### UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON

, 

## D.C

. 20460

OFFICE OF CHEMICAL SA FET Y

AND P O LLUTI O N PRE V ENTION



### MEMORANDUM

Date: l 5-SEP-2015



### SU B JECT: S ulfom eturon Methyl. Draft Human H ea lth Ri s k Assessment in Support of

Re g i st ration Re v i ew.

P

C Code : 1 2200 I



### MRID No.: NA

Petition No.: NA DP Barcode: 0 42702 8

R egistration No.: N A

R eg ulatory Action: Reg i s rration R ev i ew
Case No.: 3 1 36 Risk Assessment Type: NA

TXR No.: NA CAS No.: 74222-97-2



### F ROM:

T HR U:

TO: Kell y M. Lowe

, E n v ironment a l Scientist

## -::?«-e**~** Sara h 

### J

. L evy, Chemist

. Monique M. Perr o n
, Sc.D

. , T ox i cologis t

## ~**;17~** Ri sk Assessment Branch l (RA BI )

Health Effects Di v i s ion ( HED: 7509P)

Thurston G. Mort o n, Acting Branch

## hief**~** Geo r ge F. Kram er, Ph.D.

, Senior Chem i st**~:iiiilll~+-,r::~-'o::-::? --**  

### RAB l / HED ( 7509P)

Ca i tlin Newcamp

P estic i d e R e-eva lu a tion Di v i sio n ( PRD ; 750 8P )

As part of R eg i s trati o n Re v i ew, PRO of the O ffic e of Pe st i c ide Pro g ram s ( OPP ) ha s requested

that H E D evaluate t h e ha za rd and e xpo s ure data

, and conduct occupational and r es i d e n t i al

expos ur e assessments

, as n ee ded

, to est im ate th e ri s k to human h ea l th that will resu l t from t he

curre ntl y r egiste red u ses o f pe s ti c ide s. Thi s memor a ndum serves as HED ' s draft human h ea l th

ri s k assessment of the dietary

, occupationa l and r esidential e xpo s ure
, and ag g regat e ri s k fr o m th e registered u ses of s ul fo m etu ron m et h y l.

Since the la st human hea l th risk assessment (W

. Brin o n e l 

### al.; 

### 2 0-DE C-20 07 ; D346064 ) and

sco pin g docum e nt (W. B ritton el al.; 

### 08-NOY-2012 ; 040 2498)

, t h e fo ll ow in g updat es h av e b een inco rp o rat e d fo r s ul fo meturon m e th y l.

• T he s ubchr o nic inh a lation

, imrnunot ox i city

, and n e uroto x i c ity (ac ute a nd s ub c hroni c)

st

ud y r e quir e ment s ha ve bee n wa i ved.

• The acute di et ar y endpoint has b ee n r e moved

, and an in cidental o ral end point for sp ra y dr ift assess m e nt ha s b ee n a dded.

• T h e occ upati o nal ri s k a ssess m e nt ha s been updat e d to in corporate new sc i ence po l icies.

Pa ge I of32Su l fometuron methyl Draft Human Health Risk Assessment 04 27028



### • A high-end drinking water exposure va lu e was u s ed to assess screening- l eve l dietary exposure/risk es timat es.

Pa ge 2 of32Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 3 of 32 

### Table of Contents

1.0 Executive Summary

................................ ................................ ................................ ................................ 4

2.0 HED Recommendations

................................ ................................ ................................ .......................... 5

2.1 Tolerance Considerations

................................ ................................ ................................ ........... 5

2.2 Label Considerations

................................ ................................ ................................ ................. 5 3.0 Ingredient Profile

................................ ................................ ................................ ................................ .... 6 3.1 Chemical Identity and Physical/Chemical Properties

................................ ................................ 6

3.2 Use Pattern

................................ ................................ ................................ ................................ . 6 3.3 Anticipated Exposure Pathways

................................ ................................ ................................ . 6

3.4 Consideration of Environmental Justice

................................ ................................ .................... 6 4.0 Hazard Identification/Toxicology

................................ ................................ ................................ ........... 7 4.1 Summary of Toxicological Effects

................................ ................................ ............................ 7 4.2 Safety Factor for Infants and Children (FQPA SF)

................................ ................................ ... 7 4.3 Toxicity Endpoint and Point of Departure Selections

................................ ................................ 7 4.4 Endocrine Disruption

................................ ................................ ................................ ................. 9 5.0 Dietary Exposure and Risk Assessment

................................ ................................ ................................ 10

5.1 Water Residue Profile

................................ ................................ ................................ .............. 10 5.2 Dietary Exposure and Risk Estimates

................................ ................................ ...................... 11 6.0 Residential (Non

- Occupational) Exposure and Risk Assessment

................................ ......................... 12 6.1 Spray Drift

................................ ................................ ................................ ............................... 12

6.1.1 Combin ed Risk Estimates from Lawn Deposition Adjacent to Applications

.......... 12 6.2 Residential Bystander Post

- Application Inhalation Exposure

................................ ................. 13 7.0 Aggregate Exposure and Risk Assessment

................................ ................................ ........................... 13 8.0 Cumulative Exposure/Risk Characterization

................................ ................................ ........................ 13 9.0 Occupational Exposure/Risk Characterization

................................ ................................ ..................... 13 9.1 Occupational Handler Exposure/Risk Estimates

................................ ................................ ..... 13 9.2 Occupational Post

- application Exposure/Risk Estimates

................................ ........................ 17 Appendix A: Chemical Identity Tables.

................................ ................................ ................................ .... 20 Appendix B: Sulfometuron Methyl Acute, Subchronic, and Chronic Toxicity Profile.

............................ 21 Appendix C: Registered Sulfometuron Methyl Use Patterns

................................ ................................ .... 24 Appendix D: Dietary Exposure/Risk Modeling Input and Output

................................ ............................. 27 Appendix E. Review of Human Research

................................ ................................ ................................ . 28 Appendix F. Occupational Non

- cancer Algorithms

................................ ................................ .................... 29 Appendix G. Spray Drift Detailed Description

................................ ................................ ........................... 31Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 4 of 32 

### 1.0 Executive Summary

Sulfometuron methyl [ methyl 2

- [[[[(4,6

- dimethyl

- 2

- pyrimidinyl)amino]carbonyl]amino] sulfonyl]benzoate ], is a sulfonylurea (SU) herbicide that provides broad spectrum pre

- and post

emergence control of annual and perennial grasses and broad

- leaf weeds in forestry /Christmas

trees and non

- agricultural situations, including vegetative management of rights

- of

- way and

railroads. Similar to other SU herbicides, sulfometuron methyl’s mode of action involves inhibiting th e activity of the enzyme acetolactate synthase (ALS), which inhibits the production of amino acids required for cell growth in plants.

The toxicity database for sulfometuron methyl is adequate to support current registration requirements; currently, no additional toxicological studies are required. Subchronic inhalation, immunotoxicity, and neurotoxicity (acute and subchronic) studies are not available for sulfometuron methyl, as required in accordance with the current 40 CFR Part 158 Toxicology

Data R equirements. However, the Hazard and Science Policy Council (HASPOC) determined

that these studies are not required at this time for sulfometuron methyl (K. Rury; 02

- AUG

- 2012; TXR#0056431 and K. Rury; 06

- AUG

- 2013; TXR# 0056723 ). The latest risk assessment was conducted as part of the Reregistration Eligibility Decision (RED) document (W. Britton; 20

- DEC

- 2007; D346064). No new toxicity and/or met abolism data have been received

. There have been no changes to the prior dose

- response assessment except for th e removal of the acute dietary endpoint and addition of an incidental oral endpoint for spray drift assessment.

For dietary exposure, HED has conducted a screening

- level chronic dietary risk assessment for

sulfometuron methyl using a SU

- class

- wide s creening

- level estimate of residues in drinking

water. Since sulfometuron methyl is a non

- food use chemical, residues in food a re not anticipated

, and the dietary assessment includes only drinking water. D ietary risk estimates range from 2.7 to 9.7 % of the chronic reference dose (c RfD ) and are well below HED’s level of concern (LOC). HED did not conduct an acute or cancer dietary exposure/risk assessment due to the lack of an appropriate endpoint for acute dietary assessment

, and sulfometuron methy l is not likely to be a carcinogen, respectively

.

There are no registered residential uses or uses resulting in direct residential exposure associated

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

S ulfometuron methyl can be applied via groundboom equipment and, therefore, there is the potential for indirect exposure to sulfometuron methyl related to spray drift. As a result, dermal risk estimates for adults and combined dermal plus incidental oral risk estimates for children 1 to <2 years old were calculated. Both children (1 to <2 years old) combined risk estimates, and adult dermal risk estimates result in no risks of concern at the field edge for groundboom applications (screenin g level assumptions for spray type/nozzle configuration). All MOEs are > the LOC o f 100.

In the case of sulfometuron methyl , aggregate exposure and risk estimates are equivalent to the

diet ary exposure and risk estimates, and do not exceed HED’s LOC

.

The occupational handler exposure and risk assessment indicates that f or all scenarios, combined

dermal + i nhalation risk estimates were not of concern (i.e., MOEs > 100) with either baseline protection (long

- sleeved shirt, long pants, shoes plus socks, no gloves or respirator) or with theSulfometuron methyl Draft Human Health Risk Assessment D427028

Page 5 of 32 

### use of gloves, as recommended on certain labels. PRD should ensure the appropriate personal protective equipment (PPE) is listed on registered labels.

Occupational exposures to workers re

- entering sulfometuron methyl

- treated non

- agricultural areas are not anticipated because contact with previously treated areas is unlikely . However, there is a potential for post

- application exposure from the registered forestry /Christmas tree use ; therefore, a quantitative post

- appl ication assessment was conducted for that use

. Short

- and

intermediate

- term dermal post

- application risk estimates are not a concern for the forestry /Christmas tree use on the day of application (i.e., all MOEs ≥ 100).

Sulfometuron methyl is classified as Toxicity Category III via the dermal route and for eye irritation potential, and Toxicity Category IV for dermal irritation potential. It is not a skin

sensitizer. Un der 40 CFR 156.208 (c) (2) , ai’s classified as Toxicity Category III or IV for acute dermal, eye irritation and primary skin irritation are assigned a 12

- hour Restricted Entry Interval ( REI ) . Therefore, the [156 subpart K] Worker Protection Statement REI of 12 hours is adequate to protect agricultural workers from post

- application exposur es to sulfometuron methyl. The occupational post

- application assessment indicated no risks of concern on the day of application as well; therefore, HED recommend s a 12

- hour REI for the sulfometuron methyl labels

.

It is noted that several of the registe red sulfometuron methyl labels require either a 4

- hour or a

48

- hour REI. For some of the labels, multiple active ingredients are included in the end

- use product

, and these additional active ingredients may require a longer REI. REIs may be further

reduce d if certain criteria are met in accordance with the Pesticide Registration (PR) Notice 95

- 3 [Reduction of WPS Interim REIs for Certain Low Risk Pesticides] 1



### . Upon review of the criteria

for the active ingredient only , it appears that sulfometuron methyl i s consistent with the criteria

in PRN 95

- 3 that allow for a 4

- hour REI

. Note : The PR Notice also includes similar criteria for

the end

- use product. These criteria have not been evaluated by HED.

2.0 HED Recommendations

HED has not identified any risk concerns associated with the registered uses of sulfometuron methyl . There are no data gaps that would require submission of additional toxicity, residue chemistry, or exposure data. S ulfometuron methyl is a non

- food use c hemical; therefore, there

are no tolerances. No label ch anges are required at this time

.

2.1 Tolerance Considerations

Sulfometuron methyl is a non

- food use chemical; therefore, there are no tolerances.

2.2 Label Considerations

There are no label recommendations for registered products containing sulfometuron methyl

. A summary of the occupational risk estimates has been provided, and shows that there are no risk

estimates of concern for registered uses of sulfometuron methyl ass uming either baseline protection (long

- sleeved shirt, long pants, shoes plus socks, no gloves or respirator) or with the

use of gloves, as recommended on certain labels. The occupational post

- application assessment indicated no risks of concern on the day of application as well; therefore, HED recommends a

12

- hour REI for the sulfometuron methyl labels. Upon review of the 4

- hr REI criteria for the

1 Available: http://www.epa.gov/PR_Notices/pr95

- 3.htmlSulfometuron methyl Draft Human Health Risk Assessment D427028

Page 6 of 32 

### active ingredient only , it appears that sulfometuron methyl is consistent with the criteria in PRN

95

- 3 that allow for a 4

- hour REI

. Note : The PR Notice also includes similar criteria for the end

use product. These criteria have not been evaluated by HED.

3.0 Ingredient Profile

3.1 Chemical Identity and Physical/Chemical Proper ties

The chemical structure and nomenclature of sulfometuron methyl and a detailed description of the physicochem ical properties are provided in Appendix A

.

3.2 Use Pattern

Sulfometuron methyl is used to control annual and perennial broadleaf weeds and gra sses in forestry /Christmas trees and non

- agricultural sites (i.e., rights of way, non

- crop industrial sites, and unimproved turf). All sulfometuron

- methyl

- containing products are formulated as water

dispersible granules (WDGs). Applications of sulfometuron methyl can be made aerially by

fixed

- wing airplane and helicopter, and by groundboom or hand

- held equipme nt. Additionally,

sulfometuron methyl can be used to impregnate or coat dry bulk fertilizer for application to

forested a reas. Maximum application rates are 0.281 lb ai/A

, and 0.053 lb ai/gal or 0.00281 lb ai/gal depending on the use site

. PPE recommended on registered labels typically includes long

sleeved shirts, long pants

, and socks , with some labels also recommending the use of chemical

resistant gloves and protective eyewear. REIs range from 4 hours to 48 hours, depending on the product. Several products contain multiple active ingredients ; however, this assessment only pertains to sulfometuron methyl

. A s ummary of th e registered uses are included in Appendix C

.

3.3 Anticipated Exposure Pathways

Based on the regist ered application scenarios, dietary exposure is an anticipated exposure path way as residues of sulfometuron methyl are expected to be found in drinking water. Although t here are no registered r esidential uses of sulfometuron methyl , there is a potential for spray drift that may result in exposure s in residential and non

- occupational settings. In an occupational setting, applicators may be exposed while handling the pesticide prior to application, as well as during application. Occupational exposures to workers re

- entering sulfometuron methyl non

- agricultural treated areas are not anticipated because contact with previously treated areas is unlikely ; ho wever, post

- application exposure is anticipated from the registered forestry /Christmas tree use

. This risk assessment considers all of the aforementioned exposure pathways based on the existing uses of sulfometuron methyl

.

3.4 Consideration of Environmental Justice

Potential areas of environmental justice concerns, to the extent possible, were considered in this human health risk assessment, in accordance with U.S. Executive Order 12898, "Federal Ac tions

to Address Environmental Justice in Min ority Populations and Low

- Income Populations," ( http://epa.gov/compliance/ej/resources/policy/exec_order_12898.pdf ). As a part of every pesticide risk assessment, OPP consi ders 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 t hat subgroup’s food and water consumption, an d activities in and around the home that involve pesticide use in a residential setting. Extensive data on food consumption patterns are compiled by the United StatesSulfometuron methyl Draft Human Health Risk Assessment D427028

Page 7 of 32 

### Department of Agriculture ( USDA ) under the National Health and Nutrition Examination

Sur vey, What We Eat in America, (NHANES/WWEIA; 2003

- 2008) 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 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 pesti cide products and associated risks for adult 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 exper tise to the development of specialized software and models that consider exposure to bystanders and farm workers as well as lifestyle and traditional dietary patterns among specific subgroups.

4.0 Hazard Identification/Toxicology

The toxicology da tabase for sulfometuron methyl, a non

- food use chemical, is considered adequate for risk assessment. Subchronic inhalation, immunotoxicity, and neurotoxicity (acute and subchronic) studies are not available for sulfometuron methyl, as required in accordan ce with the current 40 CFR Part 15 8 Toxicology Data Requirements. However, the HASPOC

determined that these studies are not require d at this time for sulfometuron methyl (K. Rury; 02

- AUG

- 2012; TXR#0056431 and K. Rury; 06

- AUG

- 2013; TXR# 0056723 ). The TOXLI NE (National Library of Medicine) database literature search did not identify any new toxicological information not already considered. The latest risk assessment was conducted as part of the RED document (W. Britton; 20

- DEC

- 2007; D346064). No new toxici ty and/or metabolism data have

b een received. For a summary of the acute, subchronic

, and chronic toxicity profile, see Appendix B

.

4.1 Summary of Toxicological Effects

Sulfometuron methyl has low acute toxicity via oral, dermal, and inhalation routes of exposure (Toxicity Category II I or IV). It shows minimal eye irritation ( Toxicity Category II I ) and is not a dermal irritant or sensitizer. The primary toxic effect in the toxicological database is hemolytic anemia in dogs. There is no evidence that sulfometuron methyl is a developmental toxicant based on prenatal developmental studies. Sulfometuron methyl is a non

- food use chemical and given its limited use pattern and low likelihood for chronic durations of exposure, roden t chronic toxicity or carcinogenicity studies were not required. Sulfometuron methyl was negative in the mutagenicity/genetic toxicity studies.

4.2 Consideration of Toxicity to Children

FQPA considerations do not apply to sulfometuron methyl for the n on

- food use patterns described in this assessment. However, the HED risk assessment team has reviewed the toxicity

database for indications of susceptibility in the young

. The toxicity database of sulfometuron methyl is considered adequate to assess the qualitative or qu antitative susceptibility in the young.

There is no evidence of increased sus ceptibility in rats or rabbits and no evidence of neurotoxicity

.

4.3 Toxicity Endpoint and Point of Departure SelectionsSulfometuron methyl Draft Human Health Risk Assessment D427028

Page 8 of 32 

### There have been no changes to the prio r dose

- response assessment except for the removal of the acute dietary endpoint and addition of an incidental oral endpoint for spray drift assessment. Previously, the chronic oral toxicity study in dogs was used to evaluate acute dietary exposures;

howev er, the effects seen in the study are not considered to be attributable to a single dose. Although abortions were noted in the rabbit developmental range

- finding study, the effect was only seen at or near the limit dose following repeated dosing; therefor e, the effect is not considered to be due to a single dose. As a result, an endpoint was not selected to evaluate acute dietary exposures.

It is recognized that the studies in the sulfometuron methyl database, including those used for endpoint selection, have not been updated to reflect current policy

, and may be considered conservative. The currently selected points of departure (PODs ) are protective of the effects observed in the sulfometuron methyl database and any updates would not impact the overall findings of the risk assessment given the current risk picture for sulfometuron methyl.

Table 4.3.1. Summary of Toxicological Doses and Endpoints for Sulfometuron Methyl for Use in Dietary and

Non

- Occupational Human Health Risk Assessments

. Exposure

Scenario PO D Uncertainty/ FQPA SFs RfD, LOC for Risk

Assessment Study and Toxicological Effects

Acute Dietary (All populations) A dose and endpoint of concern attributable to a single dose was not observed.

Chronic Dietary (All Populations) NOAEL = 27.5

mg/kg/day UF A = 10X

UF H = 10X cRfD = 0.275

mg/kg/day Chronic Oral Toxicity Study (dog) LOAEL = 148.5 mg/kg/day based on decreases in body weight gain in males, hemolytic anemia, and a slight increase in alkaline phosphatase in both sexes

.

Incidental oral (short

- and

intermediate

term) NOAEL = 27.5

mg/kg/day UF A = 10X

UF H = 10X Residential LOC for

MOE <100 Chronic Oral Toxicity Study (dog) LOAEL = 148.5 mg/kg/day based on decreases in body weight gain in males, hemolytic anemia, and a slight increase in alkaline phosphatase in both sexes

.

Dermal exposure (short

and

intermediate

term) NOAE L = 27.5

mg/kg/day

Dermal absorption

factor = 100% UF A = 10X

UF H = 10X Residential LOC for

MOE <100 Chronic Oral Toxicity Study (dog) LOAEL = 148.5 mg/kg/day based on decreases in body weight gain in males, hemolytic anemia, and a slight increase in alkaline phosphatase in both sexes

. Cancer (oral, dermal, inhalation) Given the limited use pattern and low likelihood for chronic durations of exposure for this

compound, carcinogenicity studies were not required.

Point of d eparture (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

- effect 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 = referenc e dose (a = acute, c = chronic). MOE = margin of exposure. LOC= level of concern.Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 9 of 32 Table 4.3. 2. Summary of Toxicological Doses and Endpoints for Sulfometuron Methyl for Use in Occupational Human Health Risk Assessments

.
Exposure/

Scenario POD Uncertainty

Factors LOC for Risk

Assessment Study and Toxicological

Effects

Dermal exposure (short

and

intermediate

term) NOAEL =

27.5 mg/kg/day

Dermal absorption

factor = 100% UF A = 10X

UF H = 10X Occupational LOC for

MOE <100 Chronic Oral Toxicity Study (dog) LOAEL = 148.5 mg/kg/day based on decreases in body weight gain in males, hemolytic anemia, and a slight

increase in alkaline phosphatase in both sexes

.

Inhalation exposure (short

and

intermediate

term) NOAEL =

27.5 mg/kg/day

Inhalation

assu med equivalent to

oral UF A = 10X

UF H = 10X Occupational LOC for

MOE <100 Chronic Oral Toxicity Study (dog) LOAEL = 148.5 mg/kg/day based on decreases in body weight gain in males, hemolytic anemia, and a slight

increase in alkaline phosphatase in both sexes

. Cancer (oral, dermal, inhalation) Given the limited use pattern and low likelihood for chronic durations of exposure for this

compound, carcinogenicity studies were not required.

Point of d eparture (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

- effect 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). MOE = margin o f exposure. LOC = level of concern.



### 4.4 Endocrine Disruption

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 ou tcomes from exposure to chemicals. Collectively, these stud ies include acute, subchronic and chronic toxicity, including assessments of carcinogenicity, neurotoxicity, developmental, reproductive, and general or systemic toxicity. These studies include e ndpoints which may be susceptible to endocrine influence, inc luding effects on endocrine target organ histopathology, organ weights, estrus cyclicity, sexual maturation, fertility, pregnancy rates, reproductive loss, and sex ratios in offspring. For ecolo gical hazard assessments, EPA evaluates

acute tests and chron ic studies that assess growth, developmental and reproductive effects in different taxonomic groups. As part of its most recent registration decision for sulfometuron 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), sulfometuron methyl is subject to the endocrine screening part of the Endocrine Disrupto r Screening Program (EDSP).

EPA has developed the EDSP to determine whether certain substances (including pesticide active and other ingredients) may have an effect in humans or wildlife similar to an effect produced by a “naturally occurring estrogen, o r other such endocrine effects as the Administrator may desig nate.” The EDSP employs a two

- 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 p otential to interact with E, A, or T hormonal systems will proceed to the next stage of the EDSP where EPASulfometuron methyl Draft Human Health Risk Assessment D427028

Page 10 of 32 

### 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 endo crine

- 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. A second list of chemicals identified for EDSP screening was published on June 14, 2013 2 

### and includes some pestic ides scheduled for Registration Review and chemicals found in water

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

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

website. 3



### 5.0 Dietary Exposure and Risk Assessment

Since sulfometuron methyl is a non

- food use chemical, there are no residue chemistry data requirements, and the dietary exposure assessment includes only drinking water.

5.1 Water Residue Profile

Screening groundwater

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

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

- specific estimated drinking water concentrations (EDWCs) following the usual assessm ent procedures, EFED provided coarse

- screen estimates that should exceed upper

- bound, chemical

- specific EDWCs for any SU. This was achieved by using model inputs (rate, soil mobility, persistence) from all the SU herbicides which yielded the highest drinking water residue estimates . The resulting coarse

- screen EDWCs from PRZM

- GW

were higher than the surface water estimates and were used as conservative estimates of potential residues in drinking water and are summarized in Table 5.1. The chronic dietary exposure assessment for sulfometuron methyl used the post

- breakthrough mean value of 492 μg/L (0.492 ppm).

Table 5.1. PRZM

- GW Coarse

- Screen EDWCs for SUs 1

.

Modeled Scenario K d or K OC Initial Applicatio n 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

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

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

- HQ

- OPPT

- 2009

- 0477

- 0074 for the final second list of

chemicals.

3 http://w ww.epa.gov/endo/Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 11 of 32 Table 5.1. PRZM

- GW Coarse

- Screen EDWCs for SUs 1

.

Modeled Scenario K d or K OC Initial Applicatio n Dates (days post

emergence) Max. Daily Conc.

(μg/L) Mean

Breakthrough Time (yrs) Post

breakthrough Mean (μg/L)

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 Maximum values are bolded.



### 5.2 Dietary Exposure and Risk Estimates

In support of Registration Review, an updated chronic dietary exposure and risk assessment was conducted using Dietary Exposure Evaluation Model software with the Food Commodity Intake Database (DEEM

- FCID)

, ver. 3.16

, which incorporates consumption data from the USDA NHANES/WWEIA; 2003

- 2008

. As noted previously, s ince sulfometuron methyl is a non

- food use chemical, the dietary assessment includes only drinking water. The EDWC of 0.492 ppm was incorporated direct ly into the chronic dietary analysis as “water, direct, all sources” and “water, indirect, all sources.” The chronic dietary exposure estimate s are well below HED’s LOC (<100% c RfD ) for the general U.S. population and all population subgroups (see Table

5

. 2 ). The residue file as well as the results of the chronic assessment are provided in Appendix

D

. An acute dietary assessment was not conducted for sulfometuron methyl because an endpoint of concern attributable to a single dose was not identified. Fur thermore, a cancer dietary assessment was not conducted because, given the limited use pattern and low likelihood for chronic durations of exposure for this compound, carcinogenicity studies were not required.

Table 5 .2 . Summary of Dietary (Food + Drinking Water) Exposure and Risk for Sulfometuron Methyl

.

Population Subgroup 1 Acute Dietary (95th Percentile) Chronic Dietary Cancer

Dietary Exposure (mg/kg/day) % a RfD Dietary Exposure (mg/kg/day) % c RfD Dietary Exposure (mg/kg/day) Risk

General U.S. Population

NA NA 0.010302 3.7

NA NA All Infants (<1 year old) 0.026564 9.7

Children 1

- 2 years old 0.014861 5.4

Children 3

- 5 years old 0.012521 4.6

Children 6

- 12 years old 0.009030 3.3

Youth 13

- 19 years old 0.007513 2.7

Adults 20

- 49 years old 0.010278 3.7

Adults 50

- 99 years old 0.010161 3.7

Females 13

- 49 years old 0.010241 3.7

1 The value for the highest exposed population is bolded.Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 12 of 32 

### 6 .0 Residential (Non

- Occupational ) Exposur e and Risk Assessment

There are no registered residential uses or occupational uses resulting in residential exposure

associated with sulfometuron methyl . Therefore, a quantitative residential exposure assessment was not performed.

6.1 Spray Drift

A detailed description about HED’s spray

- drift policy and how to evaluate the drift potential and

associated risks is available in Appendix G

.

6.1.1 Combined 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 screenin g level agricultural application scenarios. The potential risk estimates from these residues can be calculated using drift modeling onto 50

- feet wide lawns coupled with methods employed for residential risk assess ments for turf products. Sulfometuron methyl is

used in forestry

/Christmas trees and various non

- agricultural sites

, and can be applied via groundboom and aerial equipment. The recommended drift scenario screening level options are

listed below:

• Grou ndboom applications are based on the AgDrift ® 

### option for high boom height and using very fine to fine spray type using the 90th 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).

Both children (1 to < 2 years old) combined incidental oral and dermal risk estimates, and adult dermal risk estimates from exposure to sulfometuron methyl related to spray drift result in no risks of concern at the field edge for aerial and groundboom applications ( screening level assumptions for spray type/nozzle configuration; Table 6.1.1.1). All MOEs are ≥ the LOC or 100.

Table 6.1.1. 1. Sulfometuron Methyl Risk Estimates (MOEs) Related to Indirect Exposure to Spray Drift

.

Lifestage Route of

Exposure Applicati on

Type Spray Type/ Nozzle

Configuration Appl. Rate

(lb ai/A) TTR 1

(ug/cm 2 ) MOEs At Edge of

the Field 2
(LOC = 100)

Adults Dermal Aerial Fine to Medium

0.281 0 .031 1,000

Groundboom High Boom Very fine

to Fine 1, 4 00

Children (1 to < 2 years) Dermal +

Incidental Oral Aerial Fine to Medium 500

Groundboom High Boom Very fine

to Fine 690

1 TTR = Application Rate × F × (1

- D) t × 4.54E8 μg/lb × 2.47E

- 8 acre/cm 2 ; where F = 0.1 and D = 0.10 per day

. 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 fol lowing day. 2. MOE = POD (27.5 mg/kg/day) ÷ Dose (mg/kg/day). For dose algorithms and inputs, see Turf SOP of the 2012 Residentia l SOPs ( http://www.epa.gov/pesticides/science/residential

- exposure

- sop.html ).Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 13 of 32 

### 6.2 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 on issues related to volatilization of pesticides from its FIFRA Scientific Adviso ry 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 subseq uent Volatilization Screening Analysis. 4 

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

- specific inhalation toxicological studies) or further analys e s are required for sulfometuron methyl

.

7 .0 Aggregate Exposure and Risk Assessment

The Food Quality Protection Act of 1996 directs EPA to assess aggregate exposure to pesticide chemical residues, including all anticipated dietary exposures and all other exposures for which

there is reliable information. In the case of sulfometuron methyl , aggregate exposure and risk estimates are equivalent to the dietary exposure and risk estimates ( in Section 5 ), and risk estimates are not of concern to HED (i.e., MOEs ≥ 100).

8.0 Cumulative Exposure/Risk Characterization

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

- for

- screening

analy sis.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 available 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) 5 

### and conducting cumulative risk assessments (CRA) 6



### . The Agency has utilized

this framework to evaluate the SUs of which iodosulfuron

- meth yl

- sodium is a member (J. D’Agostino; D428798; 9/9/15). 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 dat a are required and no further cumulative evaluation is necessary.

9.0 Occupational Exposure/Risk Characterization

9.1 Occupational Handler Exposure/Risk Estimates

Based on current labeling, types of equipment and techniques that can potentially be used, occupational handler exposure is expected from the registered uses on forestry /Christmas trees

and various non

- crop sites. Occupational handlers are anticipated to have short

- term (1

- 30 days)

and intermediate

- term (1

- 6 months) dermal and inhalation exposures. Long

- term exposures (more than 6 months) are not anticipated.

4 Available at: http://www.regulations.gov/#!docketDetail;D=EPA

- HQ

- OPP

- 2014

- 0219.

5 Guidance For Identifying Pesticide Chemicals and Other Substances that have a Common Mechanism of Toxicity (USEPA, 1999)

6 Guidance on Cumulative Risk Ass essment of Pesticide Chemicals That Have a Common Mechanism of Toxicity (USEPA, 2002)Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 14 of 32 

### In support of Registration Review, an updated occupational exposure assessment for sulfometuron methyl was conducted for mixers/loaders and applicators for ae rial and groundboom app lications of a WDG formulation, as well as mixer/loader/applicators performing spot treatments with handheld equipment. The assessment was based on the maximum registered application rate s noted in Appendix C , and maximum area treated per day or gallons

h andled.

Handler exposure and risk were calculated at baseline (long pants, a long

- sleeved shirt, no

chemical

- resistant gloves, and no respirator) and with PPE when necessary

. 

### P P E recommended on registered sulfometuron methyl labels typically includes l ong

- sleeved shirts, long pants

, a nd socks, with some labels also recommending the use of chemical

- resistant gloves and protective

eyewear.

For all scenarios, c ombined dermal + i nhalation risk estimates were not of concern (i.e., MOEs ≥ 100) with either baseline protection (long

- sleeved shirt, long pants, shoes plus socks, no gloves

, or respirator) or with the use of gloves, as recommended on some labels (see Table 9.1.1).Page 15 of 32

Table 9.1.1. Summary of Occupational Handler Exposure and Risk Estimates for Sulfometuron Methyl.

Scenario Crop / Target Category Application

Rate a Amount

Handled /

Area

Treated b Dermal Unit

Exposures (ug/lb ai) Mitigation c Inhalation

Unit Exposures (ug/lb ai) Mitigation c Dermal Dose

(mg/kg/day) d Dermal

MOE e Inhalation

Dose (mg/kg

day) f Inhalation

MOE g Combined

MOE h

Mixer/Loader

DF/WDG

Aerial application Non

- agricultural sites 0.281 lb

ai//A 350 A 227

SL/No G 8.96

No

- R 0.279 99

0.011 2,500 95

51.6

SL/G 0.0634 430 370

DF/WDG

Commercial

Treatment of Dry bulk

Fertilizer Forestry

-- Fertilizer, dry

bulk, impregnated 1.99 lb

ai/ton 960 tons 9.8

EC 0.24

EC 0.234 120 0.00573 4,800 120

DF/WDG

On Farm

Treatment of Dry Bulk

Fertilizer 0.199 lb

ai//A 160 A 227

SL/No G 8.96

No

- R 0.0904 300 0.00356 7,700 290

DF/WDG

Aerial

ULV/Wide

- area application Forestry 0.199 lb

ai//A 1200 A 227

SL/No G 8.96

No

- R 0.678 41

0.0268 1000 39

51.6

SL/G 0.154 180 150

DF/WDG

Groundboom application Non

- agricultural sites 0.281 lb

ai//A 80 A 227

SL/No G 8.96

No

- R 0.0638 430 0.00251 11,000 410

Applicator

Aerial application Non

- agricultural sites 0.281 lb

ai//A 350 A

2.08

EC 0.0049

EC 0.00256 11000 0.00000603 4,600,000 11,000

Aerial

ULV/Wide

- area application Forestry 0.199 lb

ai//A 7500 A 0.0388 710 0.0000914 300,000 710

Groundboom application Non

- agricultural sites 0.281 lb

ai//A 80 A 78.6

SL/No G 0.34

No

- R 0.0221 1,200 0.0000955 290,000 1,200

Mechanically

pressurized Handgun application Rights

- of

- way (e.g., utilities, railroad, roadways) 0.00281 lb

ai/gal 1000 gal 1300

SL/No G 3.9

No

- R 0.0456 600 0.000138 200,000 600

Flagger

Aerial application Non

- agricultural sites 0.281 lb

ai//A 350 A 11

SL/No G 0.35

No

- R 0.0135 2,000 0.00043 64,000 1,900Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 16 of 32 Table 9.1.1. Summary of Occupational Handler Exposure and Risk Estimates for Sulfometuron Methyl.

Scenario Crop / Target Category Application

Rate a Amount

Handled /

Area

Treated b Dermal Unit

Exposures (ug/lb ai) Mitigation c Inhalation

Unit Exposures (ug/lb ai) Mitigation c Dermal Dose

(mg/kg/day) d Dermal

MOE e Inhalation

Dose (mg/kg

day) f Inhalation

MOE g Combined

MOE h

Mixer/Loader/Applicator

DF/WDG Backpack Rights

- of

- way (e.g., utilities, railroad, roadways) 0.00281 lb

ai/gal

40 gal 8260 SL/No

G 2.58

No

- R 0.0116 2,400 0.00000363 7,600,000 2,400

Forestry

0.053 lb

ai/gal 0.219 130 0.0000684 400,000 130 Landscaping, turf (lawns, athletic fields, parks, etc.) Aquatic areas (lakes, ponds, etc.)

Industrial/commercial (tires, rail yards, junk yards, etc.) 0.00281 lb

ai/gal 2510 SL/No

G 30

No

- R 0.00353 7,800 0.0000421 650,000 7,700

DF/WDG Manually

pressurized

Handwand Landscaping, turf (lawns,

athletic fields, parks, etc.) Aquatic areas (lakes, ponds, etc.) 0.053 lb ai/gal 40 gal 100,000

SL/No G

30

No

- R 2.65 10

0.000795 35,000 10

430

SL/G 0.0114 2,400 2,200

Industrial/commercial (tires, rail yards, junk yards, etc.) 0.00281 lb

ai/gal 100,000

SL/No G 0.14 200 0.0000421 650,000 200

DF/WDG Mechanically

pressurized Handgun Landscaping, turf (lawns,

athletic fields, parks, etc.) 0.211 lb

ai//A 5 A 1960 SL/No

G 42

No

- R 0.0259 1,100 0.000554 50,000 1,100

Industrial/commercial (tires, rail yards, junk yards, etc.) 0.00281 lb

ai/gal 1000 gal 1300 SL/No

G 3.9

No

- R 0.0456 600 0.000138 200,000 600

Non

- agricultural sites

Aquatic areas (lakes, ponds, etc.) 0.053 lb ai/gal 1300 SL/No

G 0.861 SL/No

G 32 0.00259 No

R 11,000 32

390 SL/G 0.259 110 110

Bolded MOEs are < HED ’ s LOCPage 17 of 32 a. Based on maximum single application rates on registered labels (Appendix C).

b

. Based on the Science Advisory Council for Exposure Policy 9.1: Standard Values for Daily Acres Treated in Agriculture.

c

. Based on the “ Occupational Pesticide Handler Unit Exposure Surrogate Reference Table ” (March, 2013). Mitigation

Le vel: SL/No G = single layer clothing/no gloves; SL/G = single layer of clothing/gloves; No

- R = no respirator; EC = engineering controls (e.g., enclosed cockpit for aerial applicators).

d

. Dermal Dose (mg/kg/day) = [Rate (lb ai/A or lb ai/gal) * UE (mg/lb a i) * Acres Treated or Amount handled (A or gal /day)] * Dermal Absorption (100%) /BW (80 kg). e. Dermal MOE = POD (27.5 mg/kg/day)/ Dermal Dose (mg/kg/day). LOC = 100. f. Inhalation Dose (mg/kg/day) = [Rate (lb ai/A or lb ai/gal) * UE (mg /lb ai) * Acres Treated or Amount handled (A or gal/day)] /BW (80 kg). g. Inhalation MOE = POD (27.5 mg/kg/day)/ Inhalation Dose (mg/kg/day). LOC = 100. h. Combined MOE = POD (27.5 mg/kg/day) / Combined dose (dermal + inhalation).



### 9.2 Occupational Post

- application Exposure/Risk Estimates

Occupational exposures to workers re

- entering sulfom eturon methyl

- treated non

- agricultural use

sites are not anticipated because contact with previously treated areas is unlikely; therefore, a quantitative post

- application assessme nt was not conducted for those sites

. However, for the forestry / Christmas tree use s , a quantitative occupational post

- application assessment was

conducted. Based on the use directions on product labels, exposure is expected to be minimal for

most of the activities listed below since applications are to be made during the dormant stage of growth, and labels indicate that sprays that come in contact with the foliage may cause injury to

the trees. However, risk estimates for these activities have been inclu ded here as a worst case scenario, and should be considered conservative.

The results of the dermal post

- application exposure and risk assessment indicate that dermal MOEs ≥ LOC (MOEs ≥ 100) on day 0 for all scenarios, and, therefore, are not of concern t o HED.

Table 9.2.1. Summary of Occupational Post

- application Dermal Exposure and Risk Estimates.

Crop Crop Height /

Foliage Density Activity Transfer Coefficient (cm 2 /hr) Residue 1 ,2

(ug/cm 2 ) Dermal Dose 3

(mg/kg

- day) MOE 4

DAT (Day After Treatment) = 0 (12 hours)

Forestry High

Full Harvesting, Seedling

Production 6,700 0.022 0.015 1,800

High

Full Irrigation (hand set) 1,900

0.56 0.106 260

High

Full Harvesting, Seed Cone

(Conifers) 1,400 0.078 350

High

Full / Min Scouting 580 0.078 850

Low

Min Transplanting 230 0.032 2,100

High /Low

Full/Min Hand weeding 100 0.013 4,900

Christmas

tree plantations High/Low

Full/Min Hand weeding,

Grading/Tagging 100

0.14 0.001 20,000

Low

Min Transplanting 230 0.003 8,700

High/Low

Full/Min Scouting / Shaping 580 0.008 3,400

High

Full Hand harvesting 1,400 0.019 1,400Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 18 of 32 Table 9.2.1. Summary of Occupational Post

- application Dermal Exposure and Risk Estimates.

Crop Crop Height /

Foliage Density Activity Transfer Coefficient (cm 2 /hr) Residue 1 ,2

(ug/cm 2 ) Dermal Dose 3

(mg/kg

- day) MOE 4

DAT (Day After Treatment) = 0 (12 hours)

High/Low

Full Irrigation (hand set) 1,900 0.026 1,100

1

. TTR for seedling production/harvesting = Application Rate × F × (1

- D) t × 4.54E8 μg/lb × 2.47E

- 8 acre/cm 2 ; where F = 0.1 and D = 0.10 per day

. 2. DFR for all other activities = 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

3. Daily Dermal Dose = [DFR (μg/cm 2 ) × Transfer Coefficient × 0.001 mg/μg × 8 hrs/day × dermal absorption ( 100 %)]  BW ( 80 kg).

4. MOE = POD ( 27.5 mg/kg/day) / Daily Dermal Dose.



### Sulfometuron methyl is classified as Toxicity Category III via the dermal route and for eye irritation potential, and Toxicity Category IV for dermal irritation potential. It is not a skin sensitizer. Under 40 CFR 156.208 (c) (2) (iii), ai’s classified a s Toxicity Category III or IV for acute dermal, eye irritation and primary skin irritation are assigned a 12

- hour Restricted Entry

Intervals ( REI ) . Therefore, the [156 subpart K] Worker Protection Statement REI of 12 hours is adequate to protect workers f rom post

- application exposures to sulfometuron methyl. The occupational post

- application assessment indicated no risks of concern on the day of application as well; therefore, HED recommends a 12

- hour REI for the sulfometuron methyl labels.

It is noted that several labels require either a 4

- hour or a 48

- hour REI. For some of the sulfometuron methyl labels, multiple active ingredients are included in the end

- use product and these additional active ingredients may require a longer REI. REIs may be reduc ed from 12

- hours if certain criteria are met in accordance with the Pesticide Registration (PR) Notice 95

- 3 [Reduction of WPS Interim REIs for Certain Low Risk Pesticides] 7 

### . In PR Notice 95

- 3, there are a set of criteria listed for the active ingredient t hat must be met for chemicals to be eligible for a

reduced REI. These criteria include:

1. The active ingredient is in Toxicity category III or IV based upon data for acute dermal toxicity, acute inhalation toxicity, primary skin irritation, and primary eye irritation. Acute oral toxicity data were used if no acute dermal data were available. If EPA lacked data on primary skin irritation, acute inhalation, or primary eye irritation of the active ingredient, the Agency reviewed data on that end

- point for simi lar active ingredients (analogs), and excluded such active ingredients from consideration for the reduced REI, if the analog is in Toxicity Category I or II for that endpoint.

2. The active ingredient is not a dermal sensitizer (or in the case of biochemical and microbial active ingredients, no known reports of hypersensitivity exist).

3. The active ingredient is not a cholinesterase inhibitor (NMethyl carbamate and Organophosphate) as these chemicals are known to cause large numbers of pesticide poisonings and h ave the potential for serious neurological effects.

4. No known reproductive, developmental, carcinogenic, or neurotoxic effects have been associated with the active ingredient. If active ingredients did not have data available for

these chronic health effect s, EPA considered data on appropriate chemical and biological analogs. Active ingredients that have been classified as carcinogenic in Category B (probable human carcinogen) or Category C with a potency factor, Q* (possible human carcinogen, for which quan tification of potential risk is considered appropriate), or are scheduled for the Health Effects Division's Cancer Peer Review process, were omitted

from consideration.

7 Available: http://www.epa.gov/PR_Notices/pr95

- 3.htmlSulfometuron methyl Draft Human Health Risk Assessment D427028

Page 19 of 32 

### 5. EPA does not possess incident information (illness or injury reports) that are ``defini tely'' or ``probably'' related to post

- application exposures to the active ingredient.

Upon review of the criteria for the active ingredient only , it appears that sulfometuron methyl

consistent with the criteria in PRN 95

- 3 that allow for a 4

- hour REI

. N ote : The PR Notice also includes similar criteria for the end

- use product. These criteria have not been evaluated by

HED. Based solely on the active ingredient criteria, HED would recommend for reduction of the REI for sulfometuron methyl.Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 20 of 32 

### Appendix A : Chemical Identity Tables.

Table A. 1. Chemical Identity of Sulfometuron Methyl.

Chemical Structure

Empirical Formula C 15 H 16 N 4 O 5 S

Common Name Sulfometuron Methyl

IUPAC name methyl 2

- (4,6

- dimethylpyrimidin

- 2

- ylcarbamoylsulfamoyl)benzoate

CAS Name methyl 2

- [[[[(4,6

- dimethyl

- 2

- pyrimidinyl)amino]carbonyl]amino]sulfonyl]benzoate
CAS Registry Number 74222

- 97

- 2

Chemical Class Pyrimidinylsulfonylurea Herbicides

Table A.2. Physiochemical Properties of Sulfometuron Methyl.

Parameter Value Reference

Molecular Weight 364.4

The Pesticide Manual: A World Compendium, 9 th ed., 1991, C.R. Worthington, ed. The British Crop Protection Council, Surrey, UK pg. 774 Melting point 203

- 205°C

Physical state Colorless Solid

Vapor pressure (25°C) 6.0 x 10

- 5 mm Hg

Water solubility (25°C) 70 ppm

Log Kow (25°C) 1.2Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 21 of 32 

### Appendix B : Sulfometuron Methyl Acute, Subchronic, and Chronic Toxicity Profile.

Table B. 1. Sulfometuron 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

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

no

yes

no

no 1 --

-- yes

--

-- 870.3700 Developmental Toxicity (rodent)

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

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

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

yes

no 2 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)

................... no 2

yes

no 2

no 2

no 2 --

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

no 1

no 1

no --

--

--

--

-- 870.7485 General Metabolism

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

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

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

no

no 1 yes

--

--

1 HASPOC concluded the subchronic inhalation, neurotoxicity (acute and subchronic), and immunotoxicity studies are not required at this time (K. Rury; 02

- AUG

- 2012; TXR#0056431 and K. Rury; 06

- AUG

- 2013; TXR# 0056723).

2 Given the limited use pattern and low l ikelihood for chronic durations of exposure for this compound, rodent chronic toxicity or carcinogenicity studies were not required.Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 22 of 32 Table B.2 . Acute Toxicity Profile

– Sulfometuron Methyl

.

Guideline No. Study Type MRID No.(s) Results Toxicity Category

870.1100 Acute oral rat 43089201 LD 50 >5g/kg IV

870.1200 Acute dermal rabbit 43089202 LD 50 >2g/kg III

870.1300 Acute inhalation rat 43089203 LC 50 >5.0 mg/L IV

870.2400 Acute eye irritation rabbit 00071412 Minimal irritant III

870.2500 Acute dermal irritation rabbit 41672808 Not a dermal

irritant 2 IV

870.2600 Skin sensitization rabbit 43089204 Not a dermal

sensitizer N/A

1 All studies were conducted on technical grade Sulfometuron methyl, of at least 98.8%, purity.

2 Minimal skin irritation was noted in t he acute dermal toxicity study (MRID No. 43089202) and an older dermal irritation study of a 75% formulation (MRID No. 00071411).

Table B.3 . Subchronic, Chronic and Other Toxicity Profile

– Sulfometuron Methyl

Guideline

No. Study Type MRID No. (year)/

Classification/Doses Results

870.3200 21

- Day dermal

toxicity (rabbit) 00126714 (1983)

Acceptable/non

- guideline

M/F: 0, 125, 500, 2000 mg/kg/day NOAEL = 2000 mg/kg/day

. LOAEL n ot observed

.

870.3700a Prenatal

developmental (rabbit) Main study

00078798 (1981) Acceptable/non

- guideline

F: 0, 30, 100, 300 mg/kg/day

Range

- finding 00078797 (1981)

F: 100, 300, 750, 1000 mg/kg/day Maternal NOAEL =300 mg/kg/day (HDT)

. Maternal LOAEL = 750 mg/kg/day based on abortion observed in the range

- find ing study.

Developmental NOAEL = 300 mg/kg/day

. Developmental LOAEL not observed

.

870.3700b Prenatal

developmental in (rat) 00078796 (1981)

Unacceptable/guideline

Run I F: 0, 5,000, 20,000, 40,000 and 60,000 ppm

Run II & III F: 0, 50,

1000

, and 5,000 ppm (433 mg/kg/day) Maternal NOAEL = >433 mg/kg/day

. Maternal LOAEL not observed

.

Developmental NOAEL = >433 mg/kg/day

. Developmental LOAEL not observed

.

870.4100b Chronic toxicity

(dog) 00129051 (1983)

Acceptable/guideline

M: 0, 5.2, 27.5, 152.6 mg/kg/day

F: 0, 5.3, 28.3, and 148.5 mg/kg/day NOAEL = 27.5 mg/kg/day

. LOAEL = 148.5 mg/kg/day, based on hemolytic anemia in both sexes, decreased body

- weight gain in males, and increased alkaline phosphatase in males and females. Effects on body weight were observed beginning on the fourth week of exposure (and persisting throughout the study).

Gene

Mutation Salmonella/

Microsome assay 00078792 (1979)

Acceptable/guideline in

strains TA 1535, TA 1537, TA 98 and TA 100 in the presence or absence

of activation. No mutagenic activity for all strains of bacteria

tested.Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 23 of 32 Table B.3 . Subchronic, Chronic and Other Toxicity Profile

– Sulfometuron Methyl

Guideline

No. Study Type MRID No. (year)/

Classification/Doses Results

Gene

mutation Chinese Hamster

Ovary 00078793 (1981)

Acceptable/guideline

CHO cell line was used to

detect mutations for

HGPRT No mutagenic activity with or without

activation.

Chromo

some aberration Chinese Hamster

Ovary in vitro cytogenetic assay 00146846 (1981)

Acceptable/guideline CHO in vitro assay with

and without activation No increase in chromosome damage and

aberrations.

Un

scheduled

DNA synthesis Unscheduled DNA

synthesis in rat hepatocytes in vitro 00146847 (1983)

Acceptable/guideline No induction of UDS was observed.Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 24 of 32 

### Appendix C : Registered Sulfometuron Methyl Use Patterns

The use information provided in the following table is mostly based on the Biological and Economic Analysis Division’s ( BEAD ) Master Label Report (dated 5/29/2012). One additional product has been registered since this report, was reviewed for this assessment, and was not found to include any additional use sites and/or higher application rates than those included

below.

Use Site Applic. Timing, Type, and Equip. F ormulation Max Application

Rate Restricted Entry

Interval (REI)

Agricultural Fallow

/ Idleland /

Conservation

Reserve When needed

Broadcast

Groundboom and Helicopter Water Dispersible

Granular (WDG) 0.281 lb ai/A 4 hr

Agricultural Rights

Of

- Way /

Fencerows / Hedgerows When needed

Broadcast / Spot

Aerial (aircraft and helicopter),

Groundboom and Handheld WDG 0.281 lb ai/A

0.00281 lb ai/gal 4 hr

Agricultural

Uncultivated Areas When needed

Broadcast / Spot

Aerial (aircraft and helicopter),

Groundboom and Handheld WDG 0.281 lb ai/A

0.053 lb ai/gal 4 hr

Agricultural / Farm

Premises When needed

Broadcast

Groundboom WDG 0.250 lb ai/A NA

Airports/Landing

Fields When needed

Broadcast / Spot

Aerial (aircraft and helicopter),

Groundboom and Handheld WDG 0.281 lb ai/A

0.053 lb ai/gal NA

Forestry Multiple depending on tree type (pre

transplant, post

- transplant, pre

- emergence, post

- emergence, preplant, etc)

Broadcast

Impregnated Fertilizer

Aerial (aircraft and helicopter),

Groundboom WDG 0.199 lb ai/A

0.053 lb ai/gal 4

- 48 hr

depending on label

Christmas Tree

Plantations Preemergence, early postemergence,

dormant

Broadcast

Groundboom, Helicopter WDG 0.049 lb ai/A 48 hr

Commercial /

Industrial Lawns Broadcast

Aerial (aircraft and helicopter),

Groundboom WDG 0.281 lb ai/A NA

Drainage systems When needed

Broadcast WDG 0.281 lb ai/A

0.053 lb ai/gal NASulfometuron methyl Draft Human Health Risk Assessment D427028

Page 25 of 32 Use Site Applic. Timing, Type, and Equip. F ormulation Max Application

Rate Restricted Entry

Interval (REI)

Aerial (helicopter), Groundboom and

Handheld

Industrial /

Construction Areas When needed

Broadcast

Aerial (aircraft and helicopter), Groundboom, Handheld WDG 0.281 lb ai/A

0.00281 lb ai/gal NA

Intermittently

Flooded Areas When needed

Broadcast

Aerial (aircraft and helicopter), Groundboom, Handheld WDG 0.281 lb ai/A

0.00281 lb ai/gal NA

Nonagricultural Rights

- Of

- Way /

Fencerows / Hedgerows When needed

Broadcast

Aerial (aircraft and helicopter), Groundboom, Handheld WDG 0.281 lb ai/A

0.00281 lb ai/gal NA

Nonagricultural

Uncultivated

Areas/Soils When needed

Broadcast

Aerial (aircraft and helicopter), Groundboom, Handheld WDG 0.281 lb ai/A

0.00281 lb ai/gal NA

Ornamental Lawns

and Turf When needed

Broadcast / Spot

Aerial (aircraft and helicopter), Groundboom, and Handheld WDG 0.281 lb ai/A

0.053 lb ai/gal NA

Paved Areas (Private Roads/Sidewalks) Preconstruction

Groundboom WDG 0.25 lb ai/A NA

Rangeland Fall / Spring

Broadcast

Aerial (aircraft) and Groundboom WDG 0.07 lb ai/A 4 hr

Refuse/Solid Waste Sites (Outdoor) When needed

Broadcast / Spot

Aerial (helicopter), Groundboom,

Handheld WDG 0.281 lb ai/A

0.00281 lb ai/gal NA

Sewage Disposal

Areas When needed

Broadcast / Spot

Aerial (aircraft and helicopter), Groundboom, Handheld WDG 0. 281 lb ai/A

0.00281 lb ai/gal NA

Swamps / Marshes / Wetlands / Stagnant

Water When needed

Broadcast / Spot

Aerial (aircraft and helicopter), Groundboom, and Handheld WDG 0.281 lb ai/A

0.053 lb ai/gal NA

Utility Poles / Rights

- of

- Way When needed

Broadcast / Spot WDG 0.281 lb ai/A

0.00281 lb ai/gal NASulfometuron methyl Draft Human Health Risk Assessment D427028

Page 26 of 32 Use Site Applic. Timing, Type, and Equip. F ormulation Max Application

Rate Restricted Entry

Interval (REI)

Aerial (aircraft and helicopter), Groundboom, and HandheldSulfometuron methyl Draft Human Health Risk Assessment D427028

Page 27 of 32 

### Appendix D : Dietary Exposure/Risk Modeling Input and Output

Filename: C: \ Users \ slevy \ Desktop \ Sulfometuron

- methyl \ Sulfo.r08

Chemical: Sulfometuron RfD(Chronic): .275 mg/kg bw/day NOEL(Chronic): 0 mg/kg bw/day RfD(Acute): 0 mg/kg bw/day NOEL(Acute): 0 mg/kg bw/day
Date created/last modified: 04

- 08

- 2015/12:54:12 Program ver. 3.16, 03

- 08

- d
Comment: No acute or cancer; no food uses

- water only

-----------------------------------------------------------------------------------
EPA Crop Def Res Adj.Factors Comment Code Grp Commodity Name (ppm) #1 #2

---------- ---- ------------------------------- ---------- ------ ------ ------- 8601000000 86A Wate r, direct, all sources 0.492000 1.000 1.000
8602000000 86B Water, indirect, all sources 0.492000 1.000 1.000

US EPA Ver. 3.16, 03

- 08

- d

DEEM

- FCID Chronic analysis for SULFO METURON NHANES 2003

- 2008 2

- day

Residue file name: C: \ Users \ slevy \ Desktop \ Sulfometuron \ Sulfo.r08 Adjustment factor #2 used. Analysis Date 04

- 08

- 2015/12:55:03 Residue file dated: 04

- 08

- 2015/12:54:12 Reference dose (RfD, Chronic) = .275 mg/kg bw/day

COMMENT 1: No acute or cancer; no food uses

- water only

=============================================================================== Total exposure by population subgroup

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

Total Exposure

----------------------------------- Population mg/kg Percent of Subgroup body wt/day Rfd

-------------------------------------- ------------- ---------------- Total US Population 0. 010302 3.7% Hispanic 0.009836 3.6%

Non

- Hisp

- White 0.010596 3.9%

Non

- Hisp

- Black 0.008501 3.1%

Non

- Hi sp

- Other 0.011874 4.3% Nursing Infants 0.009320 3.4%

Non

- Nursing Infants 0.034265 12.5%

Female 13+ PREG 0.009700 3.5%

Children 1

- 6 0.013195 4.8%

Children 7

- 12 0.008589 3.1%

Male 13

- 19 0.007082 2.6%

Female 13

- 19/NP 0.007936 2.9%

Male 20+ 0.009598 3.5% Female 20+/NP 0.010821 3.9%

Seniors 55+ 0.009961 3.6%

All Infants 0.026564 9.7%

Female 13

- 50 0.010252 3.7%

Children 1

- 2 0.014861 5.4%

Children 3

- 5 0.012521 4.6%

Children 6

- 12 0.009030 3.3%

Youth 13

- 19 0.007513 2.7%

Adults 20

- 49 0.010278 3.7%

Adults 50

- 99 0.010161 3.7%

Female 13

- 49 0.010241 3.7%Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 28 of 32 

### Appendix E . Review of Human Research

This risk assessmen t relies in part on data from studies in which adult human subjects were intentionally exposed to a pesticid e or other chemical. These data are subject to ethics review pursuant to 40 CFR 26, have received that review, and are compliant with applicable et hics 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://www.epa.gov/pesticides/science/handler

- exposure

- data.html and http://www.epa.gov/pesticides/science/post

- app

- exposure

- data.html

.Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 29 of 32 

### Appendix F

. Occupational Non

- cancer Algorithms

Potential daily exposures for occupational handlers are calculated using the following formulas:

E=UE * AR * A * 0.001 mg/ug

where:

E = exposure (mg ai/day),

UE = unit exposure (μg ai/lb ai),

AR = maximum application rate according to registered labels (lb ai/A), and

A = area treated or amount handled (e.g., A/day).

The daily doses are calculated using the following formula:

ADD= E * AF

BW

where:

ADD = average daily dose absorbed in a given scenario (mg ai/kg/day),

E = exposure (mg ai/day),

AF = absorption factor (inhalation), and

BW = body weight (kg).

MOE : Non

- cancer risk estimates for each application handler scenario are calculated using a MOE, which is a ratio of the toxicological endpoint to the daily dose of concern. The daily inhalation dose received by occupational handlers is compared to the appropriate POD (i.e., NOAEL) to assess the risk to occupational handlers. All MOE values are calculated using the following formula:

MOE= POD

ADD

where:

MOE = margin of exposure: value used by HED to represent risk estimates (unitless),

POD = point of departure (mg/kg/day), and

ADD = average daily dose absorbed in a given scenario (mg ai/kg/day).

Potential daily exposures for occupational post

- ap plication workers are calculated using the following formulas:

DFR t 

### =AR * F* (1

- D) t 

### * ( 4.54E8 ug

lb ) * ( 2.47E

- 8 A

cm 2 

### )

where:Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 30 of 32 

### DFR t 

### = dislodgeable foliage residue on day "t" (μg/cm 2 

### ),

AR = a pplication r ate (lb ai/acre),

F = fraction of ai retained on foliage or 25% (unitless),

D = fraction of residue that dissipates daily or 10% (unitless), and

t = number of days after application day (days)

.

E=TC * DFR t 

### * ET * 0.001 mg

ug

where:

E = e xposure (mg ai/day),

TC = t ransfer coefficient (cm 2 

### /hr),

DFR t 

### = d islodgeable f o liar r esidue on day “t” (μg/cm 2 

### ), and

ET = e xposure t ime (hours/day).

The daily doses are calculated using the following formula:

ADD= E * AF

BW

where:

ADD = average daily dose absorbed in a given scenario (mg ai/kg/day),

E = e xposure (mg ai/day),

AF = absorption fa ctor (dermal and/or inhalation), and

BW = body weight (kg).

Margin of Exposure: Non

- cancer risk estimates for each scenario are calculated using a Margin of Exposure (MOE), which is a ratio of the toxicological endpoint to the daily d ose of concern. The daily dermal dose received by occupational post

- application workers is compared to the appropriate POD ( i.e.

, NOAEL) to assess the risk to occupational post

- application workers

. All

MOE values a re calculated using the following formul a:

MOE= POD

ADD

where:

MOE = margin of exposure: value used by HED to represent risk estimates (unitless),

POD = point of departure (mg/kg/day), and

ADD = average daily dose absorbed in a given scenario (mg ai/kg/day).Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 31 of 32 

### Appendix G . Spray Drift Detailed Description

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 the c hemical may directly contact. Sprays can also deposit on surfaces where individuals come into contact with residues on these surfaces, leading to indirect exposures (e.g., children playing on lawns where residues have deposited next to treated fields).

T he approach to be used for quantitatively incorporating spray drift into risk assessment is based on a premise 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 8 

### . [Direct exposures would include inhalation of the spray plume or being sprayed directly.] Rather, the exposures addressed here are thought to occur indirectly through contact with impacted areas, such a s residential lawns, when compliant applications are conducted. Given this premise, exposures for children (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 analogous to how exposures to turf products are

considered 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 ass essment based on exposure to deposited residues has been completed to address drift from the agricultural applications of sulfometuron methyl . In the spray drift

sce nario, the deposited residue value was determined based on the amount of spray drift that may occur at varying distances from the edge of the treated field using the AgDrift ® 

### (v2.1.1) model

and the Residential Exposure Assessment Standard Operating Procedu res Addenda 1: Consideration of Spray Drift Policy

. Once the deposited residue values were determi ned, the remainder of the spray drift assessment was based on the algorithms and input values specified in

the 2012 Standard Operating Procedures for Residen tial 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 9

, 10 

### . AgDrift ® 

### is appropriate for use only when applications are made by aircraft, airblast orchard sprayers, and groundboom sprayers. When AgDrift ® 

### was developed, a series of screening values (i.e., the Tier 1 option) were incorporated into the model and represent eac h equipment type and use under varied conditions. The screening options specifically recommended in this methodology were selected because they are plausible and represent a reasonable upper bound level of drift for common application methods in agricultu re. These screening options are consistent with how spray drift is considered in a number of ecological risk assessments and in the process use d to develop drinking water concentrations used for risk assessment. In all cases, each scenario is to

be evalu ated unless it is not plausible based on the anticipated use pattern (e.g., herbicides are not typically applied to tree canopies) or specific l abel prohibitions (e.g., aerial applications are not allowed). Section 6.1.1 provides the screening level drift related risk estimates.

8 This approach is consistent with the requirements of th e EPA’s Worker Protection Standard.

9 http://www.agdrift.com/

10 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.Sulfometuron methyl Draft Human Health Risk Assessment D427028

Page 32 of 32 

### 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.