Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

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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
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

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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. Halosulfuronmethyl 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-methyl1H-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 GWN3061 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-methyl1H-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.
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

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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 halosulfuronmethyl.

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-
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

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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 halosulfuronmethyl 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 halosulfuronmethyl 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

N

N

CH3

Cl

N

N N

H

N

H

O

S

O

O

O

CH3

O

CH3

O

O

CH3

N

N

CH3

Cl

NH2

S

O

O

OH

O
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

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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 10-4at 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.
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

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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 GWN3061

(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 postemergence applications.

Artichoke

Application to 

either side of crop 

row, Ground only

1-2 oz 

SANDEA 

or GWN3061

(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 
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

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previously concluded that the residue of concern in plants is the parent compound, halosulfuronmethyl.

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.
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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 cleanup 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 

N

N

O

CH3

O

CH3

N

H

N

N

CH3

Cl

O

O

CH3
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

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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 
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

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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.

LAFT2 HAFT2 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
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

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(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.

LAFT2 HAFT2 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)
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

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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
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

Page 13 of 17

References

DP#s: 173627 & 180565

Subject: PP#2G4073. Temporary Tolerance Petition and Experimental Use Permit for Use 

of MON 12000 (Permit®) 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®) 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®) 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®) 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
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

Page 14 of 17

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
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

Page 15 of 17

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
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

Page 16 of 17

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
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#: 405659

Page 17 of 17

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 Mexico2 Codex3

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]sulfon

yl]-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

Commodity1 Tolerance (ppm) /Maximum Residue Limit (mg/kg)

US Canada Mexico2 Codex3

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.