MEMORANDUM
Subject:
Asulam
(
List
A,
Case
0265,
Chemical
106901/
02).
Tolerance
Reassessment
Eligibility
Decision
Document.
Product
and
Residue
Chemistry
Chapter.
DP
Barcode
D278884.

From:
José
J.
Morales,
Chemist
Reregistration
Branch
III
Health
Effects
Division
(
7509C)

Through:
Catherine
Eiden,
Branch
Senior
Scientist
Reregistration
Branch
III
Health
Effects
Division
(
7509C)

To:
Demson
Fuller,
Chemical
Review
Manager
Reregistration
Branch
I
Special
Review
and
Reregistration
Division
(
7508W)

SRRD
has
requested
that
HED
conduct
a
Tolerance
Reassessment
Eligibility
Decision
Document
for
asulam.
The
Asulam
Reregistration
Standard
Guidance
Document
was
issued
12/
87
and
was
based
on
the
Asulam
Reregistration
Standard
Science
Chapter
dated
8/
28/
87.
The
Asulam
Product
and
Residue
Reregistration
Standard
Update
was
completed
1/
15/
91.
The
Product
Chemistry
Chapter
and
the
Residue
Chemistry
Chapter
for
the
Asulam
Reregistration
Eligibility
Document
(
RED)
were
completed
on
04/
16/
94
(
DP
Barcodes
D193175
and
D198030;
CBRS
Nos.
12299
and
13041).
A
revision
to
the
chronic
anticipated
residues
(
Table
C)
was
subsequently
made
(
S.
Funk,
DP
Barcode
D208551,
CBRS
No.
14623,
12/
06/
94).
The
Metabolism
Committee
met
on
12/
13/
94
and
decided
that
the
metabolite
quinone/
hydroquinone
need
not
be
considered
further
in
risk
assessments
(
S.
Funk,
01/
18/
95
Memorandum
of
Committee
Meeting).
The
Residue
Chemistry
Chapter
was
revised
(
1/
24/
95,
D198030,
S.
Funk)
to
incorporate
the
deletion
of
quinone/
hydroquinone
from
the
residue
of
concern,
the
revised
anticipated
residues,
and
the
review
of
a
registrant
submission
on
storage
stability
received
after
the
original
Chapter
date
(
04/
94).

A
tolerance
is
established
for
negligible
residues
of
asulam
per
se
in/
on
sugarcane
at
0.1
ppm
[
40
CFR
§
180.360].
HED
has
recommended
that
the
tolerance
expression
be
revised
to
include
all
metabolites
containing
the
sulfanilamide
moiety.
An
adequate
enforcement
method
is
available
for
the
determination
of
combined
residues
of
asulam
and
all
metabolites
containing
the
sulfanilamide
moiety
in/
on
sugarcane.
Conclusion
All
residue
chemistry
deficiencies
noted
in
the
1/
24/
95
Residue
Chemistry
Chapter
of
the
Asulam
RED
have
been
adequately
addressed.
Sufficient
data
are
now
available
to
reassess
all
tolerances
associated
with
asulam
use
listed
in
40
CFR
§
180.360.
Some
product
chemistry
deficiencies
remain
outstanding,
but
they
do
not
impact
the
tolerance
reassessment
decision.

Background
Asulam
(
methyl­
4­
sulfanilylcarbamate)
is
a
postemergent
systemic
carbamate
herbicide
marketed
under
the
trade
name
ASULOX
®
Herbicide
by
Aventis
CropScience.
ASULOX
®
contains
the
sodium
salt
of
asulam
and
is
registered
for
use
on
sugarcane
as
a
3.34
lb/
gal
soluble
concentrate/
liquid
(
SC/
L)
formulation.
This
formulation
may
be
applied
postemergence
as
a
band
or
broadcast
application
using
ground
or
aerial
equipment
or
as
a
spot
treatment.
Apart
from
ITS
food
use
on
sugarcane,
asulam
is
used
on
christmas
tree
plantations,
ornamentals,
turf
(
sod
farms
only)
and
non­
cropland
uses.

Asulam
is
primarily
used
in
agriculture
with
key
markets
in
Florida
and
Louisiana.
Sugarcane
is
the
major
use
site
for
asulam
(
95%
of
the
market).
The
asulam
use
rate,
for
sugarcane,
ranges
from
2.5
to
3.34
lbs
a.
i./
A
and
can
applied
up
to
two
times
per
year.
For
all
other
uses,
it
can
be
applied
only
once.
The
average
rate
of
2.5
lbs
ai/
acre
is
the
typical
labeled
use
rate
for
Sugarcane.

Apart
from
its
use
on
sugarcane,
asulam
is
used
on
Christmas
tree
plantations,
ornamentals,
turf
(
Sod
Farms
Only)
and
non­
cropland
uses
(
boundary
fences,
fencerows,
hedgerows,
lumberyards,
storage
areas
and
industrial
plant
sites,
and
warehouse
lots).
For
Christmas
trees
and
ornamentals,
the
label
use
rate
is
3.34
lbs
a.
i./
A
and
can
be
applied
once
per
year
as
a
postemergent
treatment.
For
turf,
the
label
use
rate
is
about
2
lbs.
a.
i./
A
and
can
be
applied
once
per
year.
For
non­
cropland
uses,
the
label
use
rate
ranges
between
2.9
lbs
a.
i./
A
to
3.34
lbs
a.
i./
A
and
can
be
applied
once
per
year.

Detailed
Considerations
The
following
deficiencies
were
noted
in
the
1/
24/
95
HED
Residue
Chemistry
Chapter:

GLN
860.1200:
Directions
for
Use
The
registrant
must
submit
label
amendment
requests
for
the
use
of
asulam
on
sugarcane.
The
amendments
must
include
lower
maximum
application
rates
and/
or
longer
PHIs,
must
be
region
specific,
and
must
be
supported
by
new
field
trials.

2
GLN
860.1300:
Nature
of
the
Residue
­
Plants
The
HED
Metabolism
Committee
has
determined
that
the
presence
or
absence
of
radiolabeled
quinone
and/
or
hydroquinone
must
be
determined
by
a
new
sugarcane
metabolism
study.
It
was
also
concluded
that
determination
of
asulam,
free
and
conjugated,
sulfanilamide,
N4
­
acetylasulam,
and
N4
­
acetylsulfanilamide
as
a
common
moiety
is
acceptable.

GLN
860.1500:
Crop
Field
Trials
New
field
trials
are
required
for
sugarcane
using
modified
PHIs
and
application
rates;
current
data
show
an
overtolerance
situation
for
the
combined
residue
of
asulam
and
its
sulfanilamide­
containing
metabolites.

GLN
860.1850:
Confined
Accumulation
in
Rotational
Crops
A
confined
rotational
crop
study
is
required.
A
preliminary
report
was
submitted
(
MRID
41857701),
but
contained
no
details
on
the
isolation
and
characterization/
identification
of
the
radiolabeled
residues.
A
plantback
interval
of
at
least
6
months
is
required.

These
deficiencies
have
been
addressed
in
the
following
reviews:

The
HED
Metabolism
Committee
Meeting
Held
on
December
13,
1994:
Quinone/
Hydroquinone
Metabolite
of
Asulam
(
S.
Funk,
1/
24/
95,
DP
Barcode
none).

Asulam
(
List
A,
Case
0265,
Chemical
106901/
02).
Sugarcane
Field
Trials
(
S.
Funk,
DP
Barcode
D219787,
2/
23/
96).

Asulam
(
List
A,
Case
0265,
Chemical
106901/
02).
RPAC
Response
to
the
Reregistration
Eligibility
Decision
Document.
MRID
43902500
(
Product
Chemistry).
MRID
43902501
(
Confined
Rotational
Crop).
S.
Funk,
DP
Barcode
D223175,
5/
14/
96.

The
following
deficiencies
remain
outstanding:

1.
The
registrant
proposes
a
tolerance
for
asulam
residue
in/
on
cane
of
0.5
ppm,
resulting
from
2
applications,
each
3.34
lbs.
a.
i./
Acre,
with
a
100
day
PHI.
The
data
do
not
support
this
tolerance.
For
the
proposed
use
pattern,
the
maximum
residue,
corrected
for
loss
in
storage,
is
0.71
ppm.
A
tolerance
of
1.0
ppm
is
appropriate
for
residues
of
asulam
and
the
sulfanilamide­
containing
metabolites
in/
on
sugarcane.
This
replaces
the
original
tolerance
of
0.1
ppm
or
the
reevaluated
tolerance
of
15
ppm
from
the
Reregistration
Eligibility
Decision
Document
(
S.
Funk,
1/
24/
95,
D198030).

2.
HED
recommends
that
the
registrant
request
label
amendments
specifying
a
maximum
of
two
asulam
applications
per
year
to
sugarcane
at
a
maximum
single
application
rate
of
3
3.34
lbs.
a.
i./
A,
a
PHI
of
100
days
for
Louisiana,
a
PHI
of
140
days
for
the
remainder
of
the
US
mainland,
and
a
PHI
of
400
days
for
Hawaii.
If
the
registrant
requests
the
suggested
label
changes,
no
further
sugarcane
field
trial
data
are
required
for
asulam
at
this
time.
No
plantback
restrictions
are
required
on
the
label.

3.
Based
on
the
highest
average
field
trial
residue
and
the
concentration
factor
from
processing,
a
tolerance
of
30
ppm
is
needed
for
asulam
and
sulfanilamide­
containing
metabolite
residues
in
molasses.

4.
The
decrease
in
the
sugarcane
tolerance
for
asulam
and
its
sulfanilamide
containing
metabolites
from
the
reevaluated
15
ppm
to
1
ppm
does
not
alter
the
previous
conclusion
that
residues
of
asulam
and
the
sulfanilamide­
containing
metabolites
are
anticipated
in
ruminant
commodities
from
a
diet
containing
10%
molasses.
Animal
commodity
tolerances
should
be
proposed,
0.05
ppm
for
ruminant
milk
and
meat
and
fat
and
0.2
ppm
for
ruminant
meat
byproducts.
There
are
no
significant
poultry
feed
items;
poultry
commodity
tolerances
are
not
needed.

5.
Due
to
the
small
incremental
upper
bound
risk
from
hydroquinone/
quinone
on
sugarcane
from
the
use
of
asulam
when
compared
to
natural
background
levels
of
quinone/
hydroquinone
on
other
commodities,
no
further
risk
assessment
will
be
required
for
the
asulam
metabolite
hydroquinone/
quinone.

6.
Because
hydroquinone/
quinone
remains
a
chemical
of
toxicological
concern,
if
the
registrant
proposes
new
uses
for
this
chemical,
new
plant
metabolism
studies
must
be
performed
(
relevant
to
the
proposed
new
uses),
aimed
specifically
at
determining
the
presence
and
concentration
of
radiolabeled
hydroquinone/
quinone.
The
registrant
should
also
determine
the
naturally
occurring
background
levels
of
hydroquinone/
quinone
and
arbutin
in
sugarcane.
The
Metabolism
Committee
will
reconsider
its
position
if
new
metabolism
studies
show
that
quinone/
hydroquinone/
arbutin
comprises
a
significant
portion
of
the
radiolabeled
residue.

7.
The
following
product
chemistry
data
guidelines
remain
unfulfilled
for
the
technical
asulam
sodium
salt:
GLN
830.6317
(
Storage
Stability)
and
830.6320
(
Corrosion
Characteristics).

The
tolerance
reassessment
is
shown
in
Table
1.

4
Commodity
Table
1.
Tolerance
Reassessment
Summary
Current
Tolerance
(
ppm)
Tolerance
Reassessment
(
ppm)
Comment
Tolerance
listed
under
40
CFR
§
180.360
Sugarcane
0.1
1.0
Tolerances
to
be
Established
Under
40
CFR
§
180.360
Molasses
 
30
Milk
 
0.05
Meat
and
Fat
of
Cattle,
Goat,
Hogs,
Horses,
Sheep
 
0.05
Meat
byproducts
of
Cattle,
Goat,
Hogs,
Horses,
Sheep
 
0.2
Attachments:

Asulam
(
List
A,
Case
0265,
Chemical
106901/
02).
Update
to
Residue
Chemistry
Chapter
for
the
Reregistration
Eligibility
Decision
Document
(
S.
Funk,
1/
24/
95,
DP
Barcode
D198030).

The
HED
Metabolism
Committee
Meeting
Held
on
December
13,
1994:
Quinone/
Hydroquinone
Metabolite
of
Asulam
(
S.
Funk,
1/
24/
95,
DP
Barcode
none).

Asulam
(
List
A,
Case
0265,
Chemical
106901/
02).
Sugarcane
Field
Trials
(
S.
Funk,
DP
Barcode
D219787,
2/
23/
96).

Asulam
(
List
A,
Case
0265,
Chemical
106901/
02).
RPAC
Response
to
the
Reregistration
Eligibility
Decision
Document.
MRID
43902500
(
Product
Chemistry).
MRID
43902501
(
Confined
Rotational
Crop).
S.
Funk,
DP
Barcode
D223175,
5/
14/
96.

5
