UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON,
D.
C.
20460
OFFICE
OF
PREVENTION,
PESTICIDES
AND
TOXIC
SUBSTANCES
MEMORANDUM
Date:
03­
NOV­
2004
Subject:
Ametryn
RED
­
Reregistration
Eligibility
Decision.
Product
Chemistry
Considerations.
Case
No.
2010
DP
Barcode:
D307593
PC
Code:
080801
From:
William
H.
Donovan,
Ph.
D.,
Chemist
Reregistration
Branch
3
(
RRB3)
Health
Effects
Division
(
HED)
(
7509C)

Through:
Danette
Drew,
Branch
Senior
Scientist
RRB3/
HED
(
7509C)

To:
Mark
T.
Howard,
CRM
Reregistration
Branch
2
Special
Review
and
Registration
Division
(
7508C)

This
document
was
originally
prepared
under
contract
by
Dynamac
Corporation
(
20440
Century
Boulevard,
Suite
100;
Germantown,
MD
20874;
submitted
07/
26/
2004).
The
document
has
been
reviewed
by
the
HED
and
revised
to
reflect
current
OPP
policies.
Ametryn
RED:
Product
Chemistry
Considerations
Barcode:
D307593
2
Executive
Summary
Ametryn
[(
2­
ethylamino)­
4­(
isopropylamino)­
6­(
methylthio)­
s­
triazine]
is
a
selective
methylthiotriazine
herbicide
registered
for
the
control
of
broadleaf
and
grass
weeds
primarily
in
corn,
pineapple,
and
sugarcane.

Ametryn
is
a
FIFRA
List
B
reregistration
chemical.
Available
product
chemistry
data
were
assessed
in
the
Ametryn
Phase
4
Review
dated
11/
20/
90,
by
S.
Funk,
for
their
adequacy
in
fulfilling
data
requirements
for
reregistration
of
ametryn.
The
Phase
4
Review
required
additional
data
for
the
Ciba­
Geigy
(
now
Syngenta
Crop
Protection)
ametryn
technical
product
pertaining
to
starting
materials
and
enforcement
analytical
methods
(
830.1600
and
1800);
a
DCI
was
issued
10/
7/
91.
MRIDs
that
were
determined
to
be
acceptable
for
Phase
5
review,
as
well
as
data
submitted
subsequent
to
the
Phase
4
Review,
have
been
reviewed
by
the
Agency.

A
DCI
was
issued
9/
92
for
product
chemistry
data
on
hexachlorobenzene
(
HCB)
and
pentachlorobenzene
(
PCB)
in
technical
atrazine,
ametryn,
simazine,
prometryn,
prometon,
and
cyromazine
(
s­
triazine
pesticides
manufactured
via
a
common
trichloro­
s­
triazine
intermediate).
Ciba­
Geigy
submitted
a
data
waiver
request,
which
was
denied
(
MRID
42583102;
D186543,
2/
11/
93,
S.
Funk),
and
subsequently
proposed
to
analyze
atrazine
for
HCB/
PCB
and
to
use
the
results
to
determine
whether
analyses
of
the
other
s­
triazine
pesticides
were
needed.
The
Agency
agreed
that
if
the
atrazine
analysis
revealed
HCB
and/
or
PCB
above
the
LOQ
(
100
ppb),
then
analyses
would
be
required
for
the
other
s­
triazine
technical
products;
otherwise,
no
additional
PCB/
HCB
data
would
be
required
(
D189265,
4/
19/
93,
S.
Funk).
Based
on
the
analysis
results
for
atrazine,
analysis
of
the
ametryn
technical
product
for
HCB/
PCB
is
required
(
D195429,
10/
10/
95,
S.
Funk).

Additional
product
chemistry
data
are
required
for
the
Syngenta
90%
ametryn
T
(
EPA
Reg.
No.
100­
579).
Provided
that
the
registrant
submits
the
data
required
in
the
attached
data
summary
table
for
the
ametryn
T/
TGAI,
and
either
certifies
that
the
suppliers
of
beginning
materials
and
the
manufacturing
process
for
the
ametryn
T/
TGAI
have
not
changed
since
the
last
comprehensive
product
chemistry
review
or
submits
a
complete
updated
product
chemistry
data
package,
the
Agency
has
no
objections
to
the
reregistration
of
ametryn
with
respect
to
product
chemistry
data
requirements.

Product
Chemistry
Deficiencies
Additional
data
are
required
concerning
product
composition,
preliminary
analysis
(
analysis
for
HCB/
PCB),
certified
limits,
enforcement
analytical
method,
UV/
visible
absorption,
dissociation
constant,
and
solvent
solubility
(
OPPTS
830.1550,
1700,
1750,
1800,
7050,
7370,
and
xxxx)
for
the
Syngenta
90%
ametryn
T
(
EPA
Reg.
No.
100­
579).
Ametryn
RED:
Product
Chemistry
Considerations
Barcode:
D307593
3
N
N
N
N
H
S
C
H
3
NH
CH
3
CH
3
CH
3
Background
Identification
of
Active
Ingredient
The
PC
code
and
nomenclature
of
ametryn
are
listed
below
in
Table
1.
The
physicochemical
properties
of
ametryn
are
listed
in
Table
2.

TABLE
1.
Ametryn
Nomenclature
Chemical
structure
Common
name
Ametryn
Molecular
Formula
C9H17N5S
Molecular
Weight
227.35
IUPAC
name
N2­
ethyl­
N4­
isopropyl­
6­
methylthio­
1,3,5­
triazine­
2,4­
diamine
CAS
name
N­
ethyl­
N'­(
1­
methylethyl)­
6­(
methylthio)­
1,3,5­
triazine­
2,4­
diamine
CAS
#
834­
12­
8
TABLE
2.
Physicochemical
Properties
of
Ametryn
Parameter
Value
Reference
Melting
point
84.5­
86

C
MRID
40877301
pH
8­
9
at
20

C
(
1%
solution
in
water)
MRID
40877301
Density,
bulk
density,
or
specific
gravity
0.373
g/
mL
at
20

C
MRID
40877301
Water
solubility
0.020
g/
100
mL
at
20

C
MRID
40877301
Solvent
solubility
56.9
g/
100
mL
in
acetone
61.4
g/
100/
mL
in
methylene
chloride
51.6
g/
100
mL
in
methanol
46.0
g/
100
mL
in
toluene
24.2
g/
100
mL
in
n­
octanol
1.4
g/
100mL
in
n­
hexane
MRID
40877301
Vapor
pressure
2.74
x
10­
6
mm
Hg
at
25

C
MRID
40877301
Dissociation
constant,
pKa
4.02
at
20

C
MRID
40877301
Octanol/
water
partition
coefficient
KOW
=
423
(
log
P
=
2.63)
MRID
40877301
UV/
visible
absorption
spectrum
Not
available
Ametryn
RED:
Product
Chemistry
Considerations
Barcode:
D307593
4
Manufacturing­
use
Products
A
search
of
the
OPPIN
product
listing
conducted
5/
04
identified
a
single
technical
product
(
T)
registered
under
PC
Code
080801,
the
Syngenta
Crop
Protection,
Inc.
(
formerly
Ciba­
Geigy)
90%
T
(
EPA
Reg.
No.
100­
579).
Because
ametryn
is
a
List
B
chemical,
only
the
T/
TGAI
is
subject
to
a
reregistration
eligibility
decision.

830.1550­
7950
Product
Chemistry
Data
Requirements
The
current
status
of
the
product
chemistry
data
requirements
for
the
ametryn
T/
TGAI
is
presented
in
the
attached
data
summary
table.
Refer
to
this
table
for
a
listing
of
the
outstanding
product
chemistry
data
requirements.
Ametryn
RED:
Product
Chemistry
Considerations
Barcode:
D307593
5
Case
No.
2010
Chemical
No.
080801
Case
Name:
Ametryn
Registrant:
Syngenta
Crop
Protection,
Inc.
Product(
s):
90%
T
(
EPA
Reg.
No.
100­
579)

PRODUCT
CHEMISTRY
DATA
SUMMARY
Guideline
Number
Requirement
Are
Data
Requirements
Fulfilled?
1
MRID
Number
2
830.1550
Product
identity
and
composition
N
3,
4
40844701,
CSF
8/
19/
85
830.1600
Description
of
materials
used
to
produce
the
product
Y
40844701
830.1620
Description
of
production
process
Y
40844701
5,
43335901
6
830.1670
Discussion
of
formation
of
impurities
Y
40844701
830.1700
Preliminary
analysis
N
7
41067901
830.1750
Certified
limits
N
4,
8
40844701,
41067901,
CSF
8/
19/
85
830.1800
Enforcement
analytical
method
N
9
41067901
4
830.6302
Color
Y
40877301
830.6303
Physical
state
Y
40877301
830.6304
Odor
Y
40877301
830.6313
Stability
to
normal
and
elevated
temperatures,
metals,
and
metal
ions
Y
40877301,
42470901
10,
42631501
11
830.7000
pH
Y
40877301
830.7050
UV/
visible
absorption
N
830.7200
Melting
point/
melting
range
Y
40877301
830.7220
Boiling
point/
boiling
range
N/
A
12
830.7300
Density/
relative
density/
bulk
density
Y
40877301
830.7370
Dissociation
constant
N
13
40877301
830.7550
Partition
coefficient
(
n­
octanol/
water),
shake
flask
method
Y
40877301
830.7840
Water
solubility;
column
elution
method;
shake
flask
method
Y
40877301
830.
xxxx
Solvent
solubility
N
13
40877301
830.7950
Vapor
pressure
Y
40877301
1
Y
=
Yes;
N
=
No;
N/
A
=
Not
Applicable.

2
All
references
were
found
to
be
acceptable
for
Phase
5
review
in
the
Ametryn
Phase
4
Review
(
11/
20/
90)
unless
otherwise
noted.

3
Nominal
concentrations
must
be
proposed
for
the
active
and
inert
ingredients
and
for
all
related
compounds
(
i.
e.,
impurities)
present
in
the
product
at

0.1%.

4
An
updated
CSF
is
required
reflecting
the
following:
(
i)
the
current
registrant;
(
ii)
the
nominal
concentration
and
upper
and
lower
certified
limits
for
the
active
ingredient
and
each
inert
ingredient;
(
iii)
the
purpose
of
each
inert
ingredient
in
the
product;
and
(
iv)
the
nominal
concentration
and
upper
certified
limit
for
all
impurities
present
in
the
product
at

0.1%.

5
D169896,
4/
20/
93,
S.
Funk.
Ametryn
RED:
Product
Chemistry
Considerations
Barcode:
D307593
6
6
D207635,
currently
under
review.

7
Analysis
for
HCB/
PCB
remains
outstanding.
We
note
that
if
HCB
or
PCB
is
detected,
an
upper
certified
limit
will
need
to
be
proposed
and
included
on
the
CSF,
and
an
enforcement
method
will
be
required.

8
An
explanation
of
the
basis
of
the
certified
limits
proposed
in
the
Certification
of
Limits
included
in
MRID
41067901,
including
how
the
certified
limits
were
determined,
is
required;
otherwise,
revised
certified
limits
must
be
proposed.

9
The
method
for
the
active
ingredient
must
be
resubmitted
as
a
non­
confidential
method.

10
D182839,
10/
27/
92,
A.
Aikens.

11
D187515,
2/
25/
93,
F.
Toghrol.

12
Data
are
not
required
because
the
TGAI
is
a
solid
at
room
temperature.

13
The
method
used
and
raw
data
to
support
the
study
results
are
required.
Ametryn
RED:
Product
Chemistry
Considerations
Barcode:
D307593
7
BIBLIOGRAPHY
Study
Citations
40844701
Lail,
L.
(
1988)
Product
Chemistry:
Technical
Ametryn:
Study
No.
PC­
88­
018.
Unpublished
study
prepared
by
Ciba­
Geigy
Corp.
205
p.

40877301
Lail,
L.
(
1988)
Technical
Ametryn:
Product
Chemistry:
Study
No.
PC­
88­
018.
Unpublished
study
prepared
by
Ciba­
Geigy
Corp.
136
p.

41067901
Lail,
L.
(
1989)
Technical
Ametryn:
Product
Chemistry:
Study
No.
PC­
89­
002.
Unpublished
study
prepared
by
Ciba­
Geigy
Corp.
108
p.

42470901
Stubbs,
D.
(
1992)
Product
Chemistry:
Ametryn
Technical:
Lab
Project
Number:
PC­
92­
027.
Unpublished
study
prepared
by
CIBA­
GEIGY
Corp.
5
p.

42583102
Lail,
L.;
Verma,
M.
(
1992)
Product
Chemistry:
Technical
Ametryn:
Lab
Project
Number:
PC­
92­
039.
Unpublished
study
prepared
by
CIBA­
GEIGY
Corp.,
Agricultural
Division.
19
p.

42631501
Stubbs,
D.
(
1993)
Product
Chemistry
(
Stability):
Technical
Ametryn:
A
Supplement.
Unpublished
study
prepared
by
Ciba­
Geigy.
17
p.

43335901
McCain,
P.
(
1994)
Technical
Ametryn
Product
Chemistry
(
Manufacturing
Process):
Addendum:
Lab
Project
Number.
Unpublished
study
prepared
by
Ciba­
Geigy
Corp.
8
p.

Agency
Memoranda
Citations
DP
Barcode(
s):
D182839
Subject:
Ametryn
Reregistration.
Product
Chemistry
Guideline
63­
13
­
Stability.
Response
to
Phase
4
Review.
From:
A.
Aikens
To:
L.
Deluise/
T.
Luminello
Dated:
10/
27/
92
MRID(
s):
42470901
DP
Barcode(
s):
D186543
Subject:
Data
Call­
In
for
Hexachlorobenzene
and
Pentachlorobenzene
in
Technical
Ametryn;
Waiver
Request.
From:
S.
Funk
To:
D.
Utterback
Dated:
2/
11/
93
MRID(
s):
42583102
Ametryn
RED:
Product
Chemistry
Considerations
Barcode:
D307593
8
DP
Barcode(
s):
D187515
Subject:
Ametryn
Reregistration:
a
List
B
Chemical
(
Chemical
No.
080801;
Case
No.
2010).
CIBA­
GEIGY:
Response
to
the
Ametryn
Product
Chemistry
Phase
4
Review
(
dated
11/
19/
90)
data
requirements
Regarding
Stability
(
Guideline
#
63­
13).
From:
F.
Toghrol
To:
K.
Davis/
T.
Luminello
Dated:
2/
25/
93
MRID(
s):
42631501
DP
Barcode(
s):
D189265
Subject:
Data
Call­
In
for
Hexachlorobenzene
and
Pentachlorobenzene
in
Technical
Atrazine,
Ametryn,
Simazine,
Prometryn,
Prometon,
and
Cyromazine.
Chemical
No.
061001.
Waiver
Request
and
Analytical
Method
Protocol.
From:
S.
Funk
To:
D.
Utterback
Dated:
4/
19/
93
MRID(
s):
None
DP
Barcode(
s):
D169896
Subject:
Reregistration
of
Ametryn.
Ciba­
Geigy
Corp.
90
Day
Response
to
Phase
4
DCI.
Chemical
No.
080801.
From:
S.
Funk
To:
K.
Davis/
T.
Luminello
Dated:
4/
20/
93
MRID(
s):
None
DP
Barcode(
s):
D195429
Subject:
Atrazine
(
Chemical
080803,
Case
0062,
List
A).
Product
Chemistry.
Determination
of
HCB/
PCB
in
Ciba­
Geigy
Technical
(
100­
529).
From:
S.
Funk
To:
R.
Dumas/
D.
Utterback
Dated:
10/
10/
95
MRID(
s):
42925201
