UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D.C. 20460

OFFICE OF PREVENTION, PESTICIDE AND TOXIC SUBSTANCES

MEMORANDUM

Date: January 30, 2010

SUBJECT: Occupational and Residential Risk Assessment to Support the Request for Registration of Aminocyclopyrachlor. its methyl ester and potassium Slit on Turf and Non·crop

areas.

Ingredient: Aminocyclopyrachlor-methyl ester and Potassium salt

Thru: Health Effects DIVIsion / Registration Action Branch 4

# (7509:;P':-)'1//0//\~- Raymond Kent, Branch Chief 

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Susan Hummel, Brach Senior Scientist Health Effects Division Registration Action Branch 4 (7509P)

To: Jessica Ryman Risk Assessor Health Effects Division Registration Action Branch 4 (7509P) DP Barcode: D372493, D358166, D361326, PC Code: 288008,288009,288010 D361329, 0361339, D361341, D361347, D361348, D361353, D361354, D361355, D361358 Registration No, 352-TOG, 352-TOE, 352-INN, 352-

Decision No.: 400976 TOT, 352-IRL, 352-IRE, 352-TOU, 352-T1A, 352- TIL, 352-TIT, 352-IRG, 352-IRU, 352-TOO, 352-ING, 352-INU, 352-INT, 352-IRR, 352-TOI
Petition No.: N/A Regulatory Action: Section 3 Registration

Assessment Type: ORE Re-registration Case No.: <None'

MRlD No.: 475602-09 CAS No.: 858956-08-8, 858954-83!f.'1l58956-35-1 I

TXRNo.: NA 40 CFR: 180.475 

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From: 

### James S 

### Miller, Envirorunental

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Introduction

The registrant, DuPont, Inc. requests the registration of the herbicide arninocyclopyrachlor, its methyl ester, and potassium salt. This memorandum addresses risk from occupational and residential exposure resulting from proposed uses.Table of Contents

1.0 Executive Summary.................................................................................................... .........3

2.0 Use Profile ................................................................................................................ ...........6

3.0 Hazard Profile ....................................................................................................... ...............8

4.0 Occupational Exposure and Risk.......................................................................................11

5.0 Occupational Post-applica tion Exposure and Risk............................................................18

6.0 Non-Occupational/Residentia l Exposure and Risk .......................................................... 19

7.0 Non-Occupational/Resid ential Post Applicati on Exposure and Risk........................21

8.0 Conclusion.... ............................................................................................................ .........25

9.0 References...........................................................................................................................26

Appendices.....................................................................................................................................27

Page 2 of 271.0 Executive Summary

Background and Purpose:

The enclosed occupational and residential expos ure assessment is being conducted as part of EPA’s human health risk assessment for the proposed Section 3 registration for use of aminocyclopyrachlor, its methyl ester and potassium salt, on terrestrial, non-crop areas and lawn/turf. Aminocyclopyrachlor-methyl ester and its potassium salt, (4-Pyrimidinecarboxylic acid, 6-amino-5-chloro-2-cyclopropyl, - methyl) ar e herbicides formulated as a dispersible granular, a granular, and a solubl e liquid for pre-, and or post-em ergence control of broad leaf and woody species weeds; including many terrestri al, riparian invasive, and noxious weeds.

Aminocyclopyrachlor, its methyl ester and potassi um salt belong to a new chemical class of Auxin-type herbicides: the pyrim idine carboxylic acids. Like othe r auxin-type herbicides, the mode of action is disorganized plant growth. No toxic mode of action has been identified in mammalian species. 1

In this registration action aminocyclopyrachlor-m ethyl ester, aminocyclopyrachlor; a potassium salt form, and aminocyclopyrachlor; an acid form are being registered for general weed and brush control on private, public and military lands including sod farms, un-cultivated nonagricultural areas such as airports, highways, ra ilroads, golf courses, lumber yards, wild life habitats, multi family residential complexes, recreation areas, utility rights of way, with residential use specified for lawn/turf.

Use Patterns and Formulations:

Aminocyclopyrachlor-methyl is applied in three different formulations , a water dispersible granular, a granular, and a so luble liquid. For this regist ration action DuPont labels, (DPXKJM44 80XP Herbicide/EPA Reg. No. 352 – TOE), (DuPontTM DPX-MAT28 50SG Herbicide/EPA Reg No. 352-TIT), (DuPontTM DPX-MAT28 240SL Turf Herbicide/EPA Reg No. 352-TOG), and (DuPontTM DPX-MAT28 0.064G La wn Herbicide + Fert ilizer/EPA Reg No. 352-TOT), were used because they represented;

• Crop and “Non-Crop” usage

• Conservative maximum application rates applicable to formulation

• Complete exposure scenario explanations (equipment used for application)

Occupational application scenario s include; aerial (fixed wing or helicopter), ground boom, right of way sprayer, push type spread er, push cyclone spreader, tractor drawn broadcast spreader, and

1 Aminocyclopyrachlor and Aminocyclopyrachlor-Methyl: Human Health Risk Assessm ent for Proposed Outdoor Uses as Herbicides. PC Codes: 288008 (aminocyclopyra chlor), 288009 (aminocyclopyrachlor-methyl), Petition No: XFXXXX, DP Barcode: D. Memorandum dated; 12/13/2009.

Page 3 of 27LOC handgun equipment, which are typically used by a lawn care operator (landscape maintenance personnel). Broadcast applications may be performed by using either a single ground boom, a tractor type broadcast or banded a pplication for pre-plant, pre-emergence, or early post-emergence. Pre-plant ap plications can be made as either a single or split application that is either surface appl ied or incorporated.

Residential application scenar ios include; low pressure handw and, hose-end sprayer, and hand held spreader (belly grinder).

Note ; Applications may be applied at waters edge, however not directly to water.

The proposed product is applied as a granular, a water dispersible granular (i.e. dry flowable), and a soluble liquid.

• Occupational application rates range from a minimum of 1.5 oz. of product/ acre per application (0.07 lbs ae/ Acre ) to a maximum of 9 oz. of product/ acre per season (0.28 lbs ae/ Acre).

• Residential application ra tes range from a minimum of 1.5 oz. of product/ acre per application (0.07 lbs ae/ Acre ) to a maximum of 3.0 oz. of product/ acre (0.108 lbs ae/ Acre).

Note ; Maximum application rates (oz of produc t/acre/season) used in all “Non-Crop Occupational handler” calculati ons are conservative estimate s, whereas typically multiple applications of smaller amounts are conducted, however due to the nature of a “Non-Crop” herbicide, label specific instruction note “one application pe r year” is probable.

There is a potential for short- and intermediate -term residential and occupational exposure to aminocyclopyrachlor-methyl during mixing, loading, application, and post-ap plication activities, however chronic exposure is not expect ed for the proposed use patterns.

Hazard Profile:

Aminocyclopyrachlor,its methyl es ter and potassium salt are classi fied in Toxicity Category IV for acute dermal and skin irritation and Category III for primary eye irritation. Aminocyclopyrachlor exhibits low acute and subchronic toxicity by oral, dermal, or inhalation exposure. The major effects across species were decreased body we ight and decreased body weight gain at the limit dose. There is no appare nt target organ. Aminocyclopyrachlor was not geneotoxic, neurotoxic, immunotoxi c, or toxic to the reproductive system and did not cause developmental toxicity at doses up to the limit dose.

Endpoint Selection:

The dose selected for short-, and intermed iate-term dermal expos ure is a NOAEL of 1000 mg/kg/day, based on a 28 day dermal toxicity study. “No hazard or LOAEL was identified. Furthermore, for purposes of determining inte rmediate-term dermal exposure a 100% dermal

Page 4 of 27absorption factor was used for route-to-route extrapolation from an oral study. The dose selected for short-, and intermediate-ter m inhalation and incidental oral exposure is a NOAEL of 350 mg/kg/day. The LOAEL is 1045 mg /kg/day, based on decreased body weights, body weight gains, food consumption, a nd food efficiency in both sexes.

Cancer Risk:

For this registration action, no food uses were li sted and “no long-term exposure is expected,” therefore a cancer assess ment was not conducted.

Uncertainty Factors

The uncertainty factor applied to aminocyclopyr achlor, its methyl ester and potassium salt was 100X (10X interspecies extrapolat ion x 10X intra-species variabili ty). Food Quality Protection Act (FQPA) considerations do not apply to ami nocyclopyrachlor for the (non-food) use patterns described in this risk assessment. However, the HED risk assessment team has reviewed the toxicity database for indications that young may be particularly sensi tive to the effects of aminocyclopyrachlor, since some products may be used in residential se ttings. The toxicity database to assess the hazard to the general population, as well as the potential sus ceptibility of children, was complete and no evidence of incr eased susceptibility for children was found. Therefore, no other uncertainty factors were required.
Margin of Exposure

The Agency’s level of concern for non-cancer risk s (i.e., target level for MOEs or Margins of Exposure) is defined by the uncerta inty factors (noted a bove) that are applied to the assessment. The total uncertainty factors that have been applied to non-cancer risk assessments are 100 for occupational short-, and intermediate-ter m exposure scenarios. For details, see table 3.1 (Summary of Toxicological Doses and Endpoints for aminocyclopyrachlor, its methyl ester and potassium salt for Use in Human Risk Assessments).

Residential Non-Cancer Risks

• Residential Handler Risk Summary:

Quantification of dermal exposures is not required because no t oxicity was observed in a dermal study conducted at the limit dose 2 . However, residential inhala tion exposures were assessed. All short- and intermediate-term inhalation MOEs for lawn/Turf were greater then 100 (MOE 100), and therefore not of concern for this registration action. >

Occupational Non-Cancer Risks

• Occupational Handler Risk Summary:

2 Memorandum: Aminocyclopyrachlor: Human Health Risk Assessment for Proposed Uses as an Herbicide. Dated; December 1, 2009 PC Code: 288008, 288009, 288010 DP Barcode: D369057

Page 5 of 27As noted above; quantification of dermal exposur es is not required because no toxicity was observed in a dermal study conducted at the limit dose 2 . However, occupational inhalation exposures were assessed. All short- and inte rmediate-term inhalation MOEs for general weed and brush control on private, public and military lands including sod farms, un-cultivated nonagricultural areas such as airports, highways, ra ilroads, golf courses, lumber yards, wild life habitats, multi family residential complexes, recr eation areas, utility rights of way and turf were greater then 100 (MOE > 100), a nd therefore not of concern fo r this registration action.

Occupational Post-Application Risks

• Occupational Post-Application Risk Summary:

Chemical-specific post-applica tion exposure data were submitted (MRID # 47560209) in support of the registration of aminocyclopyr achlor, its methyl ester and pota ssium salt. Turf transferable residues (TTRs), were selected form three test s ites located in California (Porterville), Canada (Branchton) and Georgia (Sycamore). Note; at the Georgia site rainfall occurred and caused substantial lower TTR values, therefore thes e data were not used in this assessment

. However, as noted earlier quantification of dermal expos ures is not required because no toxicity was observed in a dermal study c onducted at the limit dose.

Furthermore, HED believes that based on the oc cupational handler inha lation MOE values of (190,000 - 50,000,000), occupational post-application i nhalation exposures will be negligible and therefore were not assessed in this memorandum. Please see table 4 for specifics.

The draft product label of (352-TIL- DPX-KJM44 80XP) states that because this product is used on sod farms it is within the scope of the Work ers Protection Standard (WPS) for agricultural pesticides (40 CFR Part 170). Label directions call for a restri cted entry interv al (REI) of 4 hours, however due to a category III in acute eye irritation therefore HED ma intains that a REI of 12 hours is appropriate and that all label directions reflect this change.

Residential Post-Application Risks

• Residential Post-Application Risk Summary:

As noted above; chemical-specific post-app lication exposure data was submitted (MRID # 47560209) in support of the registration of aminocyc lopyrachlor, its methyl ester and potassium salt. However, quantification of dermal expos ures is not required because no toxicity was observed in a dermal study c onducted at the limit dose.

Therefore, residential post-application inhalati on, hand to mouth, and soil ingestion exposures were assessed. For all exposur es noted, MOEs for are greater then 100, and therefore were not of concern for this registration action.

2.0 Use Profile A summary of the proposed us e profile is presented in Table 2. Note; for aminocyclopyrachlormethyl, maximum application units are pounds of acid equivalent per acre.

Page 6 of 27Table 2 : Summary of Directions for Use of Aminoc yclopyrachlor-methyl ester and potassium salt Application Equipment Crop(s) Non-Crops EPA Reg. # Max Application Formulation

Non-crop 352-TIA 352-TIT 352-TIL 0.28

Turf/Sod Farm 352-TOE 352-TOU

352-TOE 352-TOU Water Dispersible Granular

Turf/Lawn Golf Course 352-TOG Groundboom (Open Cab)

Turf/Sod Farm. 352-TOG 0.07

Soluble Liquid

Non-crop 352-TIA 352-TIT 352-TIL 0.28 Water Dispersible Granular LCO Handgun Turf/Lawn/Sod Farm/Golf Course 352-TOG 352-TOE 352-TOU 0.07 Soluble Liquid

Aerial (Fixed wing) enclosed cockpit Non-crop 352-TIA 352-TIT 352-TIL 0.28 Water Dispersible Granular

Push Cyclone Spreader
Push Type

Spreader

Tractor Drawn Broadcast Spreader Sod Farm Golf Course 352-IRU 352-IRE 352-IRG 352-TOT 0.108 Granular

Non-crop 352-TIA 352-TIT 352-TIL 0.28 Water Dispersible Granular

Right of way
sprayer Turf/Lawn Sod Farm Golf Course 352-TOG 352-TOE 352-TOU 0.07 Soluble Liquid

Page 7 of 27Table 2: Summary of Directions for Use of Aminocyc lopyrachlor-methyl ester and potassium salt
Application Equipment Crop(s) Non-Crops EPA Reg. # Max Application Formulation

Low Pressure

Handwand

(PHED) Soluble Liquid

Hose-end

Sprayer "mix your own" 0.07

Water dispersible granular

Belly Grinder (PHED) Turf (Lawns) 352-TOG 352-TOE 352-TOU 352-TOT 352-IRG 352-TOI 352-IRU 352-TOO 352-IRL 352-INN 352-ING 352-INU 352-INT 352-IRR 0.108 Granular (dry bulk fertilizer)

3.0 Hazard Profile

The toxicology database for ami nocyclopyrachlor is adequate fo r risk assessment for non-crop and domestic outdoor herbicidal use. Aminocyclopyrachlor, its methyl ester and potassium salt exhibit low acute toxicity by or al, dermal, or inhalation exposure, and neither cause skin sensitization or irritation. All are rapidly absorbed, with rapid metabolic conversion of aminocylopyrachlor-methyl to amin ocylopyrachlor. Elimimation is almost complete within 24 hours. Due to the demonstrated rapid conversion of aminocyclopyrachlor-methyl to aminocyclopyrachlor in mammals, these two chemical s are toxicologically equivalent, and so the toxicology database for aminocyclopyrachlor-methyl can be bridged with aminocyclopyrachlor.

Aminocyclopyrachlor, its methyl ester and potas sium salt are not toxic subchronically via the dermal route of exposure (no toxicity at the limit dose), and subchronic toxici ty via the oral route is low. The major effects across species with subchronic oral administ ration were decreased body weight, body weight gains, food consumption, and f ood efficiency in both sexes at the limit dose. The most sensitive species is the rat, and the most sensitive exposure route is dietary exposure. The most sensitive endpoint is decreased body wei ght. There are no sex differences. There is no apparent target organ. Because toxic effects we re not observed below the limit dose, there is no dose-response. Aminocyclopyrachlor was not geneotoxic, neurotoxic, immunotoxic, or toxic to the reproductive system and did not cause developmen tal toxicity at doses up to the limit dose.

Endpoints have been selected to assess dietary (drinking water), residen tial, and occupational exposures to aminocyclopyrachlor. Toxic ity resulting from a single exposure to aminocyclopyrachlor was not observed, and so quantif ication of acute exposur es is not required. Quantification of dermal exposures is not required because no t oxicity was observed in a dermal study conducted at the limit dose. Endpoints for all inhalation ri sk assessments were selected

Page 8 of 27from oral toxicity studies, and so it is assumed that oral and i nhalation absorption are equivalent. For short and intermediate-term inhalation exposur es an endpoint was selected from a 90-Day Oral Toxicity Feeding-rat (870.3100), citing decr eased body weights, body weight gains, food consumption, and food efficiency in both sexes. Quantification of human carcinogenic risk is not required for aminocyclopyr achlor for this use pattern.

The dose selected for short-term dermal expos ure is a NOAEL of 1000 mg/kg/day. However, aminocyclopyrachlor is not toxic su b-chronically via the dermal rout e of exposure (no toxicity at the limit dose); therefore a dermal assessment was not conducted for this registration action.

Endpoints for all inhalation risk assessments were se lected from oral toxicity studies, and so it is assumed that oral and inhalation absorption are equivalent. For short and intermediate-term inhalation exposures an endpoint wa s selected from sub-chronic toxici ty studies in rats in which decreased body weight was obser ved. A NOAEL of 350 mg/kg/day was selected for short-, and intermediate-term inhalation exposure. A L OAEL of 1045 mg/kg/day wa s selected based on 90- Day Oral Toxicity Feeding-rat (870.3100).

Furthermore, endpoints for short- and intermediate -term incidental oral we re selected based on A NOAEL of 350 mg/kg/day was the do se selected. The LOAEL of 1045 mg/kg/day was selected based on decreased body weights, body weight gains, food consum ption, and food efficiency in both sexes. Quantification of human carcinogenic risk is not required for aminocyclopyrachlor for this use pattern.

The database for acute toxicity for aminocycl opyrachlor-methyl is comple te and is summarized below. Aminocyclopyrachlor-methyl is classifi ed as Toxicity Category IV for acute exposure via the oral, dermal and inhalation routes. Fo r acute ocular, a Toxicity Category of III was established due to mild irritation in white New Zealand rabbits. A summary of the toxicological Categories, doses, and e ndpoints is provided in Tables 3 and 3.1

Table 3: Acute Toxicity of Aminocyclo pyrachlor-methyl ester and potassium salt

Guideline No. Study Type Results Toxicology Category

870.1100 Acute Oral [rat] LD 50 =(comb)-5000 mg/kg IV

870.1200 Acute Dermal [rat] LD 50 =(comb)-5000 mg/kg IV

870.1300 Acute Inhalation [rat] LD 50 > 5.4 mg/L IV

870.2400 Primary Eye Irritation [ra bbit] Mild irritation III

870.2500 Primary Skin Irritation [r abbit] Non-irritant IV

870.2600 Dermal Sensitization [Guinea Pig] Non-sensitizer IV

Page 9 of 27Table 3.1 Summary of Toxicological Doses and Endpoints for Aminocyclopyrachlor-methyl ester and potassium salt

Exposure/ SceNArio Point of Departure Uncertainty/FQPA Safety Factors RfD, PAD, Level of Concern for Risk Assessment Study and Toxicological Effects

IncidentalOral ShortTerm (1-30 days) NOAEL= 350 mg/kg/day UF A = 10 x UF H =10 x Residential LOC for MOE = 100 90-Day Oral Toxicity Feeding-rat (870.3100)

LOAEL = 1045 mg/kg/day (limit

dose) based on decreased body weights, body weight gains, food consumption, and food efficiency in both sexes

Incidental OralIntermediateTerm (1-6

months) NOAEL= 350 mg/kg/day UF A = 10 x UF H =10 x Residential LOC for MOE = 100 90-Day Oral Toxicity Feeding-rat (870.3100)

LOAEL = 1045 mg/kg/day (limit

dose) based on decreased body weights, body weight gains, food consumption, and food efficiency in both sexes

Dermal Short-Term (1-30 days) NOAEL= 1000 mg/kg/day (limit dose) NA NA 28-Day Dermal Toxicity- rat (870.3200)

No hazard was identified.

DermalIntermediateTerm (1-6

months) NOAEL= 1000 mg/kg/day (limit dose) NA NA 28-Day Dermal Toxicity- rat (870.3200)

No hazard was identified.

Inhalation Short- Term (1-30 days) NOAEL=350 mg/kg/day (inhalation and oral are assumed to be

equivalent) UF A = 10 x UF H =10 x Residential/ Occupational LOC for MOE = 100 90-Day Oral Toxicity Feeding-rat (870.3100)

LOAEL = 1045 mg/kg/day (limit

dose) based on decreased body weights, body weight gains, food consumption, and food efficiency in both sexes

InhalationIntermediateTerm (1-6

months) NOAEL=350 mg/kg/day (inhalation and oral are assumed to be

equivalent) UF A = 10 x UF H =10 x Residential/ Occupational LOC for MOE = 100 90-Day Oral Toxicity Feeding-rat (870.3100)

LOAEL = 1045 mg/kg/day (limit

dose) based on decreased body weights, body weight gains, food consumption, and food efficiency in both sexes

Page 10 of 27Note: Point of Departure (POD) = A data point or an estimat ed point that is derived from observed doseresponse 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). FQPA SF = FQPA Safety Factor. PAD = po pulation adjusted dose (a = acute, c = chronic). RfD = reference dose. MOE = margin of exposure. LO C = level of concern. N/A = not applicable

4.0 Occupational Exposure and Risk

Handler Exposure

The proposed uses associated with this action are for use of aminocyclopyrachlor-methyl on noncrops and lawn/turf. Aminocyclopyrachlor, its methyl ester and potassium salt, (4- Pyrimidinecarboxylic acid, 6-amino-5-chloro-2-cycl opropyl, - methyl) is a dispersible granular, a granular and a soluble liquid herbicide used for pr e-, and or post-emergence control of broad leaf and woody species weeds; including many terrestri al, riparian invasive and noxious weeds.

In this registration action aminocyclopyrachlor-m ethyl ester, aminocyclopyrachlor; a potassium salt form, and aminocyclopyrachlor: an acid form , are being registered for general weed and brush control on private, public and military land s including un-cultivated non-agricultural areas such as airports, highways, railroads, golf courses, lumber yards, wild life habitats, multi family residential complexes, recreation ar eas, Sod farms, utility rights of way, and residential lawns.

Based on label specific information and info rmation provided by the registrant, handler exposures are expected to be short- and in termediate-term in duration. The quantitative exposure/risk assessment developed for commerci al handlers is based on the following exposure scenarios:

Groundboom:

• Mixing/loading : (dry flowable, soluble liquid) formul ations to Non-crops, Golf courses, Sod Farms, and Lawn/Turf.

• Applying: (dry flowable, soluble liquid) formula tions to Non-crops, Golf courses, Sod Farms, and Lawn/Turf.

Aerial:

• Mixing/loading : fixed and non-fixed wing (dry flow able) formulation to Non-crops.

• Applying; fixed and non-fixed wing (dry flowable) formulation to Non-crops.

• Flagging : fixed and non-fixed wing (dry flowable) formulation to Non-crops.

LCO Handgun:

• Mixing/Loading : (water dispersible gra nules, soluble liquid) fo rmulation to Non-crops, Golf courses, Sod Farms, and Lawn/Turf.

• Applying : (water dispersible granules, soluble liquid) formulation to Non-crops, Golf courses, Sod Farms, and Lawn/Turf.

Page 11 of 27Right of way Sprayer:

• Mixing/Loading : (water dispersible granules, soluble liquid) formulation to Non-crops, Golf courses, Sod Farms, and Lawn/Turf.

• Applying: (water dispersible granules, soluble liquid) formulation to Non-crops, Golf courses, Sod Farms, and Lawn/Turf.

Push Type Spreader:

• Mixing/Loading: (granular) formulation to Golf cour ses, Sod Farms, and Lawn/Turf.

• Applying: (granular) formulation to Golf c ourses, Sod Farms, and Lawn/Turf.

Tractor Drawn Broadcast Spreader:

• Mixing/Loading/Applying: (granular) formulation to Golf courses, Sod Farms, and Lawn/Turf.

Push Cyclone Spreader

• Mixing/Loading: (granular) formulation to Golf c ourses, Sod Farms, and Lawn/Turf.

No chemical-specific handler exposure data were submitted in support of this registration. It is the policy of the HED to use data from the Pesticide Handlers Exposure Database (PHED) Version 1.1 as presented in PHED Surrogate Exposure Guide (8/98).

As noted in the Executive Summary and Hazar d Profile sections, e ndpoints for short-, and intermediate-term dermal were selected, but a dermal assessment was not conducted, whereas no toxicity was observed.

However, inhalation exposures were calculate d and an assessment was conducted. For all scenarios noted above, MOEs were greater then 100 (MOE >100), and therefore not of concern.

4.1 Data and Assumptions for Occupational Handler Exposure Scenarios

Unit Exposures:

• Chemical-specific data for assessing exposur e during pesticide hand ling activities were not submitted to the Agency in support of this Section 3 application. It is HED policy to use data from the Pesticide Handlers Exposur e Database (PHED) Version 1.1 to assess handler exposures for regulatory actions when chemical-specific data are not available (HED Science Advisory Council for E xposure, SOP Number .007, January 1999).

Page 12 of 27Area Treated:

• HED assumed 40 acres per da y for mixing/ loading, and applying; (lawn/turf/Golf course) with groundboom equipment (HED E xposure Science Advisory Committee SOP Number 9.1)

• HED assumed 80 acres per day for mixing/lo ading, and applying; (Non-crops/sod farms) with groundboom equipment (HED Exposure Science Advisory Committee SOP Number 9.1)

• HED assumed 350 acres for mixing/loading, a pplying and flagging; (Non-crops) with aerial equipment (HED Exposure Scien ce Advisory Committee SOP Number 9.1)

• HED assumed 5.0 acres per day for applica tion; (Non-crop, lawn/turf, golf course, and sod farm ) with LOC Handgun equipment and right of way sprayers (HED Exposure Science Advisory Committee SOP Number 9.1)

• HED assumed 100 acres per day for mixing a nd loading; (Non-crop and lawn/turf) with LOC Handgun equipment.

• HED assumed 5.0 acres per day for loading and applying; (sod farm/ golf course) with a push type spreader (HED Exposure Science Advisory Committee SOP Number 9.1).

• HED assumed 40 acres per day for applicatio n; (sod farm/golf course) with a tractor drawn broadcast spreader, and push cyclone spreader (HED Exposure Science Advisory Committee SOP Number 9.1).

Note: HED maintains that the 100 acres for mixi ng and loading is calculated by assuming the following. (Mixing and loading of 20 trucks that will apply 5 acres of formulation per day).

Application Rate:

Aminocyclopyrachlor is applied in three different formulations, a water dispersible granular, a granular, and a soluble liquid. For this regi stration action DuPont labels, (DPXKJM44 80XP Herbicide/EPA Reg. No. 352 – TOE), (DuPont TM DPX-MAT28 50SG Herbicide/EPA Reg No. 352-TIT), (DuPontTM DPX-MAT28 240SL Turf Herbicide/EPA Reg No. 352-TOG), and (DuPontTM DPX-MAT28 0.064G Lawn Herbicide + Fertilizer/EPA Reg No. 352-TOT), were used because they represented;

• Crop and “Non-Crop” usage

• Conservative maximum application rates applicable to formulation

• Complete exposure scenario explanations (equipment used for application)

The labels noted above specified the distribut ion aminocyclopyrachlor-methyl using a broadcast system (groundboom, right of way sprayer, lawn care operator handgun, push type spreader, push cyclone spreader, tractor drawn spread er, and Aerial fixe d and non-fixed wing)

Page 13 of 27Occupational application rates for all occupati onal equipment range from a minimum of 1.5 oz. of product/ acre per application (0.07 lbs ae/Acre) to a maximum of 9 oz. of product/ acre per season (0.28 lbs ae/Acre).

E xposure Duration:

• MOEs for both the short-term and intermedia te-term scenarios have been estimated.

Body Weight:

• The average adult body weight of 70 kg was usedfor estimating short- and intermediateterm inhalation exposure and risk.

Inhalation Absorption Factor :

• 100%

4.2 Handler Exposure Calculations

Handler risks were calculated using the Margin of Exposure (MOE) which is a ratio of the calculated daily dose to the NOAEL of concern. Daily dose estimates are calculated using relevant application parameters (i.e., rate and area treated) along with unit exposures. Exposures are then adjusted for body weight and absorption factors as appropriate to calculate dose levels. Daily Exposure : The daily exposures were calcu lated as described below.

• Daily exposure = (Unit exposure x appl . rate x Daily Area Treated) Where:

Daily Exposure = Amount (mg ai/day) inhaled that is available for inhalation absorption;
Unit Exposure = Unit exposures (mg ai/lb ai) derived from August 1998 PHED data, or othe r appropriate data;
Application Rate = lbs ai per acre;

Daily Area Treated = acres per day

Daily Dose: The daily dose (inhalation) was calcu lated by adjusting th e inhalation exposure values by body weight and accounting for inha lation absorption. For adult handlers using aminocyclopyrachlor, its methyl ester and potas sium salt an average body weight of 70 kg was used.

Page 14 of 27Page 15 of 27 • Daily Dose = (Daily exposure x absorption factor)/ Bodyweight

Where:

Daily Dose = Absorbed dose (mg ai./kg body weight/day);

Daily Exposure = Amount (mg ai/day) inhaled;

Absorption Factor = 100 % (inhalation)

Body Weight = 70 kg

Margins of Exposure : The daily doses were then compared to the NOAELs to assess the risk as an MOE. The MOEs were calculated using the formula below:

• MOE = NOAEL/Dose Where:

MOE = Margin of Exposure (unit less)

Dose = mg/kg/day

NOAEL = No Observed Adverse Effects Level (mg/kg/day)

4.3 Handler Exposure Summary

Exposure and risk assumptions and MOEs for occupational handlers (A gricultural and NonAgricultural use) are summarized in Table 4

.Table 4: Occupational Short and Intermediate-Term Risk Assessment Uses of Aminocyclopyrachlor-methyl ester and potassium salt

Exposure Scenario Crops Application Rate (lb ae/A) 2 Area Treated (A/day) 3 Inhalation Unit Exposure ( μ g/lb ai) 1 Inhalation Daily Dose (mg/kg/day) 4 Inhalation Short/Intermedia

te-term MOE 5

Open Mixing and Loading Groundboom (dry flowable) 6 0.77 0.0002464 1,400,000

Applying Sprays with Groundboom (Open Cab) (dry flowable) Non-crop 7

. 0.28

0.74 0.0002368 1,500,000

Open Mixing and Loading Groundboom (dry flowable) 6 0.77 0.0000616 5,700,000

Applying Sprays with Groundboom (Open Cab) (dry flowable) Turf 9 /Sod Farm 80

0.74 0.0000592 5,900,000

Open Mixing and Loading Groundboom (Liquid) 0.07

1.2 0.000048 7,300,000

Applying Sprays with Groundboom (Open Cab)

(Liquid) Turf/Lawn Golf Course 2

. 40

0.74 0.0000296 12,000,000

Open Mixing and Loading Groundboom (Liquid) 1.2 0.000096 3,600,000

Applying Sprays with Groundboom (Open Cab)

(Liquid) Turf/Sod Farm 0.07

80

0.74 0.0000592 5,900,000

Mixing/Loading LOC Handgun (dry flowable) Non-crop 0.28 100 8 0.77 0.000308 1,100,000Table 4: Occupational Short and Intermediate-Term Risk Assessment Uses of Aminocyclopyrachlor-methyl ester and potassium salt

Inhalation Application Area Inhalation Inhalation Exposure Scenario Crops Rate Unit (lb ae/A) 2 Treated (A/day) 3 Exposure ( μ g/lb ai) 1 Daily Dose Short/Intermedia (mg/kg/day) 4 te-term MOE 5

Applying LOC Handgun (dry flowable) Non-crop 0.28 5 1.4 0.000028 13,000,000

Mixing/Loading LOC Handgun (Liquid) 100 8 1.2 0.00012 2,900,000

Applying LOC Handgun (Liquid) Turf/Lawn Sod farm Golf Course 0.07

5 1.4 0.000007 50,000,000

Mixing/Loading Aerial (Dry Flowable) 0.77 0.001078 320,000

Applying Sprays Aerial (enclosed Cockpit) (dry flowable) 1.3 0.00182 190,000

Aerial Flagging Non-Crop 7 0.28 350

0.15 0.00021 1,700,000

Mixing /Loading Push Type Spreader (granular) 1.7 0.00001 27,000,000

Applying Push Type Spreader (granular) 5

1.2 0.0000093 38,000,000

Mixing/Loading/Applying Tractor Drawn Broadcast Spreader (granular) Sod farm Golf Course 2 0.108

40 7.3 0.000451 780,000

Applying Right of Way Sprayer (Dry Flowable) Non-Crop 0.28 5 3.9 0.000078 4,500,000

Page 17 of 27Table 4: Occupational Short and Intermediate-Term Risk Assessment Uses of Aminocyclopyrachlor-methyl ester and potassium salt

Inhalation Application Area Inhalation Inhalation Exposure Scenario Crops Rate Unit (lb ae/A) 2 Treated (A/day) 3 Exposure ( μ g/lb ai) 1 Daily Dose Short/Intermedia (mg/kg/day) 4 te-term MOE 5

Mixing/Loading Right of Way Sprayer (Dry Flowable) Non-Crop 0.28 0.77 0.0000154 23,000,000

Applying Right of Way Sprayer (Soluble Liquid) Turf/Lawn/ Sod Farm/Golf

Course 0.07 5

3.9 0.0000195 18,000,000

Note: 1. Inhalation unit exposure values represent no respirator. Values are reported in the PHED Surrogate Exposure Guide dated Aug ust 1998. 2. Application rates are based on maximum values found in proposed labels (ae = acid equivalent) 3. Daily area treated is based on the area or gallons that can be reasonably applied in a single day or “one time application-( non-crop)” for each exposure scenario of concern based on the application method and formulation/packaging type. (standard EPA/OPP/HED values)

. 4. Daily Dose (mg/kg/day) was calculated by Unit Exposure * % Ab sp * Appl. rate * Area treated} / 70 kg. {Where: inhalation ab sp. is assumed to be 100%} Short and Intermediate-t erm endpoints are the same, thus one column. 5. Short-/Intermediate-Term MOE = Inhala tion NOAEL (350 mg/kg/day). The LOC is 100. 6. Note: Open mixing and loading formulation wa s calculated using a “dry-fl owable” exposure scenario. See PHED version 1.1 for de tails. 7. Non-Crop: Weeds /non-agricultu ral item. Max. "Yearly" applica tion label rate for (Non-Crop) on ly: 9 oz./Acre/application.: (9oz./Acre x 1lb/16 oz) x .50% ae = .28 lbs ae/ Ac re) "One time Application" Reference label [352-TIT]

. 8. 100 acres represents an individual mixing and loading 20 trucks that will apply 5 acres 9. Max. Application label rate for (Turf only): 1.5 oz./ Acre/ application.: (1.5oz./Acre x 1lb/16 oz) x .75% ae = .07 lbs ae/ Acre)

Reference label [352-TOE]

5.0 Occupational Post-application Exposure and Risk

This registration action for aminocyclopyrachlor, its methyl ester and potassium salt involves application to agricultura l and non-agricultural crops/non-crops. Chemical-specific post-application exposure data was submitted (MRID # 47560209) in support of this registration action. Turf transferable residues (TTRs), were selected form three test sites lo cated in California (Porterville), Canada (Branchton), and Georgia (Sycamore). 3 At the Georgia site, the average total TTR value was 0.0009 μg/cm 2 at the first post application sampling in terval which took place 2 hours after the application. By the next sampling interval at 1 DAT, total residue s had declined to <LOQ. Based on rainfall data reported in the Study Report, there was a rainfall event almost immediately after application and before the first pos t application sampling (0.02 inches). This appears to have caused rapid dissipation of the residues at the Georgi a site. DPX-KJM44, DPX-MAT28, and total TTR residues were considerably lower than thos e observed at the other two test sites.

3 DFR study: (MRID # 47560209)

Page 18 of 27At the Ontario site, the average total TTR value at the first post application sampling interval was 0.0035μg/cm 2 . Total TTR values declined grad ually to an average of 0.0002 μg/cm 2 by 7 DAT and fell below the LOD by 14 DAT.

At the California site, total TTR values declined rapidly from an average of 0.0070μg/cm 2 at the first post application sampling interval to less than the LOQ by 3 DAT.

Note; at the Georgia site rainfall occurred and cause d substantial lower TTR values, therefore this data was not used in this assessment

. However, as noted earlier quantific ation of dermal exposures is not required because no toxicity was observed in a dermal study conducted at the limit dose.

Furthermore, HED believes that based on the occ upational handler inhalati on MOE values of (190,000 – 50,000,000), occupational post-applica tion inhalation exposures will be negligible and therefore were not assessed in this memorandum. Please see table 4 for specifics.

Aminocyclopyrachlor, its methyl ester and potassium salt are classified in Toxicity Category IV for acute dermal and skin irritation a nd Category III for primary eye irrita tion. The draft product label of (352-TIL- DPX-KJM44 80XP) states that because this product is used on s od farms it is within the scope of the Workers Protection Standard (WPS) for agricultural pesticides (40 CFR Part 170). Therefore the restricted entry interval (REI) is 4 h ours, however due to a toxicology category of III for ocular irritation HED maintains th at a 12 hour REI is appropriate.

5.1 Occupational Post-application Exposure Summary

Quantification of dermal exposures is not required because no toxicity was observed in a dermal study conducted at the limit dose; therefore a dermal post-application assessment was not conducted.

Furthermore, HED believes that based on the occ upational handler inhalati on MOE values range of (190,000 - 50,000,000), occupational post-application i nhalation exposures will be negligible and therefore were not assessed in this memorandum. Please see table 4 for specifics.

6.0 Non-Occupational/Residential Exposure and Risk

Handler Exposure

The proposed uses associated with this action are fo r use of aminocyclopyrachl or, its methyl ester and potassium salt on lawn/turf. Aminocyclopyrach lor-methyl, (4-Pyrimidinecarboxylic acid, 6-amino-5- chloro-2-cyclopropyl, - methyl) are he rbicides formulated as a disper sible granular, a granular, and a soluble liquid for pre-, and or post-emergence c ontrol of broad leaf and woody species weeds; including many terrestrial, riparian invasive, and noxious weeds.

Concerning application use as it app lies to residential exposure and risk ; label specific directions state that the residential use pattern is primarily focused on “residential lawn and turf”. Furthermore the labels noted within (352-TOG, 352-TOE, 352- TOU, 352-TOT, 352-IRG, 352-TOI, 352-IRU, 352- TOO, 352-IRL, 352-INN, 352-ING, 352-INU, 352-INT, 352-IRR, 352-IRE) are comprised of the

Page 19 of 27three different formulations (dispers ible granular, granular, and a sol uble liquid) and all were assessed, however according to label termi nology, the granular formulation seems to be the product most highlighted for residential lawn and turf application.

Based on the number of seasonal ap plications indicated on this pr oduct label (every other month interval), and information provided by the registrant , residential handler exposur es are expected to be short- (1-30 days) and intermedia te-term (1-6 months) in duration. The quantitative exposure/risk assessment developed for residential handlers is based on the following exposure scenarios:

Exposure Scenarios: Open mixing, loading, and applying:

• Low Pressure Handwand (dry flowable and so luble liquid) formulation to Lawn/Turf.

• Hose-end Sprayer (dry flowable and sol uble liquid) formulation to Lawn/Turf.

• Hand Held Spreader [Belly Grinder- (g ranular)] formulation to Lawn/Turf.

Note: Quantification of dermal exposures is not re quired because no toxicity was observed in a dermal study conducted at the limit dose; therefore a dermal assessment was not conducted. However, an inhalation exposure assessment was conducted and noted in table 5

.

6.1 Data and Assumptions for Reside ntial Handler Exposure Scenarios

The data and assumptions are consistent with th e occupational handler section (5.0), however the area treated and unit exposure have been adjusted for residential applications.

Area Treated:

• HED assumed 0.5 acre lawn/turf were treated pe r day while using the following residential equipment (HED Exposure Science Advisory Committee SOP Number 9.1)

.

**o** Low pressure handwand

**o** Hose-end sprayer

**o** Hand Held Spreader (Belly grinder)

Unit Exposures : See table #5 for details.

6.2 Non-Occupational/Residential Handler Exposure Calculations

Please see section 4.0 (Occupationa l Handler Exposure Calculations ), for details.

6.3 Non-Occupational/Residentia l Handler Exposure Summary

Exposure and risk assumptions and MOEs for non- occupational handlers (Non- Agricultural use) are summarized in Table 5

.

Page 20 of 27Table 5: Residential Short and Intermediate-Term Risk Assessment Uses of Aminocyclopyrachlormethyl ester and potassium salt

Exposure Scenario Crops 2 Application Rate (lb ae/A) 3 Area Treated (A/day) 1 Inhalation Unit Exposure ( μ g/lb ai) 5 Inhalation Daily Dose (mg/kg/day) 4 InhalationShort/Intterm MOE

Open Mixing, Loading and Applying Low Pressure Handwand (Soluble Liquid) 30 0.000015 23,000,000

Open Mixing, Loading, and Applying Hose-end Sprayer

(Dry Flowable) .07

17 0.0000085 41,200,000

Open Mixing, Loading, and Applying Belly Grinder

(Granular) Lawn/ Turf

0.10 0.5

62 0.000048 7,300,000

Note: 1. Inhalation unit expos ure values represent no respirator. Values are reported in the PHED Surrogate Exposure Gu ide dated August 1998. 2. Application rates are based on maximum values found in propo sed labels (ae = acid equivalent) daily area treated is based o n the area or gallons that can be reasona bly applied in a single day for ea ch exposure scenario of concern based on the application method and formulation/packaging type. (S tandard EPA/OPP/HED values). 4. Short-/Intermediate-Term MOE = Inhalation NOAEL (350 mg/kg/day). The LOC is 100. 5. Note. Daily Dose (mg/kg/day) was calculated by Unit Exposure * % Absp * A ppl. rate * Area treated} / BW-70 kg. {Where: inha lation absp. is assumed to be 100%} Short and Intermedia te-term endpoints are the same, thus one column.

7.0 Non-Occupational/Residential Post-application Exposure and Risk

A wide array of individuals of varying ages can potentially be exposed to aminocyclopyrachlor, its methyl ester and potassium salt, when they do activi ties in areas that has been previously treated. Post-application exposure scenarios were de veloped for each residential setting where aminocyclopyrachlor, its methyl ester and potassium salt can be used. Current label guidelines state that treatment is to occur at residential homes and multi family residential complexes.

7.1 Data and Assumptions for Non-Occupationa l/Residential Handler Exposure Scenarios

• Residential exposure assessments for aminocyc lopyrachlor, its methyl ester and potassium salt were classified as short-, and intermediate -term exposure scenarios due to the number of seasonal applications.

• Dermal exposures for children as well as adults were not assessed.

Page 21 of 27• Non-dietary ingestion exposures to toddlers were calculated (i .e., soil ingestion, hand-/objectto-mouth).

• Body weight use for calculations (15kg/day). HED relies on a standardized approach for completing residential risk assessments that is based on current aminocyclopyrachlor labels.

• Standard Operating Procedures for Resi dential Exposure A ssessment (Dec. 1997). This document provides the overarching guidance fo r developing residential risk assessments including scenario development, algorithms, and values for inputs.

7.2 Post-Application Dermal Exposure

As note in previous sections, a quantification of de rmal exposures is not re quired because no toxicity was observed in a dermal study conducted at the lim it dose; therefore a dermal assessment was not conducted. However, an incidental oral (hand to mouth, object to mouth, and soil ingestion) exposure assessment was conducted and noted below in table 6

. Chemical-specific post-application exposure data was submitted (MRID # 47560209) in support of the registration of aminocyclopyrachlor, its methyl ester and potassium salt. Turf transferable residues (TTRs), were selected form three test sites located in California (Porterville), Canada (Branchton) and Georgia (Sycamore). Note; at the Georgia site rainfall occurred and caused substantial lower TTR values, therefore this data wa s not used in this assessment

.

7.3 Post-Application Incidental Oral Exposure

Incidental Oral exposure was assessed for toddlers. Please table 6 for details.

7.3.1 Incidental Oral Exposure Calculations

Non-dietary Ingestion Exposure from Treated Turf: Non-dietary ingesti on exposure from treated turf was calculated using the following equations.

• Hand-to-mouth Transfer of Pesticid e Residues on Lawns (toddler)

The approach used to calculate th e non-dietary ingestion exposures that are attributable to hand-tomouth behavior on treated turf is: ADD = (TTR 0 * SA * FQ * ET * SE * CF1) / BW Where:

ADD = average daily dose (mg/kg/day);

TTR t = turf transferable residue on day "0" ( μ g/cm 2 );

SA = surface area of the hands (20 cm 2 /event);

Page 22 of 27FQ = frequency of hand-to-mouth activity (Short-term 20/Intermediate-term 9.5 events/hr);

ET = exposure time (2 hr/day);

SE = extraction by saliva (50%);

CF1 = weight unit conversion factor to convert μ g units in the DFR value to mg for the daily exposure (0.001 mg/ μ g); and

BW = body weight (15 kg).

• Object-to-mouth Transfer of Pesticide Residues on Lawns (toddler)

The approach used to calculate exposures that are attributable to object-to -mouth behavior on treated turf that is represented by a child mouthing on a handful of turf is:

ADD = (TTR 0 * IgR* CF1) / BW

Where:

ADD = average daily dose (mg/kg/day);

TTR t = turf transferable residue on day "0" ( μ g/cm 2 );

IgR = ingestion rate of grass (25 cm 2 /day);

CF1 = weight unit conversion factor to convert the μ g of residues on the grass to mg to provide units of mg/day (1E-3 mg/ μ g);

BW = body weight (15 kg).

• Incidental Ingestion of Soil from Pestic ide-Treated Residential Areas (toddler).

The approach used to calculate exposures th at are attributable to soil ingestion is:

ADD = (SR 0 * IgR * CF1) / BW

Where:

ADD = average daily dose (mg/kg/day);

SR 0t = soil residue on day "0" (0.0022 μ g/g);

Page 23 of 27IgR = ingestion rate of soil (100 mg/day);

CF1 = weight unit conversion factor to convert the μ g of residues on the soil to grams to provide units of mg/day (1E-6 g/ μ g); and

BW = body weight (15 kg).

7.4 Non-Occupational/Residential Post-Application Exposure Summary

Detailed risk calculations for the various residen tial aminocyclopyrachlor asse ssments are included in Appendices D. A summary of risk estimates for residential post-application risks for children is provided in table 6

. Additionally, HED combines risk values resulting from separate post-application exposure scenarios when it is likely they can occu r simultaneously based on the use-pattern and the behavior associated with the exposed population (see Table 6 ).

Table 6: Toddler Residential Risk Estimates for Pos t-application Exposure to Am inocyclopyrachlor-methyl ester and potassium salt

Exposure Scenario TC cm2/hr Route of Exposure Application Rate 5 MOE at Day 0 1 Combined MOE Ingestion
Outdoors S-Term Int-Term

2 Hand to Mouth Activity on Turf 234,000 493,000

3 Object to Mouth Activity on Turf 938,000

4 Soil Ingestion N/A Oral 0.1

70,000,000 322,000

1Combined MOE = NOAEL/ (ADD hand-to-mouth + ADD object-to-mouth + ADD incidental soil ingestion ) Intermediate.-term ADD us ed to calculate combined MOE: (most conservative ) : Level of Concern: MOE = 100

2 Hand-to-mouth Transfer of Pesticid e Residues on Lawns (toddler): ADD = (TTR 0 * SA * FQ * ET * SE * CF1) / BW * FQ: (Short-term 20/Intermediate-term 9.5 events/hr);

3 Object-to-mouth Transfer of Pestic ide Residues on Lawns (toddler): ADD = (TTR 0 * IgR* CF1) / BW 4 Incidental Ingestion of Soil from Pes ticide-Treated Residential Areas (toddler ): ADD = (SR 0 * IgR * CF1) / BW 5 Short-/Intermediate-Term MOE = Inhalation NOAEL (350 mg /kg/day). The LOC is 100.

8.0 Conclusion

This registration action for aminocyclopyrachlor, its methyl ester and potassium salt involves application to non-agricultural crops , exclusively (Lawn/Turf). Ch emical-specific post-application exposure data was submitted (MRID # 47560209) in support of the registration of aminocyclopyrachlor, its methyl ester and potassium salt. Turf transferable residues (TTRs), were selected form three test sites located in Califor nia (Porterville), Canada (Branchton), and Georgia (Sycamore). Note; at the Georgi a site rainfall occurred and caus ed substantial lower TTR values, therefore this data was not used in this assessment

. However, as noted earlier quantification of dermal exposures is not required because no toxicity was observed in a dermal study conducted at the limit dose.

Page 24 of 27Page 25 of 27 For all Occupational and Non-O ccupational/Residential handler and post application exposure scenarios, Margins of Exposure (MOEs) were ≥ 100 and therefore risks we re not observed at these application rats.

Lastly, label directions call for a re stricted entry interval (REI) of 4 hours, however due to a category III in acute eye irritation, HED maintains that a REI of 12 hours is appropriate and that all label directions reflect this change.9.0 References

• Label Use Patterns; (EPA registration #’s 352-TOG, 352-TOE, 352-INN, 352-TOT, 352- IRL, 352-IRE, 352-TOU, 352-TIA, 352-TIL, 352-TIT, 352-IRG, 352-IRU, 352-TOO, 352- ING, 352-INU, 352-INT, 352-IRR, 352-TOI)

• Pesticides Handlers Exposure Database (P HED)Version 1.1; dated 8/98 (HED Science Advisory Council for Exposure Draft Policy #7; dated 1/28/99

• End Point Selection; [(see Memorandum, DP # 369507 titled, Aminocyclopyrachlor: Human Health Risk Assessment for Proposed Us es as an Herbicide. PC Code: 288008, 288009, 288010 DP Barcode: D369057

• HED: Exposure Science Advisory Counsel

• Chemical-specific post-applica tion exposure data, (MRID # 47560209).

Page 26 of 27Page 27 of 27 

## Appendices

A) Commercial Handler (inhalation

B) Residential Handler (inhalation)

C) Residential Post-Applic ation (Incidental Oral)