### 2 

# REGISTRATION REVIEW

PROBLEM FORMULATION

______________________________________________________________________________



# Triallate

CAS Number 2303

- 17

- 5

US EPA PC CODE 078802

Prepared by:

He Zhong , Ph.D., B iologist Faruque Khan , Ph.D., Senior Fate Scientist

Edom S e ifu, Intern

Environmental Risk Branch 1

Reviewed by: Meghan Radtke, Ph.D., Acting RAPL Steve Wente, Ph.D., Biologist

Environmental Risk Branch 1 U.S. Environmental Protection Agency

Office of Pes ticide Programs

Environmental Fate and Effects Division

Environmental Risk Branch I 1200 Pennsylvania Ave., NW

Mail Code 7507P Washington, DC 20460

### 3



## 1 Executive Summary

The Environmental Fate and Effects Division (EFED) has completed the preliminary probl em formulation for the ecological risk, environmental fate, endangered species, and drinking water

assessments to be conducted as part of the Registration R eview of triallate . The problem formulation describes the methods planned to be used during the com pletion of drinking water and ecological risk assessments in support of R egistration R eview and provides an overview of the environmental fate, ecological effects, and potential risks associated with the use of triallate as well as uncertainties unique to the risk assessment of triallate . This document also identifies

the label deficiencies and additional studies that are required for an ecological risk assessment.

Pesticide Label Clarification Needed:

For All Label s

 The m aximum number of applications per year

 The maximum annual application rate (lb a.i. per acre)

 The m inimum application intervals

For Granular Labels:

 The average size and a.i. of a single granul e

Major Data N eeds

 Guideline 835.4400

– Anaerobic Aquatic Metabolism for triallate

 Gui deline 850.6100

– Environmental Chemistry and Independent La boratory Validation

methods for triallate and its degradate 2,3,3

- trichloro

- 2

- propenesulfonic acid (TCPSA)

, (water and soil).

 Guidelines 850.1035,

– A cute toxicity for estuarine/marine invertebrat es ( mysid shrimp )

for triallate

 Guidelines 850.1025, 850.1045 and 850.1055

– Acute toxicity for estuarine/marine

mollusk ( select one

- oyster, penaeid or bivalve ) for triallate

 Guideline 850.1075

– Saltwater fish a cute toxicity for triallate (recommend th e same saltwater fish species for acute and chronic studies)

 Guideline 850.1350

– Saltwater invertebrate life cycle for triallate

 Guideline 850.1400

– Saltwater fish early

- life stage for triallate (recommend the same saltwater fish species for acute and chronic studies)

 Non

- g uideline

– Whole sediment invertebrate chronic toxicity ( Chironomus dilutus

, freshwater amphipod Hyalella azteca , and estuarine/marine amphipod Leptocheirus plumulosus ) for triallate

 Guideline 850.4550

– Cyanobacteria toxicity for t riallate

 Guideline 850.2100

– Avian acute oral toxicity ( passerine ) for triallate

 Guideline 850.2300

– Avian reproduction (waterfowl) for triallate

 Non

- guideline honeybee adult chronic oral toxicity for triallate

 N on

- guideline honey bee larval acute and c hronic oral toxicity for triallate

Justifications for these data needs as well as assumptions that will be made in the absence of the data are provided in Section 11

.

### 4



## 2 Introduction

Triallate was first registered as a pesticide in the U.S. i n 1961 (US EPA 2001). Triallate is a thiocarbamate pre

- emergence selective herbicide that inhibits the synthesis of lipids and prohibits shoot growth of emerging seedlings.



## 3 Use Characterization

Triallate is a thiocarbamate pre

- emergence selective grass herbicide that is used to control wild oats, black grass, and annual meadow grass

. The chemical profile produced by the B iological

and E conomic A nalysis D ivision (BEAD), located in the docket, lists the use patterns of maximum exposures for the current uses of triallat e. The usage data show a declining trend in
recent years from an average of 2 million lbs/yr (1998

- 2002) to 156,000 lbs/yr (2008

- 2013) and

t he registered agricultural use sites of triallate include: B ermuda grass (grown for seed or hay), dry beans and pea s, green peas, lentils, barley, spring wheat, triticale, and sugar beets (USEPA

2014 a ). The highest average annual rate (a.i.) is 1.109 lbs a.i./acre on barley in 2008

- 2012 (Table 3

- 1 )

.

Table 3

- 1. Triallate Use on Top Crops, 2008

– 2012 Crop Average A nnual

Applied (lbs a.i.) Average Annual

Total Acres Treated* Average Annual Rate (lbs a.i. / acres) Barley 54,533 49,177 1.109 Spring Wheat 50,567 49,441 1.023 Dry Bean/Pea 33,139 34,397 0.963

Winter Wheat 17,968 17,889 1.000

*Total Acres Treated sums all acres treated for a crop, including those acres that received multiple treatments



### Triallate is available as an emulsifiable concentrate (Far

- GO ® 

### Herbicide (EPA Reg. No. 100163

- 286)) , foliar spray, water

- dispersible granule (WDG), and granular formula tion s (Avadex

MinTill Herbicide (EPA Reg. No. 100163

- 287) and (BUCKLE, EPA Reg. No. 100163

- 289)

. The BUCKLE granular herbicide is a mixture of triallate and trifluralin, must only be applied by ground methods. Depending on the crop that is treated, the h erbicide is applied either before or after planting. According to the label, triallate can be applied as a surface broadcast (no

- till) or incorporated in the soil with a maximum single application rate of 1 to 1.5 lbs a.i. per acre.

Th ere are two major issues on the labels: 1). t he average granular size and a.i. are not specifi ed on the granular labels; 2). t he minimum application intervals, the maximum annual application rate (lb a.i. per acre) and numbers are not specified for all registered labels

. Without the maximum annual application numbers, EFED will use application scenarios that result in maximum exposure scenarios

, such as: multiple crop seasons in a year, for a given use for the risk assessment (see Appendix A for summary of labels).



## 4 Conclu sions from Previous Risk Assessments

4.1 Ecological Risk Assessments

### 5

The most recent triallate assessments includ e a RED (USEPA 2001) and a Section 3 new use registration request for use on Bermuda grass seed treatment (USEPA 2009 a , DPs 351896,

352259 and 35 8774). The se two assessment s indicated that the use of triallate may cause direct

and indirect effects to listed aquatic invertebrates

, land

- phase amphibians, reptiles and small mammals; listed and non

- listed terrestrial and semi aquatic plants; and non

- l isted aquatic invertebrates in unprotected shallow water habitats, such as potholes, bogs, or wetlands.

The following data gaps were identified in the 2009 assessment:

 Guideline s 850.1025, 850.1035, 850.1045 and 850.1055

– Estuarine/marine acute

toxi city data for invertebrates, and mollusks.

 Guideline 850.1075

– Estuarine/marine fish acute toxicity data

 Guideline 850.1350

– Estuarine/marine invertebrate life cycle data

 Guidelines 850.1400 and 850.1500

– Estuarine/marine fish chronic toxicity data

4.2 D rinking Water Exposure Assessments

The most recent drinking water exposure assessment for triallate was conducted in 2008 to establish tolerances for triallate and its degradate 2,3,3

- trichloro

- 2

- propenesulfonic acid (TCPSA) on Bermuda grass ( USEPA 2009 b

, D35 8774 ) . Recommended Estimated Drinking Water Concentrations (EDWCs) were modeled for the total toxic residue s (TTR) of parent
triallate and its degradate 2,3,3

- trichloro

- 2

- propenesulfonic acid (TCPSA)

. Recommended

surface water EDWCs for TTR of triall ate from currently labeled uses are 9.45 μg/L (1

- in

- 10

- year peak) for acute, and 1.26 μg/L (36

- year mean) for chronic ; the groundwater EDWC is 0.02 μg/ L for both acute and chronic (U SEPA, 2001)

.

4.3 Clean Water Act Programs

Triallate is not identified as a cause of impairment for any water bodies listed as impaired under section 303(d) of the Clean Water Act. No Total Maximum Daily Load (TMDL) criteria have been developed for triallate . Aquatic benchmarks have been established for triallate and are

availab le at http://www.epa.gov/oppefed1/ecorisk_ders/aquatic_life_benchmark.htm . Any data

submitted or ot herwise located as part of the Registration R eview process may be used t o update aquatic life benchmarks

, if applicable.



## 5 Environmental Fate and Transport

A summary of physical, chemical and environmental fate properties of triallate ( S

- (2,3,3

- trichloro

- 2

- propenyl)bis(1

- methylethyl) carbamothioate ) are presented in Table 5

- 1

. The physicochemical properties indicate that triallate has a low water solubility (4 mg/L at 25°C). The vapor pressure of 1.20 x 10

- 4 

### mm Hg indicates that triallate is a semi

- volatile chemical and Henry's law constant of 1.20 × 10

- 5 

### atm

- m3/mol sugge sts volatilization is expected to be a major route of dissipation from moist soil and water. Triallate volatilized with a flux rate of 3.6 x 10

- 3


### μg/cm 2 

### /hr from sand treated at a rate of 1.5 lb. a.i./A in a laboratory study

. O pen literature data

also indi cate that triallate volatilization is a major route of dissipation under actual use

### 6

conditions. In a USGS review, triallate volatilization accounted for 15% and 74% of applied

materials for incorporated and unincorporated triallate respectively (Majewski and Capel, 1995). In another study (Smith et al., 1997), 21 % of applied triallate volatilized over a 24

- day period after application of granular triallate.

Triallate has a potential to bioaccumulate (log K ow 

### = 4.55). The potential to bioaccumulate was

su pported by the results of a fish bioconcentration factor (BCF) study (BCF’s of 700 in edible tissue, 2700 in visera and 1600 in whole fish). However, the depuration of triallate from fish is relatively quick (> 90% within 14 days following the end of the exposure); therefore, bioconcentration will only occur in situations with continued or repeated exposure of triallate in

surface water.

Triallate is stable to abiotic degradation processes including hydrolysis, aqueous photolysis, and photolysis on soil. The major mode of triallate degradation is aerobic soil metabolism (DT 50s 

### of

18

- 60 days), which occurs with significant mineralization. In addition, DT 50s 

### of 45 days and 49 days were observed for the encapsulated and unencapsulated triallate formulatio ns
, respectively. Triallate metabolizes much more slowly and is considered stable under anaerobic conditions. Under aerobic aquatic conditions, DT 50 

### values ranged from 64 to 74 days in a sediment

- water
system. Volatilization of the parent may have contr ibuted to the overall dissipation during the laboratory studies. No major degradate was identified except CO 2



### . Several unidentified minor

metabolites and < 5% of 2,3,3

- trichloroprop

- 2

- ene sulfonic acid (TCPSA) were detected in the laboratory studies ( Appen dix B )

.

The batch equilibrium data for adsorption coefficients (K ads 

### ) ranged from 5.3 ml/g to 35 ml/g.

Calculated K oc 

### values for triallate ranged from 1305 ml/g to 2730 ml/g , which suggests triallate is slightly mobile according to the pesticide mobi lity classification of the Food and Agriculture Organization (FAO 2000)

. Soil column leaching studies appear to confirm triallate's lack of mobility in soil. In an aged column leaching study, 7% of the applied radioactivity was found in

the leachate. In a supplemental study comparing the leaching behavior of encapsulated and unencapsulated formulations, the concentration of radioactivity in the leachate was 4.7 % and 17.5 % of the applied C 14



### - activity for encapsulated and unencapsulated triallate, respect ively.
However, t he leached material was mainly the triallate metabolite 2,3,3

- trichloropro p

- 2

- ene sulfonic acid (TCPSA) , which is a concern for the Health Effects Division’s tolerance expression but it is not a concern for ecological risk assessment. Si nce TCPSA is a minor degradate and unstable in the environment (EPISUITE 4.1 predicted DT50
s 

### of 38 hours in water and 62 hours in soil) as well as several fold less toxic to aquatic organisms, it will be not included in aquatic
exposure assessment.

Field dissipation studies with a granular formulation suggest that triallate dissipated with DT 50s 

### of 20

- 190 days in six U.S. locations (ID 60 days, SD 20 days, MT 30 days, ND 50 days, KS 85 days, and WA 190 days). In five of the six locations, the half

- life wa s 85 days or less. Factors contributing to the rate of dissipation include volatilization, soil binding, and how favorable conditions are for microbial growth.

Table 5

- 1. Physical, Chemical and Environmental Fate Properties of Triallate and its Major Env ironmental Degradate (TCPSA)

### 7

Property Value Source & Study

Classification

PARENT

Common name Triallate US EPA, 2001

CAS Registry No. 2303

- 17

- 5

PC Code 078802

Chemical name (CAS) S

- (2,3,3

- trichloro

- 2

- propenyl)bis(1

- methylethyl)

carbamothioate

Cl ass thiocarbamate

SMILES notation CC(C)N(C(C)C)C(=O)SCC(CL)=C(CL)CL EPI Suite, v3.12

SMILES

IUPAC name S

- 2,3,3

- tricloroallyl di

- isopropylthiocarbamate IUPAC

Synonyms None Identified.

Structure EPI Suite, v3.12

Molecular formula C 10 H 16 C 13 NOS US E PA, 2001

Physical and Chemical Properties

Molecular weight 304.66 USEPA, 2001

Physical state Amber or white crystalline solid

Vapor pressure 1.2 x 10

- 4 mm Hg

Henry’s Law constant 1.2 x 10

- 5 atm x m 3 /mol

Specific gravity/density 1.38g/cm 3 @ 20 o C MRID 44731803 Acceptable

Solubility in water 4 mg/L @ 25 o C USEPA, 2001

log K
ow 4.55

Laboratory Volatility 3.6 E

- 03 (μg/cm 2

- hr) MRID 42651101 Acceptable

Laboratory accumulation in fish bioaccumulation factor (BCF) 670x in edible tissues

2700x non

- edible (viscera) tissues 1600x for whole body MRID 41497601 Supplemental

### 8

Property Value Source & Study

Classification

Depuration half

- life 14 days

Environme ntal Fate Properties

Hydrolysis half

- life Stable at pH 4, 6, 7, and 8, MRID 00144567 Acceptable

Photolysis half

- life in water Stable MRID 00144567

MRID 41541301 Acceptable

Photolysis half

- life in soil Stable MRID 41892301 Acceptable

Aerobic soil metabolism half

- life 18 days (Silt loam) @ 30°C No major degradates detected except CO 2 MRID 00144567

Acceptable

Encapsulated Formulated Product 45 days (Silt loam) @ 30°C Unencapsulated Formulated Product 49 days (Silt loam) @ 30° C

No major degradates Minor degradates

- TCPSA (3.4% @ day 31 ) MRID 44611302

Supplemental

37 days (clay loam) @ 20°C 57 days (sandy loam 1) @ 20°C 60 days (sandy loam 2) @ 20°C 58 days (silty clay loam) @ 20°C 98 days (sandy loam 1) @ 10°C

Major Degra dates No major degradates detected except CO 2

.

Minor Degradates 3.74% TCPSA @ Day 120 5 unidentified degradates @ Day 120 MRID 44715601 Supplemental

Anaerobic soil metabolism half

- life Stable MRID 00144567

MRID 44611302 Supplemental

Aerobic aquatic m etabolism half

- life for total system 74 days (Total system

- Sandy loam) @ 20°C 64 days (Total system

- Clay loam) @ 20°C

14 days (Sterile deionized water) @ 20°C 5 days (Sterile deionized water) @ 26°C

4

- 25 days (water s/naturally suspended solids) @

20°C t o 26°C MRID 44715501 Supplemental

MRID 44715502 Supplemental

### 9

Property Value Source & Study

Classification

TCPSA and other more polar, unidentified, triallate degradates (< 4%) were reported to be

detected in river water and sediment.

Soil adsorption coefficient

K
oc (L/kg) Adsorption

K ads 19 (silt loam) 35 (silty clay loam) 24 (sandy loam)

5

. 3 (sandy loam)

K
oc (ml/g) (calculated) 2730 (silt loam) 1775 (silty clay loam) 1724 (sandy loam) 1305 (sandy loam) MRID 00144567 (Acceptable)

Terrestrial field dissipation half

- life Six U.S. Locations

6 0 days (ID) 20 days (SD) 30 days (MT) 50 days (ND) 85 days (KS) 190 days (WA) MRID 00145426 (Acceptable)



## 6 Receptors

Summaries of the submitted toxicity data used to characterize the toxicity of triallate to terrestrial and aquatic organisms are pr ovided in Table 6

- 1

.

Triallate is practically non

- toxic to water

- fowl and upland game birds on acute oral and sub

dietary bas i s ; practically non

- toxic to adult honey bees on an acute contact and oral bas i s; slightly toxic to mammals on an acute oral bas is; moderate ly toxic to earthworm; and very highly

toxic to freshwater fish and freshwater i nvertebrates on an acute basis. Triallate was r eported to

form CO 2 

### as a sole major degradate. A minor degradate, TCPSA, is of concern for drinking
water exposure. The eco

- toxicity data for TCPSA were not submitted

. The estimated toxicit y by

the ECOSAR shows that the TCPSA is much less toxic than the parent triallate ( Appendix C ). Therefore, TCPSA is not considered as a stressor of the concern in this ecological r isk

assessment.

### 10

Table 6

- 1. Summary of Endpoints from Toxicity Studies with Triallate

Study Type Test Substance (% a.i.) Species Toxicity Endpoints and Acute Toxicity Classification (If Applicable) Source & Study

Classification

Avian acute oral:

5

- week observation Triallate

Technical (95.1) Bobwhite quail

( Colinus virginianus ) LD 50 = 2,251 mg a.i./kg

- bw (95% C.I.:1,792

- 2,828) LOAEL = 398 mg a.i./kg

- bw (the lowest dose)

NOAEL < 398 mg a.i./kg

- bw (A dose related decline in body weights were obser ved in all test

concentrations . Signs of general toxicity include lethargy, reduced reaction to external stimuli and depression, loss of

co o rdination head tremors, strong dorsal flexion of the head and convulsions)

Practically non

- toxic MRID 00083035 Acceptable

NA Passerine species No data NA

Avian sub

- acute dietary: 8

- day

observation Triallate

Technical (96.3) Bobwhite quail

( Colinus virginianus ) LD 50 > 5,620 mg a.i./kg

- diet

L OAEL = 5,620 mg a.i./kg

- diet (One bird displays head curling and somers aulting from Day 1 to Day 12. Weight reduction is observed at the 5620 ppm treatment group at Day 5)

Practically non

- toxic MRID 40370609 Acceptable

Avian sub

- acute dietary: 8

- day

observation Triallate

Technical (98.26) Mallard duck

( Anas platyrhynchos ) LC 50 > 5,620 mg a.i./kg

- diet

L OAEC = 1,780 mg a.i./kg

- diet (Reviewer reported a body weight reduction in 1,780, 3,160 and 5,620 ppm concentrations and a reductions in feed consumption at the 3,160 and 5,620 ppm concentrations).

Practically non

- toxic M RID 40730609 Acceptable

Avian reproduction:

22 weeks (chronic) Triallate

Technical (98.26) Bobwhite quail

( Colinus virginianus ) LOAEC = 500 mg a.i./kg

- diet NOAEC = 200 mg a.i./kg

- diet (Most sensitive endpoints: Adult male bodyweight) MRID 44700701

Acc eptable

Mammalian acute oral; 14

- day

observation Triallate

Technical (90.16 %) 1 Rat

( Rattus norvegicus ) LD 50 > 1,100 mg a.i./kg

- bw (95% C.I.:900

– 1,300)

NOAEL: not determined MRID 00109746 Acceptable

### 11

Study Type Test Substance (% a.i.) Species Toxicity Endpoints and Acute Toxicity Classification (If Applicable) Source & Study

Classification

Mammalian acute oral, 15

- day

observation Triallate

Technical ( 96.84 ) Rat

( Rattus norvegicus ) LD 50 = 3,382 mg a.i./kg

- bw (combined), (male = 3,612 and female = 3,445 mg a.i./kg

- bw)

NOAEL: not determined MRID 44660701 Acceptable

Mammalian 2

- generation reproduction (chronic) Triallate

Technical (94.5) Rat

( Rattus norvegicus ) Parental, systemic toxicity LOAEC = 30 mg a.i./kg

- bw/day NOAEC = 7.5 mg a.i./kg

- bw/day) (reduced pregnancy and shortened gestation) MRID 00144308

MRID 00132880 Acceptable

Earthworm Triallate

Technical (96.84) ( Eisenia foetida ) LC 50 = 548 mg a.i./Kg soil

L OAEL = 270 mg a.i./Kg soil (adverse effects on earthworm populations at LOAEL)

Moderately toxic MRID 44581701 Supplemental

Honey bee acute contact: single dose,

48

- hour observation Triallate

Technical (97.1) Adult honey bee

( Ap is mellifera ) LD 50 > 25 μg a.i./bee NOAEL = 25 μg a.i./bee

Practically non

- toxic MRID 42304301 Acceptable

Honey bee dietary

LC 50 Study, 48

- hour

observation Triallate

Technical (96) Adult honey bee

( Apis mellifera ) LC 50 > 1000 ppm or > 292 μg a.i./bee (1000 μg a.i./g x 0.292 g/day) NOAEC = 63 ppm or = 18.4 μg a.i./bee (63 μg a.i./g x 0.292 g/day) MRID 44700801 Acceptable

Honey bee chronic oral toxicity NA Adult honey bee ( Apis mellifera ) NA NA

Honey bee larval

acute an d chronic

oral toxicity NA Larval bee ( Apis mellifera ) NA NA

Terrestrial plant seedling emergence:

Tier II Triallate

Technical (97.67) Most sensitive dicot:

Cucumber EC 50 =0.5 lb a.i./A

EC 25 =0.18 lb a.i./A

LOAEC = 0.17 lb a.i./A

NOAEC = 0.056 lb a.i./ A

The most sensitive parameter: plant dry weight MRID 42471801 Acceptable

Most sensitive

monocots: Oat EC 50 =0.033 lb a.i./A

EC 25 =0.020 lb a.i./A

LOAEC = 0.019 lb a.i./A

NOAEC = 0.010 lb a.i./A

### 12

Study Type Test Substance (% a.i.) Species Toxicity Endpoints and Acute Toxicity Classification (If Applicable) Source & Study

Classification The most sensitive parameter: plant dry weight

Terres trial plant vegetative vigor: Tier II, 21 days Triallate

Technical (97.67) Most sensitive dicot:

Cucumber EC 50 = 0.18 lb a.i./A

EC 25 = 0.072 lb a.i./A

LOAEC > 0.17 lb a.i./A

NOAEC = 0.056 lb a.i./A

Most sensitive parameter: plant dry weight MRID 42471 701 Acceptable

Most sensitive monocot:

Oat EC 50 = 0.12 lb a.i./A

EC 25 = 0.033 lb a.i./A

LOAEC > 0.019 lb a.i./A

NOAEC = 0.010 lb a.i./A

Most sensitive parameter: plant dry weight

Freshwater fish acute: 96 hours,

flow

- through Triallate

Technical ( 92.7) Bluegill sunfish

( Lepomis macrochirus ) LC 50 = 1,330 μg a.i./L (95% C.I.:710

- 1,400) NOAEC < 270 μg a.i./L (NOAEC based on signs of toxicity including paralysis, dark pigmentation and letharg y , and los s of equilibrium)

Moderately toxic MRID 0008364 1 Acceptable

Triallate

Formulated

Product (46.5) Bluegill sunfish

( Lepomis macrochirus ) LC 50 = 2,400 μg a.i./L (95% C.I.:1,800

- 3,200)

NOAEC: N/A MRID 00076890 Acceptable

Triallate

Technical (96.95) Rainbow trout

( Oncorhynchus mykiss ) LC 50 = 1,200 μ g a.i./L (95% C.I.:960

- 1,500) NOAEC = 560 μg a.i./L (loss of equilibrium and surfacing)

Moderately toxic MRID 00029469 Acceptable

Triallate

Formulated

Product (46.5) Rainbow trout

( Oncorhynchus mykiss ) LC 50 = 1,500 μg a.i./L (95% C.I.:1,000

- 3,200)

N OAEC: N/A MRID 00076889 Acceptable

Freshwater fish early life stage: 88 days,

flow

- through (chronic) Triallate

Technical (96.84) Rainbow trout

( Oncorhynchus mykiss ) LOAEC = 78 μg a.i./L NOAEC = 38 μg a.i./L

Most sensitive endpoint: growth (31 day post

- h atch length, dry weight and wet weight). MRID 44660901 Acceptable

### 13

Study Type Test Substance (% a.i.) Species Toxicity Endpoints and Acute Toxicity Classification (If Applicable) Source & Study

Classification

Freshwater

invertebrate acute: 48 hours, flow

through Triallate

Technical (95.53) Water flea

(Daphnia magna) EC 50 = 91 μg a.i./L (95% C.I.:79

- 103) NOAEC = 43 μg a.i./L

Very highly toxic MRID 41895601 Acceptable

Triallate

Technical (96.95) Water flea

(Daphnia magna) LC 50 = 430 μg a.i./L (95% C.I.:380

- 490) NOAEC = 180 μg a.i./L

Highly toxic MRID 00029470 Acceptable

Freshwater

invertebrate life cycle: 21 days, flow

th rough (chronic) Triallate

Technical (97.2) Water flea

(Daphnia magna) EC 50 > 56 μg a.i./L LOAEC =28 μg a.i./L NOAEC = 14 μg a.i./L (EC 50 based on immobility; LOAEC and NOAEC based on total length). MRID 45775401 Acceptable

Benthic invertebrate NA NA No data NA Aquatic vascular plant: 7 days, static

renewal Triallate

Technical (97.2) Duckweed

(Lemna gibba) EC 50 (.) = 2400 μg a.i./L (95% C.I: 16

- 27) LOAEC = 2100 μg a.i./L NOAEC = 1100 μg a.i./L (NOAEC based on reduction in frond number) MRID 4 5653205 Acceptable

Aquatic non

vascular plant: 96 hours, static Triallate

Technical (97.2) Marine Diatom

( Skeletonema costatum ) EC 50 = 330 μg a.i./L (95% C.I :260

– 400) LOAEC = 180 μg a.i./L NOAEC = 73 μg a.i./L (Most sensitive endpoint: the area un der the growth curve) MRID 45653204 Acceptable

Triallate

Technical (97.2) Freshwater Diatom

( Navicula pelliculosa ) EC 50 = 1300 μg a.i./L (95% C.I :1,200

– 1,300) LOAEC = 1140 μg a.i./L NOAEC = 538 μg a.i./L (based on biomass) MRID 45653203 Acceptable

Triallate

Technical (97.2) Green alga

( Selenastrum capricornutum ) EC 50 = 21 μg a.i./L (95% C.I.: 0.018

- 0.023) LOAEC = 13 μg a.i./L NOAEC = 6.31 μg a.i./L (based on reduction in cell density) MRID 45653201 Acceptable

Triallate

Technical (96.4) Green a lga

( Selenastrum capricornutum ) EC 50 = 140 μg a.i./L (95% C.I.: 120

- 170) NOAEC = 32 μg a.i./L (Biomass, rather than cell density, was used to assess the response of the alga to the test material) MRID 44700901 Supplemental

C.I. = confidence interval; NA = not applicable;

1 The % a.i. is calculated by 1.1g a.i./kg / 1.22g/kg x 100 = 90.16 % a.i.

### 14

6.1 Ecological Incidents

The ecological incident information system (EIIS) is an OPP database for ecological incidents

that have been reported to the Agency. When available, EIIS includes date and location of an incident, type and magnitude of effects observed in various species, use(s) of pesticides known or suspected of contributing to the incident, and results of any chemical residue analysis or other analyses c onducted during the incident investigation. EIIS incidents are categorized according to the certainty that the incident resulted from pesticide exposure. The Avian Monitoring System (AIMS ) 1 

### is a database administered by the American Bird Conservancy that contains publicly available data on reported avian incidents involving pesticides. A r eview of the EIIS (version 2.1.1) on March 16, 2014 found four cases of crop damage incidents from 1993

– 2000 related to triallate application on wheat and spring whea t

, and with one case of possible accidental

carryover that may not be considered further (Table 6

- 1)

. A r eview of AIMS on May 16 , 2014 did not yield any reported ecological incidents associated with the use of triallate

.

Table 6

- 1

. Triallate Incidents Identified in the EIIS Database

Incident

Number Organism Description Legal Other

Chemicals

I nvolved Caused By

Triallate ?

I003629

- 006 Spring wheat Plant damage in all direct

treatment area Registered

use No P robable

I0 00360

- 013 Spring wheat 75 acres plan t damage Registered

use No Possible

I000360

- 003 Wheat Unspecified acreage plant damage Registered

use No Possible

I003629

- 011 Wheat Plant mortality in direct

treatment area Registered

use No P robable

I010927

- 020 Wheat 240 acres plant damage by accide ntal carryover Misuse No Possible



### A dditional incid ents are reported to the Agency’s Incident Data System 2 

### by p esticide registrants as aggregate counts of incidents occurring per product per quarter. Ecological incidents reported in aggregate reports inc lude those categorized as ‘minor fish a nd wildlife’, ‘minor plant’, ‘other

non

- target’ incidents ’, ‘drinking water’, ‘surface water’, ‘groundwater’ and ‘domestic animal’

. ‘Other non

- target’ incidents include reports of adverse effects to insects and other terrestrial

invertebrates. For triallate

, registrants have reported two groundwater contamination incidents in

2000 as of a review on May 16 , 2014

.

The total number of actual incidents associated with the use of triallate may be higher than what

is re ported to the Agency. Incidents may go unreported since effects may not be immediately apparent and/or readily attributed to the use of a chemical. Therefore, a lack of reported incidents should not be taken as an indicator of little or no ecological ris k. The reported incidents suggest possible adverse effects to the crop and contamination to ground water for triallate field application. Even though the specific cause for the incidents was not identified, the uncertainty and data gap exists for the reg istration review risk assessment.

____________________________________________ 1 http://www.abcbirds.org/abcprograms/policy/toxins/aims/ aims/login.cfm?CFID=180204405&CFTOKEN=48160013

2 https://w2032pcctr563.aa.ad.epa.gov:8500/IDS/index

### 15



## 7 Exposure Pathways of Concern

The environmental fate properties and use patterns of tri allate indicate that direct spray, spray drift, leaching to ground water

, and runoff represent potential transport mechanisms of triallate to aquatic and terrestrial organisms.

Drinking water and inhalation exposure pathways were screened using the SIP (Screening Imbibition Program) and STIR (Screening Tool for Inhalation Risk) screening methods and were found to be exposure pathways of low concern (no LOC exceedances are expected ; see Appendix D ). SIP and STIR are described in detail at: http://www.epa.gov/oppefed1/models/terrestrial/index.htm

.



## 8 Analysis Plan

8.1 Stressors of Concern

8.1.1 Ecological Risk Assessment

The stressor of concern for both aquatic and terrestrial organisms is parent triallate only. The degradate TCPSA is not a concern because it becomes a much less toxic acid after the loss of the carbamate moiety

, based on the ECOSAR estimation of the relative toxicity ( Appendix C ).

8.1.2 Drinking Water Exposure Assessment

An EFED drinking water assessment was conducted for Bermuda grass grown for seed to establish tolerances of triallate and its degradate TCPSA for human health risk assessment (USEPA 200 8; DP358774 ). Recommended Estimated Drinking Water Concentrations (E DWCs)

were modeled for TTR of triallate and its degradate TCPSA

. EFED will conduct a drinking water assessment to support future human health dietary risk based on a TTR assessment of triallate and TCPSA. The drinking water assessment will be performed b ased on EFED’s current guidance using appropriate surface and groundwater models. Descriptions of all executable versions of current models for drinking water exposure can be obtained from URL link. http://www.epa.gov/oppefed1/models/water/

8.2 Measures of Exposure

EFED will use standard available models to evaluate potential exposures of triallate to aquatic and terrestrial organisms as described at http://www.epa.gov/pesticides/science/models_db.htm

. The latest developed and approved model s , such as the surface water calculator (SWCC), will

also be used.

8.2.1 Available Monitoring Data

### 16

The Agency is aware of monitoring conducted by federal and state agencies such as U

. S

. G eological S urvey (USGS) National Water Quality Assessment (NAWQA) Data Warehouse and

Cal ifornia Environmental Data Excha nge Network (CEDEN) . T his route of exposure will be

considered in the assessment to the extent that data on triallate are available.

8.3 Measures of Effect

Toxi city data presented in Section 6 of this problem formulation will be used to calculate risk quotients. Any additional information submitted by the registrant or found in the open literature

p rior to conduct ing the risk assessment will also be considered. The open literature studies are identified using EPA’s ECOTOXicology database ( http://cfpub.epa.gov/ecotox/ ), which employs

a literature search en gine for locating chemical toxicity data for aquatic life, terrestrial plants, and wildlife. The evaluation of both sources of data can also provide insight into the direct and indirect effects of pesticides on biotic communities from the loss of species that are sensitive to the chemicals and from changes in structure and functional characteristics of the affected

communities.



## 9 Endangered Species Assessments

Consistent with the Agency’s responsibility under the Endangered Species Act (ESA), the Agency wi ll evaluate risks to federally listed ( threatened and/or endangered ) species from registered uses of pesticides in registration review. The process for evaluating potential risks to listed species is further described at http://www.epa.gov/oppfead1/endanger/litstatus/riskasses.htm

.



## 10 Endocrine Disruptors Screening Program

Triallate was not included in the first group of 67 chemicals nor the second group of 109

chemicals that will o r have been issued an order to conduct Tier 1 EDSP testing. For additional

information on the EDSP program, visit http://www.epa.gov/endo/

.



## 11 Preliminary Identification of Data Gaps

11.1 Environmental Fate

Table 11

- 1 identifies environmental fate studies that offer data for each guideline requirement and whether or not further data are needed to support a risk assessment. There are no

environmental fate studies available for triallate degradate TCPSA which w ill be inc luded in the drinking water assessment

. If any empirical environmental fate data related to TCPSA are available, agency encourages the registrant to provide them during the comment period. Additional environmental fate and physicochemical properties of TC SPA can reduce the uncertainties for drinking water assessments. In the absence of physicochemical and environmental fate data of TCPSA, the Estimation Programs InterfaceSuiteTM (EPI Suite TM ) will

be used to estimat e fate parameters. EPI SuiteTM is a Windows ®



### - based suite of physical/chemical

### 17

property and environmental fate estimation programs developed by the EPA’s Office of Pollution Prevention Toxics and Syracuse Research Corporation (SRC).

Table 1 1

- 1. Submitted Environmental Fate Data for Triallate

OCSPP

Guideline Data

Requirement Submitted

Studies (MRID) Study

Classification Are data

needed to

conduct risk

assessment? Justification and Assumptions

EPA will Make in Absence of

Data

835.2120 Hydrolysis 00144567 Acceptable No

---

835.2240 Aqueous

photolysis 41541301 Acceptable No

---

835.2410 Soil photolysis Registration Summary (00086400) Acceptable No

---

835.4100 Aerobic soil

metabolism 00144567

44611302

44715601 Acceptable

Supplemental Supplemental No

---

835.4200 Anaerobi c soil

metabolism Add MRID

for the one study you do

have Supplemental No OCSPP guidance recommends that these tests be performed with

radio labelled TGAI/PAIRA for

four soils. One an aerobic soil metabolism study has been

submitted with formulated products and is classified as supplemental for risk assessment. Additional data are required

under 40 CFR Part 158 for

terrestrial outdoor uses.

Additional data are considered to have a low potential to add value to exposure assessments for the ecological risk and drinking water in presence of anaerobic aquatic metabolism ( 835.4200)

. 835.4300 Aerobic aquatic

metabolism 44715501

44715502 Supplemental No

---

835.4400 Anaerobic

aquatic

metabolism No Data

--- Yes Data are required under 40 CFR

Part 158. OCSPP guidanc e recommends that these tests be performed with two sediments

. The assumption of compound stability will be made in the absence of acceptable data.

835.1230

835.1240 Adsorption/

desorption and leaching 00144567 Acceptable No

---

835.1410 Volatility

–

lab oratory 42651101

46186001 Acceptable No

---

### 18

OCSPP

Guideline Data

Requirement Submitted

Studies (MRID) Study

Classification Are data

needed to

conduct risk

assessment? Justification and Assumptions

EPA will Make in Absence of

Data

835.6100 Terrestrial field

dissipation 00145426 Acceptable No

---

850

- 6100 Analytical

method in soil 40117901 Invalid Yes Environmental chemistry method (ECM) and independent laboratory validations (ILV) fo r soil and water are required for triallate and its degradate,

TCPSA Analytical

method in water No Data

-- Yes

165

- 4 (850.1730) Fish

bioconcentration 41497601 Supplemental No

--



### 11.2 Ecological Effects

For triallate, there are no data available for acut e oral toxicity to a passerine species, acute dietary (oral) toxicity to larval honey bees, chronic oral toxicity to adult and larval honey bees

and chronic toxicity to benthic invertebrates. There are no toxicity data available for

estuarine/marine fish and invertebrates. Tables 11

- 2 and 11

- 3 identify ecological effects studies that offer data for each gu ideline requirement and whether or not further data are needed in order to support risk assessment. In the absence of these data, the risk to the above organisms cannot be precluded and other lines of evidences may be used to estimate the potential risks as listed in the justification and assumption column in the t able s.

11.2.1 Justification for 10

- day Adult Chronic Toxicity Study Bees can be exposed to pes ticides through multiple pathways including contact with sprays and dusts and through ingestion of residues in food/water ( e.g ., pollen/nectar and water used to maintain colony temperature). Worker bees foraging on flowers for pollen and nectar can be

rep eatedly exposed to residues in pollen and nectar either through direct contamination of these matrices by foliar sprays

. Residues can in turn be brought back to bee colonies where in

- hive bees including young adult and developing brood ( i.e ., eggs, larvae and pupae) may be exposed. EPA guidance (USEPA 2014 b ) on assessing the risk of pesticides to bees identifies a suite of laboratory

- based studies intended t o serve as the foundation for screening chemical s for potential

acute and chronic exposure effects t o individual adult and larval bees. The 10

- day toxicity study with young adult bees provides no

- observed adverse effect level (NOAEL) and lowest

- observed adverse effect level (LOAEL) for assessing chronic effects. Data obtained from this study will be

use d in estimating chronic risk to individual adult bees. This is a non

- guideline study; an OECD protocol is expected to be available in October 2014. A protocol should be submitted to the Agency for review before commencing the study and should include pro visions for measuring

the concentratio n of triallate in the actual diet of the honeybee.

11.2.2 Justification for 21

- day Larval Toxicity Study

### 19

Developing bee brood ( i.e ., larvae and pupae) can be exposed to pesticides through residues brought back to the colony by worker bees foraging in areas where the pesticide has been applied. While larvae are typically fed royal or brood jelly during their early stages of development, worker bee (females) and drone (males) larvae are also fed pollen/honey (bee bread) direc tly by in

- hive nurse bees. EPA guidance (USEPA 2014 b ) on assessing the risk of pesticides to bees identifies a suite of laboratory

- based studies intended that serve as the foundation for screening chemical for potential acute and chronic effects to indivi dual adult and

larval bees. The 21

- day larval toxicity study under development by OECD provides both acute and chronic toxicity data on developing bee brood and will yield a median lethal dose (LD 50 

### ) for assessing acute toxicity during the early part of th e study as well as a 21

- day no

- observed adverse effect level (NOAEL) and lowest

- observed adverse effect level (LOAEL) for assessing

chronic effects. Alternatively, r egistrants may submit a separate acute (single dose) larval toxicity study following OECD Guideline 237 as well as the 21

- day repeat dose chronic toxicity study to address both acute and chronic larval endpoints . Effects on survival and development (adult bee emergence) from repeat exposures to the active ingredient will be used in estimating

chronic risk to individual brood. A protocol for the 21

- day larval toxicity test should be submitted to the Agency for review before commencing the study and should include provisions for measuring the concentration of triallate in the actual diet of the honeybee.

________________________________________________ Draft guidance for the 21

- day larval toxicity study is available at: http://www.oecd.o rg/env/ehs/testing/Draft_GD_honeybees_rep_exp_for_2nd_CR_25_November_2013.pdf

OECD Guideline 237 is available at: http://www.oecd

ilibrary.org/docserver/download/9713171e.pdf?expires=1407449911&id=id&accname=guest&checksum=E67BED

EB01DB12D815E858CB45A989FB

### 20

Table 11

- 2. Submitted Aquatic Ecological Effects Data for Triallate

OCSPP

Guideline Data

Requi rement Source

MRID Classification Are Data

Needed to

Conduct the

Risk

Assessment? Justification and Assumptions EPA Will Make in the Absence of Data

850.1010 Freshwater

invertebrate acute toxicity 41895601

00029470 Acceptable No

--

850.103 5 Saltwater

invertebrate acute toxicity No data NA Yes Saltwater invertebrate (mysid) acute toxicity data are required under 40 CFR Part 158 because the product is expected to enter the environment.

In the absence of the data, surrogate thiocarbamate herbicides

– starting with data for closely related pesticides and proceeding to data for less related pesticides

– may be used to characterize the triallate impact to saltwater invertebrates.

850.102 5

850.1045

850.1055 Saltwater

invertebrate acute toxicity No dat a NA Yes Saltwater invertebrate acute toxicity data are required under 40 CFR Part 158 because the product is expected to enter the environment. An invertebrate mollusk (oyster, penaeid or bivalve) test may be selected.

In the absence of the data, su rrogate thiocarbamate herbicides

– starting with data for closely related pesticides and proceeding to data for less related pesticides

– may be used to characterize the triallate impact to saltwater invertebrates.

850.1075 Freshwater fish

acute toxicity 00029469

(cold water) Acceptable No

--

00076889 (cold water)

Formulated

Product Acceptable

00083641 (warm water) Acceptable

00076890 (warm water)

Formulated

Product Acceptable

850.1075 Saltwater fish

acute toxicity No data NA Yes Saltwate r fish acute toxicity data are required under 40 CFR Part 158 if the product is expected to enter the environment

, (recommend the same saltwater fish species for acute and chronic studies).

### 21

OCSPP

Guideline Data

Requi rement Source

MRID Classification Are Data

Needed to

Conduct the

Risk

Assessment? Justification and Assumptions EPA Will Make in the Absence of Data

In the absence of the data, surrogate thiocarbamate herbicides

– starting with data for closely related pesticides and proceeding to data for less related pesticides

– may be used to characterize the triallate impact to saltwater fish.

850.1300 Freshwater

invertebrate life cycle 45775401 Acceptable No

--

850.1350 Saltwater

invertebrates life cycle No data NA Yes Saltwater invertebrate life cycle data are conditionally required under 40 CFR Part 158 if the product is expected to enter the environment.

In the absence of the data, surrogate thiocarbamate herbicid es

– starting with data for closely related pesticides and proceeding to data for less related pesticides

– may be used to characterize the triallate impact to saltwater invertebrate life cycle.

850.1400 Freshwater fish

early

- life stage 44660901 Acceptab le No

--

850.1400 Saltwater fish

early

- life stage No data NA Yes Saltwater fish early

- life stage data are conditionally required under 40 CFR Part 158 if the product is expected to enter the environment

, (recommend the same saltwater fish species for a cute and chronic studies).

In the absence of the data, surrogate thiocarbamate herbicides

– starting with data for closely related pesticides and proceeding to data for less related pesticides

– may be used to characterize the triallate impact to saltwate r fish early

- life stage.

Non

guideline Whole

sediment

invertebrates chronic toxicity No data NA Yes Chronic sediment invertebrate toxicity data are required under 40 CFR Part 158

if:

i. the half

- life of the pesticide in sediment if > 10 days in either the aerobic soil or aquatic metabolism studies and if any of the following exist:

A. The soil partition coefficient (Kd) is ≥ 50

B. The log Kow is ≥ 3.

C. The Koc is ≥ 1,000.

The half

- life of triallate in aerobic aquatic metabolism studies ranges from 64 to 74 days; t he log Kow of triallate is 4.55; and the Koc’s range from 1305 (sandy loam) to 2730 (silty loam).

Because the triallate is likely to be persistence in the sediment, chronic sediment tests with the midge Chironomus dilutus , freshwater amphipod Hyalella azteca

, and estuarine/marine amphipod Leptocheirus plumulosus are needed.

### 22

OCSPP

Guideline Data

Requi rement Source

MRID Classification Are Data

Needed to

Conduct the

Risk

Assessment? Justification and Assumptions EPA Will Make in the Absence of Data

As indicated in 40 CFR Part 158, the registrant is required to submit a protocol for approval prior to initiating the study until such time as the OCSPP 850 chronic

sediment testin g guidelines are published.

In the absence of the data, we will not preclude the risk to the sediment

- dwelling invertebrates. If it is possible, other chronic toxicity data for surrogate

thiocarbamate herbicides

– starting with data for closely related pesticides and proceeding to data for less related pesticides

– may be used to characterize the chronic toxicity of triallate to sediment

- dwelling invertebrates.

850.4400 Aquatic plant

toxicity test using Lemna

spp. 45653205 Acceptable No

--

850.4500 Algal toxicity 45653201

44700901 (green alga) Acceptable

Supplemental No

--

45653204 (marine diatom) Acceptable

45653203 (freshwater diatom) Acceptable

850.4550 Cyanobacteria

toxicity No data

(blue

- green alga) NA Yes Cyanobacteria toxicity data are required under 40 CFR Part 158

In the absence of the data, blue

- green alga data for surrogate thiocarbamate

herbicides

– starting with data for closely related pesticides and proceeding to data for less related pesticides

– may be used to charact erize the triallate impact to cyanobacteria. NA = not applicable

### 23

Table 11

- 3. Submitted Terrestrial Ecological Effects Data for Triallate

OCSPP

Guideline Data

Requirement Source

MRID Classification Are Data

Needed to

Conduct the

Risk

Assessment? Justifi cation and Assumptions EPA Will Make in the Absence of Data

850.2100 Avian oral

toxicity 00083035

(upland game) Acceptable No Acute oral toxicity data for a passerine species are required under the new 40 CFR Part 158. A study has not been submitted fo r this data requirement.

A guideline

- compliant passerine acute oral toxicity test is needed. Acute oral toxicity data are only available for one avian species ( i.e. , bobwhite quail). Passerine birds may utilize metabolic pathways that are different fr om larger

birds and therefore be more sensitive to triallate . Furthermore, passerines exhibit behavioral responses to pesticide dosing that are potential indicators of reduced fitness in the field ( e.g. , regurgitation of contaminated diet) even when

direc t biochemically

- mediated lethal toxicity is not apparent.

In the absence of the data, passerine toxicity data for surrogate thiocarbamate

herbicides

– starting with data for closely related pesticides and proceeding to data for less related pesticides

– may be used to characterize the acute toxicity

of triallate to passerine species. No data (passerine) NA Yes

850.2200 Avian dietary

toxicity 40370609

(upland game) Acceptable No

--

40730609 (waterfowl) Acceptable

850.2300 Avian

reproduction 44700701

(upland game) Acceptable No Data ( TGA I) are required on a waterfowl bird species to support all outdoor

end

- use product uses under the 40 CFR Part 158. A study has not been submitted for this data requirement. A guideline

- compliant waterfowl

r eproduction is needed.

In the absence of the data, the upland game bird may be used as surrogate species or other thiocarbamate herbicides

– starting with data for closely related pesticides and proceeding to data for less re lated pesticides, may be use d as surrogate pesticide to characterize the reproduction effects of triallate to waterfowl species. No data (waterfowl) NA Yes

### 24

OCSPP

Guideline Data

Requirement Source

MRID Classification Are Data

Needed to

Conduct the

Risk

Assessment? Justifi cation and Assumptions EPA Will Make in the Absence of Data

850.3020 Honey bee acute

contact toxicity 4 2304301 Acceptable No

--

Non

guideline Honey bee acute

oral toxicity 44700801 Acceptable No The “White Paper in Support of the Proposed Risk Assessment Process for Bees” as submitted to the FIFRA Scientific Advisory Panel 1 proposes a screening

- level risk assessment process that includes acute contact with adult bees, acute and chro nic oral toxicity tests with adult bees and with larval bees. Acute oral toxicity data with larval bee and chronic oral toxicity data with adult

and larval bee are not available.

Acute and chronic oral toxicity data with larval bee may be collected in a combined study. In the absence of these data, larval honey bee oral toxicity data for surrogate thiocarbamate herbicides

– starting with data for closely related pesticides and proceeding to data for less related pesticides

– may be

used to characterize the oral toxicity of triallate to honey bees. Honey bee adult

chronic oral toxicity No data NA Yes

Honey bee

larval acute oral toxicity No data NA Yes

Honey bee

larval chronic oral toxicity No data NA Yes

Non

guideline Earthworm

acute toxicit y 44581701 Supplemental No

--

850.4100 Seedling

Emergence and Seedling

Growth 42471801 Acceptable No

--

850.4150 Vegetative

Vigor 42471701 Acceptable No

--

NA = not applicable

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

- HQ

- OPP

- 2012

- 0543

- 0004

### 25



## 12 References

FAO 2000. Food and Agriculture Organization of the United Nat ions. FAO PESTICIDE

DISPOSAL SERIES 8. Assessing Soil Contamination: A Reference Manual. Appendix 2. Parameters of pesticides that influence processes in the soil. Editorial Group, FAO Information Division: Rome, 2000. http://www.fao.org/DOCREP/003/X2570E/X2570E00.htm

Majewski, M..S. and Capel, P.D; Pesticides in the environment: Distribution, Trends, and Governing Factors. U.S. Geological Survey. Open

- File Report 94

- 506. National Water Q uality Assessment Program (1995).

Smith, A.E., Kerr, L.A., and Caldwell, B. Volatility of ethalfluralin, trifluralin, and triallate from a field following surface treatments with granular formulations. Journal of Agric ultural and Food Chemistry. V. 45 (4) : 1473

- 1478 (1997).

USEPA 2001

. Reregistration Eligibility Document for Triallate Environmental Fate and Effects Chapter EPA

- HQ

- OPP

- 2009

- 0081. Office of Pesticide Programs, U.S. Environmental Protection Agency. March 2001.

USEPA 2009 a . Revised Sectio n 3 New Use Registration Request for Triallate (Far

- GO) as a Bermudagrass Seed Treatment Herbicide. Environmental Fate and Effects Division, Office of Pesticide Programs, U.S. Environmental Protection Agency. January 26, 2009, DPs 351896, 352259, 358774 )

.

USEPA 2009 b

. Revised Drinking Water Exposure Assessment to establish tolerances of triallate and its degradate 2,3,3

- trichloro

- 2

- propenesulfonic acid (TCPSA) on Bermuda grass grown for seed. Environmental Fate and Effects Division, Office of Pesticide Programs, U.S. Environmental Protection Agency. November 20, 2008, DP 358774 )

.

USEPA 2014 a . BEAD Chemical Profile (BCP) for Registration Review: Triallate (078802). Biological and Economic Analysis Division, Office of Pesticide Programs, U.S.

Envi ronmental Protection Agency. May 23, 2014.

USEPA 2014b. Guidance for Assessing Pesticide Risk to Bees. Office of Pesticide Programs, USEPA, Health Canada Pest Management Regulatory Agency and California Department of Pesticide Regulation. June 23, 201 4. 58 pages.

Cited Environmental Fate Studies

41497601 Burgess, D. (1989) Uptake, Depur ation, and Bioconcentration of carbon 14|

-

Triallate by Bluegill Sunfish (Lepomis macrochirus), Part I. (Part II: MSL

9549): Lab Project Number: MSL

- 9548. Un

- publish ed study prepared by Monsanto Agricultural Co. 396 p.

### 26

000 86400 Marvel, J.T.; Henshall, A.; Brightwell, B.B. (1973) Final Report on Avadex

BW Environmental Studies: Part 3: Photodecomposition Studies (Soil and Water) and Leaching through Soil: Agricultural Research Report No. 329. (Unpublished study received May 1, 1975 under 524

- 124; submitted by Monsanto Co., Washington, D.C.; CDL:120623

- E)

00144567 Keene, E. (1990) Monsanto Company Phase 3 Summary of MRID 00144567.

The Environmental Studies of Triallate: Monsanto RD # 618. Prepared by Monsanto Agricultural Products Co. 25 p.

42651101 Shepler, K.; Esti goy, L. (1993) Laboratory Volatility of (carbon 14)

- Triallate:

Lab Project Number: 399W: 1157. Unpublished study prepared by PTRL

West, Inc. 63 p.

46186001 Shepler, K.; Estigoy , L. (1995) Laboratory Volatility of (Carbon

- 14)

- Triallate.

Project Number: MSL/12582, 399W, R/D/1625. Unpublished study prepared by PTRL West, Inc. 63 p.

44715501 Mackie, J. (1998) The Aerobic Degradation of (carbon 14)

- Triallate in Natural

Sediment/Water Systems: Lab Project Number: 390990: MSL

- 15172. Unpublished study prepared by Inveresk Research. 70 p

44715502 Elliot, R.; Klemm, G. (1987) The Aquatic Metabolism of Triallate in Surface

Water: Lab Project Number: MSL 6162. Unpublished study prepared by Monsanto Company. 62 p.

44715601

40 117901 Mackie, J.; S aunders, L. (1998) The Degradation of (carbon 14)

- Triallate in

Soil Under Aerobic Conditions: Lab Project Number: 15908: MSL

- 15173. Unpublished study prepared by Inveresk Research. 88 p.

Allan, J.M. (1983) Analytical Residue Method for Triallate and the Sodium Salt of 2,3,3

- tri chloroprop

- 2

- ene Sulfonic Acid in Soil. 22 p.

Cited Ecological Effects Studies

000 83035 Fink, R.; Beavers, J.B .; Joiner, G.; et al. (1980) Final Report: Acute Oral LD50

--

Bobwhite Quail: Project No. 139

- 184. (Unpub lished study received Jan 29, 1981 under

524

- 124; prepared by Wildlife International, Ltd. and Washington College, submitted by Monsanto Co., Washington, D.C.; CDL:244201

- A)

40730609 Hinken, C.; Grimes, J. (1986) Triallate: A Dietary LC50 Study with the Mallard: Project

ID. 139

- 230. Unpublished study prepared by Wildlife International LTD. 24 p.

40370609 Grimes, J.; Jaber, M. (1986) Triallate: A Diet ary LC50 Study with the Bobwhite:

Project ID. 139

- 229. Unpublished study prepared by Wildlife International LTD. 24 p.

44700701 Beavers, J.; McCollough, C.; Jaber, M. (1990) Triallate Technical: A One Generation

Reproduction Study with the Northern Bobwh ite (Colinus virginianus): Lab Project

### 27 Number: R.D.1449: WL

- 88

- 346: 139

- 249. Unpublished study prepared by Wildlife International Ltd. 94 p.

000 76889 Thompson, C.M.; Griffen, J. (1981) Acute Toxicity of Fargo^(R)I EC (Lot No. TTBW

12012) (AB

- 80

- 525) to R ainbow Trout ( Salmo gairdneri ): Static Acute B ioassay Report # 26962. (Unpub lished study, including letter dated Mar 9, 1981 from R.B. Ole

- son to E.C. Spurrier, received May 18, 1981 under 524

- 124; pre

- pared by Analytical Bio Chemistry Laboratories, Inc. , submitted by Monsanto Co., Washington, D.C.;

CDL:245192

- A)

000 76890 Thompson, C.M.; Griffen, J. (1981) Acute Toxicity of Fargo (R)I EC (Lot No. TTBW

12012) (A B

- 80

- 526) to Bluegill Sunfish ( Lepomis macrochirus ): Static Acute Bioassay Report # 26963. (Un pub lished study, including letter dated Apr 15, 1981 from R.B.

Ole

- son to E.C. Spurrier, received May 18, 1981 under 524

- 124; pre

- pared by Analytical Bio Chemistry Laboratories, Inc., submitted by Monsanto Co., Washington, D.C.; CDL:245192

- B)

000 83641 Morrill, L.H. (1974) Acute Toxic ity of Avadex BW to Bluegill ( Lepomis macrochirus ).

(Unpublished study received Sep 18, 1978 under 524

- 124; prepared by Bionomics, EG & G, Inc., submit

- ted by Monsanto Co., Washington, D.C.; CDL:097416

- N)

000 29469 Thompso n, C.M.; Forbis, A.D.; Griffen, J.R.; et al. (1979) Acute Toxicity of Triallate

(AB

- 79

- 071) to Rainbow Trout ( Salmo ) gairdneri ): Static Acute Bioassay Report # 24010. (Unpub

- lished study received Mar 4, 1980 under 524

- 145; prepared by Analytical Bio Chemi stry Laboratories, Inc. in cooperation with U.S. Fish and Wildlife Service, s ubmitted by Monsanto Co., Wash ington, D.C.; CDL:241961

- B)

00 109746 Auletta, C.; Rinehart, W. (1979) Acute Oral Toxicity study in Rats: [Triallate]: Project

No. 4919

- 77. (Unpubli shed study received Oct 16, 1979 under 524

- 145; prepared by Bio/dynamics, Inc., submitted by Monsanto Co., Washington, DC; CDL:241271

- J)

00 144308 Kier, L.; Ribelin, W. (1984) Triallate Technical: A Two Generation Reproduction Study

in the Rat: Final Repor t: Report No. MSL

- 3651. Unpublished study prepared by Monsanto Co. 1254 p.

44660701 Blaszcak, D. (1998) Acute Oral Toxicity Study in Rats with Triallate: Lab Project

Number: R.D.1439: 96

- 1538: HU

- 96

- 249. Unpublished study prepared by Huntingdon

Life Scie nces. 84 p

000 29470 Thompson, C.M.; Forbis, A.D.; Oleson, F.B. (1979) Acute Toxicity of Tri allate

Technical (AB

- 79

- 073) to Daphnia_magna : Static Acute Bioassay Report # 24012. (Unpublished study received Mar 4, 1980 under 524

- 145; prepared by Analytical B io Chemistry Laboratories, Inc., submitted by Monsanto Co., Washington, D.C.;

CDL:241961

- C)

41895601 McNamara, P. (1990) Triallate

- the Chronic Toxicity to Daphnia magna Under Flow

through Conditions: Lab Project Number: SB

- 89

- 122: 1046. Unpublished study prepared by Springborn Laboratories, Inc. 64 p.

### 28

44660901 Drottar, K.; Swigert, J.; Krueger, H. (1998) Triallate: An Early Life

- Stage Toxicity Test

with the Rainbow Trout ( Oncorhynchus mykiss ): Lab Project Number: 139A

- 198B:

WL

- 96

- 278: R.D.1438. Unpublis hed study prepared by Wildlife International Ltd. 85 p.

45775401 Plantania, S.; Sutherland, C.; Krueger, H. (2002) Triallate: A Flow

- Through Life

- Cycle

Toxicity Test with the Cladoceran ( Daphnia magna ): Final Report: Lab Project

Number: RD 1590: 139A

- 284 A: WL

- 2001

- 165. Unpublished study prepared by Wildlife International, Ltd. 65 p. {OPPTS 850.1300}

42471701 Chetram, R. (1992) Tier 2 Vegetative Vigor Nontarget Phytotoxicity Study Using

Triallate: Lab Project Number: BL91

- 482: R.D. 1125: 0612

- 91

- 2. Unpub lished study prepared by Pan

- Agricultural Laboratories Inc. 205 p.

42471801 Chetram, R. (1992) Tier 2 Germination/Seedling Emergence Nontarget Phytotoxicity

Study Using Triallate: Lab Project Number: BL91

- 483|: 0612

- 91

- 1: R.D. 1126. Unpublished study pre pared by Pan

- Agricultural Laboratories Inc. 219 p.

44700901 Georgie, L.; Burgess, D.; Forbis, A. (1984) Acute Toxicity of Triallate to Selenastrum

capricornutum Printz: Lab Project Number: AB

- 84

- 409: 32358: 8004. Unpublished study prepared by Analytical Bio

- Chemistry Labs., Inc. 38 p.

45653201 Palmer, S.; Kendall, T.; Frueger, H. (2002) Triallate: A 96

- Hour Toxicity Test with the

Freshwater Alga ( Selenastrum capricornutum ) that Includes a Recovery Phase: Final Report: Lab Project Number: 139A

- 275: WL

- 20 00

- 252. Unpublished study prepared by Wildlife International, Ltd. 63 p. {OPPTS 850.5400}

45653203 Desjardins, D.; Kendall, T.; Krueger, H. (2002) Triallate: A 96

- Hour Toxicity Test with

the Freshwater Diatom ( Navicula pelliculosa ): Final Report: Lab Pro ject Number:

139A

- 285A: WL

- 2001

- 168. Unpublished study prepared by Wildlife International, Ltd. 56 p. {OPPTS 850.5400}

45653204 Desjardins, D.; Kendall, T.; Krueger, H. (2002) Triallate: A 96

- Hour Toxicity Test with

the Marine Diatom ( Skeletonema costatu m ): Final Report: Lab Project Number: 139A

286: WL

- 2001

- 167. Unpublished study prepared by Wildlife International, Ltd. 57 p. {OPPTS 850.5400}

45653205 Desjardins, D.; Kendall, T.; Krueger, H. (2002) Triallate: A 7

- Day Static

- Renewal

Toxicity Test with D uckweed ( Lemna gibba G3): Final Report: Lab Project Number:

139A

- 287: WL

- 2001

- 166: Unpublished study prepared by Wildlife International,Ltd. 53p. {OPPTS 850.4400}

42304301 Hoxter, K.; Lynn, S. (1992) Triallate: An Acute Contact Study with the Honey Bee: Lab

Project Number: R. D. 1091. Unpublished study prepared by Eildlife International LTD. 14 p.

44700801 Hoxter, K.; Bernard, W.; Beavers, J. (1993) Technical Grade Triallate: A Dietary LC50

Toxicity Study with the Honey Bee (Apis mellifera): Lab Project Number: WL

- 92

- 264:

RD 1450: 139

- 339. Unpublished study prepared by Wildlife International Ltd. 17 p.

### 29

44581701 Palmer, S.; Sulaiman, M.; Beavers, J. (1998) Triallate: An Acute Toxicity Study with

the Earthworm in an Artificial Soil Substrate: Lab Project Number: 139

- 425: WL

- 96

- 310. Unpublished study prepared by Wildlife International Ltd. 61 p.

### Appendix A: Summary of Triallate Labels

Use Product Name

/ EPA Reg # Maximum Single

Application Rate (lb a.i./A) Application

Timing1 Method of

Application Al lowed Geographical Areas

Winter wheat, Winter Barley

Far

- GO Herbicide

/ 10163

- 286 1.5 F

Broadcast,

g round b and

t reatment,

c hemigation CA, CO, ID, KS, MN, MT, NE, NV, ND, OR,

SD, UT, WA, WY Spring Wheat,

Duram Wheat 1 F or S

Barley 1.5 F or S

Triticale 1.5 F or S

Sugarbeet 1.5 F or S CO, ID, KS, MN, MT, NE, NV, ND, OR, SD, UT, WA, WY Peas, green, field dried, chickpeas, garbanzo beans 1.5 F,S

CA, CO, ID, KS, MN, MT, NE, NV, ND, OR,

S D, UT, WA, WY Lentils 1.5 F,S

Spring Wheat,

Duram Wheat 1 S

Barley 1.5 S

Triticale 1.5 S

Spring Wheat, Barley 1.52 F

Winter Wheat 1.25 F Spring Wheat, Durham Wheat, Barley 1.5 F or S

### 31 Use Product Name

/ EPA Reg # Maximum Single

Application Rate (lb a.i./A) Application

Timing1 Method of

Application Al lowed Geographical Areas

Winter Wheat, Winter Barley

Avadex MinTill

Herbicide

/ 10163

- 287 1.5 F

Ground application, air granule application CA, CO, ID, KS, MN, MT, NE, NV, ND, OR,

SD, UT, WA, WY

Sugar Beet 1.5 F or S CO, ID, KS, MN, MT, NE, NV, ND, OR, SD, UT, WA, WY

Spring Wheat,

Durham Wheat 13 F or S

CA, CO, ID, KS, MN, MT, NE, NV, ND, OR, SD, UT, WA, WY Spring Wheat,

Durham Wheat 1.25 F or S

Barley and

Triticale 1.25 F or S

Lentils 1.25 S

Bermuda Grass 1.5 F

Winter Wheat 1.5 F CA, CO, KS, NE, SD

Winter Wheat, Barley 1.5 F CA, ID, MT, OR, UT, WA

Spring Wheat, Durham Wheat, Barley 1.5 F or S CA, ID, MN, MT, ND, UT

Peas, green, field dried, chickpeas, garbanzo beans 1.25 S CA, CO, ID, KS, MN, MT, NE, NV, ND, OR, SD, UT, WA, WY

Barley
Buckle Granular

Herbicide 1.25 F or S CO, ID, KS, MN, MT, NE, NV, ND, OR, SD, UT, WA, WY Peas 1.25 F or S

### 32 Use Product Name

/ EPA Reg # Maximum Single

Application Rate (lb a.i./A) Application

Timing1 Method of

Application Al lowed Geographical Areas

Durham Wheat / 10163

- 289

1.25 F Ground granule application

Winter Wheat 1.5 F

Spring Wheat 1 F ND (Adams, Billings, Bottineau, Burleigh, Burke, Divide, Dunn, Emmons, Grant, Golden Valley, Hettinger, Kidder, McHenry, McKenzie, McLean, Mercer, Morton, Mountrail, Oliver, Renville, Sheridian, Sioux, Slope, Stark, Ward, and Williams Counties), SD (Corson, Dewey, Harding, Perking, Zlebach Counties)

Spring Wheat Buckle Granular

Herbicide

/ 10163

- 289 1 S Ground granule application SD (Corson, Dewey, Harding, Perking

Zeibach)

N/S 4 10163

- 288

Triallate Technical N/S N/S N/S N/S

1 Application allowed only o nce per growing season. Application can be made in either the F or S if listed as such. Application suggests 2 incorporations which can be made both in the Fall (if no spring tillage anticipated), in the Fall and in the spring (applied in fall) , or both in the spring (if applied in the spring) 2 Rate applies to fine textured soil only; otherwise 1.25 lb/A is required 3 If using disc press drills; otherwise max rate is 1.25 lb/A 4 N/S = Technical Grade labels; information not specified Application Key:

S = Spring

F = Fall F or S = Either Fall or Spring application

### 33 Appendix B : Environmental Transformation Products of Triallate

Table B

- 1. Environmental Transformation Products of Triallate

Code

Name/ Synonym Chemical Name/

Smiles Code Chemical Structure Study Type/ Corresponding OCSPP

Guideline MRID Maximum % AR (interval) 1

Major Degradate Minor (>10%) Transformation Products

-- Carbon dioxide CO 2 Aerobic Soil Metabolism

835.1200 00144567 28% (30 days)

44611302 Need blowbacks

44715601 44% (days 120)

Anaerobic Soil metabolism

835.4200 44611302 13.7 (90 days)

Aerobic Aquatic Metabolism 44 7 15501 4.35% (100 day)

Minor (<10%) Transformation Products

TCPSA 2,3,3

- trichloroprop

- 2ene sulfonic

acid

C(C(=C(CL)CL)CL)S(=O)(=O)O Aerobic Soil Metabolism

835.4200 00144567 3.4% (No DER)

44611302 3.4 (days 31)

44715601 3.74 (120 days)

Anaerobic Soil metabolism

835.4200 44611302 3. 8 (90 days)

1 Bold font indicates maximum concentration of degradate observed in various environmental fate studies.

2 No date mentioned in DER

### 34 Appendix C: Results of ECOSAR Modeling

The ECOSAR Programs is a screen

- level tool based chemical structure developed by the USEPA Office of Chemical Safety and Pollution Prevention for rapid screening of ch emicals for ecotoxicity hazards. The modeling results show that TCPSA, a minor degradate of triallate, becomes much less toxic than parent triallate after loss of the carbamate toxic moiety. The ECOSAR estimate values for triallate is similar to the expe rimental measured value.

Taxon Triallate ECOSAR Class (mg/L) Experimental

Measured Vinyl/Allyl Halides Thiocarbamate, Mono Neutral Organic SAR

Acute Chronic Acute Chronic Acute Chronic Acute Chronic

Fish 0.273 0.021 1.743 0.057 1.236 0.160 1. 2, 1.3 1.5, 2.4 0 .03 8

Daphnid 0.264 0.043 0.452 0.018 0.890 0.168 0.09

0.43 0.014 Green algae 0. 793 0.555 0.126 0.220 1.767 0.785 0.021

- Marine diatom

- - - - - - 0.33

- Saltwater Fish 0.117

- 0.621

- - - - - Saltwater Mysid 0.067

- 0.257

- - - - - Earthworm 256.7

- - - - - - -

Taxon TCPSA ECOSAR Class (mg/L)

Vinyl/Allyl Halides Neutral Organic SAR

Acute Chronic Acute Chronic

Fish 43346.95 82004.13 17296.14 1331.32 Daphnid 30128.90 11.41 8020.06 445.09 Green algae 23435.18 1891.95 2585.51 431.26

Saltwater Fish 46310.52

- - - Saltwater Mysid 20788.31

- - - Earthworm 4088.31

- - -

### Appendix D : Results of SIP and STIR



## SIP (v1.0)

Table 1. Inputs

Parameter Value

Chemical name T riallate
Solubility (in water at 25 o C; mg/L) 4

Mammalian LD 50 (mg/kg

- bw) 1100 Mammalian test species laboratory rat Body weight (g) of "other" mammalian species

Mammalian NOAEL (mg/kg

- bw) 7.5 1
Mammalian test species labora tory rat Body weight (g) of "other" mammalian species

Avian LD 50 (mg/kg

- bw) 2251 Avian test species northern bobwhite quail Body weight (g) of "other" avian species Mineau scaling factor 1.15

Mallard NOAEC (mg/kg

- diet) 3 160 Bobwhite quail NOAEC (mg/kg

- diet) 5620 NOAEC (mg/kg

- diet) for other bird species Body weight (g) of other avian species NOAEC (mg/kg

- diet) for 2nd other bird species Body weight (g) of 2nd other avian species

Table 2. Mammalia n Results

Parameter Acute Chronic Upper bound exposure (mg/kg

- bw) 0.6880 0.6880 Adjusted toxicity value (mg/kg

- bw) 846.0766 5.7687 Ratio of exposure to toxicity 0.0008 0.1193

Conclusion* Drinking water exposure alone is NOT a potential
concern for mammals Drinking water exposure alone is NOT a potential
concern for mammals

Table 3. Avian Results

Parameter Acute Chronic Upper bound exposure (mg/kg

- bw) 3.2400 3.2400 Adjusted toxicity value (mg/kg

- bw) 1621.6868 156.7757 Ratio of exposure to a cute toxicity 0.0020 0.0207

Conclusion* Drinking water exposure alone is NOT a potential
concern for birds Drinking water exposure alone is NOT a potential
concern for birds

1 The value was the chronic NOAEL because the acute NOAEL value was not availabl e,

*Conclusion is for drinking water exposure alone. This does not combine all routes of exposure. Therefore, when aggregated with other routes ( i.e ., diet, inhalation, dermal), pesticide exposure through drinking water may contribute to a total exposu re that has potential for effects to non

- target animals.

### 36



## STIR (v1.0)



# Welcome to the EFED Screening Tool for Inhalation Risk
This tool is designed to provide the risk assessor with a rapid method for determining the potential significance of the inhalation exposure route to birds and mammals in a risk assessment. 

## Input

Application and Chemical Information

Enter Chemical Name Triallate

Enter Chemical Use wheat Is the Application a Spray? (enter y or n) y If Spray What Type (ent er ground or air) ground Enter Chemical Molecular Weight (g/mole) 304.66 Enter Chemical Vapor Pressure (mmHg) 1.20E

- 04 Enter Application Rate (lb a.i./acre) 1.5

Toxicity Properties

Bird

Enter Lowest Bird Oral LD 50 (mg/kg bw) 2251

E nter Mineau Scaling Factor 1.15 Enter Tested Bird Weight (kg) 0.178

Mammal

Enter Lowest Rat Oral LD 50 (mg/kg bw) 1100

Enter Lowest Rat Inhalation LC 50 (mg/L) 5.3 Duration of Rat Inhalation Study (hrs) 4 Enter Rat Weight (kg) 0.35


## Out put
Results Avian (0.020 kg )
Maximum Vapor Concentration in Air at Saturation (mg/m 3 ) 1.97E+00

Maximum 1

- hour Vapor Inhalation Dose (mg/kg) 2.47E

- 01

Adjusted Inhalation LD 50 6.05E+01

Ratio of Vapor Dose to Adjusted Inhalation LD 50 4.0 9E

- 03 Exposure not Likely Significant

Maximum Post

- treatment Spray Inhalation Dose (mg/kg) 1.59E

- 01 Ratio of Droplet Inhalation Dose to Adjusted Inhalation

LD 50 2.62E

- 03 Exposure not Likely Significant 

### Results Mammalian (0.015 kg )
Maximum Vapor Concentration in Air at Saturation (mg/m 3 ) 1.97E+00

Maximum 1

- hour Vapor Inhalation Dose (mg/kg) 3.11E

- 01

Adjusted Inhalation LD 50 3.16E+02

Ratio of Vapor Dose to Adjusted Inhalation LD 50 9.85E

- 04 Exposure not Likely Significant

Maximum Post

- treatment Spray Inhalation Dose (mg/kg) 1.99E

- 01 Ratio of Droplet Inhalation Dose to Adjusted Inhalation

LD 50 6.31E

- 04 Exposure not Likely Significant