1 of 13 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C. 20460

OFFICE OF
CHEMICAL SAFETY
AND POLLUTION PREVENTION

MEMORANDUM

Date: October 28, 2011

SUBJECT: Rimsulfuron. Petitions for New Uses and Tolerances on Caneberry and Bushberry. Summary of Analytical Chemistry and Residue Data.

PC Code: 129009 DP Barcode: D385612, D386178

Decision No.: 4427470 and 443815 Registration No.: 352-768

Petition No.: 0E7809 Regulatory Action: Section 3 Registration Risk Assessment Type: NA Case No.: NA

TXR No.: NA CAS No.: 122931-48-0

MRID No .: 48032001, 48032002, 48332001, 48332002 40 CFR: 180.478

FROM: Elizabeth Holman., Chemist Risk Assessment Branch II (RABII) Health Effects Division (HED; 7509P)

THROUGH: Michael A. Doherty, Ph.D., Senior Chemist

Risk Assessment Branch II Health Effects Division (7509P)

Richard A. Loranger, Ph.D., Senior Scientist Risk Assessment Branch II (RABII) Health Effects Division (HED; 7509P)

TO: Kable Davis, RM 25 Herbicide Branch (HB) Registration Division (RD; 7505P)

Sidney Jackson/Barbara Madden, RM 05 Risk Integration, Minor Use, and Emergency Response Branch Registration Division (RD; 7505P)Rimsulfuron Summary of Analytical Chemistry and Residue Data D385612, D386178

2 of 13 I. CONCLUSIONS

Regulatory Recommendations

There are no residue chemistry issues that woul d preclude granting a registration for uses of rimsulfuron (25% water soluble granule (WDG) formulation; DuPontTM Matrix ® SG Herbicide (EPA No. 352-768)) on caneberry and bushberry. HED recommends for the following permanent

tolerances:

Caneberry, subgroup 13-07A ........................................................0.01 ppm Bushberry, subgroup 13-07B ........................................................0.01 ppm

Under a separate submission (DP 386178, Decision No. 443815), the registrant has submitted revised analytical enforcement methods in order to fulfill conditional data requirements previously identified (DP 326655). HED has reviewed these revised methods, which were needed to address problems identified by the independent laboratory validation, and determined that all issues have been addressed. Thus, this conditional data requirement has been met.

In addition, in order to ensure that legal uses of rimsulfuron under FIFRA do not result in illegal residues in food under the FFDCA, HED recommends for the following tolerance expression to be implemented for rimsulfuron under 40 CFR 180.478:

(a) General. Tolerances are established for residues of the herbicide rimsulfuron, including its metabolites and degradates, in or on the commodities in the table below. Compliance with the tolerance levels specified below is to be determined by measuring only rimsulfuron (N -((4,6- dimethoxypyrimidin-2-yl)aminocarbonyl)-3-(ethylsulfonyl)-2-pyridinesulfonamide).

Residue Chemistry Deficiencies

None.

II. ACTION REQUESTED

DuPont has submitted petitions supporting the use of rimsulfuron on caneberry and blueberry (PP# 0E7809). The petitioner is proposing the establishment of the following permanent

tolerances for residues of rimsulfuron:

Caneberry, subgroup 13-07A ........................................................0.01 ppm Bushberry, subgroup 13-07B ........................................................0.01 ppm

III. EXECUTIVE SUMMARY

Tolerances for residues of rimsulfuron [ N -((4,6-dimethoxypyrimidin-2-yl)aminocarbonyl)-3- (ethylsulfonyl)-2-pyridinesulfonamide] are listed in 40 CFR 180.478 and are expressed in terms of rimsulfuron only. Permanent tolerances are established for residues of rimsulfuron at levels ranging from 0.01 ppm in/on various tree fruits, tree nuts and grapes to 0.1 ppm in/on potatoes and field corn commodities [40 CFR §180.478(a)].Rimsulfuron Summary of Analytical Chemistry and Residue Data D385612, D386178

3 of 13 The nature of the residue of rimsulfuron in plants and livestock has been adequately delineated based on metabolism studies conducted with rimsulfuron in field corn, potatoes, tomatoes, lactating goat, and laying hen. The metabolic pathways were found to be similar in plants and livestock. The major route of rimsulfuron metabolism/degradation involves sulfonylurea bridge contraction, with sulfonylurea bridge cleavage as a minor metabolic route. Based on the results of the studies, HED has concluded that the residue of concern in plant and livestock commodities

is rimsulfuron.

An adequate method is available to enforce the established tolerances, a high performance liquid chromatography with ultraviolet (HPLC/UV) detection with column switching. The method, AMR-1241-88, has a limit of quantitation (LOQ) of 0.05 ppm. Subsequently, DuPont proposed two additional methods using liquid chromatography with tandem mass spectroscopy (LC/MS/MS) for tolerance enforcement: Method DuPont-15033 for watery and dry crop matrices, and Method DuPont-15027 for oily crop ma trices. These methods were also adequate for data collection, as shown in the submitted studies. The validated LOQ is 0.010 ppm in each

matrix.

Adequate independent laboratory validation (ILV) data were submitted for both methods. As summarized previously (DP# 326655), these ILV made specific recommendations for revisions

to DuPont Methods 15027 and 15033. Submittal of revised methods was a condition of registration for D326655 and these revisions have now been made. HED has reviewed these revisions, which included correction of typographical errors and the addition of refrigeration/homogenization periods, and determined that they are adequate. Thus, the conditional data requirements have now been met with these submittals.

Adequate field trial data have been submitted for caneberry and blueberry reflecting treatment at 1x the proposed rate. The submitted crop field trial data were collected using the proposed enforcement methods and are supported by adequate storage stability data. Residues of rimsulfuron were <LOQ (<0.01 ppm) in/on all samples of caneberries and blueberries collected at the appropriate preharvest interval (PHI). The data indicate that the proposed tolerances for these berry commodities are adequate.

There are no associated processed commodities with the caneberry and blueberry; therefore, no processing studies were submitted or required for this tolerance petition. There is no impact on the existing tolerances for livestock feedstuffs from these proposed uses and no revisions to these existing tolerances are required.

Although rotational crop issues are not relevant to the proposed uses on berries, adequate confined rotational crop data are available to support minimum plant-back intervals up to 18 months, depending on the end-use product. As the label for rimsulfuron currently specifies minimum plantback intervals compatible with these plantback intervals, data requirements for rotational crops are fulfilled and tolerances are not required for rotational crops.

BackgroundRimsulfuron Summary of Analytical Chemistry and Residue Data D385612, D386178

4 of 13 Rimsulfuron is a sulfonylurea herbicide (Group 2) that works via inhibition of acetolactate synthase (ALS). It is currently registered to E. I. du Pont de Nemours and Co. (DuPont) for use on potatoes, field corn, tomatoes, grapes, soybean, various tree fruits, and tree nuts for pre and post-emergence control of annual grasses, broadleaf weeds, and yellow nutsedge. Permanent tolerances are established for residues of rimsulfuron at levels ranging from 0.01 ppm in/on various tree fruits, tree nuts and grapes to 0.1 ppm in/on potatoes and field corn commodities [40 CFR §180.478(a)]. The chemical structure and nom enclature of rimsulfuron are presented in Table 1. The physicochemical properties of the t echnical grade of rimsulfuron are presented in

Table 2.

Table 1. Rimsulfuron Nomenclature.

Compound

S N

O N H O
N H

O N N OCH 3

OCH 3 SO 2 C 2 H 5

Common name Rimsulfuron

Company experimental name DPX-E9636

IUPAC name 1-(4,6-dimethoxypyrimidin-2-yl)-3-(3-ethylsulfonyl-2-pyridylsulfonyl)urea

CAS name N-[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]-3-(ethylsulfonyl)-2- pyridinesulfonamide

CAS registry number 122931-48-0

End-use product (EP) 25% WDG (Matrix TM SG Herbicide; EPA Reg. No. 352-768)Rimsulfuron Summary of Analytical Chemistry and Residue Data D385612, D386178

5 of 13 Table 2. Physicochemical Propertie s of Technical Grade Rimsulfuron.

Parameter Value Reference

Melting point 172-173  C Reviewed in DP# 193018, M. Nelson, 23/NOV/1993; Also, MRID No. 47572805. All product chemistry requirements reported to be

fulfilled. pH 4.32 to 5.89 (1% dilution in water)

Density 1.5032 ± 0.0016 g/cm 3

Water solubility pH 5: 0.135 ± 0.005 g/L (25°C) pH 7: 7.3 ± 0.03 g/L (25  C) pH 9: 5.56 ± 0.05 g/L (25  C) pH 4-4.5: 0.024 ± 0.001 g/L (20  C)

Solvent solubility (25°C) N,N-dimethylformamide 241 ± 1 g/L Dimethyl sulfoxide 113 ± 3 g/L Methylene chloride 35.5 ± 0.4 g/L Acetonitrile 17.2 ± 0.5 g/L Acetone 14.8 ± 0.5 g/L Ethyl acetate 2.85 ± 0.17 g/L Methanol 1.55 ± 0.11 g/L Toluene 0.363 ± 0.022 g/L Xylene 0.093 ± 0.008 g/L n-Hexane <0.01 g/L

Vapor pressure (25°C) <10 -5 Pa

Dissociation constant, pK

a 4

Octanol/water partition coefficient, Log(K OW ) pH 5: 1.94 pH 7: 0.0342 pH 9: not attempted

UV/visible absorption spectrum pH 1.80 at 230 nm, ε = 1.78 x 10 4 (log ε = 4.25) and at 290 mm, ε = 1.81x 10 2 (log ε = 2.26)

pH 2.10 at 290 nm, ε = 2.03 x10 2 (log ε = 2.31)

pH 5.03 at 240 nm, ε = 2.24 x 10 4 (log ε = 4.35) and at 290 nm, ε = 4.81 x 10 2 (log ε = 2.68)

IV. RESULTS/DISCUSSION

860.1200 Directions for Use

DuPont has submitted a proposed label for a 25% WDG formulation, DuPontTM Matrix ® SG Herbicide (EPA No. 352-768), proposed for use on caneberry (raspberry, blackberry) and blueberry. A summary of the proposed use directions is presented in Table 3.Rimsulfuron Summary of Analytical Chemistry and Residue Data D385612, D386178

6 of 13 Table 3. Summary of Directions for Use of Rimsulfuron.

Applic. Timing Form. Applic.

Rate

lb ai/A Max. No. Applic. per

Season RTI 1
(days) Max. Seasonal Applic. Rate

lb ai/A PHI (days) Use Directions and

Limitations

Caneberry (Raspberry, Blackberry)

Preemergence,
postemergence and/or post harvest 25% WDG 0.03-

0.06 2 -- 0.06 21 Apply using a directed spray application or

broadcast banded application treatment.

Blueberry

Preemergence,
postemergence and/or post harvest 25% WDG 0.03-

0.06 2 -- 0.06 21 Apply using a directed spray application or

broadcast banded application treatment.

1 RTI = Retreatment interval

Conclusions . The label directions are adequate to allow evaluation of the residue data relative to the labeled uses. The available caneberry and blueberry data support the proposed 21-day PHI. It is noted that while all blueberry field tria ls were conducted with an adjuvant (non-ionic surfactant or crop oil concentrate), none of the caneberry trials included an adjuvant. The label directions include no discussion of the use of adjuvant for the proposed commodities. However, HED finds the blueberry data adequate for repres entation of the impact of adjuvants on residue levels in/on berries in general, and therefore no prohibition of the use of adjuvant on caneberry is required. See Section 860.1500 for further discussion.

860.1300 Nature of the Residue - Plants and Livestock

MARC Decision Memo, 11/FEB/1998, L. Cheng, G.J. Herndon; and DP# 200158, M.J. Nelson, 29/MAR/1994 MARC Briefing Memo, 04/FB/1998, L. Cheng; and DP# 200157, M.J. Nelson, 17/MAR/1994

The nature of the residue in plant and livestock commodities is adequately understood based on metabolism studies conducted with rimsulfuron, labeled in the pyridine or pyrimidine ring, in field corn, potatoes, tomatoes, lactating goat, and laying hen.

The metabolic pathways were found to be similar in plants and livestock. The major metabolic route of rimsulfuron metabolism/degradation involves sulfonylurea bridge contraction, withsulfonylurea bridge cleavage as a minor metabolic route. The metabolites detected were IN70941, IN-70942, IN-E9260, IN-J290, IN-69190 (goat) , IN-H1043 (goat), IN-T5831 (potato), IN-JF999 (hen, tomato), and unresolved polar/nonpolar products. Based on the results of the studies, HED has concluded that the residue of concern in plant and livestock commodities is

rimsulfuron.

860.1340 Residue Analytical Methods

Enforcement methods : Currently, an HPLC/UV method exists for the enforcement of tolerancesfor residues of rimsulfuron in/on corn, potato, and tomato commodities. The method, AMR1241-88, involves extraction of samples with pH 7 potassium phosphate buffer and methanol (75:25, v:v). The extract is acidified to pH 2.5-3.5 (using concentrated phosphoric acid) and filtered for analysis by HPLC/UV with column switching, using a phenyl column for clean-upRimsulfuron Summary of Analytical Chemistry and Residue Data D385612, D386178

7 of 13 chromatography followed by an R

x column for analytical chromatography. The LOQ is 0.05

ppm.

DuPont also proposed two additional methods using liquid chromatography with tandem mass spectroscopy (LC/MS/MS) for tolerance enforcement: Method DuPont-15033 for watery and dry crop matrices, and Method DuPont-15027 for oily crop matrices. These methods were also adequate for data collection, as shown in the submitted studies. The validated LOQ is 0.010 ppmin each matrix. Based on feedback from the ILV for each method, revised methods DuPont15033 and DuPont-15027 have been submitted and address all recommended changes from the ILV. These changes included the addition of refrigeration/homogenization periods, in order to reduce the degradation of rimsulfuron residues, and fixing noted typographical errors. Thus, the conditional data requirement from D326655 (D. Rate, 5/13/2007) has been met.

Data-Collection methods: Samples were analyzed for rimsulfuron using the LC/MS/MS method, DuPont-15033 (Revision 1), as described above and in D326655.

Conclusions. The submitted LC/MS/MS methods (Method 15033 and 15027, Revision 1) are adequate for enforcing tolerances. No new DER was written for the submitted revised methods (MRIDs 48332001 and 48332002), as it has been reviewed in a previously submitted petition (DP# 326655, D. Rate, 5/13/2007). The current submission incorporates the ILV comments as previously requested by HED and fulfills the conditional data requirement set in D326655. The methods do not require validation by EPA’s Fort Meade laboratory, and can be forwarded to

FDA.

860.1360 Multiresidue Methods

DP#s 184551 etc., M. Nelson, 25/FEB/1994

Rimsulfuron is not recovered by FDA Multiresi due Methods. The multiresidue method test

results have been forwarded to FDA.

860.1380 Storage Stability

Adequate storage stability data were submitted concurrently with crop field trial data for rimsulfuron in/on caneberry and blueberry (MRIDs 48302001 and 48302002). To support the sample storage intervals, a concurrent storage stability study was conducted using control samples of caneberry and blueberry fortified with rimsulfuron at 0.10 ppm. These samples were stored frozen (~ -20 oC) and analyzed at 706 days (caneberry) or 379 days (blueberry) with a freshly fortified sample. The data indicate that residues of rimsulfuron are stable for up to 23 months in/on caneberry and for up to 12.5 months in/on blueberry stored at ~-20  C.

The storage intervals and conditions of samples from the crop field trials submitted to support this petition are presented in Table 4.

TABLE 4 Summary of Storage Conditions and Int ervals of Samples from Crop Field TrialsRimsulfuron Summary of Analytical Chemistry and Residue Data D385612, D386178

8 of 13 Matrix Storage Temperature 1
(°C) Actual Storage Duration Interval of Demonstrated Storage Stability 2

Caneberry (blackberry and raspberry), mature fruit ~ -20 646-680 days (21-22 months) Concurrent storage stability data

indicate that residues of rimsulfuron

are stable in/on caneberries stored frozen for up to 706 days (23 months).

Blueberry fruit

~ -20 320-355 days (10.5-11.7 months) Concurrent storage stability data

indicate that residues of rimsulfuron

are stable in/on blueberries stored

frozen for up to 379 days (12.5 months).

1 Storage duration from harvest to analysis; caneberry samples we re extracted and analyzed on the same day, blueberry samples were analyzed 0-1 days after extraction.

Conclusions . The submitted concurrent storage stability study is adequate and indicates that residues of rimsulfuron are stable for up to 23 months in/on caneberry and up to 12.5 months in/on blueberry. Although, no 0-day data were pr ovided with the concurrent storage stability study, these data are adequate to support the storage conditions and durations of samples from the subject field trials.

Field trial samples of caneberry and blueberry commodities were stored frozen from collection to analysis and were analyzed within 22 months (caneberry) or 12 months (blueberry) of collection. Therefore, the submitted concurrent storage stability data provides adequate coverage of the time periods during which samples were stored frozen.

860.1400 Water, Fish, and Irrigated Crops

There are no proposed or registered uses that are relevant to this guideline topic.

860.1460 Food Handling

There are no proposed or registered uses that are relevant to this guideline topic.

860.1480 Meat, Milk, Poultry, and Eggs

The proposed uses will have no impact on livestock commodities, as there are no associated livestock feed commodities from caneberry or blueberry. Therefore, the livestock dietary burden analysis and livestock tolerances remain unchanged since the most recent petition with associated livestock commodities (DP# 360852, D. Rate, Aug 2009).

860.1500 Crop Field Trials

48302001.der.doc (Caneberry), E. Holman, Aug 2011 48032002.der.doc (Blueberry), E. Holman, Aug 2011

DuPont submitted field trial data supporting the use of rimsulfuron (25% WDG) on caneberry and blueberry as a single or split postemergence application totaling 0.06 lb ai/A. The results from these field trials are discussed below, and the residue data are summarized in Table 5.Rimsulfuron Summary of Analytical Chemistry and Residue Data D385612, D386178

9 of 13 TABLE 5. Summary of Residue Data from Crop Field Trials with Rimsulfuron.

Commodity Total Applic.
Rate,

lb ai/A PHI (days) Analyte Residue Levels 1
(ppm)

N Min. Max. HAFT 2 Median Mean Std. Dev. 3

Caneberry subgroup 0.0641-

0.0674 21-24 Rimsulfuron 12 <0.01 <0.01 <0.01 <0.01 <0.01 NA

Blueberry 0.0604-

0.0660 19-23 Rimsulfuron 16 <0.01 <0.01 <0.01 <0.01 <0.01 NA

1 All residues in caneberry sa mples were <LLMV (<0.01 ppm).

2 HAFT = Highest Average Field Trial.

3 NA = not applicable. All residues were <LLMV.

Caneberry The Interregional Research Project No. 4 (IR-4) has submitted field trial data for rimsulfuron on caneberry. Six caneberry field trials (2 blackberry and 4 raspberry) were conducted in Zones 2 (NJ; 1 trial), 5 (MI; 1 tria l), 10 (CA; 1 trial) and 12 (OR; 3 trials) during the 2007 growing season.

Each test site included one control and one tr eated plot. Treated plots received a single soil application of a 25% water dispersible granule (WG) formulation of rimsulfuron at a target rate of 0.0625 lb ai/A. The treatment was applied to the ground next to the base of the plants in a swath at least 36 inches wide on either side of the rows. The application was not concentrated into the swath. This is described as a broadcast application in the protocol, while some of the field trials describe it as a banded application. Both terms are used in the study report, and all trial sites performed the application correctly as intended by the protocol. Applications were made in spray volumes of 21-37 gal/A using a CO 2 backpack sprayer. A spray adjuvant was not used for any of the trials. Mature raspberries and blackberries were harvested from test sites at pre-harvest intervals (PHIs) of 21-24 days.

Samples were analyzed for residues of rimsulfuron using high performance liquid chromatography with tandem mass spectrometry. The procedure used for analysis of rimsulfuron was derived from DuPont method #15033. The validated limit of quantitation (LOQ) was determined to be 0.00848 ppm and the limit of detection (LOD) was determined to be 0.00283 ppm. The lower limit of method validation (LLMV) was 0.010 ppm. The method was adequate for data collection based on acceptable method validation and concurrent method

recoveries.

Samples were stored frozen (~ -20oC) from ha rvest to analysis for 646-680 days (21-22 months); samples were extracted and analyzed on the same day. Storage stability data were generated concurrently with the field trial study demonstra ting that residues of rimsulfuron were stable in/on fortified samples of caneberry stored frozen for up to 706 days (23 months). Although no 0-day data were provided with the concurrent storage stability study, these data are adequate to support the storage conditions and durations of samples from the subject field trials.

Residues of rimsulfuron were <0.01 ppm in/on caneberry harvested 21-24 days following a single application of the 25% WG formul ation of rimsulfuron at 0.0641-0.0674 lb ai/A.

No residue decline data were included in the study.Rimsulfuron Summary of Analytical Chemistry and Residue Data D385612, D386178

10 of 13 Blueberry The Interregional Research Project No. 4 (IR-4) has submitted field trial data for rimsulfuron on blueberry. Eight field trials were conducted in Zones 1 (ME; 1 trial), 2 (NC; 3 trials), 5 (MI; 3 trials) and 12 (OR; 1 trial) during the 2008 growing season.

Each test site included one control and one tr eated plot. Treated plots received a single soil application of a 25% water dispersible granule (WG) formulation of rimsulfuron at a target rate of 0.0625 lb ai/A. Banded applications to the ground on either side of the rows were made in spray volumes of 19.6-35.5 gal/A using a CO 2 backpack sprayer. A non-ionic surfactant (NIS) or crop oil concentrate (COC) was used with the applications at all trial sites. Blueberry fruit was harvested at pre-harvest intervals (PHIs) of 19-23 days.

Samples were analyzed for residues of rimsulfuron using high performance liquid chromatography with tandem mass spectrometry. The procedure used for analysis of

rimsulfuron was derived from DuPont me thod #15033. The limit of quantitation (LOQ) was determined to be 0.0102 ppm; the limit of detection (LOD) was determined to be 0.0034 ppm. The lower limit of method validation (LLMV) was 0.010 ppm. It is noted that the LLMV is lower than the LOQ, but this is not considered to be an issue for the following reasons. The LOQ is an estimated value whereas the LLMV is empirically derived and the difference between them is minor (~0.0002 ppm). The method was adequate for data collection based on acceptable

method validation and concurrent method recoveries.

Samples were stored frozen (~ -20oC) from harvest to analysis for 320-355 days (10.5-11.7 months); samples were extracted 0-1 days before analysis. Storage stability data were generated concurrently with the field trial study demonstra ting that residues of rimsulfuron were stable in/on fortified samples of blueberry stored frozen for up to 379 days (12.5 months). Although, no 0-day data were provided with the concurrent storage stability study, these data are adequate to support the storage conditions and durations of samples from the subject field trials.

Residues of rimsulfuron were <0.01 ppm (<LLM V) in/on blueberry harvested 19-23 days following a single application of the 25% WC G formulation of rimsulfuron at 0.0604-0.0660 lb

ai/A.

No residue decline data were included in the study.

Conclusions. The available caneberry and blueberry field trial data are acceptable and support the proposed use patterns for rimsulfuron (WDG) on these proposed commodities. A single application was used for the submitted field trials whereas the proposed use pattern may include a split application. Given that all residues were <LOQ based on a single application and we would expect residues to be lower with a split application, these field trial data do support a split application use pattern. An adequate number of tests were conducted on each crop in the appropriate geographical regions. All samples were analyzed for the residue of concern using an adequate method, and sample storage conditions and intervals were supported by the available storage stability data.

It is noted that while all of the blueberry trials included an adjuvant in the spray mixture (NIS or COC), none of the caneberry trials included adjuva nts. Given that the blueberry trials, including adjuvant, yielded residues <0.01 ppm (LOQ), identical to the result of the caneberry trials without adjuvant, the impact of adjuvants is believed to be minimal. This would be consistentRimsulfuron Summary of Analytical Chemistry and Residue Data D385612, D386178

11 of 13 with the application being directed to the ground as opposed to the foliage and fruit of the crop. Therefore, while the proposed label does not include discussion of the use of adjuvants on the proposed commodities, HED does not believe that prohibition of the use of adjuvants on caneberry is necessary. The proposed use pattern and label is adequate and revisions are not required.

The field trial data support the proposed 21-day PHI for caneberry and blueberry commodities. The data support tolerances of 0.01 ppm in/on caneberry and blueberry.

860.1520 Processed Food and Feed

There are no processed commodities associated with the proposed commodities of caneberry and blueberry for which residues are expected to concentrate.

860.1650 Submittal of Analytical Reference Standards

An analytical reference standard for rimsulfur on (expires 04/APR/2014) is currently available at the EPA National Pesticide Standards Repository (personal communication with Dallas Wright, ACB, 03/AUG/2011).

860.1850/860.1900 Confined and Field Accumulation in Rotational Crops

DP# 206712, M. Nelson, 24/AUG/1994

Adequate confined rotational crop data are available to support minimum plant-back intervals up to 18 months, depending on the end-use product. As the label for rimsulfuron currently specifies minimum plantback intervals compatible with these plantback intervals, data requirements for rotational crops are fulfilled and tolerances are not required for rotational crops.

860.1550 Proposed Tolerances

Tolerances for residues of rimsulfuron are currently expressed in terms of rimsulfuron

. Permanent tolerances are established for residues of rimsulfuron at 0.01 ppm in/on grapes, pome fruits, stone fruits, citrus fruits, tree nuts and pistachios, 0.05 ppm in/on tomatoes, 0.09 ppm in/on almond hulls, and 0.1 ppm in/on potatoes and field corn grain, forage and stover [40 CFR §180.478(a)]. No tolerances are established for residues in either animal commodities or rotational crops. The proposed and recommended tolerances are presented in Table 6.

As residues were <LOQ in/on all samples of caneberry and blueberry collected at the appropriate PHI, the recommended tolerance is 0.01 ppm.

There are no established or proposed Codex maximum residue limits (MRLs) for residues of rimsulfuron on caneberry (Appendix II) or blueberr y. However, there is a Canadian MRL of 0.05 ppm for rimsulfuron residues on blueberry, based on their method LOQ of 0.05 ppm and no residues above LOQ being observed in their reviewed field trials. Given the availability of a more sensitive analytical method with an LOQ of 0.01 ppm, HED recommends proceeding with setting a tolerance for blueberry of 0.01 ppm.Rimsulfuron Summary of Analytical Chemistry and Residue Data D385612, D386178

12 of 13 Table 8. Tolerance Summary for Rimsulfuron.

Commodity Proposed Tolerance (ppm) Recommended Tolerance (ppm) Comments; Correct Commodity Definition

Caneberry, subgroup 13-07A 0.01 0.01

Bushberry, subgroup 13-07B 0.01 0.01

V. REFERENCES

PP#1F4005. Rimsulfuron in/on Field Corn and Pota toes. Review of Crop Rotation Restrictions on Proposed Labels, DP# 206712, M. Nelson, 24/AUG/1994.

PP#1F4005/EPA Reg. No. 000352LLL. DPX-E9636 tec hnical. Review of Product Chemistry Data Submitted in Support of Registration of New Chemical Herbicide (Rimsulfuron), DP# 193018, M. Nelson, 23/NOV/1994.

HED Metabolism Committee Meeting of 3/23/94. Riinsulfuron (E9636; DPX—E9636), DP# 200158, M.. Nelson, 29/MAR/1994.

PP#1F4005. RIMSULFURON (E9636; DPX—E9636). Briefing for the MED Metabolism Committee Meeting of 3/23/94. DP# 200157, M. Nelson, 17/MAR/1994.

PP# 1F4005. Rimsulfuron in/on Corn and Potatoes. Petition f or First Permanent Tolerances. DP# 184551, M. Nelson, 25/FEB/1994.

ID# 352—555. DuPont Rimsulfuron Technical. ID# 352—556. DuPont Matrix® Herbicide. ID# 352—571. DuPont Basis® Herbicide. Letter of 2/14/95 With Storage Stability Data. DP# 212624, M. Nelson, 05/APR/1995.

Attachments: Appendix I -International Residue Limit Status sheetRimsulfuron Summary of Analytical Chemistry and Residue Data D385612, D386178

13 of 13 Appendix I - International Residue Limit Status

Rimsulfuron (PC Code 129009; July 28, 2011) Summary of US and International Tole rances and Maximum Residue Limits Residue Definition : Rimsulfuron

US Canada Mexico 2 Codex 3

40 CFR 180.478: Plant/Livestock: rimsulfuron, N-((4,6- dimethoxypyrimidin-2- yl)aminocarbonyl)-3-(ethylsulfonyl)- 2-pyridinesulfonamide) N-[[(4,6-dimethoxy-2- pyrimidinyl)amino]carbo nyl]-3- (ethylsulfonyl)-2- pyridinesulfonamide None

Commodity 1 Tolerance (ppm) /Maximum Residue Limit (mg/kg)

US Canada Mexico 2 Codex 3
Caneberry, subgroup 13-07A 0.01 Bushberry, subgroup 13-07B 0.01 0.05 blueberries

Completed: M. Negussie; 08/01/2011

1 Includes only commodities of interest for this action. Tolerance values should be the HED recommendations and not those proposed by the applicant.

2 Mexico adopts US tolerances and/or Codex MRLs for its export purposes.

3 * = absent at the limit of quantitation; Po = postharvest treatment, such as treatment of stored grains. PoP = processed postharvest treated commodity, such as processing of treated stored wheat. (fat) = to be measured on the fat portion of the sample. MRLs indicated as proposed have not been finalized by the CCPR and the CAC.