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

OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION



### MEMORANDUM

Date:

S ubject: August 4

, 2015

Triclopyr. Occupational and Residential Exposure Assessment for a Reevaluation of Ex i sting Residential Uses with the Updated Residential
Standard Operation Proc edures (SOPs).

P C Code: I 1 6000

, I 16001

, 116002, 1 1 6004 Deci s ion No.: 488478 DP Barcode: 0426070
R eg i strat ion No.: 62719

- 37

, 627 1 9-53

, 62719-87

, 627 I 9-552

, 627 I 9 -6 37

, 627 I 9-A I T(687) Regulator y Action: Section 3 Petition No.: 4F8249

, 4F8279
Risk Assess m e n t Type: Case No.: 2710 Occupationa l/ Residential Exposure Assessment
TXRNo.: NA CAS No.: 55335-06-3, 572 13- 69-1, 64700-56-7

, /



### FROM: Lata Venkates hw ara , Environmental Scientist 1048373-85

- 8**w~** 40CFR: §180.417 

### \)tr\..

# l-rMRID No.: NA



### Jenni fer R. Tyler, Chemist**~ ~~J**  

### /

....,_

_____ ___ 

### Risk Assessment Branch 1 (RAB I)

## ~**~** Health Effects Division (HE D ; 7509P)



### THROUGH: Kelly M. Lowe

, Environmental Scientist**-~ ~**  

### Charles Smith, Branch Chief 

# Cf'"**~ ~**  

### RAB1/HED(7509P)**~**



### TO:

Introduction Mindy Ondish

, Risk Reviewer
Reuben Baris, Product Manager 25
Herbicide Branch ( HB )
Re gistration Division (RD, 7505P)

RD forwarded an action to HED for triclopyr that included: 1) the removal of a grazing

r estr icti on for lactating dairy cattle, and the estab li shment of milk and milk fat tolerances;
and 2) the registration of triclopyr choline salt for use on all ex i sting registered uses. Ne i ther
of these actions is anticipated to r equi r e a quantitative occupational exposure assessment si nc e no new uses are being requested. The rates for t ricl opyr choline salt on existing registered uses are no higher than what was assessed prev i ously, so no new assessments are required. No new residential uses are being requested eit h er; however

, since

_ a revised dietary assessment is required to incorporate the new tolerances

, a reevaluation of ex i st i ng

Page 1 of 17

### Page 2 of 17 triclopyr residen tial uses has been performed for inclusion in an updated aggregate assessment. The reevaluation reflect s updates to HED’s 2012 Residential Standard Operating Procedures (SOPs) along with policy changes for body weight assumptions.

It is HED policy to use the best available data to assess exposure. Several sources of generic data were used in this assessment as surrogate data in the absence of chemical

- specific data, including the Pesticide Handlers Exposure Database Version 1.1 (PH ED 1.1); the Agricultural Handler Exposure Task Force (AHETF) database; the Outdoor Residential Exposure Task Force (ORETF) database ; and the Residential SOPs ( Lawns/Turf )

. Some of these data are proprietary, and subject to the data protection provisions o f the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).

### Page 3 of 17 Table of Contents

1.0 Executive Summary

................................ ................................ ................................ ....... 4 2.0 Risk Assessment Conclusions and Recommendations

................................ .................. 6 2.1 Summary of Risk Estimates

................................ ................................ ....................... 6 2.2 Label Recommendations from Occupational/ Residential Assessment

..................... 6 2.3 Data Deficiencies and Requirements

................................ ................................ ......... 6 3.0 Hazard Characterization

................................ ................................ ................................ . 6 4. 0 Proposed Use Profile

................................ ................................ ................................ ...... 9 5.0 Residential Exposure and Risk Estimates

................................ ................................ ...... 9 5.1 Residential Handler Exposure/Risk Estimates

................................ ......................... 10 5.2 Residential Post

- application Exposure/Risk Estimates

................................ ............ 11 5.3 Residential Risk Estimates for Use in Aggregate Assessments

............................... 12 5.4 Spray Drift

................................ ................................ ................................ ............ 14 5.5 Residential Bystander Post

- Application Inhalation Exposure

.............................. 14 6.0 Occupational Exposure and Risk Estimates

................................ ................................ 14

### Page 4 of 17 1.0 Executiv e Summary

This document presents a reevaluation of existing triclopyr residential uses to support a submitted action that includes: 1) the removal of a grazing restriction for lactating dairy cattle and the establishment of milk and milk fat tolerances; and 2) the registration of triclopyr choline salt for use on all existing registered uses

. Neither of these actions is anticipated to require a quantitative occupational exposure assessment since no new uses are being requested. The rates for triclopyr c holine salt on existing registered uses are no higher than what was assessed previously, so no new assessments are required.

The proposed actions will not result in new residential exposure s ; ho wever, the currently registered turf and aquatic use have bee n reassessed in this document to reflect updates to
HE D’s 2012 Residential SOPs along with policy changes for body weight assumptions . The residential exposures have been revised since they will impact the aggregate assessment for triclopyr

.

U se Profile : Triclopyr, triclopyr TEA, and triclopyr BEE products are used as selective herbicides to control broadleaf weeds and woody brush . Triclopyr products are registered for use on rice as well as a variety of terrestrial non

- agricultural sites ( rights of way, pasture and rangelands, forests, and turf including home lawns, golf courses, and athletic fields ) and aquatic sites (lakes, ponds, reservoirs, and wetlands) . Triclopyr products are formulated as soluble concentrates, emulsifiable concentra tes, liquids (pressurized and ready

- to

- use), granules, wettable powders, and pellets.

Exposure Profile : While occupational exposures are anticipated from the proposed triclopyr choline salt uses, a quantitative assessment has not been conducted since t he rates for these uses are not higher than w hat has already been assessed.

T he registered residential uses (turf and aquatic use) result in handler inhalation and post

application inhalation and ingestion exposures for adults, post

- application inhalation and ingestion exposure for children (3 to <6 years old), and post

- application incidental oral exposures for children (1 to <2 years old). The dermal route of exposure is not quantitatively assessed because there is no dermal hazard. Short

- term exposures are anticipated for residential handlers, while short

- and intermediate

- term residential post

- application exposures are expected. Chronic exposures are not anticipated.

Hazard C haracterization : A short

- term dermal endpoint was not selected since there were no adverse dermal or systemic effects observed in a 28

- day dermal study in rats. D ermal endpoints were previously selected for the intermediate

- and long

- term scenarios for triclopyr ; however

, a reevaluation of the available data indicates that the toxicity profile for triclopyr does not show progression of toxicity with increased duration. HED identified short

- and intermediate

- term inhalation and incidental oral toxicological points of depar ture (PODs) . The no

- observed adverse

- effect level (NOAEL) for short

- and intermediate

- term inhalation and incidental oral exposure is 5 mg/kg/day. Triclopyr is classified as “not likely to be carcinogenic to humans.” HED’s level of concern (LOC) for non

- cancer risks (i.e., LOC for Margins of Exposure (MOEs) ) is defined by uncertainty factors. HED applies a

### Page 5 of 17 10X factor to account for inter

- species extrapolation and a 10X factor to account for intra

species variation. The subchronic inhalation study is re quired at this time, and an additional 10X database uncertainty factor will be applied for assessment of inhalation exposure scenarios. The total uncertainty factor that is applied to inhalation risk assessments is 100 0 X for short

- and intermediate

- term r isks , while the factor applied to incidental oral risk assessments is 100x for short

- and intermediate

- term risks

.
Residential Exposure and Risk Estimates : The results of the residential handler exposure and risk assessment indicate that short

- term inhalation risks are not of concern (i.e. MOE s ≥ 1000) for all turf scenarios

. Short

- term incidental oral post

- application risk estimates for all turf scenarios ar e not of concern to HED ( i.e., MOEs ≥ 100 ) . S hort

- term incidental oral post

application risk estimates are protective of intermediate

- term because the POD is the same.

Short

- term inhalation post

- application risk estimates for all swimmer scenarios are not of concern to HED ( i.e., MOEs ≥ 1000 ) . Furthermore, short

- term inhalation post

- application risk estimates are protective of intermediate

- term because the POD is the same. T he post

application ingestion risk estimates for swimmers are also not of conc ern to HED ( i.e., MOE s ≥ 100 )

.
Occupational Exposure and Risk Estimates : The proposed action to remove a grazing restriction for dairy cattle is not expected to result in occupational exposures; and the proposed registration of the choline salt is covered by the previous actions. As a result, no new occupational assessments have b een conducted for these actions. However, occupational handler inhalation exposure and risk estimates were updated to reflect all of the currently registered uses of triclopyr for the July 2014 HASPOC meeting in order to assess the inhalation waiver reque st submitted by the triclopyr registrants. Besides mixer/loader for aerial applications to forestry, all occupational inhalation MOEs are 1,200

- 180,000. For mixers/loaders of the liquid formulation for aerial application by helicopter to forestry, the in halation MOE is 41 (see Table 6.1).

Human Studies Review : This risk assessment relies in part on data from studies in which adult human subjects were intentionally exposed to a pesticide or other chemical. These data, which include Pesticide Handlers Exposure Database Version 1.1 (PHED 1.1); the Agricultural Han dler Exposure Task Force (AHETF) database; the Outdoor Residential Exposure Task Force (ORETF) database; and the Residential SOPs (Lawns/Turf ; Aquatic
Use ), are (1) subject to ethics review pursuant to 40 CFR 26, (2) have received that review, and (3) are compliant with applicable ethics requirements. For certain studies, the ethics 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 the Agency website 1



### .

1 http://www.epa.gov/pesticides/science/handler

- exposure

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

- app

- exposure

- data.html

### Page 6 of 17 2.0 Risk Assessment Conclusions and Recommendations

2.1 Summary of Risk Estimates

Occupational Exposure and Risk Estimates : The proposed action to remove a grazing restriction for dairy cattle is not expected to result in occupational exposures; and the

pro posed registration of the choline salt is covered by the previous actions. No new occupational assessments have been conducted.

Residential Exposure and Risk Estimates : There are no risk estimates of concern for all registered residential uses of tricl opyr.

2.2 Label Recommendations from Occupational/ Residential Assessment

No label recommendations are required at this time

.

2. 3 Data Deficiencies and Requirements

There are no data deficiencies or data requirements for the proposed new use of triclopyr.

3 .0 Hazard Characterization

Acute Toxicity : The acute toxicity categories are presented in Table s 3.1

- 3.3

.

Table 3.1 . Acute Toxicity Profile

– Triclopyr Acid.

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

870.1100 Acute oral 00031940 LD 50 = 729 mg/kg (M)
LD 50 = 630 mg/kg (F) III

870.1200 Acute dermal 00056009 LD 50 > 2000 mg/kg III

Table 3.2 . Acute Toxicity Profile

– Triclopyr Triethylamine Salt.

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

870.1100 Acute oral 41443301 LD 50 = 1847 mg/kg III

870.1200 Acute dermal 41443302 LD 50 > 2000 mg/kg III

870.1300 Acute inhalation 41443303 LC 50 > 2.6 mg/L III

870.2400 Primary eye irritation 41443304 corrosive I

870.2500 Primary skin irritation 41443305 not irritating IV

870.2600 Dermal sensitization 41443306 sensitizer

--

### Page 7 of 17 Table 3.3 . Acute Toxicity Profile

– Triclopyr Butoxyethyl Ester.

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

870.1100 Acute oral 40557004 LD 50 = 803 mg/kg III

870.1200 Acute dermal 40557005 LD 50 > 2000 mg/kg III

870.1300 Acute inhalation 40557006 LC 50 > 4.8 mg/L III

870.2400 Primary eye irritation 40557007 minimally irritating III

870.2500 Primary skin irritation 40557008 not irritating IV

870.2600 Dermal sensitization 40557009 sensitizer

--



### Toxicological PODs Used for Risk Assessment : The bioequivalency of the three chemical forms of triclopyr (acid, triethylamine salt, and butoxyethyl ester) has been addressed through a variety of special studies with the salt and ester forms, including data on comparative disposition, plasma half

- life, tissue distribution, and hydrolytic cleavage. These studies were found to adequately address the issue of bioequivalency

. In addition, in a memo dated 22

- MAR

- 2012, HED reviewed a request to determine the bioequivalence between triclopyr and triclopyr choline salt, and agreed that bioequivalence was supported by the currently available information (Memo, G. Kramer, D399410). Therefore , studies conducted with any one for m of triclopyr have been used to support the toxicology database as a whole.

Triclopyr has been classified as having low acute toxicity via the oral, dermal and inhalation routes (Toxicity Category III

- IV). The salt form was found to be corrosive to th e eye, while the ester form was only minimally irritating. Both the salt and ester forms of triclopyr were found to be dermal sensitizers, but not a dermal irritant.

Waivers have been submitted by the registrant for the acute neurotoxicity (ACN) and subc hronic inhalation studies. The HED Hazard and Science Policy Council (HASPOC) discussed the need for these studies using a WOE approach (J. Leshin; TXR# 0057009). HASPOC concluded that the ACN is not required at this time. The subchronic inhalation stud y is required at this time, and an additional 10X database uncertainty factor will be applied for assessment of inhalation exposure scenarios.

The toxicity endpoi nts and the PODs for various exposure scenarios are presented in Table s 3. 4 and 3.5.

Table 3.4. Summary of Toxicological Doses and Endpoints for Triclopyr for Use in Dietary and Non

Occupational Human Health Risk Assessments

.
Exposure/ Scenario Point of Departure Uncertainty/F QPA Safety

Factors RfD, PAD, Level of Concern for Risk Assessment Study and Toxicological Effects

Acute Dietary (General Population including infants and children) NOAEL = 100 mg/kg/day UF A = 10X
UF H = 10X FQPA = 1X aRfD = 1.0 mg/kg/day

aPAD = 1.0 mg/kg/day Developmental Rat Toxicity Study with ester Maternal LOAEL = 300 mg/kg/day based on mortality (other effects seen at this dose included clinical signs, necropsy findings, decreased food and water consumption, and increased kidney and liver weights ).

### Page 8 of 17 Table 3.4. Summary of Toxicological Doses and Endpoints for Triclopyr for Use in Dietary and Non

Occupational Human Health Risk Assessments

.
Exposure/ Scenario Point of Departure Uncertainty/F QPA Safety

Factors RfD, PAD, Level of Concern for Risk Assessment Study and Toxicological Effects

Acute Dietary (Females 13

- 50 years old) NOAEL = 5 mg/kg/day UF A = 10X
UF H = 10X FQPA = 1X aRfD = 0.05 mg/kg/day

aPAD = 0.05

mg/kg/day Two

- Generation Rat Reproduction Study with acid LOAEL = 25 mg/kg/day based on increased incidence of rare malformations (exencephaly and ablepharia)

Chronic Dietary (All Populations) NOAEL = 5 mg/kg/day UF A = 10X
UF H = 10X FQPA = 1X cRfD = 0.05 mg/kg/day

cPAD = 0.05

mg/kg/day Two

- Generation Rat Reproduction Study with acid LOAEL = 25 mg/kg/day based on degeneration of the proximal renal tubules
Incidental Oral Short

- Term (1

- 30 days) and Intermediate

Term (1

- 6 months) NOAEL = 5 mg/kg/day UF A = 10X
UF H = 10X FQPA = 1X Residential LOC for MOE = 100 Subchronic Oral Rat Toxicity Study with acid LOAEL = 20 mg/kg/day based on degeneration of the proximal renal tubules

Dermal Short

- Term (1

- 30 days) and Intermediate

Term (1

- 6 months) No hazard was identified for dermal exposure; therefore a quantitative dermal assessment is not needed.

Inhalation Short

- Term (1

- 30 days) and Intermediate

Term (1

- 6 months) NOAEL = 5 mg/kg/day

Inhalation assumed equivalent to oral UF A = 10X
UF H = 10X FQPA = 10X Residential LOC for MOE = 1000 Subchronic Oral Rat Toxicity Study with acid LOAEL = 20 mg/kg/day based on degeneration of the proximal renal tubules

Cancer (oral, dermal, inhalation) Classified as a “ Group D Chemical

– unable to be classified as to human carcinogenicity”

Point of Departure (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 (i nterspecies). UF H = potential variation in sensitivity among members of the human population (intraspecies). UF L = use of a LOAEL to extrapolate a NOAEL. FQPA SF = FQPA Safety Factor. PAD = population adjusted dose (a = acute, c = chronic). RfD = refe rence dose. MOE = margin of exposure. LOC = level of concern.

### Page 9 of 17 Table 3.5. Summary of Toxicological Doses and Endpoints for Triclopyr for Use in Occupational Human Health Risk Assessments

Exposure/ Scenario Point of Departure Uncertainty Factors Level of Concern for Risk Assessment Study and Toxicological Effects

Dermal Short

- Term (1

- 30 days) and Intermediate

Term (1

- 6 months) No hazard was identified for dermal exposure; therefore a quantitative dermal assessment is not needed.

Inhalation Short

- Term (1

- 30 days) and Intermediate

Term (1

- 6 months) NOAEL = 5 mg/kg/day

Inhalation assumed equivalent to oral UF A = 10X
UF H = 10X
UF DB = 10X Occupational LOC for MOE = 1000 Subchronic Oral Rat Toxicity Study with acid LOAEL = 20 mg/kg/day based on degeneratio n of the proximal renal tubules

Cancer (oral, dermal, inhalation) Classified as a “ Group D Chemical

– unable to be classified as to human carcinogenicity”

Point of Departure (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 obse rved adverse effect level. LOAEL = lowest observed adverse effect level. UF = uncertaint y factor. UF A = extrapolation from animal to human (interspecies). UF H = potential variation in sensitivity among members of the human population (intraspecies). UF L = use of a LOAEL to extrapolate a NOAEL. MOE = margin of exposure. LOC = level of concern.



### Body Weight : The standard body weight for the general population (80 kg) was used for all exposure scenarios covered in this risk assessment since the endpoints selected were not developmental and/or fetal effects.

4 .0 Proposed Use Profile

The current actions for t riclopyr include the 1) removal of a grazing restriction for lactating dairy cattle and the establishment of milk and milk fat tolerances; a nd 2) the registration of triclopyr choline salt for use on all existing registered uses. Neither of these actions is anticipated to require a quantitative occupational exposure assessment since no new uses are being requested. No new residential uses are being requested either; however, since a revised dietary assessment is required to incorporate t he new tolerances, a reevaluation of existing triclopyr residential uses has been performed for inclusion in an updated aggregate assessment. The reevaluation reflect s updates to HED’s 2012 Residential SOPs along with policy changes for body weight assump tions.

5 .0 Residential Exposure and Risk Estimates

The proposed uses do not involve applications by homeowners or commercial applicators in residential settings. Therefore, no new residential exposure is expected. However, there are existing residentia l uses that have been reassessed in this document to reflect updates to HED’s 2012 Residential SOPs ( http://www.epa.gov/pesticides/science/residential

- exposure

sop.html ) al ong with policy changes for body weight assumptions. The revision of residential exposure estimates will impact the human health aggregate risk assessment for triclopyr.

### Page 10 of 17 Triclopyr is registered for use on several terrestrial non

- agricultural use sites in cluding rights

of

- way, pasture and rangelands, forests, and turf, including home lawns golf courses and athletic field

. The residential lawn uses include spot and broadcast applications. It is also used in aquatic settings to control aquatic weeds growing in lakes, ponds, reservoirs, and wetlands, and to control woody brush and herbaceous weeds in wetlands and on the banks and shores of aquatic sites.

According to the most recent scoping document, th ere are hundreds of pr oducts that contain triclopyr, triclopyr salts, and triclopyr esters. HED focused on a subset of these labels that covered a majority of the uses in order to identify relevant use sites and application rates for this reassessment

. Table 5.0.1 below summ arizes the scenarios and rates assessed.

Table 5.0.1. Summary of Relevant Residential Use Patterns for Reevaluation

Chemical

Name Registration Number and Product Name Use Site Formulation and Percent Active Ingredient Application method Maximum App Rate

Triclopyr triethylamine salt (116002) 62719

- 226 Dow AgroSciences Brush & Weed

Herbicide For the control of woody plants, vines and broadleaf weeds around homes, cabins, fences, walkways and other non

- crop areas. Contains Hammer Herbicide. This product is for outdoor residential use only. Soluble Liquid (SL) 8.8% Ground, hose end sprayer, tank type sprayer, backpack

sprayer 9 lb ae/A

0.0375 lb ae/gal

0.0096 lb ae/ ft 2

Triclopyr, butoxyethyl

ester (116004) 62719

- 566 Turflon Ester Ultra Golf course turf, ornamental lawn and turf EC 60.5% Ground (sprayer) 1. 5 lb a e /A

Triclopyr triethylamine salt (116002) 62719

- 187
Renovate * Aquatic areas/water SL 44.4 % Spray boom, handgun, or other suitable equipment mounted on a boat or vehicle,

helicopter. 6 lb ae/A

( equivalent to 0.552 mg/L water concentration )



### Residential handler assessments were only conducted for the turf uses, and not the aquatic use sites because the aquatic sites are not residential in nature and homeowner applications are unlikely. It is noted that the aquatic label includes the following statements which imply commercial/professional applications: (1) state and/or local authorities are to be consulted prior to applying this product to public waters ; and (2) State or local public agencies may require permits.

5.1 Residential Handler Exposure/Risk Estimates

Summary of Residential Handler Non

- Cancer Exposure and Risk Estimates Residential handler assessments were only conducted for the turf uses, and not the aquatic use sites because the aquatic sites are not residential in nature and homeowner applications

### Page 11 of 17 are unlikely. It is noted that the aquatic label includes the following statements which imply commercial/professional applications: (1) state and/o r local authorities are to be consulted prior to applying this product to public waters ; and (2) State or local public agencies may require permits. Table 5.0.2 presents the residential handler exposures and risks for triclopyr, triclopyr TEA and triclopy r BEE.

Table 5. 0.2 . Residential Handler Exposure and Risk for T riclopyr, Triclopyr TEA, and Triclopyr BEE

.

Exposure Scenario Application Rate a Amount Handled b Unit Exposure (mg/lb ai) b Dose (mg/kg/day) d MOE e (LOC =

1000)

Baseline Inhalation c Baseline Inhalation Baseline Inhalation

Mixing/Loading/Applicator

– Turf

Mixing/Loading/Applying Liquids with Hose End Sprayer 9 lb a e /acre 0.5 acres 0.022 0.0012 4,000

Mixing/Loading/Applying Liquids with Manually Pressurized Handwand 0.0375 lb a e /gal 5 gallons 0.018 0.000042 120,0 00

Mixing/Loading/Applying Liquids with S prinkler C an 0.0096 lb

a e / ft 2 1000 ft 2 0.022 0.0026 1,900

Mixing/Loading/Applying Liquids with
B ackpack 0.0375 lb ae/gal 5 gallons 0.14 0.0 0033 15,000

a. Application rate based on label Dow AgroSciences Brush &Weed Herbicide ( Reg. No. 62719

- 226)

. b. Unit exposure values and estimates for area treated or amount handled based on Exposure Science Advisory Council 2012 Residential SOPs: http://www.epa.gov/pesticides/science/residential

- exposure

- sop.html

c. Baseline Inhalation: no respirator. d. Inhalation Dose (mg/kg/day) = daily unit exposure (mg/lb a e ) * application rate (l b a e / unit volume or area ) * amount handled ( unit volume or area ) * inhalation absorption (100%) / body weight (80 kg).

e

. MOE = NOAEL (short

- term inhalation = 5 mg/kg/day) / daily dose (mg/kg/day). LOC = 100 0

.


### 5 .2 Residential Post

- application Exposure/Risk Estimates

Summary of Residential Post

- Application Non

- Cancer Exposure and Risk Estimates Table 5. 0.3 presents the post

- application incidental oral MOE values calculated f or the broadcast liquid application of t riclopyr, triclopyr TEA, and triclopyr BEE to turf. The post

application MOEs for hand

- to

- mouth, object to mouth and soil ingestion are not of concern to HED (MOEs range from 22 0 to 98,000 ).

Table 5. 0. 3

. Residential Post

- application Non

- cancer Exposure and Risk Estimates for T riclopyr, T riclopyr TEA, and
T riclopyr BEE

. Lifestage Post

- application Exposure Scenario Application Rate a Dose (mg/kg/day) b MOEs c (LOC = 100) Use Site Route of Exposure

Child (1 to <2 years old) Liquid Application to Turf ST Hand

- to

- Mouth
1.5 lb ae/acre 0.0228 220
ST Object

- to

- mouth 0.00069 7,200
ST/IT Soil Ingestion 5.1 E

- 0 4 98,000

a Based on label Dow AgroSciences Turflon Amine (Reg. No. 62719

- 2 57 ). b Dose (mg/kg/day) equations (see Appendix B)

c MOE = NOAEL ÷ Daily Dose (mg/kg/day). ST/IT Incidental Oral and Inhalation NOAEL = 5 mg/kg/day. Level of concern = 100.



### Tables 5 .0

. 4 and 5.0. 5 provide the post

- application inhalation and ingestion risk estimates for

expo sure of swimmers to triclopyr.

### Page 12 of 17 Table 5. 0. 4 . Short

- Term Post

- application Exposure

- Inhalation of Water by Swimmers

.

Exposure Scenario Cw 1 (mg/L) I R 2 (L/hr) ET 3 (hr/day) BW 4 ( kg) Exposure 5 Absorbed Dose 6 (mg/kg/day) MOE 7 (LOC =

1000)
S wimmer; adult 0.552 0.64 0.025 80 9.1E

- 05 1.14E

- 06 4,400,000
S wimmer; child (3 to <6 years old) 0.42 0.076 19 1.8E

- 04 9.55E

- 06 520,000

1 Cw = concentration in water is based on the application rate provided on the product label. An assumption of 4 feet depth (and uniform distribution) was used to estimate the concentration in water

. 2 I R = inhalation of water ; based on the Risk Assessment Guidance for Superfund ( RAGS) Part A ( http://www.epa.gov/oswer/riskassessment/ragsa/ ) which references a value from the Superfund Exposure Assessment Manual (USEPA, 1988). The recommended point estimate for use in po st

- application incidental ingestion exposure assessments is 0.05 L/hr of swimming for adults and children 3 to < 6 years old.

3 ET =exposure time; based on 2011 E xposure F actors H andbook (Table 16

- 20)

. 4 BW = body weight; based on the Residential Pestic ide Exposure Assessment SOP ( February

- 2012).

5 Exposure = ( VV pp * IR * ET )

6 Absorbed Inhalation dose = (E x AF) ÷ BW

7 MOE = NOAEL ( 5 mg/kg/day; adult and child) ÷ dose (mg/kg/day)

Table 5. 0 .5 . Short

- Term Post

- application Exposure

- Ingestion of Water by Swimmers

. Exposure Scenario Cw 1 (mg/L) IgR 2 (L/hr) ET 3 (hr/day) BW 4 (kg) Oral Dose 5 (mg/kg/day) MOE 6 (LOC = 100)
S wimmer; adult 0.552 0.0 5 0.025 80 0.000008625 580,000
S wimmer; child (3 to <6 years old) 0.0 5 0.076 19 0.0001104 45,000

1 Cw = concentration in water is based on the application rate provided on the product label. An assumption of 4 feet depth (and uniform distribution) was used to estimate the concentration in water

. 2 IgR = ingestion rate of water ; based on the Risk Assessment Guidance for Superfund (RAGS) Part A ( http://www.epa.gov/oswer/riskassessment/ragsa/ ) which references a value from the Superfund Exposure Assessment Manual (USEPA, 1988). The recommended point estimate for use in post

- application incidental ingestion exposure assessments is 0.05 L/hr of swimming for adults and children 3 to < 6 years old.

3 ET =exposure time; based on 2011 E xposure F actors H andbook (Table 16

- 20)

. 4 BW = body weight; based on the Residential Pesticide Exposure Assessment SOP ( February

- 2012).

5 Oral dose = (Cw x IgR x ET) ÷ BW

6 MOE = NOAEL ( 5 mg/kg/day; adult and child) ÷ dose (mg/kg/day)



### 5.3 Residential Risk Estimates for Use in Aggregate As sessments

Table s 5 .3 .1 and 5.3.2 reflects the residential risk estimates that are recommended for use in the aggregate assessment for triclopyr.

MOE Approach (Table 5. 3.1)

• The recommended residential exposure for use in the short

- term aggregate assessment for children 1 to <2 years old reflects hand

- to

- mouth incidental oral exposure due to applications to turf.

Aggregate Risk Index ( ARI ) Approach (Table 5 .3.2)

• The recommended residential exposure s for use in the short

- term aggregate assessment for adults reflects handler inhalation exposure s from spot a pplications to turf via sprinkler can

.

• The recommended residential exposure for use in the short

- term aggregate assessment for children 3 to <6 years old reflects combined inhalation and ingestion of water by swimmers.

### Page 13 of 17 Table 5 .3. 1. Recommendations for the Residential Exposures for the Triclopyr Aggregate Assessment Using Total MOE Approach

. 1

Lifestage Residential Handler Residential Post

- application Dose (mg/kg/day) 2 MOE 3 Dose (mg/kg/day) 4 MOE 5

Dermal Inhalation Total Dermal Inhalation Total Dermal Inhalation Oral Total Dermal Inhalation Oral Total
Child (1 to <2

years old)

– ST Hand

- to

Mouth Exposure Due

to Turf Use N/A

- - 0.0228

- - - 220 220

1. Bolded risk estimates should contribute to the residential exposure portion of the aggregate assessment. 2. Residential Handler Dose = the highest handler doses for each applicable lifestage of all scenarios assessed

. Not applicable. 3. Residential Handler MOE = the MOEs associated with the high est doses identified

. Not applicable. 4. Residential Post

- application Dose = the highest post

- application dose for each applicable lifestage of all scenarios assessed (see Tables 5.0.3 through 5.0.5 ). Total = incidental o ral. 5. Residential Post

- application MOE = the MOEs associated with the highest doses identified (see Tables 5.0..3 through 5.0.5 ). Total MOE = 1/[(1/Inhalation MOE) + (1/Incidental oral MOE)], where applicable.

Table 5 .3. 2. Recommendations for the Resid ential Exposures for the Triclopyr Aggregate Assessment Using ARI Approach

. 1

Lifestage Residential Handler Residential Post

- application

Dermal MOE Dermal ARI Inhalation MOE 2 Inhalation ARI 2 Dermal MOE Dermal

ARI Inhalation MOE 2 Inhalation ARI 2 Oral MOE 3 Oral ARI 3 Total ARI 4

Adult

– M/ L/A Liquids to Turf with Sprinkler Can - - 1,900 1.9 N/A

Child (3 to <6 years old)

– Swimmer Exposure Due to Aquatic Use N/A

- - 520,000 520 45,000 450 240

1. B olded risk estimates should contribute to the residential exposure portion of the aggregate assessment. 2. MOE inhalation residential exposure = [(short

- term inhalation NOAEL)/(high end inhalation residential exposure)]. ARI inhalation = [(MOE inhalation residential exposure)/ (MOE target)]. Short

- term inhalation N OAEL = 5 mg/kg/day; high

- end inhalation residential handler exposure for adults = 0.00 26 mg/kg/day; high

- end inhalation residential post

- application exposure for children 3 to <6 years old = 0.00000955 mg/kg/day (swimmer). MOE target = 1000. 3. MOE oral resi dential exposure = [(short

- term oral NOAEL)/(high

- end incidental oral residential exposure)]. ARI oral residential exposure = [(MOE oral residential exposure)/(MOE target)]. Short

- term oral NOAEL = 5 mg/kg/day; high

- end incidental oral residential exposu re for children 3 to <6 years old (swimmer) = 0.00001104 mg/kg/day. MOE target = 100. 4. Total ARI = 1/[(1/ARI oral) + (1/ARI inhalation)].

### Page 14 of 17 5.4 Spray Drift

Spray drift is a potential source of exposure to those nearby pesticide applications. This is particularly the case with aerial application, but, to a lesser extent, spray drift can also be a potential source of exposure from the ground application methods (e.g., groundboom and airblast) employed for triclopyr. The agency ha s been working with the Spray Drift Task Force (a task force composed of various registrants which was developed as a result of a Data Call

- In issued by EPA), EPA Regional Offices and State Lead Agencies for pesticide regulation and other parties to develo p the best spray drift management practices (see the agency’s Spray Drift website for more information). 2 

### The agency has also developed a policy on how to appropriately consider spray drift as a potential source of exposure in risk assessments for pestic ides. The potential for spray drift will be quantitatively evaluated for each pesticide during the Registration Review process which ensures that all uses for that pesticide will be considered concurrently. The approach is outlined in the revised (2012) Standard Operating Procedures For Residential Risk Assessment (SOPs)

- Residential Exposure Assessment Standard Operating Procedures Addenda 1: Consideration of Spray Drift. This document outlines the quantification of indirect non

occupational exposure t o drift.

5.5 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 i ssues related to volatilization of pesticides from its Federal Insecticide, Fungicide, and Rodenticide Act Scientific Advisory Panel (SAP) in December 2009, and received the SAP’s final report on March 2, 2010 (http://www.epa.gov/scipoly/SAP/meetings/2009/ 120109meeting.html). The agency has evaluated the SAP report and has developed a Volatilization Screening Tool and a subsequent Volatilization Screening Analysis (http://www.regulations.gov/#!docketDetail;D=EPA

- HQ

- OPP

- 2014

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

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

6 .0 Occupational Exposure and Risk Estimates

The proposed action to remov e a grazing restriction for dairy cattle is not expected to result in occupational exposures; and the proposed registration of the choline salt is covered by the previous actions. As a result, no new occupational assessments have been conducted for these actions. However, occupational handler inhalation exposure and risk estimates were updated to reflect all of the currently registered uses of triclopyr for the July 2014 HASPOC meeting in order to assess the inhalation waiver request submitted by the tric lopyr registrants.

For mixers/loaders of the liquid formulation for aerial application by helicopter to forestry, the inhalation MOE is 41 . The current label requires baseline PPE (single layer clothing with gloves). With the addition of a PF5 or PF10 respirator to the label, MOEs for this scenario would increase

to 200 and 410 , respectively. These estimates are considered conservative given aerial applications are only made by helicopter and the high acreage default of 7,500 acres would be an

overest imate of the acreage that would be treated. Previously, data was obtained from the U.S.

2 Available: http://www.epa.gov/opp00001/factsheets/spraydrift.htm

### Page 15 of 17 Army Corps of Engineers, University of South Florida, and the South Florida Water Management District that indicated typical acreage treated with triclopyr by helicopt er was 100 acres (J.T. Swackhammer; 22

- JUL

- 2002; D269448). This estimate was not used for calculating MOEs for this evaluation because it is based on informal discussions from over a decade ago and commercial users were not included the estimate. More cu rrent, all

- inclusive data regarding the typical acreage that is treated with triclopyr using aerial applications by helicopter would be needed to refine this exposure scenario.

A summary of the occupational handler inhalation risk estimates from these use s of triclopyr are presented in Table 6.1.

### Page 16 of 17 Table 6.1. Triclopyr: Summary of Occupational Handler Inhalation Risks for Currently Registered Uses.

Activity Application Equipment Crop/Target Inhalation Unit Exposure (μg/lb ai) 1 App Rate 2 Acres 3 Dose 4 ST and IT Inhalation MOE (Baseline) 5 Mitigation Level
Mixer/Loader Groundboom app. of liquid formulation R ange and pasture, forests and non

- crop areas, including manufacturing and storage sites, rights

- of

- way such as electrical power lines, communication lines, pipelines, roadsides, railroads, fence rows, non

- irrigation ditch banks, and around farm buildings; and applications to grazed areas, and establishment and maintenance of wildlife openings, and in Christmas tree plantations and aquatic sites. 0.219 (baseline)
0.0438 (PF 5) 0.0219 (PF10) 9 lb ae/A 80 0.00198 2,500

Aerial /Helicopter app. of liquid formulation 6 lb ae/A 7,500 0.123 41

0.0246 200 (PF5)

0.0123 410 (PF10)

Groundboom app. of liquid formulation Rice 0.219 (baseline) 0.375 lb ae/A 200 0.000205 24,000

Aerial app. of liquid formulation 1,200 0.00123 4,100

Applicator
Applicator, Aeria l /Helicopter R ange and pasture, forests and non

- crop areas, including manufacturing and storage sites, rights

- of

- way such as electrical power lines, communication lines, pipelines, roadsides, railroads, fence rows, non

- irrigation ditch banks, and around farm buildings; and applications to grazed areas, and establishment and maintenance of wildlife openings, and in Christmas tree plantations and aquatic sites. 0.0049 (EC) 6 lb ae/A 7,500 0.00414 1,8 00 (EC)

Applicator, Open Cab Groundboom 0.34 (baseline) 9 lb ae/A 200 0.00306 1,600

Applicator, Aeria l
Rice 0.0049 (EC)
0.375 lb ae/A 1,200 0.0000276 180,000 (EC )

Applicator, Open Cab Groundboom 0.34 (baseline) 200 0.0000404 16,000

Mixer/Loader/Applicator

M/L/A Backpack Range and pastures and in non

- crop areas including industrial manufacturing and storage sites, rights

- of

- way such as electrical power lines, communications lines, pipelines, roadsides, railroads, fence rows, non

irrigation ditch banks and around farm buildings. Use on these sites may include application to grazed areas, as well as establishment and maintenance of wildlife openings. 2.58 8 lb ae/A or 0.75 lb ae/gal 40 gallons 0.000968 5,200

### Page 17 of 17 Table 6.1. Triclopyr: Summary of Occupational Handler Inhalation Risks for Currently Registered Uses.

Activity Application Equipment Crop/Target Inhalation Unit Exposure (μg/lb ai) 1 App Rate 2 Acres 3 Dose 4 ST and IT Inhalation MOE (Baseline) 5 Mitigation Level M/L/A spray boom, handgun, or other suitable equipment mounted on a boat or vehicle, helicopter. Aquatic Sites: For control of immersed, submersed and floating aquatic plants in aquatic sites such as ponds, lakes, reservoirs, non

- irrigation canals and ditches which have little or no continuous outflow, marshes and wetlands, including broadleaf and woody vegetation on banks and shores within or adjacent to these a nd other aquatic sites. 3.9 0.08436 lb

a e /gal 1,000 gallons 0.00411 1,200

M/L/A Handheld sprayer C ool season turfgrass, and on non

- crop areas including industrial sites, rights

of

- way (such as roadsides, electric utility and communication transmission lines, pipelines and railroads), non

- irrigation ditch banks, natural areas (such as wildlife management areas, wildlife openings, wildlife habitats, recreation areas, campgrounds, trailheads and trails) and grazed areas in and around these sites 30 0.23 lb a e /gal 40 gallons 0.00345 1,400

Flagger

Aerial spray app. Rice

0.35 (baseline) 0.375 lb ae/A

350 0.000574 8,700

R ange and pasture, forests and non

- crop areas, including manufacturing and storage sites, rights

- of

- way such as electrical power lines, communication lines, pipelines, roadsides, railroads, fence rows, non

- irrigation ditch banks, and around farm buildings; and applications to grazed areas, and establishment and maintenance of wildlife openings, and in Christmas tree plantations and aquatic sites. 9 lb ae/A 0.0138 360

1. Based on the “Occupational Pesticide Handler Unit Exposure Surrogate Reference Table”; Level of mitigation: Baseline, PPE (gloves), Eng. Controls. 2. Based on proposed labels. 3. Exposure Science Advisory Council Policy #9.1. 4. Inhalation Dose = Inhalation Unit Exposure (μg/lb ) × Conversion Factor (0.001 mg/μg) × Application Rate (lb a e /acre) × Area Treated (A/day) x IAF (100 %) ÷ BW (80 kg). 5. Inhalation MOE = Inhalation NOAEL (5 mg/kg/day) ÷ Inhalation Dose (mg/kg/day).