### Page 2 of 30 Executive Summary

The HED Reg istration Review T eam has evaluated human health assessment s for the herbicide
halosulfuron

- methyl to determine whether sufficient data are available and whether any updates are needed to support Registration Review. HED has considered the most recent human

- health
risk assessments for halosulfuron

- methyl, updates to the toxicity, exposure, and usage databases, and current Agency science policy and risk assessment methodologies to determine the scope of work necessary to su pport Registration Review. In addition, HED conducted an open literature
search to look for new literature relevant to the human health risk assessment and found no relevant toxicity or exposure information.

Halosulfuron

- methyl , a sulfonylurea herbicid e, inhibits the action of the plant enzyme acetolactate synthase. Halosulfuron

- methyl has low acute toxicity

. With repeated dosing, halosulfuron produces non

- specific effects, which are frequently characterized by reduced body weight / body weight gain in the test animals. Halosulfuron

- methyl is classified as “not likely to be carcinogenic to humans.” It is negative for mutagenicity in a battery of genotoxicity studies.

The FQPA safety factor is 1X. Although the data indicated an increase in qualitati ve susceptibility in fetuses following prenatal exposure in rats and rabbits, the developmental effects were seen in the presence of maternal effects and clear NOAELs and LOAELs were established for both maternal and developmental effects. In addition, th e developmental effects in rats were seen at doses approaching the limit dose (1000 mg/kg). It was concluded that the degree of concern was low and there was no residual uncertainty in either the rat or rabbit developmental toxicity study. In addition to a lack of residual concerns for susceptibility, there was no evidence of neurotoxicity, and exposures were not considered to be underestimated. T he toxicology database is adequate, with the exception of the requirement for an immunotoxicity study

. Th is stud y was required as a condition of registration. The 28

- day inhalation toxicity study , also a condition of registration, was waived ( Hazard and Science Policy Council ( HASPOC ) Meeting, TXR # 0054045, DP# D 397243 , D. Smegal, MPH, 2/22/12 ).

In addition to the agricultural food uses, halosulfuron

- methyl is also registered for use on turfgrass, ornamentals, and a variety of non

- crop areas including, but not limited to, a irports, cemeteries, fallow non

- crop areas, golf courses, landscaped areas, public recreation areas, residential property, roadsides, school grounds, sod or turf seed farms, sports fields, residential and commercial landscaped areas with established woody ornamentals, fairgrounds, race tracks,
tennis courts , campgrounds, and righ ts

- of

- way.

All residential (turf grass and ornamentals) and occupational exposure scenarios were not assessed based on current policies. Also, residential and occupational assessments for the higher registered application rate of 0.14 lb ai/A (based on label EPA Reg. No. 81880

- 24) have never
been conducted. In addition, the highest application rate for field corn on one label ( EPA Reg.
No. 81880

- 20) has not been assessed and is the result of a typographical error. However, o n February 28, 20 12, th e registrant requested the voluntary cancellation of this product, and the Agency will process this cancellation through the Federal Register

. In light of the pending cancellation, this rate will not need to be assessed in registration review.

### Page 3 of 30 A new comprehensive human health risk assessment is not expected to be needed during registration review, unless t he results of the immunotoxicity study or changes in science and policy result in changes to toxicological endpoints

. Specifically, i n additi on , HED anticipates conducting a new risk assessment in July 2012 in conjunction with proposed new halosulfuron uses/tolerances under PRIA; this new assessment will entail new dietary and aggregate

assessment s and an occupational assessment of the proposed new uses.

I ntroduction

Halosulfuron

- methyl is a selective herbicide belonging to the sulfonylurea group of herbicides. It inhibits the action of the plant enzyme acetola c tate synthase . The enzyme is not found in
mammals (including humans)

. Halosulfuron

- methyl is used for the pre

- and postemergence control of annual broadleaf weeds and nutsedges in s elected crops, residential turf grass, and
ornamentals. Halosulfuron

- methyl is sold in the US as dry flowable/water

- dispersible granule
formulati on s or as emulsifiable concentrates

.

The most recent risk assessment for halosulfuron

- methyl was conducted in 2010 (D P# D 366410, W. Phang, 4/5/10). Refer to Attachment 1 (Tables 1 and 2) for chemical identity of parent and structures of parent and metabo lites.

Hazard Identification/ Toxicology

The toxicology database is adequate to support the existing tolera nces, with the exception of the requirement for an immunotoxicity study

. The immunotoxicity study is required under 40 CFR §1 58. 500 , and has been called in as a condition of registration (D366410, W. Phang, 4/5/10)

. The 28

- day inhalation toxicity study has been waived ( HASPOC Meeting , TXR # 0054045, DP#
D 397243, D. Smegal, MPH, 2/22/12)

. A point of departure (POD) derived from the oral toxicity

st udy data is sufficiently protective for risk assessment of potential maximum exposure via
inhalation. Th e weight of evidence approach that was used by HASPOC considered all of the available hazard and exposure information for halosulfuron

- methyl, includin g: (1) the use of an
oral point of departure ( POD ) that results in margins of exposure ( MOEs ) greater than 12,000 (the lowest MOE) for risk via the inhalation route resulting from occupational and residential exposures; (2) the physical/chemical properties and low volatility of halosulfuron

- methyl ; (3) the toxicological profile of halosulfuron

- methyl is limited to general systemic toxicity with no target organ toxicity; and (4) the low acute inhalation toxicity of halosulfuron

- methyl.

Halosulfuron

- methyl has low acute toxicity via the oral, dermal, and inhalation routes. It is a

non

- irritant for skin and eyes and is not a dermal sensitizer. With repeated dosing, halosulfuron produces non

- specific effects, which are frequently characterized by reduced body weight and body weight gains in the test animals. Carcinogenicity studies in rats and mice show no increase
in treatment

- related tumor in cidence, and it is classified as “not likely to be carcinogenic to
humans.” The results of both acute and subchronic neurotoxicity studies show no neurotoxic
effects. Halosulfuron

- methyl is negative for mutagenicity in a battery of genotoxicity studies.

Although the data indicated an increase in qualitative susceptibility in fetuses following prenatal exposure in rats and rabbits, the developmental effects were seen in the presence of maternal

### Page 4 of 30 effects and clear NOAELs (no observed adverse effect levels) and LOAELs (lowest observed adverse effect levels) were established for both maternal and developmental effects. In addition, the developmental effects in rats were seen at doses approaching the limit dose (1000 mg/kg /day ). It was concluded that the deg ree of concern was low and there was no residual uncertainty in either the rat or rabbit developmental toxicity study. The Food Quality Protection Act ( FQPA ) safety factor was reduced to 1X.

The points of departure (PODs) and toxicity endpoints from th e most recent risk assessment (D P# D 366410, W. Phang, 4/5/10) are summarized in Attachment 3 , Table 4 ( Dietary and Non

Occupational) and Table 5 (Occupational). The toxicity e ndpoints and POD s for risk

assessment were selected for the following exposure scenarios: acute and chronic dietary, short

and intermediate

- term incidental oral , dermal and inhalation

. Because of a common effect ( i.e., body weight gain changes ) seen in the studies selected for the endpoints for a ll three routes of exposure, MOE s an d exposures can be aggregated where appropriate.

Conclusions : The toxicology database is adequate, with the exception of the requirement for an immunotoxicity study

, w hich has been required as a condition of registration. D epending on the
results of the additional stud y , endpoints may need to be reevaluated and a new risk assessment

may be needed

.

Dietary Exposure

The most recent dietary exposure assessment (D P# D 367059, D. Rate, 3/4/10) w as conducted using the Dietary Exposure Evaluation Model DEEM

- FCIDTM, Version 2.03, which uses food consumption data from the US Department of Agriculture’s (USDA’s) Continuing Surveys of Food Intakes by Individuals (CSFII) from 1994

- 1996 and 1998. In the mo st recent risk assessment, unrefined a cute and chronic dietary (food and drinking water) exposure assessment s

w ere conducted for all food uses and drinking water. The residue levels used in the assessment s for all commodities were tolerance levels and t he assessment s w ere conducted using the assumption that 100% of the registered/proposed crop s w ere treated (100% CT). Default (DEEM 7.81) processing factors were used unless processing studies were available.

Estimated concentrations of halosulfuron

- meth yl in drinking water from use on rice, which reflected the highest use rate, were provided by the Environmental Fate and Effects Division (EFED) and incorporated directly into the acute and chronic assessment s . A Tier 1 drinking
water assessment for the u se on rice was performed using the FQPA Index Reservoir Screening Tool (FIRST) modeling. Estimate d drinking water concentrations (EDWCs) for halosulfuron

methyl are based on estimated surface water residues reflecting a maximum annual application
rate of 0.125 lb ai/A to rice. The acute estimated drinking water concentration (acute EDWC) of
halosulfuron

- methyl is not expected to exceed 59.2 ppb (0.0592 ppm). The annual mean (chronic) estimated drinking water concentration (chronic EDWC) of halosulfuron

- m ethyl is not expected to exceed 59.2 ppb (0.0592 ppm).

The acute and chronic dietary (food and drinking water) exposure s to halosulfuron

- methyl are below HED’s level of concern for the general US population and all population subgroups. For the general U S population, an appropriate dose/endpoint attributable to a single dose was not

### Page 5 of 30 observed in the reviewed oral toxicity studies. However, a toxicological endpoint attributable to a single dose of halosulfuron

- methyl was observed for the subgroup of f emale s 13

- 49 years old.
T he acute dietary exposure estimate at the 95 th 

### percentile is <1 % of the acute population adjusted dose ( aPAD ) for females 13

- 49 years old

. The chronic dietary exposure estimates are 2% of the chronic PAD ( cPAD ) for the general US population and 5% of the cPAD for all infants (<1 year old), the most highly exposed population subgroup.

HED classified halosulfuron

- methyl as “not likely to be a human carcinogen;” therefore, quantification of human cancer risk was n ot conducted.

The residue chemistry database is sufficient to support current registrations. The nature of the residue in plants and livestock ha s been defined, and adequate enforcement methods are available. Adequate storage stability, field trial, an d rotational crop data are available . 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, rotational crop tolerances and restrictions

are not r equir ed for halosulfuron

- methyl.

S ince the most recent risk assessment, a n amended registration (label amendment) to add post

emergent use on rice was submitted by Canyon Group LLC (agent Gowan Company) and has been reviewed ( D P# D 391400, S. Funk, 9/ 20 /11). S ixteen rice field trials and a rice processing study were submitted. The combination pre

- emergence and foliar postemergence use is already registered to another company (Helm Agro USA, Inc, EPA Registration No. 74530

- 321). Thus, the use pattern has been considered as part of previous human health risk assessments. No new tolerances are required in connecti o n with the petition. The existing tolerance for rice grain is adequate. However, HED is recommending that the established tolerance for halosulfuron

methyl in rice straw be revoked since rice straw is no longer considered a significant feed item in
the US. The recent action on rice does not increase the dietary burdens for ruminants or poultry.
The established livestock tolerances are ad equate.

Conclusions : A new risk assessment is not expected to be needed in the registration review

process. New risk assessments including new dietary exposure assessments will be conducted in
connection with a p ending PRIA action for new uses on pro so millet and Crop Group 17 (Grass Forage, Fodder, and Hay Group). In connection with the PRIA actions, t he dietary exposure assessment will be updated to the new version of DEEM (Version 3.04) , which may change dietary exposure estimates slightly as com pared to Version 2.03. The tolerance expression will be reviewed during registration review. T he chemical nomenclature for halosulfuron

- methyl in
the t olerance expression should be consistent with either the Chemical Abstracts Service (CAS)
nomenclature ( methyl 3

- chloro

- 5

- [[[[(4,6

- dimethoxy

- 2

- pyrimidinyl)amino]carbonyl]amino]sulfonyl]

- 1

- methyl

- 1 H

- pyrazole

- 4

- carboxylate) or the IUPAC nomenclature (methyl 3

- chloro

- 5

- (4,6

- dimethoxypyrimidin

- 2

- ylcar b amoylsulfamoyl )

- 1

- methylpyrazole

- 4

- carboxyl ate ).

### Page 6 of 30 Residential Exposure

Residential use patterns include residential turfgrass, ornamentals , and recreational turf areas. There is potential for short

- and intermediate

- term residential exposure to halosulfuron

- methyl during handling (mixing, loading, and a pplying) and post

- application activities.

For residential exposure, the durations of exposure are expected to be short

- term (1

- 30 days) and
intermediate

- term (1

- 6 months); long

- term exposures are not anticipated. The level of concern (LOC) for risk estim ates is a margin of exposure (MOE) of less than 100 for short

- and
intermediate

- term exposure.

Residential Handlers

Residential handlers are likely to be exposed to halosulfuron

- methyl residues via dermal and inhalation routes during handling activities. Specific potential residential handler scenarios were previously assessed for turfgrass at a maximum single application rate of 0.062 lb ai/A, and the calculated combined (dermal + inhalation) risk estimate for residential handlers was an MOE of 20,000 ( DP# D 278588

, K. O’Rourke , 8/28/2002). However, HED policies have since changed and new unit exposure values have been established. The most recent residential handler assessment was based on the HED Exposure Science Advisory Council (ExpoSAC) Residential Standard Operating Procedures (SOPs) and the Pesticide Handler Exposure Database (PHED)

, Version 1.1 unit exposures, as presented in the PHED Surrogate Exposure Guide (August 1998). Although there was no identified risk estimate of concern, an assessment for the higher registered application rate of 0.14 lb ai/A (based on label EPA Reg. No. 81880

- 24) has never
been conducted. Also, the tox icological endpoint s for short

- term dermal and short

- and
intermediate

- term inhalation exposure s were c hanged

.

Table 6 (Attachment 4 ) summarizes residential handler use patterns and corresponding MOEs.

Residential Post

- Application

Adults are likely to be exposed to halosulfuron

- methyl residues via the dermal route during post

application activities

. Young children are likely to be exposed to halosulfuron

- methyl via the dermal and oral routes during post

- application activities. Exposure risk estimates from lawn treatment were assessed for (1) adults and children’s post

- application dermal exposure, (2) children’s incidental ingestion of pesticide residues on lawns from hand

- to

- mouth transfer, (3) children’s object

- to

- mouth transfer from mouthing of pesticide

- treated turfgrass, and (4) children’s incidental ingestion of soil from pesticide

- treated reside ntial areas.

T here were no identified risk estimates of concern for young children with dermal and incidental oral MOEs rang ing from 1,100 to 3,200,000 and for adults with dermal MOEs ranging from 1,800 to 7,000. However, HED policies have since changed and new unit exposure values have been established. Furthermore, a higher registered application rate of 0.14 lb ai/A has never been
assessed. Also, the tox icological endpoint for short

- term dermal exposure was changed

.

### Page 7 of 30 Table 7 (Attachment 4 ) summarize s residential post

- application use patterns and corresponding
MOEs.

Conclusion s : There is sufficient information available to assess residential exposure. Although

a ll residential exposure scenarios have not been assessed using current ORE policy and current toxicological endpoints, a new residential assessment is not expected to be neede d in the registration review process. An updated residential exposure assessment will be conducted in connection with the pe nding PRIA action

.

Aggregate Risk Assessment

In the most recent human health risk assessment (D P# D 366410, W. Phang, 4/5/10), acute, short

term, and intermediate

- term aggregate exposures were assessed. A ggregate assessments considered exposures from food, drinking water, and residential uses. All risk estimates were
below the level of concern.

The chronic or long

- term aggregate risk assessment takes into account average exposure estimates from dietary consumption of halosulfuron

- methyl (food and drinking water) and
residential uses. Based on the halosulfuron

- methyl use pattern, no long

- term residential exposures are expected. Therefore, the chronic aggregate assessment includes only food and water and is equivalent to the chronic dietary assessment, for which the risk estimate is bel ow HED’s level of concern.

A cancer aggregate risk assessment was not performed because halosulfuron

- methyl has not been
shown to be carcinogenic.

Conclusion s : Since HED anticipates conducting a new risk assessment in 2012 in conjunction
with proposed new halosulfuron uses/tolerances under PRIA , t h e 2012 assessment may preclude
the need to conduct additional aggregate assessments for registration review.

HED expects to address the following issues in the new risk assessment in 2012: A new

agg regate as sessment may be needed depending on the results of the immunotoxicity study and the reevaluation of databases using current policies. A dditional toxicology studies are required so endpoints may need to be reevaluated. A new version of DEEM (Vers ion 3.04) will be used in dietary exposure assessments in the future, which may change dietary exposure estimates.
R esidential exposure assessments must be reassessed using current Occupational and Residential Exposure ( ORE ) policy , the revised toxicologi cal inhalation endpoint established in 2002, a nd
i nclud ing the highest application rates. In addition, the Agency may need to consider changes
that consider off

- target movement of pesticides into residential settings.

Occupational Exposure

Hal o sulfuron

- methyl is registered for several agricultural uses and for use in non

- crop areas. There is potential for short

- and intermediate

- term occupational exposure to halosulfuron

- methyl during handling (mixing, loading, and a pplying) and post

- application activities. Long

- term

### Page 8 of 30 exposures are not anticipated. The level of concern (LOC) for risk estimates is a margin of exposure (MOE) of less than 100 for short

- and intermediate

- term exposure.

Occupational Handlers

Previous occupational handler exposure and risk assessments were conducted for all of the agricultural crop use sites based on PHED. However, HED policies have since changed yielding updated acreage assumptions as well as updated unit exposure values. In addition, all assessments conducted prior to updated FQPA policies did not include any inhalation exposure
risk estimates. Also, the tox icological endpoint s for short

- term dermal and short

- and
intermediate

- term inhalation exposure s w ere changed

.

Exposu re and risk assessments have not been conducted for any of the registered non

- crop areas. The highest registered application rate to be assessed for non

- crop area occupational handler exposure is 0.14 lb ai/A (based on label EPA Reg. No. 81880

- 24).

Ta ble 8 (Attachment 5 ) lists the occupational handler scenarios for each use site and the corresponding MOEs, if previously assessed.

Occupational Post

- Application

Occupational post

- application exposure can occur via the dermal and/or inhalation route s

. S everal post

- application dermal exposures and risk estimates have been previously assessed, resulting in risk estimates which are not of concern (MOEs ranging from 560 to 83,000). HED policies have since changed, i.e., new unit exposure values and transfer coefficients (TCs) have
been established. However, an up

- to

- date occupational assessment is not expected to be needed during registration review as these changes are not expected to affect the risk conclusions of the previous assessment.

Table 9 (Attachment 5 ) summarizes the previously assessed occupational post

- application scenarios along with the corresponding MOEs . Based on the current assessments, the interim restricted entry interval (REI) of 12 hours is acceptable for all crops.

Based on t he Agency's current practices, a quantitative occupational post

- application inhalation

exposure assessment has not been performed for halosulfuron

- methyl at this time. However, there are multiple potential sources of post

- application inhalation exposure t o individuals performing post

- application activities in previously treated fields. These potential sources include volatilization of pesticides and resuspension of dusts and/or particulates that contain pesticides. The Agency sought expert advice and inp ut on issues related to volatilization of pesticides from its Federal Insecticide, Fungicide, and Rodenticide Act Scientific Advisory Panel (SAP) in December 2009. The Agency received the SAP’s final report on March 2, 2010 ( http://www.epa.gov/scipoly/SAP /meetings/2009/120109meeting.html ). The Agency is in the process of evaluating the SAP report as well as available post

- application inhalation exposure data generated by the Agricultural Reentry Task Force and may, as appropriate, develop policies and pro cedures to identify the need for and, subsequently, the way to incorporate occupational post

- application inhalation exposure into the Agency's risk assessments. If new policies or

### Page 9 of 30 procedures are put into place, the Agency may revisit the need for a quanti tative occupational post

- application inhalation exposure assessment for halosulfuron

- methyl.

Conclusion s : There is sufficient information available to assess occupational exposure. However, not all occupational exposure scenarios have been assessed u sin g current ORE policies and current toxicological endpoints

. HED does not anticipate conducting a n up

- to

- date occupational assessment as it does not expect changes in unit exposures and transfer coefficients to affect the risk conclusions of the previous assessment. If toxicological endpoint s change based on the p ending immuno to xicity study, then HED may revisit the need for an updated occupational assessment

.

Endocrine Disruptor Screening Program (EDSP)

As required by the Federal Insecticide, Fungicide, and Rodenticide Act ( FIFRA ) and the Federal Food, Drug, and Cosmetic Act ( FFDCA ) , EPA reviews numerous studies to assess potential adverse outcomes from exposure to chemicals. Collectively, these studies include acute, subchronic and chronic toxicity, including assessments of carcinogenicity, neurotoxicity, developmental, reproductive, and general or systemic toxicity. These studies include endpoints which may be susceptible to endocrine influence, includ ing effects on endocrine target organ histopathology, organ weights, estrus cyclicity, sexual maturation, fertility, pregnancy rates, reproductive loss, and sex ratios in offspring. For ecological hazard assessments, EPA evaluates
acute tests and chronic studies that assess growth, developmental and reproductive effects in different taxonomic groups. As part of its most recent registration decision

, EPA reviewed these data and selected the most sensitive endpoints for relevant risk assessment scenarios fr om the existing hazard database. However, as required by FFDCA section 408(p), halosulfuron

- methyl is subject to the endocrine screening part of the Endocrine Disruptor Screening Program (EDSP).

EPA has developed the EDSP to determine whether certain sub stances (including pesticide active and other ingredients) may have an effect in humans or wildlife similar to an effect produced by a “naturally occurring estrogen, or other such endocrine effects as the Administrator may designate.” The EDSP employs a t wo

- tiered approach to making the statutorily required determinations. Tier 1 consists of a battery of 11 screening assays to identify the potential of a chemical substance to interact with the estrogen, androgen, or thyroid (E, A, or T) hormonal systems. Chemicals that go through Tier 1 screening and are found to have the potential to interact with E, A, or T hormonal systems will proceed to the next stage of the EDSP where EPA will determine which, if any, of the Tier 2 tests are necessary based on the av ailable data. Tier 2 testing is designed to identify any adverse endocrine

- related effects caused by the substance, and
establish a dose

- response relationship between the dose and the E, A, or T effect.

Under FFDCA section 408(p), the Agency must screen all pesticide chemicals. Between October 2009 and February 2010, EPA issued test orders/data call

- ins for the first group of 67 chemicals, which contains 58 pesticide active ingredients and 9 inert ingredients. Halosulfuron

methyl is not among the group of 58 pesticide active ingredients on the initial list to be screened under the EDSP. Accordingly, as part of registration review, EPA will issue future EDSP
orders/data call

- ins, requiring the submission of EDSP screening assays for halosulfuron

- methyl. For further information on the status of the EDSP, the policies and procedures, the list of 67

### Page 10 of 30 chemicals, future lists, the test guidelines and the Tier 1 screening battery, please visit our
website: http://www.epa.gov/endo/

.

Public Health and Pesticide Epidemiology Data

The evaluation of the OPP Incident Data System (IDS) indicated that no incidents were identified in the Uni ted States from January 1, 2006 through November 2, 2011 for the single
che mical halosul furon

- methyl (DP# D395323, S. Recore, 12/8/11) . In Aggregate IDS from January 1, 2006 to November 2, 2011, there are 14 incidents reported for halosulfuron

- methyl. Because it falls within the categories reported as counts (which includes min or, unknown or no effects), there is no unique report that provides details about the incident and single chemical incidents are not distinguished from multiple chemical incidents; however, a high frequency of incidents indicates there is a high potential for exposure and vice versa. For halosulfuron

methyl, there appears to be a low potential for exposure. Halosulfuron

- methyl is not included in the Agricultural Health Study (AHS), and therefore, the AHS does not provide information for this report. Base d on the low frequency and severity of incident cases for halosulfuron

- methyl,

t here does not appear to be a concern at this time that would warrant further investigation. The Agency will continue to monitor the incident information . I f a concern is trig gered, additional analysis will be included in the risk assessment.

Tolerance Assessment and International Harmonization

Permanent US tolerances are established under 40 CFR §180.479(a)(1) for residues of the
herbicide halosulfuron

- methyl , methyl 5

- [(4,6

- dimethoxy

- 2

- pyrimidinyl)amino]carbonylaminosulfonyl]

- 3

- chloro

- 1

- methyl

- 1 H

- pyrazole

- 4

- carboxylate, including its metabolites and degradates , in/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 res id ues containing the 3

- chlorosulfonamide (3

- CSA) moiety, expressed as the stoichiometric equivalent of halosulfuron

- methyl.

Perm ane nt US t olerances are established under 4 0 CFR §180.479(a)(2) for residues of the
herbicide halosulfuron

- methyl, methyl 5

- [(4,6

- dimethoxy

- 2

- pyrimidinyl)amino]carbonylaminosulfonyl]

- 3

- chloro

- 1

- methyl

- 1 H

- pyrazole

- 4

- carboxylate, including its metabolites and degradates, i n/on a variety of field, fru it, 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.

There are no Codex, Canadian, or Mexican maximum residue limits ( MRLs ) es tablish ed for
residues of halosulfuron

- methyl in crop or livestock commodities (see Attachment 2 , Table 3 )

. The US tolerance expression will be reviewed during registration review since the chemical
nomenclature for halosulfuron

- methyl in the tolerance exp ression should be consistent with
either the CAS or IUPAC nomenclature.

### Page 11 of 30 Environmental Justice

Potential areas of environmental justice concerns, to the extent possible , w ill be considered in th e registration review , in accordance with US Executive Order 12898 , "Federal Actions to Address Environmental Justice in Minority Populations and Low

- Income Populations," http://www.eh.doe.gov/oepa/guidance/justice/eo12898.pdf ).

As a part o f every pesticide risk assessment, OPP considers a large variety of consumer subgroups according to well

- established procedures. In line with OPP policy, HED estimates risks to population subgroups from pesticide exposures that are based on patterns of th at subgroup’s food and water consumption, and activities in and around the home that involve pesticide use in a residential setting. Extensive data on food consumption patterns are compiled by the USDA under the Continuing Survey of Food Intake by Individ uals (CSFII) and are used in pesticide risk assessments for all registered food uses of a pesticide. These data are analyzed and categorized by subgroups based on age, season of the year, ethnic group, and region of the country. Additionally, OPP is able to assess dietary exposure to smaller, specialized subgroups and exposure assessments are performed when conditions or circumstances warrant. Whenever appropriate, non

- dietary exposures based on home use of pesticide products and associated risks
for adu lt applicators and for toddlers, youths, and adults entering or playing on treated areas postapplication are evaluated. Further considerations are currently in development as OPP has committed resources and expertise to the development of specialized soft ware and models that consider exposure to bystanders and farm workers as well as lifestyle and traditional dietary patterns among specific subgroups

.

Cumulative

Unlike other pesticides for which EPA has followed a cumulative risk approach based on a

co mmon mechanism of toxicity, EPA has not made a common mechanism of toxicity finding as

to halosulfuron

- methyl and any other substances and halosulfuron

- methyl does not appear to produce a toxic metabolite produced by other substances. For information rega rding EPA’s efforts to determine which chemicals have a common mechanism of toxicity and to evaluate the cumulative effects of such chemicals, see the policy statements released by EPA’s Office of Pesticide Programs concerning common mechanism determinatio ns and procedures for cumulating effects from substances found to have a common mechanism on EPA’s website at http://www.epa.gov/pesticides/cumulative/.

Human Studies

Past halosulfuron

- methyl risk assessments rely in part on data from studies in which adult human subjects were intentionally exposed to a pesticide to determine their dermal and inhalation exposure. Many such studies, involving exposure to many different pesticides, comprise generic

p esticide exposure databases such as the Pesticide Ha ndlers Exposure Database (PHED), the Outdoor Residential Exposure Task Force (ORETF), and the Agricultural Reentry Task Force (ARTF) Database

. EPA has reviewed all the studies supporting these multi

- pesticide generic exposure databases, and has found no clear and convincing evidence that the conduct of any of them was either fundamentally unethical or significantly deficient relative to the ethi cal

### Page 12 of 30 standards prevailing at the time the research was conducted. A ll applicable requirements of EPA’s Rule for the Protection of Human Subjects of Research (40 CFR Part 26) have been
satisfied , and t here is no regulatory barrier to continued reliance on t hese studies

.

Data Requirements

As shown in Reference s below, s even human health risk assessments have been conducted for
halosulfuron

- methyl between 1999 and 20 10. A recent Section 3 petition for a label amendment

on rice has been reviewed. As shown i n detail in Attachment 6 , t here are outstanding data gaps
associated with the Section 3 assessments

, including a requirement for an immunotoxicity study and the requirement that an analytical reference standard for the rearrangement ester ( RRE ) of
halosulf uron

- methyl be submitted to the EPA National Pesticide Standards Repository

.

References

Memoranda Relevant to Registration Review of Halosulfuron

- methyl
Author Barcode (DP#) Date Title

Risk Assessments
S. Weiss D251257 2/9/99 PP#6F4661 & PP#8F4937. Human Health Risk Assessment for
Halosulfuron

- methyl: New Uses on Sweet Corn, Popcorn, Cotton,
Tree

- nuts, and Rice; and Revised Tolerances on Field Corn, Grain Sorghum, and Sugar Cane

M. Rust D261708 6/29/00 HED Risk Assess ment : Human Health Risk Assessment for
Halosulfuron

- methyl to be used on Subgroup 9B Crops (Squash/Cucumber Subgroup)

M. Rust D271574 10/16/01 H ED Risk Assessment: Human Health Risk Assessment for
Halosulfuron

- methyl to Support Request for New Use in/on Melons (Crop Subgroup 9A)

M. Rust D278447 9/4/02 HED Risk Asses sment: Human Health Risk Assessment for
Halosulfuron

- methyl to Support Request for New Use in/on Fruiting Vegetables (Crop Group 8), Dry Beans and Snap Beans
M. Clock

Rust D331643 9/21/06 Halosulfuron

- methyl: Human Health Risk Assessment for Proposed
Uses on Alfalfa W. Phang D358031 6/30/09 Halosulfuron

- methyl: Human Health Risk Assessment for Proposed Uses on Soybean W. Phang D366410 4/5/10 Halosulfuron

- Methyl: Human Health Risk Assessment for IR

- 4 Proposed Uses on C rop Group 6B Succulent Shelled Pea and Bean Subgroup, Crop Group 1C Tuberous and Corn Vegetables Subgroup, Crop Group 6C Dried Shelled Pea and Bean (Except Soybean), Subgroup 13

- 07B Bushberry, Okra, Apples, and Rhubarb

Residue Chemistry
G. J. Herndon D173627 7/30/92 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.
G. J. Herndon D189189 3/7/94 Permanent Tolerance Request for Use of MON 12000 (Halosulfuron) on Field Corn and Grain Sorghum (Milo). Evaluation of Analytical
Method and Residue Data.
A. Acierto D271686 5/16/01 PP# 0E6206. Halosulfuron

- methyl On Melon Sub group. Review of Analytical Methods and Magnitude of Residue Data.
N. Dodd D358029 4/23/09 Halosulfuron

- methyl. Application for Amended Section 3

### Page 13 of 30 Memoranda Relevant to Registration Review of Halosulfuron

- methyl
Author Barcode (DP#) Date Title

Registration to Add Uses on Soybeans. Summary of Analytical Chemistry and Residue Data.

D. Rate D367058 3/3/10 Halosulfuron

- methyl. Application for Section 3 Registration of Sandea® Herbicide (EPA Reg. No. 81880

- 18) and GWN

- 3061 Herbicide (EPA Reg. No. 81880

- 2) t o 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.
S. Funk D391400 9/ 20 /11 H H alosulfuron

- methyl. Application for Section 3 Registration of Permit PlusTM Herbicide (EPA Reg. No. 81880

- 26) t o Add a New Use on Rice. Summary of Analytical Chemistry and Residue Data. Dietary Exposure Assessment
D. Rate D367059 3/4/10 H H alosulfuron

- methyl Acute and Chronic Aggregate Dietary (Food and Drinking Water) Exposure and Risk Assessments for the Section 3 Registration Action on Pea and Bean, Succulent Shelled, Subgroup 6B; Vegetable, Tuberous and Corm, Subgroup 1C; Rhubarb;
Bushbe rry Subgroup 13

- 07B; Apple; and Okra. Occupational Residential Exposure
G. J. Herndon D223266 7/22/98 Halosulfuron. Label Amendment to Increase Application Rates on Grain Sorghum (Milo)

M. Rust D265726 6/21/00 Occupational and Residential Risk Assessment to Support Request for
New Uses of Halosulfuron

- methyl on Vegetables in the Cucumber and Squash Subgroup (Subgroup 9B)
J. Arthur D273929 4 /2 0 /01 Occupational and Residential Risk Assessment to Support Request for
New Uses of Halosulfuron

- methyl on Vegetables in the Cucumber and Squash Subgroup (Subgroup 9B)
J. Arthur D271574 9/1 7 /01 H alosulfuron

- methyl : Occupational and Residential Risk Assessment to Support Request for Use on Melons.
K. O’Rourke D278588 8/28/02 H alosulfuron

- methyl: Occupational and Residential Risk Assessment to Support Request for Use on Dry Beans, Snap Beans, Asparagus, and Fruiting Vegetables.
K. O’Rourke D331645 8/29/06 H alosulfuron

- methyl : Occupational and Residential Risk Assessment to Sup port Request for Use on Alfalfa.
B. O’Keefe D359456 4/27/09 Halosulfuron

- methyl : Occupational and Residential Exposure
Assessment for proposed field use of halosulfuron

- methyl on soybeans.

N. Tsaur D367060 3/4/10 Halosulfuron

- m ethyl

. Occupational and Residential Exposure
Assessment f or Proposed Field Use of Halosulfuron

- Methyl on Succulent Shelled Peas and Beans (Subgroup 6B), Tuberous and Corm Vegetables (Subgroup 1C), Rhubarb, Bushberry (Subgroup 13

- 07B), Dried Shelled Peas and Beans (Except Soybean, Subgroup 6C), Apples, and Okra.

N. Tsaur D 393885 10/13/11 Halosulfuron

- methyl. Occupational and Residential Exposure Assessment for a Proposed Addition of Post

- Emergent Weed Control
Use on Rice. Toxicology
S. Recore D395323 12/8/11 Halosulfuron

- methyl: Review of Human Incidents D. Smegal D397243 2/22/12 Halosulfuron

- methyl: Summary of Hazard and Science Policy Council (HASPOC) Meeting of February 9, 2012: Recommendations
on waiver requests for 28

- day inhalation study.

### Page 14 of 30 Attachment s 1. Chemical Identity Table s 2. Tolerance Summary Table
3 . Endpoint Selection Table
4 . Residential Exposure Tables
5 . Occupational Exposure Tables
6 . Outstanding Deficiencies to be Addressed by the Registrants

### Page 15 of 30 Attachment 1 Chemical Identity Table s

Table 1. Chemical Identity

– Halosulfuron

- methyl
Common Name halosulfuron

- methyl Chemical Name (CAS) methyl 3

- chloro

- 5

- [[[[(4,6

- dimethoxy

- 2

- pyrimidinyl)amino]carbonyl]amino]sulfonyl]

- 1

- methyl

- 1 H

- pyrazole

- 4

- carboxylate
PC Code 128721
Chemical Abstracts No. 100784

- 20

- 1 Registration Review Case No. NA
Chemical Class sulfonylurea
Chemical Structure

Table 2 . Structures of Metabolites

Chemical structure of
3

- chlorosulfonamide moiety (3

- CSA)

3

- chloro

- 1

- methyl

- 5

- sulfamoyl

1 H

- pyrazole

- 4

- carboxylic acid

Rearrangement ester (RRE) of
halosulfuron

- methyl N N

C H 3 Cl

N N N H N H

O S

O O

O C H 3 O C H 3 O

O C H 3

N N

C H 3 Cl

N H 2 S

O O O H O

N

N O C H 3

O

C H 3 N H N N

C H 3 Cl O

O C H 3

### Page 16 of 30 Attachment 2
Tolerance /MRL Table

As shown in the table below, t here are no Codex, Canadian, or Mexican maximum residue limits (MRLs) established for residues of halosulfuron

- methy l in crop or livestock commodities.

Halosulfuron

- methyl (128721; 10/03/2011)

Table 3

. Summary of US and International Tolerances and Maximum Residue Limits Residue Definition : US Canada Mexico Codex 1 2

40 CFR § 180.479 (a) (1) : Tolerances are established for residues
of the herbicide halosulfuron

- methyl, methyl 5

- [(4,6

- dimethoxy

2

- pyrimidiny)amino] carbonylaminosulfonyl]

- 3

- chloro

- 1

- methyl

1 H

- pyrazole

- 4

- carboxylate, including its metabolites and degradates, in or on the commodities in the following table. Compliance with the tolerance levels specified in the following table is to be determined by measuring only those halosulfuron

methyl residu es containing the 3

- chlorosulfonamide (3

- CSA) moiety, expressed as the stoichiometric equivalent of
halosulfuron

- methyl

. None None

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

US Canada Mexico Codex 1 2 Cattle, meat byproducts 0.1 Goat, meat byproducts 0.1
Hog, meat byproducts 0.1 Horse, meat byproducts 0.1 Sheep, meat byproducts 0.1

US Canada Mexico Codex 1 2
40 CFR §180.479(a)(2) : Tolerances are established for residues
of the herbicide halosulfuron

- methyl, methyl 5

- [(4,6

- dimethoxy

2

- pyrimidiny)amino]carbonylaminosulfonyl]

- 3

- chloro

- 1

- methyl

1 H

- pyrazole

- 4

- carboxylate, including its metabolites and degradates, in or on the commodities in the following table. Compliance with the tolerance levels specified in the following table is to be determined by measuring only halosulfuron

- methyl

. None None

Commodity Tolerance (ppm) /Maximum Residue Limit (mg/kg)
US Canada Mexico Codex 1 2 Alfalfa, forage 1.0 Alfalfa, hay 2.0 Almond, hulls 0.2 Apple 0.05 Asparagus 0.8 Bean, dry, seed 0.05 Bushberry, subgroup 13

- 07B 0.05 Corn, field, forage 0.2 Corn, field, grain 0.05 Corn, field, stover 0.8 Corn, pop, grain 0.05 Corn, pop, stover 0.8 Corn, sweet, forag e 0.2

### Page 17 of 30 Table 3

. Summary of US and International Tolerances and Maximum Residue Limits Residue Definition : US Canada Mexico Codex 1 2
Corn, sweet, kernel plus cob with
husks removed 0.05

Corn, sweet, stover 0.8 Cotton, gin byproducts 0.05 Cotton, undelinted seed 0.05 Melon subgroup 9A 0.1 Nut, tree, group 14 0.05
Okra 0.05 Pea and bean, succulent shelled, subgroup 6 0.05

Pea and bean, succulent shelled, subgroup 6B 0.05

Pistachio 0.05
Rhubarb 0.05 Rice, grain 0.05 Rice, straw 0.2 Sorghum, grain, forage 0.05 Sorghum, grain, grain 0.05 Sorghum, grain, stover 0.1 Soybean, seed 0.05 Squash/Cucumber subgroup 9B 0.5 Sugarcane, cane 0.05 Vegetable, fruiting, group 8 0.05 Vegetable, tuberous and corm, subgroup 1C 0.05

Completed by: M. Negussie; 10/05/2011

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

2 * = 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 t he sample. MRLs indicated as proposed have not been finalized by the CCPR and the CAC.

### Page 18 of 30 Attachment 3

Summary of Toxic ity Endpoints and Points of Departure of Halosulfuron

- methyl

Table 4

. Toxicological Doses and Endpoints for Halosulfuron

- Methyl for Dietary and Non

- Occupational
Human Health Risk Assessments. Exposure/
Scenario Point of Departure Uncertainty/ FQPA Safety
Factors RfD, PAD,
Level of
Concern for
Risk
Assessment Study and Toxicological Effects

Acute Dietary (Females 13

- 49 years of age) NOAEL=
50 mg/kg/day UF A = 10x
UF H = 10x FQPA SF= 1x Acute RfD = 0.5 mg/kg/day

aPAD =0.5 mg/kg/day Developmental Toxicity

- Rabbit LOAEL = 150 mg/kg/day based on decreased mean litter size, increased number of resorptions (total and per dam) and increased

po stimplantation loss (developmental toxicity). Acute Dietary (General Population including Infants and Children) N/A N/A N/A No adverse effect attributable to a single dose was identified; therefore, no dose/endpoint was selected for this exposure scenario.

Chronic Dietary (All Populations) NOAEL=
10 mg/kg/day UF A = 10x
UF H = 10x FQPA SF= 1x Chronic RfD =
0.1 mg/kg/day

cPAD = 0.1 mg/kg/day Chronic Toxicity

- Dog LOAEL = 40 mg/kg/day based on decreased body weight gains in females.

Incidental Oral
Short

- Term (1

- 30 days) NOAEL=
50 mg/kg/day UF A = 10x
UF H = 10x FQPA SF= 1x Residential LOC
for MOE = 100 Developmental Toxicity

- Rabbit LOAEL = 150 mg/kg/day based on decreased body weight gain, food consumption, and food efficiency (maternal toxicity).
Incidental Oral
Intermediate

Term (1

- 6 months) NOAEL=
10 mg/kg/day UF A = 10x
UF H = 10x FQPA SF= 1x Residential LOC
for MOE = 100 13 Week Subchronic Toxicity

- Dog LOAEL = 40 mg/kg/day based on decreased body weight gains and food efficiency along
with hematological and clinical chemistry changes.
Dermal Short

Term (1

- 30 days) NOAEL=
100 mg/kg/day UF A = 10x
UF H = 10x FQPA SF= 1x Residential LOC
for MOE = 100 21

- Day Dermal Toxicity Study

- Rat LOAEL = 1000 mg/kg/day based on decreased body weight gain in males.
Dermal
Intermediate

Term (1

- 6 months) NOAEL=10 mg/kg/day

+ UF A = 10x
UF H = 10x FQPA SF= 1x Residential LOC
for MOE = 100 13 Week Subchronic Toxicity

- Dog LOAEL = 40 mg/kg/day based on decreased body weight gains and food efficiency along
with hematological and clinical chemistry changes.
Inhalation
Short

- Term (1

- 30 days) NOAEL =
50 mg/kg/day UF A = 10x
UF H = 10x FQPA SF= 1x Residential LOC
for MOE = 100 Developmental Toxicity

- Rabbit LOAEL = 150 mg/kg/day based on decreased body weight gain, f ood consumption, and food efficiency (maternal toxicity).
Inhalation
Intermediate

Term (1

- 6 months) NOAEL=
10 mg/kg/day UF A = 10x
UF H = 10x FQPA SF= 1x Residential LOC
for MOE = 100 13 Week Subchronic Toxicity

- Dog LOAEL = 40 mg/kg/day based on decreased body weight gains and food efficiency along with hematological and clinical chemistry changes.

### Page 19 of 30 Table 4

. Toxicological Doses and Endpoints for Halosulfuron

- Methyl for Dietary and Non

- Occupational
Human Health Risk Assessments. Exposure/
Scenario Point of Departure Uncertainty/ FQPA Safety
Factors RfD, PAD,
Level of
Concern for
Risk
Assessment Study and Toxicological Effects

C ancer Classification: "not likely to be carcinogenic to humans" by the oral route, based on no evidence of carcinogenicity from studies in rats and mice.

+

NOAEL = no observed adverse effect level. L OAEL = lowest observed adverse effect level. UF = uncertainty
factor. UF A = extrapolation from animal to human ( inter

- species ). UF H = potential variation in sensitivity among members of the human population ( intra

- species ). FQPA SF = FQPA Safety Factor. PAD = population adjusted dose (a = acute, c = chronic). RfD = reference dose. MOE = margin of exposure. LOC = level of concern. N/A = not applicable.

A 75% dermal absorption factor should be used in route

- to

- route extrapolation for the intermediate term dermal exposure risk. Absorption via the inhalation route is presumed to be equivalent to oral absorption.

Table 5

. Summary of Toxicological Doses and Endpoints for Halo sulfuron

- Methyl for Occupational Human
Health Risk Assessments. Exposure/
Scenario Point of Departure (mg/kg/day) Uncertainty
Factors Level of Concern
for Risk
Assessment Study and Toxicological Effects

Dermal Short

Term (1

- 30 days) NOAEL=
100 UF A = 10x
UF H = 10x Occupational LOC
for MOE = 100 21

- Day Dermal Toxicity Study

- Rat LOAEL = 1000 mg/kg/day based on decreased body weight gain in males.
Dermal
Intermediate

Term (1

- 6 months) NOAEL=10

+ UF A = 10x
UF H = 10x Occupational LOC
for MOE = 100 13 Week Subchronic Toxicity

- Dog LOAEL = 40 mg/kg/day based on decreased body weight gains and food efficiency along with hematological and clinical chemistry changes.
Inhalation
Short

- Term (1

- 30 days) NOAEL=50 UF A = 10x
UF H = 10x Occupational LOC
for MOE = 100 Developmental Toxicity

– Rabbit LOAEL = 150 mg/kg/day based on decreased body weight gain, food consumption, and food efficiency (maternal toxicity).
Inhalation
Intermediate

term (1

- 6 months) NOAEL=
10 UF A = 10x
UF H = 10x Occupational LOC
for MOE = 10 0 13 Week Subchronic Toxicity

- Dog LOAEL = 40 mg/kg/day based on decreased body weight gains and food efficiency along with hematological and clinical chemistry changes.
Cancer Classification: "not likely to be carcinogenic to humans " by the oral route, based on no evidence of carcinogenicity from studies in rats and mice.

+

NOAEL = no observed adverse effect level. LOAEL = lowest observed adverse effect level. UF = uncertainty
factor. UF A = extrapolation from animal to human ( intra

- species ). UF H = potential variation in sensitivity am ong members of the human population ( inter

- species ). MOE = margin of exposure. LOC = level of concern.

A 75% dermal absorption factor should be used in route

- to

- route extrapolation for the intermediate term dermal exposure risk. Absorption via the inhalation route is presume d to be equivalent to oral absorption.

### Page 20 of 30 Attachment 4

Residential Exposure Tables

Table 6

. Summary of Residential Use Patterns, Formulations, and Application Rates for Halosulfuron

Methyl. Registered

Product Formulation 1 Application Equipment Use Sites Maximum Application Rate Combined
MOE 2 DP#
Reference EPA Reg. No. % ai by weight lb ai/A
228

- 702 WDG 75%

Handheld Sprayers Commercial, Industrial,
Residential
Areas 0.125

--- NA 3

228

- 711 WDG 75% 0.125

--- NA 3

2749

- 528 WDG 75% 0.125

--- NA 3

74530

- 34 WDG 75% 0.0625 20,000 278588

81880

- 1 WDG 75% 0.125

--- NA 3

81880

- 6 WDG 12.5% 0.0625 20,000 278588

81880

- 14 WDG 75% 0.0625 20,000 278588

81880

- 17 WDG 75% 0.11

--- NA 3

81880

- 19 WDG 75% 0.0625 20,000 278588

81880

- 22 WDG 75% 0.0625 20,000 278588

81880

- 23 WDG 10% 0.0625 20,000 278588
81880

- 24 WDG 5% 0.14

--- NA 3

81880

- 26 WDG 66.2% 0.0621 covered 278588

1 WDG = water

- dispersible granular.

2

--- = not assessed. Covered = Previous assessment is protective of this use pattern and application rate.

3 Not applicable.

Table 7

. Residential Post

- Application Exposure Scenarios for Halosulfuron

- Methyl.

Pest /Use Site Application Equipment Formulation Type(s) 1 Registered Application Rate Post

- Application MOEs 2 DP
Barcode lb ai/A

Commercial,

Industrial,
Residential Areas Handheld Sprayers WDG 0.0625 Adults: ST: 7,000 IT: 1,800 278588

Children: ST: 3,200,000 IT: 1,100 278588

0.0621 covered 278588

0.11

--- NA 3

0.125

--- NA 3

0.14

--- NA 3

1 WDG = water

- dispersible granular.

2

--- = not assessed. Covered = Previous assessment is protective of this use pattern and application rate.

### Page 21 of 30 Attachment 5

Occupational Exposure Tables

Table 8. Occupational Exposure Scenarios for Halosulfuron

- Methyl. 1

Crop/Use Site Application Equipment Formulation 2 Maximum Registered Application
Rate
lb ai/ A Scenario Combined MOE 3

Mixer/

Loader Applicator Flagger 4 DP

Barcode

Agricultural Uses

– RACs

Alfalfa g round WDG 0.047 ST: 11,000 IT: 1,500 ST: 48,000 IT: 6,600 --- 331645

aerial WDG 0.047 ST: 1,800
IT: 250 ST: 24,000 IT: 3,300 --- 331645

Apple ground WDG 0.094 ST: 14,000 IT: 1,900 ST: 60,000 IT: 8,300 --- 367060

handheld WDG 0.094 ST: 4,800
IT: 650 --- 367060

aerial WDG 0.094

--- --- --- ---

airblast WDG 0.094

--- --- --- ---

Asparagus ground WDG 0.07 ST: 11,000 IT: 2,100 ST: 51,000 IT: 10,000 --- 273929

backpack WDG 0.07 ST: 640
IT: 130 --- 273929

aerial WDG 0.07

--- --- --- ---

Bushberry (Subgroup 13B) g round WDG 0.047 ST: 28,000 IT: 3,700 ST: 120,000 IT: 17,000 --- 367060

handheld WDG 0.047 ST: 9,300 IT: 1,300 --- 367060

aerial WDG 0.047

--- --- --- ---

airblast WDG 0.047

--- --- --- ---

Corn (Field) ground WDG 0.063 ST 5 , 600
IT 1 , 100 ST 26,000 IT 5,300 --- 265726

aerial WDG 0.0 63 ST 940
IT 190 ST 12,000 IT 2,400 --- 265726

soil WDG 0.47

--- --- --- ---

Corn (Sweet, Pop) ground WDG 0.063 ST: 12,000 IT: 2,400 ST: 56,000 IT: 11,000 --- 251257

a erial WDG 0.063 ST: 2,800
IT: 560 ST: 36,000 IT: 16,000 --- 251257

Cotton ground WDG 0.0625 ST: 12,000 IT: 2,400 ST: 56,000 IT: 11,000 --- 251257

backpack WDG 0.0625 ST: 2,800
IT: 560 ST: 36,000 IT: 16,000 --- 251257

aerial WDG 0.0625

--- --- --- ---

### Page 22 of 30 Table 8. Occupational Exposure Scenarios for Halosulfuron

- Methyl. 1

Crop/Use Site Application Equipment Formulation 2 Maximum Registered Application
Rate
lb ai/ A Scenario Combined MOE 3

Mixer/

Loader Applicator Flagger 4 DP

Barcode

Nut, Tree (Crop Group 14) ground WDG 0.063 ST: 12,000 IT: 2,400 ST: 56,000 IT: 11,000 --- 251257

a erial WDG 0.063 ST: 2,800
IT: 560 ST: 36,000 IT: 16,000 --- 251257

airblast WDG 0.063

--- --- --- ---

Okra ground WDG 0.047 ST: 28,000
IT: 3,700 ST: 120,000 IT: 17,000 --- 367060

handheld WDG 0.047 ST: 9,300 IT: 1,300 --- 367060

aerial WDG 0.047

--- --- --- ---

airblast WDG 0.047

--- --- --- ---

Pea and Bean, Dried Shelled, Except Soybean (Subgroup 6C) ground WDG 0.047 ST: 28,000
IT: 3,700 ST: 120,000 IT: 17,000 --- 367060

handheld WDG 0.047 ST: 9,300 IT: 1,300 --- 367060

aerial WDG 0.047

--- --- --- --- Pea and Bean,

Succulent

Shelled (Subgroup 6B) ground WDG 0.023 ST: 56,000 IT: 7,600 ST: 250,000 IT: 34,000 --- 367060

aerial WDG 0.023

--- --- --- ---

Rhubarb ground WDG 0.047 ST: 28,000 IT: 3,700 ST: 120,000 IT: 17,000 --- 367060

handheld WDG 0.047 ST: 9,300 IT: 1,300 --- 367060

aerial WDG 0.047

--- --- --- ---

Rice ground WDG 0.063 ST: 12,000 IT: 2,400 ST: 56,000
IT: 11,000 --- 251257

a erial WDG 0.063 ST: 2,800
IT: 560 ST: 36,000 IT: 16,000 --- 251257

Sorghum, Grain (Milo) ground WDG 0.047 ST: 110,000 IT: 22,000 ST: 76,000 IT: 15,000 --- 223266

aerial WDG 0.047

--- --- --- ---

Soybean ground WDG 0.062 ST: 8,400 IT: 1,100 ST: 36,000 IT: 5,000 --- 359456

aerial WDG 0.062 ST: 1,400
IT: 190 ST: 18,000 IT: 2,500 ST: 28,000
IT: 3,800 359456

Sugarcane ground WDG 0.063 ST: 12,000 IT: 2,400 ST: 56,000 IT: 11,000 --- 251257

a erial WDG 0.063 ST: 2,800
IT: 560 ST: 36,000 IT: 16,000 --- 251257

Vegetable,

Cucurbit ground WDG 0.047 ST: 26,000 IT: 3,600 ST: 120,000 IT: 16,000 --- 278588

### Page 23 of 30 Table 8. Occupational Exposure Scenarios for Halosulfuron

- Methyl. 1

Crop/Use Site Application Equipment Formulation 2 Maximum Registered Application
Rate
lb ai/ A Scenario Combined MOE 3

Mixer/

Loader Applicator Flagger 4 DP

Barcode
(Crop Group 9) aerial WDG 0.047

--- --- --- ---

Vegetable,

Fruiting (Crop Group 8) ground WDG 0.047 ST: 26,000 IT: 3,600 ST: 120,000 IT: 16,000 --- 278588

aerial WDG 0.047

--- --- --- --- Vegetable,
Tuberous and
Corm (Subgroup 1C) ground WDG 0.047 ST: 28,000 IT: 3,700 ST: 120,000 IT: 17,000 --- 367060

aerial WDG 0.047

--- --- --- ---

Non

- Agricultural Uses

Non

- Crop Areas ( airports, cemeteries,
fallow non

- crop areas, golf

courses, landscaped areas, public recreation areas, residential property, roadsides, school grounds, sod or turf seed farms,

sports fields,
residential and

commercial landscaped areas
with established woody ornamentals, fairgrounds, race

tracks, tennis
courts, campgrounds and rights

- of way) Garden
Hose WDG 0.062 ST: 20,000

--- 278588

Roadsides, Rights

- of

- Way, Tank Farms, Lumberyards, Fuel Storage Areas, Fallow Land, Fence
Rows Handheld WDG 0.14

--- --- ---

### Page 24 of 30 Table 8. Occupational Exposure Scenarios for Halosulfuron

- Methyl. 1

Crop/Use Site Application Equipment Formulation 2 Maximum Registered Application
Rate
lb ai/ A Scenario Combined MOE 3

Mixer/

Loader Applicator Flagger 4 DP

Barcode Turfgrass, Ornamentals,
Fallow Ground Handheld WDG 0.14

--- --- ---

1 The tox icological endpoint for short

- term dermal exposure was changed since some calculations were done; calculations done
before the tox icological endpoint was revised must be redone.

2 WDG = water dispersible granule.

3 MOE = margin of exposure.

--- = not assessed. Bold numbers indicate that calculations do not include inhalation exposure

(only dermal). Handheld equipment calculations are based on mixer/loader/applicator scenarios with glove PPE mitigation. Aerial equipment calculations are based on closed cab engineering control mitigation. Other scenarios calculated at baseline

. 4 Aerial applications are not shaded.

### Page 25 of 30 Table 9

. Occupation al Post

- Application Exposure Scenarios for Halosulfuron

- Methyl.

Use Site
(TC Group) Activity Current
Dermal

TC Assessed
TC 1 DFR 2 Dermal
MOE 3 DP
Barcode 4

Alfalfa (field/row crops, low/medium) irrigation 1,900 1,500 0.11 ST: 5,500
IT: 740 331645 scouting 1,100 100 0.11 ST: 83,000 IT: 11,000

Apple (trees, fruit, deciduous) thinning 3,600

--- --- --- --- hand harvesting 1,400

scouting, hand pruning, training 580

transplanting 230

hand weeding, propping,

orchard maintenance 100

Asparagus (vegetables, stem/stalk) irrigation 1,900 1,000

--- 600

273929 harvesting 1,100

500

--- 1,300 transplanting 230

scouting 210

300

--- 2,100 hand weeding 70

Bushberry (Subgroup 13B) (berry, low) irrigation 1,900

500 0.11 ST: 17,000
IT: 2,200 367060 hand harvesting, scouting 1,100

transplanting 230

scouting 210

hand weeding, canopy management 70

Corn (field) (field/row crops, tall) irrigation 1,900

--- --- --- --- scouting 1,100

scouting 210

hand weeding 70

Corn (sweet/pop) (field/row crops, tall) detasseling, hand harvesting 17,600

--- --- --- 251257 irrigation 1,900

scouting 1,100

### Page 26 of 30 Table 9

. Occupation al Post

- Application Exposure Scenarios for Halosulfuron

- Methyl.

Use Site
(TC Group) Activity Current
Dermal

TC Assessed
TC 1 DFR 2 Dermal
MOE 3 DP
Barcode 4

scouting 210

hand weeding 70

Cotton (field/row crops, low/medium) scouting 210

--- --- --- 251257 hand weeding 70

Nut, Tree (Crop Group 14) (tree, “nut”) scouting 580

--- --- --- 251257 transplanting 230

mechanical harvesting 190

poling, orchard

maintenance 100

Okra (vegetable, fruiting) irrigation 1,900

--- --- --- --- hand harvesting,

tying/training 1,100

transplanting 230

scouting 210

hand weeding 70

Pea and Bean, Dried Shelled, Except Soybean (Subgroup 6C) (field/row crops, low/medium) irrigation 1,900

100 0.11 ST: 83,000
IT: 11,000 367060 scouting 1,100

Pea and Bean,
Succulent Shelled (Subgroup 6B) (field/row crops, low/medium) irrigation 1,900

--- --- --- --- hand harvesting 1,100

scouting 210

hand weeding 70

Rhubarb (vegetable, leafy) irrigation 1,900

--- --- --- --- hand harvesting 1,100

transplanting 230

scouting 210

hand weeding 70

Rice scouting 1,100

--- --- --- 251257

### Page 27 of 30 Table 9

. Occupation al Post

- Application Exposure Scenarios for Halosulfuron

- Methyl.

Use Site
(TC Group) Activity Current
Dermal

TC Assessed
TC 1 DFR 2 Dermal
MOE 3 DP
Barcode 4

(field/row crops, low/medium) hand weeding 70

Sorghum, Grain (milo) (field/row crops, low/medium) scouting 210 1,000 0.11 ST: 4,500
IT: 910 223266 hand weeding 70

Soybean (field/row crops, low/medium) scouting 1,100 1,500 0.14 ST: 4,200
IT: 560 359456 hand weeding 70 100 0.14 ST: 63,000 IT: 8,400

Sugarcane (sugarcane) hand harvesting 17,600

--- --- --- 251257 scouting 1,100

hand weeding 70

Vegetable, Cucurbit (Crop Group 9) (vegetable, cucurbit) irrigation 1,900

--- --- --- --- hand harvesting, turning, training, assisted mechanical harvesting 550

transplanting 230

scouting, hand weeding, hand pruning, thinning
fruit 90

Vegetable, Fruiting (Crop Group 8) (vegetable, fruiting) irrigation 1,900

1,000 0.11 ST: 8,300
IT: 1,100

278588 hand harvesting,

tying/training 1,100

hand harvesting,

tying/training 550

transplanting 230

500 0.11 ST: 17,000
IT: 2,200 scouting 210

hand pruning, scouting, hand weeding, thinning
fruit 90

hand weeding, hand pruning 70

Vegetable, Tuberous
and Corm (Subgroup 1C) (vegetable, “root”) irrigation 1,900 1,500 0.11 ST: 5,500
IT: 740 367060 hand harvesting 1,100

scouting 210 300 0.11 ST: 28,000

### Page 28 of 30 Table 9

. Occupation al Post

- Application Exposure Scenarios for Halosulfuron

- Methyl.

Use Site
(TC Group) Activity Current
Dermal

TC Assessed
TC 1 DFR 2 Dermal
MOE 3 DP
Barcode 4

hand weeding 70 IT: 3,700

Non

- Agricultural Uses

Non

- Crop Areas, Turfgrass (turf/sod) maintenance, slab harvesting, transplanting/planting, roll harvesting 6,700

--- --- --- 278588

maintenance 3,700

--- --- ---

Ornamentals (unassigned) irrigation 1,900

--- --- ---

278588 hand harvesting, hand

pruning, scouting, container moving, hand weeding, transplanting, grafting, propagating, pinching, tying/training 230

--- --- ---

1

--- = not assessed.

2 DFR = dislodgeable foliar residue.

3 MOE = margin of exposure.

4 DP# D 251257 did not assess any post

- application exposure estimates because “b ased on the timing of application (pre

emergent or postemergent during early stages of plant growth), there is expected to be minimal dermal c ontact with residue on foliage.”

### Page 29 of 30 Attachment 6

Outstanding Deficiencies to be Addressed by the Registrants

Data Requirements

Toxicology

870.7800 Immunotoxicity

● A n immunotoxicity study is required under 40 CFR §158.500

.

Residue Chemistry

860.1650 Submittal of Analytical Reference Standards

● Analytical reference standards are available for halosulfuron

- methyl and the 3

- CSA (3

- chlorosulfonamide acid) m etabolite but not for the rearrangement ester ( RRE ) of
halosulfuron

- methyl (e

- mail from C. Stafford, ACB/BEAD, 11/16/11). An analytical
referenc e standard for the rearrangement ester ( RRE ) of halosulfuron

- methyl must be submitted to the EPA National Pesticide Standards Repository

.

Occupational and Residential Exposure

None.

### Page 30 of 30 Label Amendments

I n connection with D366410:

860.1200 Directions for Use

● For Crop Subgroup 6B (pea and bean, succulent shelled), the label for Sandea ® Herbicide (EPA Reg

. No

. 81880

- 18) should be amended to prohibit applications to legumes grown for livestock feeds because no residue data are available for cowpea
fora ge and hay. The statement “Do not apply to cowpea used for livestock feed” should
be added instead of the statement “Do not feed to livestock”.

● For Crop Subgroup 13

- 07B (bushberry), the label for Sandea ® Herbicide (EPA Reg

. No

. 81880

- 18) should be amen ded 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.