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 

Environmental Fate 

Risk 

and 

Branch 

Effect~ 

3 

Dtvision 

U ~ 

(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 herbicide, predominantly used to control broadleaf weeds. It is a 

photobleaching imide herbicide in the 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 presence of ultraviolet light. The 

chemical structure of fluthiacet-methyl along with the chemical identifiers are provided in Table 

1. 

Table 1. Fluthiacet-methyl Chemical Identifiers 

Chemical Name Fluthiacet-methyl 

Chemical Structure 

N

N S

N

O

Cl

S

H3CO

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), and a technical formulation (279-

9550). Table 2 provides a summary of the fluthiacet-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-ethyl 

FLUTHIACETMETHYL 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 soybean. Fluthiacet-methyl usage has 

increased between 2007 and 2011 according a recent Biological 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 rate is 0.003 lb a.i./A for all crops. 

Current label application rates for fluthiacet-methyl are listed in Table 3. The application rates 

included on currently registered labels are on a per season basis. The number of applications of 

fluthiacet-methyl that can be applied 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-agricultural use sites. 

 

1

 Ratnayake, S., Haddad, Sepehr, Faulkner, J. BEAD Chemical Profile for Registration Review: Fluthiacet-methyl, 

May 28, 2013. 
4 

Table 3. Registered Fluthiacet-methyl Application Rates 

Crop/Site 

Residential 

Agricultural 

Forestry Timing; Application Type Method/ Equipment 

Maximum 

Single 

Application 

Rate by 

Formulation

(lb a.i./A) 

Maximum 

Application Rate 

Maximum 

Application 

Number 

PHI (days)b 

REI (hours)b 

MRI (days)b 

Per Year 

lb a.i./A 

Per CCa 

lb a.i./A 

Per 

Year 

Per 

CCa 

Corn 

Preplant 

Burndown; 

Postemergence 

Foliar 

Broadcast/ 

Ground 

Aerial 

0.006 NS 0.009 NS NS 30c 12d NS [3]e 

Cotton  Defoliate/ Desiccate Broadcast/ Ground Aerial 0.004 NS 0.009 NS 2 7 12d 6 Soybean 

Preplant 

Burndown, 

Emergence; 

Postemergence 

Foliar 

Broadcast/ 

Ground 

Aerial 

0.006 NS 0.009 NS NS 60 12d NS [3]e 

a. Reported as per crop cycle or per season 

b. PHI – Preharvest interval; REI – reentry interval; MRI – Minimum retreatment interval 

c. 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. 

Bold font 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 and pre-plant burndown applications for corn and soybean uses 

(May 2010). EFED evaluated these assessments for 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, potential direct risk to terrestrial 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 enhanced lighting, an interim adjustment factor 

of 29 X (EFED guidance)2will be applied to the chronic fish NOAEC. Based on this adjusted 

NOAEC, direct risk is anticipated for fish on a chronic exposure basis. There is also the potential 

for various indirect effects on non-target animal species 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 assessments 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 

Yesa

 Yesb Yesb Yesb 

Chronic No No Yesc 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 potential 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 

μg/L (ppb)

Yearly 

Concentration 

Mean μg/L (ppb)

Average of Yearly 

Concentration 

μg/L (ppb)

DP304797a Cotton 

1.0 0.19 0.14 

Tier II Groundwater 

Peak Concentration 

μg/L (ppb) 

Yearly Mean Concentration 

μg/L (ppb) 

0.08 0.08 

a. See footnote Error! Bookmark not defined.

Clean Water Act Programs 

Fluthiacet-methyl 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 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 Properties 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 volatile or to bioaccumulate. 

Table 6. Selected Physical/Chemical Parameters of Fluthiacet-methyl 

Parameter Value Source/Classification

Molecular formula C15H15ClFN3O3S2

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 KOW) 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 Properties of Fluthiacet-methyl 

As part of this problem formulation, the submitted environmental fate data were reviewed and 

fate characterization updated along with modeling input parameters in accordance with current 

guidance documents. The updated parameters will be used in future exposure assessments. 

The major routes of dissipation for fluthiacet-methyl are hydrolysis, photolysis and metabolism. 

The major route of transformation for fluthiacet-methyl is ester hydrolysis. The proposed 

fluthiacet-methyl environmental transformation scheme is presented in Figure 1. This scheme 

highlights several major fluthiacet-methyl transformation products including CGA-300402, 

CGA-300403, CGA-300404, CGA-327066, CGA-327067, and A-CFPSA. These transformation 

products are generally more stable and mobile than parent fluthiacet-methyl. Environmental fate 

parameters of fluthiacet-methyl and total toxic fluthiacet-methyl residues are presented in Table 

7 and Table 8. These parameters reflect the NAFTA 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 acid. The estimated hydrolysis half-life for 

fluthiacet-methyl at pH 9, 7, and 5 are approximately 5 hours, 19 days, and 483 days (well 

beyond the study duration), respectively. 

The combined hydrolysis half-life of fluthiacet-methyl and the corresponding free acid (CGA300402) is much longer than the study 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

H3CO

O

F

N

N S

N

O

Cl

S

HO

O

F

N

N S

N

O

Cl

S

H3CO

O

F

O

N

N S

N

O

Cl

S

HO

O

F

O

N

N N

O

Cl

S

HO

O

S F

N

N N

O

Cl

S

HO

O

O F

N

N N

O

Cl

S

HO

O

O F

O

Fluthiacet-methyl

CGA-248757

N

N N

O

Cl

S

HO

O

S F

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

O F

O ACA-CFPSA

H2N

H2N 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 Parameters of Fluthiacet-methyl 

Study 

System Name/ 

Characteristics 

Kinetic Model Fitted1

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 DT50, TIORE, or the 2nd DT50 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) Considered in Drinking Water Assessment 

Study 

System Name/ 

Characteristics 

Kinetic Model 

Fitted1 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 estimate a model input value is the calculated SFO DT50, TIORE, or the 2nd DT50 from the DFOP 

equation. 
13

Aquatic Photolysis 

Aquatic photolysis of fluthiacet-methyl was investigated in a sterile pH 5 buffered solution (acid condition 

minimizes fluthiacet-methyl hydrolysis). This study demonstrated that fluthiacet-methyl is susceptible to 

aquatic photolysis. The estimated SFO half-life is 5.7 days when transformation data for fluthiacet-methyl from 

both radiolabeled experiments are considered as part of the kinetic analysis. 

Several transformation products were observed to form as a result of photolysis; only CGA-300402 and CGA330057 were characterized quantitatively. 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 radioactivity; however, these two compounds were not identified. 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 and 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 identified as transformation products (CGA-300402, CGA-330057, 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 fluthiacet-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, ACA-CFPSA, and CGA-300404 were shown to be fairly persistent as little 

concentration decline was observed by the end of the study. The remaining degradates (CGA-300402, CGA330057, CGA-300403, CGA-327066, A-CFPSA) showed formation and decline within the study duration (360 

days). The only major degradates were CGA-300402, CGA-300403, CGA-327067, CGA-327066, and ACFPSA. The last two were only observed in the phenyl-labeled study (MRID 43348452). The remaining 

degradates were minor degradates 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 maximum 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 first-order in parallel (DFOP) kinetic models were 

115 and 1030 days, respectively. These results reflect the stability of some 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 condition following an initial aerobic phase. 
14

Several transformation products (CGA-300402, CGA-330057, CGA-300403, 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 studies. The combined aerobic soil metabolism half-life of 

the toxic fluthiacet-methyl residues estimated using non-linear SFO and DFOP kinetic 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 most mobile of the fluthiacet-methyl transformation products is CGA-327067 

which is considered mobile. Additional batch equilibrium data are available for CGA-300404, CGA-327066, 

and CGA-330057, which indicate that all of these transformation products are more mobile than the fluthiacetmethyl. 

Field Dissipation 

Field dissipation data are consistent with the results reported in the laboratory studies. Fluthiacet-methyl 

transforms quickly to several transformation products that are more persistent and mobile than fluthiacetmethyl. 

Bioconcentration 

Fluthiacet-methyl was unstable under the test conditions; however, it does not appear to accumulate. Numerous 

structurally similar transformation products including CGA-300402, CGA-300403, CGA-300404, CGA327066, and CGA-327067 were identified and quantified in fish tissues. A bioconcentration factor (BCF) for 

parent only was not calculated: however, 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 transformation products were reported in the submitted 

environmental fate studies. These transformation products are listed in APPENDIX B with the maximum 

amounts of each observed in the various environmental fate studies. In the aqueous photolysis study submitted 

to EPA, there is a large amount of the 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 terrestrial taxonomic groups, respectively, and the most 

sensitive surrogate species tested to characterize the potential acute and chronic ecological effects 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 ecotoxicity information, the organisms facing 

the greatest hazard are fish and aquatic and terrestrial plants. No toxicity data were submitted or identified in the 

open literature for the fluthiacet-methyl transformation products. 

Fluthiacet-methyl is a light dependant peroxidizing herbicide (LDPH). LDPHs are a unique class of chemicals 

that can be more toxic in the presence of ultraviolet light. In the absence 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 supplying data for a chemical specific 

LDPH adjustment factor. While enhanced toxicity in the presence of uV light is not necessarily limited to 

aquatic fish and could be observed in other taxa such as aquatic invertebrates, birds, mammals and plants6, at 

this time, the EPA is only applying an adjustment factor to fish. Data on the effects of enhanced lighting 

(compared to standard laboratory/greenhouse lighting) for other taxa would reduce the uncertainty in the 

assessment. 

Table 9. Summary of the Most Sensitive Endpoints from 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 fisha

Acute 

Rainbow Trout 

(Oncorhynchus 

mykiss) 

TGAI 

LC50 = 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 

LC50 = 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 

EC50 = >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 on 

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 

EC50 = 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 

subcapitatab

)

TGAI 

EC50 = 2.51 μg a.i./L 

NOAEC = 0.40 μg

a.i./L

Endpoint: cell density 

43348443 

Acceptable -- 

Vascular 

Duckweed 

(Lemna gibba) 

TGAI 

EC50 = 1.4 μg a.i./L 

NOAEC = 0.065 μg 

a.i./Lc

Endpoint: number of 

fronds 

43348441 

Acceptable -- 

a. Freshwater fish represent surrogates for aquatic-phase amphibians.

b. Formerly Selenastrum capricornutum 

c. Negative control was compared with the test concentration in recalculated EC50 and NOAEC with NUTHATCH 

continuous endpoint statistical analysis. Previous EC50 and NOAEC calculations were done with probit 

regression analysis (with solvent control compared to test concentrations). 

NC= Not calculated because neither moving 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) 

LD50 >5000 mg/kg bw 

No mortality at any dosage 

43348411 

(Acceptable) 

Practically nontoxicc

Acute 

Inhalation 

Laboratory rat 

(Rattus norvegicus) LD50 > 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 

Birdsa

Acute Oral 

Bobwhite quail 

Mallard 

(Colinus virginianus) 

(Anas platyrhynchos)

LD50 >2250 mg/kg bw 

No mortality at any dosage 

43348405 

43348406 

(Acceptable) 

Practically nontoxicc

Subacute 

Dietary 

Bobwhite quail 

Mallard 

(Colinus virginianus) 

(Anas platyrhynchos)

LC50 >5620 mg/kg-diet 

43348407 

43348408 

(Acceptable) 

Practically nontoxicc

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 

ppm, 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) LD50 > 100 μg/bee 

No mortality at any dosage 

43348445 

(Acceptable) 

Practically nontoxicb

Terrestrial 

Plants 

Vegetative 

Vigor 

Dicot-Tomato 

NOAEC: 0.000074 lb a.i./A 

45376305 

45376304 -- 
18

(TEPd + 

Adjuvant) 

EC25: = 0.00017 lb a.i./A 

Endpoint: Shoot weight 

(Acceptable) 

Monocot-Onion NOAEC: 0.002 lb a.i./A 

EC25: 0.0062 lb ai/A 

Endpoint: Shoot weight 

Seedling 

Emergence 

(TGAI) 

Dicot-Tomato NOAEC: 0.006 lb a.i./A 

EC25: >0.018 lb a.i./A 

Endpoint: Phytotoxicitye 43348438 

(Acceptable) -- 

Monocot-Onion

NOAEC: 0.006 lb a.i./A 

EC25: 0.010 lb a.i./A 

Endpoint: Dry weight 

a. Birds represent surrogates for terrestrial-phase amphibians and reptiles. 

b. Based on acute contact LD50 (μg a.i./bee) <2 highly toxic; 2-10.99 moderately toxic; ≥11 practically non-toxic 

c. Acute Oral (avian/mammal): Based on LD50 (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), herbicidal efficacy screening data were submitted. 

While the data generally suggest that CGA-327067 is less toxic than the parent compound and CGA-300402 

has approximately equivalent toxicity 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 percent 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 the 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 transformation 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 waters through spray drift and penetration of the canopy during application 

and foliar wash-off to the soil, followed by runoff of fluthiacet-methyl sorbed soil or dissolved phase fluthiacetmethyl. Fluthiacet-methyl may also leach to groundwater. Field dissipation studies show that fluthiacet-methyl 

transforms very quickly in the environment—this reduces the likelihood that fluthiacet-methyl will contaminate 

 

7 PPDB. Pesticide Properties Database. University of Hertfordshire. http://sitem.herts.ac.uk/aeru/footprint/index2.htm
19

surface water or groundwater. However, in contrast, aerobic 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 surface water, as well as leach to groundwater. 

The exposure pathways for fluthiacet-methyl and its transformation products may result in a wide range of 

potential aquatic and terrestrial exposure scenarios. For this problem formulation, the drinking water and 

inhalation 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. However, it is 

noted that the screening analysis do not include aggregation with all other exposure pathways (dietary, dermal, 

inhalation, or drinking water), which together, may contribute to a total exposure 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 identified as potentially important, and the degree of certainty associated with 

screening-level risk assessment conclusions. SIP and STIR are described in detail at 

http://www.epa.gov/oppefed1/models/terrestrial/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 updated 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 toxicological concern in surface 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 the 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 consultation with the ROCKS. The registration 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 environmental fate study (hydrolysis, aqueous photolysis, 

aerobic soil metabolism, etc.) will be used to calculate the amount of total toxic residues present in each study at 

each sampling interval. If a transformation product was not identified in one of the studies it will be assumed to 

be a toxic residue. The total concentrations at each sampling interval will be used to recalculate the rate constant 

and the corresponding half-life value for each study. These data 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 parent value. If data are available for both fluthiacet-methyl and the 

transformation products of toxicological 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 the assessment. If a residue or concern is identified to have a different 

mode of toxicity or is substantially more toxic than the parent it will be modeled separately if data are available. 

The current models available for conducting drinking water assessment for surface 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 application 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 version 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 best fit through 13 singleapplication groundwater studies. PRZM-GW can be used to simulate vertical pesticide transport through the soil 

profile into an aquifer following application to an agricultural field. The PRZM scenarios used in groundwater 

simulations are representative of vulnerable sites—shallow unconfined aquifers under an agricultural field with 

leaching prone soil—and output values represent pesticide 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 bound values on the concentrations of toxic residues that might be found in 

drinking water supplied by groundwater. 

Ecological Risk Assessment 

Stressors of Concern 

In order to address the risk hypothesis, the potential for adverse effects on the environment will be estimated. 

The use profile, environmental fate, and ecological effects 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 structural characteristics that are indicative of LDPH chemicals (as defined in 

the interim guidance memo—U.S. EPA, 2010). Therefore, in the absence of toxicity data suggesting these 

transformation products are more or less toxic than the parent, the transformation products will be assumed to 

be as toxic as the parent and a total toxic residues (TTR) approach (FIFRA SAP, 2008)8 will be used to assess 

risk for terrestrial and aquatic exposure analysis. 

Risk quotients (RQs) will be derived for total toxic residues (fluthiacet-methyl and the transformation products 

listed above) by dividing estimated environmental concentrations (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 indicated 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 environmental concentrations of total toxic fluthiacet-methyl 

residues will be used to calculate risk quotients. For the T-REX model, we will assume that the default half-life 

value of 35 days for foliar residue dissipation will capture the parent and degradates, 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 Characteristics. http://www.epa.gov/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 biological 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 and potential chemical mixture toxicity data for aquatic 

life, terrestrial plants, and wildlife. ECOTOX was created 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 integration of exposure and ecological effects to determine the potential ecological 

risk from the use of pesticides and the likelihood of direct and indirect effects to non-target organisms in aquatic 

and terrestrial habitats. For the assessment of risks, the risk quotient (RQ) method is used to compare exposure 

and measured toxicity values. EECs are divided by acute and chronic toxicity values. 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 potential to cause adverse direct or indirect 

effects to non-target organisms. In addition, 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 federally-listed threatened and/or endangered (listed) species from registered 

uses of pesticides in registration review. 

Endocrine Disruptor Screening Program 

Fluthiacet-methyl is not included in the first group of 67 chemicals issued an order to conduct Tier 1 EDSP 

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

6. PRELIMINARY IDENTIFICATION 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 are needed in order to support the registration review exposure assessments. 

Rationale for the additional data requested is also presented. 
22

Table 11. Submitted Environmental Fate Data 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 TTR 

concentrations 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 TTR 

concentrations 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 TTR 

concentrations 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 whether or not further data 

are needed in order to support risk assessment. Rationale for the additional data requested is presented below 

the tables. 

Table 12. Submitted Aquatic Ecological 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 toxicity 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 classified 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 specific LDPH adjustment 

factor. 

850.1500 Fish life cycle No Data No 

850.4400 Aquatic plant 

growth: 

Tier II vascular 

plants 

43348441 Acceptable 

45376306 No 

(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 LD50

(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 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. 

124-1 Terrestrial Plant 

Field Testing No data No 

124-2 Aquatic Plant 

Field Testing No data No 

Additional effects information that would be useful to the Agency include: 

1. ecological incidents (non-target plant damage and 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 (irradiated 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 (irradiated 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-methyl 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-1H- [1.2,4 ]triazolo[1,2-

a] pyridazin- 

(3H)-yl)phenylthio] acetic acid 

Formula: C14H13ClFN3O3S2

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

H3CO

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: C15H15ClFN3O4S2

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

HO

O

S F

[[2-chloro-4-fl uoro-5-( 

tetrahydro- 6-hydroxy-3-oxo-1-

thiooxo-1H- [1.2,4) triazolo[1,2-

a] pyridazin-(3H)-

phenyl]sulfinyl] acetic acida 

Formula: C14H13ClFN3O3S2

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: C14H13ClFN3O4S2

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

HO

O

O F

[[2-chloro-4-fluoro-5-( 

tetrahydro-1 ,3-dioxo-1H-[1,2,4] 

triazolo[[ 1,2-a ]pyridazin2(3H)-yl) phenyl]thio]acetic acid 

Formula: C14H13ClFN3O4S 

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

HO

O

S F

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: C14H13ClFN3O4S2

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-327067 

DeS-FA-SO2602 

N

N

N

O

Cl

S

HO

O

O F

O

[[2-chloro-4-fluoro-5-

(tetrahydro-6-hydroxy-3-oxo-1-

thiooxo-1H-[1,2,4] triazolo[1,2-

a] pyridazin-(3H)-

phenyl]sulfinyl] acetic acid 

Formula: C14H13ClFN3O5S 

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 26.96b

 

(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 

H2N Cl

S

HO

O

F

O

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

Formula: C8H7ClFNO3S 

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

HO

O

O F

O

H2N

 

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

Formula: C9H8ClFN2O4S 

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 rearrangement of the thiadiazolo pyridazin ring. It is not a sulfinyl (sulfoxide), because the thioether link between 

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, EPISuite 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: Chemical 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(N12)=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, EPISuite 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, 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 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 : Mysid (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)(N12))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 25oC; mg/L) 0.8 

 

Mammalian LD50 (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 LD50 (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 LD50 (mg/kg bw) 2250 

Enter Mineau Scaling Factor 1.15 

Enter Tested Bird Weight (kg) 0.178 

Mammal 

Enter Lowest Rat Oral LD50 (mg/kg bw) 5000 

Enter Lowest Rat Inhalation LC50 (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/m3

) 7.19E-05 

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 9.04E-06 

Adjusted Inhalation LD50 1.25E+01 

Ratio of Vapor Dose to Adjusted Inhalation LD50 7.21E-07 Exposure not Likely Significant 

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 6.15E-04 

Ratio of Droplet Inhalation Dose to Adjusted Inhalation 

LD50 4.90E-05 Exposure not Likely Significant 

 

Results Mammalian (0.015 kg ) 

Maximum Vapor Concentration in Air at Saturation 

(mg/m3

) 7.19E-05 

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 1.14E-05 

Adjusted Inhalation LD50 2.98E+02 

Ratio of Vapor Dose to Adjusted Inhalation LD50 3.82E-08 Exposure not Likely Significant 

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 7.73E-04 

Ratio of Droplet Inhalation Dose to Adjusted Inhalation 

LD50 2.60E-06 Exposure not Likely Significant