3­
2­
01
MEMORANDUM
SUBJECT:
Oxadiazon.
List
B
Reregistration
Case
2485.
PC
Code
109001.
Product
Chemistry
Chapter
for
the
Reregistration
Eligibility
Decision
[
RED]
Document.
DP
Barcode
D273104.

FROM:
K.
Dockter,
Chemist
Reregistration
Branch
2
Health
Effects
Division
[
7509C]

THRU:
Alan
Nielsen,
Branch
Senior
Scientist
Reregistration
Branch
2
Health
Effects
Division
[
7509C]

TO:
Nancy
McCarroll,
Risk
Assessor
Toxicology
Branch
Health
Effects
Division
[
7509C]

Oxadiazon
[
2­
tert­
butyl­
4­(
2,4­
dichloro­
5­
iospropoxyphenyl)

2­
1,3,4­
oxadiazolin­
5­
one]
is
a
preemergence,
early
postemergence
herbicide
registered
to
control
annual
grasses
and
broadleaf
weeds.

Empirical
formula:
C
15
H
18
Cl
2
N
2
O
3
Molecular
weight:
345.2
CAS
Registry
No.:
19666­
30­
9
PC
Code:
109001
Chemical
structure
by
J.
Punzi
2
A
search
of
REFS
conducted
2/
14/
01
identified
a
single
oxadiazon
MP
registered
under
PC
Code
109001,
the
Aventis
Cropscience
USA
LP
94
%
technical
[
T];
EPA
Reg.
No.
264­
450.
There
are
47
active
end
use
products.
Only
the
Aventis
94%
T
is
subject
to
a
RED.

The
product
chemistry
data
base
is
complete.
However,
the
current
Confidential
Statement
of
Formula
[
CSF],
dated
4/
7/
78,
is
inadequate.
Nominal
concentration
and
upper
limit
must
be
stated
for
all
components.
Additionally,
the
lower
limit
must
be
stated
for
the
a.
i.
The
CSF
must
be
executed
by
the
current
registrant.
The
Series
830
physical
and
chemical
properties
are
given
in
the
table
below.

GLN
MRID
Data
6302
Color
jacket
white
6303
Physical
state
"
crystalline
pwd.

6304
Odor
"
odorless
7200
MP
"
90
C
7300
Bulk
density
41565701
1.3
g/
mL
7840
Water
solubility
jacket
0.0007
g/
L
@
20
C
7950
vp
41230301
7.76x10­
7
mm
Hg
[
gas
satn.]

7550
P
ow
41230302
log
P
=
4.91
6313
Stability
to
normal
and
elevated
temperatures,
metals,
and
metal
ions
41877601
stable
for
30
days
@
55
C;
stable
in
presence
of
aluminum,
iron,
&
tin
pwds.
But
>
5%
loss
in
presence
of
ferric
chloride.

Bibliography
41565701
Chabassol,
Y.;
Hunt,
G.
[
1990]
Oxadiazon­
Specific
Gravity
and
Density
at
20
C:
Study
No.
89­
15.
Unpublished
study
prepared
by
Rhone­
Poulenc
Ag
Co.
16
p.

41230301
Hoffman,
M.
[
1989]
Vapor
Pressure
Determination
of
Oxadiazon:
Project
No.
HLA
6001­
372.
Unpublished
study
prepared
by
Hazelton
Labs.
America,
Inc.
71
p.

41230302
Seymour,
R.;
Hall,
L.
[
1988]
Octanol/
Water
Partition
Coefficient
Determination
for
Oxadiazon;
Report
No.
40434.
Unpublished
study
prepared
by
Rhone­
Poulenc
Ag
Co.
12
p.
3
41877601
Sanders,
J.
[
1991]
Oxadiazon,
Technical
­
Determination
of
Stability;
Lab.
ID
4053­
91­
0061­
AS.
Unpublished
study
prepared
by
Ricerca,
Inc.
102
p.

cc:
List
B
file,
SF,
RF,
Dockter,
N.
McCarroll,
S.
Piper,
S.
Tadayan.
RD\
I
TB/
CEB/
RRB2
Oxadiazon
RED
Team.
7509C:
RRB2:
Rm712N:
57886:
KD/
kd
Oxadiazon
RED
[
9856_
1]
=
D273104.
RED.
wpd.
