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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C. 20460

OFFICE OF PREVENTION, PESTICIDE

AND TOXIC SUBSTANCES

MEMORANDUM

Date: 03/03/2010.

SUBJECT: Halosulfuron-methyl. Application for Section 3 Registration of Sandea® 

Herbicide (EPA Reg. No. 81880-18) and GWN-3061 Herbicide (EPA Reg. No. 

81880-2) to Add New Uses on: Pea and Bean, Succulent Shelled, Subgroup 6B; 

Vegetable, Tuberous and Corm, Subgroup 1C; Rhubarb; Bushberry Subgroup 13-

07B; Pea and Bean, Dried Shelled, Except Soybean, Subgroup 6C; Apple; and 

Okra. Summary of Analytical Chemistry and Residue Data.

PC Code: 128721 DP Barcode: D367058

Decision No.: 414896 Registration Nos.: 81880-18 and 81880-2

Petition No.: 9E7577 Regulatory Action: Section 3 Registration

Risk Assessment Type: NA Case No.: NA

TXR No.: NA CAS No.: 100784-20-1

MRID Nos.: 47772101 through 47772106 40 CFR: §180.479

FROM: Debra Rate, Ph.D., Biologist

Alternative Risk Integration and Assessment (ARIA) Team

Risk Integration, Minor Use and Emergency Response Branch (RIMUERB)

Registration Division (RD; 7505P)

THROUGH: Steve Funk, Senior Scientist

Risk Assessment Branch III (RABIII)

Health Effects Division (HED; 7509P)

TO: Whang Phang, Ph.D., Toxicologist

RABIII/HED (7509P)

Barbara Madden

Minor Use Team

RIMUERB/RD (7505P)

This document was originally prepared under contract by Dynamac Corporation. The document

has been reviewed by ARIA/HED and revised to reflect current Office of Pesticide Programs 

(OPP) policies.
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

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Executive Summary

Halosulfuron-methyl is a selective herbicide belonging to the sulfonylurea group of herbicides. 

Its mode of action includes the inhibition of a specific plant enzyme, acetolacetate synthase. 

Halosulfuron-methyl is registered for the pre- and postemergence control of annual broadleaf 

weeds and nutsedges in selected crops, as well as residential turf grass and ornamentals. 

Halosulfuron-methyl is sold in the U.S. as a dry flowable/water-dispersible granule formulation.

The petitioner, Interregional Research Project No. 4 (IR-4), has proposed new uses of 

halosulfuron-methyl on: apple; bushberry Subgroup 13-07B; okra; succulent-shelled pea and 

bean Subgroup 6B; dried shelled pea and bean, except soybean, Subgroup 6C; rhubarb; and 

tuberous and corm vegetable Subgroup 1C. In conjunction with the requested amended use, IR-4

has submitted a petition, PP#9E7577, to propose the establishment of permanent tolerances 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:

Pea and bean, succulent shelled, Subgroup 6B ...................................0.05 ppm

Vegetable, tuberous and corm, Subgroup 1C ......................................0.05 ppm

Rhubarb ...............................................................................................0.05 ppm

Pea and bean, dried shelled, except soybean, Subgroup 6C ................0.05 ppm

Apple ...................................................................................................0.05 ppm

Okra .....................................................................................................0.05 ppm

Bushberry, Subgroup 13-07B ..............................................................0.05 ppm

The end-use products relevant to this registration action are Sandea® Herbicide (EPA Reg. No. 

81880-18) and GWN-3061 Herbicide (EPA Reg. No. 81880-2). Both products are currently

registered to Gowan Company and are classified as water-dispersible granular (WG) 

formulations containing 75% halosulfuron-methyl. The formulations are proposed for broadcast 

soil or foliar applications at maximum seasonal rates of 0.023-0.094 lb ai/A depending on the 

crop. Only ground equipment in ≥15 gal/A of water may be used for applications; certain crops 

require the addition of non-ionic surfactants in the spray mixture for enhanced control. The 

proposed preharvest intervals (PHIs) range from 14 to 60 days. 

Permanent tolerances are established under §180.479(a)(1) for residues of halosulfuron-methyl 

and its metabolites and degradates determined as 3-chloro-1-methyl-5-sulfamoylpyrazole-4-

carboxylic acid, expressed as halosulfuron-methyl equivalent in/on the meat byproducts of cattle, 

goat, hog, horse, and sheep at 0.1 ppm. Tolerances are established under §180.479(a)(2) for 

residues of halosulfuron-methyl in/on a variety of field, fruit, and vegetable crop commodities, at 

levels ranging from 0.05 to 2.0 ppm. A time-limited tolerance for sweet potato established under 

§180.479(b) has expired (expiration data 12/31/2008).

The nature of the residue in plants is adequately understood based on acceptable metabolism 

studies with corn, sugarcane, and soybean treated both pre- and postemergence. The terminal 

residue of concern in plants is halosulfuron-methyl.
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

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The nature of the residue in ruminants is adequately understood based on an acceptable goat 

metabolism study. 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-chlorosulfonamide moiety (3-CSA) by converting 

residues to 3-CSA, tolerances for residues in livestock commodities are expressed in terms of 

halosulfuron-methyl and its metabolites determined as 3-CSA, expressed as halosulfuron-methyl 

equivalents. There are no poultry feedstuffs associated with the recommended tolerances and 

crop uses addressed in this action. Therefore, a discussion of the metabolism of halosulfuronmethyl in poultry and hogs is not germane to this petition.

Adequate analytical methods 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 field trial and processing studies were analyzed 

for residues of halosulfuron-methyl using a modified version of the plant enforcement method

with a petitioner-validated limit of quantitation (LOQ) of 0.05 ppm. 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 an LOQ of 0.05 ppm (DP#250584, G. Jeffrey Herndon, 10/28/1998).

Residues of halosulfuron-methyl and 3-CSA are not adequately recovered by FDA Multiresidue 

Method protocols.

Adequate storage stability data are available to support the storage conditions and durations of 

samples collected from the magnitude of the residue and processing studies on apples, blueberry, 

dry bean seed, succulent pea seed, potato tuber, potato processed commodities, and rhubarb. As 

residues of halosulfuron-methyl were found to be stable in tested crop matrices, storage stability

corrections need not be applied to the recommended tolerances for halosulfuron-methyl residues 

for these commodities.

An adequate dairy cattle feeding study is available. Based on the re-evaluation of the feeding 

study relative to the re-calculated dietary burdens of 0.468 ppm for beef cattle and 0.825 ppm for 

dairy cattle, ARIA concludes that tolerances for residues of halosulfuron-methyl need not be 

established for milk or meat, and fat of cattle, goat, hog, horse, and sheep. The established 

tolerance of 0.1 ppm for the meat byproducts of cattle, goat, hog, horse, and sheep are adequate 

for this registration action. The petitioner should note that if additional uses are proposed in the 

future which would result in an increase in the dietary burdens, ARIA/HED will re-assess the 

adequacy of established animal tolerances. 

Residues of halosulfuron-methyl were below the lowest limit of method validation (LLMV; 

<0.05 ppm) in/on all commodity samples treated with the test formulation according to the 

conditions and parameters used in magnitude of the residue studies. The Agency’s tolerance 

spreadsheet was not used for tolerance assessment.
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

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The submitted field trial data on apples and blueberries (the latter is a representative commodity

of Crop Subgroup 13-07B) did not reflect the use of a nonionic surfactant as recommended on 

the proposed label. The data will support a tolerance of 0.05 ppm for apple. The data will 

support a tolerance of 0.05 ppm for the bushberry Subgroup 13-07B provided the label for 

Sandea® Herbicide is amended to remove the instructions pertaining to the use of a non-ionic 

surfactant. If it is IR-4’s intention to add a nonionic surfactant when Sandea® Herbicide is 

applied to bushberry Subghroup 13-07B, then additional field trial data are required which 

include the use of an adjuvant. In the case of apples, the herbicide is applied to the orchard floor, 

and addition of a surfactant will have no effect on residues on the apples.

No residue data were submitted to support the proposed use on okra. The ChemSAC meeting of 

10/18/2006 has recommended the inclusion of okra in Crop Group 8 (Fruiting Vegetables). The 

ChemSAC has also determined that a separate tolerance for okra should be listed in the 

appropriate section of the CFR entry until the new crop group regulation is published. The 

available field trial data for Fruiting Vegetables will be translated to okra. ARIA recommends a

tolerance of 0.05 ppm for residues of halosulfuron-methyl in/on okra.

The representative crops of Subgroup 6B are two commodities of: (1) any succulent shelled 

cultivar of bean (Phaseolus spp.) or (2) immature soybean seed (Glycine max) or (3) any Vigna

spp. and garden pea (Pisum spp.). The submitted field trial data for succulent peas were 

conducted at exaggerated rates (1.4X or 2.8X), and the collected samples did not reflect the 

proposed 30-day PHI (the earliest PHI tested was 55 days). The available data for succulent 

beans, previously submitted under PP#1E06322 (DP#278587, A. Acierto, 6/15/2002) to support 

the established individual tolerance of 0.05 ppm, also do not reflect the proposed use on 

Subgroup 6B because these data represent foliar application whereas the new proposed use 

pattern is for preemergence soil application. ARIA will not require additional data on succulent 

peas since treatment at 1X will likely result in residues below 0.05 ppm, even when harvested at 

a PHI of 30-days. Also, ARIA will not require additional data on succulent beans since soil 

treatment will likely result in residues below 0.05 ppm. ARIA recommends for the proposed 

tolerance of 0.05 ppm for the Subgroup 6B (Pea and Bean, Succulent Shelled) pending a label 

revision to prohibit applications to legumes grown for livestock feeds because no residue data are 

available for cowpea forage and hay. Concomitant with the establishment of a tolerance for 

Subgroup 6B, the individual tolerance for ‘bean, snap, succulent’ should be revoked.

The representative commodities of Subgroup 6C are any one dried cultivar of bean (Phaseolus

spp.) and any one dried cultivar of pea (Pisum spp.) The submitted residue data for dry beans

reflect a single foliar broadcast application conducted at ~1.6X the proposed application rate per 

crop cycle (or ~0.8X the proposed total application rate per year), the use of a nonionic 

surfactant, and the treated samples were collected approximating the proposed 30-day PHI. 

Additional data for dry beans were submitted under PP#1E06322 (DP#278587, A. Acierto, 

6/15/2002) to support the established individual tolerance of 0.05 ppm. These data represent a 

single application of Permit 75 WG Herbicide at 0.032 lb ai/A made 0 to 6 days after planting 

and an 86- to 113-day PHI. ARIA is unable to recommend for the proposed use and tolerance of 

0.05 ppm for Crop Subgroup 6C (dried shelled bean (except soybean) and pea) because residue 

data on dried pea including the forages and hay of field pea cultivars are required. When 

adequate residue data for dried peas become available, the petitioner may again request a

tolerance for Subgroup 6C.
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

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The submitted field trial data on rhubarb were generated using slightly exaggerated rates of ~2.0-

2.1X. ARIA will not require additional data on rhubarb since treatment at 1X will likely result in 

residues below 0.05 ppm. The available data will support the proposed tolerance of 0.05 ppm for 

rhubarb.

The submitted field trial data on potato, the representative commodity of Crop Subgroup 1C, do 

not fully conform to the OPPTS 860.1500 guideline as only 14 trials were conducted whereas the 

guideline requires a minimum of 16 trials to support a subgroup tolerance. In addition, the potato 

data were generated using exaggerated rates of ~2.0-2.1X. At this exaggerated rate all potato 

residues were <0.05 ppm. Therefore, ARIA will not require additional data on potatoes since 

additional trials at a 1X rate will likely result in residues below 0.05 ppm. The available data 

will support the proposed tolerance of 0.05 ppm for Crop Subgroup 1C.

To fulfill the requirements for an apple processing data, a trial site was treated at ~5.1X the 

proposed maximum seasonal rate to generate samples for processing; however, as residues were 

nondetectable in any apple fruit samples, processing was not initiated. These data are adequate 

to conclude that an additional apple processing study and tolerances for apple processed 

commodities are not required for this action.

The submitted processing data for potato are acceptable. Residues of halosulfuron-methyl were 

nonquantifiable (<0.05 ppm) in/on potato tubers following treatments at 2X the proposed 

seasonal rate. Residues were also nonquantifiable in processed potato granules/flakes, chips, and 

wet peel. The Agency would have preferred that a trial with an exaggerated rate equal to or 

higher than the maximum theoretical concentration factor of 5X for potato have been conducted. 

However, because of phytotoxicity limitations as reported in the magnitude of the residue trials, a 

new potato processing study will not be required. Based on these data, tolerances for potato 

processed commodities are not needed.

Adequate confined and limited field rotational crop data are available. 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.

There are no Codex, Canadian, or Mexican maximum residue limits (MRLs) established for 

residues of halosulfuron-methyl in crop or livestock commodities.
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

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Regulatory Recommendations and Residue Chemistry Deficiencies

ARIA has examined the residue chemistry database for halosulfuron-methyl and evaluated the 

adequacy of study submissions associated with the current action. Pending submission of a 

revised Section B (see requirements under Directions for Use), a revised Section F (see

requirements under crop field trials) and the submission of standards for the 3-CSA (3-

chlorosulfonamide acid) metabolite and the RRE of halosulfuron-methyl (see requirements under 

Submittal of Analytical Reference Standards), there are no residue chemistry data gaps that 

would preclude ARIA from recommending for registration for the following requested crops 

and/or crop subgroups. ARIA recommends for the establishment of tolerances for residues of the 

herbicide halosulfuron-methyl in/on the following raw agricultural commodities and/or crop 

subgroups:

Pea and bean, succulent shelled, Subgroup 6B ...................................0.05 ppm

Vegetable, tuberous and corm, Subgroup 1C ......................................0.05 ppm

Rhubarb ...............................................................................................0.05 ppm

Apple ...................................................................................................0.05 ppm

Okra .....................................................................................................0.05 ppm

Bushberry Subgroup 13-07B ...............................................................0.05 ppm

A human health risk assessment is forthcoming. 

Full unconditional registration for the recommended crop/crop subgroup uses (listed above) will 

be issued following adequate resolution of the data gaps listed below.

860.1200 Directions for Use

● For Crop Subgroup 6B (pea and bean, succulent shelled), the label(s) should be amended 

to prohibit applications to legumes grown for livestock feeds because no residue data are 

available for cowpea forage and hay.

● For Crop Subgroup 13-07B (bushberry), the label(s) should be amended to remove the 

instructions pertaining to the use of a non-ionic surfactant. If it is IR-4’s intention to add 

a nonionic surfactant when Sandea® Herbicide is applied to these crops, then additional 

field trial data are required.

 For Crop Subgroup 6C (dried pea and bean (except soybean)), the labels should be 

amended to remove the use directions for Crop Subgroup 6C. 

860.1500 Crop Field Trials
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● Prior to granting a registration on Crop Subgroup 6C (dried shelled pea and bean (except 

soybean)), data on dried pea including the forages and hay of field pea cultivars are 

required from a minimum of five field trials. The requested field trials should reflect total

application rates of 0.047 lb ai/A per crop cycle or 0.094 lb ai/A per year, a minimum 30-

day PHI, and the incorporation of a non-ionic surfactant in the spray mixture. A revised 

Section F should be submitted removing the request for Crop Subgroup 6C (dried shelled 

pea and bean (except soybean)).

860.1650 Submittal of Analytical Reference Standards

● Analytical reference standards for the 3-CSA (3-chlorosulfonamide acid) metabolite and 

the RRE of halosulfuron-methyl must be submitted to the EPA National Pesticide 

Standards Repository.

Modification to the Tolerance Expression as per HED’s Interim Guidance on Tolerance 

Expressions (S. Knizner, 5/27/2009)

 40 CFR§180.479(a)(1):

 Tolerances are established for residues of halosulfuron-methyl, methyl 5-[(4,6-

dimethoxy-2-pyrimidiny)amino]carbonylaminosulfonyl]-3-chloro-1-methyl-1H-pyrazole-4-

carboxylate, 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 those halosulfuron-methyl residues containing the 3-chlorosulfonamide (3-CSA) moiety, 

expressed as the stoichiometric equivalent of halosulfuron-methyl, in or on the commodity.

 40 CFR§180.479(a)(2):

 Tolerances are established for residues of halosulfuron-methyl, methyl 5-[(4,6-

dimethoxy-2-pyrimidiny)amino]carbonylaminosulfonyl]-3-chloro-1-methyl-1H-pyrazole-4-

carboxylate, 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 halosulfuron-methyl.
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Background

The chemical structures and nomenclatures 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. Halosulfuron-methyl Nomenclature.

Chemical structure

N

N

CH3

Cl

N

N N

H

N

H

O

S

O

O

O

CH3

O

CH3

O

O

CH3

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% WG (SANDEA Herbicide; EPA Reg. No. 81880-18)

75% WG (GWN-3061 Herbicide; EPA Reg. No. 81880-2)

Chemical structure of

3-chlorosulfonamide moiety 

(3-CSA)

N

N

CH3

Cl

NH2

S

O

O

OH

O

3-chloro-1-methyl-5-sulfamoyl-1H-pyrazole-4-carboxylic acid
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

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Table 2. Physicochemical Properties of Halosulfuron-methyl.

Parameter Value Reference

Melting range 175.5-177.2oC MRID 42139403; DP#s 

173627 & 180565, 7/30/92, 

G.J. Herndon

pH 4.11 at 25oC (1% w/v slurry)

Density 1.618 g/mL at 25oC

Water solubility at 20oC pH 5 0.0015 g/100 mL

pH 7 0.165 g/100 mL

pH 9 0.747 g/100 mL

Solvent solubility at 20oC methanol 0.1616 g/100 mL

n-hexane 0.001278 g/100 mL

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

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

Octanol/water partition coefficient, 

Log(KOW) at 23oC

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

The end-use products (EPs) relevant to this registration action are Sandea® Herbicide (EPA Reg. 

No. 81880-18) and GWN-3061 Herbicide (EPA Reg. No. 81880-2). Both products are currently

registered to Gowan Company and are classified as WG formulations containing 75% 

halosulfuron-methyl. IR-4 requests that the product labels of these EPs be amended to include 

the proposed new crop uses. The petitioner is proposing to add the following crops to the 

Sandea® Herbicide label: apple, bushberry Subgroup 13-07B, okra, succulent shelled pea and 

bean Subgroup 6B, dried shelled pea and bean (except soybean) Subgroup 6C, rhubarb, and 

tuberous and corm vegetables Subgroup 1C. The petitioner is also proposing to amend the 

product label for GWN-3061 Herbicide to add uses on dried shell pea and bean (except soybean) 

Subgroup 6C.

The proposed use pattern information is presented in Table 3. Supplemental labels (dated 

4/13/2009) for both EPs were provided, along with a copy of the current accepted master label 

for Sandea® Herbicide, (undated). In addition, a description of the proposed uses corresponding 

to Section B for both EPs was also included in the submission.
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Table 3. Summary of Directions for Use of Halosulfuron-Methyl.

Applic. Timing, 

Type, and 

Equip.

Formulation

[EPA Reg. 

No.]

Applic. 

Rate 

(lb ai/A)

Max. No. 

Applic. per 

Season

Max. Seasonal 

Applic. Rate

(lb ai/A)

PHI

(days)

Use Directions and 

Limitations

Apple; East of the Rocky Mts.

Broadcast to 

orchard floor; 

Ground

(≥15 gal/A)

75% WG

[81880-18]

0.023-

0.047

Not 

specified

(NS)

0.094 14

Single or sequential 

applications may be made 

on each side of the tree 

row. Use of a non-ionic 

surfactant (NIS) is 

recommended. 

Application to trees 

established less than one 

year is prohibited.

Apple; West of the Rocky Mts.

Broadcast to 

orchard floor; 

Ground

(≥15 gal/A)

75% WG

[81880-18]

0.035-

0.094 NS 0.094 14

Single or sequential 

applications may be made 

on each side of the tree 

row. Use of an NIS or a 

penetrating type surfactant 

is recommended. 

Application to trees 

established less than one 

year is prohibited.

Bushberry Subgroup 13-07B

Soil broadcast;

Ground

(≥15 gal/A)

75% WG

[81880-18]

0.023-

0.047 NS 0.094 14

Single or sequential 

applications may be made 

on each side of the row

with a minimum 

retreatment interval (RTI)

of 45 days for sequential 

applications. Use of an 

NIS is recommended. 

Application to plants 

established less than one 

year is prohibited.

Fruiting Vegetables Group Including But Not Limited to Eggplant, Okra, Pepper, and Tomato

Row

middle/furrow 

applications; 

Ground

(≥15 gal/A; ≥20 

gal/A for okra 

from Section B)

75% WG

[81880-18]

0.023-

0.047 NS 0.094 30

Applications are to be 

made between rows of 

direct-seeded or 

transplanted fruiting 

vegetables.

Pea and Bean, Succulent Shelled, Subgroup 6B 1

[Any succulent shelled cultivar of bean (Phaseolus, spp.), or immature soybean seed (Glycine max), or any Vigna 

spp., and garden pea (Pisum, spp.)] 

Preemergence;

Soil broadcast; 

Ground

(≥15 gal/A)

75% WG

[81880-18] 0.023 1 0.023 30

Timing is after planting 

but before crop 

emergence.
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Table 3. Summary of Directions for Use of Halosulfuron-Methyl.

Applic. Timing, 

Type, and 

Equip.

Formulation

[EPA Reg. 

No.]

Applic. 

Rate 

(lb ai/A)

Max. No. 

Applic. per 

Season

Max. Seasonal 

Applic. Rate

(lb ai/A)

PHI

(days)

Use Directions and 

Limitations

Pea and Bean (Except Soybean), Dried Shelled, Subgroup 6C 1; East of the Rocky Mts.

Postemergence;

Broadcast or 

directed; 

Ground

(≥15 gal/A)

75% WG

[81880-2]

[81880-18]

0.023-

0.031 1

0.047 (per crop 

cycle)

0.094 (per year)

30

Application is to be made 

when plants have 2 to 4 

trifoliate leaves, but 

before flowering. An NIS 

is to be used. Directed 

sprays are recommended.

Pea and Bean (Except Soybean), Dried Shelled, Subgroup 6C; West of the Rocky Mts.

Postemergence;

Broadcast; 

Ground

(≥15 gal/A)

75% WG

[81880-2]

[81880-18]

0.023-

0.047 1

0.047 (per crop 

cycle)

0.094 (per year)

30

Application is to be made 

when plants have 2 to 4 

trifoliate leaves, but 

before flowering. An NIS 

is to be used. Directed 

sprays are recommended.

Rhubarb

Dormant;

Broadcast; 

Ground

(≥15 gal/A)

75% WG

[81880-18]

0.023-

0.047 1 0.047 60

Application is to be made 

as close as possible to 

breaking of dormancy. 

An NIS is to be used if 

labeled weeds have 

emerged.

Tuberous and Corm Vegetables, Subgroup 1C

[Arracacha; arrowroot; artichoke, Chinese; artichoke, Jerusalem; canna, edible; cassava, bitter and sweet; chayote 

(root); chufa; dasheen (taro); ginger; leren; potato; sweet potato; tanier; turmeric; yam bean; yam, true]

Preemergence; 

Soil broadcast; 

Ground

(≥15 gal/A)

75% WG

[81880-18]

0.023-

0.047 2 0.047 45

First application is to be 

made after planting but 

prior to crop emergence; 

if necessary, a second 

application may be made 

45 days before harvest. If 

a second application is 

made, an NIS should be 

used in the second 

application.

Postemergence

Foliar broadcast

Ground

(≥15 gal/A)

1 Individual crop uses of Sandea® Herbicide (EPA Reg. No. 81880-18) are currently registered on succulent beans 

and dry beans; the petitioner now requests uses on Subgroups 6B and 6C. The EP, GWN-3061 Herbicide (EPA 

Reg. No. 81880-2), is also currently registered on soybeans.

The master label for Sandea® Herbicide includes the following additional directions: (1) ground 

applications are to be made in a minimum of 15 gal/A of water; (2) air assisted (airblast) field 

crop sprayers are prohibited; and (3) application through any type of irrigation system is 

prohibited. The label also includes the following statement pertaining to adjuvant use: “Unless 

otherwise stated, a nonionic surfactant (NIS) is recommended in the spray solution for

postemergence applications or for preemergence applications where susceptible weeds are 

present prior to crop emergence.”

Plantback restrictions are also specified on the master label for a number of crops, ranging from 0 

months for sugarcane and insecticide-/imidazolidone- resistant field corn to 36 months for sugar 
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 12 of 34

beet in ND, MN, and the Red River Valley, strawberries (6 months for annual FL transplants), 

and crops not specifically listed. HED previously determined that rotational crop 

tolerances/restrictions are not needed for halosulfuron-methyl. The restrictions appear to have 

been established for protection of the rotated crops from residual herbicidal activity.

Conclusions. The submitted labels for Sandea® Herbicide (EPA Reg. No. 81880-18) and GWN3061 Herbicide (EPA Reg. No. 81880-2) are adequate to allow evaluation of the residue data 

relative to the proposed uses. However, the petitioner is required to i) amend the proposed use 

directions of Sandea® Herbicide (EPA Reg. No. 81880-18) on Crop Subgroup 6B to prohibit 

applications to legumes grown for livestock feeds because no residue data are available for 

cowpea forage and hay; ii) amend the proposed use directions of Sandea® Herbicide (EPA Reg. 

No. 81880-18) on Crop Subgroup 13-07B (bushberry) to remove the instructions pertaining to 

the use of a non-ionic surfactant; iii) remove the use directions from both labels for Crop 

Subgroup 6C (dried pea and bean (except soybean)). Additional recommendations pertaining to 

label amendments maybe found in the respective ‘Magnitude of the Residue’ section and 

summarized in the ‘List of Deficiency’ section.

860.1300 Nature of the Residue - Plants

DP#251007, M. Doherty, 12/10/1998

Metabolism Committee decision, G. Herndon , 5/21/1996

DP#198361, G. Otakie, 7/21/1994

DP#s173627 & 180565, G. Herndon, 7/30/1992

The nature of the residue in plants is adequately understood based on acceptable metabolism 

studies reflecting pre- and postemergence modes of applications on corn, sugarcane, and 

soybean. The metabolism of halosulfuron-methyl was similar in the three tested crops but 

dependent on the mode of application. 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 has 

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

860.1300 Nature of the Residue - Livestock

DP#223801, 11/17/1998, M. Doherty

Metabolism Committee decision, G. Herndon, 5/21/1996

DP#204062, G. Herndon, 6/22/1994

DP#184435, G. Herndon, 1/15/1993

DP#181023, G. Herndon, 11/12/1992

DP#s173627 & 180565, G. Herndon, 7/30/1992
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 13 of 34

An acceptable goat metabolism study was previously submitted and reviewed 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. HED has previously determined that the residue of concern in ruminants is halosulfuronmethyl; 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 in livestock commodities are expressed in terms of 

halosulfuron-methyl and its metabolites determined as 3-CSA, expressed as halosulfuron-methyl 

equivalents. 

There are no poultry feedstuffs associated with the recommended tolerances and crop uses

addressed in this action. Therefore, a discussion of the metabolism of halosulfuron-methyl in 

poultry is not germane to this petition.

860.1340 Residue Analytical Methods

DP#250584, G. Herndon, 10/28/1998

DP#214890, G. Herndon, 5/3/1995

DP#202131, G. Herndon, 10/4/1994

Plants

Enforcement method: An adequate analytical method is available for enforcement of tolerances 

for halosulfuron-methyl residues in plants. The GC method quantifies halosulfuron-methyl as its 

rearrangement ester (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 LOQ 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. Herndon, 10/28/1998). 

N

N

O

CH3

O

CH3

N

H

N

N

CH3

Cl

O

O

CH3

Rearrangement ester (RRE) of halosulfuron-methyl

Data collection methods: Samples collected from the field trial and processing studies

associated with this action were analyzed for residues of halosulfuron-methyl using the available 

tolerance enforcement method, Method RES-109-97-4, with minor 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 
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 14 of 34

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 phosphorus 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. The LLMV

was 0.05 ppm.

Conclusions. The residue analytical methods data are adequate to satisfy data requirements for 

the subject action. An acceptable residue analytical method is available for tolerance 

enforcement purposes for residues in/on crop commodities. Residues of halosulfuron-methyl 

in/on the crop commodities from the magnitude of the residue studies were determined using an 

acceptable data collection method.

Livestock

Enforcement method: An adequate analytical method is available for enforcement of tolerances 

for secondary residues of halosulfuron-methyl in livestock commodities. Monsanto Analytical 

Method RES-046-93 quantifies halosulfuron-methyl and metabolites containing the 3-CSA 

moiety, expressed as parent equivalents. Residues of halosulfuron-methyl and 3-

chlorosulfonamide ester are hydrolyzed to 3-CSA, which is extracted with ACN/DCM and then 

methylated with trimethylsilyl-diazomethane. The methyl ester is analyzed by GC with electroncapture detection (ECD) after cleanup with an alumina/carbon column. The petitioner-validated 

LOQ was 0.01 ppm. The method has been validated as an enforcement method by the Analytical 

Chemistry Branch (ACB)/BEAD at an LOQ of 0.01 ppm in milk and liver (D. Swineford, 

4/28/1995).

860.1360 Multiresidue Methods

DP# 189198, G.Herndon, 3/8/1994

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

The storage durations and conditions of crop samples from the submitted magnitude of the 

residue and processing studies are presented in Table 4.
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

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Table 4. Summary of Storage Conditions and Durations of Samples from Crop Field Trials. 

Matrix Storage 

Temperature (°C)

Actual Storage 

Duration

Interval of Demonstrated 

Storage Stability for Halosulfuron-methyl 1

Apple fruit

≤-4 at the field sites

≤-8 at the analytical 

facility

78-110 days

(2.6-3.6 months) Up to 104 days (3.4 months) in/on frozen apple 

fruit

Blueberry fruit ≤-2 at the field sites

≤-20 at the analytical 

facility

76-125 days

(2.5-4.1 months) Up to 146 or 175 days (4.8 or 5.7 months) in/on 

frozen blueberry fruit

Dry bean seed ≤-10 at the field sites

≤-12 at the analytical 

facility

293-328 days

(9.6-10.8 months)

Up to 326 days (10.7 months) in/on frozen bean 

seed

Succulent pea seed ≤-10 at the field sites 

(on blue ice at the GA 

site)

≤-20 at the analytical 

facility

64-222 days

(2.1-7.3 months)

Up to 242 days (8.0 months) in/on frozen pea seed

Potato tuber ≤-2 at the field sites

≤-20 at the analytical 

facility

114-279 days

(3.7-9.2 months)

Up to 284 days (9.3 months) in/on frozen potato 

tuber

Potato tuber (RAC) ≤-20 at the analytical 

facility

246 days

(8.1 months)

Up to 284 days (9.3 months), 302 days (9.9 

months), 297 days (9.8 months), and 288 days (9.5 

months) in/on frozen potato tuber, flakes/granules, 

chips, and wet peel, respectively

Potato granules/flakes Shipped directly to 

processor at ambient 

temperature

≤-12 at the processing 

facility

≤-20 at the analytical 

facility

296-300 days

(9.7-9.9 months)

Potato chips 292 days

(9.6 months)

Potato wet peel 244-251 days

(8.0-8.2 months)

Rhubarb petiole ≤-5 at the field sites

<-20 at the analytical 

facility

113-165 days

(3.7-5.4 months)

Up to 169 or 233 days (5.6 or 7.7 months) in/on 

frozen rhubarb petiole

1 Storage stability determined from concurrent field trial samples.

To support the current apple, blueberry, dry bean, succulent pea, potato, and rhubarb field trial 

and potato processing data, storage stability studies were conducted in conjunction with the field 

trials and processing study. For each crop, control samples of the respective matrices were 

fortified with halosulfuron-methyl at 0.5 ppm and placed in storage under the same frozen 

conditions as the treated samples. No zero-day analyses were conducted on the fortified samples 

placed into storage. Rather, triplicate stored samples were analyzed along with a control sample 

and freshly fortified samples at an interval reflecting the maximum storage intervals from the 

field trials. Average corrected recoveries of halosulfuron-methyl following frozen storage were 

96% from apple after 104 days, 93% for blueberry after 175 days, 95% from dry bean seed after 

326 days, 102% for succulent pea seed after 242 days, 99% from potato tuber after 284 days, 98-

115% from potato processed commodities after 288-302 days, and 90% from rhubarb after 233 

days. Although no 0-day analysis was conducted, the data indicate that halosulfuro-methyl is 

stable under frozen storage conditions for up to 3.4 months in apple, 5.7 months in blueberry, 

10.7 months in dry bean seed, 8.0 months in succulent pea seed, 9.3 months in potato tuber, 9.5-

9.9 months in potato processed commodities, and 7.7 months in rhubarb.

Conclusions. Adequate storage stability data are available to support the storage conditions and 

durations of samples collected from the magnitude of the residue and processing studies on 

apples, blueberry, dry bean seed, succulent pea seed, potato tuber, potato processed commodities, 
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 16 of 34

and rhubarb. As residues of halosulfuron-methyl were found stable in tested crop matrices, 

storage stability corrections need not be applied to the recommended tolerances for halosulfuronmethyl residues for these commodities.

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

DP#s189198 & 198051, G. Herndon, 3/8/1994

DP#s173627 & 180565, G. Herndon, 7/30/1992

The livestock feedstuffs associated with the proposed uses are wet apple pomace and potato culls 

and processed waste. The feedstuffs derived from registered uses include those commodities 

derived from alfalfa, almond, corn, cotton, dry and snap beans, rice, sorghum, soybean, and 

sugarcane. The dietary burdens of halosulfuron-methyl to beef and dairy cattle resulting from the 

proposed and registered uses are presented in Table 5a. There are no poultry and swine 

feedstuffs associated with the proposed uses. The dietary burdens were re-calculated according 

to the Agency guidance on constructing maximum reasonably balanced diets (June 30, 2008) and 

used the proposed and existing tolerances for feedstuffs. The calculated dietary burdens are 

0.468 ppm for beef cattle and 0.825 ppm for dairy cattle.

Table 5a. Calculation of Dietary Burdens of Halosulfuron-methyl Residues to Livestock.

Feedstuff Type1 % Dry 

Matter2 % Diet2 Recommended Tolerance (ppm)

Dietary Contribution 

(ppm)

3

Beef Cattle

Alfalfa, hay R 89 15 2.0 0.337

Potato, processed waste CC 15 30 0.05 0.100

Corn, field, grain CC 88 50 0.05 0.028

Soybean, meal PC 92 5 0.05 0.003

TOTAL BURDEN -- -- 100 -- 0.468

Dairy Cattle

Alfalfa, forage R 35 20 1.0 0.571

Corn, field, stover R 83 15 0.80 0.145

Corn, field, forage R 40 10 0.20 0.050

Potato, processed waste CC 15 10 0.05 0.033

Corn, field, grain CC 88 35 0.05 0.020

Cotton, meal PC 89 10 0.05 0.006

TOTAL BURDEN -- -- 100 -- 0.825

1

 R: Roughage; CC: Carbohydrate concentrate; PC: Protein concentrate.

2

 OPPTS 860.1000 Table 1 Feedstuffs (June 2008).

3

 Contribution = ([tolerance /% DM] X % diet) for beef and dairy cattle; contribution = ([tolerance] X % diet) for 

poultry and swine.
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

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An adequate dairy cattle feeding study was reported in PP#3F4193 (DP#s 189198 and 198051, 

G. Herndon, 3/8/1994). Halosulfuron-methyl (MON 1200) was administered in gelatin capsules 

to lactating dairy cattle (four animals/dose group) once daily for 28 consecutive days at 3 dose 

levels (roughly equivalent to 0.5, 1.5, and 5 ppm in the daily diet on a dry weight basis). Four 

control animals were given untreated capsules. Milk samples were collected from each a.m. and 

p.m. milking from Day 1 until the day of sacrifice. Within 12 hours after the last dose of test 

material, the animals were sacrificed, and samples of liver, kidney, fat, and muscle were 

collected, finely ground, and frozen until analysis. The samples were analyzed either by Method 

RES-021-92 (milk samples) or Method RES-027-92 (meat matrices). Both methods convert 

halosulfuron-methyl (MON 12000), MON 12000 acid, des-methyl MON 12000, and 

chlorosulfonamide ester to a single chemophore, chlorosulfonamide acid. Prior to sample 

analysis, the performance of the methods was tested using both unlabeled MON 12000 

fortifications as well as the radiolabeled goat milk and liver samples obtained from the carbon-14 

goat metabolism study. Adequate storage stability of MON 12000 in the various matrices was 

shown to cover the storage interval of the samples. No residues were detected in the controls 

above the 0.01 ppm detection limit. The results of the cattle feeding study are shown in Table 

5b.

Table 5b. Maximum Residues in Dairy Cattle Tissues and Milk.

Dose

(ppm)

Maximum Residue (ppm) 1

Whole Milk Raw Cream Raw Skim Milk Muscle Fat Liver Kidney

0.5 NA 2 NA NA NA NA 0.01 0.02

1.5 NA NA NA <0.01 <0.01 0.04 0.11

5.0 <0.01 <0.01 <0.01 <0.01 <0.01 0.11 0.24

1

 Total CSA, expressed as MON 12000 equivalents.

2

 NA – not analyzed.

No detectable residues (<0.01 ppm) were found in milk, muscle, and fat of cattle at feeding levels

of 0.5, 1.5, and 5.0 ppm. Detectable residues were found in liver and kidney at all feeding levels.

Conclusions. The livestock feedstuffs derived from registered and proposed uses would not 

significantly increase the dietary burdens of halosulfuron-methyl to beef and dairy cattle provided 

the petitioner amends the proposed use directions of Sandea® Herbicide on Crop Subgroup 6B to 

prohibit applications to legumes grown for livestock feeds. The available dairy cattle feeding 

study is adequate, and ARIA continues to conclude that tolerances for halosulfuron-methyl 

residues of concern need not be established for the milk, meat, and fat of cattle, goat, hog, horse, 

and sheep. The established tolerance of 0.1 ppm for the meat byproducts of cattle, goat, hog, 

horse, and sheep remain adequate. There are no poultry and swine feedstuffs associated with the 

recommended tolerances and crop uses. The petitioner should note that if additional uses are 

proposed in the future which would result in an increase in the dietary burdens, ARIA/HED will 

re-assess the adequacy of established animal tolerances.
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 18 of 34

860.1500 Crop Field Trials

DER References: 47772101.der.doc (Succulent Pea)

47772102.de1.doc (Potato)

47772103.der.doc (Rhubarb)

47772104.der.doc (Blueberry)

47772105.der.doc (Dry Bean)

47772106.der.doc (Apple)

IR-4 has submitted magnitude of the residue studies on apples, blueberry, dry bean, succulent 

pea, potato, and rhubarb. The results from these field trials are discussed below and the residue 

data are summarized in Table 6. As all residues in/on treated commodity samples were below 

the LLMV (<0.05 ppm) when the test formulation was applied to the crops according to the 

conditions and parameters used in the field trials, the Agency’s tolerance spreadsheet was not 

used for tolerance assessments and recommendations.

Table 6. Summary of Residue Data from Crop Field Trials with Halosulfuron-methyl.

Crop Matrix Total Applic. 

Rate

(lb ai/A)

PHI 

(days)

Residues of Halosulfuron-methyl (ppm)

n Min. Max. HAFT1 Median Mean Std. Dev.

Apple

(proposed use = 0.094 lb ai/A total application rate, 14-day PHI)

Apple (fruit) 0.092-0.104 13-14 26 <0.05 <0.05 <0.05 0.05 0.05 --

Bushberry Subgroup 13-07B

(proposed use = 0.094 lb ai/A total application rate, 14-day PHI)

Blueberry (fruit) 0.093-0.099 13-14 12 <0.05 <0.05 <0.05 0.05 0.05 --

Okra

(proposed use = 0.094 lb ai/A total application rate, 30-day PHI)

Okra No okra data were submitted.

Pea and Bean, Succulent Shelled, Subgroup 6B

(proposed use = 0.023 lb ai/A total application rate, 30-day PHI)

Pea seed 0.032 55-68 4 <0.05 <0.05 <0.05 0.05 0.05 --

0.060-0.070 55-72; 

1662

18 <0.05 <0.05 <0.05 0.05 0.05 --

Pea seed in pods 0.065-0.066 69-77 6 <0.05 <0.05 <0.05 0.05 0.05 --

Pea and Bean (Except Soybean), Dried Shelled, Subgroup 6C

(proposed use = 0.047 lb ai/A total application rate per crop cycle and 0.094 lb ai/A total application rate per year, 

30-day PHI)

Dry bean seed 0.061-0.075 27-31 24 <0.05 <0.05 <0.05 0.05 0.05 --

Rhubarb

(proposed use = 0.047 lb ai/A total application rate, 60-day PHI)

Rhubarb petiole 0.093-0.101 61-78 8 <0.05 <0.05 <0.05 0.05 0.05 --

Tuberous and Corm Vegetables, Subgroup 1C

(proposed use = 0.047 lb ai/A total application rate, 45-day PHI)

Potato tuber 0.094-0.103 42-46 28 <0.05 <0.05 <0.05 0.05 0.05 --

1

 HAFT = highest average field trial result.

2

Includes one trial (2 samples) harvested at a 166-day PHI.
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 19 of 34

Apple

IR-4 has submitted field trial data for halosulfuron-methyl with apple from 13 field trials 

conducted in the United States in Zones 1 (NY; 3 trials), 2 (NJ, NC; 2 trials), 5 (MI; 2 trials), 9 

(CO; 1 trial), 10 (CA; 1 trial), and 11 (ID, WA; 4 trials) during the 2006 growing season. At 

each trial site, two broadcast applications of a 75% WG formulation of halosulfuron-methyl were 

made to the orchard floor during the fruiting growth stages, at 0.044-0.053 lb ai/A/application, 

with a 13- to 15-day retreatment interval (RTI), for a total rate of 0.092-0.104 lb ai/A (~1X the 

proposed maximum seasonal rate). Applications were made using ground equipment in spray

volumes of 15-36 gal/A, without an adjuvant. Samples of commercially mature apple fruit were 

collected at a 13- to 14-day PHI. An additional plot was established at the NJ site using a total 

seasonal rate of 0.484 lb ai/A, to generate samples for processing; however, as residues were 

nondetectable in any apple fruit sample, processing was not initiated.

Samples of apple fruit were analyzed for residues of halosulfuron-methyl as its rearrangement 

ester using the available tolerance enforcement method, Method RES-109-97-4, with 

modifications. The gas chromatography method with nitrogen-phosphorus detection (GC/NPD) 

is adequate for data collection based on acceptable method validation and concurrent method 

recoveries. The LLMV for halosulfuron-methyl in apple was 0.05 ppm.

The maximum storage duration for apple fruit samples was 110 days (3.6 months). To support 

sample storage conditions and durations, storage stability data were generated concurrently with 

the field trial study. These data demonstrate that residues of halosulfuron-methyl are stable in/on 

fortified apple fruit stored frozen for up to 104 days (3.4 months).

Residues of halosulfuron-methyl were below the LLMV (<0.05 ppm) in/on all samples of apple 

fruit harvested 13 or 14 days following the second of two broadcast applications of the 75% WG 

formulation of halosulfuron-methyl at a total seasonal rate of 0.092-0.104 lb ai/A.

Conclusions: The submitted field trial data for halosulfuron-methyl on apples are adequate with 

regard to the number and location of field trials. The application rate and PHI reflect the 

proposed use pattern, and the data are supported by concurrent storage stability data. Although

the apple data did not reflect the use of a nonionic surfactant as recommended on the proposed 

label, this is not an issue as the application is directed to the orchard floor and presence/absence 

of surfactant is not expected to change the residue level on the apple fruit. The available data 

will support the proposed tolerance of 0.05 ppm for apple. 
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 20 of 34

Bushberry Subgroup 13-07B

IR-4 has submitted field trial data for halosulfuron-methyl with blueberry as a representative of 

the Crop Subgroup 13-07B, bushberry. Six blueberry trials were conducted in the United States 

in Zones 1 (ME; 1 trial), 2 (NJ and NC; 2 trials), 5 (MI; 2 trials), and 12 (OR; 1 trial), during the 

2006 growing season. At each trial location, a single soil broadcast application of a 75% WG 

formulation of halosulfuron-methyl was made during the crops’ fruiting growth stage at a rate of 

0.093-0.099 lb ai/A (~1X the proposed maximum rate). Applications were made to either side of 

each plant row using ground equipment in spray volumes of ~16-23 gal/A except for the OR trial 

where a spray volume of 62 gal/A was used; no adjuvant was included in any of the spray 

volumes. Samples of commercially mature blueberry fruit were collected at a 13- or 14-day PHI.

Samples of blueberry fruit were analyzed for residues of halosulfuron-methyl as its 

rearrangement ester using the available tolerance enforcement method, Method RES-109-97-4, 

with modifications. The GC/NPD is adequate for data collection based on acceptable method 

validation and concurrent method recoveries. The LLMV for halosulfuron-methyl in blueberry

fruit was 0.05 ppm.

The maximum storage duration for blueberry samples was 125 days (4.1 months). To support 

sample storage conditions and durations, storage stability study data were generated concurrently

with the field trial study. These data demonstrate that residues of halosulfuron-methyl are stable 

in/on fortified blueberry fruit stored frozen for up to 175 days (5.7 months).

Residues of halosulfuron-methyl were below the LLMV (<0.05 ppm) in/on all samples of 

blueberry harvested 13 or 14 days following a single soil broadcast application of the 75% WG

formulation of halosulfuron-methyl at 0.093-0.099 lb ai/A.

Conclusions: The submitted field trial data for halosulfuron-methyl on blueberries, the 

representative commodity of Crop Subgroup 13-07B, are adequate with regard to the number and 

location of field trials. Although the number of field trials is a 25% reduction of the OPPTS 

860.1500 guidance, this number is considered sufficient, for halosulfuron-methyl, to support the

Subgroup 13-07B tolerance based on the lack of quantifiable residues. The application rate and 

PHI reflect the proposed use pattern, and the data are supported by concurrent storage stability

data. However, the blueberry data did not reflect the use of a nonionic surfactant as 

recommended on the proposed label. The blueberry data will support and ARIA recommends for 

the proposed tolerance of 0.05 ppm for the bushberry Subgroup 13-07B provided the label for 

Sandea® Herbicide is amended to remove the instructions pertaining to the use of a non-ionic 

surfactant on crops belonging to the Subgroup 13-07B. If it is IR-4’s intention to add a nonionic 

surfactant when Sandea® Herbicide is applied on Subgroup 13-07B, then additional field trial 

data are required. Although the spray is directed to the rows between blueberry bushes, there is a 

finite possibility of the spray contacting the bushes, and the presence/absence of surfactant might 

impact the residue on the blueberries.
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 21 of 34

Okra

DP#267423, A. Acierto, 4/25/2002

No residue data were submitted to support the proposed use on okra. Okra was listed by the 

petitioner in its proposed labels as part of the fruiting vegetables crop group. The ChemSAC 

meeting of 10/18/2006 has recommended the inclusion of okra in Crop Group 8 (fruiting 

vegetables). The ChemSAC has also determined that a separate tolerance for okra should be 

listed in the appropriate section of the CFR entry until the new crop group regulation is 

published.

A tolerance of 0.05 ppm for residues of halosulfuron-methyl has been established on the fruiting 

vegetable Crop Group 8 based on field trial data for tomato and pepper (DP#267423, A. Acierto, 

4/25/2002). The available field trial data for fruiting vegetables will be translated to okra. ARIA 

recommends for the establishment of a tolerance of 0.05 ppm for residues of halosulfuron-methyl

in/on okra. This recommendation is identical to the level proposed by the petitioner.

Pea and Bean, Succulent Shelled, Subgroup 6B

DP#278587, A. Acierto, 6/15/2002

IR-4 has submitted field trial data for halosulfuron-methyl on succulent shelled and edible 

podded peas from 12 field trials conducted in the United States during the 2003-2004 growing 

seasons. Nine trials on succulent shelled peas were conducted in Zones 2 (GA and SC; 2 trials), 

5 (OH and WI; 4 trials), 11 (WA; 2 trials), and 12 (OR; 1 trial). Three trials on edible podded 

pea were conducted in Zones 1 (NY; 1 trial) and 10 (CA; 2 trials). Each trial site consisted of 

one untreated plot and two treated plots. Each treated plot received a single postplant 

preemergence broadcast soil application of a 75% WG formulation of halosulfuron-methyl at 

~0.032 lb ai/A (Treatment Plot 2; ~1.4X the maximum proposed rate) or ~0.064 lb ai/A 

(Treatment Plot 3; ~2.8X). All applications were made using ground equipment in 20-38 GPA 

spray volumes, without an adjuvant. Samples of commercially mature pea seed were collected at 

a 55- to 77-day PHI; however, at one trial, peas were collected at a 166-day PHI.

Samples of succulent pea seed, with and without pods, were analyzed for residues of 

halosulfuron-methyl as its RRE using the available tolerance enforcement method, Method RES109-97-4, with modifications. The GC/NPD is adequate for data collection based on acceptable 

method validation and concurrent method recoveries. The LLMV for halosulfuron-methyl was 

0.05 ppm.

The maximum storage duration for pea seed samples was 222 days (7.3 months). To support 

sample storage conditions and durations, a concurrent storage stability study was conducted with 

the field trial study. These data demonstrate that residues of halosulfuron-methyl are stable in/on 

fortified pea seed stored frozen for up to 242 days (8.0 months).

Residues of halosulfuron-methyl were below the LLMV (<0.05 ppm) in/on all samples of peas 

(succulent shelled and edible podded) harvested 55-166 days following a single preemergence 

broadcast application of the 75% WG formulation of halosulfuron-methyl, made to the soil at a 
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 22 of 34

rate of 0.060-0.070 lb ai/A (Treatment Plot 3). Residues were also below the LLMV (<0.05 

ppm in/on samples of pea seeds treated at 0.032 lb ai/A (Treatment Plot 2). Varying degrees of 

phytotoxicity were reported at all but three of the test sites. The petitioner reported phytotoxic 

effects resulting in plant stunting/thinning or chlorosis at the NY, OH, SC, WI, and WA trial 

sites, and one CA trial site. No phytotoxic effects were noted at the three remaining trials. 

Although phytotoxicity appears to be attributed to the test substance application, these instances 

of phytotoxicity did not have an adverse impact on the residue trials.

Conclusions: The representative crops of Subgroup 6B are two commodities of: (1) any

succulent shelled cultivar of bean (Phaseolus spp.) or (2) immature soybean seed (Glycine max) 

or (3) any Vigna spp. and garden pea (Pisum spp.). The submitted field trial data for succulent 

peas do not fully support the proposed use pattern because the trials were conducted at 

exaggerated rates (1.4X or 2.8X) and the collected samples did not reflect the proposed 30-day

PHI (the earliest PHI tested was 55 days). The available data for succulent beans, previously

submitted under PP#1E06322 (DP#278587, A. Acierto, 6/15/2002) to support the established 

individual tolerance of 0.05 ppm, also do not reflect the proposed use on Subgroup 6B because 

these data represent foliar application whereas the new proposed use pattern is for preemergence 

soil application. 

ARIA will not require additional data on succulent peas since treatment at 1X will likely result in 

residues below 0.05 ppm, even when harvested at a PHI of 30-days. ARIA will also not require 

additional data on succulent beans since soil treatment will likely result in residues below 0.05 

ppm. ARIA recommends for the proposed tolerance of 0.05 ppm for the Subgroup 6B (pea and 

bean, succulent shelled). Concomitant with the establishment of a tolerance for Subgroup 6B, 

the individual tolerance for ‘bean, snap, succulent’ should be revoked.

Pea and Bean (Except Soybean), Dried Shelled, Subgroup 6C

DP# 278587, A. Acierto, 6/15/2002

IR-4 has submitted field trial data for halosulfuron-methyl with dry bean as a representative of 

the Crop Subgroup 6C dried shelled bean (except soybean) and pea. Twelve field trials were 

conducted in the United States with dry bean in Zones 1 (NY; 1 trial), 5 (ND, SD, and WI; 5 

trials), 7 (NE and ND; 2 trials), 8 or 9 (CO; 2 trials), 10 (CA; 1 trial), and 11 (WA; 1 trial) during 

the 2005 growing season. At each trial site, a single foliar broadcast postemergence application 

of a 75% WG formulation of halosulfuron-methyl was made during the crop’s blooming or 

fruiting growth stage at 0.061-0.075 lb ai/A (~1.3-1.6X the proposed application rate per crop 

cycle and ~0.6-0.8X the proposed total application rate per year). Applications were made using 

ground equipment in spray volumes of ~18-35 gal/A; an NIS was added as an adjuvant. Samples 

of commercially mature dry bean seed were collected at a 27- to 31-day PHI.

Samples of dry bean seed were analyzed for residues of halosulfuron-methyl as its RRE using the 

available tolerance enforcement method, Method RES-109-97-4, with modifications. The 

GC/NPD is adequate for data collection based on acceptable method validation and concurrent 

method recoveries. The LLMV for halosulfuron-methyl in dry bean seed was 0.05 ppm.

The maximum storage duration for dry bean seed samples was 328 days (10.8 months). To 

support sample storage conditions and durations, storage stability study data were generated 
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 23 of 34

concurrently with the field trial study. These data demonstrate that residues of halosulfuronmethyl are stable in/on fortified dry bean seed stored frozen for up to 326 days (10.7 months).

Residues of halosulfuron-methyl were below the LLMV (<0.05 ppm) in/on all samples of dry

bean seed harvested 27 to 31 days following a single foliar broadcast postemergence application 

of the 75% WG formulation of halosulfuron-methyl at 0.061-0.075 lb ai/A.

Conclusions: The representative commodities of Subgroup 6C are any one dried cultivar of bean 

(Phaseolus spp.) and any one dried cultivar of pea (Pisum spp.) The submitted residue data for 

dry bean are adequate with regard to geographic representation of data; the data are supported by

concurrent storage stability data. The dry bean data from the current submission reflect a single 

foliar broadcast application conducted at ~1.6X the proposed application rate per crop cycle (or 

~0.8X the proposed total application rate per year), the use of a nonionic surfactant, and the 

treated samples were collected approximating the proposed 30-day PHI. Additional data for dry

beans were submitted under PP#1E06322 (DP#278587, A. Acierto, 6/15/2002) to support the 

established individual tolerance of 0.05 ppm. These data represent a single application of Permit 

75 WG Herbicide at 0.032 lb ai/A made 0 to 6 days after planting and a 86- to 113-day PHI.

ARIA is unable to recommend for the proposed tolerance of 0.05 ppm for Crop Subgroup 6C 

(Dried Shelled Bean (Except Soybean) and Pea) at this time because residue data on dried pea 

including the forages and hay of field pea cultivars are required. When adequate residue data for 

dried peas become available, the petitioner may again request a tolerance for Subgroup 6C. A 

revised Section F should be submitted removing the request for Crop Subgroup 6C (dried shelled 

pea and bean (except soybean)).

Rhubarb

IR-4 has submitted field trial data for halosulfuron-methyl on rhubarb from four field trials 

conducted in the United States in Zones 5 (MI; 1 trial) and 12 (OR; 3 trials) during the 2006 

growing season. At each trial location, a single soil broadcast application of a 75% WG 

formulation of halosulfuron-methyl was made at the end of plant dormancy, at a rate of 0.093-

0.101 lb ai/A (~2.0-2.1X the proposed rate). Applications were made using ground equipment in 

spray volumes of ~20-32 gal/A; an NIS was added as an adjuvant. Samples of rhubarb petiole 

(stalk plus leaf) were collected at a 61- to 78-day PHI.

Samples of rhubarb petiole were analyzed for residues of halosulfuron-methyl as its RRE using 

the available tolerance enforcement method, Method RES-109-97-4, with modifications. The 

GC/NPD is adequate for data collection based on acceptable method validation and concurrent 

method recoveries. The LLMV for halosulfuron-methyl in rhubarb was 0.05 ppm.

The maximum storage duration for rhubarb petiole samples was 165 days (5.4 months). To 

support sample storage conditions and durations, a concurrent storage stability study was 

conducted with the field trial study. These data demonstrate that residues of halosulfuron-methyl 

are stable in/on fortified rhubarb stored frozen for up to 233 days (7.7 months).

Residues of halosulfuron-methyl were below the LLMV (<0.05 ppm) in/on all samples of 

rhubarb petiole harvested 61 to 78 days following a single soil broadcast application of the 75% 
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 24 of 34

WG formulation of halosulfuron-methyl at 0.093-0.101 lb ai/A.

Conclusions: The submitted field trial data for halosulfuron-methyl on rhubarb are adequate with

regard to the number and location of field trials. The data also reflect the use of nonionic 

surfactant as recommended on the proposed label, samples were collected at appropriate PHI, 

and are supported by concurrent storage stability data. However, the rhubarb data were generated 

using slightly exaggerated rates of ~2.0-2.1X. ARIA will not require additional data on rhubarb 

since treatment at 1X will likely result in residues below 0.05 ppm. The available data will

support the proposed tolerance of 0.05 ppm for rhubarb.

Tuberous and Corm Vegetables, Subgroup 1C

IR-4 has submitted field trial data for halosulfuron-methyl with potato as a representative of the 

Crop Subgroup 1C tuberous and corm vegetables. Fourteen potato trials were conducted in the 

United States in Zones 1 (ME and NY; 2 trials), 2 (NJ; 1 trial), 3 (FL; 1 trial), 5 (ND and WI; 3 

trials), 9 (CO; 1 trial), 10 (CA; 1 trial), and 11 (ID and WA; 5 trials), during the 2004 growing 

season. At each test location, two broadcast applications of a 75% WG formulation of 

halosulfuron-methyl were made at 0.046-0.052 lb ai/A/application for a total seasonal rate of 

0.094-0.10 lb ai/A (~2.0-2.1X the proposed maximum seasonal rate). The first application was 

made to bare soil; the second was made as a foliar application 27 to 96 days later when the plants 

were in a vegetative to post bloom growth stage. Applications were made using ground 

equipment in spray volumes of ~12-32 gal/A. The first application did not include an adjuvant, 

but the second included a non-ionic surfactant. Samples of commercially mature potato tuber 

were collected at a 42- to 46-day PHI. At one WA site, additional bulk samples of potato tuber 

were collected for processing.

Samples of potato tuber were analyzed for residues of halosulfuron-methyl as its RRE using the 

available tolerance enforcement method, Method RES-109-97-4, with modifications. The 

GC/NPD is adequate for data collection based on acceptable method validation and concurrent 

method recoveries. The LLMV for halosulfuron-methyl was 0.05 ppm.

The maximum storage duration for potato tuber samples was 279 days (9.2 months). To support 

sample storage conditions and durations, storage stability study data were generated concurrently

with the field trial study. These data demonstrate that residues of halosulfuron-methyl are stable 

in/on fortified potato tuber stored frozen for up to 284 days (9.3 months).

Residues of halosulfuron-methyl were below the LLMV (<0.05 ppm) in/on all samples of potato 

tuber harvested 42 to 46 days following the second of two broadcast applications (soil followed 

by foliar) of the 75% WG formulation of halosulfuron-methyl, made during fruiting with a total 

seasonal rate of 0.094-0.103 lb ai/A. Varying degrees of phytotoxicity (i.e., stunting, some 

chlorosis, slight browning of leaf edge) following application of halosulfuron-methyl were 

reported at some of the test sites (CA, CO, ND, and WI). No phytotoxic effects were noted at the 

remaining trials. Although phytotoxicity appears to be attributed to the test substance 

application, these instances of phytotoxicity did not have an adverse impact on the residue trials.
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 25 of 34

Conclusions: The submitted field trial data for halosulfuron-methyl on potato, the representative 

commodity of Crop Subgroup 1C, reflect the use of a nonionic surfactant as recommended on the

proposed label and approximate the proposed PHI. The data are also supported by concurrent 

storage stability data. However, the number and location of field trials do not fully conform to 

the OPPTS 860.1500 guideline as only 14 trials were conducted whereas the guideline requires a 

minimum of 16 trials to support a tolerance on Crop Group 1C. In addition, the potato data were 

generated using slightly exaggerated rates of ~2.0-2.1X. ARIA will not require additional data 

on potatoes since additional trials at a 1X rate will likely result in residues below 0.05 ppm. The 

available data will support the proposed use pattern and ARIA recommends for a tolerance of 

0.05 ppm for Crop Subgroup 1C.

860.1520 Processed Food and Feed

Apple

DER References: 47772106.der.doc

An additional plot was established at the NJ site using a total seasonal rate of 0.484 lb ai/A 

(~5.1X the proposed maximum seasonal rate), to generate samples for processing; however, as 

residues were nondetectable in any apple fruit sample, a processing study was not initiated. 

Conclusions. These data are adequate to conclude that additional apple processing study and 

tolerances for apple processed commodities are not required for this action.

Potato

DER Reference: 47772102.de2

In a single crop field trial conducted in WA during the 2004 growing season, two broadcast 

applications of a 75% WG formulation of halosulfuron-methyl, were made to bare soil and then 

to potato plants at the vegetative/fruiting growth stage, at 0.049-0.050 lb ai/A/application, with a 

95-day RTI, for a total rate of 0.099 lb ai/A (2X the proposed maximum seasonal rate). 

Applications were made using ground equipment in a spray volume of ~18 gal/A, with an NIS 

included in the second application as an adjuvant. Mature potato tuber was harvested at a 42-day

PHI and processed into granules/flakes, chips, and wet peel using procedures simulating 

commercial practices.

Samples of potato tuber, granules/flakes, chips, and wet peel were analyzed for residues of 

halosulfuron-methyl as its RRE using the available tolerance enforcement method, Method RES109-97-4, with modifications. The GC/NPD is adequate for data collection based on acceptable 

method validation and concurrent method recoveries. The LLMV for halosulfuron-methyl was 

0.05 ppm in all potato matrices.

The maximum storage durations of samples from harvest/processing to analysis were 246 days 

(8.1 months) for potato tuber and 251-300 days (8.2-9.9 months) for potato granules/flakes, 

chips, and wet peel. To support sample storage conditions and durations, a concurrent storage 

stability study was conducted with the processing study. These data demonstrate that residues of 

halosulfuron-methyl are stable for up to 284 days (9.3 months), 302 days (9.9 months), 297 days 
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 26 of 34

(9.8 months), and 288 days (9.5 months) in/on frozen potato tuber, flakes/granules, chips, and 

wet peel, respectively. However, zero-day data were not provided.

The results of the potato processing study are summarized in Table 7. Residues of halosulfuronmethyl were nonquantifiable (<0.05 ppm) in/on potato tuber harvested 42 days following the 

second of two broadcast applications of the 75% WG formulation of halosulfuron-methyl, made 

to soil and at the vegetative/fruiting growth stage at a total rate of 0.099 lb ai/A. Residues were 

also nonquantifiable in processed potato granules/flakes, chips, and wet peel, therefore, 

processing factors could not be calculated.

Theoretical concentration factors based on loss of water (860.1520, Table 2) are 4.7X for potato 

granules/flakes and, based on separation into components, 4.0X for potato processed waste 

(860.1520, Table 3). The maximum theoretical concentration factor for potato is 5X (860.1520, 

Table 1).

Table 7. Residue Data from Potato Processing Study with Halosulfuron-methyl.

RAC Processed Commodity Total Rate

(lb ai/A) 

PHI 

(days)

Residues (ppm)1Processing 

Factor

Potato Tuber (RAC) 0.099 42 ND, ND --

Flakes/granules ND, ND Not calculated2

Chips ND, ND

Wet peel ND, ND

1

 ND = Not detected. Residues reported below the LOD (<0.0089 ppm in/on tuber; <0.0129 ppm in flakes/granules; <0.0307 

ppm in chips; and <0.0402 ppm in wet peel).

2

 Not calculated because residues were reported blow the LLMV (<0.05 ppm) in both the RAC and the processed commodity.

Conclusions. The submitted processing data for potato are acceptable. Residues of 

halosulfuron-methyl were nonquantifiable (<0.05 ppm) in/on potato tubers following treatments 

at 2X the proposed seasonal rate. Residues were also nonquantifiable in processed potato 

granules/flakes, chips, and wet peel. The Agency would have preferred that a trial with an 

exaggerated rate equal to or higher than the maximum theoretical concentration factor of 5X for 

potato have been conducted. However, because of phytotoxicity limitations as reported in the 

magnitude of the residue trials, a new potato processing study will not be required. Based on 

these data, tolerances for potato processed commodities are not needed.

860.1650 Submittal of Analytical Reference Standards

DP#250584, G. Herndon, 10/28/1998

An analytical standard is currently available in the EPA National Pesticide Standards Repository

for halosulfuron-methyl (expiration 6/14/2013); however, a standard is not available for its 3-

CSA (3-chlorosulfonamide acid) metabolite (personal communication with Dallas Wright, ACB, 

2/23/2009). ARIA notes that a standard for the 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
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 27 of 34

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

DP#225273, G.J. Herndon, 10/29/1998

Metabolism Committee decision, G. Herndon , 5/21/1996

DP#192510, G. Kramer, 8/30/1993

DP#s 188144 and 188814, G. Herndon, 3/11/1993

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.

Conclusion. The proposed uses on okra, pea and bean (succulent shelled and dried), tuberous 

and corm vegetables, and rhubarb are not expected to alter HED’s earlier assessment regarding 

the potential for inadvertent residues in rotatable crops addressed in this registration action. No 

additional data are required. 

860.1550 Proposed Tolerances

Halosulfuron-methyl tolerances for plant commodities have been established in 40 CFR 

§180.479(a)(2) and are expressed in terms of halosulfuron-methyl, methyl 3-chloro-5-[[[[(4,6-

dimethoxy-2-pyrimidinyl)amino] carbonyl] amino] sulfonyl]-1-methyl-1 H -pyrazole-4-

carboxylate. The proposed tolerance expression is consistent with the halosulfuron-methyl 

tolerances established in 40 CFR §180.479(a)(2) and reflect the residues of concern as previously

determined by HED.

Halosulfuron-methyl tolerances for livestock commodities are listed in 40 CFR §180.479(a)(1) 

and are expressed in terms of halosulfuron-methyl and its metabolites determined as 3-chloro-1-

methyl-5-sulfamoylpyrazole-4-carboxylic acid (also referred to as 3-CSA, expressed as parent 

equivalents). 
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 28 of 34

Residues of halosulfuron-methyl were below the LLMV (<0.05 ppm) when the test formulation 

was applied to the proposed crops according to the conditions and parameters used in the field 

trials. The Agency’s tolerance spreadsheet was not used for tolerance assessments and 

recommendations.

For apples, the submitted data will support a RAC tolerance of 0.05 ppm. 

For blueberries, the submitted data will support a tolerance of 0.05 ppm for Crop Subgroup 13-

07B (bushberry) provided the label for Sandea® Herbicide is amended to remove the instructions 

pertaining to the use of a non-ionic surfactant. If it is IR-4’s intention to add a nonionic 

surfactant when Sandea® Herbicide is applied on Subgroup 13-07B, then additional field trial 

data are required.

For okra, the available field trial data for fruiting vegetables will be translated to okra. The 

ChemSAC meeting of 10/18/2006 has recommended the inclusion of okra in Crop Group 8 

(fruiting vegetables). The ChemSAC has also determined that a separate tolerance for okra 

should be listed in the appropriate section of the CFR entry until the new crop group regulation is 

published. The translated data support a tolerance of 0.05 ppm in/on okra.

For Crop Subgroup 6B (pea and bean, succulent shelled), ARIA recommends a tolerance of 0.05 

ppm, provided the proposed labels on Crop Subgroup 6B is amended to prohibit applications to 

legumes grown for livestock feeds. Concomitant with the establishment of a tolerance for 

Subgroup 6B, the individual tolerance for ‘bean, snap, succulent’ should be revoked.

Because data are required for dried pea including the forages and hay of field pea cultivars for 

Crop Subgroup 6C (dried shelled bean (except soybean) and pea), ARIA is unable to recommend 

for a registration and tolerance. When adequate residue data for dried peas become available, the 

petitioner may again request a tolerance for Subgroup 6C.

For rhubarb, the submitted data will support a RAC tolerance of 0.05 ppm.

For potatoes, the submitted data will support a tolerance for Crop Subgroup 1C (tuberous and 

corm vegetables) at 0.05 ppm.

The apple and potato processing data indicate that tolerances are not needed for the processed 

commodities of these crops. 

Tolerances for halosulfuron residues of concern need not be established for the milk, meat, and 

fat of cattle, goat, hog, horse, and sheep as a result of the proposed uses. The established 

tolerance of 0.1 ppm for the meat byproducts of cattle, goat, hog, horse, and sheep remain 

adequate. There are no poultry and swine feedstuffs associated with the recommended tolerances 

and crop uses. The petitioner should note that if additional uses are proposed in the future which 

would result in an increase in the dietary burdens, ARIA/HED will re-assess the adequacy of 

established animal tolerances.

Table 8 presents the proposed/recommended tolerance level and the corrected commodity

definition.
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 29 of 34

There are no Codex, Canadian, or Mexican maximum residue limits (MRLs) established for 

residues of halosulfuron-methy in crop or livestock commodities. An International Residue 

Limit (IRL) form is appended to this Summary Document and follows this section.

Table 8. Tolerance Summary for Halosulfuron-Methyl.

Commodity (as Defined in Section F) Proposed Tolerance 

(ppm)

Recommended 

Tolerance (ppm)

Comments; Correct Commodity 

Definition

PEA AND BEAN, SUCCULENT 

SHELLED, SUBGROUP 6B

0.05 0.05 ARIA recommends a label 

revision to prohibit applications 

to legumes grown for livestock 

feeds because no residue data 

are available for cowpea forage 

and hay.

Pea and bean, succulent 

shelled, subgroup 6B

VEGETABLE TUBEROUS AND 

CORM, SUBGROUP 1C

0.05 0.05 Vegetable, tuberous and corm, 

subgroup 1C

RHUBARB 0.05 0.05 Rhubarb

PEA AND BEAN, DRIED 

SHELLED, EXCEPT SOYBEAN, 

SUBGROUP 6C

0.05 None Revised Section F. When 

adequate residue data for dried 

peas become available, the 

petitioner may again request a 

tolerance for Subgroup 6C.

Pea and bean, dried shelled, 

except soybean, subgroup 6C

APPLE 0.05 0.05 The proposed label should be 

amended to remove the 

instructions pertaining to the 

use of a non-ionic surfactant.

Apple

OKRA 0.05 0.05 The recommended tolerance is 

based on translation of data 

from fruiting vegetables.

Okra

BUSHBERRY SUBGROUP 13-07B 0.05 0.05 The proposed label should be 

amended to remove the 

instructions pertaining to the 

use of a non-ionic surfactant.

Bushberry subgroup 13-07B
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 30 of 34

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. Herndon

To: J. Miller/D. Kenny and A. Kocialski

Dated: 7/30/1992

MRIDs: 42139400-08

DP#: 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. Herndon

To: J. Miller/D. Kenny and A. Kocialski

Dated: 11/12/1992

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. Herndon

To: J. Miller/D. Kenny and A. Kocialski

Dated: 1/15/1993

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. Herndon 

To: J. Miller/D. Kenny and A. Kocialski

Dated: 3/11/1993

MRIDs: None
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 31 of 34

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: 8/30/1993

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. Herndon

To: J. Miller/D. Kenny and A. Kocialski

Dated: 3/8/1994

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. Herndon

To: J. Miller/D. Kenny and A. Kocialski

Dated: 6/22/1994

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: 7/21/1994

MRIDs: 42991201-02
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 32 of 34

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. Herndon

To: J. Miller/D. Kenny and A. Kocialski

Dated: 10/4/1994

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. Herndon

To: J. Miller/D. Kenny and J. Smith

Dated: 5/3/1995

MRIDs: 43195001

DP#: None

Subject: Halosulfuron (MON 12000). The HED Metabolism Committee Meeting Held on 

May 20, 1996.

From: G. Herndon

To: HED Metabolism Committee

Dated: 5/21/1996

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. Herndon

To: V. Walters/ J. Tompkins

Dated: 10/28/1998

MRIDs: 44495801 and 44555901

DP#: 225273

Subject: Halosulfuron. Revised Section F Proposing Deletion of Existing Rotational Crop 

Tolerances.

From: G. Herndon

To: V. Walters/ J. Tompkins

Dated: 10/29/1998

MRIDs: None
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 33 of 34

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: 11/17/1998

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: 12/10/1998

MRIDs: 44689501

DP#: 267423

Subject: PP# 0F06169. Halosulfuron-methyl on Fruiting Vegetables (Except Cucurbits) 

Crop Group 8/ Review of Analytical Methods and Magnitude of Residue Data.

From: A. Acierto

To: J. Tompkins/V. Walters

Dated: 4/25/2002

MRIDs: 45117501, 45117502

DP#: 278587

Subject: PP# 1E06322. Halosulfuron-methyl on Bean, Dry and Bean, Snap. Magnitude of 

Residue Data.

From: A. Acierto

To: R. Forrest/S. Brothers

Dated: 6/15/2002

MRIDs: 45427801, 45427802

Attachments: 

International Residue Limit Status sheet
Halosulfuron-methyl Summary of Analytical Chemistry and Residue Data DP#367058

Page 34 of 34

INTERNATIONAL RESIDUE LIMIT STATUS

Chemical Name: methyl 

5-[(4,6-dimethoxy-2-

pyrimidinyl)amino]carbon

ylaminosulfonyl-3-chloro1-methyl-1H-pyrazole-4-

carboxylate

Common Name:

Halosulfuron-methyl

X Proposed tolerance

□ Reevaluated tolerance

□ Other

Date: 10/2009

Codex Status (Maximum Residue Limits) U. S. Tolerances

X No Codex proposal step 6 or above

□ No Codex proposal step 6 or above for the crops 

requested

Petition Number: PP#9E7577

DP#: 367058

Other Identifier: 

Residue definition (step 8/CXL): N/A Reviewer/Branch: P. Deschamp, N. Dodd/RAB3

Residue definition: halosulfuron-methyl

Crop (s) MRL (mg/kg) Crop(s) Tolerance (ppm)

Pea and bean, succulent 

shelled, Subgroup 6B

0.05

Vegetable, tuberous and corm, 

Subgroup 1C

0.05

Rhubarb 0.05

Pea and bean, dried shelled, 

except soybean, Subgroup 6C

0.05

Apple 0.05

Okra 0.05

Bushberry, Subgroup 13-07B 0.05

Limits for Canada Limits for Mexico

X No Limits

□ No Limits for the crops requested

X No Limits

□ No Limits for the crops requested

Residue definition: N/A Residue definition: N/A

Mexico defers to Codex MRLs or US tolerances for its 

export purposes.

Crop(s) MRL (mg/kg) Crop(s) MRL (mg/kg)

Notes/Special Instructions:

S. Funk, 10/15/2009.