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chlorimuron ethyl (DPX F6025) Pesticide Petition Filing 4/98


[Federal Register: April 16, 1998 (Volume 63, Number 73)]
[Notices]               
[Page 18912-18919]
>From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr16ap98-57]

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ENVIRONMENTAL PROTECTION AGENCY

[PF-802; FRL-5782-8]

 
Notice of Filing of Pesticide Petitions

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

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SUMMARY: This notice announces the initial filing of pesticide 
petitions proposing the establishment of regulations for residues of 
certain pesticide chemicals in or on various food commodities.
DATES: Comments, identified by the docket control number PF-802, must 
be received on or before May 18, 1998.
ADDRESSES: By mail submit written comments to: Public Information and 
Records Integrity Branch (7502C), Information Resources and Services 
Division, Office of Pesticides Programs, Environmental Protection 
Agency, 401 M St., SW., Washington, DC 20460. In person bring comments 
to: Rm. 119, CM #2, 1921 Jefferson Davis Highway, Arlington, VA.
    Comments and data may also be submitted electronically to: opp-
docket@epamail.epa.gov. Follow the instructions under ``SUPPLEMENTARY 
INFORMATION.'' No confidential business information should be submitted 
through e-mail.
    Information submitted as a comment concerning this document may be 
claimed confidential by marking any part or all of that information as 
``Confidential Business Information'' (CBI). CBI should not be 
submitted through e-mail. Information marked as CBI will not be 
disclosed except in accordance with procedures set forth in 40 CFR part 
2. A copy of the comment that does not contain CBI must be submitted 
for inclusion in the public record. Information not marked confidential 
may be disclosed publicly by EPA without prior notice. All written 
comments will be available for public inspection in Rm. 119 at the 
address given above, from 8:30 a.m. to 4 p.m., Monday through Friday, 
excluding legal holidays.

FOR FURTHER INFORMATION CONTACT: By mail: Product Manager (PM-10), 
Marion Johnson, Registration Division (7505C), Office of Pesticide 
Programs, Environmental Protection Agency, 401 M St., SW., Washington, 
DC 20460. Office location and telephone number: Rm. 208, CM #2, 1921 
Jefferson Davis Hwy, Arlington, VA 22202, 703-305-6788, e-mail: 
johnson.marion@epamail.epa.gov.

SUPPLEMENTARY INFORMATION: EPA has received a pesticide petition as 
follows proposing the establishment and/or amendment of regulations for 
residues of certain pesticide chemicals in or on various food 
commodities under section 408 of the Federal Food, Drug, and Comestic 
Act (FFDCA), 21 U.S.C. 346a. EPA has determined that the petition 
contains data or information regarding the elements set forth in 
section 408(d)(2); however, EPA has not fully evaluated the sufficiency 
of the submitted data at this time or whether the data supports 
granting of the petition. Additional data may be needed before EPA 
rules on the petition.
    The official record for this notice of filing, as well as the 
public version, has been established for this notice of filing under 
docket control number [PF-802] (including comments and data submitted 
electronically as described below). A public version of this record, 
including printed, paper versions of electronic comments, which does 
not include any information claimed as CBI, is available for inspection 
from 8:30 a.m. to 4 p.m., Monday through Friday, excluding legal 
holidays. The official record is located at the address in 
``ADDRESSES'' at the beginning of this document.
    Electronic comments can be sent directly to EPA at:
    opp-docket@epamail.epa.gov


    Electronic comments must be submitted as an ASCII file avoiding the 
use of special characters and any form of encryption. Comment and data 
will also be accepted on disks in Wordperfect 5.1/6.1 or ASCII file 
format. All comments and data in electronic form must be identified by 
the docket control number [PF-802] and appropriate petition number. 
Electronic comments on this notice may be filed online at many Federal 
Depository Libraries.

List of Subjects

    Environmental protection, Agricultural commodities, Food additives, 
Feed additives, Pesticides and pests, Reporting and recordkeeping 
requirements.


[[Page 18913]]


    Dated: April 3, 1998.

James Jones,

Director, Registration Division, Office of Pesticide Programs.

Summaries of Petitions

    Petitioner summaries of the pesticide petitions are printed below 
as required by section 408(d)(3) of the FFDCA. The summaries of the 
petitions were prepared by the petitioners and represent the views of 
the petitioners. EPA is publishing the petition summaries verbatim 
without editing them in any way. The petition summary announces the 
availability of a description of the analytical methods available to 
EPA for the detection and measurement of the pesticide chemical 
residues or an explanation of why no such method is needed.

E.I. duPont de Nemours and Company

PP 8F4948

    EPA has received a pesticide petition (PP 8F4948) from E. I. du 
Pont de Nemours and Company (DuPont), P.O. Box 80038, Wilmington, DE 
19880-0038, proposing pursuant to section 408(d) of the Federal Food, 
Drug and Cosmetic Act, 21 U.S.C. 346a(d), to amend 40 CFR part 180 by 
establishing a tolerance for residues of the insecticide DPX-MP062, 
(R,S)-methyl 7-chloro-2,5-dihydro-2-[[(methoxycarbonyl)[4-
(trifluoromethoxy)phenyl]   amino]carbonyl]indeno[1,2-
e][1,3,4]oxadiazine-4a(3H)-carboxylate, in/on the raw agricultural 
commodities as follows: pome fruit at 2.0 parts per million (ppm), 
apple pomace at 6.0 ppm, head and stem brassicas at 10.0 ppm, 
cottonseed at 3.0 ppm, cotton gin trash at 15.0 ppm, leaf lettuce at 
20.0 ppm, head lettuce at 7.0 ppm, fruiting vegetables at 0.70 ppm, 
sweet corn kernel at 0.02 ppm, sweet corn forage at 20.0 ppm, and sweet 
corn stover at 25.0 ppm, meat 0.02 ppm, milk at 0.10 ppm, cattle kidney 
at 0.05 ppm; and by establishing a tolerance for residues of the 
insecticide DPX-MP062, (R,S)-methyl 7-chloro-2,5-dihydro-2-
[[(methoxycarbonyl)[4-(trifluoromethoxy)phenyl]  amino]carbonyl]  
indeno[1,2-e][1,3,4]oxadiazine-4a(3H)-carboxylate and its metabolite 
(IN-JT333), methyl 7-chloro-2,5-dihydro-2-[[[4-
(trifluoromethoxy)phenyl]  amino]carbonyl]indeno[1,2-
e][1,3,4]oxadiazine-4a(3H)-carboxylate, in/on milk fat at 0.75 ppm and 
cattle fat at 0.75 ppm. Three analytical enforcement methods are 
available for determining these plant and animal residues; they are 
HPLC with UV detection, GC-MSD and HPLC column-switching with UV 
detection. EPA has determined that the petition contains data or 
information regarding the elements set forth in section 408(d)(2) of 
the FFDCA; however, EPA has not fully evaluated the sufficiency of the 
submitted data at this time or whether the data supports granting of 
the petition. Additional data may be needed before EPA rules on the 
petition.

A. Residue Chemistry

    DPX-MP062 and DPX-JW062 are mixtures of two isomers (DPX-KN128 and 
IN-KN127). Only one of the isomers, DPX-KN128, has insecticidal 
activity. JW062 is a 50:50 mixture of the isomers. DPX-MP062 is 
enriched to 75:25 for the insecticidally active DPX-KN128. Registration 
is being sought for DPX-MP062. Some DPX-JW062 data is relevant and is 
being included to support the registration.
    Since the insecticidal efficacy is based on the concentration of 
DPX-KN128, the application rates have been normalized on a DPX-KN128 
basis. The proposed tolerance expression includes both DPX-KN128 and 
IN-KN127 and the residue method does not distinguish between the 
enantiomers, therefore residues are reported as the sum of DPX-KN128 
combined with IN-KN127. Residues of DPX-KN128 combined with IN-KN127, 
whether derived from DPX-MP062 or DPX-JW062, will be referred to as 
``KN128/KN127''.
    1. Plant metabolism. The metabolism of DPX-MP062 in plants is 
adequately understood to support these tolerances. Plant metabolism 
studies in cotton, lettuce, grapes and tomatoes showed no significant 
metabolites. The only significant residue was parent compound.
    2. Analytical method. One plant residue enforcement method detects 
and quantitates DPX-MP062 in cotton and sweet corn matrices by HPLC 
with UV detection. The other plant residue enforcement method detects 
and quantitates DPX-MP062 in various matrices including lettuce, 
tomato, pepper, cabbage, broccoli, cauliflower, apple, pear, grape, 
cottonseed, tomato and apple processed commodity samples by GC-MSD. The 
analytical method for detecting and quantitating DPX-MP062 in animal 
matrices including whole and skim milk, cream, fat, muscle, liver and 
kidney is an HPLC column-switching method using UV detection. The limit 
of quantitation in each method allows monitoring of crops and animal 
matrices with DPX-MP062 residues at or above the levels proposed in 
these tolerances.
    3. Magnitude of residues--i. Pome fruit. The magnitude and decline 
of residues of KN128/KN127 were determined on apple and pear, the 
representative commodities of the pome fruit crop group.
    ii. Pome fruit - apple. Residue studies were conducted with a total 
of 21 trials in 1995 and 1996. Studies in 1995 were done with DPX-
JW062. Studies in 1996 were conducted with DPX-MP062 with concurrent 
trials of DPX-JW062 and DPX-MP062 in a number of locations.
    In 1995, DPX-JW062 was applied as a 60% water dispersable granule 
to 12 test sites in New York, Pennsylvania, North Carolina, Michigan, 
Utah, California, Washington and Oregon. DPX-JW062 was applied as four 
broadcast applications at the maximum per application rate of 0.133 lb. 
DPX-KN128/acre for a maximum seasonal use rate of 0.532 lb. a.i./acre. 
Applications were made approximately 7-days apart. The target PHI was 
28 days. Residues of KN128/KN127 at the target PHI of 28 days ranged 
from 0.21 - 1.1 ppm.
    In 1996, a total of 9 trials were conducted with DPX-MP062 and DPX-
JW062. DPX-MP062 was applied as a 30% water dispersable granule to 5 
test sites in New York, Michigan, California, and Washington. DPX-MP062 
was applied as four broadcast applications at the maximum per 
application rate of 0.133 lb. DPX-KN128/acre for a maximum seasonal use 
rate of 0.532 lb. a.i./acre. DPX-JW062 was applied as a 60% water 
dispersable granule in concurrent trials at 4 test sites. Applications 
were made approximately 7-days apart. The target PHI was 28-days. 
Residues of KN128/KN127 for all sites at the target PHI of 28-days 
ranged from 0.084 - 0.89 ppm. Comparable residues of KN128/KN127 were 
found on apples treated with either test substance in concurrent 
trials.
    4. Pome fruit - apple, process fractions. A study was conducted to 
determine the magnitude and concentration of KN128/KN127 in apple and 
its processed fractions, juice and wet pomace, following application of 
DPX-MP062 Experimental Insecticide. Residues were determined as the sum 
of the isomers and are reported as KN128/KN127. DPX-MP062 was applied 
as a 30% water dispersable granule in four broadcast applications at 1x 
and 5x the proposed maximum seasonal rate of 0.535 lb. DPX-KN128/acre. 
The application interval was 5-days and the pre-harvest interval was 3-
days. When applied at 5x the maximum seasonal use rate, quantifiable 
residues KN128/KN127 were not detected in juice. KN128/KN127 
concentrated in wet

[[Page 18914]]

pomace. The concentration factor in wet pomace was 2.6x.
    5. Pome fruit - pear. In 1996, DPX-MP062 was applied as a 30% water 
dispersable granule to 6 test sites in New York, California and 
Washington. DPX-MP062 was applied as four broadcast applications at the 
maximum per application rate of 0.133 lb. DPX-KN128/acre for a maximum 
seasonal use rate of 0.532 lb. a.i./acre. Applications were made 
approximately 7-days apart. The target PHI was 28-days. Residues of 
KN128/KN127 at the target PHI of 28 days ranged from 0.035 - 0.12 ppm. 
Residues of KN128/KN127 on pears were within the range of KN128/KN127 
residues on apples resulting from application of DPX-MP062.
    6. Fruiting vegetables. The magnitude and decline of residues of 
KN128/KN127 were determined on pepper and tomato, the representative 
commodities of the fruiting vegetable crop group.
    7. Fruiting vegetables- pepper. In 1996, DPX-MP062 was applied as a 
30% water dispersable granule to 9 test sites in Florida, North 
Carolina, Ohio, Texas and California. DPX-MP062 was applied as four 
broadcast applications at the maximum per application rate of 0.067 lb. 
DPX-KN128/acre for a maximum seasonal use rate of 0.268 lb. a.i./acre. 
Applications were made approximately 5-days apart. The target PHI was 
3-days. Residues of KN128/KN127 at the target PHI of 3-days ranged 
<0.02 - 0.08 ppm in bell peppers and >0.02 - 0.10 ppm in non-bell 
peppers.
    8. Fruiting vegetables - tomato. Residue studies were conducted 
with a total of 19 trials in 1995 and 1996. Studies in 1995 were done 
with DPX-JW062. Studies in 1996 were conducted with DPX-MP062 with 
side-by-side comparisons of DPX-JW062 and DPX-MP062 in a number of 
locations. In 1995, DPX-JW062 was applied as a 60% water dispersable 
granule to 12 test sites in California, Florida, Maryland and 
Pennsylvania. DPX-JW062 was applied as four broadcast applications at 
the maximum per application rate of 0.067 lb. DPX-KN128/acre for a 
maximum seasonal use rate of 0.268 lb. a.i./acre. Applications were 
made approximately 5 days apart. The target PHI was 3-days. Residues of 
KN128/KN127 at the target PHI of 3-days ranged from 0.033 - 0.43 ppm.
    In 1996, a total of 7 trials were conducted with DPX-MP062 and DPX-
JW062. DPX-MP062 was applied as a 30% water dispersable granule to 4 
test sites in Florida, Indiana and California. DPX-MP062 was applied as 
four broadcast applications at the maximum per application rate of 
0.067 lb. DPX-KN128/acre for a maximum seasonal use rate of 0.27 lb. 
a.i./acre. DPX-JW062 was applied as a 60% water dispersable granule in 
concurrent trials at 3 test sites. Applications were made approximately 
5-days apart. The target PHI was 3-days. Residues of KN128/KN127 for 
all sites at the target PHI of 3-days for all sites ranged from <0.02 - 
0.16 ppm. Comparable residues of KN128/KN127 were found on tomatoes 
treated with either test substance in concurrent trials.
    9. Fruiting vegetables - tomato process fractions. A study was 
conducted which determined the magnitude and concentration of KN128/
KN127 in tomatoes and its processed fractions, puree and paste, 
following application of DPX-MP062 Experimental Insecticide. DPX-MP062 
is a 75:25 isomer mixture which contains the isomers DPX-KN128 and IN-
KN127. DPX-MP062 was applied as a 30% water dispersable granule in four 
broadcast applications at 1x and 5x the proposed maximum seasonal rate 
of 0.535 lb. DPX-KN128/acre. The application interval was 5-days and 
the pre-harvest interval was 3-days. When applied at 5x the maximum 
seasonal use rate, DPX-MP062 did not concentrate in puree and 
concentrated slightly in paste. Concentration factors in puree and 
paste were 0.5x and 1.4x respectively.
    10. Cole crops-- i. Head and stem brassica. The magnitude and 
decline of residues of KN128/KN127 were determined on broccoli and 
cabbage, the representative commodities of the head and stem brassica 
sub group of the cole crop group.
    ii. Broccoli. Residue studies were conducted with a total of 10 
trials in 1995 and 1996. Studies in 1995 were done with DPX-JW062. 
Studies in 1996 were conducted with DPX-MP062 with side-by-side 
comparisons of DPX-JW062 and DPX-MP062 in a number of locations.
    In 1995, DPX-JW062 was applied as a 60% water dispersable granule 
to 6 test sites in Arizona, California, Oregon and Texas. DPX-JW062 was 
applied as four broadcast applications at the maximum per application 
rate of 0.067 lb. DPX-KN128/acre for a maximum seasonal use rate of 
0.268 lb. a.i./acre. Applications were made approximately 3-days apart. 
The target PHI was 3-days. Residues of KN128/KN127 for all sites at the 
target PHI of 3-days ranged from 0.28 - 2.5 ppm .
    In 1996, a total of 4 trials were conducted with DPX-MP062 and DPX-
JW062. DPX-MP062 was applied as a 30% water dispersable granule to 2 
test sites in California and Texas. DPX-MP062 was applied as four 
broadcast applications at the maximum per application rate of 0.067 lb. 
DPX-KN128/acre for a maximum seasonal use rate of 0.268 lb. a.i./acre. 
DPX-JW062 was applied as a 60% water dispersable granule in concurrent 
trials at 2 test sites. Applications were made approximately 3-days 
apart. The target PHI was 3-days. Residues of KN128/KN127 for all sites 
at the target PHI of 3 days ranged from 0.23 - 0.8 ppm. Comparable 
residues of KN128/KN127 were found on broccoli treated with either test 
substance in concurrent trials.
    11. Cabbage. Residue studies were conducted with a total of 12 
sites in 1995 and 1996. Studies in 1995 were done with DPX-JW062. 
Studies in 1996 were conducted with DPX-MP062 with side-by-side 
comparisons of DPX-JW062 and DPX-MP062 in a number of locations.
    In 1995, DPX-JW062 was applied as a 60% water dispersable granule 
to 6 test sites in California, Maryland, Florida, Texas, New York, and 
Wisconsin. DPX-JW062 was applied as four broadcast applications at the 
maximum per application rate of 0.067 lb. DPX-KN128/acre for a maximum 
seasonal use rate of 0.268 lb. a.i./acre. Applications were made 
approximately 3-days apart. The target PHI was 3-days. Residues of 
KN128/KN127 at the target PHI of 3-days ranged from 0.60 - 4.00 ppm 
(wrapper leaves attached) and <0.02 - 0.16 ppm (wrapper leaves 
removed).
    In 1996, a total of 6 trials were conducted with DPX-MP062 and DPX-
JW062. DPX-MP062 was applied as a 30% water dispersable granule to 4 
test sites in Florida, Wisconsin, and California. DPX-MP062 was applied 
as four broadcast applications at the maximum per application rate of 
0.067 lb. DPX-KN128/acre for a maximum seasonal use rate of 0.268 lb. 
a.i./acre. DPX-JW062 was applied as a 60% water dispersable granule in 
concurrent trials at 2 test sites. Applications were made approximately 
3-days apart. The target PHI was 3-days. Residues of KN128/KN127 for 
all sites at the target PHI of 3-days ranged from 0.14 to 6.4 ppm 
(wrapper leaves attached) and <0.020 to 0.32 ppm (wrapper leaves 
removed). Comparable residues of KN128/KN127 were found on cabbage 
treated with either test substance in concurrent trials.
    12. Lettuce - head and leaf. The magnitude and decline of residues 
of KN128/KN127 were determined on head and leaf lettuce. Residue 
studies were conducted with a total of 20 trials in 1995 and 1996. 
Studies in 1995 were done with DPX-JW062. Studies in 1996

[[Page 18915]]

were conducted with DPX-MP062 with side-by-side comparisons of DPX-
JW062 and DPX-MP062 in a number of locations.
    In 1995, DPX-JW062 was applied as a 60% water dispersable granule 
to 9 test sites in Arizona, California, Florida and Maryland. Head 
lettuce was grown at 5 sites, leaf lettuce at 4. DPX-JW062 was applied 
as four broadcast applications at the maximum per application rate of 
0.067 lb. DPX-KN128/acre for a maximum seasonal use rate of 0.268 lb. 
a.i./acre. Applications were made approximately 3 days apart. The 
target PHI was 3 days. On head lettuce, residues of KN128/KN127 at the 
target PHI of 3 days ranged from 0.59 - 4.7 ppm (wrapper leaves 
attached) and 0.022 - 2.1 ppm (wrapper leaves removed). On leaf 
lettuce, residues of KN128/KN127 at the target PHI of 3 days ranged 
from 3.2 - 13 ppm.
    In 1996, a total of 11 trials were conducted with DPX-MP062 and 
DPX-JW062. DPX-MP062 was applied as a 30% water dispersable granule to 
6 (4 for head lettuce and 2 for leaf lettuce) test sites in Florida, 
Maryland, Arizona, and California. DPX-MP062 was applied as four 
broadcast applications at the maximum per application rate of 0.067 lb. 
DPX-KN128/acre for a maximum seasonal use rate of 0.268 lb. a.i./acre. 
DPX-JW062 was applied as a 60% water dispersable granule in concurrent 
trials at 5 test sites (3 for head lettuce and 2 for leaf lettuce). 
Applications were made approximately 3 days apart. The target PHI was 3 
days. On head lettuce, residues of KN128/KN127 for all sites at the 
target PHI of 3 days ranged from 0.18 - 3.7ppm (wrapper leaves 
attached) and <0.02 - 0.74 ppm (wrapper leaves removed). On leaf 
lettuce, residues of KN128/KN127 at the target PHI of 3 days ranged 
from 2.8 - 7.9 ppm. Comparable residues of KN128/KN127 were found on 
lettuce treated with either test substance in concurrent trials.
    13. Sweet corn. The magnitude and decline of residues of KN128/
KN127 were determined on sweet corn. Residue studies were conducted 
with a total of 19 trials in 1995 and 1996. Studies in 1995 were done 
with DPX-JW062. Studies in 1996 were conducted with DPX-MP062 with 
side-by-side comparisons of DPX-JW062 and DPX-MP062 in a number of 
locations.
    In 1995, DPX-JW062 was applied as a 60% water dispersable granule 
to 9 test sites in New York, Maryland, Florida, Minnesota, Illinois, 
California, Oregon, and Washington. DPX-JW062 was applied as four 
broadcast applications at the maximum per application rate of 0.067 lb. 
DPX-KN128/acre for a maximum seasonal use rate of 0.268 lb. a.i./acre. 
Applications were made approximately 3-days apart. The target PHI was 
3-days for kernels plus cob with husks removed (K + CWHR) and 35-days 
for stover. The highest residue found in K + CWHR was 0.012 ppm. 
Residues of KN128/KN127 detected in 3-day forage samples ranged from 
1.7 ppm to 13 ppm. Residues of KN128/KN127 detected in 35-day stover 
ranged from 0.86 to 20 ppm. ppm.
    In 1996, a total of 10 trials were conducted with DPX-MP062 and 
DPX-JW062. DPX-MP062 was applied as a 30% water dispersable granule to 
6 test sites in Maryland, Illinois, Minnesota, Indiana, Wisconsin, and 
California. DPX-MP062 was applied as four broadcast applications at the 
maximum per application rate of 0.067 lb. DPX-KN128/acre for a maximum 
seasonal use rate of 0.268 lb. a.i./acre. DPX-JW062 was applied as a 
60% water dispersable granule in concurrent trials at 4 test sites. 
Applications were made approximately 3- days apart. The target PHI was 
3-days. No quantifiable residues were found in 3-day samples of K + 
CWHR. Residues of KN128/KN127 detected in 3-day forage samples for all 
sites ranged from 0.95 ppm to 10 ppm. Residues of KN128/KN127 detected 
in 35-day stover for all sites ranged from 1.5 to 13 ppm. Comparable 
residues of KN128/KN127 were found on sweet corn treated with either 
test substance in concurrent trials.
    14. Cotton. The magnitude and decline of residues of KN128/KN127 
were determined on cotton. Residue studies were conducted with a total 
of 19 trials in 1995 and 1996. Studies in 1995 were done with DPX-
JW062. Studies in 1996 were conducted with DPX-MP062 with side-by-side 
comparisons of DPX-JW062 and DPX-MP062 in a number of locations.
    In 1995, DPX-JW062 was applied as a 35% suspension emulsion to 8 
test sites in North Carolina, Mississippi, Arkansas, Texas, Oklahoma, 
Arizona, and California. DPX-JW062 was applied as four broadcast 
applications at the maximum per application rate of 0.133 lb. DPX-
KN128/acre for a maximum seasonal use rate of 0.532 lb. a.i./acre. 
Applications were made approximately 5-days apart. The target PHI was 
14-days. Residues of KN128/KN127 on undelinted seed cotton at the 
target PHI of 14-days ranged from 0.13- 1.9 ppm.
    In 1996, a total of 11 trials were conducted with DPX-MP062 and 
DPX-JW062 DPX-MP062 was applied as a 15% suspension concentrate to 7 
test sites in Georgia, Mississippi, Texas, Oklahoma and California. 
DPX-MP062 was applied as four broadcast applications at the maximum per 
application rate of 0.133 lb. DPX-KN128/acre for a maximum seasonal use 
rate of 0.532 lb. a.i./acre. DPX-JW062 was applied as a 60% water 
dispersable granule in concurrent trials at 4 test sites. Applications 
were made approximately 5 days apart. The target PHI was 14-days. 
Residues of KN128/KN127 for all sites at the target PHI of 14-days 
ranged from 0.033 - 1.0 ppm in undelinted seed and 2.9 - 12 ppm in 
cotton gin trash. Comparable residues of KN128/KN127 were found on 
cotton treated with either test substance in concurrent trials.
    15. Cotton - process fractions. A study was conducted to determine 
the magnitude and concentration of KN128/KN127 in cotton and its 
processed fractions, hulls, meal, and refined oil following application 
of DPX-MP062 Experimental Insecticide. DPX-MP062 is a 75:25 isomer 
mixture which contains the isomers DPX-KN128 and IN-KN127. DPX-KN128 is 
the insecticidally active isomer. Residues were determined as the sum 
of the isomers and are reported as KN128/KN127. DPX-MP062 was applied 
as a 15% suspension-emulsion in four broadcast applications at 1X and 
5x the proposed maximum seasonal rate of 0.535 lb. DPX-KN128/acre. The 
application interval was 5-days and the pre-harvest interval was 14-
days. When applied at 5x the maximum seasonal use rate, KN128/KN127 did 
not concentrate in any process fraction and quantifiable residues were 
not detected in meal. Concentration factors in hulls and refined oil 
were 0.03X and 0.04X respectively.
    16. Livestock animal metabolism. Animal metabolism has been studied 
in the rat, hen, and cow and is well understood. In contrast to crops, 
DPX-MP062 is extensively metabolized in animals.
    17. Poultry. In poultry, hens were fed at 10 ppm/day for 5 days, 
87-88% of the total administered dose was excreted; parent comprised 
51-54% of the total dose in excreta. Concentration of residues in eggs 
were low, 0.3-0.4 of the total dose, as was the concentration of 
residues in muscle, 0.2% of the total dose. Parent and IN-JT333 were 
not detected in egg whites; only insecticidally inactive metabolites 
were identified. Parent and IN-JT333 were found in egg yolks; however, 
their concentrations were very low-0.01-0.02 ppm. Concentrations of 
parent and IN-JT333 in muscle were at or below the limit of 
quantitation, (LOQ) (0.01 ppm). A poultry feeding study was not 
conducted because finite concentrations of residues would not be 
expected based on the low concentration of residues in

[[Page 18916]]

the metabolism study and the approximate 200-fold excess under which 
the metabolism study was conducted compared to a proposed 1X feeding 
dose. Further, the only poultry feed item that could contain DPX-MP062 
residues is cotton meal. In a cotton processing study run at 5X, no 
detectable residues of DPX-MP062 were seen. Thus no tolerances are 
proposed for poultry or eggs.
    18. Cattle. For the cow study, the cattle were fed at 10 ppm/day 
for 5-days; approximately 20% of the total administered dose was 
excreted in urine and 53-60% was excreted in feces in 5-days. Four-
tenths to 1.2% of the total dose in urine was parent indicating 
extensive metabolism; parent represented 46-68% of the fecal activity. 
Thus, most residues were not absorbed; those residues that were 
absorbed were extensively metabolized. Less than 1% of the total 
administered dose was in milk, most of which was parent compound. The 
insecticidally active metabolite IN-JT333 was not found in milk. 
Residues in muscle represented less than 0.01% of the total 
administered dose most of which was parent. IN-JT333 was not detected 
in muscle. No other metabolites were seen above 10% of the dose, thus 
only parent and IN-JT333 were monitored in the cattle feeding study.
    Contribution of feed items to the cattle diet.
    The Highest Average Field Trial (HAFT) value (based upon data from 
field residue trials for sweet corn and apples (DuPont Reports AMR 
3291-95, AMR 3737-96, AMR 3292-95, and AMR 3950-96) was multiplied by a 
correction factor for drying, a concentration factor, if appropriate, 
and the percentage of the cattle diet for the feed item. The 
contribution to the cattle diet in ppm was then calculated:

--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                     Calculated                           Contribution  
                        Feed Item                                 HAFT          Drying Factor      Residue (ppm)          % Diet             (ppm)      
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sweet corn forage........................................                 10               0.48              20.83                 50              10.42
Sweet corn cannery waste.................................                 10                0.3              33.33                 30              10.00
Apple pomace.............................................                2.6                0.4               6.50                 20               1.30
    Total................................................  .................  .................  .................  .................              21.72
--------------------------------------------------------------------------------------------------------------------------------------------------------

    19. Cattle feeding study. A cattle feeding study was conducted with 
DPX-MP062 at doses of 7.5 ppm, 22.5 and 75 ppm which were based on 
preliminary residue values available at the time. Based on final 
residue values for the respective commodities contributing to the 
cattle diet, the 22.5 ppm feeding level is an appropriate feeding level 
from which to propose tolerances.
    KN128/KN127 concentrations at the 22.5 ppm feeding level were 0.053 
ppm for whole milk, 0.018 ppm for skim milk and 0.58 ppm for cream. The 
mean KN128/KN127 concentrations were proportional to the dosing level 
in whole milk, skim milk and cream. IN-JT333 concentrations at the 22.5 
ppm feeding level were below the LOQ for whole milk and skim milk. The 
concentration of IN-JT333 in cream was 0.022 ppm. The mean IN-JT333 
concentrations were proportional to the dosing level in cream.
    KN128/KN127 and IN-JT333 concentrations at the 22.5 ppm feeding 
level were below the level of quantitation (LOQ) for all tissues, 
except fat (0.45 ppm, KN128/KN127 and 0.03 ppm IN-JT333) and kidney 
(0.017 ppm KN128/KN127), throughout 28 days of dosing. The mean KN128/
KN127 residues in muscle, fat, liver, and kidney samples were 
proportional to the dosing level. The meanIN-JT333 residues in fat were 
proportional to the dosing level.

B. Toxicological Profile

    1. Acute toxicity. Based on EPA criteria, DPX-MP062 should be 
classified as follows for Toxicity Categories:

----------------------------------------------------------------------------------------------------------------
                Title                        Test Animal                Results                  Category       
----------------------------------------------------------------------------------------------------------------
Oral.................................                      Rat        LD<INF>501730 mg/kg(M)                         
                                                                       LD<INF>50268 mg/kg(F)              Category II
Dermal...............................                      Rat          LD<INF>50>5000 mg/kg              Category IV
Inhalation...........................                      Rat   LC<INF>50>5.4 mg/L (M) LC<INF>50                         
                                                                           4.2 mg/L (F)              Category IV
Eye irritation.......................                   Rabbit  Effects reversed within                         
                                                                              72 hours.             Category III
Dermal irritation....................                   Rabbit            No irritation              Category IV
Dermal sensitization.................               Guinea pig               Sensitizer  .......................
----------------------------------------------------------------------------------------------------------------

    Formulated products are slightly less acutely toxic than DPX-MP062.
    DPX-MP062 exhibited acute neurotoxic effects (decreased forelimb 
grip strength, decreased foot splay, and some evidence of slightly 
reduced motor activity), but only at the highest doses tested. The NOEL 
was 100 mg/kg for males and 50 mg/kg for females.
    2. Genotoxicity. DPX-MP062 has shown no genotoxic activity in the 
following listed in-vitro and in-vivo tests:
    i. Ames-- Negative
    ii.  In-vitro mammalian gene mutation (CHO/HGPRT)-- Negative
    iii.  In-vitro unscheduled DNA synthesis-- Negative
    iv.  In-vitro chromosomal aberration-- Negative
    v.  In-vivo mouse micronucleus-- Negative
    3. Reproductive and developmental toxicity. The results of a series 
of studies indicated that there were no reproductive, developmental or 
teratogenic hazards associated with the use of DPX-MP062.
    In a 2-generation rat reproduction study, the parental NOEL was 1.3 
and 1.5 mg/kg/day for males and females, respectively. The parental 
NOEL was based on observations of reduced weight gain and food 
consumption for the higher concentration groups of the F0 generation 
and potential treatment-related changes in spleen weights for the 
higher groups of the F1 generation. There was no effect on mating or 
fertility. The NOEL for fertility and reproduction was, 6.4 and 6.9 mg/
kg/day for males and females, respectively.

[[Page 18917]]

 The fetal (developmental) NOEL was 1.3 and 1.5 mg/kg/day for males and 
females, respectively, and based on the reduced mean pup weights noted 
for the F1 litters of the higher concentration groups. The effects on 
pup weights occurred only at a maternal effect level and may have been 
due to altered growth and nutrition in the dams.
    In studies conducted to evaluate developmental toxicity potential, 
DPX-MP062 was neither teratogenic nor uniquely toxic to the conceptus 
(i.e., not considered a developmental toxin). Developmental studies 
conducted in rats and rabbits demonstrated that the rat was more 
susceptible than the rabbit to the maternal and fetal effects of DPX-
MP062. Developmental toxicity was observed only in the presence of 
maternal toxicity. The NOEL for maternal and fetal effects in rats was 
2 mg/kg/day based on body weight effects and decreased food consumption 
at 4 mg/kg/day. The NOEL for developmental effects in fetuses was >4 
mg/kg/day. In rabbits, the maternal and fetal NOELS were 500 mg/kg/day 
based on body weight effects (and in dams, decreased food consumption).
    4. Subchronic toxicity. Subchronic (90-day) feeding studies were 
conducted with rats, mice, and dogs.
    In a 90-day feeding study in rats, the NOEL was 6.01 and 2.13 mg/
kg/day for males and females, respectively. In male rats, the NOEL was 
based on decreased body weight and nutritional parameters, mild 
hemolytic anemia and decreased total protein and globulin 
concentration. In female rats, the NOEL was based on decreased body 
weight and food efficiency. Female rats also had compound related 
mortality, clinical signs of toxicity, and mild hemolytic anemia.
    In a subchronic neurotoxicity study in rats, there was no evidence 
of neurotoxicity at 11.9 and 6.09 mg/kg/day, the highest dose tested 
for males and females, respectively. The standard subchronic rat study 
showed equivocal evidence of neurotoxicity (i.e., ataxia and tremors) 
but only in moribund animals.
    The subchronic NOEL in dogs (2/5 mg/kg/day, M/F) was also based on 
hemolytic anemia. Erythrocyte values for most dogs were within a range 
that would be considered normal for dogs in a clinical setting.
    Mice were less sensitive to DPX-MP062 than the rats or dogs. NOELs 
(23/16 mg/kg/day, M/F) were based on body weight and nutritional 
effects, as well as clinical signs suggestive of neurotoxicity.
    In a 28-day repeated dose dermal study, the NOEL was 1,000 mg/kg/
day based on the hemolytic anemia observed in the 2,000 mg/kg/day group 
females.(being revised).
    5. Chronic toxicity. Chronic studies with DPX-MP062 were conducted 
on rats, mice, and dogs to determine oncogenic potential and/or chronic 
toxicity of the compound. Effects generally similar to those observed 
in the 90-day studies were seen in the chronic studies. DPX-MP062 was 
not oncogenic.
    The chronic NOEL in male rats was 2.4 mg/kg/day based on body 
weight and nutritional effects at 5 mg/kg/day and above. In females, 
the NOEL of 2.13 mg/kg/day was based on body weight and nutritional 
changes, as well as biologically significant hematologic changes at 3.6 
mg/kg/day and above. Hemolytic effects were present only through the 
18-month evaluation. The regenerative nature of DPX-MP062-induced 
hemolytic anemia was demonstrated by the absence of significant changes 
in indicators of circulating erythrocyte mass at the 24-month 
evaluation.
    In mice, the chronic NOEL of 2.63 mg/kg/day for males was based on 
deceased body weight and weight gain effects and food efficiency at 
13.8 mg/kg/day and above. The NOEL for females was 3.99 mg/kg/day based 
on body weight and nutritional effects, neurotoxicity, and mortality at 
20.3 mg/kg/day.
    In dogs, the chronic NOEL was about 1 mg/kg/day in males and 
females based on hemolytic effects similar to those seen in the 
subchronic dog study. The biological significance of changes at the 
next highest dose was equivocal because changes in circulating 
erythrocyte mass at that concentration (2.3 mg/kg/day and 2.4 mg/kg/day 
for males and females, respectively) were within historical control 
ranges and were not associated with changes in erythrocyte indices, 
reticulocyte counts, or platelet counts.
    6. Animal metabolism. In rats, DPX-MP062 was readily absorbed at 
low dose (5 mg/kg)but saturated at the high dose (150 mg/kg). DPX-MP062 
was metabolized extensively, based on very low excretion of parent 
compound in bile and extensive excretion of metabolized dose in the 
urine and feces. Some parent compound remained unabsorbed and was 
excreted in the feces. No parent compound was excreted in the urine. 
The retention and elimination of the metabolite IN-JT333 from fat 
appeared to be the overall rate determining process for elimination of 
radioactive residues from the body. Metabolites in urine were cleaved 
products (containing only one radiolabel),while the major metabolites 
in the feces retained both radiolabels. Major metabolic reactions 
included hydroxylation of the indanone ring, hydrolysis of the 
carboxylmethyl group from the amino nitrogen and the opening of the 
oxadiazine ring which gave rise to cleaved products. Metabolites were 
identified by mass spectral analysis, NMR, UV and/or by comparison to 
standards chemically synthesized or produced by microsomal enzymes.
    7. Metabolite toxicology. The only metabolite of significance is 
IN-JT333 which is formed through animal and soil metabolism although 
only at levels of approximately 15% or less. Direct dietary exposure to 
IN-JT333 is only expected to occur as trace residues in milk fat and 
animal fat.
    Other Potential Toxicology Considerations - Endocrine Modulation 
Chronic, lifespan, and multigenerational bioassays in mammals and acute 
and subchronic studies on aquatic organisms and wildlife did not reveal 
endocrine effects. Any endocrine related effects would have been 
detected in this definitive array of required tests. The probability of 
any such effect due to agricultural uses of DPX-MP062 is negligible.

C. Aggregate Exposure

    DPX-MP062 is a new insecticide with proposed uses on the commercial 
crops pome fruit, head & stem brassicas, sweet corn, cotton, head 
lettuce, leaf lettuce and fruiting vegetables. There are no residential 
uses.
    1. Dietary exposure. The chronic RfD of 0.01 mg/kg bw/day is based 
on a NOEL of 1.1 mg/kg bw/day from the 1-year dog feeding study and an 
uncertainty factor of 100. The acute NOEL of 2 mg/kg bw/day is based 
upon weight loss seen at the 4 mg/kg bw/day level in a rat 
developmental study. Since it could be argued that weight loss is not 
an acute effect, it is likely that the acute NOEL is much higher than 2 
mg/kg bw/day.
    2. Food-- i. Chronic dietary exposure assessment. Chronic dietary 
exposure resulting from the proposed use of DPX-MP062 on apples, pears, 
cotton, broccoli, cabbage, cauliflower, lettuce, sweet corn, peppers, 
and tomatoes is well within acceptable limits for all sectors of the 
population. The Chronic Module of the Dietary Exposure Evaluation Model 
(DEEM, Novigen Sciences, Inc., 1997 Version 5.21) was used to conduct 
the assessment with the anticipated reference dose (RfD) of 0.01 mg/kg/
day. The analysis used overall mean field trial values and 
conservatively assumed that 30% of the crops on the proposed label 
would be

[[Page 18918]]

treated with DPX-MP062. The chronic dietary exposure to DPX-MP062 is 
0.000309 mg/kg bw/day, and utilizes 3.1% of the RfD for the overall 
U.S. population. The exposure of the most highly exposed subgroup in 
the population, children age 1-6 years, is 0.000633 mg/kg/day, and 
utilizes 6.3% of the RfD. The table below lists the results of this 
analysis which indicate large margins of safety for each population 
subgroup and very low probability of effects resulting from chronic 
exposure to DPX-MP062.

----------------------------------------------------------------------------------------------------------------
                                                                    Maximum Dietary                             
                           Subgroup                               Exposure (mg/kg/day)             %RfD         
----------------------------------------------------------------------------------------------------------------
U.S. Population...............................................                 0.000309                      3.1
Non-Nursing Infants (<1 year old).............................                 0.000264                      2.6
Children (1-6 years)..........................................                 0.000633                      6.3
Females (13-50 years).........................................                 0.000248                      2.5
----------------------------------------------------------------------------------------------------------------

    ii. Acute dietary exposure. Results of the Tier 3 acute dietary 
exposure analysis show that an adequate margin of safety exists for all 
population subgroups and that no acute effects would result from 
dietary exposure to DPX-MP062. Margins of exposure (MOE) were 
calculated based on an acute NOEL of 2 mg/kg bw/day from the rat 
developmental study. The acute dietary exposure to DPX-MP062 is 
0.002271 mg/kg bw/day, MOE = 881, for the overall U.S. population. The 
exposure of the most highly exposed subgroup in the population, 
children age 1 - 6 years, is 0.004469 mg/kg/day, MOE = 448. The results 
of this analysis are given in the table below. All of the results are 
extremely reassuring because they are based on several very 
conservative assumptions and include exposure from ten crops, which 
collectively comprise a significant portion of the diet. Since the MOEs 
are above 100, the acute dietary safety of DPX-MP062 clearly meets the 
FQPA standard of reasonable certainty of no harm.

----------------------------------------------------------------------------------------------------------------
                                           99<SUP>th Percentile of Exposure          99.9<SUP>th Percentile of Exposure   
                                     ---------------------------------------------------------------------------
              Subgroup                 Exposure (mg/kg/                      Exposure (mg/kg/                   
                                             day)               MOE                day)               MOE       
----------------------------------------------------------------------------------------------------------------
U.S. Population.....................           0.002271                881           0.006846                292
Non-Nursing (<1 yr.)................           0.002339                855           0.003937                508
Children (1-6)......................           0.004469                448           0.014810                135
Females (13-50 yrs.)................           0.001893               1057           0.005775                346
----------------------------------------------------------------------------------------------------------------

    3. Drinking water. DPX-MP062 is highly unlikely to contaminate 
groundwater resources due to its immobility in soil, low water 
solubility, high soil sorption, moderate soil half-life, and resulting 
low groundwater ubiquity score (GUS) of 0.620. Both acute and chronic 
drinking water exposure analyses were calculated using EPA screening 
models (SCI-GROW for groundwater and GENEEC for surface water). The 
calculated acute margin of exposure was greater than 5,000 for all 
subpopulations. The predicted chronic exposure for all subpopulations 
was 0.1% of the RfD (0.01 mg/kg/bw/d). Thus exposures to drinking water 
were found to be negligible.
    4. Non-dietary exposure. DPX-MP062 products are not labeled for 
residential non-food uses, thereby eliminating the potential for 
residential exposure. Non-occupational, non-dietary exposure for DPX-
MP062 has not been estimated because the proposed products are limited 
to commercial crop production. Therefore, the potential for non-
occupational exposure is insignificant.

D. Cumulative Effects

     EPA's consideration of a common mechanism of toxicity is not 
necessary at this time because there is no indication that toxic 
effects of DPX-MP062 would be cumulative with those of any other 
chemical compounds. Oxadiazine chemistry is new, and DPX-MP062 has a 
novel mode of action compared to currently registered active 
ingredients.

E. Safety Determination

    1. U.S. population. Dietary and occupational exposure will be the 
major routes of exposure to the U.S. population, and ample margins of 
safety have been demonstrated for both situations. The chronic dietary 
exposure to DPX-MP062 is 0.000309 mg/kg/day, which utilizes 3.1% of the 
RfD for the overall U.S. population, assuming 30% of the crops are 
treated and residues equivalent to overall mean field trial values. The 
MOE for acute dietary exposure to the U.S. population is 881 
(99<SUP>th</SUP> percentile) and 292 (99.9<SUP>th</SUP> percentile). 
Using only PHED data levels A and B (those with a high level of 
confidence), the MOEs for occupational exposure are 5891 for mixer/
loaders and 6511 for applicators. Based on the completeness and 
reliability of the toxicity data and the conservative exposure 
assessments, there is a reasonable certainty that no harm will result 
from the aggregate exposure of residues of DPX-MP062 including all 
anticipated dietary exposure and all other non-occupational exposures.
    2. Infants and children. Chronic dietary exposure of the most 
highly exposed subgroup in the population, children age 1-6 years, is 
0.000633 mg/kg/day or 6.3% of the RfD. For Infants (non-nursing, >1 
yr.), the exposure accounts for 2.6% of the RfD. The MOE for acute 
dietary exposure for children (1-6 years) is 448 (99<SUP>th</SUP> 
percentile) and 135 (99.9<SUP>th</SUP> percentile). For non-nursing 
infants (>1 yr.), the MOE is 855 at the 99<SUP>th</SUP> percentile and 
508 at the 99.9<SUP>th</SUP> percentile. There are no residential uses 
of DPX-MP062 and contamination of drinking water is extremely unlikely. 
Based on the completeness and reliability of the toxicity data, the 
lack of toxicological endpoints of special concern, the lack of any 
indication that children are more sensitive than adults to DPX-MP062, 
and the conservative exposure assessment, there is a reasonable 
certainty that no harm will result to infants and children from the 
aggregate exposure of residues of DPX-MP062, including all anticipated 
dietary exposure and all other non-occupational exposures. Accordingly, 
there is no need to apply an additional safety factor for infants and 
children.

[[Page 18919]]

F. International Tolerances

    To date, no international tolerances exist for DPX-MP062.

[FR Doc. 98-10150 Filed 4-15-98; 8:45 am]
BILLING CODE 6560-50-F