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

OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION 

### MEMORANDUM

DATE:

SUBJECT:

FROM:

THRU:

TO: 

### October 24, 2013

Registration Review- Preliminary Problem Formulation for the Ecological Risk Assessment and Drinking Water Exposure Assessment to be conducted for Fluthiacet-methyl (PC Code 108803; DP Barcode 412788)

Rochelle F. H. Bohaty, Ph.D., Chemist 

# \D\&4\**\~** Katherine R. Stebbins,

## Biologist**~** 1 

# d2J.(I**~** Environmental Risk Branch 3 Environmental Fate and Effects Division (7507P)

# ~~ Rosanna Louie-Juzwiak, 

# /n "'

_ "" Dana Spatz, Chiefs;::

# ~ 

# G-1

Environmental Risk Branch 3 

# U**~** 

### Environmental Fate and**Effect~** 

### Dtvision (7507P)

Ricardo Jones, Chemical Review Manager ' 

### Neil Anderson, Chief Risk Management and Implementation Branch 1 Pesticide Reevaluation Division (7508P)

The Environmental Fate and Effects Division (EFED) has completed the preliminary problem formulation (attached) for the ecological risk and drinking water exposure assessments to be conducted as part of the Registration Review offluthiacet-methyl. This document is intended to provide an overview of what is currently known regarding the environmental fate and ecological effects associated with fluthiacet-methyl and its degradation products, and outlines uncertainties regarding attributes of the parent compound and its transformation products. It 

### describes tlie preliminary ecological risk hypothesis and the processes that will be used during the completion of the ecological risk assessment in support of Registration Review.

1

### 2 1. INTRODUCTION

Fluthiacet-methyl is an herbicid e, predominantly used to control broadleaf weeds. It is a photobleaching imide herbicide in th e thiadiazole structural class. Fluthiacet-methyl is also in a class of herbicides known as light dependant peroxidizing herbicides (LDPH). LDPHs are a unique class of chemicals that can be more toxic in the pres ence of ultraviolet light. The chemical structure of fluthiacet-methyl along w ith the chemical identif iers are provided in Table 1

. Table 1. Fluthiacet-methyl Chemical Identifiers
Chemical Name Fluthiacet-methyl

Chemical Structure



### N N S N

O Cl

S

H 3 

### CO O F

Chemical Abstracts Service (CAS) Registry Number 117337-19-6

Smiles Notation C1CCCN2C(SC(N12)=NC3 =C(C=C(C(=C3)SCC(OC)=O)Cl)F)=O



### There are nine Section 3 registrations : eight end use products (279-9558, 279-9533, 279-9532, 279-3455, 279-3450, 279-3449, 279-3338, and 400-578), an d a technical formulation (279- 9550). Table 2 provides a summary of the flut hiacet-methyl formulated products.

Table 2. Fluthiacet-methyl Formulated Products

Product Name Use Site EPA Registration # Percent Active Ingredient Active Ingredient

BLIZZARD Cotton 400-578 10.3 Fluthiacet-methyl

F9328-1EC Corn, Cotton Soybean 279-9558 4.75 Fluthiacet-methyl 18.04 Carfentrazone-ethylFLUTHIACETMETHYL WSP Corn 279-9533 4.75 Fluthiacet-methyl

APPEAL EC HERBICIDE Corn, Soybean 279-9532 10.3 Fluthiacet-methyl
F9324-9 HERBICIDE Soybean 279-3455 1.2 Fluthiacet-methyl 30.08 Fomesafen

F9310-6 HERBICIDE Corn 279-3450 22.61 Pyroxasulfone 0.69 Fluthiacet-methyl

F9316-2 HERBICIDE Corn 279-3449 5.15 Pyroxasulfone 0.15 Fluthiacet-methyl 42.5 Atrazine

CADET HERBICIDE Corn, Soybean 279-3338 10.3 Fluthiacet-methyl

### 3 Fluthiacet-methyl is registered for use on corn, cotton and soyb ean. Fluthiacet-methyl usage has increased between 2007 and 2011 according a recent Bi ological and Economic Analysis Division (BEAD) report. 1 

### The highest use of fluthiacet-methyl is on soybean, followed by corn, and then cotton. The average annual application ra te is 0.003 lb a.i. /A for all crops.

Current label application rates fo r fluthiacet-methyl are listed in Table 3 . The application rates included on currently registered la bels are on a per season basis. Th e number of applications of fluthiacet-methyl that can be appl ied per year on a given field is not explicitly stated on current labels. The currently registered uses may result in multiple seasonal applications of fluthiacetmethyl per year as part of a crop rotation or plant back schedule.

Fluthiacet-methyl is not registered for any non-ag ricultural use sites.

1 Ratnayake, S., Haddad, Sepehr, Faulkner, J. BEAD Chemical Profile for Registration Review: Fluthiacet-methyl, May 28, 2013.4Table 3. Registered Fluthiacet-methyl Application RatesCrop/Site Residential Agricultural ForestryTiming;ApplicationTypeMethod/EquipmentMaximumSingleApplicationRate byFormulation(lb a.i./A)MaximumApplication RateMaximumApplicationNumber PHI (days) b REI (hours) b MRI (days) b Geographic RestrictionsCommentsPer Yearlb a.i./APer CCalb a.i./APerYearPerCCaCornPreplantBurndown;PostemergenceFoliarBroadcast/GroundAerial0.006 NS 0.009 NS NS 30c12dNS[3]eNSReg. 279-9558; do not applylater than 1 day after plantingcorn or soybeans.CottonDefoliate/DesiccateBroadcast/GroundAerial0.004 NS 0.009NS 2 7 12d6 NSThe application rate included inthe restriction section of 279-9558 (pg. 11) accepted June 8,2012 are listed as 0.044 (single)and 0.089 (per season) lbfluthiacet-methyl areinaccurate. The correct valuesbased on 0.51 lb fluthiacetmethyl in one gallon of product(pg. 3) and fluid ouncesallowed to be applied arereported in this table.SoybeanPreplantBurndown,Emergence;PostemergenceFoliarBroadcast/GroundAerial0.006 NS 0.009 NS NS 60 12dNS[3]eNSDo not apply during emergenceto v2 then applications allowedthrough v10a.Reported as per crop cycle or per seasonb.PHI – Preharvest interval; REI – reentry interval; MRI – Minimum retreatment intervalc.30 d (field corn forage); 70 d (field corn or popcorn gain or stover); 70 d (sweet corn stover)d.24 hour REI permitted for some applications rates.e.The label does not include an MRI; therefore,3 days will be assumed for assessment purposes.Boldfont indicates currently registered uses

### 5 1. PREVIOUS RISK ASSESSMENTS

Previous Ecological Assessments

Several ecological risk assessments have been completed for fluthiacet-methyl in recent years including anassessment for use as a defoliant in cotton (August, 2005) and assessments for new use patterns including aerial a nd pre-plant burndown applicati ons for corn and soybean uses (May 2010). EFED evaluated these assessments fo r fluthiacet-methyl in association with the current toxicity, exposure, and usage information to determine if sufficient data are available and if further updates are needed to support registration review.

Based on previous assessments, pot ential direct risk to terrestr ial and aquatic vascular and nonvascular plants from the use of fluthiacet-methyl is expected. Additionally, in the absence of chemical specific data on LDPH toxicity under e nhanced lighting, an interim adjustment factor of 29 X (EFED guidance) 2 

### will be applied to the chronic fi sh NOAEC. Based on this adjusted NOAEC, direct risk is anticipated for fish on a ch ronic exposure basis. Ther e is also the potential for various indirect effects on non-target animal speci es due to the effects on the plant and animal community (for example, depletion of food sources and habitat). The major conclusions presented in the previous chemical assessmen ts for fluthiacet-methyl are summarized in Table 4 and are briefly discussed in the subsections below.

Table 4. Summary of Risk Concerns Identified for Fluthiacet-methyl

Exposure

Basis Birds Mammals Terrestrial Plants Terrestrial Inverts. (honey

bee hazard) Fish Aquatic Inverts Aquatic Plants Ground water Contami

nation Persistence Degradates of Concern

Acute No No Yes (via drift) a No No No Yes a Yes b Yes b Yes b Chronic No No Yes c No

a. At least one LOC has been exceeded in previous assessments b. Fluthiacet-methyl quickly transforms to residues previously identified as residues of toxicological concern by the Health effects division. These residues are mobile and persistent.

c. Risk is anticipated after inclusion of a 29X toxicity adjustment factor.


### Previous assessments have not considered the po tential for more than one season per year. The registration review preliminary risk assessment will include modeling exposures to account for potential multiple crop cycles or crop rotations per year.

Previous Drinking Water Assessments

2 U.S.EPA. 2010. Interim Guidance on Light-dependant Peroxidizing Herbicides: Identification, DCI, Justification, and Use of a Toxicity Adjustment Factor on Fish Chronic Endpoints. Memorandum from D. Brady to the Environmental Fate and Effects Division. August 20, 2010

### 6 The most recentdrinking water assessment (DWA) completed for the currently registered fluthiacet-methyl uses was conducted in 2005. 3 

### Results of this assessment are summarized in Table 5

. Table 5. Fluthiacet-methyl Drinking Water Assessment Summary

Assessment Crop Tier II Surface Water Peak Concentration

μ g/L (ppb) Yearly Concentration Mean μ g/L (ppb) Average of Yearly Concentration

μ g/L (ppb)

DP304797 a Cotton 1.0 0.19 0.14
Tier II Groundwater Peak Concentration
μ g/L (ppb) Yearly Mean Concentration
μ g/L (ppb) 0.08 0.08

a. See footnote 

### Error! Bookmark not defined.

Clean Water Act Programs

Fluthiacet-methyl is not identif ied as a cause of impairment for any water bodies listed as impaired under section 303(d) of the Clean Wate r Act. No Total Maximum Daily Load (TMDL) criteria have been developed for fluthiacet-methyl. Aquatic Life Ambient Water Quality Criteria documents or Aquatic life benchmarks have not been published for fluthiacet-methyl.

2. ENVIRONMENTAL FATE AND TRANSPORT

Physical and Chemical Propert ies of Fluthiacet-methyl

The physicochemical properties of fluthiacet-methyl are shown in Table 6 . Based on these properties alone, fluthiacet-methyl is not expected to be volat ile or to bioaccumulate.

Table 6. Selected Physical/Chemical 

### Parameters of Fluthiacet-methyl

Parameter Value Source/Classification

Molecular formula C 15 H 15 ClFN 3 O 3 S 2 Calculated using ChemDraw

Molecular Weight 403.88 g/mol Calculated using ChemDraw

Vapor pressure (20°C) 2.57 x 10 -9 torr at 20  C; 3.31 x 10 -9 torr at 25  C MRID 43348403 Acceptable

Aqueous solubility (20  C) 0.85 mg/L in deionized water, mg/L 0.78 water at pH 5 and 7 MRID 43348403 Acceptable

Log octanol-to-water partition coefficient (log K O W ) 3.77 MRID 43348403 Acceptable

3 Moore, K., Frankenberry, M. Bohaty. R. Review of New Use for Fluthiacet methyl (Appeal EC; previously identified as - - CGA248757) as a defoliant in cotton., DP 3047970, August 24, 2005

### 7 Environmental Fate Propert ies of Fluthi acet-methyl

As part of this problem formulation, the submitted environmental fate data were reviewed and fate characterization updated along with modeling input parameters in ac cordance with current guidance documents. The updated parameters will be used in future exposure assessments.

The major routes of dissipation for fluthiacet-m ethyl are hydrolysis, pho tolysis and metabolism. The major route of transformation for fluthi acet-methyl is ester hydrolysis. The proposed fluthiacet-methyl environmental tran sformation scheme is presented in Figure 1 . This scheme highlights several major fluthiacet-methyl transformation produc ts including CGA-300402, CGA-300403, CGA-300404, CGA-3 27066, CGA-327067, and A-CFPSA. These transformation products are generally more stable and mobile th an parent fluthiacet-methyl. Environmental fate parameters of fluthiacet-methyl and total toxi c fluthiacet-methyl residues are presented in Table 7 and Table 8 . These parameters reflect the NAF TA degradation kinetics guidance. 4 

### Kinetic analyses are provided in APPENDIX A . A discussion of each environmental fate parameter is provided in the subsections below.

Hydrolysis

Fluthiacet-methyl hydrolysis is pH dependent. It has been shown to be stable to hydrolysis in acidic environments; however, as the pH increases so does the rate of hydrolysis. The primary hydrolysis product is the corresponding free aci d. The estimated hydrolysis half-life for fluthiacet-methyl at pH 9, 7, and 5 are appr oximately 5 hours, 19 days, and 483 days (well beyond the study duration), respectively.

The combined hydrolysis half-life of fluthiace t-methyl and the corresponding free acid (CGA300402) is much longer than the stu dy duration; however, an estimated half-life value for pH 7 is 315 days for the combined residues. A long term hydrolysis study would corroborate this value as well as confirm that additional residues of toxicological concern are not formed.

4 Guidance for Evaluating and Calculating Degradation Kinetics in Environmental Media , Health Canada, U.S. Environmental Protection Agency, December 2012.

### 8 N N S N

O Cl

S

H 3 CO O F

N N S N

O Cl

S

HO O F N N S N

O Cl

S

H 3 CO O F

O

N N S N

O Cl

S

HO O F

O

N N N

O Cl

S

HO O F S

N N N

O Cl

S

HO O F O

N N N

O Cl

S

HO O F O

O Fluthiacet-methyl CGA-248757

N N N

O Cl

S

HO O F S

O CGA-300402

(FA-9201) CGA-330057 (SO-9201)

CGA-300403

(FA-2602)

CGA-327066 (DeS-FA-2602) CGA-327067 (DeS-FA-SO-2602)

CGA-330059 (FA-SO-2602) CGA-300404 (FA-SO-9201)

HN Cl

S

HO O F O

O ACA-CFPSA H 2 N

H 2 N Cl

S

HO O F

O A-CFPSA

Figure 1. Proposed Fluthiacet-methyl Environmental Transformation Scheme; major transformation products shown in bold

### 9 Table 7. Environmental Fate Para meters of Fluthiacet-methyl

Study System Name/ Characteristics Kinetic Model Fitted 1 Value and Unit (Fitting Equation) Representative Half-life Value --Value Used to Derive Model Input Values

(days) 2
-- Source/ Classification Comments

DT50 (days) DT90 (days)

Hydrolysis pH 5, 25°C 483 (SFO) 1606 (SFO) 483 835.2010 MRID 43348447 Acceptable pH 7, 25°C 18.7 (SFO) 62.1(SFO) 18.7

pH 9, 25°C 0.195 (SFO) 0.649 (SFO) 0.195

Aqueous Photolysis pH 5, 25  C 5.7 (SFO) 18.7 (SFO) 5.7 MRIDs 43348448 and

43348449 Acceptable Half-life values
were not corrected for the dark control. Based on the study design solar intensity and 12 hour/day adjustments
were not necessary.

Soil Photolysis Madera loam soil (25oC, pH 6.7) 1.1(SFO) 3.5 (SFO) 1.1 MRIDs 43348450 and

43348451 Acceptable Half-life values are corrected for the dark control. Based on the study design solar intensity and 12 hour/day adjustments
were not necessary.

Aerobic

Soil Metabolism Madera loam soil (25oC, pH 6.7) 1.31 (SFO) 4.37 (SFO) 1.31 835.4100 MRIDs 43348452 and

43348453 Acceptable Combined labels—phenyl and pyridazinyl.

Only one soil is available.

Anaerobic Soil Metabolism Madera loam soil (25oC, pH 6.7) 0.73 (SFO) 2.42 (SFO) 0.73 MRIDs 43348454 and 43348455

Acceptable Half-life calculation is based on anaerobic phase only. Aerobic Aquatic No data

### 10 Anaerobic

Aquatic No data
Adsorption and

Desorption/ Batch Equilibrium Wisconsin Sand (pH 6.0, 0.13% OC, 2.2 CEC) 448 mL/g

OC MRID 43348456 Acceptable

Terrestrial Field

Dissipation Georgia and Illinois na MRID 43830026 Fluthiacet-methyl half-life was on the order of a few days. Most dissipation can be attributed to transformation mainly hydrolysis since it seems to be moisture dependent.

1 DT50 and DT90 values were calculated using nonlinear regression and single first-order (SFO), double first- order in parallel (DFOP), or indeterminate- order equation (IORE). For DFOP, the overall DT50 and DT90 are reported when available. Otherwise, a first and second DT50 are reported.
2 The value used to estimate a model input value is the calculated SFO DT 50 , T IORE , or the 2 nd DT 50 from the DFOP equation. The model chosen is consistent with that recommended using the Guidance for Evaluating and Calculating Degradation Kinetics in Environmental Media , Health Canada, U.S. Environmental Protection Agency, December 21, 2012. The same model used to estimate the value used to derive a model input, is used to describe the DT50 and DT90 results.

### 11 Table 8. Environmental Fate Parameters of Total Toxic Fluthiacet-methyl Residues (major transformation products) Conside red in Drinking Water Assessment

Study System Name/ Characteristics Kinetic Model Fitted 1 Value and Unit (Fitting

Equation) Representative Half-life Value --Value Used to Derive Model Input Values

(days) 2
-- Source/ Classification Comments

DT50 (days) DT90 (days)

Hydrolysis pH 7, 25°C 315 (SFO) 1045 (SFO) 315 835.2010 MRID 43348447 Acceptable

Aqueous Photolysis pH 5, 25  C 15.5 (SFO) 51.6 (SFO) 15.5 MRID 43348448 Acceptable Used data for phenyl labeled experiment only to capture all residues of concern. There are two unidentified components (MRID 43348448 ) that are observed in concentrations >10%. These components are considered part of the TTR since the residues were unidentified.

Soil Photolysis Madera loam soil (25oC, pH 6.7) 2.3 (SFO) 7.8 (SFO) 2.3 MRID 43348450 Acceptable Used data for phenyl labeled experiment only to capture all residues of concern. Values are corrected for the dark control. Based on the study design solar intensity and 12 hour/day adjustments were not necessary.

Aerobic Soil Metabolism Madera loam soil (25oC, pH 6.7) 7.94 (DFOP) 1950 (DFOP) 1030 835.4100 MRID 43348452 Acceptable Used data for phenyl labeled experiment only to capture all residues of concern. Only one soil is available. Representative half-life values is the half-life calculated based on the slow DFOP rate constant.

### 12 Anaerobic Soil

Metabolism Madera loam soil (25oC, pH 6.7) 8.2 304 -- MRIDs 43348454 and 43348455

Acceptable Representative half-life value is the half-life calculated based on the slow DFOP rate constant. Approximately 30% total toxic residues remained at study termination. Half-life calculation is based on anaerobic phase only. Aerobic Aquatic No data Anaerobic Aquatic No data
Study System Name/ Characteristics Parameter Values Source/ Classification Comments

Adsorption and

Desorption/ Batch Equilibrium CGA-300402: Wisconsin Sand (pH 6.0, 0.13% OC, 2.2 CEC), California Loam (pH 6.6, 0.65% OC, 17.0 CEC), Mississippi Silt Loam (pH 6.5, 0.79% OC, 9.7 CEC), Arizona Clay (pH 7.8, 0.86% OC, 47.5 CEC) 95, 169, 216, and 157 mL/g OC MRID 43348457 Acceptable

CGA-300403: Wisconsin Sand (pH 6.0, 0.13% OC, 2.2 CEC), California Loam (pH 6.6, 0.65% OC, 17.0 CEC), Mississippi Silt Loam (pH 6.5, 0.79% OC, 9.7 CEC), Arizona Clay (pH 7.8, 0.86% OC, 47.5 CEC) 40, 36, 66, and 40 mL/g OC MRID 43830021 Acceptable

CGA-300404: Wisconsin Sand (pH 6.0, 0.13% OC, 2.2 CEC), California Loam (pH 6.6, 0.65% OC, 17.0 CEC), Mississippi Silt Loam (pH 6.5, 0.79% OC, 9.7 CEC), Arizona Clay (pH 7.8, 0.86% OC, 47.5 CEC) 151, 112, 156, and 128 mL/g OC MRID 43830022 Acceptable

CGA-327066: Wisconsin Sand (pH 6.0, 0.13% OC, 2.2 CEC), California Loam (pH 6.6, 0.65% OC, 17.0 CEC), Mississippi Silt Loam (pH 6.5, 0.79% OC, 9.7 CEC), Arizona Clay (pH 7.8, 0.86% OC, 47.5 CEC) 25, 24, 45, and 27 mL/g OC MRID 43830023 Acceptable

CGA-327067: Wisconsin Sand (pH 6.0, 0.13% OC, 2.2 CEC), California Loam (pH 6.6, 0.65% OC, 17.0 CEC), Mississippi Silt Loam (pH 6.5, 0.79% OC, 9.7 CEC), Arizona Clay (pH 7.8, 0.86% OC, 47.5 CEC) 25, 18, 26, and 25 mL/g OC MRID 43830024 Acceptable

CGA-330057: Wisconsin Sand (pH 6.0, 0.13% OC, 2.2 CEC), California Loam (pH 6.6, 0.65% OC, 17.0 CEC), Mississippi Silt Loam (pH 6.5, 0.79% OC, 9.7 CEC), Arizona Clay (pH 7.8, 0.86% OC, 47.5 CEC) 498, 922, 1238, and 1114 mL/g OC MRID 43830025 Acceptable

1 DT50 and DT90 values were calculated using nonlinear regression and single first-order (SFO), double first- order in parallel ( DFOP), or indeterminate- order equation (IORE). For DFOP, the overall DT50 and DT90 are reported when available. Otherwise, a first and second DT50 are reported. 2 The value used to estimat e a model input value is the calculated SFO DT 50 , T IORE , or the 2 nd DT 50 from the DFOP equation.

### 13 Aquatic Photolysis

Aquatic photolysis of fluthiacet-met hyl was investigated in a sterile pH 5 buffered solution (acid condition minimizes fluthiacet-methyl hydrolysis). This study demonstrated that fl uthiacet-methyl is susceptible to aquatic photolysis. The estimated SFO ha lf-life is 5.7 days when transformati on data for fluthiacet-methyl from both radiolabeled experiments are consider ed as part of the kinetic analysis.

Several transformation products were observed to form as a result ofphotolysis; only CGA-300402 and CGA330057 were characterized quantitativel y. These residues are not unique photolysis transformation as these chemicals were observed in other laboratory studies. Two additional compounds were isolated at greater than 10% of the applied radioac tivity; however, these two compounds were not identif ied. Since these two residues cannot be ruled out as a residue of concern, the compounds were included in the total toxic residue calculation. The combined half-life of fluthiacet-methyl, CGA-300402 a nd the two unidentified residues is 15.5 days based on SFO kinetics.

Soil Photolysis

Fluthiacet-methyl was shown to undergo soil photolysis. The estimated half- life for parent only is 1 day based on SFO kinetics. This value reflects a correction factor adjustment for aerobic soil metabolism that occurs in the dark control.

Several residues were identifie d as transformation products (CGA-300402, CGA-330 057, CGA-300403, CGA300404, CGA-327066, CGA-330059, CGA-327067, and A-CFPSA) and none are unique to photolysis ( i.e. , the transformation products were observed in other laboratory studies). A SFO half-life of 2.3 days was estimated for total toxic fluthiacet-methyl residues.

Aerobic Soil Metabolism

The non-linear single first order (SFO) transformation half-life for fluthiace t-methyl was calculated to be 1.3 days in a Madera loam soil under aerobic conditions. Nine degradates were identified: CGA-300402, CGA330057, CGA-300403, CGA-300404, CGA-327066, CGA- 330059, CGA-327067, A-CFPSA and ACACFPSA. Degradates CGA-327067, AC A-CFPSA, and CGA-300404 were shown to be fairly persistent as little concentration decline was observed by the end ofthe study. The remaining degradates (CGA-300402, CGA330057, CGA-300403, CGA-327066, A-CFPSA) show ed formation and decline w ithin the study duration (360 days). The only major degradates we re CGA-300402, CGA-300403, CGA-327067, CGA-327066, and ACFPSA. The last two were only observed in th e phenyl-labeled study (MRID 43348452). The remaining degradates were minor degr adates with a formation of less than 10% . Approximately 24 other isolated organo soluble compounds were unidentified, none of which total more than 10% of the applied. Unextracted soil residues did not exceed an average maxi mum concentration of 10% of the applied. Volatiles totaled 1% of the applied.

Using a total toxic residue approach, the combined aerobic soil metabolism half-life of the toxic fluthiacetmethyl residues estimated using non-linear SFO and double fi rst-order in parallel (DFO P) kinetic models were 115 and 1030 days, respectively. These re sults reflect the stability of so me of the transformation products considered a residue of concern by the Health Effects Division.

Anaerobic Soil Metabolism

The half-life of fluthiacet-methyl was calculated to be less than one day using SFO kinetic model under anaerobic soil conditi on following an initia l aerobic phase.

### 14 Several transformation products (CGA- 300402, CGA-330057, CGA-300 403, CGA-300404, CGA-327066, CGA-330059, CGA-327067, A-CFPSA, and ACA-CFPSA) were observed. These transformation products were also identified in the aerobic soil metabolism studi es. The combined aerobic soil metabolism half-life of the toxic fluthiacet-methyl residues estimated using non-linear SFO and DFOP kine tic models were 28.4 and 140 days, respectively.

Batch Equilibrium

Batch equilibrium data suggest that fluthiacet-methyl is moderately mobile; however, fluthiacet-methyl was shown to transform under batch equilibrium conditions (on soil) to more mobile transformation products. Available data indicate that the mo st mobile of the fluthiacet-methyl transformation products is CGA-327067 which is considered mobile. Additional batch e quilibrium data are available for CGA-300404, CGA-327066, and CGA-330057, which indicate that al l of these transformati on products are more mob ile than the fluthiacetmethyl.

Field Dissipation

Field dissipation data are consistent with the results reported in the laboratory studies. Fluthiacet-methyl transforms quickly to several transf ormation products that are more pers istent and mobile than fluthiacetmethyl.

Bioconcentration

Fluthiacet-methyl was unstable under th e test conditions; however, it does not appear to accumulate. Numerous structurally similar transformation pr oducts including CGA-300402, CGA-300403, CGA-300404, CGA327066, and CGA-327067 were identified and quantified in fish tissues. A bi oconcentration factor (BCF) for parent only was not calculated: howev er, a BCF of 300 for whole fish was calculated for all residues (total radioactivity). This suggests that fluthiacet- methyl residues are not likely to accumulate.

Transformation Products

As mentioned above several fluthiacet-methyl tran sformation products were reported in the submitted environmental fate studies. These tr ansformation products are listed in APPENDIX B with the maximum amounts of each observed in the various environmental fa te studies. In the aqueous photolysis study submitted to EPA, there is a large amount of th e applied radioactivity that was not identified (component E and I), a major study deficiency.

3. RECEPTORS

Tables 10 and 11 provide a summary of the aquatic and terrestr ial taxonomic groups, respectively, and the most sensitive surrogate species tested to characterize the potential acute and chroni c ecological effect s of fluthiacetmethyl. The tables provide a preliminary overview of the potential acute toxicity of fluthiacet-methyl by providing the acute toxicity classifications. Based on the available ecot oxicity information, the organisms facing the greatest hazard are fish and aquatic and terrestrial plan ts. No toxicity data were submitted or identified in the open literature for the fluthiacet -methyl transformation products.

Fluthiacet-methyl is a ligh t dependant peroxidizing herbicide (LDPH) . LDPHs are a unique class of chemicals that can be more toxic in the presen ce of ultraviolet light. In the absenc e of chemical specific data on LDPH toxicity under enhanced lighting, an interim adjustment factor of 29 X is applied to the chronic fish NOAEC

### 15 (EFED guidance) 5 

### . An ELS study conducted under modified lighting ( i.e. enhanced uV ) with a low light “reference treatment” would reduce the uncertainty in this assessment by s upplying data for a chemical specific LDPH adjustment factor. While enha nced toxicity in the presence of uV light is not necessarily limited to aquatic fish and could be observed in other taxa such as aquatic invert ebrates, birds, mammals and plants 6 

### , at this time, the EPA is only applying an adjustment factor to fish. Data on the e ffects of enhanced lighting (compared to standard laboratory/gr eenhouse lighting) for other taxa w ould reduce the uncertainty in the
assessment.

Table 9. Summary of the Most Sensitive Endpoints fr om Aquatic Toxicity Studies for Fluthiacet-methyl

Taxonomic

Group Study Type Surrogate Species and Test Material Toxicity Value (all units in terms of

measured active ingredient) MRID and Classification Acute Toxicity Classification

Freshwater fish a Acute Rainbow Trout ( Oncorhynchus mykiss )

TGAI LC 50 = 43 μg a.i./L

NOAEC: 37 μg a.i./L based on mortality and sublethal effects (lethargy) Slope: NC 43357802 Acceptable Very highly toxic

Chronic (Early Life Stage) Fathead Minnow ( Pimephales promelas )

TGAI NOAEC = 2.7 μg a.i./L LOAEC = 6.0 μg a.i./L NOAEC with 29 X LDPH adjustment factor = 0.09 μg a.i./L Most sensitive endpoint: growth (length and weight) 43830009 Acceptable --

Estuarine/Marine fish Acute Sheepshead Minnow ( Cyprinodon variegatus )

TGAI LC 50 = 160 μg a.i./L

NOAEC: 92 μg a.i./L based on mortality and sublethal effects (loss of equilibrium). Slope: 11.9 43830006 Acceptable Highly toxic

Chronic No Data

Freshwater invertebrates Acute Water Flea ( Daphnia magna )

TGAI EC 50 = >2,300 μg a.i./L

No mortality or sublethal effects reported. Slope: N/A 43357803 Acceptable No more than moderately toxic

5 U.S.EPA. 2010. Interim Guidance on Light-dependant Peroxidizing Herbicides: Identification, DCI, Justification, and Use of a Toxicity Adjustment Factor on Fish Chronic Endpoints. Memorandum from D. Brady to the Environmental Fate and Effects Division. August 20, 2010

6 Birchfield, N.B., Casida, J.E. 1997. Protoporphyrinogen oxidase of mouse and maize: Target site selectivity and thiol effects o n peroxidizing herbicide action. Pesticide Biochemistry and Physiology . 57: 36-43.

### 16 Taxonomic

Group Study Type Surrogate Species and Test Material Toxicity Value (all units in terms of

measured active ingredient) MRID and Classification Acute Toxicity Classification

Chronic Water Flea ( Daphnia magna )

TGAI NOAEC = 35 μg a.i./L LOAEC = 70 μg a.i./L

Most sensitive endpoint: growth (length). 43830010 Acceptable --

Estuarine/Marine invertebrates Acute Mysid Shrimp ( Americamysis bahia ) TGAI EC 50 = 280 μg a.i./L

NOAEC: 130 μg a.i./L based on mortality. Slope: NC 43830007 Acceptable Highly toxic

Chronic No Data

Aquatic plants and algae Nonvascular Green Algae ( Pseudokirchneriella subcapitata b )

TGAI EC 50 = 2.51 μg a.i./L NOAEC = 0.40 μg a.i./L

Endpoint: cell density 43348443 Acceptable --

Vascular Duckweed ( Lemna gibba )

TGAI EC 50 = 1.4 μg a.i./L NOAEC = 0.065 μg a.i./L c

Endpoint: number of fronds 43348441 Acceptable --

a. Freshwater fish represent surrog ates for aquatic-phase amphibians. b. Formerly Selenastrum capricornutum

c. Negative control was compared with the test concentration in recalculated EC 50 and NOAEC with NUTHATCH continuous endpoint statistical analysis. Previous EC 50 and NOAEC calculations were done with probit regression analysis (with solvent contro l compared to test concentrations). NC= Not calculated because neither m oving average or probit analysis can give statistically sound results.

### 17 Table 10. Summary of the Most Sensitive Endpoints from Terrestrial Toxicity Studies for Fluthiacetmethyl

Taxonomic

Group Study Type Surrogate Species Toxicity Values (all units in terms of measured a.i.) MRID and Classification Acute Toxicity Classification

Mammals Acute Oral Laboratory rat ( Rattus norvegicus ) LD 50 >5000 mg/kg bw No mortality at any dosage 43348411 (Acceptable) Practically nontoxic c
Acute Inhalation Laboratory rat ( Rattus norvegicus ) LD 50 > 5.0 mg/L 43348413 (Acceptable) N/A

Chronic Laboratory rat ( Rattus norvegicus ) NOAEL 500 mg/kg-diet LOAEL= 5000 mg/kg-diet

Reproductive toxicity Endpoint: decreased mean litter body weights

The NOAEL for systemic toxicity is 25 ppm (1.59- 1.86 mg/kg/day) based on hepatic pathology (not an EFED endpoint) and equivocal reductions in male body weights/weight gain at 500ppm (31.8-37.1 mg/kg/day) 43830016 (Acceptable) N/A

Birds a Acute Oral Bobwhite quail Mallard (Colinus virginianus) (Anas platyrhynchos) LD 50 >2250 mg/kg bw

No mortality at any dosage 43348405 43348406 (Acceptable) Practically nontoxic c

Subacute Dietary Bobwhite quail Mallard (Colinus virginianus) (Anas platyrhynchos) LC 50 >5620 mg/kg-diet

43348407 43348408 (Acceptable) Practically nontoxic c Northern bobwhite: One mortality at a test dosage of 5620 ppm on day 5; Mallard: no mortality at any dosage

Bobwhite quail Mallard (Colinus virginianus) (Anas platyrhynchos) NOAEC = 100 mg/kg-diet LOAEC > 100 mg/kg-diet No treatment-related mortalities, treatment-related effects on body weight, overt signs of toxicity, or adverse reproductive effects at test concentrations up to 100
p pm, the highest dose tested. 100 ppm = 0.42 lb a.i./A application 43830005 43830004 (Supplemental) Chronic N/A

Terrestrial

Insects Acute Contact Honey Bee (Apis mellifera) LD 50 > 100 μg/bee No mortality at any dosage 43348445 (Acceptable) Practically nontoxic b

Terrestrial

Plants Vegetative Vigor Dicot-Tomato NOAEC: 0.000074 lb a.i./A 45376305 45376304 --

### 18 (TEP d + Adjuvant) EC 25 : = 0.00017 lb a.i./A Endpoint: Shoot weight (Acceptable)

Monocot-Onion NOAEC: 0.002 lb a.i./A EC 25 : 0.0062 lb ai/A Endpoint: Shoot weight

Seedling Emergence

(TGAI) Dicot-Tomato NOAEC: 0.006 lb a.i./A EC 25 : >0.018 lb a.i./A Endpoint: Phytotoxicity e 43348438 (Acceptable) -- Monocot-Onion NOAEC: 0.006 lb a.i./A EC 25 : 0.010 lb a.i./A Endpoint: Dry weight

a. Birds represent surrogates for terrestrial-phase amphibians and reptiles. b. Based on acute contact LD 50 ( μ g a.i./bee) <2 highly toxic; 2-10.99 moderately toxic; ≥ 11 practically non-toxic

c. Acute Oral (avian/mammal): Based on LD 50 (mg/kg) <10 very highly toxic; 10-50 highly toxic; 51-500 moderately toxic; 501-2000 slightly toxic; >2000 practically nontoxic d. Action II 0.9 EC plus adjuvant

e. The EC25 is a “greater than” value because phytotoxicity is not considered a quantitative endpoint N/A not applicable



### Degradate Toxicity

Toxicity data are not available for the transformation products (CGA-300402, CGA-300403, CGA-300404, CGA-327066, CGA-327067, A-CFPSA, ACA-CFPSA, CGA-330057, and CGA-330059 ). For two of the transformation products (CGA-300402 and CGA-327067), herbic idal efficacy screening data were submitted. While the data generally suggest that CGA-327067 is less toxic th an the parent compound and CGA-300402 has approximately equivalent toxici ty to the parent compound, these data are not robust enough to use quantitatively and there is uncertainty regarding the potential for CGA-300402 to be more toxic to certain species (there was more phytotoxicity to five of seventeen dicots based on approximate per cent suppression in the efficacy trial). To check for other toxicity data for the transformation products, a query of the European Pesticide Properties Database (PPDB) 7 

### was conducted; however, no studies were found on the degradation products. Additionally, a structure activity analysis (SAR) using ECOSAR (V1.1) was conducted, however, with this active ingredient, the SAR is of limited utility because th e output for the parent is not consistent with the empirical toxicity data (generally off by two orders of magnitude). In general, the SAR results do not show indications that the transfor mation products would be more toxic than the parent. See APPENDIX C for ECOSAR input/output.

Ecological Incidents

As of July 23, 2013, there were no incidents reported for fluthiacet-methyl in the Ecological Incident Information System (EIIS, version 2.1- maintained by the EPA- Office of Pesticide Programs), the Avian Monitoring Information System (AIMS- maintained by the American Bird Conservancy), or in the IDS Aggregate Incident Reports’ database (maintained by EPA).

4. EXPOSURE PATHWAYS OF CONCERN

Fluthiacet-methyl may reach surface wa ters through spray drift and penetr ation of the canopy during application and foliar wash-off to the soil, followed by runoff of flut hiacet-methyl sorbed soil or dissolved phase fluthiacetmethyl. Fluthiacet-methyl may also l each to groundwater. Field dissipation studies show that fluthiacet-methyl transforms very quickly in the environment—this redu ces the likelihood that fluthi acet-methyl will contaminate

7 PPDB. Pesticide Properties Database. University of Hertfo rdshire. http://sitem.herts. ac.uk/aeru/footprint/index2.htm

### 19 surface water or groundwater. However, in contrast, ae robic soil metabolism coupled with batch equilibrium data indicate fluthiacet-methyl transforms rapidly to mobile or highly mobile compounds. It is possible that such transformation products may contaminate surf ace water, as well as leach to groundwater.

The exposure pathways for fluthiacet-methyl and its tr ansformation products may result in a wide range of potential aquatic and terrestrial e xposure scenarios. For this problem formulation, the drinking water and inhalation pathways were screened using the SIP (Scr eening Imbibition Program) and STIR (Screening Tool for Inhalation Risk) screen ing methods and were found to be exposure pathways of low concern. However, it is noted that the screening analysis do not include aggregation with all othe r exposure pathways (dietary, dermal, inhalation, or drinking water), which t ogether, may contribute to a total expos ure that has a potential for effects to non-target animals. The risk characterization section will discusses the impact of the consideration of other routes of exposure that have been id entified as potentially important, and th e degree of certainty associated with screening-level risk assessment conclusions. SIP and STIR are described in detail at http://www.epa.gov/oppefed1/models/terre strial/index.htm and the SIP and STIR model outputs are available in APPENDIX D and E , respectively.

5. ANALYSIS PLAN

Drinking Water Assessment

A drinking water assessment may be upda ted or refined to support future human health dietary risk assessments of fluthiacet-methyl. The drinking water assessment will incorporate model estimates of fluthiacet-methyl and any transformation products of toxico logical concern in surf ace water and groundwater . Current residues of concern identified by the Health Effects Division ’s (HED) ROCKS (Residues of Concern Knowledge Subcommittee) include CGA- 300402, CGA-300403, CGA-327066, CGA-327067, and A-CFPSA (all major environmental transformation products). Reevaluation of th e residues of concern maybe considered if additional toxicity data becomes available; however, the final determination of the residues of concern for registration review will be made through consulta tion with the ROCKS. The registrati on review drinking water assessment will include the modeling results as well a summary of available surface water and groundwater monitoring data if available.

To account for total toxic residues, each relevant e nvironmental fate study (hydr olysis, aqueous photolysis, aerobic soil metabolism, etc.) will be us ed to calculate the amount of total t oxic residues presen t in each study at each sampling interval. If a tr ansformation product was not identified in one of the studies it will be assumed to be a toxic residue. The total concentrati ons at each sampling interval will be us ed to recalculate the rate constant and the corresponding half-life value for each study. These da ta will then be used to calculate modeling input parameters according to the current (the time when the assessment is completed) input parameter guidance. When there are no data available for the identified or unidentified transformation products, input values will be assumed to be equivalent to the pa rent value. If data are availabl e for both fluthiacet-methyl and the transformation products of toxicologi cal concern and the data cannot be combined, the most conservative plausible values will be used. This will be based on the assessor’s best judgment. Rationales for choosing each input parameter will be discussed in th e assessment. If a residue or concern is identified to have a different mode of toxicity or is substantially more toxic than the parent it wi ll be modeled sep arately if data are available.

The current models available for conducting drinki ng water assessment for su rface water include PRZM (Pesticide Root Zone Model, version 3.12.3, June 2006) and EXAMS (EXposure Analysis Modeling System, version 2.98.04.06, April 2005) models. PRZM will be used to simulate pesticide transport as a result of runoff and erosion from an agricultural field while EXAMS will be used to estimate environmental fate and transport of pesticides in the index reservoir. Measures of exposure will be based on maximum single and year (including multiple seasons per year) labeled app lication rates, minimum retreatment intervals, and conservative methods of application.

### 20 Currently, groundwater modeling is completed using SCI-GROW (Screening Concentration in Groundwater, version 2.3, August 8, 2003); however, PRZM-Groundwater (PRZM-GW ve rsion 1.0, December 11, 2012), using the GW-GUI (Graphical User Interface, version 1.0, December 11, 2012). is also available to refine groundwater exposure estimates. SCI-GROW is an empirical model based on a linear be st fit through 13 singleapplication groundwater studies. PRZM-GW can be used to simulate vertical pesticid e transport through the soil profile into an aquifer following appl ication to an agricultura l field. The PRZM scenarios used in groundwater simulations are representative of vul nerable sites—shallow unconfined aquifers under an agricultural field with leaching prone soil—and output values represent pesticid e concentrations that may be observed in drinking water resulting from the use of groundwater vulnerable to pesticide contamination as source water. The results are expected to represent the upper b ound values on the concentrations of t oxic residues that might be found in drinking water supplied by groundwater.

Ecological Risk Assessment



## Stressors of Concern

In order to address the risk hypothesi s, the potential for adverse effects on the environment will be estimated. The use profile, environmental fate, and ecological effect s of fluthiacet-methyl and its transformation products will be characterized and integrated to assess the overall risks. Based on visual inspection, all nine transformation products maintain struct ural characteristics that are indicative of LDPH ch emicals (as defined in the interim guidance memo—U.S. EPA, 2010). Therefore, in the absence of toxici ty data suggesting these transformation products are more or le ss toxic than the parent, the transfor mation products will be assumed to be as toxic as the parent and a total toxi c residues (TTR) approach (FIFRA SAP, 2008) 8 

### will be used to assess risk for terrestrial and aq uatic exposure analysis.

Risk quotients (RQs) will be derived for total toxic re sidues (fluthiacet-methyl a nd the transformation products listed above) by dividing estimated environmental concen trations (EECs) by the most sensitive endpoint from the relevant, available toxicity data for fluthiacet-methyl.

Measures of Exposure

In order to estimate risks of fluthiacet-methyl exposure to aquatic and terrestrial organisms, all exposure modeling and resulting risk conclusions will be made based on maximum application rates, application methods, and any mitigation measures specifically indicat ed on the label. The models that will be used to predict the estimated environmental concentrations (EECs) of fluthiacet-methyl are discussed on OPP’s model website. 9 

### These models include: PRZM (Pesticide Root Zone Model) and EXAMS (EXposure Analysis Modeling System), PRZM-groundwater (GW), AgDrift, AgDisp, T-REX, TerrPlant, SIP (Screening Imbibition Program), and STIR (Screening Tool for Inhalation Risk).

For fluthiacet-methyl, the predicted estimated environmen tal concentrations of total toxic fluthiacet-methyl residues will be used to calculate risk quotients. For th e T-REX model, we will assume that the default half-life value of 35 days for foliar residue dissipation will cap ture the parent and degrad ates, unless data becomes available to suggest that the 35-day half-life is inadequate.



## Measure of Effects

8 FIFRA Science Advisory Panel. 2008. Selected Issues Associated with the Risk Assessment Process for Pesticides with Persistent, Bioaccumulative, and Toxic Character istics. http://www.epa.g ov/scipoly/sap/meetings /2008/102808_mtg.htm

9 http://www.epa.gov/opp00001/science/models_pg.htm

### 21 Ecological effects data are used as measures of direct and indirect effects to bi ological receptors. Data are typically obtained from registrant-submitted studies or from literature studies identified by ECOTOX. The ECOTOX database provides more ecological effects data in an attempt to bridge existing data gaps. ECOTOX is a source for locating single chemical toxicity data a nd potential chemical mixture toxicity data for aquatic life, terrestrial plants, and wildlife. ECOTOX was cr eated and is maintained by the U.S. EPA, Office of Research and Development, and the National Health and Environmental Effects Research Laboratory's MidContinent Ecology Division.



## Integration of Exposure and Effects

Risk characterization is the integrat ion of exposure and ecological effects to determine the potential ecological risk from the use of pesticides and th e likelihood of direct and indirect eff ects to non-target organisms in aquatic and terrestrial habitats. For the assessm ent of risks, the risk quotient (RQ) method is used to compare exposure and measured toxicity values. EECs are divided by acute and chronic toxicity valu es. The resulting RQs are then compared to the Agency’s Levels of Concern (LOCs) (USEPA 2004). These criteria will be used to indicate when fluthiacet methyl use, as directed on the label, has the potentia l to cause adverse di rect or indirect effects to non-target organisms. In a ddition, any incident data from the EIIS , IDS, and AIMS will be considered as part of the risk characterization.



## Endangered Species Assessments

Consistent with the Agency’s responsibility under the Endangered Species Act (ESA), the Agency will evaluate exposure and potential risks to federa lly-listed threatened and/ or endangered (listed) species from registered uses of pesticides in registration review.


## Endocrine Disruptor Screening Program

Fluthiacet-methyl is not in cluded in the first group of 67 chemicals issued an order to conduct Tier 1 EDSP testing. For additional information on the ED SP program, visit http://www.epa.gov/endo/.

6. PRELIMINARY IDENTIFICATIO N OF DATA GAPS

Fate

Table 11 identifies the environmental fate studies submitted by the registrant, as well as study classifications and whether or not additional data ar e needed in order to su pport the registra tion review exposure assessments. Rationale for the additional datarequested is also presented.

### 22 Table 11. Submitted Environmental Fate Da ta for Chemical Fluthiacet-methyl

OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are data needed to conduct risk assessment? Comments

835.2120 Hydrolysis 43348447 acceptable no

835.2240 Aqueous photolysis 43348448 acceptable no Data for phenyl-labeled experiment will be used to capture all residues of concern when calculating TTRconcentrations and corresponding halflife values for modeling.

There are two unidentified components that are observed in concentrations >10%. These components will be considered part of the TTR unless the residues are unidentified.

835.2410 Soil photolysis 43348450 acceptable no Data for phenyl-labeled experiment will be used to capture all residues of concern when calculating TTRconcentrations and corresponding halflife values for modeling.

Values are corrected for the dark control. Based on the study design solar intensity and 12 hour/day adjustments were not necessary.

835.4100 Aerobic soil metabolism 43348452 Acceptable no Data for phenyl-labeled experiment will be used to capture all residues of concern when calculating TTRconcentrations and corresponding halflife values for modeling.

Representative half-life values is the half-life calculated based on the slow DFOP rate constant.

835.4200 Anaerobic soil metabolism 43348454 Acceptable

No Representative half-life value is the halflife calculated based on the slow DFOP
rate constant.

Approximately 30% total toxic residues remain at study termination.

Half-life calculation is based on anaerobic phase only. 43348455 Acceptable

835.4300 Aerobic aquatic metabolism no data yes

835.4400 Anaerobic aquatic metabolism no data yes

### 23 OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are data needed to conduct risk assessment? Comments

835.1230 835.1240 Adsorption/ desorption and leaching 43348457 Acceptable

no Mobility data available for all major transformation products. 43830021 Acceptable 43830022 Acceptable 43830023 Acceptable 43830024 Acceptable 43830025 Acceptable

835.1410 Volatility – laboratory No data no Fluthiacet-methyl is not expected to be volatile based on the reported vapor
pressure.

835.6100 Terrestrial field dissipation 43830026 In review no

850.6100 Analytical method in soil

and water No data yes

835.6200 Aquatic field dissipation No data no

165-4 (850.1730) Fish bioconcentration 44019901 Acceptable no



### Effects

Table 12 

### identifies the ecological effects studies, as well as study classifications and wh ether or not further data are needed in order to support risk assessment. Rationale for the additiona l data requested is presented below the tables. Table 12. Submitted Aquatic Ecologica l Effects Data for Fluthiacet-methyl

OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are data needed to conduct

risk assessment? Comments

850.1010 Freshwater invertebrate acute toxicity 43357803 Acceptable No --

43357803 Acceptable

850.1025 850.1035 850.1045 850.1055 Saltwater invertebrate acute toxicity 43830007 Acceptable No --

43830008 Acceptable

850.1075 Freshwater fish acute toxicity 43357802 Acceptable No --

43357801 Acceptable

850.1075 Saltwater fish acute toxicity 43830006 Acceptable No --

850.1300 Freshwater invertebrate

life cycle 43830010 Acceptable No --

### 24 OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are data needed to conduct

risk assessment? Comments

850.1350 Saltwater invertebrates

life cycle

No Data Yes Based on the acute toxi city data, fluthiacet methyl was considerably more toxic to estuarine/marine invertebrates. Additionally, the acute endpoint for the freshwater invertebrate was non-definitive, so an estimation using ACR is not possible. Therefore, a life cycle study with an estuarine/marine invertebrate is needed.

850.1400 Freshwater fish early-life stage 43830009 Acceptable Yes Fluthiacet-methyl is cla ssified as an LDPH herbicide. A fish ELS toxicity test using enhanced uV lighting was previously requested and has not been received.

850.1400 Saltwater fish early-life stage

No Data Yes Without data, risk to estuarine/marine fish is assumed based on using the freshwater fish as a surrogate. Use of an ACR for estimation is not possible because the available freshwater species from the acute and chronic toxicity tests are not within the same taxonomic order ( i.e. , the species tested on an acute exposure basis are the bluegill and rainbow trout and for chronic exposure the fathead minnow was the species tested).

An ELS study conducted under modified lighting (i.e. enhanced uV) with a low light “reference treatment” would reduce the uncertainty in this assessment by supplying a chronic endpoint for an E/M fish and also data for a chemical specifi c LDPH adjustment factor. 850.1500 Fish life cycle No Data No 850.4400 Aquatic plant growth: Tier II vascular plants 43348441 Acceptable

No 45376306

(TEP) Acceptable

850.5400 Aquatic Plant Growth: Tier II algae 43348443 Acceptable

No 43348440 Acceptable

43348442 Acceptable

43348444 Acceptable

### 25 Table 13. Submitted Terrestrial Ecological Effects Data for Fluthiacet-methyl

OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are data needed for risk assessment? Comments

850.2100 Avian oral toxicity 43348405 Acceptable

No Low toxicity to other avian species and low use rates suggest that risk to passerine species is unlikely to exceed levels of concern; therefore, passerine data are not needed at this time. 43348406 Acceptable

850.2200 Avian dietary toxicity 43348407 Acceptable No 43348408 Acceptable

850.2300 Avian reproduction 43830005 Supplemental No 43830004 Supplemental

Nonguideline Avian inhalation No data No

81-1 Acute mammalian oral LD 50 (rat) 43348411 Acceptable No

83-4 Mammalian Reproduction (rat) 43830016 Acceptable No

850.3020 Honey bee acute contact toxicity No data No

Nonguideline Honey bee acute oral toxicity 43348445 Acceptable No

850.3030 Honey bee residue on foliage No data No

850.3040 Field testing for pollinators No data No

850.4100 Terrestrial plant toxicity: Tier II seedling
emergence

43348438 Supplemental (TGAI) Yes Data are needed for the End Use product +adjuvant, rather than the TGAI. Adding fullspectrum uV is recommended to reduce the uncertainty regarding the differences in greenhouse/laboratory lighting and natural sunlight.

Data are needed for the major degradate CGA-300402 because it was more toxic than the parent for 5 of the 17 dicots that were tested in the submitted herbicidal efficacy screening studies. 850.4150 Terrestrial plant toxicity: Tier II vegetative vigor 43348439 Supplemental (TGAI)
Yes For the End Use product + adjuvant, data are only available for 3 out of the 10 recommended species; therefore, a toxicity test for the remaining species is needed. Adding full-spectrum uV is recommended to 45376304 Acceptable for the 3 species provided (TEP)

### 26 OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are data needed for risk assessment? Comments

45376305 Acceptable for the 3 species provided (TEP) reduce the uncertainty regarding the differences in greenhou se/laboratory lighting and natural sunlight.

Data are needed for the major degradate CGA-300402 because it was more toxic than the parent for 5 of the 17 dicots that were tested in the submitted herbicidal efficacy screening studies.

124-1 Terrestrial Plant Field Testing No data No

124-2 Aquatic Plant Field Testing No data No



### Additional effects information that woul d be useful to the Agency include: 1. ecological incidents (non-target plant damage a nd avian, fish, reptilian, amphibian and mammalian mortalities) not already reported to the Agency 2. major degradate toxicity data

### 27 APPENDIX A

Kinetic Analysis Images Hydrolysis Parent

Total Toxic Residues

### 28 Aquatic Photolysis Parent Combined-label Irradiated

Total Toxic Residues Phenyl-label Irradiated

### 29 Soil Photolysis Parent Pyridazinyl-label Non-irradiated

Pyridazinyl-label Irradiated

Adjustment (parent) k (photolysis-pyridazinyl)=1.65 (irradia ted SFO)-1 (non-irradiated SFO)=0.65 ln(2)/0.65=1.1 days

### 30 Parent Phenyl-label Non-irradiated

Parent Phenyl-label Irradiated

Adjustment (parent) k (photolysis-phenyl)=2.2 (irradiate d SFO)-1.55 (non-irradiated SFO)=0.65 ln(2)/0.65=1.1 days

### 31 Total Toxic Residues Phenyl-label Non-irradiated

Phenyl-label Irradiated

Adjustment (TTR) k (photolysis-phenyl)=0.332(irradiated SFO)-0.0361(non-irradiated SFO)=0.65 ln(2)/0.30=2.34 days

### 32 Aerobic Soil Metabolism

Parent Combined-labels

Total Toxic Residues Phenyl-label

### 33 Anaerobic Soil Metabolism Parent Combined-labels

Total Toxic Residues Phenyl-label

### 34 APPENDIX B

Table 14. Summary of Fluthiacet-m ethyl Environmental Transformation Products

Code Name/

Synonym Chemical Name Study Type MRID/ Classification Maximum %AR (day) Final %AR (study length) CGA-300402;
FA-9201
“free acid”



### N N S N

O Cl

S

HO O F

[[2-chloro-4-fluoro-5- (tetrahydro- 6-hydroxy-3-oxo-1- thiooxo-1 H - [1.2,4 ]triazolo[1,2- a] pyridazin- (3 H )-yl)phenylthio] acetic acid

Formula: C 14 H 13 ClFN 3 O 3 S 2

MW: 389.8527 g/mol SMILES: C1CCCN2C(=O)SC(N12)=NC3 =CC(=C(C=C3F)Cl)SCC(O[H]) =O 835.2120 Hydrolysis 43348447 Acceptable pH 5 2.97 (30 d) 2.97 (30 d) pH 7 65.33 (30 d) 65.33 (30 d) pH 9 90.34 (3 d) 80.70 (30 d)

835.2240 Aqueous photolysis 43348448 Acceptable phenyl label 0.48 (23 d) 0.21 (30 d)

43348449 Acceptable pyridazinyl label 0.43 (30 d) 0.43 (30 d)

835.2410 Soil photolysis 43348450 Acceptable Medera loam phenyl label 54.0 (1 d) 2.3 (30 d)

43348451 Acceptable Medera loam pyridazinyl label 50.0 (1 d) 6.4 (30 d)

835.4100 Aerobic soil metabolism 43348452 Acceptable Medera loam phenyl label 55.1 (2 d) 0.1 (360 d)

43348453 Acceptable Medera loam pyridazinyl label 52.6 (2 d) 0.4 (360 d)

835.4200 Anaerobic soil metabolism 43348454 Acceptable Medera loam phenyl label 64.6 (1 d) 2.2 (60 d)

43348455 Acceptable Medera loam pyridazinyl label 65.0 (1 d) 3.1 (60 d)

CGA-330057;
SO-9201



### N N S N

O Cl

S

H 3 

### CO O F

O

2-Chloro-4-fluoro-5-(3-oxotetrahydro- [1,3,4]thiadiazolo[3,4- a]pyridazin-1-ylideneamino)- benzenesulfinyl]-acetic acid methyl ester

Formula: C 15 H 15 ClFN 3 O 4 S 2 MW: 419.8787 g/mol SMILES: C1CCCN2C(=O)SC(N12)=NC3 =CC(=C(C=C3F)Cl)S(CC(OC)= O)=O 835.2120 Hydrolysis 43348447 Acceptable pH 5 3.19 (21 d) 2.90 (30 d) pH 7 2.59 (0 d) ND pH 9 0.70 (0 d) ND

835.2410 Soil photolysis 43348450 Acceptable Medera loam phenyl label 2.0 (0.5 d) 1.3 (30 d)

43348451 Acceptable Medera loam pyridazinyl label 1.4 (1, 4 d) 1.1 (30 d)

835.4100 Aerobic soil metabolism 43348452 Acceptable Medera loam phenyl label 6.5 (14 d) 0.1 (360 d)

43348453 Acceptable Medera loam pyridazinyl label 4.7 (14 d) 0.1 (360 d)

835.4200 Anaerobic soil metabolism 43348454 Acceptable Medera loam phenyl label 6.3 (15 d) 0.6 (60 d)

43348455 Acceptable Medera loam pyridazinyl label 8.6 (15 d) 0.4 (60 d)

### 35 Code Name/

Synonym Chemical Name Study Type MRID/ Classification Maximum %AR (day) Final %AR (study length)

CGA-300403 FA-2602

N N N

O Cl

S

H O O F S

[[2-chloro-4-fl uoro-5-( tetrahydro- 6-hydroxy-3-oxo-1- thiooxo-1 H - [1.2,4) triazolo[1,2- a] pyridazin-(3 H )- phenyl]sulfinyl] acetic acid a

Formula: C 14 H 13 ClFN 3 O 3 S 2 MW: 389.8527 g/mol SMILES: C1CCCN2C(=O)N(C(N12)=S)C 3=CC(=C(C=C3F)Cl)SCC(=O) O[H] 835.2120 Hydrolysis 43348447 acceptable pH 5 NR NR pH 7 NR NR pH 9 1.76 (21 d) 0.89 (30 d)

835.2410 Soil photolysis 43348450 Acceptable Medera loam phenyl label 4.2 (21 d) 2.4 (30 d)

43348451 Acceptable Medera loam pyridazinyl label 5.0 (30 d) 5.0 (30 d)

835.4100 Aerobic soil metabolism 43348452 acceptable Medera loam phenyl label 20.8 (14 d) 1.1 (360 d)

43348453 acceptable Medera loam pyridazinyl label 18.5 (30 d) 1.0 (360 d)

835.4200 Anaerobic soil metabolism 43348454 Acceptable Medera loam phenyl label 10.6 (15 d) 2.8 (60 d)

43348455 Acceptable Medera loam pyridazinyl label 13.3 (15 d) 1.6 (60 d)

CGA-300404 FA-SO-9201



### N N S N

O Cl

S

HO O F

O



### [ 2-Chloro-4-fluoro-5-(3-oxotetrahydro- [1,3,4]thiadiazolo[3,4- a]pyridazin-1-ylideneamino)- benzenesulfinyl]-acetic acid

Formula: C 14 H 13 ClFN 3 O 4 S 2 MW: 405.8521 g/mol SMILES: C1CCCN2C(=O)SC(N12)=NC3 =CC(=C(C=C3F)Cl)S(CC(O[H]) =O)=O 835.2120 Hydrolysis 43348447 acceptable pH 5 NR NR pH 7 2.25 (21 d) 1.55 (30 d) pH 9 4.51 (1 d) 2.77 ( 30 d)

835.2410 Soil photolysis 43348450 Acceptable Medera loam phenyl label 41.6 (4 d) 5.3 (30 d)

43348451 Acceptable Medera loam pyridazinyl label 42.2 (11 d) 10.7(30 d)

835.4100 Aerobic soil metabolism 43348452 acceptable Medera loam phenyl label 2.0 (7 d) 1.0 (360 d)

43348453 acceptable Medera loam pyridazinyl label 1.8 (7 d) 0.7 (360 d)

835.4200 Anaerobic soil metabolism 43348454 Acceptable Medera loam phenyl label 4.4 (2.5 d) 3.1 (60 d)

43348455 Acceptable Medera loam pyridazinyl label 3.2 (60 d) 3.2 (60 d)

### 36 Code Name/

Synonym Chemical Name Study Type MRID/ Classification Maximum %AR (day) Final %AR (study length)

CGA-327066 DeS-FA-2602

N N N

O Cl

S

H O O F O

[[2-chloro-4-fluoro-5-( tetrahydro-1 ,3-dioxo-1 H -[1,2,4]triazolo[[ 1,2-a ]pyridazin2(3 H )-yl) phenyl]thio]acetic acid

Formula: C 14 H 13 ClFN 3 O 4 S

MW: 373.7871 g/mol SMILES: C1CCCN2C(=O)N(C(N12)=O) C3=CC(=C(C=C3F)Cl)SCC(=O) O[H] 835.2410 Soil photolysis 43348450 Acceptable Medera loam phenyl label 9.7 (21 d) 6.6 (30 d)

43348451 Acceptable Medera loam pyridazinyl label 3.8 (30 d) 3.8 (30 d)

835.4100 Aerobic soil metabolism 43348452 acceptable Medera loam phenyl label 11.8 (120 d) 5.7 (360 d)

43348453 acceptable Medera loam pyridazinyl label 8.8 (183 d) 6.0 (360 d)

835.4200 Anaerobic soil metabolism 43348454 Acceptable Medera loam phenyl label 8.6 (15 d) 4.8 (60 d)

43348455 Acceptable Medera loam pyridazinyl label 5.8 (30 d) 4.2 (60d)

CGA-330059 FA-SO-2602

N N N

O Cl

S

H O O F S

O

[2-Chloro-4-fluoro-5-(1-oxo-3- thioxo-tetrahydro- [1,2,4]triazolo[1,2-a]pyridazin-2- yl)-benzenesulfinyl]-acetic acid

Formula: C 14 H 13 ClFN 3 O 4 S 2 MW: 405.8521 g/mol SMILES: C1CCCN2C(=O)N(C(N12)=S)C 3=CC(=C(C=C3F)Cl)S(CC(=O) O[H])=O 835.2120 Hydrolysis 43348447 acceptable pH 5 NR NR pH 7 4.0 (12 d) ND pH 9 0.78 (30 d) 0.78 (30 d)

835.2410 Soil photolysis 43348450 Acceptable Medera loam phenyl label 3.9 (30 d) 3.9 (30 d)

43348451 Acceptable Medera loam pyridazinyl label 2.0 (21 d) 1.3 (30 d)

835.4100 Aerobic soil metabolism 43348452 acceptable Medera loam phenyl label 5.1 (60, 120 d) 2.0 (360 d)

43348453 acceptable Medera loam pyridazinyl label 5.2 (120 d) 2.4 (360 d)

835.4200 Anaerobic soil metabolism 43348454 Acceptable Medera loam phenyl label 4.0 (30 d) 3.0 (60 d)

43348455 Acceptable Medera loam pyridazinyl label 4.3 (30 d) 2.6 (60 d)

### 37 Code Name/

Synonym Chemical Name Study Type MRID/ Classification Maximum %AR (day) Final %AR (study length)

CGA-327067DeS-FA-SO2602

N N N

O Cl

S

H O O F O

O

[[2-chloro-4-fluoro-5- (tetrahydro-6-hydroxy-3-oxo-1- thiooxo-1 H -[1,2,4] triazolo[1,2- a] pyridazin-(3 H )- phenyl]sulfinyl] acetic acid

Formula: C 14 H 13 ClFN 3 O 5 S MW: 389.7865 g/mol SMILES: C1CCCN2C(N(C(N12)=O)C3= CC(=C(C=C3F)Cl)S(CC(=O)O[ H])=O)=O 835.2410 Soil photolysis 43348450 Acceptable Medera loam phenyl label 3.2 (21 d) 2.6 (30 d)

43348451 Acceptable Medera loam pyridazinyl label 2.1 (21 d) 1.6 (30 d)

835.4100 Aerobic soil metabolism 43348452 acceptable Medera loam phenyl label 13.4 (270 d) 13.2 (360 d)
43348453 acceptable Medera loam pyridazinyl label 12.1 (360 d) 12.1 (360 d)

835.4200 Anaerobic soil metabolism 43348454 Acceptable Medera loam phenyl label 8.7 (60 d) 8.7 (60 d)

43348455 Acceptable Medera loam pyridazinyl label 7.2 (60 d) 7.2 (60 d)

Unknown 835.2120 Hydrolysis 43348447 acceptable pH 5 NR NR pH 7 5.7 (17 d) 3.28 (30 d) Component E 835.2240 Aqueous photolysis 43348448 Acceptable phenyl label 15.73 (16 d) 8.26 (30 d)

43348449 Acceptable pyridazinyl label 26.96 b (16 d) 9.48 (30 d)
Component I 835.2240 Aqueous photolysis 43348448 Acceptable phenyl label 23.00 (16 d) 16.26 (30 d)

43348449 Acceptable pyridazinyl label 10.46 (30 d) 10.46 (30 d)

A-CFPSA

H 2 N Cl

S

HO O F

O

(5-Amino-2-chloro-4-fluorobenzenesulfinyl)-acetic acid

Formula: C 8 H 7 ClFNO 3 S MW: 251.66 g/mol SMILES: C1(=CC(=C(C=C1F)Cl)S(CC(= O)O[H])=O)N([H])[H] 835.2410 Soil photolysis 43348450 Acceptable Medera loam phenyl label 12.2 (11 d) 3.6 (30 d)

835.4100 Aerobic soil metabolism 43348452 Acceptable Medera loam phenyl label 11.9 (183, 270 d) 8.6 (360 d)

835.4200 Anaerobic soil metabolism 43348454 Acceptable Medera loam phenyl label 15.5 (45 d) 14.0 (60 d)

### 38 Code Name/

Synonym Chemical Name Study Type MRID/ Classification Maximum %AR (day) Final %AR (study length)

ACA-CFPSA

HN Cl

S

H O O F O

O H 2 N

(2-Chloro-4-fluoro-5-ureidobenzenesulfinyl)-acetic acid

Formula: C 9 H 8 ClFN 2 O 4 S MW: 294.69 g/mol SMILES: C1(=CC(=C(C=C1F)Cl)S(CC(= O)O[H])=O)N(C(N([H])[H])=O) [H] 835.4100 Aerobic soil metabolism 43348452 Acceptable Medera loam phenyl label 8.8 (360 d) 8.8 (360 d)

835.4200 Anaerobic soil metabolism 43348454 Acceptable Medera loam phenyl label 2.0 (60 d) 2.0 (60 d)

a. CGA-300403 IS a rearra ngement of the thiadi azolo pyridazin ring. It is not a sulfinyl (sulfoxide), because the thioether link b etween the phenyl ring and the acetic acid group is preserved. The code CGA-330059 was assigned to the sulfinyl (sulfoxide) of the rearrangement product CGA-300403. b. Values reported as “outlier”

### 39 APPENDIX C

ECOSAR Analysis

Parent CGA-248757 ECOSAR Version 1.10 Results Page SMILES : C1CCCN2C(=O)(SC(N12) =Nc3c(cc(c(c3)SCC(=O)(OC))CL)F) CHEM : CAS Num: ChemID1: MOL FOR: C15 H15 CL1 F1 N3 O3 S2 MOL WT : 403.88 Log Kow: 2.589 (EPISuite Kowwin v1.68 Estimate) Log Kow: (User Entered) Log Kow: 3.77 (PhysProp DB exp value - for comparison only) Melt Pt: (User Entered for Wat Sol estimate) Melt Pt: 106.00 (deg C, PhysProp DB exp value for Wat Sol est) Wat Sol: 4.642 (mg/L, EP ISuite WSKowwin v1.43 Estimate) Wat Sol: (User Entered) Wat Sol: 0.85 (mg/L, PhysProp DB exp value)

-------------------------------------- Values used to Generate ECOSAR Profile

-------------------------------------- Log Kow: 2.589 (EPISuite Kowwin v1.68 Estimate) Wat Sol: 0.85 (mg/L, PhysProp DB exp value)

-------------------------------------- ECOSAR v1.1 Class-specific Estimations

-------------------------------------- Hydrazines Thiocarbamates, Mono Predicted ECOSAR Class Organism Duration End Pt mg/L (ppm)

=========================== ================== ======== ====== ========== Hydrazines : Fish 96-hr LC50 2.386 * Hydrazines : Daphnid 48-hr LC50 9.329 * Hydrazines : Green Algae 96-hr EC50 0.676 Hydrazines : Fish ChV 0.111 ! Hydrazines : Daphnid ChV 0.566 ! Hydrazines : Green Algae ChV 0.223

Thiocarbamates, Mono : Fish 96-hr LC50 50.218 * Thiocarbamates, Mono : Daphnid 48-hr LC50 121.061 * Thiocarbamates, Mono : Green Algae 96-hr EC50 1.281 * Thiocarbamates, Mono : Fish ChV 1.987 * Thiocarbamates, Mono : Daphnid ChV 0.279 Thiocarbamates, Mono : Green Algae ChV 2.193 * Thiocarbamates, Mono : Fish (SW) 96-hr LC50 9.192 * Thiocarbamates, Mono : Mysid (SW) 96-hr LC50 8.282 *

=========================== ================== ======== ====== ========== Neutral Organic SAR : Fish 96-hr LC50 98.145 * (Baseline Toxicity) : Daphnid 48-hr LC50 58.063 * : Green Algae 96-hr EC50 54.035 * : Fish ChV 10.229 * : Daphnid ChV 6.676 * : Green Algae ChV 16.223 *

Note: * = asterisk designates: Ch emical may not be soluble enough to measure this predicted effect. If the effect level exceeds the water solubility by 10X, typically no effects at saturation (NES) NOTE: ! = exclamation designates: The toxicity value was estimated through application of acute-to-chronic ratios per methods outlined in the ECOSAR Methodology Document provided in the ECOSAR Help Menu.

### 40 CGA-300402 ECOSAR Version 1.10 Results Page SMILES : C1CCCN2C(=O)SC(N 12)=Nc3cc(c(cc3F)CL)SCC(=O)(O) CHEM : CAS Num: ChemID1: MOL FOR: C14 H13 CL1 F1 N3 O3 S2 MOL WT : 389.85 Log Kow: 2.303 (EPISuite Kowwin v1.68 Estimate) Log Kow: (User Entered) Log Kow: (PhysProp DB exp value - for comparison only) Melt Pt: (User Entered for Wat Sol estimate) Melt Pt: (deg C, PhysProp DB exp value for Wat Sol estimate) Wat Sol: 94.91 (mg/L, EPISuite WSKowwin v1.43 Estimate) Wat Sol: (User Entered) Wat Sol: (PhysProp DB exp value)

Log Kow: 2.303 (EPISuite Kowwin v1.68 Estimate) Wat Sol: 94.91 (mg/L, EPISuite WSKowwin v1.43 Estimate)

ECOSAR v1.1 Class-specific Estimations

-------------------------------------- Hydrazines-acid Thiocarbamates, Mono -acid Predicted ECOSAR Class Organism Duration End Pt mg/L (ppm)

=========================== ================== ======== ====== ========== --> Acid moeity found: Predicted values multiplied by 10

Hydrazines-acid : Fish 96-hr LC50 29.173 Hydrazines-acid : Daphnid 48-hr LC50 122.319 * Hydrazines-acid : Green Algae 96-hr EC50 8.037 Hydrazines-acid : Fish ChV 1.472 ! Hydrazines-acid : Daphnid ChV 7.844 ! Hydrazines-acid : Green Algae ChV 2.560

Thiocarbamates, Mono -acid : Fish 96-hr LC50 756.767 * Thiocarbamates, Mono -acid : Daphnid 48-hr LC50 2518.957 * Thiocarbamates, Mono -acid : Green Algae 96-hr EC50 16.597 Thiocarbamates, Mono -acid : Fish ChV 30.810 Thiocarbamates, Mono -acid : Daphnid ChV 3.833 Thiocarbamates, Mono -acid : Green Algae ChV 28.335 Thiocarbamates, Mono -acid : Fish (SW) 96-hr LC50 125.802 * Thiocarbamates, Mono -acid : Mysid (SW) 96-hr LC50 126.837 *

=========================== ================== ======== ====== ========== Neutral Organic SAR : Fish 96-hr LC50 171.254 * (Baseline Toxicity) : Daphnid 48-hr LC50 95.959 * : Green Algae 96-hr EC50 89.154 : Fish ChV 17.301 : Daphnid ChV 10.541 : Green Algae ChV 23.302

### 41 CGA-300403 ECOSAR Version 1.10 Results Page SMILES : C1CCCN2C(=O)N(C(N12)=S)c3cc(c(cc3F)CL)SCC(=O)O CHEM : CAS Num: ChemID1: MOL FOR: C14 H13 CL1 F1 N3 O3 S2 MOL WT : 389.85 Log Kow: 3.097 (EPISuite Kowwin v1.68 Estimate) Log Kow: (User Entered) Log Kow: (PhysProp DB exp value - for comparison only) Melt Pt: (User Entered for Wat Sol estimate) Melt Pt: (deg C, PhysProp DB exp value for Wat Sol estimate) Wat Sol: 8.018 (mg/L, EP ISuite WSKowwin v1.43 Estimate) Wat Sol: (User Entered) Wat Sol: (PhysProp DB exp value) Log Kow: 3.097 (EPISuite Kowwin v1.68 Estimate) Wat Sol: 8.018 (mg/L, EP ISuite WSKowwin v1.43 Estimate)

Predicted ECOSAR Class Organism Duration End Pt mg/L (ppm)

=========================== ================== ======== ====== ========== --> Acid moeity found: Predicted values multiplied by 10

Hydrazines-acid : Fish 96-hr LC50 15.145 * Hydrazines-acid : Daphnid 48-hr LC50 52.310 * Hydrazines-acid : Green Algae 96-hr EC50 4.511 Hydrazines-acid : Fish ChV 0.604 ! Hydrazines-acid : Daphnid ChV 2.878 ! Hydrazines-acid : Green Algae ChV 1.592

Thioureas -acid : Fish 96-hr LC50 598.783 * Thioureas -acid : Daphnid 48-hr LC50 19.059 * Thioureas -acid : Green Algae 96-hr EC50 7.320 Thioureas -acid : Fish ChV 95.693 *! Thioureas -acid : Daphnid ChV 0.666 ! Thioureas -acid : Green Algae ChV 1.531

Carbonyl Ureas -acid : Fish 96-hr LC50 116.750 * Carbonyl Ureas -acid : Daphnid 48-hr LC50 10.618 * Carbonyl Ureas -acid : Green Algae 96-hr EC50 0.293 Carbonyl Ureas -acid : Fish ChV 0.833 Carbonyl Ureas -acid : Daphnid ChV 1.748 Carbonyl Ureas -acid : Green Algae ChV 0.080 Carbonyl Ureas -acid : Fish (SW) 96-hr LC50 102.062 * Carbonyl Ureas -acid : Mysid (SW) 96-hr LC50 5.302 Carbonyl Ureas -acid : Fish (SW) ChV 7.129

=========================== ================== ======== ====== ========== Neutral Organic SAR : Fish 96-hr LC50 33.141 * (Baseline Toxicity) : Daphnid 48-hr LC50 21.590 * : Green Algae 96-hr EC50 20.151 * : Fish ChV 3.651 : Daphnid ChV 2.692 : Green Algae ChV 7.737

### 42 CGA-300404 ECOSAR Version 1.10 Results Page SMILES : C1CCCN2C(=O)SC(N12) =Nc3cc(c(cc3F)CL)S(CC(=O)(O))=O CHEM : CAS Num: ChemID1: MOL FOR: C14 H13 CL1 F1 N3 O4 S2 MOL WT : 405.85 Log Kow: 0.139 (EPISuite Kowwin v1.68 Estimate) Log Kow: (User Entered) Log Kow: (PhysProp DB exp value - for comparison only) Melt Pt: (User Entered for Wat Sol estimate) Melt Pt: (deg C, PhysProp DB exp value for Wat Sol estimate) Wat Sol: 260.7 (mg/L, EPISuite WSKowwin v1.43 Estimate) Wat Sol: (User Entered) Wat Sol: (PhysProp DB exp value)

Log Kow: 0.139 (EPISuite Kowwin v1.68 Estimate) Wat Sol: 260.7 (mg/L, EPISuite WSKowwin v1.43 Estimate)

Predicted ECOSAR Class Organism Duration End Pt mg/L (ppm)

=========================== ================== ======== ====== ========== --> Acid moeity found: Predicted values multiplied by 10

Hydrazines-acid : Fish 96-hr LC50 181.204 Hydrazines-acid : Daphnid 48-hr LC50 1288.383 * Hydrazines-acid : Green Algae 96-hr EC50 40.355 Hydrazines-acid : Fish ChV 17.388 ! Hydrazines-acid : Daphnid ChV 125.431 ! Hydrazines-acid : Green Algae ChV 9.718

Thiocarbamates, Mono -acid : Fish 96-hr LC50 22830.174 * Thiocarbamates, Mono -acid : Daphnid 48-hr LC50 8.7e+005 * Thiocarbamates, Mono -acid : Green Algae 96-hr EC50 159.825 Thiocarbamates, Mono -acid : Fish ChV 1154.429 * Thiocarbamates, Mono -acid : Daphnid ChV 57.415 Thiocarbamates, Mono -acid : Green Algae ChV 267.600 * Thiocarbamates, Mono -acid : Fish (SW) 96-hr LC50 1 832.747 * Thiocarbamates, Mono -acid : Mysi d (SW) 96-hr LC50 4323.208 *

=========================== ================== ======== ====== ========== Neutral Organic SAR : Fish 96-hr LC50 15646.525 * (Baseline Toxicity) : Daphnid 48-hr LC50 5815.181 * : Green Algae 96-hr EC50 5335.934 * : Fish ChV 1248.786 * : Daphnid ChV 452.261 * : Green Algae ChV 489.126 *

### 43 CGA-327066

ECOSAR Version 1.10 Results Page SMILES : C1CCCN2C(=O)N(C(=O )(N12))c3cc(c(cc3F)CL)SCC(=O)O CHEM : CAS Num: ChemID1: MOL FOR: C14 H13 CL1 F1 N3 O4 S1 MOL WT : 373.79 Log Kow: 1.843 (EPISuite Kowwin v1.68 Estimate) Log Kow: (User Entered) Log Kow: (PhysProp DB exp value - for comparison only) Melt Pt: (User Entered for Wat Sol estimate) Melt Pt: (deg C, PhysProp DB exp value for Wat Sol estimate) Wat Sol: 118.5 (mg/L, EPISuite WSKowwin v1.43 Estimate) Wat Sol: (User Entered) Wat Sol: (PhysProp DB exp value) Log Kow: 1.843 (EPISuite Kowwin v1.68 Estimate) Wat Sol: 118.5 (mg/L, EPISuite WSKowwin v1.43 Estimate)

Predicted ECOSAR Class Organism Duration End Pt mg/L (ppm)

=========================== ================== ======== ====== ========== --> Acid moeity found: Predicted values multiplied by 10

Hydrazines-acid : Fish 96-hr LC50 40.883 Hydrazines-acid : Daphnid 48-hr LC50 191.778 * Hydrazines-acid : Green Algae 96-hr EC50 10.766 Hydrazines-acid : Fish ChV 2.365 ! Hydrazines-acid : Daphnid ChV 13.439 ! Hydrazines-acid : Green Algae ChV 3.231

Carbonyl Ureas -acid : Fish 96-hr LC50 560.197 * Carbonyl Ureas -acid : Daphnid 48-hr LC50 183.078 * Carbonyl Ureas -acid : Green Algae 96-hr EC50 0.280 Carbonyl Ureas -acid : Fish ChV 4.013 Carbonyl Ureas -acid : Daphnid ChV 11.000 Carbonyl Ureas -acid : Green Algae ChV 0.076 Carbonyl Ureas -acid : Fish (SW) 96-hr LC50 489.581 * Carbonyl Ureas -acid : Mysid (SW) 96-hr LC50 248.053 * Carbonyl Ureas -acid : Fish (SW) ChV 22.093

=========================== ================== ======== ====== ==========

Neutral Organic SAR : Fish 96-hr LC50 424.930 * (Baseline Toxicity) : Daphnid 48-hr LC50 218.209 * : Green Algae 96-hr EC50 202.199 * : Fish ChV 40.831 : Daphnid ChV 22.273 : Green Algae ChV 42.300

### 44 CGA-327067 ECOSAR Version 1.10 Results Page SMILES : C1CCCN2C(=O)(N(C(=O)(N 12))c3cc(c(cc3F)CL)S(CC(=O)O)=O) CHEM : CAS Num: ChemID1: MOL FOR: C14 H13 CL1 F1 N3 O5 S1 MOL WT : 389.79 Log Kow: 1.029 (EPISuite Kowwin v1.68 Estimate) Log Kow: (User Entered) Log Kow: (PhysProp DB exp value - for comparison only) Melt Pt: (User Entered for Wat Sol estimate) Melt Pt: (deg C, PhysProp DB exp value for Wat Sol estimate) Wat Sol: 468.1 (mg/L, EPISuite WSKowwin v1.43 Estimate) Wat Sol: (User Entered) Wat Sol: (PhysProp DB exp value) Log Kow: 1.029 (EPISuite Kowwin v1.68 Estimate) Wat Sol: 468.1 (mg/L, EPISuite WSKowwin v1.43 Estimate)

Predicted ECOSAR Class Organism Duration End Pt mg/L (ppm)

=========================== ================== ======== ====== ========== --> Acid moeity found: Predicted values multiplied by 10

Hydrazines-acid : Fish 96-hr LC50 83.463 Hydrazines-acid : Daphnid 48-hr LC50 477.542 * Hydrazines-acid : Green Algae 96-hr EC50 20.288 Hydrazines-acid : Fish ChV 6.148 ! Hydrazines-acid : Daphnid ChV 39.154 ! Hydrazines-acid : Green Algae ChV 5.481

Carbonyl Ureas -acid : Fish 96-hr LC50 1661.114 * Carbonyl Ureas -acid : Daphnid 48-hr LC50 1245.111 * Carbonyl Ureas -acid : Green Algae 96-hr EC50 0.293 Carbonyl Ureas -acid : Fish ChV 11.933 Carbonyl Ureas -acid : Daphnid ChV 38.893 Carbonyl Ureas -acid : Green Algae ChV 0.080 Carbonyl Ureas -acid : Fish (SW) 96-hr LC50 1451.450 * Carbonyl Ureas -acid : Mysid (SW) 96-hr LC50 3224.395 * Carbonyl Ureas -acid : Fish (SW) ChV 49.329

=========================== ================== ======== ====== ========== Neutral Organic SAR : Fish 96-hr LC50 2384.480 * (Baseline Toxicity) : Daphnid 48-hr LC50 1049.280 * : Green Algae 96-hr EC50 967.752 * : Fish ChV 209.686 : Daphnid ChV 94.061 : Green Algae ChV 136.516

### 45 A-CFPSA ECOSAR Version 1.10 Results Page SMILES : c1(cc(c(cc1F)CL)S(CC(=O)O)=O)N CHEM : CAS Num: ChemID1: MOL FOR: C8 H7 CL1 F1 N1 O3 S1 MOL WT : 251.66 Log Kow: 0.962 (EPISuite Kowwin v1.68 Estimate) Log Kow: (User Entered) Log Kow: (PhysProp DB exp value - for comparison only) Melt Pt: (User Entered for Wat Sol estimate) Melt Pt: (deg C, PhysProp DB exp value for Wat Sol estimate) Wat Sol: 8670 (mg/L, EPISuite WSKowwin v1.43 Estimate) Wat Sol: (User Entered) Wat Sol: (PhysProp DB exp value) Log Kow: 0.962 (EPISuite Kowwin v1.68 Estimate) Wat Sol: 8670 (mg/L, EPISuite WSKowwin v1.43 Estimate)

-------------------------------------- ECOSAR v1.1 Class-specific Estimations

-------------------------------------- Anilines (Unhindered)-acid Predicted ECOSAR Class Organism Duration End Pt mg/L (ppm)

=========================== ================== ======== ====== ========== --> Acid moeity found: Predicted values multiplied by 10

Anilines (Unhindered)-acid : Fish 96-hr LC50 1895.587 Anilines (Unhindered)-acid : Fish 14-day LC50 2525.812 Anilines (Unhindered)-acid : Daphnid 48-hr LC50 18.407 Anilines (Unhindered)-acid : Green Algae 96-hr EC50 50.572 Anilines (Unhindered)-acid : Fish ChV 10.553 Anilines (Unhindered)-acid : Daphnid ChV 0.616 Anilines (Unhindered)-acid : Green Algae ChV 83.314

=========================== ================== ======== ====== ========== Neutral Organic SAR : Fish 96-hr LC50 1767.927 (Baseline Toxicity) : Daphnid 48-hr LC50 768.156 : Green Algae 96-hr EC50 708.199 : Fish ChV 154.339 : Daphnid ChV 68.129 : Green Algae ChV 96.718

### 46 APPENDIX D

SIP ANALYSIS

Table 1. Inputs Parameter Value Chemical name Fluthiacet Methyl Solubility (in water at 25 o C; mg/L) 0.8

Mammalian LD 50 (mg/kg-bw) 5000 Mammalian test species laboratory rat Body weight (g) of "other" mammalian species

Mammalian NOAEL (mg/kg-bw) 1.59 Mammalian test species laboratory rat Body weight (g) of "other" mammalian species

Avian LD 50 (mg/kg-bw) 2250 Avian test species northern bobwhite quail Body weight (g) of "other" avian species Mineau scaling factor 1.15

Mallard NOAEC (mg/kg-diet) 100 Bobwhite quail NOAEC (mg/kg-diet) 100 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. Mammalian Results Parameter Acute Chronic Upper bound exposure (mg/kg-bw) 0.1376 0.1376 Adjusted toxicity value (mg/kg-bw) 3845.8028 1.2230 Ratio of exposure to toxicity 0.0000 0.1125

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) 0.6480 0.6480 Adjusted toxicity value (mg/kg-bw) 1620.9664 4.9613 Ratio of exposure to acute toxicity 0.0004 0.1306

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

*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 exposure that has potential for effects to non-target animals.

### 47 APPENDIX E STIR Analysis Results

Input

Application and Chemical Information

Enter Chemical Name Fluthiacet methyl
Enter Chemical Use Cotton Is the Application a Spray? (enter y or n) y If Spray What Type (enter ground or air) air Enter Chemical Molecular Weight (g/mole) 403.88 Enter Chemical Vapor Pressure (mmHg) 3.31E-09 Enter Application Rate (lb a.i./acre) 0.0064

Toxicity Properties

Bird
Enter Lowest Bird Oral LD 50 (mg/kg bw) 2250 Enter Mineau Scaling Factor 1.15 Enter Tested Bird Weight (kg) 0.178
Mammal
Enter Lowest Rat Oral LD 50 (mg/kg bw) 5000
Enter Lowest Rat Inhalation LC 50 (mg/L) 5 Duration of Rat Inhalation Study (hrs) 4 Enter Rat Weight (kg) 0.35

Output Results Avian (0.020 kg ) Maximum Vapor Concentration in Air at Saturation (mg/m 3 ) 7.19E-05 Maximum 1-hour Vapor Inhalation Dose (mg/kg) 9.04E-06
Adjusted Inhalation LD 50 1.25E+01 Ratio of Vapor Dose to Adjusted Inhalation LD 50 7.21E-07 Exposure not Likely Significant Maximum Post-treatment Spray Inhalation Dose (mg/kg) 6.15E-04 Ratio of Droplet Inhalation Do se to Adjusted Inhalation LD 50 4.90E-05 Exposure not Likely Significant

Results Mammalian (0.015 kg ) Maximum Vapor Concentration in Air at Saturation (mg/m 3 ) 7.19E-05 Maximum 1-hour Vapor Inhalation Dose (mg/kg) 1.14E-05
Adjusted Inhalation LD 50 2.98E+02 Ratio of Vapor Dose to Adjusted Inhalation LD 50 3.82E-08 Exposure not Likely Significant Maximum Post-treatment Spray Inhalation Dose (mg/kg) 7.73E-04 Ratio of Droplet Inhalation Do se to Adjusted Inhalation LD 50 2.60E-06 Exposure not Likely Significant