### Bensulfuron-Methyl Human H ea lth Risk Assessment 0429515

UNITED STAT E S ENV I RONMENTAL P ROT E CTION A GENCY WASHINGT O N, D.C. 20460



### ME MO RAN D UM

D A T E : 

### November 30, 20 

### l 5 OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION



### SUB J ECT: Be n s ulfur o n

- M e th y l

. Human H ealt h Risk Assessment for Registration Review.

P C Co d e: 1 28820 Decisio n No.: 509906 P etit i on No.: NA D P Barcodc: 0429515 Reg i strat i on Nos.: 70506-147

, 148; 71085-9,16,23 R eg ul atory Ac ti on: Re gistration Review
R isk Assessment Type: Single Chemica l/ Aggrega1e T XR No. : NA Case No.: 7216 -1 CAS No. : 83055-99-6 MR ID No.: NA



### FROM :

T H ROUGH:

TO: Myron S. Ottley

, Senior Bio Kristin Rury

, Biologist 

# ¥-

Don Wilbur. Senior Chemist Risk Assess ment Branch 3 Health Effects Di v ision (7509P) 40 C FR : § 180.445



### C hri stine Olinger. Chief

# ~~ Risk Assess ment Branch 3 · Health Effects Division (75

--



### Moana Appleyard

, Risk Manager R ev iewer Risk Management and Implementation Branch V (RM53) 

### Pesticide Re-Registration Di vis ion (7508P)



### Bensulfuron-methyl is a systemic herbicide belonging to the pyrimidinylsulfonylurea group of herbicides. I t inhibits the action of the plant enzyme acetolactate sy ntha se (ALS) / acetohydroxy acid synthase (AHAS). Thi s document evaluates the existing uses of bensulfuron-methyl as part of Registration Review and r e pr ese nt s the draft ri sk assessment (ORA). 

### The Agency is reviewing a ll the su l fonylurea herbicides jointly under Registration Review.

Page 1 of 31

### B ensu l furo n- Methyl Hum a n Health Ri s k Assess m e nt 042 95 15

Table of Conten t s

1.0 Exec uti ve S umm ary

..... .... .... ......................... ... .... . ....... .. . .................... .. . . ... .. .. . ... .. . . ... .. . .. .. .. 3 2.0 HED R eco mm endat ion s

.... .. .. . ......... .... ..... ... ... . .. ... . ... . ... .. ...... .. ..... ... .. .. . . ............................. 3 2.1 Tolerance Co n s id erat ion s

.... . .................... . ....................... .. ......... . ...... .. .. . ...... .. .......... . ... 3 2.2 D ata D e fi c i e n c i es

. . ... ... . . ... .. .. . ... .. .. . ... ... . . .. . .... .. ... ... . . ... ... . . ... ..... .. ..... ... .. . . . .... . ...... .. . ... .. . .. .. .. 3 2.3 L a bel R eco mm e ndation s

................................................. ............. ........... 4 3. 0 In tro du ct i o n

..... .. ...... ...... .... ...... .. ............ .. .. .. . ... ..... ... ..... ... ..... .. .. . ... .. .. . . ... ..... .. ... . . ...... . ... .. . 4 3.1 Use Profile & A nticip a ted E xpo s ur e Pathways

.......... .. ..... ... .... ....... . ...... .. ..... .. .. . ......... 4 3.2 Co n s id eratio n of E nvironm e nt a l Ju s tice

... ... ... . .. ...... .. ...... . ...... . ... . .. ... ......... .. ..... .. ......... 4 4.0 H aza rd C h arac t e ri za ti o n

.. ... . . ... .... ... ... . ... .. ... . .. ... .. .. . ... . ... . ...... .. .. . ...... .. ...... .... .... ... .... .... ... . .. 5 5.0 Residue C h em i stry

............................................. .. ...... .. ...... . .. . ...... .. ...... . ... .. .. . .. .. ..... .. .. . ....... 9 6.0 Di etary Risk Assess m e nt

.. . ... . ... . ... . ... .. ........... . ... . ... . ....... . ... . .. .. .. .. .. . ... . .. .. .. .. .. . ..... ... .. . . ... .. .. 10 6.1 Water Residue Profile

... . ................................... . ........... . ...... .. ...... .. . . ... .... . ... . .. . ... .. . . ... .. . 10 6.2 Di etary (Foo d + Water) Ex po s ur e Assessme nt

. ....... . ...... . ..................... . ... . .. .. .. .. .. . ... . . 11 7.0 R esident i a l (No n -Occ upati o nal ) Ex po s ur e/R i sk C h a r acterizat ion

. ... .... .. ....... .. ..... .. .. . 12 7.1 S pr ay Drif t

.... ............. . ... . ... . ... . ....... . ....... .. ................... . ........................................... . ..... 12 7

. 2 Residential B ys tander Post-Application Inhal at i on Ex po s ur e

. .. . ... . ... . .. .. .. . .. .. .. ...... . 14 8.0 Agg r ega t e Expos ure /R i s k C har acter i za tion

... ... ..... .. .. .. .. .. . ... . .. .. ...... . .. ... . . ... .. . .. . ... . .. . ...... 15 9.0 C umul a tiv e Ex po s ur e / Ri sk C har acterizatio n

... . ........ . ... . ..... ...... .. ..... ............. . .......... .... 15 10.0 Occupational Expos ur e/R i s k Characterization

.. ... ..... ...... ... .. . . ........ . ...... .... .. ... ... ..... ..... 15 11.0 Public Health a nd Pe s ti c id e E pid em i o l ogy Data

.. ...... ............ ...... .. ..... ........ . ................. 19 12

. 0 R efere nc es

.. .. .. . .......... ... ..... .... ..... . ...... . ... . ... ........ . ................ . ... . ... . .. . ... ...... ..... ....... . ....... . .. . .. 20 A pp end i x A: Tox ici ty Profile of Bensulfuron-Methyl..

.... . ...... .. ...... .. . . ... .. . .. ... ..... .. . .. . .. .. .. ...... . . 21 Appendix B: Di e t ary Ex po s ure/Ri sk Mo d eli ng Input and Output

.......... .. ...... . ..... .. .. . ....... . 25 A pp e ndi x C: Revie\v of Hum an R esea r c h .

............... .. ...... .. . ... ..... . ....... . ...... . ......... .... ....... . . .. . ... 26 Appendix D: O cc upation a l No n -ca nc er Handl er Ex po s ur e Est imat es and A l gor ithm s

... 27 A pp end ix E. No m e ncl at ure a nd Phy s ical/Chemical Properties

... .................................... . .. . .. 29 Appendix F. International Harmonization

....... ... ..... .. ...... .. .. . ....... . ... ..... .. .. ..... .. ...... ...... .. .. ..... . . 30 A pp e ndi x G. DFR Da ta Waiver R a ti o n a l e

.. . ............ . ....... . ... . .............. . ..... .. ............................ 31



### Pag e 2 of3 1

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 3 of 31 1.0 Executive Su mmary

Bens ulfuron

- methyl, [methyl 2

- [[[[[(4,6

- dimethoxy

- 2

- pyrimidinyl)amino]carbonyl]amino]sulfonyl]methyl]benzoate] , is a systemic herbicide belonging to the pyrimidinylsulfonylurea class of chemicals. It is currently registered for use on rice

. The registrant of bensulfuron

- methyl end

- use products is E.I. duPont de Nemours and Company

. Since the last risk assessment ( W. Wassell, D238880, 11/20/1997 ) and scoping document ( N

. Tsau r , D 389431 , 0 7 / 06 /201 1 )

, toxicity data requirements for all toxicity studies have been met or waived, and the bens ulfuron

- methyl hazard profile has been updated accordingly . T he residue profile no longer includes rice, straw because it is no longer an animal f eed item or a regulated commodity

. D ietary exposure to bens ulfuron

- methyl has been reevaluated in order to incorporate updated consumption data and drinking water modeling estimates. Non

- dietary exposure has also been reevaluated to incorporate changes to occupational exposure assessment methodologies (unit expos ures) and to incorporate a spray drift assessment. There are no risk estimate s of concern for the existing uses of bens ulfuron

- methyl

.

2 .0 HED Recommendations

2.1 Tolerance Considerations

The existing tolerances for bensulfuron

- methyl are listed in 40 CFR § 180.445 and are supported by the available residue chemistry data : Crayfish at 0.05 parts per million (ppm); and rice, grain at 0.02 ppm

. However, HED recommends that the tolerance on rice, straw be revoked since it is no longer an animal feed item or a regulated commodity. The residue of concern for tolerance enforcement is bensulfuron

- methyl only. There are no Maximum Residue Limits (MRLs) or tolerances for bensulfuron

- methyl in Canada or in the Codex system. Please refer to Appe ndix F for a listing of all tolerances.

HED recommends for modification of the tolerance expression for bensulfuron

- methyl according to the new compliance/measurement policy ( Interim Guidance on Tolerance Expressions , Steve Knizner, May 27, 2009) as follows:

Tolerances are established for residues of bensulfuron

- methyl , 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 be nsulfuron

methyl [methyl 2

- [[[[[(4,6

- dimethoxy

- 2

- pyrimidinyl)amino]carbonyl]amino]sulfonyl]methyl]benzoate].

2. 2 Data Deficiencies

None

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 4 of 31 2.3 Label Recommendations

EPA Reg. No. 70506

- 149 should list required personal protective equipment (PPE) based on the acute toxicity of the end

- use product per 40 CFR 170.240. EPA Reg. No. 70506

- 149 should also list a restricted entry interval (REI) based on the acute toxicity of the active ingredient per 40 CFR 156.208.

3.0 Introduction

3.1 Use Profile & Anticipated Exposure Pathways

Bensulfuron

- methyl is formulated as dry flowable (DF) , granular, and liquid formulations. Currently registered labels include one technical /manufacturing use product label, and five end use product labels. The only registered use of bensulfuron

- methyl is on rice. In general, bensulfuron

- methyl may be applied once or twice per year or growing season. Bensulfuron

methyl may be applied using groundboom and aerial application equipment; application via chemigation is prohibited on the registered labels. Most of the registered bensulfuron

- methyl labels require occupational handlers to wear long

- sleeved shirts, long pants, shoes, socks, and chem ical resistant gloves. Bensulfuron

- methyl labels that are co

- formulations with propanil require the addition of chemical resistant footwear, chemical resistant aprons, chemical resistant eyewear, and chemical resistant headgear when handling. Most of the REIs are 24 hours on the registered labels; however EPA Reg. No. 70506

- 149 does not list required PPE or an REI.

Individuals may be exposed to bens ulfuron

- methyl via their diet (food and drinking water) and agricultural workers may be exposed (dermal ly and via inhalation) to bens ulfuron

- methyl during mixing, loading, and/or applying the herbicide as well as during post

- application activities. There are no registered uses for bens ulfuron

- methyl that will result in direct non

- dietary (i.e., residential) exposures. However, there is the potential for indirect exposure (incidental oral and dermal) to bens ulfuron

- methyl related to spray drift. Exposure to bensulfuron

- methyl is expected to be short

- and intermediate

- term for occupational handlers and post

- application workers. Exposure to bensulfuron

- methyl via non

- occupational spray drift is expected to be short

- term only.

Table 3.1. Summary of Directions for Use of Bensulfuron. Applic. Timing, Type, and Equip. Formulation Max. Single Applic. Rate (lb ai/A) Max. No. Applic. per Season Max. Seasonal

Applic. Rate (lb ai/A)
Rice

Groundboom, Aerial 1 DF 0.063 One at max single application rate 0.063
Liquid 0.047 Two 0.062
Granular 0.064 One 0.064 1. Chemigation is not permitted on the registered labels.



### 3

. 2 Consideration of Environmental Justice

Potential areas of environmental justice concerns, to the extent possible, were considered in the preliminary human health risk assessment for bens ulfuron

- methyl , in accordance with U.S.

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 5 of 31 Executive Order 12898, "Federal Actions to Address Environmental Justice in Minority Populations and Low

- Income Populations" 1 

### . As a part of 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 that 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 National Health and Nutrition Examination Surveys/What We Eat in America (NHANES/WWEIA) 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 and ethnic group. Additionally, OPP is ab le 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 a dult applicators and for toddlers, youths, and adults entering or playing on treated areas post

- application are evaluated. Further considerations are currently in development as OPP has committed resources and expertise to the development of specialized s oftware and models that consider exposure to bystanders and farm workers as well as lifestyle and traditional dietary patterns among specific subgroups.

4 .0 Hazard Characterization

The toxicology database for bensulfuron

- methyl is considered complete a nd adequate for risk
assessment. Although g uideline subchronic dermal, subchronic inhalation, subchronic neurotoxicity, immunotoxicity and oncogenicity (rat) studies are not available for bensulfuron

methyl as required in accordance with the current 40 CF R Part 158 Toxicology Data Requirements

, the Hazard and Science Policy Council (HASPOC) determined that these studies are not required at this time for bensulfuron

- methyl 2 

### . The last risk assessment was conducted in 1997 (D238880, W. Wassell, 11/20/1997). Since that risk assessment, an acceptable acute neurotoxicity (ACN) study has been submitted and reviewed. For a summary of the acute, subchronic and chronic toxicity profiles, see Appendix A.

4 .1 Summary of Toxicological Effects

The primary target organ of bensulfuron

- methyl toxicity is the liver. Effects in the mouse included enlarged livers, nodules and masses in the liver, and increased liver weight accompanied by liver elevated liver enzymes ( alkaline phosphatase (AP)

, alanine transaminase ( ALT ) and aspartate aminotransferase ( AST )) and histological lesions at the highest dose tested (455 mg / kg / day). Similar hepatotoxicity

, as well as irritation of oral mucosa, were observed in the chronic dog study at 237 mg /kg / day and above. Adaptive

, non

- adverse changes in liver histology were observed in the chronic rat study at 305 / 405
mg /kg/day (M/F) . Similar to chronic studies, liver effects were seen in the 90

- day subchronic toxicity studies in the mouse and dog at comparable dose levels. Submitted reproductive and

1 http://www.epa.gov/compliance/r esources/policies/ej/exec_order_12898.pdf

2 TXR 0057190, R. Beaver, 08/27/2015 (subchronic neurotoxicity, oncogenicity

-- rat) TXR 0052986, E. Craig, 05/07/2015 (subchronic inhalation) TXR 0056721, K. Rury, 08/26/2013 (subchronic dermal) TXR 0056723, K. Rury, 8/6/2013 (immunotoxicity)

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 6 of 31 developmental toxicity studies indicated that bensulfuron

- methyl induces developmental effects (skeletal variations and reduced ossification in rats, abortions in rabbits) only at levels above the limit do se, and has no adverse effects on reproductive function. Bensulfuron

- methyl did not produce evidence of neurotoxicity in any of the studies in the database, including the acute and subchronic neurotoxicity studies . Bensulfuron

- methyl is not mutagenic in ba cteria or cultured mammalian cells. Bensulfuron

- methyl is classified as "not likely to be carcinogenic to humans" based on no evidence of increased tumor incidence in rats or mice.

Ben s ulfuron

- methyl has low acute toxicity. It is classified as toxicity ca tegory IV for oral and inhalation exposures and toxicity categor y III for dermal exposure. Bensulfuron

- methyl is classified as toxicity category IV for primary eye and skin irritation and is not a dermal

s ensitizer.

4 .2 Safety Factor for Infants and Children (FQPA Safety Factor)

The 10

- fold FQPA Safety Factor is reduced to 1X. The toxicity database of bensulfuron

- methyl is considered complete and adequate to assess the qualitative or quantitative susceptibility in the young, and exposure estimates a re unlikely to underestimate risk. There is no evidence of increased susceptibility in the pre

- natal developmental studies in r abbits and in rats of reproduction study. There was an increase in susceptibility seen in the rat fetuses consisting of skeletal variations and reduced ossification at the dose where maternal toxicity was absent. However, these effects occurred only above the limit dose (1320 mg/kg/day) , and there was a clear No Observed Adverse Effect Level ( NOAEL ) for these effects. In addition, this NOAEL was substantially greater the POD used for risk assessment. Therefore, there is low concern for this finding. There is no concern for neurotoxicity based on the absence of neurotoxicity in the neurotoxicity battery and other studies in the tox icity database.

4 .3 Toxicity Endpoint and Point of Departure Selections

The last dose

- response assessment has been modified to include incident oral, dermal and inhalation endpoints and points of departure ( PODs ) , due to updated exposure scenarios. It is recognized that the studies in the bensulfuron

- methyl database, including those used for endpoint selection, have not been updated to reflect current data evaluation policy and may be considered conservative. The currently selected PODs are protecti ve of the effects observed in the bensulfuron

- methyl database and any updates would not impact the overall findings of the risk assessment given the current risk picture for bensulfuron

- methyl.

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 7 of 31 Table 4.3. Bensulfuron

- methyl Summary of Toxicological Dos es and Endpoints for Use in Dietary, Non

- Occupational, and Occupational Human Health Risk Assessments.

Exposure Scenario Point of

Departure Uncertainty

Factors RfD/

Level of Concern Study & Toxicological Effects

Acute Dietary (general population including infants and children) No toxicological effects attributable to a single dose were identified in any of the studies

.

Chronic Dietary NOAEL = 19.9

mg/kg/day UF A = 10X

UF H = 10X FQPA SF = 1X Chronic RfD =

0.2 mg/kg/day

cPAD = 0.2 mg/kg/day Chronic toxicity study in dogs

(MRID 40889319) LOAEL = 222.6 mg/kg/day based on discoloration and inflammation of oral mucosa; increased liver weight in the presence of increased AP and ALT, and microscopic lesions (inflammation of the gums).

Incidental Oral Short

- and Intermediate Term NOAEL = 36.3

mg/kg/day UF A = 10X

UF H = 10X FQPA SF = 1X LOC for MOE

= 100 90

- Day toxicity study in dogs

(MRID 00147397) LOAEL = 340 mg/kg/day based on moderately elevated alkaline phosphatase and SGPT (ALT) ; decreased weights for heart and ovary/fallopian tube ; liver enlargement and discoloration with bile stasis and centrilobular hepatocyte swelling ; gall bladder calculus ; and vacuolation of the seminiferous tubules.

Dermal Short

- and Intermediate Term NOAE L b =

36.3 mg/kg/day UF A = 10X

UF H = 10X FQPA SF = 1X LOC for MOE

= 100 90

- Day toxicity study in dogs

(MRID 00147397) LOAEL = 340 mg/kg/day based on moderately elevated alkaline phosphatase and SGPT (ALT) ; decreased weights for heart and ovary/fallopian tube ; liver enlargement and discoloration with bile stasis and centrilobular hepatocyte swelling ; gall bladder calculus ; and vacuolation of the seminiferous tubules.

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 8 of 31 Table 4.3. Bensulfuron

- methyl Summary of Toxicological Dos es and Endpoints for Use in Dietary, Non

- Occupational, and Occupational Human Health Risk Assessments.

Exposure Scenario Point of

Departure Uncertainty

Factors RfD/

Level of Concern Study & Toxicological Effects

Inhalation Short

- and Intermediate Term NOAEL c =

36.3 mg/kg/day UF A = 10X

UF H = 10X FQPA SF = 1X LOC for MOE

= 100 90

- Day toxicity study in dogs

(MRID 00147397) LOAEL = 340 mg/kg/day based on moderately elevated alkaline phosphatase and SGPT (ALT) ; decreased weights for heart and ovary/fallopian tube ; liver enlargement and discoloration with bile stasis and centrilobular hepatocyte swelling ; gall bladder calculus ; and vacuolation of the seminiferous tubules.

Cancer Classification: Not likely to be carcinogenic to humans based on no evidence of increased

tumor incidence in rats or mice under the experimental conditions tested.

a Endpoint Selection Table derived from D238880 (W. Wassell, 11/20/1997) and updated with endpoints and points of departure for incidental oral exposures.

b In the absence of dermal absorption data, the dermal absorption factor (DAF) is assumed to be 100%

c Toxicity via the oral and inhalation routes are assumed to be equivalent in terms of nature and severity. Point of Departu re (POD) = A data point or an estimated point that is derived from observed dose

- response data and used to mark the beginning of extrapolation to determine risk associated with lower environmentally relevant human exposures. NOAEL = no observed adverse e ffect level. LOAEL = lowest observed adverse effect level. UF = uncertainty factor. UF A = extrapolation from animal to human (interspecies). UF H = potential variation in sensitivity among members of the human population (intraspecies). RfD = reference dose. MOE = margin of exposure. LOC = level of concern; FQPA = Food Quality Protection Act.



### 4 .4 Endocrine Disruption As required by FIFRA and 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, neurotoxici ty, developmental, reproductive, and general or systemic toxicity. These studies include endpoints which may be susceptible to endocrine influence, including effects on endocrine target organ histopathology, organ weights, estrus cyclicity, sexual maturati on, 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 for bensulfuron

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

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

EPA has developed the EDSP to determine whether certain substances (including pesticide active and other ingredients) may have an effect i n humans or wildlife similar to an effect produced by a “naturally occurring estrogen, or other such endocrine effects as the Administrator

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 9 of 31 may designate.” The EDSP employs a two

- tiered approach to making the statutorily required determinations. Tier 1 co nsists 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 available data. Tier 2 testing is designed to identify any adverse endocrine

- rela ted 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. A second list of chemicals identified for EDSP screening was published on June 14, 2013 3 

### and includes some pesticides schedul ed for Registration Review and chemicals found in water

. Neither of these lists should be construed as a list of known or likely endocrine disruptors.

For further information on the status of the EDSP, the policies and procedures, the lists of chemicals, future lists, the test guidelines and the Tier 1 screening battery, please visit our website. 4



### 5 .0 Residue Chemistry

The only registered use for bensulfuron

- methyl is in/on rice (grain and straw). Related with that use, there is a tolerance set for residues of bensulfuron

- methyl in/on crayfish (cultured in rice paddies).

The nature of the residue of bensulfuron

- methyl in plants and ruminants has been adequately delineated based on metabolism studies conducted in rice and lactating goats, and the results of the metabolism study in lactating goats can be translated to crayfish. The metabolic pathways in plants and rumina nts were found to be similar. The nature of the residue in poultry has not been adequately defined; however, HED has previously concluded that based on the livestock metabolism data (ruminants and poultry) and the absence of detectable residues in rice gr ain, the use on rice can be classified as 40 CFR 180.6 (a)(3), no reasonable expectation of finite residues in livestock commodities. HED has determined that the residue of concern (ROC) for tolerance enforcement and risk assessment is the parent compound ( bensulfuron

- methyl ) for both plants and livestock commodities.

The residue chemistry database is adequate to support current Registration Review data requirements. Adequate field trial and processing studies are available to support the registered

use on rice. The magnitude of the residue and processing studies are supported by adequate storage stability data for bensulfuron

- methyl . Adequate methods are available for enforcement of the currently established tolerances. Adequate confined rotational cr op data are available to support minimum plant

- back intervals of 120 days.

3 See http://www.regulations.gov/#!documentDetail;D=EPA

- HQ

- OPPT

- 2009

- 0477

- 0074 for the final second list of chemicals.

4 http://www.epa.gov/endo/

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 10 of 31 Adequate high performance liquid chromatography methods are available for tolerance enforcement: Method DuPont

- AMR 2866

- 93 for rice and its processed commodities, and Method DuPont AMR 2981

- 94 for crayfish. The methods have been adequately validated for the determination of residues of bensulfuron

- methyl in rice and crayfish. Multi

- residue methods testing data were previously submitted for bensulfuron

- methyl , which indicated that the methods are not applicable for bensulfuron

- methyl determination.

An analytical reference standard for bensulfuron

- methyl with an expiration date of 10/26/2016 is available at EPA’s National Pesticide Standards Repository (e

- mail dated 10/26/2015 fro m Gregory Verdin, Analytical Chemistry Branch/Biological and Economic Analysis Division).

The structure and the physical/chemical properties are summarized in Appendix E

.

6. 0 Dietary Risk Assessment

An updated dietary exposure assessment has been com pleted for bens ulfuron

- methyl to incorporate updated food consumption data and drinking water modeling estimates. The use pattern, PODs, and residue inputs to the dietary assessment have not changed since the previous
assessment.

6 .1 Water Residue Pro file

Screening ground water

- sourced drinking water exposure estimates were generated with the Pesticide Root Zone Model for Ground Water (PRZM

- GW; v.1.07) for use in the SU dietary risk assessments. Rather than produce chemical

- specific estimated drinking wate r concentrations (EDWCs) following the usual assessment procedures, the Environmental Fate and Effects Division (EFED) provided coarse

- screen estimates that should exceed upper

- bound chemical

specific EDWCs for any SU. This was achieved by using model inp uts that represent the use pattern of highest exposure from any SU, the highest soil mobility of any SU residue of concern, and persistence to any route of degradation over time. The resulting highest coarse

- screen EDWCs from PRZM

- GW can be used as conser vative estimates of exposure and are summarized in Table 6.1 (G. Orri c k, D427429, 08/12/2015).

The chronic dietary assessments for bensulfuron

- methyl used the post

- breakthrough time (i.e., the time it takes the compound to reach the ground water after a pplication) mean value of 492 μg/L (0.492 ppm).

Table 6.1 . PRZM

- GW Coarse

- Screen EDWCs for Sulfonylureas 1

.

Modeled Scenario K d or K OC Initial Application Dates (days post

emergence) Max. Daily Conc.

(μg/L) Mean

Breakthrough Time (yrs) Post

breakthrough Mean (μg/L)

WI corn K d 7 449 11.5 415

K OC 7 504 6.9 425

DMV corn K d 7 489 5.3 369

K OC 7 560 3.3 378

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 11 of 31 Table 6.1 . PRZM

- GW Coarse

- Screen EDWCs for Sulfonylureas 1

.

Modeled Scenario K d or K OC Initial Application Dates (days post

emergence) Max. Daily Conc.

(μg/L) Mean

Breakthrough Time (yrs) Post

breakthrough Mean (μg/L)

FL citrus K d 7 429 3.2 351

K OC 7 467 2.3 349

FL potato K d 7 375 2.6 272

K OC 7 407 2.2 275

GA peanut K d 7 197 5.2 156

K OC 7 206 3.9 158

NC cotton K d 7 640 8.7 492

K d 37 641 8.7 491

K d 67 637 8.7 490

K OC 7 742 5.7 484

K OC 37 751 5.7 483

K OC 67 744 5.7 482

1 The m aximum value is bolded and was used in the chronic dietary assessment.



### 6 .2 Dietary (Food + Water) Exposure Assessment

HED has conducted a screening

- level chronic dietary risk assessment for bensulfuron

- methyl using tolerance

- level residues in foods and a sulfonylurea

- class

- wide screening

- level estimate of residues in drinking water (G. Orri c k, D427429, 08/12/2015). Expos ure and risk estimates were obtained from the Dietary Exposure Evaluation Model using the Food Commodity Intake Database (DEEM

- FCID; version 3.16). The model uses food consumption data from the 2003

- 2008 NHANES/WWEIA (National Health and Nutrition Examina tion Survey, What We Eat in America) database, coupled with recipe files and residues in foods, to derive estimates of dietary exposure and risk. Generally, HED is concerned when dietary exposure estimates exceed 100% of the population adjusted dose (PAD) . In the case of bensulfuron

- methyl , the dietary risk estimates (Table 6.2 ) range from 3.8 to 13.3% of the cPAD and are below HED’s level of concern. Because of the very conservative assumptions used in the analysis (tolerance level residues, 100% crop t reated, and upper

- bound modeled drinking water estimates), actual exposure and risk are expected to be much lower than those shown in Table 6.2 . The listing of inputs to the assessment is included in Appendix B . HED did not conduct an acute dietary
expos ure/risk assessment because an acute dietary POD was not selected for bensulfuron

- methyl

. Bensulfuron

- methyl is considered “not likely to be carcinogenic to humans”; therefore a cancer dietary risk assessment was also not conducted.

Table 6.2 . Summary of dietary exposure and risk estimates for Bensulfuron

- methyl

.

Population Group Chronic Estimates
Exposure, mg/kg bw/day Risk, % cPAD
Total US Population 0.010309 5.2 All Infants (< 1 year old) 0.026584 13.3 Children 1

- 2 years old 0.014875 7.4 Children 3

- 5 years old 0.012532 6.3

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 12 of 31 Table 6.2 . Summary of dietary exposure and risk estimates for Bensulfuron

- methyl

.

Population Group Chronic Estimates
Exposure, mg/kg bw/day Risk, % cPAD

Children 6

- 12 years old 0.009037 4.5 Youth 13

- 19 years old 0.007517 3.8 Adults 20

- 49 years old 0.010287 5.1 Adults 50

- 99 years old 0.010166 5.1 Female 13

- 49 years old 0.010247 5.1



### 7.0 Residential (Non

- Occupational) Exposure/Risk Characterization

There are no registered residential uses or occupational uses resulting in residential exposure to bens ulfuron

- methyl. Therefore, a quantitative residential exposure assessment was not performed.

7 .1 Spray Drift

Off

- target movement of pesticides can occur via many types of pathways and it is governed by a variety of factors. Sprays that are released and do not deposit in the application area end up off

target and can lead to exposures to those it ma y directly contact. They can also deposit on surfaces where contact with residues can eventually lead to indirect exposures ( e.g. , children playing on lawns where residues have deposited next to treated fields). The potential risk estimates from these resi dues can be calculated using drift modeling onto 50 feet wide lawns coupled with methods employed for residential risk assessments for turf products.

The approach to be used for quantitatively incorporating spray drift into risk assessment is based
on a p remise of compliant applications which, by definition, should not result in direct exposures to individuals because of existing label language and other regulatory requirements intended to prevent them. 5 

### Direct exposures would include inhalation of the sp ray plume or being sprayed directly. Rather, the exposures addressed here are thought to occur indirectly through contact with impacted areas, such as residential lawns, when compliant applications are conducted. Given this premise, exposures for childre n (1 to 2 years old) and adults who have contact with turf where residues are assumed to have deposited via spray drift thus resulting in an indirect
exposure , are the focus of this analysis , which is analogous to how exposures to turf products are conside red in risk assessment.

In order to evaluate the drift potential and associated risks, an approach based on drift modeling coupled with techniques used to evaluate residential uses of pesticides was utilized. Essentially, a residential turf assessment based on exposure to deposited residues has been completed to address drift from the agricultural applications of bensulfuron. In the spray drift scenario, the deposited residue value was determined based on the amount of spray drift that may occur at

var ying distances from the edge of the treated field using the AgDrift (v2.1.1) model and the Residential Exposure Assessment Standard Operating Procedures Addenda 1: Consideration of

5 This approach is consistent with the requirements of the EPA’s Worker Protection Standard.

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 13 of 31 Spray Drift Policy . Once the deposited residue values were determined, the remainder of the spray drift assessment was based on the algorithms and input values specified in the recently revised (2012) Standard Operating Procedures For Residential Risk Assessment (SOPs)

. A screening approach was developed based on the use of the AgDrift model in situations where specific label guidance that defines application parameters is not available. 6

, 7 

### AgDrift is appropriate for use only when applications are made by aircraft, airblast orchard sprayers, and groundboom sprayers. When AgDrif t was developed, a series of screening values (i.e., the Tier 1 option) were incorporated into the model and represent each equipment type and use under varied conditions. The screening options specifically recommended in this methodology were selected be cause they are plausible and represent a reasonable upper bound level of drift for common application methods in agriculture. These screening options are consistent with how spray drift is considered in a number of ecological risk assessments and in the p rocess used to develop drinking water concentrations used for risk assessment. In all cases, each scenario is to be evaluated unless it is not plausible based on the anticipated use pattern (e.g., herbicides are not typically applied to tree canopies) or specific label prohibitions (e.g., aerial applications are not allowed). Section 7.1.1 provides the screening level drift related risk estimates.

In many cases, risks are of concern when the screening level estimates for spray drift are used as the basis for the analysis. In order to account for this issue and to provide additional risk management options additional spray drift deposition fractions were also considered. These drift estimates represent plausible options for pesticide labels.

7.1.1 Combin ed Risk Estimates From Lawn Deposition Adjacent to Applications

The spray drift risk estimates are based on an estimated deposited residue concentration as a result of the screening

- level agricultural application scenarios. Bensulfuron

- methyl is used only on rice and can be applied via aerial and ground equipment. The recommended drift scenario screening level options are listed below:

 Groundboom applications are based on the AgDrift option for high boom height with very fine to fine spray type
, and use the 90 th 

### percentile results.

 Aerial applications are based on the use of AgDrift Tier 1 aerial option for a fine to medium spray type and a series of other parameters which will be described in more detail below (e.g., wind vector assumed to be 10 mph in a downwind direction for entire application/drift event). 8



### Dermal and incidental oral risk estimates were combined for children 1 to <2 years old because the toxicity endpoint for each route of exposure was the same for both exposure routes. The

6 http://www.agdrift.com/

7 Note that for many cases the scenarios outlined in the screening approach represent actual use practice so risk assessors should be aware and characterize these appropriately.
8 AgDrift allows for consideration of even finer spray patterns characterized as very fine to fine. However, this spray pattern was not selected as the common screening basis since it is used less commonly for most agriculture. If assessors identify this use patt ern it should be used as the screening criteria and deposition values associated with it are provided in Table 1 below. Justification for including this spray quality should be included in any assessment based on specific label directions for its use.

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 14 of 31 applicable Levels of Concern (LOC) for each exposure route is 100; therefore MOEs < 100 are of concern. None of the adult or children (1 to <2 years old) risk estimates from indirect exposure to bensulfuron

- related spray drift result in risks of con cern at field edge.

Table 7.1.1. Adult Dermal Risk Estimates (MOEs) Related to Spray Drift Exposure to Bensulfuron

- methyl from the Registered Agricultural Uses. Application Type Spray Type/Nozzle

Configuration Appl. Rate

(lb ai/A) TTR

( μg/cm 2 ) 1 At Edge (LOC = 100)

Rice 1 Aerial Fine to Medium 0.063 0.0070 6,000

Groundboom High Boom Very fine to Fine 8,200

1 HED’s default assumption that 10% of the application is available for transfer on day 0 following the application and the residues dissipate at a rate of 10% each following day.

Table 7.1.2. Combined Dermal and Incidental Oral (Hand to Mouth) Exposure f or Children 1 < 2 Years Old Risk Estimates (MOEs) Related to Spray Drift Exposure to Bensulfuron



### - methyl from the Registered Agricultural Uses. Application Type Spray Type/Nozzle

Configuration Appl. Rate

(lb ai/A) TTR

( μg/cm 2 ) 1 At Edge (LOC = 100)

Rice Aerial Fine to Medium 0.063 0.0070 3,000

Groundboom High Boom Very fine to Fine 4,100

1 HED’s default assumption that 10% of the application is available for transfer on day 0 following the application and the residues dissipate at a rate of 10% each following day.



### 7

. 2 Residential Bystander Post

- Application Inhalation Exposure

Volatilization of pesticides may be a source of post

- application inhalation exposure to individuals nearby pesticide applications. The agency sought expert advice and input o n issues related to volatilization of pesticides from its Federal Insecticide, Fungicide, and Rodenticide Act Scientific Advisory Panel (SAP) in December 2009, and received the SAP’s final report on March 2, 2010 (http://www.epa.gov/scipoly/SAP/meetings/20 09/120109meeting.html). The agency has evaluated the SAP report and has developed a Volatilization Screening Tool and a subsequent Volatilization Screening Analysis. 9 

### During Registration Review, the agency will utilize this analysis to determine if data (i.e., flux studies, route

- specific inhalation toxicological studies) or further analysis is required for bensulfuron

- methyl.

9 A vailable at: http://www.regulations.gov/#!docketDetail;D=EPA

- HQ

- OPP

- 2014

- 0219.

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 15 of 31 8.0 Aggregate Exposure/Risk Characterization

The Food Quality Protection Act of 1996 directs EPA to assess aggregate exposure to pes ticide chemical residues . Exposures to be aggregated includ e anticipated dietary , residential handler, and residential post

- application exposures. Since there are no residential uses for bens ulfuron

methyl that would result in contributions to the aggregate assessment, short

- and intermediate

term aggregate risk assessments are not required. A ggregate exposure and risk estimates are equivalent to the dietary exposure and risk estimates discus sed in Section 6 of this document, and are not of concern.

9.0 Cumulative Exposure/Risk Characterization

In 2015, EPA’s Office of Pesticide Programs released a guidance document entitled, Pesticide Cumulative Risk Assessment: Framework for Screening Analys is [ http://www.epa.gov/oppfead1/cb/csb_page/updates/2015/frame work

- for

- screening

analysis.html ]. This document provides guidance on how to screen groups of pesticides for cumulative evaluation using a two

- step approach beginning with the evaluation of ava ilable toxicological information and if necessary, followed by a risk

- based screening approach. This framework supplements the existing guidance documents for establishing common mechanism groups (CMGs) [1] 

### and conducting cumulative risk assessments (CRA) [ 2]



### . The Agency has utilized this framework to evaluate the SUs of which bens ulfuron

- me thyl is a member (J. D’Agostino, D428798

, 0 9/ 0 9/15). Although the SUs share some chemical and toxicological characteristics, the toxicological database does not support a testable hypothesis for a common mechanism of action. No further mechanistic data are required and no further cumulative evaluation is necessary.

10.0 Occupational Exposure/Risk Characterization

There is potential occupational dermal and inhalation exposure from the registered uses of bensulfuron

- methyl . The quantitative exposure/risk assessment developed for occupational handlers is based on the scenarios listed in Appendix D

. Occupational Handler Exposure, Assumptions and Risk Estimate Equation s Application Rate : The maximum single application rates are listed in Table 3.1 . Refer to section 3 .0 for a complete use pattern description.

Body Weight & Absorption Factor : The standard body weight (80 kg) was used in this risk assessment since the endpoints selected were not developmental and/or based on fetal effects. Since no inhalation or dermal absorption data are available, toxicity by the dermal and inhalation routes is considered to be equivalent to the estimated toxicity by the oral route o f exposure. Unit Exposures: It is the policy of HED to use the best available data to assess handler exposure. Sources of generic handler data, used as surrogate data in the absence of chemical

- specific data,

[1] Guidance For Identifying Pesticide Chemicals and Other Substances that have a Common Mechanism of Toxicity (USEPA, 1999) [2] Guidance on Cumulative Risk Assessment of Pesticide Chemicals That Have a Common Mechanism of Toxicity (USEPA, 2002)

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 16 of 31 include PHED (Pesticide Handlers Exposure Dat abase) 1.1, and the AHETF (Agricultural Handler Exposure Task Force) database. Some of these data are proprietary (e.g., AHETF data), and subject to the data protection provisions of FIFRA. The standard values recommended for use in predicting handler ex posure that are used in this assessment, known as “unit exposures”, are outlined in the “Occupational Pesticide Handler Unit Exposure Surrogate Reference Table 10 

### .” HED policy on use of surrogate data, including descriptions of the various sources, can be f ound at the Agency website 11



### .

Area Treated : The area treated inputs were based on the Science Advisory Council for Exposure Policy 9.1: Standard Values for Daily Acres Treated in Agriculture (listed in Appendix D )

.
Risk Estimate Equations : The algorit hms used to estimate non

- cancer exposure and dose for occupational handlers can be found in Appendix D.

Combining Exposures/Risk Estimates: Dermal and inhalation risk estimates were combined in this assessment, since the toxicological effects for these exposure routes were similar. Dermal and inhalation risk estimates were combined using the following formula:

Total MOE = Point of Departure (mg/kg/day) ÷ Combined Dermal + Inhalation dose (mg/kg/day)

Summary of Occupational Handl er Non

- Cancer Exposure and Risk Estimate All occupational handler scenarios for the registered uses resulted in MOEs greater than 100 at baseline level of risk mitigation (i.e., baseline attire with no gloves or respirator) or engineering control for aeria l applicat ions (i.e., enclosed cockpits)

. The Agency matches quantitative occupational exposure assessment with appropriate characterization of exposure potential. While HED presents quantitative risk estimates for human flaggers where appropriate, agric ultural aviation has changed dramatically over the past two decades. According the 2012 National Agricultural Aviation Association (NAAA) survey of their membership, the use of GPS for swath guidance in agricultural aviation has grown steadily from the mid

- 1990s. Over the same time period, the use of human flaggers for aerial pesticide applications has decreased steadily from ~15% in the late 1990’s to only 1% in the most recent (2012) NAAA survey. The Agency will continue to monitor all available informati on sources to best assess and characterize the exposure potential for human flaggers in agricultural aerial applications.

HED has no data to assess exposures to pilots using open cockpits. The only data available is for exposure to pilots in enclosed coc kpits. Therefore, risks to pilots are assessed using the engineering control (enclosed cockpits) and baseline attire (long

- sleeve shirt, long pants, shoes, and socks); per the Agency’s Worker Protection Standard stipulations for engineering controls, pilo ts are not required to wear protective gloves for the duration of the application. With this level of protection, there are no risk estimates of concern for applicators.

10 Available: http://www2.epa.gov/sites/production/files/2015

- 09/document s/handler

- exposure

- table

- 2015.pdf

11 Available: http://www2.epa.gov/pesticide

- science

- and

- assessing

- pesticide

- risks/occupational

- pesticide

- handler

exposure

- data

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 17 of 31 Occupational Post

- Application Exposure

Occupational Inhalation Post

- Application Exposure HED uses the term post

- application to describe exposures that occur when individuals are present in an environment that has been previously treated with a pesticide (also referred to as re

entry exposure). Such exposures may occur when workers en ter previously treated areas to perform job functions, including activities related to crop production, such as scouting for pests or harvesting. Post

- application exposure levels vary over time and depend on such things as the type of activity, the nature of the crop or target that was treated, the type of pesticide application, and the chemical’s degradation properties. In addition, the timing of pesticide applications, relative to harvest activities, can greatly reduce the potential for post

- application exposure. There are multiple potential sources of post

- application inhalation exposure to individuals performing post

- application activities in previously treated fields. These potential sources include volatilization of pesticides and resuspension of dus ts and/or particulates that contain pesticides. The agency sought expert advice and input on issues related to volatilization of pesticides from its Federal Insecticide, Fungicide, and Rodenticide Act Scientific Advisory Panel (SAP) in December 2009, and received the SAP’s final report on March 2, 2010 ( http://www.epa.gov/scipoly/SAP/meetings/2009/120109meeting.html ). The agency has evaluated the SAP report and has developed a Volatilization Screening Tool and a subsequent Volatilization Screening Analysi s ( http://www.regulations.gov/#!docketDetail;D=EPA

- HQ

OPP

- 2014

- 0219 ). During Registration Review, the agency will utilize this analysis to determine if data (i.e., flux studies, route

- specific inhalation toxicological studies) or further analysis is required for bensulfuron

. In addition, the Agency is continuing to eval uate the available post

- application inhalation exposure data generated by the Agricultural Reentry Task Force. Given these two efforts, the Agency will continue to identify the need for and, subsequently, the way to incorporate occupational post

- applicati on inhalation exposure into the agency's risk assessments.

Although a quantitative occupational post

- application inhalation exposure assessment was not performed, an inhalation exposure assessment was performed for occupational/commercial handlers. Handl er exposure resulting from application of pesticides outdoors is likely to result in higher exposure than post

- application exposure. Therefore, it is expected that these handler inhalation exposure estimates would be protective of most occupational post

- a pplication inhalation exposure scenarios.

Occupational Post

- application Dermal Exposure Data and Assumptions A series of assumptions and exposure factors served as the basis for completing the occupational post

- application risk assessments. Each assumpti on and factor is detailed below on an individual basis.

Transfer Coefficients: It is the policy of HED to use the best available data to assess post

application exposure. Sources of generic post

- application data, used as surrogate data in the absence of chemical

- specific data, are derived from ARTF exposure monitoring studies, and, as proprietary data, are subject to the data protection provisions of FIFRA. The standard values

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 18 of 31 recommended for use in predicting post

- application exposure that are used in t his assessment, known as “transfer coefficients”, are presented in the ExpoSAC Policy 3 12 

### ” which, along with additional information about the ARTF data, can be found at the Agency website 13 

### . Table 10.1 provides a summary of the anticipated post

- application activities and associated transfer coefficients for the proposed crops/use sites.

Application Rate: The maximum single application rates are listed in Table 3.1 . Refer to section 3 .0 for a complete use pattern description.

Exposure Time: The average occupational workday is assumed to be 8 hours.

Dislodgeable Foliar Residues: Chemical

- specific dislodgeable foliar residue data have not been submitted for bensulfuron

- methyl

. Therefore, this assessment uses HED’s default assumption that 25 % of the application is available for transfer on day 0 following the application and the residues dissipate at a rate of 10% each following day.

Occupational Post

- application Non

- Cancer Dermal Exposure and Risk Estimates The algorithms used to estimate n on

- cancer exposure and dose for occupational post

- application workers can be found in the footnotes of Table 10.1 . The highest registered application rate of the products registered on rice was used as a conservative estimate of exposure (0.064 lb ai/A). The occupational post

- application MOE for scouting following bensulfuron

- methyl exposure is 1,800 on day 0, and are not of concern. Hand weeding was not assessed for the registered uses of bensulfuron

- methyl because it is a herbicide registered to kill b roadleaf weeds; therefor e , it is unlikely that someone would be entering treated fields to weed by hand following bensulfuron

methyl application.

Since the highest estimated occupational post

- application exposure using default DFR values for bensulfuron

- methyl is minimal in comparison to the level of concern (i.e., the calculated MOE is greater than 2 times higher than the level of concern, MOE = 1,800 compared to the LOC of 100); EPA is waiving the 40 CFR 158 DFR data requirement. In this instance, it is unlikely that chemical

- specific DFR data would be needed to further refine exposure assessments or would add appreciably to our overall understanding of the availability of dislodgeable foliar pesticide resid ues for bensulfuron.

Table 10.1 . Occupational Post

- application Non

- Cancer Exposure and Risk Estimates for Bensulfuron

methyl

. Crop/Site Activities Transfer Coefficient (cm 2 /hr) DFR/TTR 1 Dermal Dose (mg/kg/day) 2 MOE 3

Short

- and Intermediate

- Term

Rice Scouting 1100 0.18 0.020 1,800

1 DFR = Application Rate × F × (1

- D) t × 4.54E8 μg/lb × 2.47E

- 8 acre/cm 2 ; where F = 0.25 and D = 0.10 per day. 2 Daily Dermal Dose = [DFR (μg/cm 2 ) × Transfer Coefficient × 0.001 mg/μg × 8 hrs /day × dermal absorption (100%)]  BW (80 kg). 3 MOE = POD (36.3 mg/kg/day) / Daily Dermal Dose (mg/kg/day).

12 Available: http://www2.epa.gov/sites/production/files/2015

- 08/documents/exposac

- policy

- 3

- march2013.pdf

13 Availabl e: http://www2.epa.gov/pesticide

- science

- and

- assessing

- pesticide

- risks/occupational

- pesticide

- post

application

- exposure

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 19 of 31 Restricted Entry Interval Bensulfuron

- methyl is classified as Toxicity Category III via the dermal route and Toxicity Category IV for skin irritation potential. It is not a skin sensitizer. Short

- and intermediate

- term post

- application risk estimates were not a concern on day 0 (12 hours following application) for all post

- application activities. Under 40 CFR 156.208(c)(2), active ingredients classified as Acute III or IV for acute dermal, eye irritation and primary skin irritation are assigned a 12

- hour REI. Therefore, the 156 subpart K Worker P rotection Statement interim REI of 12 hours is adequate to protect agricultural workers from post

- application exposures to bensulfuron. However

, the labels list an REI of 24 hours, which is considered protective of post

- application
exposure.

11.0 Public H ealth and Pesticide Epidemiology Data

T he OPP Incident Data System (IDS)

, the Centers for Disease Control and Prevention/National Institute for Occupational Safety and Health (CDC/NIOSH) and Sentinel Event Notification System for Occupational Risk

- Pestici des (SENSOR) databases were consulted for pesticide incident data on the active ingredient bens ulfuron

- methyl in 2013 and no incidents of concern were identified (S. Recore, D 390061

, 05/31/2011 ); therefore additional analysis is not required

. Bens ulfuron

- methyl is also not included in the Agricultural Health Study (A HS ) , and therefore this study does not provide any additional information on bens ulfuron

- methyl . The Agency will continue to monitor the incident information and if a concern is triggered, add itional analysis will be included in the risk assessment.

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 20 of 31 12.0 References

Author Barcode or

TXR Date Title

William Wassell D238880 11/20/1997 PP#4F4367 & 5F4490

. Human Health Risk Assessment for Bensulfuron

- methyl in/on Crayfish and Rice Straw

. Nancy Tsaur D 389431 07/06/2011 Bensulfuron

- Methyl. Human Health Scoping Document in Support of Registration Review. Shanna Recore D390061 05/31/2011 (to be completed)

G reg Orri c k D427429 07/06/2011 Drinking Water Exposure Assessment for the Registration Review of 22 Sulfonylurea Herbicides
Jaime D’Agostino D428798 09/09/ 20 15 Sulfonylureas: Screening Analysis of Toxicological Profiles to Consider Whether a Candidate Common Mechanism Group Can Be Established. Kristin Rury TXR

0056721 08/26/2013 Bensulfuron

- methyl: Recommendations on the Requirement of a 21/28

- Day Dermal Toxicity Study. Evisabel Craig TXR 0052986 05/07/ 2015 Sulfonylurea Pesticides: Summary of Hazard and Science Policy Council (HASPOC) Meeting on April 2, 2015: Recommendations on Data Requirement for Subchronic Inhalation Studies Kristin Rury TXR 0056723 0 8/ 0 6/2013 Sulfonylureas: Summary of Hazard and Science Policy Council (HASPOC) Meeting on Juely 18, 2013: Recommendations on Data Requirement for Immunotoxicity Studies Ronnie Beaver TXR 0057190 08/27/2015 Bensulfuron

- methyl: Recommendations on the Requirement of a Subchronic Neurotoxicity Study and a Two

- year carcinogenicity Rat Study.

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 21 of 31 Appendix A : Toxicity Data Requirements and Profile of Bens ulfuron

- Methyl

Table A.1. Bensulfuron

- methyl Data Requirements Test Technical Required Satisfied 870.1100 Acute Oral Toxicity

................................ ...................... 870.1200 Acute Dermal Toxicity

................................ ................. 870.1300 Acute Inhalation Toxicity

................................ ............. 870.2400 Primary Eye Irritation

................................ ................... 870.2500 Primary Dermal Irritation

................................ ............. 870.2600 Dermal Sensitization

................................ ..................... yes yes yes yes yes yes yes

yes yes yes yes yes 870.3100 Oral Subchronic (rodent)

................................ .............. 870.3150 Oral Subchronic (nonrodent)

................................ ........ 870.3200 21/28

- Day Dermal

................................ ........................ 870.3250 90

- Day Dermal

................................ ............................. 870.3465 90

- Day Inhalation

................................ ......................... yes yes

no 1

no

no 1 yes

yes

--

--

-- 870.3700 Developmental Toxicity (rodent)

................................ .. 870.3700 Developmental Toxicity (nonrodent)

............................ 870.3800 Reproduction

................................ ................................ yes yes yes yes

yes yes 870.4100a Chronic Toxicity (rodent)

................................ ............. 870.4100b Chronic Toxicity (nonrodent)

................................ ....... 870.4200a Carcinogenicity (rat)

................................ ..................... 870.4200b Carcinogenicity (mouse)

................................ ............... 870.4300 Chronic Toxicity/Carcinogenicity (rodent)

................... yes yes

no 1
yes yes yes 2

yes

-- yes yes 870.5100 Mutagenicity

— Gene Mutation

- bacterial

.................... 870.5300 Mutagenicity

— Gene Mutation

- mammalian

............... 870.5375 Mutagenicity

— Structural Chromosomal Aberrations

.. 870.5385 Mutagenicity

— Structural Chromosomal Aberrations

.. 870.5395 Mutagenicity

— Other Genotoxic Effects

...................... 870.5550 Mutagenicity

— Other Genotoxic Effects

...................... yes yes yes yes yes yes yes

yes yes yes yes yes 870.6100 Acute Delayed Neurotox. (hen)

................................ .... 870.6100 90

- Day Neurotoxicity (hen)

................................ .......... 870.6200a Acute Neurotox. Screening Battery (rat)

...................... 870.6200b 90

- Day Neurotoxicity Screening Battery (rat)

.............. 870.6300 Developmental Neurotoxicity

................................ ....... no

no yes

no 1

no --

-- yes

--

-- 870.7485 General Metabolism

................................ ..................... 870.7600 Dermal Penetration

................................ ....................... 870.7800 Immunotoxicity

................................ ............................ yes

no

no 1 yes

--

-- 1 HASPOC concluded the subchronic dermal, subchronic inhalation, subchronic neurotoxicity, immunotoxicity and rat oncogenicity studies are not required at this time (references in Section 4.0, Footnote #1 ).

2 The combined chronic/carcinogenicity study fulfills this requirement.

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 22 of 31 Table A.2.1. Acute Toxicity Profile of Bensulfuron

- methyl Technical Guideline Number Study Type MRID Results Toxicity Category 870.1100 Acute oral

- Rats 00148295 LD 50 > 5000 mg/kg IV 870.1200 Acute dermal

- Rabbits 40089312 LD 50 > 2000 mg/kg III

870.1300 Acute inhalation

- Rats 40089313 40311905 LC 50 > 5 mg/L IV

870.2400 Primary eye irritation

- Rabbits 00147385 Slight corneal cloudiness (reversible) IV

870.2500 Primary skin irritation

- Rabbits 073650 No dermal irritation IV 870.2600 Dermal sensitization

- Guinea pigs 4217630 Not a dermal sensitizer

---

Table A.2.2. Repeated Dose Toxicity Profile of Bensulfuron

- methyl Technical Guideline Number Study Type MRID (year) Dose Levels, Classification Results

870.3100 90

- day oral

toxicity Rat 00148301

0, 100, 1500, 7500 ppm. 0, 6.3, 93, 474 mg/kg/day males, 0, 7.5, 111, 567 mg/kg/day females

Acceptable/guideline NOAEL = 93 / 111 mg/kg/day M/F LOAEL = 474 / 567 mg/kg/day M/F based on mildly elevated cholesterol values (M), mildly elevated kidney weights (M) and heart weights (F), and slight paleness of the hepatocellular cytoplasm (M)

870.3100 90

- day oral

toxicity Mouse 00147395

0, 300, 1000, 3000, or 10,000 ppm 0, 38.7, 132, 387, 1320 mg/kg/day males 0, 40.7, 133, 407, 1320 mg/kg/day females

Acceptable Guideline NOAEL = 132 / 133 mg/kg/day M/F LOAEL = 387 and 407 mg/kg/day M/F based on deposition in the cortico

- medullary junction of the adrenals in females, and an increase in liver size due to swelling of centrilobular hepatocytes.

870.3150 90

- day oral

toxicity Dog 00147397

0, 100, 1000, or 10,000 ppm 0, 3.2, 32.1, 340 mg/kg/day males 0, 3.6, 32.1, 360 mg/kg/day females

Acceptable Guideline NOAEL = 32.1 / 36.3 mg/kg/day M/F LOAEL = 340 and 360 mg/kg/day M/F based on moderately elevated alkaline phosphatase and SGPT (ALT) levels in the high

- dose at the 1

- , 2

- , and 3

- month sampling intervals, indicating hepatic damage, organ weight changes including elevated weights for liver and testes, and decreased weights for heart, and ovary/fallopian tube, liver enlargement and discoloration with bile st asis and centrilobular hepatocyte swelling, gall bladder calculus, and vacuolation of the seminiferous tubules

870.3200 21

- day dermal

toxicity A dermal toxicity study was not submitted. The requirement for this study has been

waived ( TXR 0056721, K. Rury, 08/26/2013 ).

870.3465 90

- day

inhalation toxicity An inhalation toxicity study was not submitted. The requirement for this study has

been waived. ( TXR 0052986, E. Craig, 05/07/2015 ).

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 23 of 31 Table A.2.2. Repeated Dose Toxicity Profile of Bensulfuron

- methyl Technical Guideline Number Study Type MRID (year) Dose Levels, Classification Results

870.3700 Prenatal

developmental toxicity Rat 40089318 and 40311902

0, 50, 500 or 2000 mg/kg/day

Acceptable/Guideline Maternal NOAEL = 1320 mg/kg/day LOAEL > 1320 mg/kg/day, not established

Developmental NOAEL = 500 mg/kg/day LOAEL = 1320 mg/kg/day based on statistically significant increases in skeletal variations that included extra ribs, reduced ossification of the sternebrae, and reduced ossification of the hyoid bones

870.3700 Prenatal

developmental toxicity Rabbit 40113801 and 40311906

0, 30, 300 or 1500 mg/kg/day

Acceptable/Guideli n e Maternal NOAEL = 300 mg/kg/day LOAEL = 1500 mg/kg/day based on increased incidence of deaths, complete resorptions, abortions, stained tail and red discharge, and reduced food consumption

Developmental NOAEL = 300 mg/kg/day LOAEL = 1500 mg/kg/day based on increased resorptio ns and abortions

870.3800 Multi

- generation

reproduction study Rat 40089316

0, 50, 750, 7500 ppm 0, 2, 30, 309 mg/kg/day males 0, 2.7, 40, 405 mg/kg/day females

Acceptable/Guideli n e Parental NOAEL = 309/405 mg/kg/day LOAEL > 309/405 mg/kg/day

Reproductive NOAEL = 309/405 mg/kg/day LOAEL > 309/405 mg/kg/day

Offspring NOAEL = 309/405 mg/kg/day LOAEL > 309/405 mg/kg/day

870.4100 Chronic Toxicity

Dog 40089319

0, 50, 750 or 7500 ppm 0, 1.4, 21.4 or 237.3 mg/kg/day males 0, 1.4, 19.9, or 222.6 mg/kg/day females

Acceptable/Guideli n e NOAEL = 21.4 / 19.9 mg/kg/day M/F LOAEL = 237.3 / 222.6 mg/kg/day M/F based on discoloration and inflammation of oral mucosa; increased liver weight in the presence of increased AP and ALT and microscopic lesions.

870.4200 Carcinogenicity

Mouse 40089317

0, 10, 150, 2500, 5000 ppm 0, 0.870, 13.35, 226, 455 mg/kg/day Males 0, 0.928, 13.63, 227, 460 mg/kg/day Females

Acceptable/Guideli n e NOAEL = 226 / 227 mg/kg/day M/F LOAEL = 455 / 460 mg/kg/day M/F based on elevate d alkaline phosphatase, ALT, AST, and total cholesterol, increased liver weights, centrilobular hepatocyte swelling (M) and focal hepatocellular necrosis and increased brown pigment deposition of stellate cells (F). There was no dose

- related effect on be nign or malignant tumor formation.

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 24 of 31 Table A.2.2. Repeated Dose Toxicity Profile of Bensulfuron

- methyl Technical Guideline Number Study Type MRID (year) Dose Levels, Classification Results

870.4300 Combined

Chronic/ Oncogenicity Rat 40089316

0, 50, 750, or 7500 ppm. 0, 2.0, 30, 309 mg/kg/day males 0, 2.7, 40, 405 mg/kg/day females.

Acceptable/Guideline (chronic toxicity) Acceptable/non

- Guideline (carcinogenicity) because an MTD was not achieved. However, based on the weight of evidence, a new study is not required (TXR0057190, R. Beaver, 08/27/2015) NOAEL = 309 / 405 mg/kg/day M/F LOAEL > 309 / 405 mg/kg/day M/F Not established

There was no dose

- related effect on benign or malignant tumor formation.

870.6200a Acute

Neurotoxicity Rat 49623601 (2015)

0, 2000 mg/kg

Acceptable/Guideline NOAEL = 2000 mg/kg LOAEL > 2000 mg/kg, not established

870.6200b Subchronic

Neurotoxicity Rat 49623602 (2015)

0, 7500, 10000, 12500, 15000ppm 0, 632, 858, 1061, 1281 mg/kg/day males 0, 704, 934, 1260, 1376 mg/kg/day females

Acceptable/non

- Guideline (study conducted for 28 days in 5 animals/sex/dose, guidelines call for 90 days in 10 animals/sex/dose.) NOAEL = 1281 / 1376 mg/kg/day M/F LOAEL > 1281 / 1376 mg/kg/day M/F, not established.

Waiver request granted for the requirement for a guideline study (TXR 0057190, R. Beaver, 08/27/2015)

870.7485 Metabolism and

Pharmaco

kinetics Rat 00147394

Acceptable/Guideline Absorption of radiolabelled test article from the gut was nearly total. The major elimination routes were the urine (low

- dose), and the feces (high

- dose). No measurable quantities of test article or metabolites were found in respired air. Minute quantities of radioactivity ( < 2.1% were distributed to the body tissues. Approximately half of the doses were eliminated within 24 hours (low

dose), or 48 hours (high

- dose), and nearly 99% was eliminated within 96 hours. The parent compound and 6 metabolites were found in feces, and 8 metabolites were found in urine. 870.7800 Immunotoxicity The requirement for this study has been waived (TXR 0056723, K. Rury, 8/6/2013 ).

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 25 of 31 Appendix B : Dietary Exposure/Risk Modeling Input

US EPA Ver. 3.16, 03

- 08

- d
DEEM

- FCID Chronic analysis for BENSULFURON Residue file: C: \ Users \ dwilbur \ Documents \ DEEM Files \ Bensulfuron \ bensulfuron_chronic.r08 Adjust. #2 NOT used Analysis Date 10

- 26

- 2015 Residue file dated: 10

- 26

- 2015/12:21:07 Reference dose (RfD) = 0.2 mg/kg bw/day
Comment:SU

- 0.492ppm EDWC

- rice and crayfish only

---------------------------------------------------------------------------------- Food Crop Residue Adj.Factors EPA Code Grp Food Name (ppm) #1 #2

---------- ---- --- ---------------------------- ---------- ------ ------ 8000161000 80 Fish

- shellfish, crustacean 0.050000 1.000 1.000 1500323000 15 Rice, white 0.020000 1.000 1.000 1500323001 15 Rice, white

- baby food 0.020000 1.000 1.000 1500324000 15 Rice, brown 0.020000 1.000 1.000 1500324001 15 Rice, brown

- babyfood 0.020000 1.000 1.000 1500325000 15 Rice, flour 0.020000 1.000 1.000 1500325001 15 Rice, flour

- babyfood 0.020000 1.000 1.000 1500326000 15 Rice, bran 0.020000 1.000 1.000 1500326001 15 Rice, bran

- babyfood 0 .020000 1.000 1.000 8601000000 86A Water, direct, all sources 0.492000 1.000 1.000 8602000000 86B Water, indirect, all sources 0.492000 1.000 1.000

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 26 of 31 Appendix C : Review of Human Research

This risk assessment relies in part on data from studies in which adult human subjects were intentionally exposed to a pesticide or other chemical. These data are subject to ethics review pursuant to 40 CFR 26, have received that review, and are compliant with applicable eth ics requirements. For certain studies that review may have included review by the Human Studies Review Board. Descriptions of data sources as well as guidance on their use can be found at: http://www2.epa.gov/pesticide

- science

- and

- assessing

- pesticide

- risks/occupational

- pesticide

handler

- exposure

- data and http://www2.epa.gov/pesticide

- science

- and

- assessing

- pesticide

risks/occupational

- pesticide

- post

- application

- exposure

.

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 27 of 31 Appendix D : Occupational Non

- cancer Handler Exposure Estimates and Algorithms

.

Table D.1. Occupational Handler Short

- and Intermediate

- Term Non

- Cancer Exposure and Risk Estimates for Bensulfuron

- methyl on Rice

.

Exposure Scenario LOC Dermal Unit Exposure (μg/lb ai) 1 Inhalation

Unit Exposure (μg/lb ai) 1 Maximum

Application Rate 2 Area Treated or

Amount Handled Daily 3 Dermal Inhalation Total MOE 8

Baseline Baseline Dose (mg/kg/day) 4 MOE 5 Dose (mg/kg/day) 6 MOE 7

Mixer/Loader Mixing/Loading Dry Flowables for Aerial

Application

100 227 8.96 0.063 lb ai/A 1200 acres 0.215 170 0.00846 4,300 160

Mixing/Loading Dry Flowables for Groundboom Application 200 acres 0.0358 1,000 0.00141 26,000 960

Mixing/Loading Granulars for Aerial

Application
8.4 1.7 0.064 lb ai/A 1200 acres 0.00806 4,500 0.00164 22,000 3,700

Mixing/Loading Granulars for Tractor

- Drawn

Spreader Application 200 acres 0.00135 27,000 0.000273 130,000 22,000

Mixing/Loading Liquids for Aerial

Application 220 0.219 0.063 lb ai/A 1200 acres 0.208 170 0.000208 170,000 170

Mixing/Loading Liquids for Groundboom

Application 200 acres 0.0346 1,000 0.0000345 1,100,000 1,000

Applicator

Applying Sprays via Aerial Equipment

100 5 0.068
0.063 lb ai /A 1200 acres 0.00473 7,700 0.0000643 560,000 7,600

Applying Sprays via Groundboom Equipment 48.6 0.34 200 acres 0.0124 2,900 0.0000535 680,000 2,900

Applying Granulars via Aerial Equipment 1.7 1.3
0.064 lb ai/A 1200 acres 0.00164 22,000 0.00125 29,000 13,000

Applying Granulars via Groundboom

Equipment 9.9 1.2 200 acres 0.00159 23,000 0.000193 190,000 21,000

Flagger

Flagging for Aerial Application

- Liquids 100 11 0.35 0.063 lb ai/A 350 acres 0.00304 12,000 0.0000965 380,000 12,000

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 28 of 31 Table D.1. Occupational Handler Short

- and Intermediate

- Term Non

- Cancer Exposure and Risk Estimates for Bensulfuron

- methyl on Rice

.

Exposure Scenario LOC Dermal Unit Exposure (μg/lb ai) 1 Inhalation

Unit Exposure (μg/lb ai) 1 Maximum

Application Rate 2 Area Treated or

Amount Handled Daily 3 Dermal Inhalation Total MOE 8

Baseline Baseline Dose (mg/kg/day) 4 MOE 5 Dose (mg/kg/day) 6 MOE 7

Flagging for Aerial Application

- Granulars 2.75 0.15 0.064 lb ai/A 0.00077 47,000 0.000042 860,000 45,000

1 Based on the “Occupational Pesticide Handler Unit Exposure Surrogate Reference Table” (02/01/2015); Level of mitigation: Base line. Note that aerial applicators are assessed as enclosed cockpit and baseline represents engineering controls. 2 Based on registered Bensulfuron

- methyl labels. 3 Exposure Science Advisory Council Policy #9.1. 4 Dermal Dose = Dermal Unit Exposure (μg/lb ai) × Conversion Factor (0.001 mg/μg) × Application Rate (lb ai/acre or gal) × Area Treated or Amount Handled (A or gal/day) × DAF (100%) ÷ BW (80 kg). 5 Dermal MOE = Dermal NOAEL (36.3 mg/kg/day) ÷ Dermal Dose (mg/kg/day). 6 Inhalation Dose = Inhalation Unit Exposure (μg/lb ai) × Conversion Factor (0.001 mg/μg) × Application Rate (lb ai/acre or gal ) × Area Treated or Amount Han dled (A or gal/day) ÷ BW (80 kg). 7 Inhalation MOE = Inhalation NOAEL (36.3 mg/kg/day) ÷ Inhalation Dose (mg/kg/day). 8 Total MOE = NOAEL (mg/kg/day) ÷ Dermal Dose + Inhalation Dose.

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 29 of 31 Appendix E. Nomenclature and Physical/Chemical Properties

Chemical Identity Table
Table E .1. Chemical Identity of Bensulfuron

- methyl Common Name bensulfuron

- methyl Company Experimental Name DPX

- F5384 PC Code 128820 IUPAC Name of Acid a α

- [(4,6

- dimethoxypyrimidin

- 2

- ylcarbamoyl)sulfamoyl]

- o

- toluic acid CAS Name of Acid a 2

- [[[[[(4,6

- dimethoxy

- 2

- pyrimidinyl)amino]carbonyl]amino]sulfonyl]methyl]benzoic acid CAS No. 83055

- 99

- 6 Registration Review Case No. 7216

- 1 Chemical Class` Sulfonylurea End

- Use Products Londax® Herbicide, DF, 60% w/w (EPA Reg. No. 70506

- 147) Londax® Herbicide, G, 0.32% w/w (EPA Reg. No. 70506

- 149) Duet® DF, 80% propanil and 0.62% bensulfuron

- methyl w/w (EPA Reg. No. 71085

- 16) Duet® 60 DF, 60.0% propanil and 0.46% bensulfuron

- methyl w/w (EPA Reg. No. 71085

- 23) Duet® Herbicide, E C, 41.2% propanil and 0.32% bensulfuron

- methyl (0.031 lb/lb formulated product) (EPA Reg. No. 71085

- 9) Chemical Structure

a Bensulfuron

- methyl is the methyl ester of the acid.

Table E .2. Physicochemical Properties of Technical Grade Bensulfuron

- methyl

Parameter Value Reference Melting point/range (  C) 181 40089309 Boiling point (  C) Decomposes on melting 40089309 pH 6.4 to 6.9 (slurry in water) 40089309 Density 1.41 g/cc 40089309 Water solubility (25  C) 0.0029 mg/ml at pH 4.8 0.012 mg/ml at pH 5.8 0.120 mg/ml at pH 6.9 40089309

Solvent solubility (g/l at 20  C) hexane 0.00031 ethyl acetate 1.66 methylene chloride 11.72 xylene 0.28 acetonitrile 5.38 methanol 0.99
acetone 1.38 40089309

Vapor pressure at 25  C 2.1 X 10

- 4 mm Hg 40089309 Dissociation constant (pKa) 5.2 40089309 Octanol/Water Partition Coefficient (K ow ) 282 at pH 1.5 4.1 at pH 7.0 40089309

UV/visible absorption spectrum (λ max , nm) Not available

-

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 30 of 31 Appendix F. International Harmonization

Bens ulfuron

- methyl ( 128820; 10/26/15 )

Table F .1. Summary of US and International Tolerances and Maximum Residue Limits Residue Definition : US Canada Mexico 1 Codex 40 CFR §180.445(a): Tolerances are established for residues of the herbicide bensulfuron

- methyl (methyl

2[[[[[(4,6

- dimethoxy

- pyrimidin

- 2

- yl) amino] carbonyl] amino] sulfonyl] methyl] benzoate) None None

Commodity 1 Tolerance (ppm) /Maximum Residue Limit (mg/kg) US Canada Mexico 1 Codex Crayfish 0.05 Rice, grain 0.02 Rice, straw 0.3 Completed by: D. Wilbur; 10/26/2015

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

### Bens ulfuron

- Methyl Human Health Risk Assessment D429515

Page 31 of 31 Appendix G . DFR Data Waiver Rationale

Dislodgeable Foliar Residue (DFR): In accordance with 40 CFR 158, DFR data are required for all occupational (e.g., crop, nursery, greenhouse use sites) or residential (e.g., ornamental and vegetable gardens, pick your own farms, retail tree farms) uses that could result in post

application exposure to foliage. In the absence of chemical

- sp ecific DFR data, EPA uses default values. The 2012 Standard Operating Procedures for Residential Pesticide Exposure Assessment includes an analysis of a number of DFR studies, which resulted in the selection of a revised default values for the fraction of the application rate available for transfer after a foliar application (F AR 

### ). These values are based on an analysis of 19 DFR studies. Since that time, the Agricultural Re

- entry Task Force has submitted information (MRID 49299201) that corrects an appl ication rate error made in the original submission of “ARF039

– Determination of Dermal and Inhalation Exposure to Reentry Workers During Chrysanthemum Pinching in a Greenhouse” (EPA MRID 45344501). As a result, the range of F AR 

### values was revised from 2%

- 89% to 2%

- 47%. In the data, a large range of transferability is observed and this variability can potentially be attributable to many factors such as active ingredient; formulation; field conditions in the studies; weather conditions (e.g., humidity) ; or many other difficult to quantify factors. Although witnessed across multiple chemicals, this range in F AR 

### values is not expected when considering DFR data for a single chemical. At this time, the ARTF submission did not alter the selection of 25% as the reasonable, high

- end default value. Because DFR data are not available for bensulfuron

- methyl , EPA is using the default value of 25%. Although there may be a small degree of uncertainty in the use of the default DFR value for bensulfuron

- methyl (i.e., there is a small chance that the F AR 

### value may exceed the applicable default value ), it is likely that the health

- protective aspects of EPA’s occupational post

- application assessment methodology will more than compensate for this potential uncertai nty. For example, when assessing residential and occupational post

- application exposure to gardens and ornamentals, EPA assumes the following: exposures occur to zero

- day (i.e., day of application) residues every day of the assessed exposure duration ( i.e., EPA assumes that no dissipation or degradation occurs, it doesn’t rain, etc); individuals perform the same post

- application activities performed in the transfer coefficient study day after day (e.g., weeding, harvesting, pruning, etc.); and individua ls engage in these post

- application activities for a high

- end amount of time every day (represented by data reflecting time spent gardening based on survey data).

Given the conservatisms discussed above and the potential compounding nature of these

conser vatisms, EPA is able to rely upon the calculated exposure estimates with confidence that exposure is not being underestimated.

Since the highest estimated occupational post

- application exposure using default DFR values for bensulfuron

- methyl is minimal i n comparison to the level of concern (i.e., the calculated MOE is greater than 2 times higher than the level of concern, MOE = 1,800 compared to the LOC of 100); EPA is waiving the 40CFR DFR data requirement. In this instance, it is unlikely that chemical

- specific DFR data would be needed to further refine exposure assessments or would add appreciably to our overall understanding of the availability of dislodgeable foliar pesticide residues for bensulfuron

- methyl

.