

                                       
                    UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
                               WASHINGTON, D.C.  20460
                                       
	OFFICE OF CHEMICAL SAFETY
	AND POLLUTION PREVENTION
                                                                               
MEMORANDUM

Date:              26 November 2012

SUBJECT:	Halosulfuron-methyl.  Section 3 Registration on Artichoke, and Caneberry Subgroup 13-07A.  Summary of Analytical Chemistry and Residue Data.

PC Code:  128721
      DP Barcode: D405659
Decision No.:  465913
      Registration No.:  81880-18, 81880-2
Petition No.:  2E8050
      Regulatory Action:  Section 3 Registration
Risk Assessment Type:  NA
      Case No.:  NA
TXR No.:  NA
      CAS No.:  100784-20-1
MRID No.:  See MRID Summary Table 
      40 CFR:  180.479
	

FROM:	Leung Cheng, Chemist
		Risk Assessment Branch III (RAB3)
		Health Effects Division (7509P)

THROUGH:	Jeff Dawson, Acting Branch Chief
		RAB3/HED (7509P)		
		
TO:		Barbara Madden/Sydney Jackson (RM Team 03)
		Risk Integration Minor Use, and Emergency Response Branch
		Registration Division (7505P)




MRID Summary Table
MRID No.
Study Type
Comments
48856701
860.1500 Artichoke
New DER 48856701.der
48856702
860.1500 Caneberry
New DER 48856702.der


Executive Summary

Halosulfuron-methyl is a selective herbicide belonging to the sulfonylurea group of herbicides, which inhibits the action of acetolacetate synthase, a specific plant enzyme.  Halosulfuron-methyl is used for the pre- and postemergence control of annual broadleaf weeds and nutsedges in selected crops, as well as residential turf grass and ornamentals, and is formulated as a dry flowable/water-dispersible granule formulation.    

The Interregional Research Project No. 4 (IR-4), State Agricultural Experiment Station, Rutgers, The State University of New Jersey, Princeton, New Jersey, on behalf of the IR-4 Project and the Agricultural Experimental Stations of California (for artichoke) and California, Georgia, Oregon, Kentucky, and North Carolina (for caneberry) submitted this petition (PP#2E8050) and requested the submission be reviewed under the Pesticide Registration Improvement Act. IR-4 also requested that the establishment of a tolerance for residues of the herbicide halosulfuron-methyl, methyl 3-chloro-5-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]-1-methyl-1H-pyrazole-4-carboxylate, in/on the following raw agricultural commodities:

            Artichoke 	0.05 ppm
            Caneberry subgroup 13-07A	0.05 ppm

The petitioner proposed to amend SANDEA herbicide (EPA Reg. No. 81880-18) and GWN-3061 herbicide (EPA Reg. No. 81880-2) to add uses on artichoke and caneberry. Foliar applications are proposed at a maximum application rate of 0.094 lb active ingredient (ai)/A. A 5-day or 14-day preharvest interval is proposed for artichoke and caneberry subgroup 13-07A, respectively. 

Permanent tolerances are established under §180.479(a)(1) for residues of halosulfuron-methyl, methyl 3-chloro-5-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]-1-methyl-1H-pyrazole-4-carboxylate, including its metabolites and degradates, in or on the meat byproducts of cattle, goat, hog, horse, and sheep at 0.1 ppm. Compliance with the tolerance levels specified is to be determined by measuring only those halosulfuron-methyl residues containing the 3-chlorosulfonamide (3-CSA) moiety, expressed as the stoichiometric equivalent of halosulfuron-methyl.

Tolerances are established under §180.479(a)(2) for residues of halosulfuron-methyl, including its metabolites and degradates, in/on a variety of field, fruit, and vegetable crop commodities, at levels ranging from 0.05 to 2.0 ppm. Compliance with the tolerance levels specified is to be determined by measuring only halosulfuron-methyl.

The nature of the residue in plants has been adequately delineated based on acceptable metabolism studies with corn, sugarcane, and soybean treated both pre- and postemergence.  HED has concluded that the residue of concern in plants is halosulfuron-methyl.

The nature of the residue in livestock has been adequately delineated based on metabolism studies with goats and hens.  HED has concluded that the residue of concern in ruminants is halosulfuron-methyl.  HED previously concluded that tolerances for halosulfuron-methyl residues in poultry commodities were not required due to low use rates, low residues of halosulfuron-methyl in poultry feedstuffs, and the low transfer rate of residues to poultry tissues.

Adequate analytical methods (gas chromatography) are available for the enforcement of tolerances for residues of halosulfuron-methyl in plants (Method RES-109-97-4), and for residues of halosulfuron-methyl and its 3-CSA metabolites in livestock commodities (Method RES-046-93).  The plant method determines halosulfuron-methyl as its rearrangement ester (RRE), and the livestock method converts residues of halosulfuron-methyl and metabolites containing the 3-CSA moiety to 3-CSA for determination.  Samples from the submitted artichoke and caneberry studies were analyzed for residues of halosulfuron-methyl using a modified version of the plant enforcement method.  A Biological and Economic Analysis Division (BEAD/EPA) method validation for Method RES-109-97-4 (MRID 44495801) in rice straw, sugar cane, milo grain, field corn grain, cotton gin byproducts, and almond nutmeats indicated a quantitation limit of 0.05 ppm (DP#250584, G. Jeffrey Herndon, 10/28/98).
 
Residues of halosulfuron-methyl and 3-CSA are not adequately recovered by FDA Multiresidue Method protocols.

Adequate concurrent storage stability data are available for halosulfuron-methyl to support the storage conditions and intervals of artichoke and caneberry samples collected from the field trials. 

There are no livestock feedstuffs associated with the proposed use on artichoke and caneberry, and the livestock dietary burden is not altered. Therefore, no changes to the existing livestock commodity tolerances are needed.  

Adequate confined and limited field rotational crop data are available. HED previously concluded that rotational crop tolerances and restrictions are not required for halosulfuron-methyl.

There are no Codex or Canadian maximum residue limits (MRLs) established for residues of halosulfuron-methyl in/on artichoke and caneberry.  

Regulatory Recommendations and Residue Chemistry Deficiencies

HED has examined the residue chemistry database for halosulfuron-methyl.  Pending submission of a reference standard for the RRE of halosulfuron-methyl (see requirements under Submittal of Analytical Reference Standards), there are no residue chemistry issues that would preclude granting a Section 3 registration for the requested uses on artichoke and caneberry, or the establishment of a tolerance for residues of the halosulfuron-methyl, methyl 3-chloro-5-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]-amino]sulfonyl]-1-methyl-1H-pyrazole-4-carboxylate, including its metabolites and degradates, in/on the commodities below. Compliance with the tolerance levels specified is to be determined by measuring only halosulfuron-methyl.

            Artichoke 	0.05 ppm
            Caneberry subgroup 13-07A	0.05 ppm

A human health risk assessment is forthcoming.

Note to RD  -  the tolerance expression under 40 CFR §180.479 (a)(2) should be revised to the following: "residues of the herbicide halosulfuron-methyl, methyl 3-chloro-5-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]-1-methyl-1H-pyrazole-4-carboxylate, including its metabolites and degradates, in or on the commodities in the following table."

860.1650 Submittal of Analytical Reference Standards

   * An analytical reference standard for the rearrangement ester (RRE) of halosulfuron-methyl must be submitted to the EPA National Pesticide Standards Repository.  

Background

The chemical structure and nomenclature of halosulfuron-methyl and the 3-CSA moiety are presented in Table 1.  The physicochemical properties of the technical grade of halosulfuron-methyl are presented in Table 2.  

Table 1.	Test Compound Nomenclature.
Chemical structure
                                       
Common name
Halosulfuron-methyl
Company experimental name
MON 12000, NC-319
IUPAC name
Methyl 3-chloro-5-(4,6-dimethoxypyrimidin-2-ylcarbamoylsulfamoyl)-1-methylpyrazole-4-carboxylate
CAS name
Methyl 3-chloro-5-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]-1-methyl-1H-pyrazole-4-carboxylate
CAS registry number
100784-20-1
End-use product (EP)
75% dry flowable SANDEA Herbicide; EPA Reg. No. 81880-18) and 75% WG (GWN-3061 Herbicide; EPA Reg. No. 81880-2)
Chemical structure of
3-chlorosulfonamide moiety (3-CSA)
                                       
          3-Chloro-1-methyl-5-sulfamoyl-1H-pyrazole-4-carboxylic acid

Table 2.	Physicochemical Properties of Halosulfuron-methyl.
Parameter
Value
Reference
Melting point/range
175.5-177.2 ºC
MRID 42139403; DP#s 173627 & 180565, 7/30/92, G.J. Herndon
pH
4.11 at 25 ºC (1% w/v slurry)

Density
1.618 g/mL at 25 ºC

Water solubility at 20 ºC
pH 5	0.0015 g/100 mL
pH 7	0.165 g/100 mL
pH 9	0.747 g/100 mL

Solvent solubility at 20 ºC
methanol	0.1616 g/100 mL
n-hexane	0.001278 g/100 mL

Vapor pressure
<1 x 10[-7] mm Hg at 25 ºC

Dissociation constant, Ka
3.61 x 10[-4] at 22.4 ºC

Octanol/water partition coefficient, Log(KOW) at 23 ºC
1.67 at pH 5
-0.0186 at pH 7
-0.542 at pH 9

UV/visible absorption spectrum
Not available


860.1200 Directions for Use

Copies of undated labels were provided for a 75% formulation of halosulfuron-methyl (SANDEA herbicide, EPA Reg. No. 81880-18; GWN-3061 herbicide, EPA Reg. No. 81880-2) with uses on artichoke and caneberry. Subsequently, RD transmitted amended Section B (dated November 12, 2012) for caneberry subgroup 13-07A and a revised SANDEA label. The proposed use directions from the SANDEA and GWN-3061 label are summarized in Table 3. According to the SANDEA label, it is a dry flowable formulation; no specification is available on the GWN label. However, the two proposed label use rates on artichoke and caneberry are identical.


Table 3.	Summary of Directions for Use of Halosulfuron-Methyl.
                               Applic. Timing, 
                               Type, and Equip.
                                 Applic. Rate 
                                   (lb ai/A)
                                   Max. No.
                                  Applic. per
                                    Season
                                 Max. Seasonal
                                 Applic. Rate
                                   (lb ai/A)
                                   PHI (day)
                        Use Directions and Limitations
Caneberry subgroup 13-07A including: blackberry, loganberry, raspberry, black and red, wild raspberry, cultivars, varieties, and/or hybrids of these
Application to either side of crop row, Ground
                        0.5-1 oz (East of the Rockies)
              0.75-2 oz (West of the Rockies) SANDEA or GWN-3061
                                 (0.024-0.094)
                                       2
                                     2 oz
                                    (0.094)
                                      15
Apply a single or sequential application with an interval of 45 days (0.024-0.094 lb ai/A) uniformly with ground equipment in a minimum of 15 gals of water per acre to the ground on either side of the row. Do not apply less than 15 days before harvest. Do not apply if excessive weed growth prevents herbicide contact with ground. Use a non-ionic surfactant with post-emergence applications.
                                   Artichoke
Application to either side of crop row, Ground only
                           1-2 oz SANDEA or GWN-3061
                                 (0.047-0.094)
                                 Not specified
                                     2 oz
                                    (0.094)
                                       5
Apply at 0.047-0.094 lb ai/A uniformly with ground equipment in a minimum of 15 gals of water per acre to the ground on either side of the row and avoiding crop foliage. Do not apply less than 5 days before harvest. Do not apply by air. Use a non-ionic surfactant with post-emergence applications.


Conclusions.  The proposed use directions for the 75% WG formulations are adequate.

860.1300 Nature of the Residue - Plants

Residue Chemistry Memo DP# 251007, 12/10/98, M. Doherty (PP#8F4937)
Residue Chemistry Memo, No DP#, 5/21/96, G.J. Herndon (Metabolism Committee decision)
Residue Chemistry Memo DP# 198361, 7/21/94, G. Otakie (PP#4G4279)
Residue Chemistry Memo DP#s 173627 & 180565, 7/30/92, G.J. Herndon (PP#2G4073)

The nature of the residue in plants is adequately understood based on acceptable metabolism studies with corn, sugarcane, and soybean; all studies investigated pre- and postemergence uses.  The metabolism of halosulfuron-methyl was similar in the three tested crops but dependent on the mode of application (pre- or postemergence).  When halosulfuron-methyl was applied preemergence, initial breakdown of the herbicide in the soil and preferential uptake of the pyrazole moieties resulted in the primary residue being 3-CSA, which has been determined to be less toxic than the parent.  With a postemergence application, the major residue was the parent compound with minimal translocation of the herbicide in the plant, except in grain where the major residue was 3-CSA. 

Based on the very low toxicity of the metabolite 3-CSA, relatively low toxicity of the parent compound, and low residue levels of both parent compound and the 3-CSA metabolite, HED previously concluded that the residue of concern in plants is the parent compound, halosulfuron-methyl.
 
860.1300 Nature of the Residue - Livestock

Residue Chemistry Memo DP# 223801, 11/17/98, M. Doherty (PP#6F4661)
Residue Chemistry Memo, No DP#, 5/21/96, G.J. Herndon (Metabolism Committee decision)
Residue Chemistry Memo DP# 204062, 6/22/94, G.J. Herndon (PP#3F4193)
Residue Chemistry Memo DP# 184435, 1/15/93, G.J. Herndon (PP#2G4073)
Residue Chemistry Memo DP# 181023, 11/12/92, G.J. Herndon 
Residue Chemistry Memo DP#s 173627 & 180565, 7/30/92, G.J. Herndon (PP#2G4073)

Acceptable livestock metabolism studies conducted on goats and hens were previously submitted in conjunction with petitions for uses on corn and sorghum.  In goat milk and tissues, the major extractable residue was the parent; acid hydrolysis released bound or conjugated residues of aminopyrimidine and 3-CSA.

As HED previously concluded, the residue of concern in ruminants is halosulfuron-methyl. However, because the approved enforcement method for livestock commodities quantifies the parent compound and metabolites containing the 3-CSA moiety by converting residues to 3-CSA, tolerances for residues of parent and its metabolites in livestock commodities are determined as 3-CSA, expressed in halosulfuron-methyl equivalents.  

HED previously concluded (PP#2G4073) that tolerances for halosulfuron-methyl residues in poultry commodities were not required due to low use rates, low residues of halosulfuron-methyl in poultry feed items, and the low transfer rate of residues to poultry tissues.  

860.1340 Residue Analytical Methods

Residue Chemistry Memo DP# 250584, 10/28/98, G.J. Herndon (PP#s 6F4620 & 8F4937)
Residue Chemistry Memo DP# 214890, 5/3/95, G.J. Herndon (PP#3F4193)
Residue Chemistry Memo DP# 202131, 10/4/94, G.J. Herndon (PP#3F4193)

Plants

Enforcement method:  An adequate analytical method is available for enforcement of tolerances for halosulfuron-methyl residues in plants.  The gas chromatography (GC) method quantifies halosulfuron-methyl as its RRE (1-H-pyrazole-4-carboxylic acid, 3-chloro-5-[(4,6-dimethoxy-2-pyrimidinyl)amino]-1-methyl, methyl ester) using thermionic-specific detection (TSD, nitrogen specific).  Monsanto Analytical Method RES-109-97-4 (MRID 44495801) has been validated as an enforcement method by the Analytical Chemistry Branch (ACB)/BEAD.  The limit of quantitation on rice straw, sugarcane, milo grain, field corn grain, cotton gin byproducts, and almond nutmeats was estimated to be 0.05 ppm (DP#250584, G. Jeffrey Herndon, 10/28/98). For confirmation, the RRE can be determined by GC/MS with monitoring at m/z 327.
 
                                       
               Rearrangement ester (RRE) of halosulfuron-methyl

Data collection method:  Samples from the artichoke and caneberry studies associated with the subject petition were analyzed for residues of halosulfuron-methyl using the available tolerance enforcement method, Method RES-109-97-4, with modifications.  Briefly, samples were extracted with acetonitrile (ACN)/water, filtered, and partitioned with dichloromethane (DCM).  The DCM extract was evaporated to dryness and redissolved in 15% methanol/DCM for clean-up through a Florisil solid phase extraction (SPE) cartridge.  The eluate was mixed with 0.5 M potassium carbonate to convert halosulfuron-methyl residues to the RRE.  The reaction mixture was then extracted with DCM, and the DCM extract was evaporated to dryness; residues were reconstituted in ethyl acetate for further clean-up through a silica SPE column.  The eluate was evaporated to dryness and redissolved in 50% ethyl acetate/isooctane for analysis by gas chromatography with nitrogen specific detection (GC/NPD).  Residues were expressed in terms of halosulfuron-methyl.  The GC/NPD method was adequate for data collection based on acceptable method validation and concurrent method recoveries. 

Conclusions.  The residue analytical methods data are adequate to satisfy data requirements for the subject action.  Acceptable enforcement methodology is available for tolerance enforcement purposes for residues in/on crop commodities, and residues of halosulfuron-methyl in/on artichoke and caneberry commodities from the crop field trial were determined using an acceptable data collection method.

Livestock

There are no livestock feedstuffs associated with the proposed uses. Therefore, this topic is not relevant.

860.1360 Multiresidue Methods

Residue Chemistry Memo DP# 189198, 3/8/94, G.J. Herndon (PP#3F4193)

Adequate multiresidue method data for halosulfuron-methyl and 3-CSA were submitted previously in conjunction with PP#3F4193.  Residues of halosulfuron-methyl and 3-CSA are not recoverable by the FDA Multiresidue Protocols A through E.  The results have been forwarded to FDA.  

860.1380 Storage Stability

Residue Chemistry Memo DP# 189198, 3/8/94, G.J. Herndon (PP#3F4193)

Adequate storage stability data were previously submitted (DP#243050, M. Doherty, 1/5/99)  indicating that halosulfuron-methyl is stable in corn grain stored frozen for up to 823 days (27 months) and in soybeans, wheat, lettuce, and sugar beets stored frozen for up to 996 days (33 months).  

Samples from the artichoke and caneberry field trials were stored frozen (~-20 ºC) from harvest/processing to analysis for up to 700 days for artichoke and 627 days for caneberry.  Concurrent storage stability data were provided to support the new studies.

Conclusions.  The concurrent storage stability data are adequate to support the new studies.

860.1400 Water, Fish, and Irrigated Crops

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

860.1460 Food Handling

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

860.1480 Meat, Milk, Poultry, and Eggs

There are no livestock feed stuffs associated with the proposed uses. Therefore, this topic is not relevant.

860.1500 Crop Field Trials

Artichoke

DER Reference:  48856701.der.doc

The petitioner has submitted field trial data on artichoke.  Three field trials were conducted in the United States during the 2009 growing season in the North American Free Trade Agreement (NAFTA) Growing Zone 10 (CA; 3 trials).  

Each trial consisted of one untreated plot and one treated plot.  At each trial location, the treated plots received a single banded application to the ground of a 75% ai formulation (Sandea Herbicide) at 0.093 lb ai/A.  All applications were made using a backpack in spray volumes of 30 gal/A.  An additive (NIS Exit at a concentration of 0.21% v/v) was added to the spray mixture for each of the applications for all trials. 

Samples of artichoke head (bud) were harvested at 5 days after application, i.e., at a preharvest interval (PHI) of 5 days.  Samples were analyzed for residues of halosulfuron-methyl using the method "Analytical Method for the Determination of MON 12000 in Raw Agricultural Commodities and Processed Fractions", RES-109-97-4, December 1997.  The method was validated at 0.05 and 0.5 ppm and, therefore, the LOQ (determined as the lowest level of method validation, LLMV) is 0.05 ppm.  The calculated limit of detection is 0.013 ppm.  

Samples were placed in frozen storage at the field sites within 45 minutes of collection.  All samples were shipped within 60 days of collection by Agricultural Chemicals Development Services, Inc. (ACDS) freezer truck to the USDA-ARS Research Station, Salinas, CA for frozen storage. Samples were maintained frozen (-20 °C) for about 22 months prior to extraction and analysis at USDA-ARS-SAA, Tifton, GA.  

The results of the artichoke field trials are summarized in Table 4.  Following a single foliar broadcast application of the herbicide Sandea at 0.093-0.094 lb ai/A, residues (and per trial averages) of halosulfuron-methyl in/on artichoke heads harvested at 5-day PHIs were all <0.05 ppm.  

TABLE 4.  Summary of Residue Data from Crop Field Trials with Halosulfuron-methyl.
Commodity
                                     Total
                                     Rate
                                    lb ai/A
                                  PHI (days)
                            Residue Levels (ppm)[1]

                                       
                                       
                                       n
                                  Sample Min.
                                  Sample Max.
                                    LAFT[2]
                                    HAFT[2]
                                    Median
                                     Mean
                                  Std.  Dev.
Heads
                                  0.093-0.094
                                       5
                                       3
                                     0.05
                                     0.05
                                     0.05
                                     0.05
                                     0.05
                                     0.05
                                      NA
[1] Except for sample min/max, values reflect per trial averages; n = no.  of field trials.  For calculation of median, mean, and standard deviation, the LOQ (0.05 ppm) was used for any results reported as <LOQ in Table C.3.  N/A = Not applicable.  
[2] LAFT = lowest average field trial; HAFT = highest average field trial.

Conclusions.   The number and locations of the field trials are in accordance with OCSPP 860.1500 for artichoke. The submitted field trial data reflect a single postemergence application directed to the ground at 0.093-0.094 lb ai/A, with artichoke heads harvested at PHIs of 5 days. An acceptable method was used for the quantitation of residues of halosulfuron-methyl, and the study is supported by adequate storage stability data. 

Caneberry

DER Reference:  48856702.der.doc

The petitioner has submitted field trial data on caneberry.  Four raspberry field trials were conducted in the United States and Canada during the 2008 growing season in the North American Free Trade Agreement (NAFTA) Growing Zones 1 (Williamson, NY), 12 (OR; 2 trials), and 5A (Frelighsburg, QC).  Also, four blackberry field trials were conducted in Zones 2 (Jackson Springs, NC), 5 (Lansing, MI), 10 (Kingsbury, CA), and 12 (Aurora, OR).

Each trial consisted of one untreated plot and one treated plot.  At each trial location, the treated plots received a single banded application to the ground on either side of the caneberry row of a 75% ai formulation (Sandea Herbicide) at 0.094 lb ai/A (range of 0.093-0.098 lb ai/A).  All applications were made using a backpack sprayer in spray volumes of 21-36 gal/A.  An additive (NIS Induce at a concentration of 0.25% v/v) was added to the spray mixture for only the NC trial. 

Samples of blackberry and raspberry were harvested at 13-15 days after application, i.e., at a PHI of 13-15 days.  Samples were analyzed for residues of halosulfuron-methyl using the method "Analytical Method for the Determination of MON 12000 in Raw Agricultural Commodities and Processed Fractions", RES-109-97-4, December 1997.  The method was validated at 0.05 and 0.5 ppm and, therefore, the LOQ (determined as the lowest level of method validation, LLMV) is 0.05 ppm.  The calculated limit of detection is 0.016 ppm.  

Samples were placed in frozen storage at the field sites within 3 hours of collection.  All samples were shipped within 60 days of collection by Agricultural Chemicals Development Services, Inc. (ACDS) freezer truck to the USDA-ARS Research Station, Salinas, CA for frozen storage. Samples were maintained frozen (-20 °C) for about 21 months prior to extraction and analysis (within 7 days of extraction) at USDA-ARS-SAA, Tifton, GA.  

The results of the caneberry field trials are summarized in Table 5. Following a single foliar broadcast application of the herbicide Sandea at 0.093-0.094 lb ai/A, residues (and per trial averages) of halosulfuron-methyl in/on caneberry harvested at 13-15 day PHIs were all <0.05 ppm.  

TABLE 5.  Summary of Residue Data from Crop Field Trials with Halosulfuron-methyl.
Commodity
                                     Total
                                     Rate
                                    lb ai/A
                                  PHI (days)
                            Residue Levels (ppm)[1]

                                       
                                       
                                       n
                                  Sample Min.
                                  Sample Max.
                                    LAFT[2]
                                    HAFT[2]
                                    Median
                                     Mean
                                  Std.  Dev.
Berries
                                  0.093-0.098
                                     13-15
                                       3
                                     0.05
                                     0.05
                                     0.05
                                     0.05
                                     0.05
                                     0.05
                                      NA
[1] Except for sample min/max, values reflect per trial averages; n = no.  of field trials.  For calculation of median, mean, and standard deviation, the LOQ (0.05 ppm) was used for any results reported as <LOQ in Table C.3.  N/A = Not applicable.  
[2] LAFT = lowest average field trial; HAFT = highest average field trial.

Conclusions.   The number and locations of the field trials are in accordance with OCSPP 860.1500 for caneberry. The submitted field trial data reflect a single postemergence application directed to the ground at 0.093-0.098 lb ai/A, with caneberry harvested at PHIs of 13-15 days. An acceptable method was used for the quantitation of residues of halosulfuron-methyl, and the study is supported by adequate storage stability data. 

860.1520 Processed Food and Feed

There are no processed commodities associated with the proposed uses. Therefore, this topic is not relevant.

860.1650 Submittal of Analytical Reference Standards

An analytical standard is currently available in the EPA National Pesticide Standards Repository for halosulfuron-methyl (expiration 6/14/13).  HED notes that a standard for the rearrangement ester (RRE) of halosulfuron-methyl is also required in support of the tolerance enforcement method for plant commodities.  Analytical reference standards of the 3-CSA metabolite and the RRE must be supplied and supplies replenished as requested by the Repository.  The reference standards should be sent to the Analytical Chemistry Lab, which is located at Fort Meade, to the attention of Theresa Cole at the following address:

	USEPA
	National Pesticide Standards Repository/Analytical Chemistry Branch/OPP
	701 Mapes Road
	Fort George G. Meade, MD  20755-5350

(Note that the mail will be returned if the extended zip code is not used.)

860.1850 and 860.1900 Confined/Field Accumulation in Rotational Crops

Residue Chemistry Memo DP# 225273, 10/29/98, G.J. Herndon
Residue Chemistry Memo No DP#, 5/21/96, G.J. Herndon (Metabolism Committee decision)
Residue Chemistry Memo DP# 192510, 8/30/93, G. Kramer
Residue Chemistry Memo DP#s 188144 and 188814, 3/11/93, G.J. Herndon ((PP#2G4073)

Acceptable confined rotational and limited field rotational crop studies were previously submitted.  The results of both studies indicate that metabolites containing the pyrazole moiety may accumulate in harvested crops planted at intervals greater than one year.  The confined rotational crop study, conducted at 0.19 lb ai/A, indicated that no measurable residues of halosulfuron-methyl were detected in any rotational crop commodities of wheat, soybean, radish and lettuce at any plantback interval (30, 120, and 360 days after treatment).  The limited field rotational crop study, conducted at 0.22 lb ai/A in a split (preplant + postemergence) application with rotated crops of winter wheat, spring wheat, soybean, sugar beet, and leaf lettuce indicated that no measurable residues of halosulfuron-methyl were detected in any field rotational crop samples, except in one spring wheat forage sample at 0.090 ppm (364-day plantback interval).  

HED previously concluded that the residue of concern in rotational crops is halosulfuron-methyl.  Based on the absence of the parent compound in the confined studies and in the limited field rotational crop studies, with the exception of one forage sample, HED previously concluded that rotational crop tolerances and restrictions are not required for halosulfuron-methyl.  

860.1550 Proposed Tolerances

The petitioner proposed the following tolerance expression on artichoke and caneberry subgroup 13-07A: residues of halosulfuron-methyl, methyl 3-chloro-5-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]-1-methyl-1H-pyrazole-4-carboxylate. 

RD should revise 40 CFR § 180.479 (a) (2) to include the following tolerance expression: "residues of the herbicide halosulfuron-methyl, methyl 3-chloro-5-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]-1-methyl-1H-pyrazole-4-carboxylate, including its metabolites and degradates, in or on the commodities in the following table." The compliance statement is correct.

Because all residue values for artichoke and caneberry are below the LOQ, the Agency's Guidance for Setting Pesticide Tolerances Based on Field Trial Data is not utilized for determining an appropriate tolerance level.

There are no Codex or Canadian MRLs established for residues of halosulfuron-methyl in/on artichoke and caneberry.  

Table 5. 	Tolerance Summary for Halosulfuron-methyl
Commodity
                           Proposed Tolerance (ppm)
                          Recommended Tolerance (ppm)
Comments; Correct Commodity Definition
Artichoke
                                     0.05
                                     0.05

Caneberry subgroup 13-07A
                                     0.05
                                     0.05


References

DP#s:		173627 & 180565
Subject:	PP#2G4073.  Temporary Tolerance Petition and Experimental Use Permit for Use of MON 12000 (Permit[(R)]) on Corn; 000524-EUP-TO.  Evaluation of Analytical Method and Residue Data. 
From:  	G.J. Herndon
To:		J. Miller/D. Kenny and A. Kocialski
Dated:		7/30/92
MRIDs:	42139400-08

DP#s:		181023
Subject:	000524-EUP-TA.  Experimental Use Permit for Use of MON 12000 and MON 13900 Together as MON 12041 (Battalion(R)) on Corn; Evaluation of Analytical Method and Residue Data.  CBTS#:  10295.
From:  	G.J. Herndon
To:		J. Miller/D. Kenny and A. Kocialski
Dated:		11/12/92
MRIDs:	42396202 and 42396203

DP#s:		184435
Subject:	PP#2G4073.  Temporary Tolerance Petition and Experimental Use Permit for Use of MON 12000 (Permit[(R)]) on Corn; 000524-EUP-TO.  Amendment of 7/30/92 Addressing Analytical Method and Residue Data Deficiencies.  CBTS#:  10948. 
From:  	G.J. Herndon
To:		J. Miller/D. Kenny and A. Kocialski
Dated:		1/15/93
MRIDs:	42538400-42538404

DP#s:		188144 & 188814
Subject:	PP#2G4073.  Temporary Tolerance Petition and Experimental Use Permit for Use of MON 12000 (Permit(R)) on Corn; 000524-EUP-TO.  Amendment of 2/10/93 Addressing Analytical Method and Proposed Label Deficiencies.  Impact of the Confined Rotational Crop Study Results (EFGWB) on this EUP Request.   CBTS#: 11374 and 11451.
From:  	G.J. Herndon 
To:	J. Miller/D. Kenny and A. Kocialski
Dated:		3/11/93
MRIDs:	None

DP#:		192510
Subject:	ID# 000524-UAT.  Review of limited field rotational study of MON 12000 [3-chloro-5-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]-sulfonyl]-1-methyl-1H-pyrazole-4-carboxylic acid, methyl ester].  Case 023936.  CBTS# 12079.
From:  	G. Kramer
To:		J. Miller
Dated:		8/30/93
MRIDs:	42812104

DP#s:		189198, 198051, 189189, 189178, 189183 & 189195
Subject:	PP#3F04193.  Permanent Tolerance Request for Use of MON 12000 (Halosulfuron) on Field Corn and Grain Sorghum (Milo).  Evaluation of Analytical Method and Residue Data.
From:  		G.J. Herndon
To:		J. Miller/D. Kenny and A. Kocialski
Dated:		3/8/94
MRIDs:	42661401-07, 43042601-02

DP#:		204062
Subject:	PP#3F04193.   Section 3 Registration and Permanent Tolerance Request for Use of MON 12000 (Halosulfuron) on Field Corn and Grain Sorghum (Milo).  Submission Received 2/24/93 Addressing Deficiencies in the Nature of the Residue in Plants and Animals.  CBTS# 13817, 13861.
From:  		G.J. Herndon
To:		J. Miller/D. Kenny and A. Kocialski
Dated:		6/22/94
MRIDs:	42678001-03

DP#:		198361
Subject:	PP#4G04279 and 524-EUP-74 - EUP and Temporary Tolerance Request for the New Chemical MON 12000 on Sugarcane and Sorghum.  CBTS No. 13092.
From:  		G. Otakie
To:		J. Miller/D. Kenny and A. Kocialski
Dated:		7/21/94
MRIDs:	42991201-02

DP#:		202131
Subject:	PP#3F04193.  Section 3 Registration and Permanent Tolerance Request for Use of MON 12000 (Halosulfuron) on Field Corn and Grain Sorghum (Milo).  Submission Received 3/29/94 Addressing Deficiencies in the Regulatory Enforcement Method for Animal Products and the Proposed Section F.  CBTS# 13568
From:  		G.J. Herndon
To:		J. Miller/D. Kenny and A. Kocialski
Dated:		10/4/94
MRIDs:	43195001 and 43177501

DP#:		214890
Subject:	PP#3F04193.  Halosulfuron (MON 12000) on Animal Commodities.  Results of the Petition Method Validation Request.  CBTS# 15480.
From:  		G.J. Herndon
To:		J. Miller/D. Kenny and J. Smith
Dated:		5/3/95
MRIDs:	43195001

DP#:		None
Subject:	Halosulfuron (MON 12000).  The HED Metabolism Committee Meeting Held on May 20, 1996.
From:  		G.J. Herndon
To:		HED Metabolism Committee
Dated:		5/21/96
MRIDs:	None

DP#:		250584
Subject:	PP#6F4620 and 8F4937.  Halosulfuron-methyl on Various Commodities.  Results of the Petition Method Validation Request for the Proposed Enforcement Method.
From:  		G.J. Herndon
To:		V. Walters/ J. Tompkins
Dated:		10/28/98
MRIDs:	44495801 and 44555901

DP#:		225273
Subject:	Halosulfuron.  Revised Section F Proposing Deletion of Existing Rotational Crop Tolerances.
From:  		G.J. Herndon
To:		V. Walters/ J. Tompkins
Dated:		10/29/98
MRIDs:	None

DP#:		223801
Subject:	PP6F4661.  Section 3 Registration and Request for Permanent Tolerances for Halosulfuron-methyl on Sweet Corn and Popcorn.  Evaluation of Analytical Methods and Residue Data.
From:  		M. Doherty
To:		J. Tompkins/V. Walters
Dated:		11/17/98
MRIDs:	43918501

DP#:		251007
Subject:	PP8F4937.  Request for Permanent Tolerances for Halosulfuron-methyl on Cotton, Rice, Pistachio Nuts, and Tree Nut Crop Group (Crop Group 14 as listed in 40 CFR 180.41).  Evaluation of Metabolism of Halosulfuron-methyl in Soybean.
From:  		M. Doherty
To:		J. Tompkins/V. Walters
Dated:		12/10/98
MRIDs:	44689501

Attachment:  
Appendix 1: International Residue Limit Status sheet

Template Version September 2005

Appendix 1.  International Residue Limits 

               Halosulfuron-methyl (PC Code 128721); 10/31/2012
Table A.1 Summary of US and International Tolerances and Maximum Residue Limits 
Residue Definition:
US
Canada
Mexico[2]
Codex[3]
40 CFR 180.479 (a) (2):
Tolerances are established for residues of the herbicide halosulfuron-methyl, methyl 3-chloro-5-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]-1-methyl-1H-pyrazole-4-carboxylate, including its metabolites and degradates, in the table below. Compliance with the tolerance levels specified in the following table is to be determined by measuring only halosulfuron-methyl.
None

None
Commodity[1]
Tolerance (ppm) /Maximum Residue Limit (mg/kg)

                                      US
Canada
Mexico[2]
Codex[3]
Artichoke 
                                     0.05
                                       
                                       
                                       
Caneberry subgroup 13-07A
                                     0.05
                                       
                                       
                                       

                                       
                                       
                                       
                                       

                                       
                                       
                                       
                                       

                                       
                                       
                                       
                                       

                                       
                                       
                                       
                                       

                                       
                                       
                                       
                                       

                                       
                                       
                                       
                                       
Completed:  L. Cheng; 11/21/2012
[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.


