Stone
Fruit
Dicofol
is
applied
to
stone
fruits
to
control
several
types
of
mites,
including
webspinning
mites.
Over
the
past
four
years,
national
use
of
dicofol
on
stone
fruit
has
declined.

Dicofol
labels
currently
specify
a
12
hour
REI
for
stone
fruit.
The
Agency
is
concerned
that
a
12
hour
REI
is
not
restrictive
enough
to
protect
field
workers
from
postapplication
exposures
to
dicofol.
Therefore,
a
new
REI
of
33
days
will
be
established
for
stone
fruit.

While
the
extended
REI
might
impact
timing
of
applications,
other
miticides
are
available
which
are
as
efficacious
and
economical
as
dicofol
for
mite
control.
Since
the
alternative
miticides
are
currently
used
to
treat
more
acres
annually
than
dicofol,
there
is
not
likely
to
be
either
a
biological
pest
control
impact
or
economic
impact
on
producers.
Alternatives
include,
but
are
not
limited
to:
abamectin,
bifenazate,
esfenvalerate,
fenbutotin
oxide,
and
insecticidal
oils.
A
more
complete
list,
as
well
as
a
discussion
of
alternatives,
is
included
in
the
"
Benefits
Assessment
for
Dicofol
on
Apricots,
Peaches,
and
Nectarines",
dated
March
23,
2005.
In
addition,
dicofol
can
still
be
used
but
producers
will
need
to
schedule
field
activities
around
new
REIs.

Pecans
(
Tree
Nuts)
Dicofol
is
applied
to
pecans
to
control
mites,
primarily
the
leaf
scorch
mite.
Dicofol
use
on
pecans
is
highest
in
Georgia
and
Louisiana,
where
approximately
34%
and
21%
of
pecans
are
treated,
respectively.

Dicofol
labels
currently
specify
a
12
hour
REI
for
pecans.
The
Agency
is
concerned
that
a
short
REI
would
allow
workers
to
re­
enter
treated
fields
when
residue
levels
are
of
concern
and
field
activities
could
result
in
extended
periods
of
exposure.
Therefore,
a
new
REI
of
49
days
will
be
established
for
tree
nuts.

Due
to
the
application
schedule
for
dicofol
(
July
through
October)
and
that
minimal
field
activities
that
require
contact
with
treated
foliage
take
place
during
this
Page
5
of
5
time,
extending
REIs
will
not
likely
impact
pecan
production.
To
further
ensure
that
workers
do
not
come
in
contact
with
treated
foliage
and
nuts
for
long
periods
of
time,
labels
need
to
specify
that
dicofol
can
only
be
applied
before
pecan
shuck
split
and
need
to
be
harvested
mechanically.

Attachments:

1.
Addendum
to
the
Dicofol
RED,
dated
September
8,
2005
2.
Dicofol­
Revised
Report
of
the
Hazard
Identification
Assessment
Review
Committee,
dated
September
8,
1999.

3.
Dicofol.
Revised
Refined
Post­
Application
Exposure
Estimates
(
Citrus,
Stonefruit,
Tree­
nut
crops),
dated
July
29,
2004.

4.
Dicofol:
Revised
Refined
Post­
Application
Exposure
Estimates
(
Apples,
Pears,
Beans,
Cotton,
Cucurbits,
Grapes,
Sod/
Turf),
dated
August
29,
2005.

5.
Dicofol:
Crop­
Specific
Refined
Post­
Application
Exposure
Estimates:
Pecans,
dated
December
9,
2004.

6.
Dicofol.
Revised
Refined
Post­
Application
Exposure
Estimates
for
Hops,
Mint
&
Strawberries,
dated
August
29,
2005.

7.
BEAD
Dicofol
Crop
Usage,
dated
June
25,
2004.

8.
Benefits
Assessment
for
Dicofol
on
Citrus:
Oranges,
Grapefruit,
Tangerines,
and
Tangelos,
dated
April
13,
2005.

9.
Pecans
Benefits
Assessment
for
Dicofol,
dated
March
23,
2005.

10.
Benefits
Assessment
for
Dicofol
on
Apricots,
Peaches,
and
Nectarines,
dated
March
23,
2005.

11.
Sow
AgroSciences
Response
to
Error­
Only
Comment
Period,
dated
August
17,
2005
