## 2 Listed Plant Taxon Potential Direct Effects

Terrestrial and semi

- aquatic

plants

– monocots Yes (Grass es )

- All uses of clethodim; e ffects 16 to >997 feet from the edge of the field

Terrestrial and semi

- aquatic

plants

– dicots No effects

Aquatic plants No effect s

Listed Animal Taxon Potential Direct Effects

Acute Notes Chronic Notes

Terrestrial invertebrates No effect s N o effects

Mammals Yes Uses with a total annual app. rate >

2.0 lb a.i./A (only) Yes

(dose

- basis) U ses with total annual app. rate > 1.25 lb a.i./A

(only) ; however, no reproductive effects were

noted in the study.

Birds No effect s No effect s

Reptiles No effects No effect s

Amphibians

(terrestrial

- phase) No effect s No effect s

F ish 1 

## No effect s Yes All uses of clethodim

Amphibians (aquatic

- phase) No effect s Yes All uses of clethodim

Aquatic Invertebrates 2 

## No effect s No effect s

1 

### Due to the lack of chronic toxicity data, f reshwater fish data was used as a proxy representation to estimate effects to estuarine/marine fish

2 

### Due to the lack of chronic toxicity data, freshwater invertebrate data was used as a proxy representation to estimate effects to estuarine/marine inverte brates

## 3 Based on this preliminary asse ssment, there is the potential of effect s to listed and non

- listed

monocot plants , specifically grasses (family Poaceae), from exposure to clethodim residues of

concern at all application rates . There is also potential of effect s to fish (surrogates for aquatic

phase amphibians) from chronic exposure to clethodim residues of concern at all application

rates

. There is also the potential of effects to mammals from acute and chronic exposure to

clethodim re sidues of concern for a variety of uses. Listed species of terrestrial and aquatic

plants and animals may also be affected through indirect effects because of the potential for

direct effects on listed and non

- listed monocot plant species , specifically those species that rely

on grasses

. Potential direct effects on mammals, terrestrial monocot plants

, and fish (surrogates

for aquatic

- phase amphibians) from the use of clethodim may be associated with modification of

primary constituent elements of design ated critical habitats, where such designations have been

made. However, a t this current stage of the Registration Review process, it is premature to make

effects determinations for listed species until further refinements are conducted. In order to

make effects determinations for individual species, useful refinements may include analyses of

1) more detailed, species

- specific ecological and biological data; 2) more detailed and accurate

information on clethodim use patterns; and 3) sub

- county level spati al proximity data for the co

occurrence of potential effects areas and listed species and any designated critical habitat.

Examples of such refinements are described below.

EFED is currently developing tools that are expected to further refine the assessment and are

designed to support effects determinations for individual federally listed species and their

designated critical habitats (where applicable). Scientific information obtained from the U.S.

Fish & Wildlife Service (USFWS), the National Ma rine Fisheries Service (NMFS), and other

reliable sources is being collated by EFED to address all currently listed species. The

information will be stored in an Office of Pesticide Programs Pesticide Registration Information

SysteM (PRISM) knowledgebase. The listed species knowledgebase will consist of an

information repository that houses biological and behavioral information relevant to individual

species ( e.g. , habitat, diet, and life history, including specific temporal and spatial associations)

and a document repository that contains supporting documents ( e.g ., USFWS recovery plans)

and electronic information ( e.g ., GIS data files). For terrestrial taxa, the biological information

relevant to risk quotient (RQ) calculations ( e.g ., diet and body weigh t) will be used to

parameterize exposure estimates to derive species

- specific RQs using a method consistent with

currently used methods in the T

- REX model.

Refinements may also include more detailed analyses of the registered uses and their use patterns

that result in LOC exceedances for federally listed species in the screening

- level assessment.

The analyses may include more information on where, when, and how clethodim is used on

crops including: fa llow land, golf course turf, non

- cropped areas , alfal fa, o rnamentals,

landscape d areas, non

- bearing food crops , around buildings, bare soil, mulched areas , g rass

forage/fodder/hay , c lover , herbs, turnip greens, mustard, vegetables, radishes, mint, sod farms,

be ets, brassica vegetables, carrots, cranberries, cucurbit vegetables, fruiting vegetables, leafy

vegetables, strawberries , d ried beans, Christmas trees, cotton, forest trees, peanuts, potatoes, root

and tuber vegetables, sainfoin, soybeans, sugar beets, sunflowers, sweet potatoes, tomatoes,

trefoil, yams , lentils, garlic, onions, tree fruits, tree nuts, asparagus, hops, safflower, sesame

, sage, shallots, artichokes, bushberries including cranberries, caneberries, peaches , flax,

meadowfoam, seeds, kenaf, canola, wildlife food plots, succulent beans, legume vegetables,

## 4 dried and succulent peas, and corn ( field)

. Actual usage data (when available) and national land

cover datasets that indicate potential use sites ( e.g ., national land cover dataset (NLCD), crop

data layer (CDL)) may be used to support a more refined analysis of where clethodim is

reasonably expected to be used. Similarly, refinements for the timing of applications and how

clethodim is used may be based on the analysis of additional usage data, beyond what were

available at the time of the scr eening

- level assessment, and a more in

- depth exploration of

agronomic practices.

A committee of the National Research Council (NRC) has provided advice on ecological risk

assessment tools and scientific approaches under ESA and FIFRA (Project Identifica tion

Number DELS

- BEST

- 11

- 01). Specific recommendations relate to the use of “best available

data ; ” methods for evaluating sublethal, indirect, and cumulative effects; the state of the science

regarding assessment of mixtures and pesticide inert ingredient s; the development, application,

and interpretation of results from predictive models; uncertainty factors; and what constitutes

authoritative geospatial and temporal information for the assessment of individual species

, habitat effects and probabilistic r isk assessment methods

. The EPA, NOAA, FWS and USDA

are currently working to develop a plan on how to address these recommendations

.

The refinements based on individual species data; additional, detailed usage information, when

available; and further rec ommendations from the NRC report are expected to help to more

accurately identify potential areas of effect and to better inform effects and habitat

determinations for listed species and any designated critical habitats. For example, if clethodim

is used when a particular species of concern is not present ( e.g ., it is migratory) or is not co

located in space, then risk of potential direct effects to the species may often be precluded. If

LOCs are still exceeded for fish (surrogate for aquatic

- phase amphibians), mammals, and

terrestrial monocot plants after conducting the refined analyses, further analyses of the potential

spatial and temporal co

- occurrence of listed species of concern (and any designated critical

hab itat) may be conducted. The extent of possible refinement in the analyses of spatial/temporal

co

- occurrence will largely depend on the scale and quality of the available sub

- county level use

site ( e.g ., N ational L and C over D ataset , C ropland D ata L ayer ) an d species location data

.

Mitigations: If registrant

- proposed annual application rate limits of 0.5

- 1.0 lb a.i./A are provided

on the labels, it may reduce exposure in the environment. For example, when RQ values were

estimated based on conservative assu mptions, (i.e., 7

- day interval), there were no RQ values that

exceeded the LOC (acute or chronic) when the annual application rate was 1.0 lb a.i./A.

Therefore, this reduction would reduce the potential for effects to listed and non

- listed mammals

based o n acute and /or c hronic exposure of clethodim.

Regardless of any changes to the proposed application rates there would not be a reduction in the

potential for effects to fish (surrogate for aquatic

- phase amphibians) on a chr o nic exposure basis

or effect s to terrestrial monocot plant species, especially grass species sufficient to bring RQs to

below concern levels

. For fish

, the only available chronic fish toxicity study did not measure the

typical sublethal (growth or reproduction) endpoints for fi sh. T he only endpoint that was

measured was survival; and therefore, the NOAEC could potentially be an underestimation of

risk to fish , and actual endpoint could potentially be even lower

. E ffects to terrestrial monocot

plant species , especially grass species would s till be of concern at great distances from the edge

## 5 of the field (16 to >997 feet from the edge of the field)

. However, the distance from the edge of

the field where effects to listed monocot plants could be decreased with increased spray droplet

size (medium

- coarse to coarse

- very coarse) and a decreased boom height (high to low) for aerial

and ground applications, respectively ( e.g., aerial app. rate 0.1 25 lb a.i./A

, medium

- coarse to

coarse

- very coarse, distance decreased from >997feet to 955 feet ; ground app. rate 0.25 lb a.i./A

, high to low boom hight, distance decreased from 525 feet to 367 feet )

.

## 6 

# Ecological Risk Assessment for the Registration Review of

Clethodim



# S O H O

N O Cl

(5 RS )

- 2

- {(1 EZ )

- 1

- [(2 E )

- 3

- chloroallyloxyimino]propyl}

- 5

- [(2 RS )

- 2

- (ethylthio)propyl]

- 3

- hydroxycyclohex

- 2

- en

- 1

- one

CAS No.: 99129

- 21

- 2

PC Code: 121011

Prepared by:

Christina Wendel, Biologist

Greg Orrick, Environmental Scientist

Reviewed by:

R. David Jones , Ph.D., Senior Agronomist

Kristina Garber, M.S. Senior Biologist

Jean Holmes, DVM, MPH, Risk Assessment Process Leader

Approved by:

Brian Anderson

, MEM, Branch Chief

Environmental Risk Branch II

Environmental Fate and Effects Division

Office of Pesticide Programs

U.S. Environmental Protection Agency

1200 Pennsylvania Avenue, NW

Washington, D.C. 20460

January 13, 2014

## 7 

# Table of Contents

1. EXECUTIVE SUMMARY

................................ ................................ .................... 9

1.1. Purpose of Assessment

................................ ................................ ........................... 9

1.2. R isk Conclusions

................................ ................................ ................................ .... 9

1.3. Environmental Fate Summary

................................ ................................ ................ 9

1.4. Effects Summary

................................ ................................ ................................ ..... 9

1.5. Main Uncertainties

................................ ................................ ................................ 10

2. PROBLEM FORMULATION

................................ ................................ .............. 11

2.1. Nature of the Stressor

................................ ................................ ............................ 11

2.2. Usage Update

................................ ................................ ................................ ........ 12

3. ANALYSIS

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

3.1. Use Characterization

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

3.2. Environmental Fate Characterization

................................ ................................ ... 16

3.3. Exposure Characterization

................................ ................................ .................... 24

3.3.1. Aquatic Exposure

................................ ................................ ................................ .. 24

3.3.1.1. Bioaccumulation

................................ ................................ ....................... 27

3.3.1.2. Monitoring Data

................................ ................................ ........................ 27

3.3.2. Terrestrial Exposure

................................ ................................ .............................. 27

3.3.2.1. Dietary Modeling

................................ ................................ ...................... 27

3.3.2.2. Inhalation Modeling

................................ ................................ .................. 33

3.3.2.3. Drinking Water Modeling

................................ ................................ ......... 33

3.3.2.4. Plants Modeling

................................ ................................ ........................ 33

3.4. Ecological Effects Characterization

................................ ................................ ...... 34

3.4.1. Aquatic Animals

................................ ................................ ................................ ... 35

3.4.1.1. F ish

................................ ................................ ................................ ............ 36

3.4.1.2. Aquatic Invertebrates

................................ ................................ ................ 37

3.4.2. Aquatic Plants

................................ ................................ ................................ ....... 38

3.4.2.1. Non

- Vascular Plants

................................ ................................ ................. 38

3.4.2.2. Vascular Plants

................................ ................................ .......................... 39

3.4.3. Terrestrial Animals

................................ ................................ ............................... 39

3.4.3.1. Birds

................................ ................................ ................................ .......... 40

3.4.3.2. Mammals

................................ ................................ ................................ ... 40

3.4.3.3. Terrestrial Invertebrates

................................ ................................ ............ 41

3.4.4. Terrestrial Plants

................................ ................................ ................................ ... 41

3.4.4.1. Dicotyledon plants

................................ ................................ .................... 42

3.4.4. 2. Monocotyledon plants

................................ ................................ ............... 42

3.4.5. Degradate Toxicity Data

................................ ................................ ....................... 42

3.4.6. Endocrine Disruptor Screening Program

................................ .............................. 42

3.5. Review of Incident Data

................................ ................................ ....................... 43

4. RISK ESTIMATION

................................ ................................ ............................ 44

4.1. Non

- target Aquatic Organisms

................................ ................................ ............. 44

4.2. Non

- target Terrestrial Organisms

................................ ................................ ......... 45

4.2.1. Terrestrial Animals

................................ ................................ ............................... 45

4.2.2. Birds

................................ ................................ ................................ ...................... 46

4.2.3. Mammals

................................ ................................ ................................ ............... 46

## 8 4.3. Terrestrial I nvertebrates

................................ ................................ ........................ 50

4.4. Non

- target Terrestrial and Semi

- aquatic Plants

................................ .................... 50

5. RISK DESCRIPTION

................................ ................................ .......................... 51

5.1. Risks to Aquatic Organisms

................................ ................................ .................. 51

5. 1.1. Fish (surrogates for aquatic

- phase amphibians)

................................ ................... 51

5.1.2. Aquatic Invertebrates

................................ ................................ ............................ 53

5.1.3. Aquatic Plants

................................ ................................ ................................ ....... 53

5.2. Risks t o Terrestrial Organisms

................................ ................................ .............. 53

5.2.1. Terrestrial Animals

................................ ................................ ............................... 53

5.2.2. Terrestrial Plants

................................ ................................ ................................ ... 60

5.3. Probit Slope Response Analysis of LOC Values and Acute RQ Values

.............. 62

5.4. Re

- evaluation of the Risk Hypothesis

................................ ................................ ... 64

6. REFERENCES

................................ ................................ ................................ ..... 64

6.1. Ecotoxicity Studies

................................ ................................ ............................... 65

6.2. Env ironmental Fate and Product Chemistry Studies

................................ ............ 69

APPENDIX A. Aquatic Model Input/Output Files

................................ ................................ ..... 71

APPENDIX B. Sample T

- REX, and TerrPlant Inputs/Outputs for Clethodim

........................... 72

APPENDIX C. Summary of Toxicity Endpoints and Study Classifications for Clethodim

....... 76

APPENDIX D. Clethodim Incidents

................................ ................................ ........................... 82

APPENDIX E. STIR and SIP Inputs and Outputs

................................ ................................ ....... 85

APPENDIX F. Summary of AgDrift Terrestrial Outputs for Clethodim

................................ .... 87

APPENDIX G. ECOTOX Summary Tables and Accepted Papers

................................ ........... 103

APPENDIX H. ECOTOX Open Literature That Passed Initial Screen

................................ ..... 114

## 9 1. EXECUTIVE SUMMARY

1.1. Purpose of Assessment

The purpose of this assessment is to evaluate the potential risks of c lethodim ’s registered uses on

non

- target organisms, including federally listed endangered and threatened (listed) species. This

risk assessment incorporates the available ex posure and effects data, and most current modeling

and risk methodologies, some of which were not available at the time previous clethodim r isk

assessments were conducted

. This assessment is based on the problem formulation document for

registration revie w (USEPA, 2008). The problem formulation is cited for information that

remains current, while information that is new or updated is presented in this assessment.

1.2. Risk Conclusions

The re is the potential for chronic direct effects to fish for all uses of clethodim . There are

potential effects to listed and non

- listed monocot plants

, specifically grass species (family

Poaceae)

, for all uses of clethodim . There is the potential for acute and chronic direct effects to

mammals for uses of clethodim with a to tal annual application rate greater than 2.0 lb a.i./A, and

1.25 lb a.i./A, respectively.

Risk to other taxonomic groups did not exceed concern levels.

1.3. Environmental Fate Summary

Clethodim is microbially oxidized to moderately persistent sulfoxide and sulfone degradates

within days of application. Clethodim is soluble in water up to 29 mg/L and will not appreciably

volatilize or bioconcentrate in fish. The compound and its sulfoxide and sulfone degradates are

mobile in soil and may be transported to surface and ground waters. Identified compounds

containing the cyclohexenone ring and organosulfur side chain are considered the residues of

concern (ROC) for this assessment because the toxic moiety of the active ingredient appears to

potentially be i ntact. Exposure to the residues of concern is estimated using the Total Residue

(TR) modeling method.

1.4. Effects Summary

Clethodim generally has low acute toxicity, but does cause toxicity on a chronic basis at

relatively low exposure levels to aquatic organisms, particularly to fish.

Clethodim is slightly to practically non

- toxic to freshwater fish, practically non

- toxic to

estuarine/marine fish, and moderately to slightly toxic to freshwater and estuarine/marine

invertebrates on an acute exposure basis; practically non

- toxic to avian species on an acute oral

and acute dietary exposure basis; slightly toxic to mammalian s pecies on an acute oral

- exposure

basis ; and practically non

- toxic to terrestrial invertebrates (contact) on an acute exposure basis.

Chronic exposure resulted in reduced survival for freshwater fish (fathead minnows)

, but effects

on reproduction were not m easured, (NOAEC = 0.01 mg a.i./L ; LOAEC = 0.31 mg a.i./L );

however, the rainbow trout was more sensitive on an acute exposure basis, and so an acute to

chronic ratio (ACR) to estimate a NOAEC value for rainbow trout was completed (estimated

## 10 NOAEC = 0.002 m g a.i./L for rainbow trout) . Chronic exposure resulted in r educed

reproduction and survival to freshwater invertebrates ( Daphnia magna ) (NOAEC = 0.93 mg

a.i./L ; LOAEC = 3.0 mg a.i./L ). Acute and chronic toxicity data are not available for

estuarine/marin e fish or invertebrates; therefore the estimated freshwater fish and aquatic

invertebrate NOAEC values for rainbow trout and daphnids were used as a proxy for e stimating

potential toxicity to estuarine/marine fish and invertebrates, respectively. While th ese values

could be protective based on comparisons of the toxicity on an acute exposure basis, there are

also major uncertainties , especially with the chronic fish endpoint, which is detailed below.

Chronic exposure in birds resulted in no effects under the conditions of the submitted studies

(NOAEC = 833 mg a.i./kg

- diet ) , and chronic exposure in mammals resulted in decreased

parental weight and food consumption in both generations , but no reproductive effects were

observed (NOAEC = 500 ppm; 51 mg a.i./kg

- bw ; LOAEC = 1500 ppm; 263 mg a.i./kg

- bw ).

No effects were observed for terrestrial dicot plants. Effects to monocot plants were observed in

corn, ryegrass, and oat; but not onion

. The lowest EC 25 

## value was 0.003 lbs a.i./ a cre. Therefore,

given the mode of action of clethodim ( inhibiting the acetyl

- coenzyme A carboxylase (ACCase)

enzyme of grass species ), the target species of clethodim

. T he results observed in the toxicity

tests for monocot plant species for clethodim, the ris k to terrestrial plants can be refined and

limited to a narrower portion of monocot plants , grass species . The non

- target terrestrial plant

species of concern from clethodim application are within the grass ( Poaceae ) family.

1.5. Main Uncertainties

T here are uncertainties with the chronic fish endpoint that is used in this risk assessment. First,

the available fathead minnow toxicity study NOAEC endpoint is based on mortality, and not the

typical sublethal (growth or reproduction) endpoints that are used for evaluating chronic

exposures . Therefore, there could be an underestimation of risk to fish on a chronic exposure

basis

.

There are no eco toxicity data for any of the degradates of clethodim . T herefore, t he toxicities of

the degradates of concern are uncertain. For the purpose of this assessment, degradates

containing the cyclo hexenone ring and organosulfur side chain ( clethodim sulfoxide, clethodim

sulfone, clethodim oxazole, clethodim oxazole sulfoxide, clethodim oxazole sulfone, clethodim

imine, c lethodim imine sulfoxide, and clethodim trione sulfoxide ) are assumed to have the same

toxicity as the parent compound (USEPA, 2008) because the toxic moiety of the active

ingredient appears to potentially be intact . However, i f the degradates of concern were shown to

be much less toxic than clethodim, then exposure estimates (for clethodim alone) in this

assessment would be 4

- 13x lower

. For example, if a study was to show that clethodim sulfoxide

is much less toxic than clethodim to fish on a chronic exp osure basis, then clethodim would have

no degradates of concern for fish because the sulfoxide is the degradate most structurally similar

to clethodim and all other degradates could be assumed less toxic than clethodim if the sulfoxide

is. In the absence of such data or if submitted data confirm the assumption, the degradates of

concern are assumed no more or less toxic than clethodim.

The total residue ( TR ) modeling approach involves some uncertainty, since the soil mobility of

one mobile compound and th e product chemistry values of the parent compound are used to

## 11 represent all of the residues of concern. Also, the degradation kinetics of the residues of concern

may not be first

- order. The soil mobility of clethodim sulfoxide is used to represent the re sidues

of concern b ecause up to 75% of clethodim oxidizes to its sulfoxide (in soil, 3

- 7 days after

application)

, making the sulfoxide the most prominent degradate of concern. C lethodim

sulfoxide is more mobile in soil than clethodim and its oxazole sulfo xide, but less mobile in soil

than clethodim sulfone. T herefore, use of its soil mobility to represent the residues of concern in

modeling may be representative and may be conservative, but i s not a worst case assumption.

Conservative assumptions were made for environmental fate inputs for aquatic exposure

modeling i n the absence of data. Without an aerobic aquatic metabolism study , clethodim

residues of concern in modeled aerobic aquatic systems were assumed to degrade at half the rate

as that in aero bic soil. The single available anaerobic aquatic metabolism half

- life was

multiplied by three for exposure modeling to account for potential variability. Only two aerobic

soil metabolism half

- lives were available to gen erate model inputs , both for sandy loam soils

from Greenville, Mississippi.

It is uncertain whether maximum use patterns may be implemented due to changing market

forces or weed pressures. If labeled annual application rates we re an order of magnitude lower

than those assumed in this as sessment ( e.g. , 0.5 versus 4.5 lbs a.i./A), then exposure estimates for

the lower rates would b e an order of magnitude lower as well. In addition, for the terrestrial

exposure analysis, a 7 day interval between applications was used for modeling the conse rvative

assumptions associated with lack of label language. Therefore, based on this assumption for the

terrestrial exposure analysis new crop cycles would be occurring every two weeks; however, that

is likely not a realistic representation of field pract ices. Therefore, if additional information was

provided for annual application limits, a more refined analysis could be completed, and in some

cases the RQ values could be reduced to below the LOCs for birds and/or mammals

.

2. PROBLEM FORMULATION

The problem formulation for this assessment, which discusses the stressor s , the conceptual

models used to estimate exposures to non

- target organisms, and the tools and methods with

which EPA will assess potential risk, was provided in the problem formulation document for the

registration review of clethodim, dated Aug. 13, 2008 (USEPA, 2008). 1 

## Updated information is

provided in this assessment.

2.1. Nature of the Stressor

Clethodim (PC code 121011) is a post

- emergen t selective herbicide used on a variety of crop s

and non

- crop areas to control a variety of grasses. As a cyclohexenone, clethodim is structurally

similar to and regarded as included in the cyclohexanedione family of herbic i des that inhibit lipid

synthesis by inhibiting the acetyl

- coenzyme A carboxyla se (ACCase) enzyme of grass species

(HRAC, 2012)

.

Clethodim and its transformation products that contain the cyclohexenone ring and organosulfur

side chain ( i.e. , with 5

- (2

- ethylthiopropyl)

- 5

- hydroxycyclohexene

- 3

- one or 5

- (2

-

1 

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

- HQ

- OPP

- 2008

- 0658

- 0008

## 1 2 ethylthiopropyl)cyclohexene

- 3

- one moieties) are the residues of concern (ROC) for this

assessment (USEPA, 2008). The products of concern include clethodim sulfoxide, clethodim

sulfone, clethodim oxazole, clethodim oxazole sulfoxide, clethodim oxazole sulfone, clethodim

imine, clethodi m imine sulfoxide, and clethodim trione sulfoxide. Ecotoxicity data are not

available for the transformation products of concern. Products of concern are assumed to be of

similar toxicity to the parent compound in the lack of data and because the toxic m oiety of the

active ingredient appears to potentially be intact.

2.2. Usage Update

The Agency’s Biological and Economic Analysis Division (BEAD) analysis of national

- level

agricultural usage information presented in the 2008 problem formulation (USEPA, 2008) was

updated on September 6, 2012, as presented in Table 2 (USEPA, 2012). Relatively small

changes in usage were observed in the 2012 update, which covered the 2003

- 2010 reporting

period. M ore than 400,000 pounds of clethodim are still used annually on agricultural crops

, with the highest annual usage, in terms of pounds of active ingredient (a.i.) applied, on soybeans

(200,000), sugar beets (50,000), sunflowers (40,000), and alfalfa (40,000). Usage on sugar beets

and cotton decreased, usage on alfalfa and dry beans/peas increased , while usage on soybeans

and sunflowers did not change . Maximum percent crop treated (PCT) values increased slightly

for most of the crops with the highest usage, with the highest PCT value (50%) occurring in

sugar beet usage.

Table 2. Screening Level Estimates of Agricultural Uses of Clethodim (Sep. 6, 2012) A,B,C



## Crop l bs. a.i. Percent Crop Treated

Average Maximum

1 Alfalfa 40,000 <2.5 5

2 Almonds <500 <1 <2.5

3 Apricots* <500 N/C N/C

4 Asparagus <500 5 15

5 Barley 1,000 <1 <2.5

6 Beans, Green 1,000 5 10

7 Broccoli 1,000 5 15

8 Brussels Sprouts* <500 N/C N/C

9 Cabbage <500 5 10

10 Caneberries <500 5 10

11 Canola 4,000 5 15

12 Cantaloupes <500 5 10

13 Carrots 2,000 15 40

14 Cauliflower <500 5 10

15 Celery < 500 5 10

16 Cherries <500 <1 <2.5

17 Corn 3,000 <1 <2.5

18 Cotton 10,000 <1 <2.5

## 13 Crop l bs. a.i. Percent Crop Treated

Average Maximum

19 Cucumbers <500 5 10

20 Dry Beans/Peas 10,000 5 15

21 Fallow 3,000 <1 <2.5

22 Garlic <500 5 15

23 Grapes <500 <1 <2.5

24 Lettuce <500 <1 <2.5

25 Nectarines* <500 N/C N/C

26 Onions 5,000 20 35

27 Peaches 1,000 5 10

28 Peanuts 20,000 10 15

29 Peas, Green <500 <2.5 5

30 Peppers 1,000 5 15

31 Pistachios* <500 N/C N/C

32 Plums/Prunes <500 <2.5 <2.5

33 Potatoes 5,000 5 10

34 Pumpkins 1,000 10 25

35 Rice 1,000 < 1 <2.5

36 Sorghum <500 <1 <2.5

37 Soybeans 200,000 5 10

38 Spinach <500 <1 <2.5

39 Squash <500 5 10

40 Strawberries <500 <2.5 10

41 Sugar Beets 50,000 30 50

42 Sunflowers 40,000 25 30

43 Tomatoes 2,000 5 10

44 Walnuts <500 <1 <2.5

45 Watermelons 2,000 10 25

46 Wheat <500 <1 <2.5

A 

### All numbers rounded (amounts ≥10,000 lbs a.i. bolded) (percentages ≥25% bolded)

. <500 Less than 500 pounds of active ingredient

<2.5 Less than 2.5 percent of crop treated

<1 Less than 1 percent of crop treated

* Based on CA DPR data, only LBS a.i. available . N/C= not calculated

B 

### SLUA data sources include (reporting t imeframe: 2003

- 2010) :

USDA

- NASS (United States Department of Agriculture's National Agricultural Statistics Service)

Private Pesticide Market Research

California DPR (Department of Pesticide Regulation)

C 

### These results reflect amalgamated data developed by the Agency and are releasable to the public.

## 14 3. ANALYSIS

3.1. Use Characterization

Clethodim is applied with aerial, ground, hand

- held, and irrigation equipment to a variety of

agricultural and non

- agricultural use sites. Approximately 67 uses and use groups ( i.e. , use sites)

are listed on dozens of end

- use labels registered by 21 regis trants. These use s and use groups are

organized into the following 26 maximum use patterns ( i.e.

, conservative use patterns that result

in maximum exposure following labeled directions) listed in Table 3 that are ranked by annual

application rate

. The use sites are not grouped by similarity and are not meant to be used as

surrogates for other use sites that share the same use pattern.

Many use sites have application rate limits on a seasonal or crop basis, not on an annual basis.

Annual applicat ion rates were assumed for use sites with multiple seasons per year, when not

specified on labels , based on estimates in USEPA, 2007 for California agriculture. These

estimates are more applicable to the lower latitudes of the United States and their appl icability is

complicated by the common practice of crop rotation. Specifically, for uses on alfalfa, fallow

land, and non

- cropped areas, the annual application rate was assumed to be 4.5 lbs a.i./A, which

represents nine cuttings of alfalfa per year, with 0.5 lbs a.i./A applied per cutting, or eighteen

applications per year on the other use sites. For grass for forage, fodder, or hay, eighteen

applications per year were also assumed. Other assumptions included five crops per year for

radishes, four crop s per year for turnip greens and mustard greens, and two crops per year for

sod, beets, and most brassica and leafy vegetable s (USEPA, 2007).

A r eapp lication interval of 14 days is labeled for a variety of uses. In the absence of label

directions, a reap plication interval of 7 days is assumed . This is the minimum interval assumed

to be practical for control of re

- emerged weeds following an earlier treatment

.

Table 3 . Maximum Use Patterns for Current Uses of Clethodim A



### Use Site(s) Single

App. Rate

(lbs a.i./A) Rea pp.

Interval B



### (days) Max. No.

of App.

per Crop App. Rate

per Crop

(lbs a.i./A) Annual

App. Rate C



### (lbs a.i./A) App.

Method D 

### Geo graphic

Applicability

Fallow land, golf course turf, non

cropped areas E 

### 0.25 NS F 

### NS NS 4.5 G 

### Aerial United States

Alfalfa I 

### 0. 25 NS NS 0.50 4.5 J 

### Aerial United States

Ornamentals, landscaped areas, non

bearing food crops H 

### , around

buildings, bare soil, mulched areas 0.25 14 NS NS 4.5 G 

### Ground United States

Grass forage/fodder/hay 0.19 NS NS NS 3.4 G 

### Sprayer MO only

Clover 0.25 NS NS 0.25 2.25 J 

### Aerial United States

Herbs, turnip greens 0.125 14 NS 0.50 2.0 N 

### Aerial United States

Mustard, vegetables 0.12 14 NS 0.485 1.9 N 

### Aerial ID only (and

OR & WA for

mustard)

Radishes 0.125 14 NS 0.25 1.25 M 

### Aerial United States

Mint 0. 25 14 NS 0.50 1.0 K 

### Aerial United States

Sod farms 0.25 NS NS 0.50 1.0 L 

### Aerial AL, FL, GA,

NC, SC only

## 15 Use Site(s) Single

App. Rate

(lbs a.i./A) Rea pp.

Interval B



### (days) Max. No.

of App.

per Crop App. Rate

per Crop

(lbs a.i./A) Annual

App. Rate C



### (lbs a.i./A) App.

Method D 

### Geo graphic

Applicability

Beets, brassica vegetables, carrots,

cranberries, cucurbit vegetables,

fruiting vegetables, leafy vegetables,

strawberries 0.125 14 NS 0.50 1.0 L 

### Aerial United States

Dried beans, Christmas trees, cotton,

forest trees, peanuts, potatoes, root &

tuber vegetables, sainfoin, soybeans,

sugar beets, sunflowers, sweet

potatoes, tomatoes, trefoil, yams 0. 25 NS NS 0.50 0.50 Aerial United States

Lentils 0.25 14 NS 0.50 0.50 Aerial United States

Garlic, onions 0.25 NS 2 0.50 0.50 Chemi

gation Except ID,

MT, OR, WA

Tree fruits, tree nuts, asparagus, hops,

safflower, sesame 0.125 NS NS 0.50 0.50 Aerial United States

Sage 0.24 NS NS 0.485 0.485 Ground NC only

Shallots 0.24 14 NS 0.485 0.485 Aerial United States

Artichokes, bushberries including

cranberries, caneberries, peaches 0.12 14 NS 0.485 0.485 Aerial United States

Flax 0.125 NS NS 0.25 0.25 Aerial Except CA

Meadowfoam 0.125 NS NS 0.25 0.25 Aerial OR only

Seeds 0.125 NS NS 0.25 0.25 Aerial MN, ND only

Kenaf 0.125 NS NS 0.25 0.25 Ground NC only

Canola 0.10 NS NS 0.25 0.25 Aerial United States

Wildlife food plots 0.24 14 NS NA F 

### 0.24 Not stated United States

Succulent beans, legume vegetables,

dried & succulent peas 0.125 NA 1 0.125 O 

### 0.125 Aerial United States

Corn (field) 0.045 NA 1 0.045 0.045 Aerial United States

A Listed use patterns represent those of the maximum use pattern and do not represent all labeled use patterns for

that use.

B Rea pplication intervals of 14 days were labeled for a variety of uses . I n the absence of label directions

, a

reapplication interval of 7 days is assumed for control of emerged weeds.

C The annual application rate accounts for how many crops may occur per year. For perennial crops ( e.g. , alfalfa),

the number of cuttings per year was used. Source: USEPA, 2007.

D Aerial application is assessed unless it is not allowed for the use.

E Non

- cropped areas include fallow agricultural land, rights

- of

- way, around airports, electric utilities, commercial

buildings, manufacturing plants, storage yards, rail yards, fence lines, parkways, golf courses, uncultivated

areas, and beneath greenhouse benches.

F NS means “not stated.” NA means “not applicable.”

G For non

- cropped areas, fallow land, golf course turf, and hay, eighteen applications were assumed in the absence

of a labeled annual application limit.

H Non

- bearing crops include apples, berries including strawberries, citrus fruits, grap es, olives, pears, stone fruits,

and tree nuts.

I Alfalfa use pattern includes an alfalfa plus clover mixture.

J For alfalfa, nine cuttings may occur per year in California . Nine cuttings were assumed for clover as well

(USEPA, 2007).

K Annual application rate is 1.04 lbs a.i./A for spearmint and 0.52 lbs a.i./A for peppermint.

L Two crops of sod, beets, and most brassica and leafy vegetables may be grown per year (USEPA, 2007).

M Radishes may have 5 crops per year (USEPA, 2007).

N Turnip gre ens and mustard greens may have 4 crops per year (USEPA, 2007).

## 16 O The seasonal application rate limit is stated as 0.50 lbs a.i./A; however, no more than one application of 0.125 lbs

a.i./A may be applied per season. Therefore, the practical seasonal rat e limit is 0.125 lbs a.i./A.



## 3.2. Environmental Fate Characterization

Clethodim is microbially oxidized to moderately persistent degradates within days of application.

Clethodim is soluble in water up to 29 mg/L and will not appreciably volatilize or bioconc entrate

in fish. The compound and its degradates are mobile in soil and may be transported to surface

waters and the degradates may be transported to ground waters. The available environmental

fate data for clethodim are listed in Table 4 . The informati on in this section is provided to

expand the brief characterization provided in the 2008 problem formulation for registration

review (USEPA, 2008).

Table 4. Chemical Properties and Environmental Fate Parameters of Clethodim

Parameter Value Source

Selected Physical/Chemical Parameters

Molecular mass (molecular formula) 359.92 g/mol ( C 12 

## H 10 

## Cl N 3 

## O) (Calculated)

Vapor pressure (25 °C) <1 x 10

- 7 

## torr MRID 48881401

Aqueous solubility (20 ° C) 29 mg/L MRID 48881405

Henry’s Law Constant (25 °C) <2 x10

- 9 

## atm

- m 3 

## /mol (Calculated)

Log octanol

- to

- water partition coefficient

(log K OW 

## ) 4.81 MRID 48881405

Dissociation constant (pKa ) 4.62 MRID 48881405

Persistence in Water

Hydrolysis half

- life (25 ° C) A 

## pH 5: 28 days

pH 7: 289 days

pH 9: 305 days MRID 40974520

Aqueous photolysis half

- life (25 ° C) pH 5: 1.5

- 1.7 days

pH 7: 2. 5

- 6.8 days

pH 9: 6.0

- 9.6 days MRID 41030133

, 41030134

Anaerobic aquatic metabolism half

- life

(25 ° C) 233 days MRID 41652301

Persistence in Soil

Aerobic soil metabolism half

- life (25°C) 1.2 days MRID 41376801

2.5 days MRID 4 0974522

Photolysis half

- life in soil (13

- 23 ° C) 7 days MRID 41030135

Mobility

Freundlich soil

- water partition

coefficients (K F 

## ); Freundlich organic

carbon

- normalized coefficients (K FOC 

## ) 0.08

, 0.15

, 0.46

, 0.51, 1.57 L/kg;

4.9

, 65

, 68

, 132, 271 L/kg OC 

## MRID 4 0974523

## 17 Parameter Value Source

Field Dissipation

Terrestrial field dissipation half

- life Half

- lives and leaching depths coul d not

be calculated due to high LOQs (20 ppb)

relative to dose rates (MS cotton ; CA

cotton; NC soybean ; and IA soybean

sites) MRID 41030207

MRID 41030208

(MRID 41030209) B



## (MRID 41030210) B



## Fish Bioconcentration

Fish bioconcentration factors (steady

state, total residues); depuration rate 0.7

- 2.1 ( edible ), 3 .0

- 4 .0 (ine dible ),

2.3

- 3.6 ( whole fish );

> 70% depuration in 3

- 14 days MRID 409745 24 /

409745 3 1

A 

### Technically, clethodim underwent non

- hydrolytic, abiotic, thermal degradation in the presence of aqueous buffers.

Half

- life values only represent the propyl

- labeled studies because allyl

- labeled clethodim was not studied at pH 9

and was studied at an elevated concentration at pH 5 and 7.

B 

### Studies with MRIDs in parentheses are provisional until reviewed.



## Clethodim and many of its degradates have multiple types of isomerization. The compound is a n

equili brium mixture of four tautomers, which are predominantly two keto

- enol tautomers at the

cyclohexene ring (MRID 41376801). The other two tautomers, which are cyclohexane diones

with tautomerization at the oxime, may be intermediates. Clethodim als o has two chiral centers

along the thiopropyl side chain and two double bonds that can form cis

- trans isomers.

Clethodim and its degradates include only the E

- isomer of the chloropropenyl group. Clethodim

is a racemic mixture, however, of the sixteen combinations of the other two cis

- trans isomer s

, four enantiomers, and two predominant tautomers. MRID 41376801 Appendix D provides a

more complete discussion of the complex isomerism in clethodim and its degradates. I somerism

complexity often co mplicates study results because multiple observed chromatograph peaks may

represent isomers or tautomers of the same compound. When this occurs, the concentrations of

isomers or tautomers are summed together to represent a total concentration for the comp ound.

In the fish bioconcentration (BCF) studies, clethodim and its sulfoxide were identified and

quantified in the tank water and identified in the fish. Residue concentrations were too low to

quantify clethodim or its sulfoxide in fish or to identify a ny other metabolites in fish that may

have been present at lower concentrations than the sulfoxide. Total

- residue fish BCF values for

whole fish were 2.3

- 3.6x. Allyl

- labeled residues depurated from fish by 72% in 14 days.

Cyclohexenone

- labeled residues depurated from fish faster, by >70% in 3 days. Due to the low

bioconcentration of clethodim residues and their relatively rapid depuration, bioaccumulation of

clethodim residues of concern in aquatic organisms is not expected.

Degradates of clethodim and their amounts formed in submitted studies are listed in Table 6

. Clethodim sulfoxide is the main degradate of clethodim, formed in soil at up to 75% of the

applied compound three days after application. Clethodim sulf one forms up to 16% of the

applied 3 0 days after application. These degradates are more persistent than the parent

compound, but not expected to generally persist, with 0.4

- 0.9% of the applied remaining 380

days after application

. Clethodim oxazole sulfone does persist, with up to 10% of t he applied at

study termination, 380 days after application. Nine additional major photolysis degradates are

## 18 formed in shallow, clear, well

- lit water bodies; however, most of the applied clethodim is likely

to biodegrade prior to reaching a water body, pr ior to photolyzing, or both.

C lethodim ’s sulfoxide and sulfone are more mobile than clethodim in soil

. However,

clethodim’s oxazole sulfoxide is less mobile in soil than the parent compound. Table 5 lists the

available environmental fate information for degradates of clethodim , which is only focused on

soil mobility

.

Table 5

. Environmental Fate Parameters of Clethodim Degradates

Parameter Degradate Value Source

Freundlich organic

carbon

- normalized

coefficients (K FOC 

## ) Clethodim sulfoxide 12

, 27

, 3 8, 57

, 86 L/kg OC



## MRID 40974523 Clethodim sulfone 6

, 13

, 19

, 29

, 43 L/kg OC



## Clethodim oxazole sulfoxide 50

, 135

, 429

, 460

, 771 L/kg OC

## 19 Table 6. Chemical Names and Structures of Clethodim and Its Environmental Degradates A



## Code Name/

S ynonym Chemical N ame Chemical S tructure Study Type Ref. B



## (MRID) Maximum

%AR (day) Final %AR

(study length)

PARENT



## Clethodim

RE

- 45601

(Z

- isomer is

RE

- 46116) (5 RS )

- 2

- {(1 EZ )

- 1

- [(2 E )

- 3

- chloroallyloxyimino]propyl}

- 5

- [(2 RS )

- 2

- (ethylthio)propyl]

- 3

- hydroxycyclohex

- 2

-

en

- 1

- one

CAS No.: 99129

- 21

- 2

Formula: C 17 

### H 2 6 

### ClNO 3 

### S

MW: 359.92 g/mol

SMILES: C1C(CC(=C(C1=O) \ C(CC)=N

\ OCC=CCl)O)CC(C)SCC S O H O

N O Cl



### TRANSFORMATION PRODUCTS



## Clethodim

s ulfoxide

RE

- 45924

CLSO

SOX (5 RS )

- 2

- {(1 EZ )

- 1

- [(2 E )

- 3

- chloroallyloxyimino]propyl}

- 5

- [(2 RS )

- 2

- (ethy lsulfinyl )propyl]

- 3

- hydroxycyclohex

- 2

- en

- 1

- one

Formula: C 17 

### H 26 

### ClN O 4 

### S

MW: 375.92 g/mol

SMILES: C1C(CC(=C(C1=O) \ C(CC)=N

\ OCC=CCl)O)CC(C)[S](CC)=O

S O H O

N O Cl

O 

### Hydrolysis

– pH 5

Hydrolysis

– pH 7

Hydrolysis

– pH 9 40974520 2.6% (0 d)

3.0% (14 d)

5.3% (14 d) 1.7% (32 d)

2.0% (32 d)

4.5% (32 d)

Aq. photo.

– dark

Aq. photo.

– light 4 1030133 5.2% (3 d)

14% ( 3 d) 1.4% (10 d)

nd (30 d)

Aq. photo.

– dark

Aq. photo.

– light 4 1030134 3.6% (3 d)

14% ( 30 d) 2.7% (10 d)

14% ( 30 d)

Aq. photo.

– dark

Aq. photo.

– light 4 4066701 4.6% (25 d)

7.6% (1 d) 4.4% (3 0 d)

nd (30 d)

Soil photo.

– dark

Soil photo.

– light 4 1030135 64% (7 d)

74% (4 d) 64% (7 d)

71 % (7 d)

Aerobic soil 40974522 65 % (7 d) nd (380 d)

Aerobic soil 41376801 75 % (3 d) 0.9% (121 d)

Anaerobic aquatic 41652301 

### 23

- 38% B 

### (181 d) 23

- 38% B 

### (181 d)



## Clethodim

sulfone

RE

- 47253

ONE (5 RS )

- 2

- {(1 EZ )

- 1

- [(2 E )

- 3

- chloroallyloxyimino]propyl}

- 5

- [(2 RS )

- 2

- (ethy lsulfonyl )propyl]

- 3

- hydroxycyclohex

- 2

- en

- 1

- one

Formula: C 17 

### H 26 

### ClN O 5 

### S

MW: 391.92 g/mol

SMILES: C1C(CC(=C(C1=O) \ C(CC)=N

\ OCC=CCl)O)CC(C)[S](CC) (=O) =O S O H O

N O Cl

O O 

### Aerobic soil 40974522 12 % (62 d) 0.4% (380 d)

Aerobic soil 41376801 16 % (30 d) 5.6 % (121 d)

Anaerobic aquatic 41652301 0.6% (42 d) nd (181 d)

## 20 Code Name/

S ynonym Chemical N ame Chemical S tructure Study Type Ref. B



## (MRID) Maximum

%AR (day) Final %AR

(study length)

Clethodim

oxazole

RE

- 47365

CLOX

OX (±)

- 6,7

- dihydro

- 2

- ethyl

- 6

- [2

- (ethylthio)propyl]

- 4(5H)

- benzoxazolone

Formula: C 14 

### H 21 

### N O 2 

### S

MW: 267.39 g/mol

SMILES: C12=C(OC(=N1)CC)CC(CC2

=O)CC(C)SCC O N

S O 

### Hydrolysis

– pH 5

Hydrolysis

– pH 7

Hydrolysis

– pH 9 40974520 54% (32 d)

7.3% (32 d)

5.1% (32 d) 54% (32 d)

7.3% (32 d)

5.1% (32 d)

Aq. photo.

– dark

Aq. photo.

– light 4 1030134 14% (2.5 d)

5.5 % ( 3 d) 14% (2.5 d)

0.5% (14 d)

Aq. photo.

– dark

Aq. photo.

– light 4 4066701 34% (30 d)

12% (1 .5 d) 34% (3 0 d)

nd (30 d)

Aerobic soil 40974522 2.1% ( 3 d) nd (380 d)

Anaerobic aquatic 41652301 1.2% (181 d) 1.2% (181 d)



## Clethodim

oxazole

sulfoxide

RE

- 47796

OXSO

OXSOX (±)

- 6,7

- dihydro

- 2

- ethyl

- 6

- [2

- (ethylsulfinyl)propyl]

- 4(5H)

-

benzoxazolone

Formula: C 14 

### H 21 

### N O 3 

### S

MW: 283.39 g/mol

SMILES: C12=C(OC(=N1)CC)CC(CC2

=O)CC(C)[S](CC)=O O N

S O

O 

### Aq. photo.

– dark

Aq. photo.

– light 4 1030134 1.2% (2.5 d)

5.9% (10 d) 1.0% (14 d)

nd (30 d)

Aq. photo.

– dark

Aq. photo.

– light 4 4066701 1.9% (30 d)

8.9 % ( 6 d) 1.9% (3 0 d)

2.2% (30 d)

Aerobic soil 40974522 6.1% (90 d) 3.0% (380 d)

Aerobic soil 41376801 5.3% ( 30 d) 4.9 % (121 d)

Anaerobic aquatic 41652301 10% (70 d) 7.7% (181 d)



## Clethodim

oxazole

sulfone

RE

- 47797

OXONE (±)

- 6,7

- dihydro

- 2

- ethyl

- 6

- [2

- (ethylsulfonyl)propyl]

- 4(5H)

-

benzoxazolone

Formula: C 14 

### H 21 

### N O 4 

### S

MW: 299.39 g/mol

SMILES: C12=C(OC(=N1)CC)CC(CC2

=O)CC(C)[S](CC) (=O) =O O N

S O

O O 

### Aerobic soil 40974522 10% (380 d) 10% (380 d)

Aerobic soil 41376801 8.6 % ( 121 d) 8.6 % ( 121 d)

Anaerobic aquatic 41652301 5.1% (181 d) 5.1% (181 d)



## Clethodim

imine

RE

- 47686

CLIM

IMINE (±)

- 5

- [2

- (ethylthio)propyl]

- 3

- hydroxy

- 2

- (1

- iminopropyl)cyclohex

- 2

- enone

Formula: C 14 

### H 23 

### N O 2 

### S

MW: 269.41 g/mol

SMILES: C1C(CC(=C(C1=O)C(CC)=N)

O)CC(C)SCC 

### S O H O

N H Aq. photo.

– light 4 1030134 18% ( 2.5 d) 18% ( 2.5 d)

Aq. photo.

– dark

Aq. photo.

– light 4 4066701 1.4% (25

- 30 d)

28% ( 2 d) 1.4% (3 0 d)

nd (30 d)

Anaerobic aquatic 41652301 

### 1.3

- 17% B



### (181 d) 1.3

- 17% B 

### (181 d)

## 21 Code Name/

S ynonym Chemical N ame Chemical S tructure Study Type Ref. B



## (MRID) Maximum

%AR (day) Final %AR

(study length)

Clethodim

imine

sulfoxide

RE

- 47718

IMSO

IMSOX (±)

- 5

- [2

- (ethylsulfinyl)propyl]

- 3

- hydroxy

- 2

- (1

- iminopropyl)cyclohex

- 2

-

enone

Formula: C 14 

### H 23 

### N O 3 

### S

MW: 285.41 g/mol

SMILES: C1C(CC(=C(C1=O)C(CC)=N)

O)CC(C)[S](CC)=O 

### S O H O

N H

O Aq. photo.

– light 4 1030134 23 % ( 21 d) 20 % ( 30 d)

Aq. photo.

– dark

Aq. photo.

– light 4 4066701 0.5% (25 d)

30% (1 0 d) 0.4% (3 0 d)

11% (30 d)

Aerobic soil 40974522 1.1% (14

- 30 d) nd (380 d)

Aerobic soil 41376801 2.1 % ( 3 d) 2.0 % ( 121 d)

Anaerobic aquatic 41652301 1.6% (181 d) 1.6% (181 d)



## Clethodim

imine ketone

IMK (±)

- 5

- [propyl

- 2

- one]

- 3

- hydroxy

- 2

- (1

- iminopropyl)cyclohex

- 2

- enone

Formula: C 12 

### H 17 

### N O 3



### MW: 223.27 g/mol

SMILES: C1C(CC(=C(C1=O)C(CC)=N)

O)CC(=O)C 

### O

O H O

N H Aq. photo.

– light 4 1030134 12% ( 15, 25 d) 9.5 % ( 30 d)

Aq. photo.

– light 4 4066701 15 % ( 2

- 4 d) 5.8% (30 d)



## Clethodim

trione

TRIONE (±)

- 5

- [2

- (ethylthio)propyl]

- 3

- hydroxy

- 2

- (1

- oxopropyl)cyclohex

- 2

- enone

Formula: C 14 

### H 22 

### O 3 

### S

MW: 270.39 g/mol

SMILES: C1C(CC(=C(C1=O)C(CC)=O)

O)CC(C)SCC 

### S O H O

O Aq. photo.

– light 4 4066701 2.9 % ( 7 d) nd (30 d)



## Clethodim

trione

sulfoxide

RE

- 47386

TRISO (±)

- 5

- [2

- (ethylsulfinyl)propyl]

- 3

- hydroxy

- 2

- (1

- oxopropyl)cyclohex

- 2

-

enone

Formula: C 14 

### H 22 

### O 4 

### S

MW: 286.39 g/mol

SMILES: C1C(CC(=C(C1=O)C(CC)=O)

O)CC(C)[S](CC)=O 

### S O H O

O

O Aq. photo.

– light 4 1030134 4.4% ( 0.5 d) 2.7% (2.5 d)

Aq. photo.

– light 4 4066701 18% ( 20

- 30 d) 18% (30 d)



## Clethodim

trione

ketone (±)

- 5

- [propyl

- 2

- one]

- 3

- hydroxy

- 2

- (1

- oxopropyl)cyclohex

- 2

- enone

Formula: C 12 

### H 16 

### O 4



### MW: 224.26 g/mol

SMILES: C1C(CC(=C(C1=O)C(CC)=O)

O)CC(=O)C 

### O

O H O

O Aq. photo.

– light 4 1030134 5.3% (2 0 d) 4.8 % (30 d)

## 22 Code Name/

S ynonym Chemical N ame Chemical S tructure Study Type Ref. B



## (MRID) Maximum

%AR (day) Final %AR

(study length)

Clethodim

imine ketone

IMK (±)

- 5

- [propyl

- 2

- one]

- 3

- hydroxy

- 2

- (1

- iminopropyl)cyclohex

- 2

- enone

Formula: C 12 

### H 17 

### N O 3



### MW: 223.27 g/mol

SMILES: C1C(CC(=C(C1=O)C(CC)=N)

O)CC(=O)C 

### O

O H O

N H Aq. photo.

– light 4 1030134 12% ( 15, 25 d) 9.5 % ( 30 d)

Aq. photo.

– light 4 4066701 15 % ( 2

- 4 d) 5.8% (30 d)



## DME

sulfoxide

RE

- 52453

DMESO (±)

- 3

- [2

- (ethylsulfinyl)propyl]pentanedioic acid

Formula: C 10 

### H 18 

### O 5 

### S

MW: 250.32 g/mol

SMILES: C(C(CC(=O)O)CC(C)[S](CC)

=O)C(=O)O 

## S

O O

O O H

O H Aq. photo.

– light 4 1030134 49% ( 30 d) 49% ( 30 d)

Aq. photo.

– light 4 4066701 11 % ( 20

- 30 d) 11 % (30 d)



## DME sulfone

DMESO2 (±)

- 3

- [2

- (ethylsulfonyl)propyl]pentanedioic acid

Formula: C 10 

### H 18 

### O 6 

### S

MW: 266.32 g/mol

SMILES: C(C(CC(=O)O)CC(C)[S](CC)(

=O)=O)C(=O)O 

## S

O O

O O H

O H O Aq. photo.

– light 4 1030134 7.4% (30 d) 7.4% (30 d)



## Unknown

- 2 (±)

- 3

- [propyl

- 2

- one]pentanedioic acid

(proposed chemical name)



## O O

O O H

O H

(proposed chemical structure) Aq. photo.

– light 4 1030134 7.4% (30 d) 7.4% (30 d)



## 3

- chloroprop

enal ( E )

- 3

- chloro propenal

Formula: C 3 

### H 3 

### ClO

MW: 90.51 g/mol

SMILES: O=CC=CCl 

## O Cl Aq. photo.

– light 4 1030133 31 % ( 2.5 d) 31 % ( 2.5 d)



## Chloroallyl

alcohol

RE

- 46261 ( E )

- 3

- chloroallyl alcohol

Formula: C 3 

### H 5 

### ClO

MW: 92.53 g/mol

SMILES: OCC=CCl 

## O H Cl Hydrolysis

– pH 5

Hydrolysis

– pH 7 40974520 35 % (30 d)

5.3% (30 d) 35 % (30 d)

5.3% (30 d)

Aq. photo.

– dark

Aq. photo.

– light 4 1030133 11% (2.5 d)

31 % ( 15 d) 11% (2.5 d)

29 % ( 30 d)

## 23 Code Name/

S ynonym Chemical N ame Chemical S tructure Study Type Ref. B



## (MRID) Maximum

%AR (day) Final %AR

(study length)

Unextracted

residues (not applicable)



### (n ot applicable ) Soil photo.

– dark

Soil photo.

– light 41030135 5.5% (7 d)

6.2% (7 d) 5.5% (7 d)

6.2% (7 d)

Aerobic soil 40974522 23 % (183 d) 18% (380 d)

Aerobic soil 41376801 29 % (125 d) 29 % (125 d)

Anaerobic aquatic 41652301 11% (181 d) 11% (181 d)



## Carbon

dioxide Carbon dioxide

Formula: CO 2



### MW: 44. 0 1 g/mol

SMILES: O=C=O 

# O O Aq. photo.

– light 4 1030133 12 % ( 30 d) 12 % ( 30 d)

Soil photo.

– dark

Soil photo.

– light 41030135 3.7 % (7 d)

4.2% (7 d) 3.7 % (7 d)

4.2% (7 d)

Aerobic soil 40974522 54 % (380 d) 54 % (380 d)

Aerobic soil 41376801 57 % (121 d) 57 % (121 d)

Anaerobic aquatic 41652301 0.1% (181 d) 0.1% (181 d)

A 

### nd means “not detected” . AR means “applied radioactivity”. MW means “molecular weight”. Bolded values are laboratory study values >10%AR.

B 

### These values have a range because portions of the sulfoxide and imine degradates co

- eluted and the proportions of the mixture are unclear, i.e.

, whether the residue was one

degradate, the other, or both.

## 24 3.3. Exposure Characterization

The available physical/chemical and environmental fate properties of clethodim and its

degradates of concern were used to calculate exposure model input parameters to estimate

potential environmental concentrations . The compounds of concern include those with 5

- (2

- ethylthiopropyl)

- 5

- hydroxycyclohexene

- 3

- one or 5

- (2

- ethylthiopropyl)cyclohexene

- 3

- one

moieties. Half

- lives calculated for the residues of conc ern (ROC) are listed in Table 7

. Also

listed is the soil mobility of the most prominent residue of concern, clethodim sulfoxide, which is

used to represent the residues of concern.

Table 7. Environmental Fate Parameters of Clethodim Residues of Concern ( ROC)

Parameter Value Source

Persistence in Water

Hydrolysis half

- life (25 ° C) pH 5: 414 days

pH 7: 3,660 days

pH 9: 45,000 days MRID 40974520

Aqueous photolysis half

- life (25 ° C) pH 5: 2.1

- 8.0 days

pH 7: 4.1

- 24 days

pH 9: 7.5

- 27 days MRID 41030133

, 41030134

Anaerobic aquatic metabolism half

- life

(25 ° C) 1217 days MRID 41652301

Persistence in Soil

Aerobic soil metabolism half

- life (25°C) 44 days MRID 41376801

87 days MRID 4 0974522

Photolysis half

- life in soil (13

- 23 ° C) No observable degradation MRID 41030135

Mobility

Freundlich organic carbon

- normalized

coefficients (K FOC 

## ) 12

, 27

, 3 8, 57

, 86 L/kg OC 

## MRID 40974523



## 3.3.1. Aquatic Exposure

The Total Residue (TR) modeling approach was used to estimate aquatic exposure with the ROC

half

- lives (from Table 7 ) , the soil mobility of clethodim sulfoxide (from Table 7 ) , and the

physical/chemical properties of clethodim (from Table 4 )

. The TR approach is appropriate

because there are multiple degradates of concern, for none of which a full environmental fa te

data profile is available , and the toxic moiety of the active ingredient appears to potentially be

intact. Because up to 75% of clethodim oxidizes to its sulfoxide in soil , the sulfoxide is the most

prominent degradate of concern. With a mean K OC 

## valu e of 44 L/kg, clethodim sulfoxide is

more mobile in soil than clethodim and its oxazole sulfoxide, but less mobile in soil than

clethodim sulfone; therefore, use of its K OC 

## value in modeling may be representative and may be

conservative, but is not a worst case assumption. PE chemical inputs for the ROC are listed in

Table 8

.

## 25 Table 8

. PE Chemical Input Parameters for Clethodim Residues of Concern

Input Parameter Value Justification Source

Molecular Mass (g/mol) 359.9 Product chemistry data (Calculated)

Henry’s Law Constant

(atm m 3 

## /mol) 2 .0 × 10

- 9 

## Ratio of vapor pressure to water

solubility (Calculated from

MRID s 4 8881401

and 48881405 )

Solubility in Water (mg/L) 29 Study value for clethodim MRID 48881405

Organic Carbon Partition

Coefficient (K OC 

## ) (L/kg OC 

## ) 44 Mean value for clethodim sulfo xide, the

most prominent degradate of concern MRID 4 0974523

Aerobic Soil Metabolism

Half

- life (days) 132 90 th 

## percentile confidence bound on the

mean total residue value for two soils MRID s 4 0974523

and 41376801

Aerobic Aquatic Metabolism

Half

- life (days) 264 Aerobic soil metabolism input value

times two MRID s 4 0974523

and 41376801

Anaerobic Aquatic

Metabolism Half

- life (days) 3650 Single available anaerobic aquatic

metabolism value times three MRID 4 1652301

Hydrolysis Half

- life at pH 7

(days) 3660 Study value for clethodim residues of

concern MRID 40974520

Aqueous Photolysis

Half

- life (days) 24 Maximum s tudy value for clethodim

residues of concern MRID 41030134



## PRZM use pattern inputs are listed in Table 9

. Modeled PRZM scenarios were those applicable

to the use sites that resulted in the highest exposure

, resulted in exposure bracketing

toxicological levels of concern , or were otherwise modeled for characterization . In the interest

of concision and resou rce savings, not all labeled uses of clethodim were modeled. This is

because the pesticide is labeled for use on approximately 67 uses and use groups and risk

conclusions are similar for many of them. Modeled use sites are not surrogates for other use

si tes not modeled. Exposure estimates from modeled use sites are used to bracket toxicological

levels of concern

, which allows for the characterization of the risks for all use sites. In this

assessment, r isk conclusions were the same for all 67 use sites. It only takes two crops (the crop

of highest exposure and the crop of lowest exposure) to bracket the rest and show that risk

conclusions are the same for all crops. To identify these two crops

, use sites expected to produce

high exposure, such as alfalf a

, and use sites expected to produce low exposure, such as corn,

were modeled for risk estimation.

Modeled application rates and num bers of applications per year include the maximum allowed

on a label. Dates of initial application were selected within th e scenario crop season (if allowed

by the number of applications per year) and characterized by vulnerability to runoff. Runoff

vulnerability was explored by modeling a range of initial application dates falling on the 1 st 

## or

15 th 

## of months within the cro p season and selecting the date for which exposure estimates were

highest. This was expected to produce high

- end exposure estimates that are conservative but that

may not represent the highest possible exposure.

## 26 Table 9 . PRZM Scenarios and Input P aramete rs Describing Maximum Patterns of

Clethodim Use on Representative Use Sites A



### Use Site PRZM

Scenario Date of

Initial

App. App. Rate in

lbs a.i./A

(kg a.i./ha) App.

per

Year App.

Interval

(days) CAM

Input IPSCND

Input Application

Efficiency/

Spray Drift

Alfalfa NC alfalfa May 1 5 0.25 (0.28) 18

7 B 

### 2 3 0.95/0.05

Jun. 1 1

Hay MO melon C 

### Apr. 1 0.19 (0.21) 18

7 B 

### 2 2 0.99/0.01

3

Fallow/non

cropped areas FL turf Jun. 1

0.25 (0.28) 18

7 B 

### 2 3 0.95/0.05 Mar. 15 6

Apr. 1 1

Ornamentals CA nursery Mar. 15 0.25 (0.28) 18 14 2 3 0.99/0.01

Cotton MS cotton Sep. 1 0.25 (0.28) 2

7 B 

### 2 3 0.95/0.05

1

Peanuts NC peanut Sep. 15 0.25 (0.28) 2 7 B 

### 2 1 0.95/0.05

Asparagus MI asparagus Sep. 1 0.125 (0.14) 2 7 B 

### 2 2 0.95/0.05

Hops OR hops Jun. 1 0.125 (0.14) 2 7 B 

### 2 2 0.95/0.05

Legumes MS soybean Sep. 15 0.125 (0.14) 1 N/A 2 1 0.95/0.05

Corn K S corn Aug. 1 0.045 (0.050) 1 N/A 2 2 0.95/0.05

A 

### Multiple numbers of applications per year were modeled for some use sites to explore risk conclusions. Where

multiple dates of initial application are listed for a use site, they correspond to the number of applications per year in

the table row.

B 

### A 7

- da y interval for control of emerged weeds was assumed in the absence of label directions.

C 

### The Missouri melon scenario was used for hay because the hay use pattern is limited to the State of Missouri.



## S urface water exposure estimates per use site for cleth odim residues of concern are listed in

Table 10 . Model input and output files are attached in Appendix A

. The maximum use pattern

on alfalfa results in the highest environmental exposure concentrations (EEC).

Table 10. Aquatic Exposure Estimate s from Clethodim Use Sites A



## Use Site PRZM Scenario 1

- in

- 10

- year Peak

(μg/L) 1

- in

- 10

- year 21

- day Mean (μg/L) 1

- in

- 10

- year 60

- day Mean (μg/L)

Alfalfa NC alfalfa 1 13 1 10 1 08

Hay MO melon 42 41 39

Fallow/non

- cropped areas FL turf 29 29 28

Ornamentals CA nursery 36 36 34

Cotton MS cotton 26 25 24

Peanuts NC peanut 16 16 16

Asparagus MI asparagus 3.9 3.9 3.8

Hops OR hops 2.6 2.6 2.5

Legumes MS soybean 6.3 6.1 5.8

Corn KS corn 6.2 6.1 5.8

A 

### Maximum values are in bold.

## 27 For characterization, surface water exposure was also estimated for clethodim, without the

degradates of concern. Model inputs for clethodim alone were the same as for the total residues

of concern model run for use on alfalfa, with the following clethodim

- specific differences: a K OC



## of 108 L/kg, an aerobic soil metabolism half

- life of 3.8 days, an aerobic aquatic metabolism half

life of 7.5 days, an anaerobic aquatic metabolism half

- life of 699 days, a hydrolysis half

- life of

289 days, and an aqueous photolysis half

- life of 6.8 days. The r esulting 1

- in

- 10

- year clethodim

only EECs were 29 μg/L (peak), 15 μg/L (21

- day mean), and 8.6 μg/L (60

- day mean).

3.3.1.1. Bioaccumulation

Clethodim residues of concern are not expected to appreciably bioaccumulate in aquatic or

terrestrial organisms. With a log K OW 

## of 4.81, clethodim meets the criteria for chemicals that are

modeled with KABAM for bioaccumulation in birds and mammals . Bioaccumulation modeling

was not conducted, however, because of the following consideration s:

• The submitted fish BCF study indicates that clethodim residues do not appreciably

bioconcentrate, with whole

- fish BCF values of 2

- 4 x. Depuration from fish was relatively

quick (> 7 0 % depuration in 3

- 14 days ).

• Clethodim is rapidly biodegraded in aerobic conditions (half

- lives of 1

- 7 days), typically

to more polar degradates that are expected to be easier to metabolize and to have lower

K OW 

## values than clethodim.

• Clethodim is of low toxicity to birds and mammals on acute and chronic exposure basi s,

with respective NOAECs of 833 an d 500 mg/kg

- diet ( ppm ) . No reproductive effects

were observed in either the avian or mammalian reproduction toxicity tests

.

3.3.1.2. Monitoring Data

C lethodim is not an analyte in the following water monitoring programs : the California

Department of Pesticide Regulation ( CDPR) surface water database

( http://www.cdpr.ca.gov/docs/emon/surfwtr/surfcont.htm

, the USGS NAWQA surface and

ground water database ( http://infotrek.er.usgs.gov/apex/f?p=136:1:0::NO::: ), the USEPA

STORET Data Warehouse ( http://www.epa.gov/storet/ ), and the USDA Pesticide Data Program

drinking water monitoring analyses

( http://www.ams.usda.gov/AMSv1.0/ams.fetchTemplateD ata.do?template=TemplateG&navID=

&rightNav1=&topNav=&leftNav=ScienceandLaboratories&page=PDPDownloadData/Reports&

resultType=&acct=pestcddataprg )

.

3.3.2. Terrestrial Exposure

3.3.2.1. Dietary Modeling

Terrestrial exposure estimates for avian and mammalian risk assessment s were derived using the

T

- REX model (version 1.5.1, 05/22/2013). In this model, the assumption is that the bird or

mammal receives 100% of their diet f or one day from on

- field items. The exposure estimates for

birds are considered to be surrogates for e xposures to terrestrial

- phase amphibians and reptiles.

## 28 Crop Uses

For clethodim application to crops, a foliar application in T

- REX was used. Potential dietary

exposure for terrestrial wildlife in this assessment is based on consumption of clethodim residues

on food items following spray applications. The input parameters are presented in Table 11

. An

evaluation into a potential foliar dissipation half

- life rate was conducted; however, none of the

available information could be used to refine the foliar dissipation half

- life. Therefore, when data

are absent, as in this case, EFED uses the default fol iar dissipation rate of 35 days based on the

work of Willis and McDowell (1987)

. Reapplication intervals of 14 days were labeled for a

variety of uses ; however, i n the absence of label directions, a reapplication interval of 7 days is

assumed for control of emerged weeds. Also, the annual application rate accounts for how many

crops may occur per year. For perennial crops ( e.g. , alfalfa), the number of cuttings per year was

used (USEPA, 2007)

.

For the preliminary assessment, terrestrial dietary and dos e

- based EECs of clethodim residues on

food items were derived using the range of application rates for clethodim ( Table 12 through

Table 14 )

. The acute avian toxicity studies were all non

- definitive endpoints, and only the most

sensitive size class, small (20g) birds, was modeled for dose

- based EECs ( Table 1 3 ). For acute

mammalian toxicity, the two most sensitive size class, small (15g) and medium (35g) mammals

were modeled for dose

- based EECs ( Table 1 4 ). A ll use patterns (with aerial, ground, or

chemigation application methods) with total annual application rates less than 0.5 lb a.i./A were

not modeled, as it was determined

, based on the modeled values of representative crops, these

uses do not pose risk to birds and/or mammals on an acute or chr onic basis (see Table 3 for a list

of applicable uses ; and Section 5

- Risk Description

, for additional discussion )

. Example

input/outputs from T

- REX for clethodim can be found in Appendix B

.

Table 11

. Input Parameters for T

- REX Modeling for the Scenarios

Use(s) Single

App. Rate

(lbs a.i./A) Maximum

Annual App. Rate

(lbs a.i./A) Maximum

No. of

App. Minimum

Reapplication

Interval (days)

F allow land, golf course turf,

& non

- cropped areas 0.2 5 4.5 A 

### 18 A 

### 7

- d B



### Ornamentals, landscaped areas,

non

- bearing food crops, around

buildings, bare soil, & mulched

areas 0.2 5 4.5 A 

### 18 A 

### 14

- d B



### A lfalfa 0.2 5 4.5 C 

### 18 C 

### 7

- d B



### Dr ied beans, Christmas trees,

cotton, forest trees, peanuts,

potatoes, sainfoin, soybeans,

sugar beets, sunflowers, sweet

potatoes, tomatoes, trefoil,

yams

, & lentils 0.2 5 0.5 2 7

- d B



### Mint

(spearmint, peppermint) 0.2 5 1.0 E 

### (spearmint) 4 E 

### (spearmint) 14

- d (spearmint)

0.5 E 

### (pe p per mint) 2 E 

### (peppermint) 14

- d (peppermint)

Clover 0.2 5 2.25 D 

### 9 D 

### 7

- d B



### Sod Farms 0.2 5 1.0 F 

### 4 F 

### 7

- d B



### Grass forage/fodder/hay 0.19 4.5 A 

### 18 A 

### 7

- d B

## 29 Use(s) Single

App. Rate

(lbs a.i./A) Maximum

Annual App. Rate

(lbs a.i./A) Maximum

No. of

App. Minimum

Reapplication

Interval (days)

Radishes 0.125 1.25 G 

### 10 G 

### 14

- d

Beets, Brassica vegetables,

& leafy vegetables 0.125 1.0 F 

### 8 F 

### 14

- d

Turnip & mustard greens 0.125 2.0 H 

### 16 H 

### 14

- d



## Abbreviations: App. 

## Application(s)

A 

### For non

- cropped areas, fallow land, ornamenta ls, golf course turf, and hay, 18 applications were assumed in the

absence of a labeled annual application limit.

B 

### The labels do not specify minimum reapplication intervals for a large number of uses. When th e reapplication

interval is not specified, an assumed reapplication interval of 7 days may be used in the assessment

C 

### For alfalfa there are 2 applications per crop, and alfalfa and clover may have 9 cuttings per year in California ;

therefore for one (1) year of application a total of 18 applications were used for modeling the alfalfa use

. D 

### For clover there is 1 application per crop, and alfalfa and clover may have 9 cuttings per year; therefore for one (1)

year of application a total of 9 applications were used for modeling the clover use.

E 

### Annual application rate is 1.0 lbs a.i./A for spearmint and 0.5 0 lbs a.i./A for peppermint

F 

### For sod, beets, and brassica and leafy vegetables there are four applications per crop, and sod, beets, and most

brassica and leafy vegetables may be grown twice per year; therefore for one (1) year of application a total of 8

applications were used for modeling sod, beets, and brassica and leafy vegetables uses.

G 

### For radishes there are 2 applications per crop, and radishes may have 5 crops per year; therefore for one (1) year of

application a total of 10 applications were used for modeling the radishes use

. H 

### For turnip greens and mustard greens there are 4 applications per crop, and turnip greens and mustard greens may

hav e 4 crops per year; therefore for one (1) year of application a total of 16 applications were used for modeling the

turnip greens and mustard greens use.



## Table 1 2 . Dietary

- Based Clethodim EEC Values for Various Crops

Application Rate (crop) Dietary

- Based EECs (mg/kg

- diet)

Dietary Item

Short

Grass Tall

Grass Broadleaf

plants Fruits/pods/

seeds Arthropods

0.25 lb a.i./A @18 apps/7

- d interval

(annual app. 4.5 lb a.i./A) (fallow land, golf

course turf, non

- cropped areas; alfalfa) 425 195 239 27 167

0.25 lb a.i./A @ 9 apps/7

- d interval

(annual app. 2.25 lb a.i./A) (clover) 330 151 186 21 129

0.19 lb a.i./A @ 18 apps/7

- d interval (annual

app. 3.4 lb a.i./A) ( grass forage/ fodder/hay) 323 148 182 20 127

0.25 lb a.i./A @ 18 apps/14

- d interval

(annual app. 4.5 lb a.i./A) ( o rnamentals,

landscaped areas, non

- bearing food crops,

around buildings, bare soil, mulched areas) 246 113 138 15 96

0.25 lb a.i./A @ 4 apps/7

- d interval

(annual app. 1.0 lb a.i./A) ( s od farms

- only in

AL, FL, GA, NC, SC) 197 90 11 1 12 77

0.25 lb a.i./A @ 4 apps/14

- d interval

(annual app. 1.0 lb a.i./A) ( s pearmint) 166 76 93 10 65

0.125 lb a.i./A @ 16 apps/14

- d interval (annual

app. 2.0 lb a.i./A) ( i.e., turnip & mustard greens) 122 56 6 9 7.7 48

0.125 lb a.i./A @ 10 apps/14

- d interval

(annual app. 1.25 lb a.i./A) (r adishes) 116 53 65 7

. 3 45

## 30 Application Rate (crop) Dietary

- Based EECs (mg/kg

- diet)

Dietary Item

Short

Grass Tall

Grass Broadleaf

plants Fruits/pods/

seeds Arthropods

0.25 lb a.i./A @ 2 apps/7

- d interval

(annual app. 0.5 lb a.i./A) ( i.e., d ried beans,

Christmas trees, cotton, forest trees, peanuts,

potatoes, sainfoin, soybeans, sugar beets,

sunflowers, sweet potatoes, tomatoes, trefoil,

yams, lentils) 112 51 63 7 .0 44

0.125 lb a.i./A @ 8 apps/14

- d interval

(annual app. 1.0 lb a.i./A) (beets, b rassica

vegetables, leafy vegetables) 110 51 62 6.9 43

0.25 lb a.i./A @ 2 apps/14

- d interval

(annual app. 0.5 lb a.i./A) ( p eppermint) 105 48 59 6.6 41



## Table 1 3 . Avian Dose

- Based Clethodim Upper Bound EEC Values for Various Crops

Application Rate

(crop) Size

Class

(g) 1 

## Avian Dose

- Based EECs (mg/kg

- bw)

Dietary Item

Short

Grass Tall

Grass Broadleaf

plants Fruits/

pods Arthropods Seeds

0.25 lb a.i./A @18 apps/7

- d

interval (annual app. 4.5 lb

a.i./A) (fallow land, golf course

turf, non

- cropped areas; alfalfa) 20 484 222 272 30 190 6.7

0.25 lb a.i./A @ 9 apps/7

- d

interval (annual app. 2.25 lb

a.i./A) (clover) 20 376 172 212 24 147 5.2

0.19 lb a.i./A @ 18 apps/7

- d

interval (annual app. 3.4 lb

a.i./A) ( grass forage/ fodder/hay) 20 368 169 207 23 144 5.1

0.25 lb a.i./A @ 18 apps/14

- d

interval (annual app. 4.5 lb

a.i./A) (ornamentals, landscaped

areas, non

- bearing food crops,

around buildings, bare soil,

mulched areas) 20 280 128 158 18 110 3.9

0.25 lb a.i./A @ 4 apps/7

- d

interval (annual app. 1.0 lb

a.i./A) (sod farms

- only in AL,

FL, GA, NC, SC) 20 225 103 127 14 88 3.1

0.25 lb a.i./A @ 4 apps/14

- d

interval (annual app. 1.0 lb

a.i./A) (spearmint) 20 189 87 106 12 74 2.6

## 31 Application Rate

(crop) Size

Class

(g) 1 

## Avian Dose

- Based EECs (mg/kg

- bw)

Dietary Item

Short

Grass Tall

Grass Broadleaf

plants Fruits/

pods Arthropods Seeds

0.125 lb a.i./A @ 16 apps/14

- d

interval (annual app. 2.0 lb

a.i./A) ( i.e., turnip & mustard

greens) 20 139 64 78 8.7 55 1.9

0.125 lb a.i./A @ 10 apps/14

- d

interval (annual app. 1.25 lb

a.i./A) (radishes) 20 132 61 74 8.3 52 1.8

0.25 lb a.i./A @ 2 apps/7

- d

interval (annual app. 0.5 lb

a.i./A) ( i.e., dried beans,

Christmas trees, cotton, forest

trees, peanuts, potatoes, sainfoin,

soybeans, sugar beets,

sunflowers, sweet potatoes,

tomatoes, trefoil, yams, lentils) 20 128 59 72 8.0 50 1.8

0.125 lb a.i./A @ 8 apps/14

- d

interval (annual app. 1.0 lb

a.i./A) (beets, brassica

vegetables, leafy vegetables) 20 126 58 71 7.9 49 1.7

0.25 lb a.i./A @ 2 apps/14

- d

interval (annual app. 0.5 lb

a.i./A) (peppermint) 20 120 55 68 7.5 47 1.7

1 

### Adjusted LD 50 

### values (mg/kg

- bw): 20 g

– 1441; 100 g

– 1834; 1000 g

– 2591



## Table 1 4 . Mammalian Dose

- Based Clethodim Upper Bound EEC Values for Various Crops

Application Rate

(crop) Size

Class

(g) 1 

## Mammalian Dose

- Based EECs (mg/kg

- bw)

Dietary Item

Short

Grass Tall

Grass Broadleaf

plants Fruits/

pods Arthropods Seeds

0.25 lb a.i./A @18 apps/7

- d

interval (annual app. 4.5 lb a.i./A)

(fallow land, golf course turf, non

cropped areas; alfalfa) 15 405 186 228 25 159 5.6

35 280 128 158 18 110 3.9

0.25 lb a.i./A @ 9 apps/7

- d

interval (annual app. 2.25 lb

a.i./A) (clover) 15 315 144 177 20 123 4 .4

35 218 100 122 14 85 3 .0

0.19 lb a.i./A @ 18 apps/7

- d 15 308 141 173 19 121 4 .3

## 32 interval (annual app. 3.4 lb a.i./A)

( grass forage/ fodder/hay) 35 213 98 120 13 83 3 .0

0.25 lb a.i./A @ 18 apps/14

- d

interval (annual app. 4.5 lb a.i./A)

(ornamentals, landscaped areas,

non

- bearing food crops, around

buildings, bare soil, mulched

areas) 15 235 108 132 15 92 3 .3

35 162 74 91 10 64 2 .3

0.25 lb a.i./A @ 4 apps/7

- d

interval (annual app. 1.0 lb a.i./A)

(sod farms

- only in AL, FL, GA,

NC, SC) 15 188 86 106 12 74 2.6

35 130 60 73 8 51 1.8

0.25 lb a.i./A @ 4 apps/14

- d

interval (annual app. 1.0 lb a.i./A)

(spearmint) 15 158 73 89 10 62 2 .2

35 109 50 62 7 43 1.5

0.125 lb a.i./A @ 16 apps/14

- d

interval (annual app. 2.0 lb a.i./A)

( i.e., turnip & mustard greens) 15 117 53 66 7 46 1.6

35 81 37 45 5 32 1 .1

0.125 lb a.i./A @ 10 apps/14

- d

interval (annual app. 1.25 lb

a.i./A) (radishes) 15 111 51 62 7 43 1.5

35 77 35 43 5 30 1 .1

0.25 lb a.i./A @ 2 apps/7

- d

interval (annual app. 0.5 lb a.i./A)

( i.e., dried beans, Christmas trees,

cotton, forest trees, peanuts,

potatoes, sainfoin, soybeans, sugar

beets, sunflowers, sweet potatoes,

tomatoes, trefoil, yams, lentils) 15 107 49 60 7 42 1 .5

35 74 34 42 5 29 1 .0

0.125 lb a.i./A @ 8 apps/14

- d

interval (annual app. 1.0 lb a.i./A)

(beets, brassica vegetables, leafy

vegetables) 15 105 48 59 7 41 1 .5

35 73 33 41 5 28 1 .0

0.25 lb a.i./A @ 2 apps/14

- d

interval (annual app. 0.5 lb a.i./A)

(peppermint) 15 101 46 57 6 39 1.4

35 69 32 39 4 27 0.97

1 

## Adjusted LD 50 

## values (mg/kg

- bw): 15 g

– 2989; 35 g

– 2418; 1000 g

– 1046

2 

## Adjusted NOAEL values (mg/kg

- bw): 15 g

– 112.9; 35 g

– 90.7; 1000 g

– 39.2

## 33 3.3.2.2. Inhalation Modeling

Inhalation exposure of clethodim to birds and mammals from foliar application of clethodim is

not a potential route of exposure. STIR (v. 1.0) was used to calculate an upper bound estimate of

exposure using clethodim’s vapor pressure and molecular weight for vapor phase expo sure as

well as the maximum application rate and method of application for spray drift. STIR

incorporates results from several toxicity studies including acute oral and inhalation rat toxicity

endpoints [rat ( R. n orvegicus ) LD 50 

## (oral) and LD 50 

## (inhalatio n; 4

- hr exposure) of 1360 mg

a.i./kg

- bw (MRID 40974507) and >3.9 mg a.i./L (MRID 40974512 ), [bobwhite quail ( C.

virginianus ) LD 50 

## of >2,000 mg a.i./kg

- bw (MRID 40974525)]. Based on the results of the STIR

model, inhalation exposure alone was determined no t to be a potential pathway of concern for

avian or mammalian species on an acute basis. Refer to Appendix E for additional details on the

inhalation modeling for clethodim.

3.3.2.3. Drinking Water Modeling

Drinking water alone is not a potential route of exposure of clethodim to birds and mammals.

SIP (v. 1.0) was used to calculate an upper bound estimate of exposure using daily water intake

rates (Flux

water 

## ) for birds (20g bird = 0.162 L) and mammals (1000 g mammal = 0.172 L), and

the solubility in water at 25°C. SIP incorporates the results from several toxicity studies include

acute and chronic avian and mammalian endpoints [bobwhite quail ( C. virginianus ) LD 50 

## of

>2,000 mg a.i./kg

- bw (MRID 40974525 ); rat ( R. n orvegicus ) LD 50 

## (oral) 1360 mg a.i./kg

- bw

(MRID 40974507) ; mallard duck ( A. platyrhynchos ) NOAEC of 833 mg a.i./kg

- diet (MRID

41030205); rat NOAEL = 51 mg a.i./kg

- bw (MRID 41030120)]. Based on the r esults of the SIP

model, drinking water exposure alone was determined not to be a potential pathway of concern

for avian or mammalian species on an acute and/or chronic basis. Refer to Appendix E for

additional details on the drinking water exposure model ing for clethodim.

3.3.2.4. Plants Modeling

Terrestrial Plants

Terrestrial exposure estimates for plant risk assessment w as derived using the T errPlant model

(version 1. 2

. 2 , 05/2 8 /2013). TerrPlant provides estimates of exposure to terrestrial plants from a

single pesticide application, and pesticide EECs in runoff and drift are estimated. This model

does not consider exposures to plants from multiple pesticide applications. Exposure

ca lculations are based on a pesticide’s water solubility and the amount of pesticide present on the

surface soil within the first inch of depth. For dry areas, the loading of pesticide active

ingredient from runoff to an adjacent non

- target area is assumed to occur from one acre of

treatment to one acre of non

- target area; for semi

- aquatic (wetland) areas, runoff is considered to

occur from a larger source area with active ingredient loading originating from 10 acres of

treated area to a single area of non

- t arget wetland. Default spray drift assumptions are 1% for

ground applications, and 5% for aerial, airblast, forced air, and chemigation applications. The

input parameters and EECs for terrestrial and semi

- aquatic plants exposed to a single application

of clethodim at labeled rates are presented in Table 15

. Example input/outputs from TerrPlant

for clethodim can be found in Appendix B

.

## 34 Table 15 . TerrPlant Inputs and Resulting EECs for Plants Inhabiting Dry and Semi

aquatic Areas Exposed to Clethodim via Runoff and Drift 1



## Use App

.

rate

(lbs

a.i./A) Application

method Drift

Value

(%) Spray drift

EEC

(lbs a.i./A) Dry area

EEC

(lbs a.i./A) Semi

- aquatic

area EEC

(lbs a.i./A)

Ma ximum single app. rate (aerial)

- fallow land, golf course turf, non

cropped areas, alfalfa, clover, dried

beans, Christmas trees, cotton,

forest trees, peanuts, potatoes,

sainfoin, soybeans, sugar beets,

sunflowers, sweet potatoes,

tomatoes, trefoil, yams, mint,

lentils, sod farms ; (chemigation)

- garlic and onions 0.25 Foliar

–

A e rial and

chemigation 5 0.0125 0.0175 0.0625

Maximum single app. rate (ground)

- Ornamentals, landscaped areas,

non

- bearing food crops, around

buildings, bare soil, mulched areas 0.25 Foliar

– ground 1 0.00 3 0.00 8 0.05 3

Mid app. rate

- turnip greens,

mustard greens, herbs, beets,

brassica vegetables, carrots,

cranberries, cucurbit vegetables,

fruiting vegetables, leafy

vegetables, strawberries, radishes,

tree fruits, tree nuts, asparagus,

hops, safflower, sesame, artichokes,

bushberries including cranb erries,

caneberries, peaches, flax,

meadowfarm, seeds, succulent

beans, legume vegetables, dried and

succulent peas 0.125 Foliar

-

A e rial 5 0.006 0.00 9 0.031

Mid app. rate

- sage, kenaf 0.125 Foliar

-

Ground 1 0.001 0.004 0.026

Second lowest app. rate

- c anola 0.10 Foliar

–

A e rial 5 0.005 0.007 0.025

Lowest app. rate

- c orn (field) 0.045 Foliar

–

A e rial 5 0.002 0.003 0.011

1 

### The TerrPlant model considers only exposures to plants from single pesticide applications.



## 3.4. Ecological Effects Characterization

The ecological effects characterization for clethodim is based upon registrant

- submitted toxicity

data for the TGAI and specified formulations of the parent clethodim

. There is no available

ecotoxicity data for the degradates of clethodim, and due to the similarity of the structures of

clethodim (parent) and the degradates, are assumed to be of equal toxicity to the parent. A

summary of the available ecological toxici ty data (including review classifications and

associated deficiencies) for clethodim is in Appendix C

. Th e data is summarized briefly in

## 35 Sections 3.4.1 to 3.4. 6 . The bobwhite quail avian reproduction study previously identified as

supplemental was recently downgraded to unacceptable/invalid due to a high rate of control

mortality and general concern for the health of the test organisms. Numerous studies includi ng

estuarine/marine acute and chronic studies have been received since the Problem Formulation

was issued; the results of these studies are described briefly in the following sections. In

addition, clethodim was identified among the second list of chemica ls identified in the endocrine

disruptor screening program, and is discussed further in Section 3.4.6

.

The results of the review of the Ecological Incident Information System (EIIS) are described in

Section 3.5 . A search of the ECOTOXicology database in July 2012 yielded two non

- vascular

aquatic plant toxicity studies with more sensitive toxicity endpoints than the registrant

- submitted

guideline studies described below ( Section 3.4.4.1 )

.

3.4.1. Aquatic Animals

A summary of the most sensitive aquatic animal tox icity data for clethodim, based on Agency

review of all submitted data, is provided in Table 16 , and discussed further in Sections 3.4.1.1

through 3.4.1.2

. The full summary of the aquatic toxicity data for clethodim is found in

Appendix C

. Studies conducted with technical grade clethodim were submitted for the

following aquatic animals: f ive fish [rainbow trout ( Oncorhynchus mykiss ), bluegill sunfish

( Lepomis macrochirus ), zebra fish ( Danio rerio ), and fathead minnow ( Pimephales promelas )

, (s heepsh ead m innow

, Cyprinodon variegates ) ] ; one estuarine/marine mollusk (Eastern oyster,

Crassostrea virginica ); and

, one estuarine/marine invertebrate

- mysid shrimp ( Americamysis

bahia)

. For t he freshwater invertebrate ( Daphnia magna ) the available acute toxi city study was

conducted with a clethodim end use product (Select 2EC) ; as the study conducted with the

t echnical grade material was an unacceptable study

. The available toxicity data indicate that

clethodim TGAI ranges from slightly to practically non

- toxic to freshwater and estuarine/marine

fish and invertebrates, and moderately toxic to estuarine/marine mollusks , on an acute exposure

basis . Formulated clethodim is slightly toxic to freshwater invertebrates, on an acute ex posure

basis. Chronic toxicity data is available for only freshwater aquatic organisms, and therefore, in

the absence of data will be used as a conservative estimate of risks to estuarine/marine aquatic

organisms resulting from chronic exposure to clethod im.

Table 16. Summary of the Most Sensitive Acute and Chronic Toxicity Data for Aquatic

Animals Exposed to Clethodim

Species Test

Material Acute Toxicity Chronic Toxicity 1 

## s

LC 50 

## /EC 50 

## (mg a.i./L)

(Toxicity

Classification) MRID

(Study

Classification) NOAEC/

LOAEC

(mg a.i./L)

(Endpoints) MRID

(Study

Classification)

Rainbow trout

( O

. mykiss ) TGAI

(83.3%) 24.4

(slightly toxic) 40974528

(Acceptable) 0.002 * ACR derived

NOAEC *

Fathead

minnow

( P

. promelas ) TGAI

(95.4%) 110

(practically

non

- toxic) 48417002

(Acceptable) 0.010/0.031

(reduced survival;

effects on reproduction

were not measured) 48104303

( Supplemental )

## 36 Species Test

Material Acute Toxicity Chronic Toxicity 1 

## s

LC 50 

## /EC 50 

## (mg a.i./L)

(Toxicity

Classification) MRID

(Study

Classification) NOAEC/

LOAEC

(mg a.i./L)

(Endpoints) MRID

(Study

Classification)

Waterflea

( D

. magna ) Acute:

EP (25.6%)

Chronic:

TGAI

( 95.7%) 20.2

(slightly toxic) 41685101

(Acceptable) 0.94/3.0

( Reduction in

reproduction

(offspring per female)

& total length of

surviving daphnids) 48104305

(Supplemental)

Eastern oyster

( C

. virginica ) TGAI

(95.4%) 5.3

(moderately

toxic) 48563001

(Supplemental) -- --

ND = No data;

-- = Not applicable

* Rainbow trout was the most sensitive acute fish value; therefore a N OAEC was derived using an ACR of available

acute and chronic toxicity data for the fathead minnow = [(Fathead LC50/ NOAEC) = ACR; (RT LC50/ACR) =

0.002 mg a.i./L]

1 

### No acceptable estuarine/marine fish or invertebrate chronic toxicity data are available for clethodim ; therefore the

estimated freshwater fish and aquatic invertebrate NOAEC value s for rainbow trout and daphnids were used as a

conservative estimate s of potential toxici ty to estuarine/marine fish and invertebrates (NOAEC = 0.002 mg a.i./L

and 0.94 ) , respectively

.



## 3.4.1.1. Fish

A total of six fish toxicity studies are available to evaluate the acute effects of clethodim

exposure. Observed sublethal effects included lethargy, su rfacing, lying on the bottom, a

swollen abdomen, loss of equilibrium, gulping air, and quiescence. The reported 96

- hr LC 50 

## values fall in the range of 24.4

- 133 mg a.i./L; therefore clethodim technical ranges from slightly

to practically non

- toxic to fish on an acute exposure basis ( Appendix C )

. Although an

estuarine/marine fish toxicity study is available for the sheepshead minnow , t he acute toxicity

value for rainbow trout (LC 50 

## = 24.4 mg a.i./L; MRID 40974528) will be used as a proxy to

estimate acute r isk to fish in this risk assessment . T his endpoint is protective for all species of

fish ( both freshwater and estuarine/marine)

.

The re is only one study available for assessing the effects of chronic exposure to fish , a fathead

minnow with clethodim technical (TGAI; 95.7%; MRID 48104303 )

. In absence of

estuarine/marine chronic toxicity data, as in the case with the acute toxicity to fish, the

freshwater fish data will be used to estimate the potential toxicity to estuarine/marine fish on a

chronic exposure basis. T he fathead minnow study was classified as supplemental and does not

fulfill guideline requirements due to numerous deviations ( i.e., no reproductive endpoints ( time

to hatch, hatchling success, and post

- hatch survival ) were me asured; the dilution water was

dechlorinated tap water and chlorine was not measured; and the actual concentrations were not

measured)

. The NOAEC and LOAEC , based on mortality, were determined to be 0.01 mg/L and

0.031 mg/L, respectively. R ainbow trout i s the most sensitive fish based on acute exposure to

clethodim, and therefore, perhaps rainbow trout may also be more sensitive to clethodim on a

chronic basis. Therefore, in order to account for the potential difference in toxicity to other fish

species on a chronic exposure basis, an acute to chronic ratio (ACR) was used to estimate a

NOAEC value relative to an increase in sensitivity on an acute exposure basis. Using the acute

## 37 and chronic toxicity endpoints for fathead minnow, the derived ACR was calcu lated to be 11000

[FH LC 50 

## (110 mg a.i./L) / FH NOAEC (0.01 mg/L)]. The estimated NOAEC value was derived

using the acute toxicity endpoint for rainbow trout and the fathead minnow (FH) ACR [RT LC 50 

## (24.4 mg a.i./L) / FH ACR (11000)] = 0.002 mg a.i./L. T he estimated chronic toxicity value for

rainbow trout (ACR derived NOAEC = 0.002 mg a.i./L) will be used to estimate chronic risk to

fish in this risk assessment.

It should be noted that t here are major uncertainties associated with the chronic fish en dpoint that

is used in this risk assessment. First, t he available fathead minnow toxicity study NOAEC

endpoint is based on mortality, and not the typical sublethal (growth or reproduction) endpoints

that are used for chronic exposure s , and could be an und erestimation of risk to fish

. Second , the

chronic toxicity value that is being used is based on an ACR which relies on an extrapolation

among species. However, this is the best available informat ion to evaluate chronic risk to fish in

this risk assessment

.

3.4.1.2. Aquatic Invertebrates

The acute toxicity studies for clethodim and aquatic invertebrates resulted in the following:

freshwater invertebrate ( water flea ) EC 50 

## value of 20.2 mg a.i./L ( EP, 25.6% a.i.; MRID

41685101) and estuarine /marine invertebrate (mollusk, Eastern oyster ) EC 50 

## (shell deposition)

value of 5.3 mg a.i./L ( TGAI, 95.4 % a.i.; MRID 48563001 ) ; and estuar ine

- marine invertebrate

(shrimp, mysid) EC 50 

## value 33 mg a.i./L (TGAI 95.4% a.i.; MRID 48417001)

. Therefore,

cletho dim is classified as moderately to slightly toxic to freshwater and estuarine/marine

invertebrates on an acute exposure basis. The daphnid and mysid studies were classified as

acceptable and the oyster study was classified as supplemental. S ublethal effe cts were only

observed in the estuarine/marine invertebrate (mysid) acute toxicity test and included lethargy,

surfacing, and lying on the bottom of the chamber. The acute toxicity value for daphnids (EC 50 

## = 20.2 mg a.i./L) and the acute toxicity value for oysters (EC 50 

## = 5.3 mg a.i./L) will be used to

estimate acute risk to freshwater and estuarine/marine invertebrates in this risk assessment,

respectively.

A chronic study was available for clethodim an d freshwater invertebrates ( D. magna ) that

resulted in NOAEC and LOAEC values of 0.93 mg a.i./L and 3.0 mg a.i./L, respectively, based

on reduction in reproduction (offspring per female) and total length of surviving daphnids

(MRID 48104305 ) . Survival was also significantly decreased; however it was not the most

sensitive endpoint

. In addition, based on visual observations of the data, there also appears to be

a significant delay in time to first brood release. There are currently no acceptable

estuarine /marine chronic invertebrate toxicity data available for clethodim; therefore, the

freshwater aquatic invertebrate NOAEC value for daphnids will be used as a conservative

estimate of potential toxicity to estuarine/marine invertebrates , t his endpoint is pr otective of

aqu a tic invertebrates (both freshwater and estuarine/marine).

For sediment

- dwelling organisms, there is some uncertainty with the lack of toxicity data.

Although a whole sediment toxicity study could potentially be triggered ( log Kow ≥3, the

anaerobic aquatic metabolism half

- life of clethodim is 233 days ), clethodim is rapidly

biodegraded in aerobic conditions (half

- lives of 1

- 7 days) typically to more polar degradates that

## 38 are expected to be easier to metabolize and to have lo wer K OW 

## values than clethodim. However,

based on the variation of degradation between the anaerobic and aerobic environments and the

lack of aerobic aquatic metabolism data, there is some uncertainty with toxicity to sediment

dwelling organisms. Addition al data would decrease the uncertainty of risk to sediment

dwelling aquatic organisms.

3.4.2. Aquatic Plants

A summary of the most sensitive aquatic plant toxicity data for clethodim, based on Agency

review of all submitted data (registrant

- submitted and open literature) , is provided in Table 17

, and discussed further in Sections 3.4.2.1 through 3.4.2.2

. The full summary of the aquatic plant

toxicity data for clethodim is found in Appendix C

. The mode of action of clethodim is very

specific to terrestrial gra ss s pecies , and aquatic plants are not as sensitive as terrestrial grass

species.

Table 17. Summary of the Most Sensitive Toxicity Data for Aquatic Plants Exposed to

Clethodim

Species Test

Material Endpoint

(mg a.i./L) Effect

(MRID; Study Classification)

Marine Diatom

( Skeletonema costatum ) EP

(25.6%) 120 hr EC 50 

## = 8.6

120 hr NOAEC = 5.4 Inhibition of growth rate based on cell

counts after 5 days (120 hours).

(42029704; Acceptable)

Green algae

( Raphidocelis subcapitata ) EP

(12%) 96 hr EC 50 

## = 2.7 Inhibition in growth rate based on cell

counts after 96 hours.

( E083543; Ma et al ., 2006; Qualitative)

Duckweed

( Lemna gibba ) TGAI

(82.4%) 14

- d EC 50 

## = 1.34

14

- d NOAEC = 0.37 Percent inhibition based on mean frond

counts on day 14

. (42029701; Acceptable)



## 3.4.2.1. Non

- Vascular Plants

Five studies were submitted for aquatic non

- vascular plants; t wo studies were submitted for

green algae ( S

. capricornutum ) using both clethodim technical (MRID 4 1685106) and an end use

product (MRID 42029703) , and one study each using a clethodim end

- use product (Select 2.0

EC; 25.6% a.i.) for blue

- green algae ( A

. flos

- aquae ; MRID 42029705), a freshwater diatom ( N

. pelliculosa ; MRID 42029706 ) and a marine diatom ( S

. costatum ; MRID 4202970 4 )

. The 120 hr

EC 50 

## for non

- vascular aquatic pla nts using a clethodim end

- use product ranged from 8.6 mg

a.i./L to 19.5 mg a.i./L, with NOAEC values ranging from 5.4 mg a.i./L to 11.4 mg a.i./L. The

most sensitive registrant submitted non

- vascular aquatic plant was the marine diatom with EC 50



## and NOAEC values of 8.6 mg a.i./L and 5.4 mg a.i./L, respectively, based on inhibition of

growth rate.

In addition to the available registrant submitted studies for non

- vascular aquatic plants, there

were two open literature studies that were identified in the E COTOXicology database. These

two studies were reviewed as it was indicated that there were more sensitive endpoints for non

vascular aquatic plants (the green algae C

. vulgaris and R

. subcapitata ; E065938; Ma et al ., 2002

and E083543; Ma et al ., 2006, respectively ) with 96 hr EC 50 

## values of 4.6 mg a.i./L and 2.7 mg

## 39 a.i./L, respectively. Based on the review of the available data, both of these studies were

classified to be used qualitatively within the risk assessment. The refore, the results for the op en

literature studies, although more sensitive, will not be used to calculate RQ values, but they will

be incorporated into the risk characterization of the risks to non

- vascular aquatic plants.

3.4.2.2. Vascular Plants

Two vascular aquatic plant toxicity studies are available for clethodim on duckweed ( Lemna

gibba ), one was conducted with technical grade material (82.4% a.i. ; MRID 42029701 ) and the

second used a clethodim end

- use product (Select 2.0 EC; 25.6% a.i. ; MRID 42029702 ). The 14

- day EC 50 

## and NOA EC values were 1.34 mg a.i./L and 0.37 mg a.i./L, respectively using

technical grade material, based on mean frond counts, which was more sensitive than the

endpoint obtained from the end

- use product toxicity study

.

3.4.3. Terrestrial Animals

A summary of the most sensitive terrestrial animal toxicity data for clethodim, based on Agency

review of all submitted data, is provided in Table 1 8 , and discussed further in Sections 3.4. 3 .1

through 3.4. 3

. 3 . The full summary of the terrestrial animal toxicity data for clethodim is found

in Appendix C

. Studies conducted with technical grade clethodim were submitted for the

following terrestrial animals: two birds [ (Northern Bobwhite Quail

, Colinus virginianus ) , and

( Mallard Duck

, Anas platyrhynchos ) ]; one mammal (laboratory rat; ( Rattus norvegicus ) . The

honey bee, ( Apis mellifera ) acute toxicity st udy was conducted with a clethodim end use product

. The available toxicity data indicate that clethodim TGAI ranges from slightly to practically non

toxic t o mammals and birds , on an acute exposure basis. Formulated clethodim is practically

non

- toxic to honey bees (terrestrial invertebrates ) , on an acute exposure basis. The available

avian and mammalian reproduction studies for clethodim do not show any rep roductive effects

resulting from chronic exposure to clethodim.

Table 18. Summary of the Most Sensitive Acute and Chronic Toxicity Data for Terrestrial

Animal s Exposed to Clethodim

Species Test

Material Acute Toxicity Chronic Toxicity

LD 50 

## (mg a.i. /kg bw)

(Toxicity

Classification) LC 50 

## (mg a. i ./kg

diet (ppm))

(Toxicity

Classification) MRID

(Study

Classification) NOAEC/

LOAEC

(mg a. i ./kg diet

(ppm))

(Endpoints) MRID

(Study

Classification)

Bobwhite

Quail

( C

. virginianus ) TGAI

(82%) > 2000

(practically

non

- toxic) > 4270

(practically

non

- toxic) 40974525

(Acceptable)

&

40974526

(Acceptable) N A 1 

## N A

Mallard Duck

( A

. platyrhynchos ) TGAI

(Acute: 82%)

(Chronic:

83.3%) ND > 3978

(practically

non

- toxic) 40974527

(Acceptable) 833/ >833

(N o effects) 41030205

(Acceptable)

## 40 Species Test

Material Acute Toxicity Chronic Toxicity

LD 50 

## (mg a.i. /kg bw)

(Toxicity

Classification) LC 50 

## (mg a. i ./kg

diet (ppm))

(Toxicity

Classification) MRID

(Study

Classification) NOAEC/

LOAEC

(mg a. i ./kg diet

(ppm))

(Endpoints) MRID

(Study

Classification)

Laboratory rat

( R

. norvegicus ) TGAI

(Acute:

83.3%)

(Chronic:

82.3%) 1360

(slightly

toxic) -- 40974507

(Acceptable) 500/2500

(51/263 mg

a.i./kg

- bw/day)

( d ecreased body

weight & food

consumption in

parental

organisms, NO

reproductive

effects) 41030120

(Acceptable)

Honey Bee

( A

. mellifera ) EP

(26% a.i.) >100 μ g

a.i./bee



## (p ractically

non

- toxic ) 2 

## -- 41685107

( Acceptable ) -- --

N D = No Data; NA = Not Available ;

-- = N ot applicable

1 

### A high rate of adult mortality in both control and test subjects were not adequately e xplained. This study

was recently downgraded to unacceptable/invalid.

2 

### Based on classification in paper by Atkins, E.L. Division of Agricultural Scien ces, University of California. MRID

44038201. A LD 50 

### of >11 μg/bee was classified as p ractically non

- toxic.



## 3.4.3.1. Birds

Based on the 14

- day non

- definitive LD 50 

## value for the northern bobwhite quail ( C. virginianus )

of >2000 mg a.i./kg

- bw clethodim is c lassifie d as practically non

- toxic to avian species on an

acute oral

- exposure basis (MRID 40974525 ). However, overt signs of toxicity ( i.e., lethargy,

wing droop and ruffled appearance) and a reduction of body weight gain were observed in the

1650 mg a.i./kg

- bw co ncentration, but not at any lower test levels ( i.e., ≤ 1250 mg a.i./kg

- bw )

. Based on the 8

- day non

- definitive LC 50 

## value for bobwhite quail of >4,270 mg a.i./kg diet

(MRID 40974526), and mallard ducks of >3,978 mg a.i./kg diet (MRID 40974527), clethodim is

classified as slightly to practically non

- toxic to avian species on a subacute dietary exposure

basis. There is only one acceptable avian reproduction study available for clethodim: a study

using mallard duck ( A. platyrhynchos ; MRID 41030205 ); the bobwhite quail study was

downgraded

. For the mallard duck study, there were no observed effects (mortality or

reproductive), and t he NOAEC and LOAEC values for the mallard duck study were 833 and

>833 mg a.i./kg diet , respectively

. The chronic toxicity v alue for mallard duck (833 mg a.i./kg

diet) will be used to estimate chronic risk to birds in this assessment.

3.4.3.2. Mammals

Based on the acute oral LD 50 

## value of 1,360 mg a.i./kg

- bw for the laboratory rat ( R

. norvegicus )

, clethodim is characterized as slightly toxic to mammalian species on an acute oral

- exposure

basis (MRID 40974507 )

. A 2

- generation study was performed with clethodim technical in rats.

The NOAEC and LOAEC values were 500 and 2500 ppm (51 and 263 mg/kg

- bw /day),

## 41 respectively, based on a decrease in body weight and food consumption in parent s in both

generations (MRID 41030120)

. T here were no reproductive effects reported in the mammalian

reproductive toxicity study . The acute oral toxicity value (LD 50 

## = 1,360 mg a.i./kg

- bw) and

chronic toxicity value (NOAEC = 500 ppm (51 mg/kg/day)) for rats will be used to estimate

acute and chronic risk to mammals in this assessment.

3.4.3.3. Terrestrial Invertebrates

The re is one acute honey bee contact study available for cl ethodim. The young adult honey bee

( A. mellifera ) acute contact study reported a LD 50 

## of >100 μg a.i./bee (MRID 41685107) using

an end

- use product of clethodim (26% a.i.) ; there were no mortalities or sublethal effects at this

dose

. Based on the acute contact honeybee study, clethodim is classified as practically non

toxic.

3.4.4. Terrestrial Plants

A summary of the most sensitive aquatic plant toxicity data for clethodim, based on Agency

review of all submitted data (registrant

- submitte d and open literature), is provided in Table 1 9

, and discussed further in Sections 3.4.4 .1 through 3.4. 4 .2

. The full summary of the terrestrial

plant toxicity data for clethodim is found in Appendix C

. The mode of action of clethodim is

very specific to g rasses ( inhibiting the acetyl

- coenzyme A carboxylase (ACCase) enzyme of

grass species ), and the m onocot plants , specifically, the members of the Poaceae family were the

most sensitive terrestrial plant species to clethodim exposure. No effect s were observ ed in dicot

plant species when tested at the highest single application rate (0.25 lbs a.i./A).

Table 19. Summary of the Most Sensitive Toxicity Data for Terrestrial Plant s Exposed to

Clethodim

Species /

Test material EC 25 

## (lb a.i./acre) NOAEC

(lb a.i./acre) Most Sensitive

Endpoint MRID

( Study

Classification )

Seedling Emergence

All Dicots tested

EP (82.4%) > 0.25 ≥ 0.25 No effects at max.

app . rate 41685102

(Acceptable)

Monocots

Oat ( Aveana sativa )

EP (82.4%) 0.0076 0.0004*

(EC 05 

## ) Plant height 41685104

(Acceptable)

Onion ( Allium cepa )

EP (82.4%) > 0.25 ≥ 0.25 

## No effects 41685104

(Acceptable)

Vegetative Vigor

All Dicots tested

EP (82.4%) > 0.25 ≥ 0.25 No effects at max.

app . rate 41685103

(Acceptable)

Monocots

Rye grass ( Lolium perenne )

EP (82.4%) 0.003 0.002 *

(EC 05 

## ) Dry weight 41685105

( Acceptable )

Onion ( A

. cepa )

EP (82.4%) > 0.25 ≥ 0.25 

## No effects 41685105

(Acceptable)

ND = No Data; NA = Not Available;

-- = Not applicable

* EC 05 

### is used when a NOAEC could not be calculated or NOAEC is higher than the EC 25

## 42 3.4.4.1. Dicot yledon plants

Based on the results of the submitted Tier I seedling emergence and vegetative vigor toxicity

test s for clethodim using an end

- use product (SELECT; 82.4% a.i.; MRID 41685102 and

41685103, respectively), it was determined that a ll dicot species that were tested demonstrated

no significant effects resulting from clethodim application at the maximum singl e application

rate

.

3.4.4.2. Monocotyledon plants

For monocot plants effects were observed in both the seedling emergence and vegetative vigor

toxicity tests for clethodim using an end

- use product (SELECT; 82.4% a.i.; MRID 41685104 and

41685105, respectively) f or all monocot species tested, except for onion. No significant effects

were observed for onions exposed to clethodim in either the seedling emergence or vegetative

vigor toxicity tests. One note is that the three of the four monocot plant species that s howed

effects (corn, perennial ryegrass, and oat s ) all belong to f amily Poaceae , the grass family (which

is the same family as the target species of clethodim) , whereas onion (which showed no effects)

is in a different monocot family, f amily Liliaceae. Ho wever, there are numerous other monocot

families that are not represented, but there is evidence to suggest based on the mode of action of

clethodim, and the mechanism of selectivity within grass species for the ACCase enzyme site of

action

, suggests that there are differential sensitivity between grass species, and species (Hess,

1997). For seedling emergence the most sensitive parameter was plant height and the most

sensitive monocot species was oat s ( A

. sativa , MRID 41685104 ). Oat had an EC 25 

## value of

0 .0076 lbs a.i./A and NOAEC (EC 05 

## ) value of 0.0004 lbs a.i./A (MRID 41685104 ). For

vegetative vigor the most sensitive parameter was dry weight and the most sensitive monocot

species was peren n ial r y e grass ( L

. perenne , MRID 41685105 ) . Ryegrass had an EC 25 

## value of

0.003 lbs a.i./A and NOAEC (EC 05 

## ) value of 0.0023 lbs a.i./A (MRID 41685105). The EC 25 

## was lower than the NOAEC; therefore, the EC 05 

## was calculated and used in place of a NOAEC

value for monocot plants exposed to clethodim. These endpoints fo r oat s and perennial ryegrass

for seedling emergence and vegetative vigor, respectively, will be used to assess risk to monocot

plants in this assessment.

3.4.5. Degradate Toxicity Data

There is no eco toxicity data for any of the degradates of clethodim , spe cifically for the clethodim

sulfone and clethodim sulfoxide degradates

. For the purpose of this assessment, the degradates

(clethodim sulfoxide and clethodim sulfone ) containing the hexenone moiety are assumed to

have the same toxicity as the parent compo und (USEPA, 2008) because the toxic moiety of the

active ingredient appears to potentially be intact.

3.4.6. Endocrine Disruptor Screening Program

As required by FIFRA and FFDCA, EPA reviews numerous studies to assess potential adverse

outcomes from exposure to chemicals. Collectively, these studies include acute, subchronic and

chronic toxicity, including assessments of carcinogenicity, neurotoxici ty, developmental,

reproductive, and general or systemic toxicity. These studies include endpoints which may be

## 43 susceptible to endocrine influence, including effects on endocrine target organ histopathology,

organ weights, estrus cyclicity, sexual maturati on, fertility, pregnancy rates, reproductive loss,

and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and

chronic studies that assess growth, developmental and reproductive effects in different

taxonomic groups. As part of the Preliminary Problem Formulation for Registration Review (DP

Barcode 349758)

, EPA reviewed these data and selected the most sensitive endpoints for

relevant risk assessment scenarios from the existing hazard database. However, as required by

FF DCA section 408(p), clethodim is subject to the endocrine screening part of the Endocrine

Disruptor Screening Program (EDSP).

EPA has developed the EDSP to determine whether certain substances (including pesticide

active and other ingredients) may have a n effect in humans or wildlife similar to an effect

produced by a “naturally occurring estrogen, or other such endocrine effects as the Administrator

may designate.” The EDSP employs a two

- tiered approach to making the statutorily required

determinations. Tier 1 consists of a battery of 11 screening assays to identify the potential of a

chemical substance to interact with the estrogen, androgen, or thyroid (E, A, or T) hormonal

systems. Chemicals that go through Tier 1 screening and are found to have the potential to

interact with E, A, or T hormonal systems will proceed to the next stage of the EDSP where EPA

will determine which, if any, of the Tier 2 tests are necessary based on the available data. Tier 2

testing is designed to identify any adverse endo crine

- related effects caused by the substance, and

establish a dose

- response relationship between the dose and the E, A, or T effect.

Under FFDCA section 408(p), the Agency must screen all pesticide chemicals. Between

October 2009 and February 2010, EPA issued test orders/data call

- ins for the first group of 67

chemicals, which contains 58 pesticide active ingredients and 9 inert ingredients. A second list

of chemicals identified for EDSP screening was published on June 14, 2013 2 

## and includes some

pesti cides scheduled for registration review and chemicals found in water

. Neither of these lists

should be construed as a list of known or likely endocrine disruptors.

Clethodim is on List 2. List 2 represents the next set of chemicals for which EPA intends to issue

test orders/da ta call

- ins in the near future. For further information on the status of the EDSP, the

policies and procedures, the lists of chemicals, future lists, the test guidelines and the Tier 1

screening battery, please visit our website. 3



## 3.5. Review of Incident Data

Reviews of the Ecological Incident Information System (EIIS, version 2.1), the Avian Incident

Monitoring System (AIMS) 4 

## , and the EPA Incident Data System (IDS) were conducted on June

6, 2013. There are two incidents involving clethodim and terrestrial plants that were reported in

the EIIS database (I002969

- 058 and I022217

- 034 ). Both of these incident s w ere of

undetermined legality and clethodim was listed as a possible cause of the alleged dam age to the

respective crops; cotton after the use of Select 2EC (the active ingredient is clethodim) (I002969

-

2 

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

- HQ

- OPPT

- 2009

- 0477

- 0074 for the final second list of

chemicals.

3 

### http://www.epa.gov/endo/

4 

### http://www.abcbirds.org/abcprograms/policy/pesticides/aims/aims/index.cfm

## 44 058 ), and soybean after the product Ignite 280 SL (a.i. glufosinate

- ammonium) and Select (a.i.

clethodim) were applied (I022217

- 034 ). Cotton and soybeans are dicots, and based on the

available toxicity data for clethodim, these species would not be expect ed to be sensitive to

clethodim as it is an herbicide that targets monocot species. Although very little information is

available for I002969

- 058 , potential cotton crop injury, tissue testing was completed to

determine that Select (clethodim a.i.) was not likely the cause of the injury. It is uncle ar what, or

if another pesticide was involved at all . For I022217

- 034, the damage to the soybean cro p was

likely the result of tank contamination; however, it is not clear which chemical the tank

contaminated with. The number of reported incidences may only reflect a small proportion of

actual incidents that occurred, uncertainties and animal behavior m ay influence the number of

observed deaths as sociated with pesticide usage. There are no reported incidents for clethodim

in the AIMS database. There are 2 reported minor plant incidents in IDS database reported in

2000 and 2006 (010131

- 3 and 018521

- 3, r espectively) for the Select 2EC formulation of

clethodim. T he lack of reported incidences should not be construed as the absence of incidents.

Incident reports for non

- target organisms typically provide information only on mortality events

and plant dama ge. Sublethal effects in organisms such as abnormal behavior, reduced growth

and /or impaired reproduction are rarely reported, except for phytotoxic effects in terrestrial

plants.

4. RISK ESTIMATION

For this preliminary assessment of c lethodim , the dete rministic risk quotient (RQ) method wa s

used to provide a metric of potential risks. The RQ is a comparison of exposure estimates to

toxicity endpoints. The resulting RQs are compared to the Agency’s risk levels of concern

(LOC )

, which are the Agency’s i nterpretive policy such that when risk LOCs for listed and/or

non

- listed species, are exceeded, the need for regulatory action may be considered. These

criteria are used to indicate when the use of a pesticide, as directed on the label, has the potential

to cause adverse effects to non

- target organisms.

4.1. Non

- target Aquatic Organisms

Clethodim is classified as slightly to practically non

- toxic to fish and aquatic invertebrates on an

acute exposure basis. In the absence of chronic estuarine/marine fish and invertebrate toxicity

data, the freshwater fish and aquatic invertebrate toxicity data will be used to evaluate the

chronic risk to fish and aquatic invertebrates from exposure to clethodim. The RQ values for the

use site with highest EECs (alfalfa) and using the most sensitive acute and chronic toxicity

values for fish and aquatic invertebrates are presented in Table 20 , and aquatic plant values are

presented in Table 21

.

RQs exceeded the chronic risk LOC for listed and non

- listed fish , only (RQ ≥ 1 .0 ) . There were no

other risk LOC exceedances for aquatic organisms, i.e. , no chronic listed or non

- listed species

L OC exceedances for aquatic invertebrates (freshwater or estuarine/marine) (RQ < 1 .0 ) , no acute

listed species LOC exceedances for aqu atic invert ebrates and /or fish ( RQ<0.05) , and no risk

LOC exceedances for aquatic plants (RQ < 1 .0 ) ( Table 20 and Table 21 )

.

## 45 RQ values for use sites other than alfalfa are also presented in Table 20 to explore chronic risk

LOC exceed a nces

. The chronic risk LOC for fish is exceeded by all modeled uses of clethodim,

including those expected to produce the lowe st exposure estimates ( e.g. , hops and corn). Based

on these results, all use sites of clethodim that are currently registered ( i.e.

, all 67 uses and use

gr oups in Table 3 ) result in chronic listed and non

- listed species LOC exceedances to fish

. Risk

to fish, aquatic invertebrates, and aquatic plants are discussed further in the Risk Description

section.

Table 20 . Maximum Clethodim RQ Values for Aquatic Animals A



## Use Site Taxa EECs (μg a.i./L) RQ

Peak Chronic

(21

- d/60

- d) Acute B 

## Chronic C



## (60

- d for fish/21

- d for

invertebrates)

Aquatic Invertebrates

Al falfa Aquatic

invertebrates 1 13 21

- day = 1 10 0.0 2 0.12

0. 07

Fish

Alfalfa Fish 113 60

- day = 108 <0.01 54

Hay Fish 42 60

- day = 39 <0.01 20

Fallow/non

- cropped areas Fish 29 60

- day = 28 <0.01 14

Ornamentals Fish 36 60

- day = 34 <0.01 17

Cotton Fish 26 60

- day = 24 <0.01 12

Peanuts Fish 16 60

- day = 16 <0.01 8.0

Asparagus Fish 3.9 60

- day = 3.8 <0.01 1.9

Hops Fish 2.6 60

- day = 2.5 <0.01 1.3

Legumes Fish 6.3 60

- day = 5.8 <0.01 2.9

Corn Fish 6.2 60

- day = 5.8 <<0.01 2.9

A 

### Bold values exceed the chronic risk LOC of 1.0. Alfalfa is the use site with highest EECs.

B 

### RQ = EEC (ppb a.i.)/LC or EC 50 

### (ppb a.i .); EEC is Peak EEC; Fish LC 50 

### = 24,4 00 ppb a.i.; Aquatic Invertebrate

EC 50 

### = 5,3 00 ppb a.i.

C 

### RQ = EEC (ppb a.i.)/NO A EC (ppb a.i.); 21

- d EEC for invertebrates and 60

- d EEC for fish; Fish NO A E C = 2. 0

ppb a.i.; Aquatic Invertebrate NO A EC = 93 0 ppb a.i.



## Table 2 1 . Maximum Clethodim RQ Values for Aquatic Plants A



## Use Site Taxa Peak EEC

(μg a.i./L) Listed

RQ B 

## Non

- listed

RQ B



## Alfalfa Vascular aquatic plants

Non

- vascular aquatic plants 113 0.31

0.0 2 0.08

0.0 1

A 

### Bold values exceed the plant LOC 1.0. Alfalfa is the use site with highest EECs.

B 

### RQ = EEC/EC 50 

### for non

- listed species; EEC/NOAEC for listed species; Duckweed (vascular) EC 50 

### = 1,340 ppb

a.i.; NOAEC = 37 0 ppb a.i.; Marine Diatom (non

- vascular) EC 50 

### = 8,600 ppb a

. i

. ; NOAEC = 5,400 ppb a

. i

.



## 4.2. Non

- target Terrestrial Organisms

4.2.1. Terrestrial Animals

The RQ values for birds and mammals are presented in Table 22 through Table 2 5

. Risk to

birds and mammals are discussed further in the Risk Description section.

## 46 4.2.2. Birds

Clethodim is classified as practically non

- toxic to birds on an acute oral and sub

- acute dietary

exposure basis. Since the endpoints from the acute oral and sub

- acute avian toxicity studies are

non

- definitive ( i.e ., they are ‘greater than’ values), they w ill not be used to calculate RQs. Acute

toxicity data for passerines are not available, and as such there is uncertainty about the effects to

these species. This uncertainty will be discussed in the Risk Description section

.

The RQs calculated for chro nic exposure to birds do not result in RQ values that exceed the

chronic LOC (1 .0 )

. RQ values range from 0.03

- 0.51 , refer to Table 2 2 for a summary of the

chronic avian dietary RQ value s. Risk to birds is discussed further in the Risk Description

section.

Table 2 2

. Avian Chronic Dietary RQ values from Application of Clethodim.

Application Rate (Crop) Dietary Item Chronic RQ 1



## 0.25 lb a.i./A @ 18 apps/7

- d interval

( f

allow land, golf course turf, non

cropped areas; alfalfa ) Short Grass 0.51

Tall Grass 0. 23

Broadleaf plants 0. 29

Fruits/pods/seeds 0. 03

Arthropods 0. 20

Bold values exceed the chronic LOC of 1.0

1 

### Chronic RQ = (EEC, mg/kg

- diet) / chronic NOAEC, mg/kg

- diet; where the chronic NOAEC is 250 mg/kg

- diet



## 4.2.3. Mammals

Clethodim is classified as slightly toxic to mammals on an acute exposure basis. RQ values for

the following use rates exceed the acute listed species LOC (RQ≥0.1) for small (15g) mammals

consuming short grass for all uses with a total annual application rate greater than 2.0 lb a.i./A

( Table 2 3 ) . Also, only the highest use pattern on fallow land, golf course turf, non

- cropped

areas, and alfalfa result s in acute listed species LOC exceedance for medium (35g) mammals

consuming short grass. For all of the remaining use patterns with total annual application rates of

equal to or less than 2.0 lb a.i./A , none of the acute RQs for mammals exceed the Agency’s acut e

listed species LOC (RQ≤0.08). However, there is one exception to this when the total annual

application rate is greater than 2.0 lb a.i./A, if there is a 14

- day interval for the single application

rate of 0.25 lb a.i./A at 18 applications ( Ornamentals, landscaped areas, non

- bearing food crops,

around buildings, bare soil, mulched areas ) there no mammalian acute RQ values exceed the

listed species LOC (RQ ≤0.08 ) ( Table 2 3 ). Acute r isk s to mammals are discussed further in the

Risk Description section.

## 47 T able 2 3 . Mammalian Acute RQ Values for Application of Clethodim

Application Rate

(Crop) Functional Feeding Group

Dietary Item 15 g

mammals 35 g

mammals 1000 g

mammals

Acute 1 

## Acute 1 

## Acute 1



## 0.25 lb a.i./A @18 apps/7

- d

interval (annual app. 4.5 lb

a.i./A) (fallow land, golf course

turf, non

- cropped areas;

alfalfa) Herbivores/Insectivores

Short Grass 0.14 0.12 0.06

Tall Grass 0.06 0.05 0.03

Broadleaf plants 0.08 0.07 0.0 3

Fruits/pods 0.01 0.01 <0.01

Arthropods 0.05 0.05 0.02

Seeds <0.01 <0.01 <0.01

0.25 lb a.i./A @ 9 apps/7

- d

interval (annual app. 2.25 lb

a.i./A) (clover) Herbivores/Insectivores

Short Grass 0.11 0.09 0.05

Tall Grass 0.05 0.04 0.02

Broadleaf plants 0.06 0.05 0.03

Fruits/pods 0.01 0.01 <0.01

Arthropods 0.04 0.04 0.02

Seeds <0.01 <0.01 <0.01

0.19 lb a.i./A @ 18 apps/7

- d

interval (annual app. 3.4 lb

a.i./A) ( grass forage/

fodder/hay) Herbivores/Insectivores

Short Grass 0.10 0.09 0.05

Tall Grass 0.05 0.04 0.02

Broadleaf plants 0.06 0.05 0.03

Fruits/pods 0.01 0.01 <0.01

Arthropods 0.04 0.03 0.02

Seeds <0.01 <0.01 <0.01

0.25 lb a.i./A @ 18 apps/14

- d

interval (annual app. 4.5 lb

a.i./A) ornamentals, landscaped

areas, non

- bearing food crops,

around buildings, bare soil,

mulched areas) Herbivores/Insectivores

Short Grass 0.08 0.07 0.04

Tall Grass 0.04 0.03 0.02

Broadleaf plants 0.04 0.04 0.02

Fruits/pods <0.01 <0.01 <0.01

Arthropods 0.03 0.03 0.01

Seeds <0.01 < 0.01 <0.01

1 

### Acute RQ = (upper bound dose

- based EEC, mg/kg

- bw) / (LD 50 

### ; mg/kg

- bw).



## The dose

- based chronic RQ for mammals exceeded the chronic listed and non

- listed LOC

(RQ≥1.0) for multiple size and dietary classes for all foliar uses with a total annual application

rate greater than 0.5 lbs a.i./A ( Table 2 4 ) . However, there is one exception to this when the

single application rate is 0.125 lb a.i./A, and the total annual application rate is 1.0 or 1.25 lb

a.i./A, there are no mammalian chro nic risk LOC exceedances. RQ values range overall from

1.0

- 3.6 ; refer to Table 2 4 for a summary of the chronic mammalian dose

- based RQ values. On

a chronic dietary

- basis, the RQ values for all uses did not exceed the chronic LOC ( Table 2 5 )

. Table 2 4 an d Table 2 5 summarize the mammalian chronic dose

- and dietary

- based RQs,

respectively, based on foliar applications of clethodim. Chronic r isk s to mammals are discussed

further in the Risk Description section.

## 48 Table 2 4 . Mammalian Chronic Dose

- based RQ values for Application of Clethodim

Application Rate

(Crop) Functional Feeding Group

Dietary Item 15 g

mammals 35 g

mammals 1000 g

mammals

Chronic 1 

## Chronic 1 

## Chronic 1



## 0.25 lb a.i./A @18 apps/7

- d

interval (annual app. 4.5 lb

a.i./A) ( f allow land, golf course

turf, non

- cropped areas; alfalfa) Herbivores/Insectivores

Short Grass 3.6 3.1 1. 7

Tall Grass 1. 7 1.4 0.76

Broadleaf plants 2.0 1.7 0.93

Fruits/pods 0.23 0.19 0.10

Arthropods 1.4 1.2 0.65

Seeds 0.05 0.04 0.02

0.25 lb a.i./A @ 9 apps/7

- d

interval (annual app. 2.25 lb

a.i./A) ( c lover) Herbivores/Insectivores

Short Grass 2.8 2.4 1.3

Tall Grass 1.3 1.1 0.59

Broadleaf plants 1.6 1.4 0.72

Fruits/pods 0.18 0.15 0.08

Arthropods 1.1 0.94 0.50

Seeds 0.04 0.03 0.02

0.19 lb a.i./A @ 18 apps/7

- d

interval (annual app. 3.4 lb

a.i./A) ( g rass forage/ fodder/hay) Herbivores/Insectivores

Short Grass 2.8 2.4 1. 3

Tall Grass 1.3 1.1 0.58

Broadleaf plants 1.6 1.3 0.71

Fruits/pods 0.17 0.15 0.08

Arthropods 1.1 0.92 0.49

Seeds 0.04 0.03 0.02

0.25 lb a.i./A @ 18 apps/14

- d

interval (annual app. 4.5 lb

a.i./A) ( o rnamentals, landscaped

areas, non

- bearing food crops,

around buildings, bare soil,

mulched areas) Herbivores/Insectivores

Short Grass 2.1 1.8 0.96

Tall Grass 0.96 0.82 0.44

Broadleaf plants 1.2 1.0 0.54

Fruits/pods 0.13 0.11 0.06

Arthropods 0.82 0.70 0.38

Seeds 0.03 0.02 0.01

0.25 lb a.i./A @ 4 apps/7

- d

interval (annual app. 1.0 lb a.i./A)

( s od farms

- only in AL, FL, GA,

NC, SC) Herbivores/Insectivores

Short Grass 1. 7 1.4 0.77

Tall Grass 0.77 0.66 0.35

Broadleaf plants 0.94 0.81 0.43

Fruits/pods 0.10 0.09 0.05

Arthropods 0.66 0.56 0.30

Seeds 0.02 0.02 0.01

## 49 Application Rate

(Crop) Functional Feeding Group

Dietary Item 15 g

mammals 35 g

mammals 1000 g

mammals

Chronic 1 

## Chronic 1 

## Chronic 1



## 0.25 lb a.i./A @ 4 apps/ 14

- d

interval (annual app. 1.0 lb a.i./A)

( s pearmint) Herbivores/Insectivores

Short Grass 1.4 1.2 0.65

Tall Grass 0.65 0.55 0.30

Broadleaf plants 0.79 0.68 0.36

Fruits/pods 0.09 0.08 0.04

Arthropods 0.55 0.47 0.25

Seeds 0.02 0.02 0.01

0.125 lb a.i./A @ 16 apps/ 14

- d

interval (annual app. 2.0 lb

a.i./A) ( i.e., t urnip & mustard

greens) Herbivores/Insectivores

Short Grass 1.0 0.89 0.48

Tall Grass 0.48 0.41 0.22

Broadleaf plants 0.59 0.50 0.27

Fruits/pods 0.07 0.06 0.03

Arthropods 0.41 0.35 0.19

Seeds 0.01 0.01 0.01

0.125 lb a.i./A @ 10 apps/ 14

- d

interval (annual app. 1.25 lb

a.i./A) (radishes) Herbivores/Insectivores

Short Grass 0.99 0.84 0.45

Tall Grass 0.45 0.39 0.21

Broadleaf plants 0.56 0.47 0.25

Fruits/pods 0.06 0.05 0.03

Arthropods 0.39 0.33 0.18

Seeds 0.01 0.01 0.01

0.25 lb a.i./A @ 2 apps/7

- d

interval (annual app. 0.5 lb a.i./A)

( i.e., dried beans, Christmas trees,

cotton, forest trees, peanuts,

potatoes, sainfoin, soybeans, sugar

beets, sunflowers, sweet potatoes,

tomatoes, trefoil, yams, lentils) Herbivores/Insectivores

Short Grass 0.95 0.82 0.44

Tall Grass 0.44 0.37 0.20

Broadleaf plants 0.54 0.46 0.25

Fruits/pods 0.06 0.05 0.03

Arthropods 0.37 0.32 0.17

Seeds 0.01 0.01 0.01

Bold values exceed the chronic LOC of 1.0

1 

### Chronic RQ = (upper bound dose

- based EEC, mg/kg

- bw) / (NOAEC; mg/kg

- bw).



## Table 2 5 . Mammalian Chronic Dietary

- based RQ values for Application of Clethodim

Application Rate (Crop) Dietary Item Chronic RQ 1



## 0.25 lb a.i./A @18 apps/7

- d interval

(annual app. 4.5 lb a.i./A) ( f allow land, golf

course turf, non

- cropped areas; alfalfa) Short Grass 0.85

Tall Grass 0.39

Broadleaf plants 0.48

Fruits/pods/seeds 0.05

Arthropods 0.33

1 

### Chronic RQ = (EEC, mg/kg

- diet) / chronic NOAEC, mg/kg

- diet; where the chronic NOAEC is 500 mg/kg

- diet

## 50 4.3. Terrestrial Invertebrates

Clethodim is classified as practically non

- toxic to non

- target terrestrial invertebrates on an acute

contact exposure basis (LD 50 

## >100 μg a.i./bee). RQ values could not be calculated because no

definitive toxicity endpoints were available for honeybees. Risk to terrestrial invertebrates is

discussed further in the Risk Description section.

4.4. Non

- target Terrestrial and Semi

- aquatic Plants

Clethodim is a post

- emergence selective herbicide used on a variety of crops and non

- crop areas

to control a variety of grasses (monocotyle don plant species in the Poaceae family ). Definitive

toxicity values are available only for monocot plant species for clethodim; therefore, RQ values

were not determined for dicot plants. All uses result i n LOC exceedances to both listed and non

listed terrestrial monocot plants from runoff i n semi

- aquatic environments , and listed monocot

plants from drift and runoff to dry environments

. Uses with application rates greater than 0.10 lb

a.i./A also resulted in risk to non

- listed monocot plants from drift, and uses greater than 0.125 lb

a.i./A resulted in risk to listed and non

- listed monocot plants from runoff and drift to all

environments. For foliar aerial and chemigation uses of clethodim RQ values range from 0.41 to

156.25 and for foliar ground uses of clethodim RQ values ranged from 0.42 to 131.25 ( Table

2 6 ). Again, three of the four monocot plant species that showed effects (corn, ry egrass, and oat)

all belong to family Poaceae, the grass family (whic h is the same family as the target species of

clethodim), whereas onion (which showed no effects) is in a different monocot family, family

Liliaceae. Additional refinements and a spray drift analysis were completed and risk to terrestrial

plants is discuss ed further in the Risk Description section.

Table 2 6 . Terrestrial Monocot Plants Inhabiting Dry and Semi

- aquatic Areas Exposed to

Clethodim via Runoff and Drift

Application Rate

(Crop) Spray drift Dry area Semi

- aquatic area

Listed

Species

RQ 1 

## Non

- listed

Species

RQ 2 

## Listed

Species

RQ 1 

## Non

- listed

Species

RQ 2 

## Listed

Species

RQ 1 

## Non

- listed

Species

RQ 2



## Foliar Aerial and Chemigation Applications

0.25 lb a.i./A (Aerial

- f allow land,

golf course turf, non

- cropped areas,

alfalfa, clover, dried beans,

Christmas trees, cotton, forest trees,

peanuts, potatoes, sainfoin,

soybeans, sugar beets, sunflowers,

sweet potatoes, tomatoes, trefoil,

yams, mint, lentils, sod farms);

(Chemigation

- garlic and onions ) 5.25 4.17 43.75 2.30 156.25 8.22

## 51 Application Rate

(Crop) Spray drift Dry area Semi

- aquatic area

Listed

Species

RQ 1 

## Non

- listed

Species

RQ 2 

## Listed

Species

RQ 1 

## Non

- listed

Species

RQ 2 

## Listed

Species

RQ 1 

## Non

- listed

Species

RQ 2



## 0.125 lb a.i./A (Aerial

- t urnip greens,

mustard greens, herbs, beets, b rassica

vegetables, carrots, cranberries,

cucurbit vegetables, fruiting

vegetables, leafy vegetables,

strawberries, radishes , tree fruits, tree

nuts, asparagus, hops, safflower,

sesame , artichokes, bushberries

including cranberries, caneberries,

peaches, flax, meadowfarm, seeds,

succulent beans, legume vegetables,

dried and succulent peas ) 2.72 2.08 21.88 1.15 78.13 4.11

0.10 lb a.i./A (Aerial

- c anola) 2.17 1.67 17.50 0.92 62.50 3.29

0.045 lb a.i./A (Aerial

- c orn

- field) 0.98 0.75 7.88 0.41 28.13 1.48

Foliar Ground Applications

0.25 lb a.i./A ( o rnamentals,

landscaped areas, non

- bearing food

crops, around buildings, bare soil,

mulched areas) 1.09 0.83 18.75 0.99 131.25 6.91

0.125 lb a.i./A (sage, kenaf) 0.54 0.42 9.38 0.49 65.63 3.45

Bold values exceed the terrestrial plant LOC of 1.0

1 

### Listed Plant species RQ = (EEC) / EC 25

2 

### Non

- listed Plant species RQ = (EEC) / NOAEC (EC 05 

### )



## 5. RISK DESCRIPTION

5.1. Risks to Aqu atic Organisms

5.1.1. Fish (surrogate s for aquatic

- phase amphibians)

Exposures to clethodim residues of concern resulted in RQ values that exceeded the chronic risk

LOC (1.0) for fish (surrogates for aquatic

- phase amphibians) for all 67 labeled uses and use

groups of clethodim ( Table 20 )

. There w as no acute risk ( listed or non

- listed ) LOC exceedances

for fish ( Table 20 )

.

Using the highest exposure estimates for alfalfa, the chronic LOC (RQ>1.0) is continuously

exceeded (RQ>2) from the first year until the end of the model simulation ( Figure 1 ).

## 52 Figure 1. Exposu re estimates from the maximum use pattern on alfalfa

Although t he chronic level of concern was exceeded for all uses of clethodim

, there are

numerous uncertainties associated with this risk call. First, the only available chronic fish

toxicity study using fathead minnow did not measure the typical sublethal (growth or

reproduction) endpoints for fish, the only endpoint that was measured was survival; and

therefore, the NOAEC could potentially be an underestimation of risk to fish , and actual

endpoint could potentially be even lower . Second, the most sensitive acute fish toxicity value

was for a different species (rainbow trout), and the chronic toxicity value that was used in the

risk assessment is an ACR derived NOAEC that relies on an extrapolation among species

(fathead minnow) ; to try and account for the potential difference in sensitivity among species on

an acute and chronic basis.

Third, there is a lack of aerobic aquatic metabolism data resulting in a conservative assumption

for aquatic exposure modeling. Fourth, there is a lack of toxicity data for the residues of concern

resulting in the assumption that they are no more or less toxic than the parent compound b ecause

its toxic moiety appears to potentially be intact (USEPA, 2008). I f the degradates of concern

were shown to be much less toxic than clethodim, then exposure estimates and the resulting RQ

values for clethodim alone in this assessment woul d be 4

- 13x lower

. When clethodim is

modeled alone, the risk to listed and non

- listed fish on a chronic exposure basis for use on alfalfa

is decreased by 13x (8.6 μg/L versus 108 μg/L). However, t his change in aquatic exposure

modeling do es not decrease t he RQ value below the chronic risk LOC for fish (surrogates for

aquatic

- phase amphibians) , which is also the case for any use of clethodim with multiple

applications allowed per year

. If both 1) the degradates of concern were shown to be much less

toxic t han clethodim and 2) uses were limited to one application per year , then RQ values for

clethodim alone in this assessment would decrease to a value below the chronic risk LOC for

fish.

In summary, concern levels were exceeded for chronic exposures to fish and aquatic phase

amphibians. In addition, fish may be indirectly impacted by potential impacts to monocot plants

(risks to monocot plants are discussed below). 0 20 40 60 80 100 120 140

1/1/1965 6/24/1970 12/15/1975 6/6/1981 11/27/1986Concentration (μg/L)



### Date

## 53 5.1.2. Aquatic Invertebrate s

Exposures to clethodim residues of concern did not result in RQ values that exceeded the acute

listed species or chronic listed or non

- listed species LOCs (0.05 and 1.0, respectively) for aquatic

invertebrates

. However, based on the adverse direct effe cts to fish (surrogates for aquatic

- phase

amphibians) (on a chronic exposure basis) , and terrestrial monocot plants, as discussed below,

there is still the potential for indirect effects to aquatic invertebrates resulting from changes in

the aquatic ecosystem

.

5.1.3. Aquatic Plants

There were no LOC excee dances for aquatic plants expos ed to clethodim residues of concern

. Aquatic vascular plants were the most sensitive aquatic plant species to clethodim (EC 25 

## = 1.34

mg a.i./L; NOAEC = 0.94 mg a.i./L), an d they did not result in risk to listed or non

- listed aquatic

plants. Although t here is open literature data for aquatic non

- vascular plants that show a more

sensitive EC 25 

## value than registrant submitted data, the toxicity value is still less toxic than the

aquatic vascular plant toxicity data, which did not show risk s of concern from exposure to

clethodim

. However, based on the adverse effects to fish (surrogates for aquatic

- phase

amphibians) (on a chronic exposure basis) , and terrestrial monocot plants , as discussed below,

there is still the potential for indirect effects to aquatic plants resulting from changes in the

aquatic ecosystem.

5.2. Risks to Terrestrial Organisms

5.2.1. Terrestrial Animals

5.2.1.1. Birds (surrogates for reptiles an d terrestrial

- phase amphibians)

There were no avian mortalities observed in the acute oral or sub

- acute dietary toxicity studies at

the highest treatment levels that were tested ( i.e ., LC 50 

## endpoints are ‘greater than’ values);

therefore, these endpoints were not used to calculate RQ va lues. However, in the acute oral

bobwhite quail study overt signs of toxicity ( i.e., lethargy, wing droop and ruffled appearance)

and a reduction of body weight gain was observed in the 1650 mg a.i./kg

- bw concentration, and

no effects (lethal or sublethal ) were observed in the 1250 mg a.i./kg

- bw concentration. A

comparison of the dose

- based EEC values to the no mortality level and the concentrations at

which sublethal effects were observed is presented in Figure 2 . There were no effects observed

in the s ub

- acute dietary toxicity study, and a comparison of the dietary

- based EEC values to the

no effect level (representing mortality and sublethal effects) is presented in Figure 3

.

## 54 Figure 2. Comparison of the acute dose

- based EEC values for small (20g) birds consuming

short grass to levels where sublethal effects were observed.

Figure 3

. Comparison of the dietary

- based EEC values for small (20g) birds consuming

short grass to no effect levels from the sub

- acute dietary toxicity study

.

For small birds (20g) consuming short grass the maximum dose

- based EEC value that was

calculated (484 mg a.i./kg

- bw) was for the maximum annual application rate (4.5 lb a.i./A) that

was modeled. The maximum application rates that were modeled were all based on conservat ive 0 200 400 600 800 1000 1200 1400 1600 1800 2000

18 9 6 3 2Avian Acute Dose-based EEC Values for ShortGrass (mg a.i./kg-bw)



### # of applications per year

Fallow land Clover Ornamentals Alfalfa Hay 

## Sublethal effects were observed = 1650 mg a.i./kg

- bw Highest test concentration; no mortality, sublethal effects were observed; LD50 > 2000 mg a.i./kg

- bw



## No sublethal effects observed = 1250 mg a.i./kg

- bw

No sublethal effects observed = 875 mg a.i./kg

- bw

No sublethal effects observed = 500 mg a.i./kg

- bw

0 300 600 900 1200 1500 1800 2100 2400 2700 3000 3300 3600 3900

18 9 6 3 2Avian Sub-acute Dietary-based EEC Values forShort Grass (ppm)



### # of applications per year

Fallow land Clover Ornamentals Alfalfa Hay 

## No effects were observed at 2750 mg/kg

- diet Highest concentration; no mortality & no sublethal effects were observed LC50 > 3978 mg a.i./kg

- diet



## No effects were observed at 1290 mg/kg

- diet

No effects were observed at 600 mg/kg

- diet

## 55 assumptions. The maximum dose

- based EEC value (484 mg a.i./kg

- bw) is three (3) times less

than the lowest test level at which sublethal effects were observed. The maximum dietary

- based

EEC value (425 mg a.i./kg

- diet) is nine (9) times less than the h ighest test concentration (3978

mg a.i./kg

- diet) , where no effects (lethal or sublethal) were observed.

The re were no chronic listed and non

- listed LOC exceedances for birds ( Table 20 ). However,

there is only one avian reproduction study available for clethodim and no effects on survival,

behavior, growth or reproduction were observed in mallard ducks. T herefore, there is some

uncertainty if the northern bobwhite quail would have similar sensitivity to chronic clethodim

exposure. Therefore, to further characterize the potential risk to birds on a chronic basis, avian

reproduction data for chemicals of the same cyclohexene oxime herbicide family class were

reviewed; tralkoxydim (PC 121000 ), sethoxydim (PC 121001), and tepraloxydim (PC 121005).

Sethoxydim (PC 121001) and tepraloxydim (PC 12100 5) both have at least one avian

reproduction toxicity study with observed definitive endpoints ; there were issues with the control

birds in the tralko xydim avian reproduction studies, and therefore the data could not be used for

comparison

.

Sethoxydim is the only chemical with both mallard and bobwhite quail avian reproductive

toxicity data, and based on the results of these studies, the mallard duck was the more sensitive

bird species (NOAEC = 512 ppm and LOAEC = 1047 ppm (expressed as clethodim a.i.), based

on reduction in hatchability; MRID 48000901). No effects were observed in the sethoxydim

bobwhite quail reproductive toxicity test (MRID 440034 01). For tepraloxydim, the bobwhite

quail is the only reproductive toxicity data available (NOAEC = 382 ppm and LOAEC = 1093

ppm (expressed as clethodim a.i.), based on reduction in hatchability, reduction in percent

normal hatchlings of eggs laid, reduct ion in normal hatchlings of eggs set, and reduction of 14

- day old survivors of eggs set; MRID 44467123). For both of these other chemicals the

concentration where the lowest effects where observed were both greater than the maximum test

concentration of clethodim, in which no effects were observed. A comparison of the dietary

based EEC values to the no effect level is presented in Figure 4

.

## 56 Figure 4. Comparison of the dietary

- based EEC values for small (20g) birds consuming

short grass to NOAEC leve ls in the chronic dietary toxicity stud ies available for

cyclohexene oxime herbicide family class of chemicals

.

The maximum dietary

- based EEC value (425 mg a.i./kg

- diet) is two (2) times less than the

highest test concentration (833 mg a.i./kg

- diet), where no effects (lethal or sublethal) were

observed. Based on the results of the chronic toxicity clethodim does ap pear to be less toxic on a

chronic exposure basis than the other two cyclohexene oxime herbicide family chemicals

(sethoxydim and tepraloxydim ).

F or both acute and chronic exposure measurements, it is important to note a major uncertainty ;

t he EECs used in the RQ calculations for birds were based on the single maximum application

rate using the minimum application interval between successive applications. It is important to

note that the estimated EEC values are based on conservative assumptions that we re made

regarding the application methodology of clethodim. In the absence of label directions for the

maximum annual application, the potential total number of crop cycles were used to conduct a

screening

- level risk assessment. T he modeled input pa ramet ers, used very conservative

assumptions that new crop cycles would be occurring every two weeks; however, that may not

be realistic representation of field practices . Therefore, if additional information was provided

for annual application limits and crop cycle duration , a more refined analysis could be

completed, and under more realistic conditions the EEC values would likely decrease

. However,

there are no LOC exceedances for listed and non

- listed birds on a chronic basis

.

In combination with the lack of reproductive effects to mammals when exposed to clethodim (as

d iscussed below), available chronic toxicity data for two cyclohexene oxime herbicide family

chemicals, and the potential decrease d dose

- based and dietary

- based EEC values based on field

practices

, potential direct effects to listed and non

- listed birds on an acute and /or chronic

exposure basis is below concern levels

. However, based on the adverse effects to terrestrial

monocot plants, as discussed below, there is still the potential for indirect effects to birds 0 125 250 375 500 625 750 875 1000

18 9 6 3 2AvianChronic Dietary-based EEC Values forShort Grass (ppm)



### # of applications per year

Fallow land Clover Alfalfa Hay 

## Highest test concentration; no effects: NOAEC = 833 ppm clethodim a.i.

Sethoxydim ; reduced hatchability; Mallard: NOAEC = 512 ppm (as clethodim a.i.)

Tepralkoxydim; reduced hatchability; Bobwhite: NOAEC = 382 ppm (as clethodim a.i.)

Sethoxydim; Mallard: L OAEC = 1047 ppm (as clethodim a.i.) Tepralkoxydim ; Bobwhite: L OAEC = 1093 ppm (as clethodim a.i.)

## 57 (surrogates for terrestrial

- phase amphibians) resulting from changes in the diet and habitat of

listed birds (surrogates for terrestrial

- phase amphibians)

.

5.2.1.2. Mammals

For the all uses of clethodim, there were no LOC exceedances for non

- listed mammals on an

acute exposure basis (dose

- based). On an acute exposure basis there were LOC exceedances for

listed small (15g) mammals consuming short grass for all uses with a total annual application

rate greater than 2.0 lb a.i./A ( Table 21

, RQs = 0.10

- 0.14), and medium (35g) mammals

consuming short grass at the highest use pattern on fallow land, golf course turf, non

- c ropped

areas, and alfalfa ( Table 21

, RQ = 0.12)

. A comparison of the dose

- based EEC values for small

and medium sized mammals to the no mortality level and the concentrations at which sublethal

effects were observed is presented in Figure 5 and Fig ure 6 , respectively. For all of the

remaining use patterns of clethodim with total annual application rates of equal to or less than

2.0 lb a.i./A ( Table 3 ), or if there is a 14

- day interval for the maximum single application rate of

0.25 lb a.i./A ( i.e., orna mentals, landscaped areas, non

- bearing food crops, around buildings, bare

soil, mulched areas), there were no acute listed species LOC exceedances ( Table 21

, RQ≤0.08).

Figu re 5

. Comparison of the dose

- based EEC values for small (15g) mammals consuming

short grass to concentrations where mortality and sublethal effect were observed in the

acute oral toxicity study. 0 250 500 750 1000 1250 1500 1750 2000 2250 2500

18 9 6Acute Mammalian dose-based EECs (small 15g)mammals consuming short grass (mg a.i./kg-bw)



### # of applications per year

Fallow land Clover Ornamentals Alfalfa Hay Highest test concentration; mortality and sublethal effects were observed = 2500 mg/kg

- bw (M)

Highest test concentration; mortality and sublethal effects were observed = 2000 mg/kg

- bw (F)



## LD50 = 1360 mg/kg

- bw (F)

Sub lethal effects were observed = 800 mg/kg

- bw Sub lethal effects were observed = 1450 mg/kg

- bw Sub lethal effects were observed = 1860 mg/kg

- bw

LD50 = 1630 mg/kg

- bw (M)

## 58 Figure 6

. Comparison of the dose

- based EEC values for medium ( 3 5g) mammals

consuming short grass to concentrations where mortality and sublethal effect were

observed in the acute oral toxicity study.

For mammals, although the chronic LOC was exceeded for multiple size classes and dietary

items, no reproductive effects were observed in the mammalian two

- generation reproduction

study

. All uses with an annual application rate of less than 1.25 lb a.i./A , based on conservative

assumptions do not result in chronic risk to mammals ( Table 22 ). Chronic dose

- based RQ

values for uses with application rates greater than 1.25 lb a.i./A ranged from 1.04

- 3.62 ( Table

22 ). D ietary

- based RQs did not exceed the chronic LOC for any use of clethodim ( Table 23 ).

The NOAEC (500 ppm; 51 mg/kg

- bw/day) from the two

- generation mammalian reproduction

toxicity study was based on decreased body weight and food consumption in parental organisms

at the 2500 ppm test concentration ( approx. 263 mg/kg

- bw/day). There were no adverse effects

on reproductive performance or survival of either generation during the two

- generat ion toxicity

study. Comparisons of the dose

- based EEC values to the levels where effects to adults were and

were not observed are presented in Figure 7 . The maximum dose

- based EEC value ( 405 ) is 8

times greater than the highest test concentration ( 51 mg/ kg

- bw/day ), where no effects were

observed. 0 250 500 750 1000 1250 1500 1750 2000 2250 2500

18 9 6Acute Mammalian dose-based EECs (medium 35g)mammals consuming short grass (mg a.i./kg-bw)



### # of applications per year

Fallow land Clover Ornamentals Alfalfa Hay 

## LD50 = 1630 mg/kg

- bw (M)

LD50 = 1360 mg/kg

- bw (F) Highest test concentration; mortality and sublethal effects were observed = 2500 mg/kg

- bw (M)

Highest test concentration; mortality and sublethal effects were observed = 2000 mg/kg

- bw (F)



## Sub ethal effects were observed = 1860 mg/kg

- bw

LD50 = 1630 mg/kg

- bw (M)

Sub lethal effects were observed = 1450 mg/kg

- bw

LD50 = 1360 mg/kg

- bw (F)

Sub lethal effects were observed = 800 mg/kg

- bw

## 59 Figure 7. Comparison of the dose

- based EEC values for small (20g) mammal s consuming

short grass to NOAEL/LOAEL levels in the chronic toxicity study for mammals.

However, it should be noted that a majority o f these acute and chronic LOC exceedances for

multiple dietary items, and size classes of mammals are for use patterns that do not have detailed

annual application rates, and often have multiple crop cycles per year ( i.e., fallow land, golf

course turf, non

- cropped areas; alfalfa; clover; and grass forage/fodder/hay). T he EECs used in

the RQ calculations for mammal s were based on the single maximum application rate using the

minimum application interval between successive a pplications. It is important to note that the

estimated EEC values are based on conservative assumptions that were made regarding the

application methodology of clethodim. In the absence of label directions for the maximum

annual application, the potenti al total number of crop cycles were used to conduct a screening

level risk assessment. Also, the modeled input parameters, used very conservative assumptions

that new crop cycles would be occurring every two weeks; however, that may not be realistic

repre sentation of field practices. Therefore, if additional information was provided for annual

application limits and crop cycle duration , a more refined analysis could be completed, and under

more realistic conditions the EEC values would likely decrease, wh ich in turn could reduce RQ

values to below the LOCs

.

In combination with the lack of reproductive effects to mammals when exposed to clethodim

, and the likelihood of decreased dose

- based and dietary

- based EEC values with additional

information , direct effects to listed and non

- listed mammal s on an acute and chronic exposure

basis is unlikely

. However, based on the adverse effects to terrestrial monocot plants, as

discussed below, there is still the potential for indirect effects to mammals resulting fr om

changes in the diet and habitat of listed mammal s. 0 50 100 150 200 250 300 350 400 450 500

18 9 6 3 2 1Mammalian chronic dose-based EECs small (15g)mammals (mg a.i./kg-bw)



### # applications per year

Fallow land Clover Ornamentals Alfalfa Hay 

## LOAEL = 263 mg/kg

- bw/day (2500 ppm); reduced body weight & food consumption

NOAEL = 51 mg/kg

- bw/day (500 ppm); No effects

## 60 5.2.1.3. Terrestrial Invertebrates

Based on the acute contact honeybee study, clethodim is classified as practically non

- toxic. In

the acute contact study with the Select 2EC formulation, a lthough 22% mortality was observed

in the 100 μg a.i./bee dose group , the 48

- hour LD 50 

## was >100 μg a.i./bee . No signs of toxicity

were observed in dose groups less than 100 μg a.i./bee , the resulting no

- effect dose level was 60

μg a.i./bee. Although there is no toxicity data for other life stages of honey bee, which could

result in differences not captured by adult acute toxicity studies, there appears to be a low

likelihood of potential direct effects to terrestrial invertebrates from clethodim use.

5.2.2. Terrestrial Plants

Clethodim is a post

- emergence selective herbicide used on a variety of crops and non

- crop areas

to control a variety of grasses (monoc otyledon plant species in the poaceae family ). TerrP lant

(version 1.2.2, 05/28/2013) was used to calcu late EECs from runoff and drift resulting from a

single pesticide application, and are presented in Table 24. There were no adverse effects

observed for dicot plants, and therefore RQ values were not determined for dicot plant species.

All uses of cleth odim result in LOC exceedances to both listed and non

- listed terrestrial monocot

plants from runoff i n semi

- aquatic environments , and listed monocot plants from drift and runoff

to dry environments

. Uses of clethodim with a single application greater than 0.125 lb a.i./A

resulted in risk to listed and non

- listed monocot plants from runoff and drift to all environments.

Of the four monocot plant species that were tested, three, (corn, ryegrass, and oat) showed

adverse effects to clethodim application, whereas onion did not show any adverse effects to

clethodim application. The three species (corn, perennial ryegrass, and oats) all belong to family

Poaceae, the grass family (which is the same family as the target species of clethodim), whereas

onion (which showed no effects) is in a different monocot family, family Liliaceae. However,

there are numerous other monocot families that are not represented, but there is evidence to

suggest based on the mod e of action of clethodim, and the mechanism of selectivity within grass

species for the ACCase enzyme site of action, suggests that there are differential sensitivity

between grass species, and species (Hess, 1997).

Although there were two reported inci dents in the EIIS database involving clethodim and

terrestrial dicot plants (I002969

- 058 and I022217

- 034), both of these incident s w ere of

undetermined legality and clethodim was listed as a “ possible ” cause of the alleged damage to

cotton and soybean. Co tton and soybeans are dicots, and based on the available toxicity data for

clethodim, these species would not be expected to be sensitive to clethodim as it is an herbicide

that targets monocot grass species. Although very little information is available for I002969

- 058, the cotton crop injury that was observed after the use of Select 2EC (the active ingredient is

clethodim) , tissue testing was completed to determine that Select (clethodim a.i.) was not likely

the cause of the injury. However, it is uncle ar if another pesticide was involved in this incident.

For I022217

- 034, the damage to the soybean crop after the product Ignite 280 SL (a.i.

glufosinate

- ammonium) and Select (a.i. clethodim) were applied was likely the result of tank

contamination; howeve r, it is not clear which chemical the tank contaminated wit (clethodim or

glufosinate

- ammonium ). However, it should be noted that glufosinate

- ammonium does have

## 61 definitive toxicity data available and effects observed on dicot and monocot plants (USEPA,

20 13)

.

To evaluate exposure from spray drift, AgDrift (v2.1 .1 ) was used. Due to plant LOC

exceedances for all application rates, AgDrift was used to estimate the distances from the edge of

the field for which risks to non

- listed and listed monocot plant species extend to for aerial and

ground spray applications

. For aerial applications AgDrift was r u n using large (medium to

coarse and coarse to very coarse) droplet size distribution, and application rates of 0.045 to 0.25

lbs a.i./A ; and for ground applications AgDrift was run using high and low boom ground spray

, fine to medium/coarse droplet size distributions, and application rates of 0.25 and 0.125 lbs

a.i./A ( Table 2 7 and Table 28 , non

- listed and listed monocots, respectively). Example

input/outputs from AgDrift for clethodim can be found in Appendix F

.

Table 2 7 . Distances from the edge of the field for which risks extend for non

- listed monocot

plant specie s exposed to clethodim

.

Applicat i o n

method Droplet size distribution App lication

rate

(lb a.i./A ) Distance (ft ) for

vegetative v igor

endpoint 1 

## Distance (ft) for

seedling emergence

endpoint 2



## Aerial medium

- coarse 0.25 358 171

coarse

- very coarse 233 118

medium

- coarse 0.125 203 95

coarse

- very coarse 137 69

medium

- coarse 0.10 174 79

coarse

- very coarse 118 49

medium

- coarse 0.045 85 26

coarse

- very coarse 62 23

Ground fine to medium/coarse; high boom height 0.25 52 16

fine to medium/coarse; low boom height 26 10

fine to medium/coarse; high boom height 0.125 23 10

fine to medium/coarse; low boom height 13 7

1 

### Most sensitive vegetative vigor EC 25 

### = 0.003 lb a.i./A ( ryegrass ), most sensitive parameter was dry weight.

2 

### Most sensitive seedling emergence EC 25 

### = 0.0076 lb a.i./A ( o at), most sensitive parameter was plant height.



## Table 28 . Distances from the edge of the field for which risks extend for listed monocot

plant specie s exposed to clethodim

.

Application

method Droplet size distribution Application

rate

(lb a.i./A) Distance (ft) for

vegetative vigor

endpoint 1 

## Distance (ft) for

seedling emergence

endpoint 2



## Aerial medium

- coarse 0.25 463 >997

coarse

- very coarse 289 >997

medium

- coarse 0.125 253 >997

coarse

- very coarse 171 955

medium

- coarse 0.10 213 >997

coarse

- very coarse 144 682

medium

- coarse 0.045 112 479

coarse

- very coarse 75 299

Ground fine to medium/coarse; high boom height 0.25 72 525

fine to medium/coarse ; low boom height 39 367

## 62 fine to medium/coarse ; high boom height 0.125 30 259

fine to medium/coarse; low boom height 16 157

* EC 05 

### is used when a NOAEC could not be calculated or NOAEC is higher than the EC 25

1 

### Most sensitive vegetative vigor NOAEC* = 0.0023 lb a.i./A ( ryegrass ), most sensitive parameter was dry weight.

2 

### Most sensitive seedling emergence NOAEC* = 0.0004 lb a.i./A ( o at), most sensitive parameter was plant height.



## B ased on the AgDrift spray drift analysis, and the refinements made for aerial applications

, all

aerial uses of clethodim result in risk to list ed terrestrial monocot plants, at distances of 75 to

>997 feet from the edge of the field ; and r isk s to non

- listed terrestrial monocot plants extend 7 to

358 feet from the edge of the field. For ground applications, based on the refinement of boom

height risks to listed terrestrial monocot plants, at distances of 16 to 367 feet from the edge of

the field ; and r isk s to non

- listed terrestrial monocot plants extend 7 to 26 feet from the edge of

the field

.

The direct risk to listed and non

- listed terrestrial dicot plant s from clethodim use is anticipated to

be very low. However, based on the information above, and the anticipated off

- field effect area,

risk to listed and non

- listed monocot plant s , specifically those in the Poaceae (grass) family,

from clethod im use is anticipated to be very high

.

5.3. Probit Slope Response Analysis of LOC Values and Acute RQ Values

As part of the risk estimation, the odds of an individual effect (mortality) from exposure to

clethodim were estimated. The probability of mortality calculations are based on the probit slope

dose

- response relationship from acute studies. The probability of mortality for an exposed

individual are calculated using an Excel spreadsheet tool IECV1.1 (Individual Effect Chance

Model Version 1.1) developed by EFED of the U.S. EPA, OPP, Environmental Fate and Effects

Division (June 22, 2004).

The acute toxicity results consisted of limit dose type tests ( e.g ., avian acute oral toxicity ) , and

other acute studies which d id not provide data which can be used to calculate a probit dose

response slope. In these cases (for acute fish and avian acute oral), the odds of mortality were

only calculated for the listed acute LOC using the default slope of 4.5 (95% CL 2, 9). A probit

slope was available for the following studies: acute mammal, and aquatic invertebrate toxicity.

T he probit slope for the acute oral toxicity s tudy with the rat was 1.39; 95% CL of 0.84 and 2.30

, the probit slope for the acute toxicity study with the daphnid was 4.57; 95% CL of 2.62 , and

6.53, and the probit slope for the shell deposition toxicity study with the oyster was 2.04; 95%

CL of 1.78, a nd 2.30

. The odds of mortality for an individual at the RQ value or endangered

species LOC for terrestrial and aquatic animals based on the slopes discussed in the previous

paragraph are provided in Table 2 9

.

## 63 Table 2 9 . Probit Slope and Odds of Mortality for an Individual at the RQ/LOC for Uses of

Clethodim

Listed

Species Birds 1 

## Mammals Fish 2 

## Aquatic Invertebrates

Freshwater

(Daphnids) Estuarine /

Marine

(Oyster)

RQ/LOC 0.1 (LOC) RQ (15 g & 35 g mammals) =

0.14 & 0.12 (fallow land, golf

course turf, non

- cropped areas;

alfalfa);

RQ (15 g mammals) = 0.1 1

(clover);

RQ (15 g mammals) = 0.10 ( grass

forage/ fodder/hay) 0.05 (LOC) RQ = 0.006 RQ = 0.02

Slope 4.5 1 

## 1.39 4.5 2 

## 4.57 2.04

Slope

95% CL 2, 9 1 

## 0.84, 2.30 2, 9 2 

## 2.62, 6.53 1.78, 2.30

Odds of

individual

effect 1 in 2.94 x 10 5 

## 1 in 8.5 & 1 in 10 (15 g & 35 g

mammals) (fallow land, golf

course turf, non

- cropped areas;

alfalfa);

1 in 11 (15 g mammals) (clover);

1 in 12.2 (15 g mammals) ( grass

forage/ fodder/hay) 1 in 4.18 x 10 8 

## 1 in 4580 1 in 48.4

95% CL 1 in 44,

1 in 8.86 x 10 18 

## 1 in 4.23,1 in 40.4 & 1 in 4.55, 1

in 58.5 (15 g & 35 g mammals)

(fallow land, golf course turf,

non

- cropped areas; alfalfa);

1 in 4.8, 1 in 72.8 (15 g

mammals) (clover);

1 in 5, 1 in 93.2 (15 g mammals)

( grass forage/fodder/hay) 1 in 216,

1 in 1.75 x 10 31 

## 1 in 45.7,

1 in 3.98 x 10 6 

## 1 in 26.6,

1 in 93.2

1 

### As the study resulted in a non

- definitive value (LC 50 

### > highest concentration tested) , and the use of a probit model

was not appropriate ; therefore, default mean slope value (4.5) and 95% CL (2, 9) is used.

2 

### For the freshwater fish toxicity study no mortalities were observed in the study, and the use of a probit model was

not appropriate ; therefore, default mean slope value (4.5) and 95% CL (2, 9) is used. The estuarine/marine fish

toxicity study resulted in a non

- definitive value (LC 50 

### > highest concentration tested) , and the use of a probit model

was not appropriate ; therefore, default mean slope value (4.5) and 95% CL (2, 9) is used.



## Based on the calculated odds of mortality for an individual effect using conservative assumptions

for the highest application rate, the odds for an individual effect for terrestrial organisms are as

follow s: birds range from <0.01 to 2%; and for mammals range from 2 to 23% (for small, 15g

, mammals) and 2 to 22% (for medium, 35g

, mammals)

. Although there are no LOC exceedances

for aquatic organisms (RQ<0.05) , the odds for an individual effect range from <0. 01 to 0.5% for

fish; <0.01 to 2% for freshwater invertebrates; and 1 to 4% for estuarine/marine invertebrates.

## 64 5.4. Re

- evaluation of the Risk Hypothesis

The results of this preliminary risk assessment indicate that the uses of clethodim have the

potential for direct adverse effects to listed and non

- listed non

- target monocot plants, chronic

risk to birds (and, thus, reptiles and terrestrial

- phase amphibians), and mammals, acute effects to

mammals, and potential acute effects to birds ( and, thus, reptiles a nd terrestrial

- phase

amphibians)

, and chronic effects to freshwater and estuarine/marine fish. Therefore, the risk

hypotheses based on the risk assessment [ Clethodim, when used in accordance with the label,

results in potential adverse effects upon survival, growth, and reproduction of non

- target

monocot plants, especially within family Poaceae, exposed to runoff and drift from areas >1000

feet from the edge of fields treated with clethodim. Use of clethodim also results in potential

adverse effects to fish when exposed on a chronic basis to drift and runoff from areas treated

with clethodim. Although clethodim is fairly non

- persistent, it is mobile and is exp ected to occur

in adjacent aquatic ecosystems on a continuous or recurrent basis. Also, the major toxic

degradates of concern (clethodim sulfoxide and clethodim sulfone) are much more mobile and

persistent than the parent. Thus, there is a possibility for exposure to the residues of concern

(parent plus degradates) to non

- target organisms from use of clethodim ]

, was not disprove n

.

6. REFERENCES

Herbicide Resistance Action Committee ( HRAC ) . 2012. The World of Herbicides Map (dated

2010). http://www.hracglobal.com/Publications/WorldofHerbicidesMap.aspx

Hess, D. F., 1997. Mode of Action of Lipid Biosynthesis Inhibitors (Graminicides

- ACCase

Inhibitors) In Herbicide Action: An Intensive Course on (activity, selectivity, behavior,

fate) herbicides in plants and the environment . Perdue University , pp

. 290

- 309.

Hoerge r, F. and E. E. Kenaga. 1972. Pesticide Residues on Plants: Correlation of Representative

Data as a Basis for Esti mation of thei r Magnitude in the Environment. In F. Coulston and

F. Korte, eds., Environmental Quality and Safety: Chemistry, Toxicology, and

Technology, Georg Thieme Publ., Stuttgart, West Germany, pp. 9

- 28.

U.S. Environmental Protection Agency ( USEPA )

. 1993. Wildlife Exposure Handbook

, United

States Environmental Progection Agency . Washington, D. C.: Government Printing

Office. http://www.epa.gov/ncea/pdfs/toc2

- 37.pdf (Accessed June 19, 2009).

USEPA. 1998. G uidelines f or Ecological Risk Assessment. Risk Assessment Forum, Office of

Research and Development, Washington , D.C. EPA/630/R

- 95/002F. April 1998.

http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=30759

USEPA. 2004. Overview of the Ecological Risk Assessment Process in the Office of P esticide

Programs. U.S. Environmental Protection Agency, Office of Prevention, Pesticides and

Toxic Substances, Of fice of Pest icide Programs, Washington DC. January 23, 2004.

## 65 USEPA. 2006. User’s Guide TerrPlant version 1.2.2

. United States Environmental Protection

Agency, Office of Pesticide Programs, Environmen tal Fate and Effects Division.

December 2006.

USEPA. 20 07. Kaul, M. Maximum Number of Crop Cycles per Year in California for Methomyl

Use Sites. U.S. Environmental Protection Agency, Office of Prevention, Pesticide s, and

Toxic Substances

, Biological and Economic Analysis Division. Memorandum to the

Environment al Fate and Effects Division . Feb. 28 , 200 7

.

USEPA. 2008. Dean, R. and J. Angier. Registration Review

– Preliminary Problem Formulation

for the Ecological Risk Assessment of Clethodim. DP barcode 349758. U.S.

Environmental Protection Agency, Office of Pesticide Programs, Environmental Fate and

Effects Division. M emorandum to the Special Review and Reregistration Division. Aug.

13, 2008.

USEPA. 2009. Guidance for Selecting Input Parameters in Modeling the Environmental Fate and

Transport of Pesticides. Version 2.1

. U.S. Environmental Protection Agency, Office of

Pesticide Programs, Environmental Fate and Effects Division. Oct. 22, 2009.

http://www.epa.gov/oppefed1/models/water/input_parameter_guidance.htm

USEPA. 2012. Clethodim (1 21011): Screening Level Usage Analysis (SLUA). U.S.

Environmental Protection Agency, Office of Pesticide Programs, Biological and

Economic Analysis Division. Sep. 6, 2012.

6.1. Ecotoxicity Studies

71

- 1 Avian Single Dose Oral Toxicity

MRID Citation Refe rence

40974525 Hinken, C.; Grimes, J. (1986) RE

- 45601 Technical (SX

- 1688): An Acute Oral Toxicity Study

with the Bobwhite: Project ID: S

- 2830. Unpublished study prepared by Wildlife International

Ltd. 63 p.



## 71

- 2 Avian Dietary Toxicity

MRID Citation Reference

40974526 Hinken, C.; Grimes, J. (1986) RE

- 45601 Technical (SX

- 1688): A Diet

- ary LC50 Study with the

Bobw hite: Project ID: S

- 2832. Unpu blished study prepared by Wildlife International Ltd. 48 p.

40974527 Hinken, C.; Grimes, J.; Jaber, M. (1986) RE

- 45601 Technical (SX

- 1688): A Dietary LC50

Study with the Mallard: Project ID: S

- 2831. Unpublished study prepared by Wildlife

International Ltd. 54 p.



## 71

- 4 Avian Reproduction

MRID Citation Reference

41030205 Beavers, J. (1988) RE

- 45601 Technical: A One

- generation Reproduction Study with the Mallard

(Anas platyrhynchos): Project ID S

- 28

- 37. Unpublished study prepared by Wildlife

## 66 International, Ltd. 155 p.



## 72

- 1 Acute Toxicity to Freshwater Fish

MRID Citation Reference

40974528 Swigert, J. (1986) Acute Toxicity of Chevron RE

- 45601 Technical to Rainbow Trout in a Static

Test System: Project ID: S

- 2838. Un

- published study prepared by ABC Laboratories, Inc. 50 p.

40974529 Swigert, J. (1986) Acute Toxicity of Chevron RE

- 45601 Technical to Bluegill Sunfish in a Static

Test System: Project ID: S

- 2839. Unpublished study prepared by ABC Laboratories, Inc. 50 p.



## 850.1075 Fish acute toxicity test, freshwater and marine

MRID Cita tion Reference

48104304 Bidinotto, P. (2003) Acute Toxicity of Clethodim Agan Technical to Fish Danio rerio: Final

Report. Project Number: 90005085, RF/0409/208/099/02. Unpublished study prepared by

BIOAGRI Laboratorios, Ltda. 59 p.

48417002 Palmer, S.; Kendall, T.; Krueger, H. (2011) Clethodim: A 96

- Hour Static Renewal Acute

Toxicity Test wtih the Fathead Minnow (Pimephales promelas). Project Number: 201100054,

263A/121, VP/37738. Unpublished study prepared by Wildlife International, Ltd. 57 p.

484 17003 Palmer, S.; Kendall, T.; Krueger, H. (2011) Clethodim: A 96

- Hour Static

- Renewal Acute

Toxicity Test with the Rainbow Trout (Oncorhynchus mykiss). Project Number: 201100055,

263A/122, VP/37733. Unpublished study prepared by Wildlife International, Ltd . 55 p.

48417004 Palmer, S.; Kendall, T.; Krueger, H. (2011) Clethodim: A 96

- Hour Static

- Renewal Acute

Toxicity Test with the Sheepshead Minnow (Cyprinodon variegatus). Project Number:

201100057, 263A/124, VP/37743. Unpublished study prepared by Wildlife International, Ltd.

53 p.



## 72

- 2 Acute Toxicity to Freshwater Invertebrates

MRID Citation Reference

40974530 Forbis, A. (1986) Acute Toxicity of Chevron RE

- 45601 Technical to Daphnia magna in a Static

S ystem: Project ID: S

- 2835. Unpu blished study prepared by ABC Laboratories, Inc. 49 p.

41685101 Burgess, D.; Blasberg, J.; Stuerman, L. (1990) Acute Toxicity of Select 2EC to Daphnia magna:

Lab Project Number: 38601: 89

- 437: 6065. Unpublished study prepared by Analytical Bio

chemistry Laboratories, Inc. 53 p.



## 850.10 3 5 Mysid acute toxicity test

MRID Citation Reference

48417001 Palmer, S.; Kendall, T.; Krueger, H. (2011) Clethodim: A 96

- Hour Static

- Renewal Acute

Toxicity Test with the Saltwater Mysid (Americamysis bahia). Project Number: 201100056,

263A/123, VP/37741. Unpublished study prepared by Wildlife International, Ltd. 55 p.



## 72

- 3 Shellfish Acute

MRID Citation Reference

48563001 Palmer, S.; Kendall, T.; Gallagher, S. (2011) Clethodim: A 96

- Hour Shell Deposition Test with

the Eastern Oyster (Crassostrea virginica). Project Number: 263A/125 VP/37748. Unpublished

study prepared by Wildlife International, Ltd. 60p.

## 67 72

- 4 now 850.1400 Fish Early Life Stage/Aquatic Invertebrate Life Cycle Study

MRID Citation Reference

48104303 Bidinotto, P. (2003) Chronic Toxicity of Clethodim Agan Technical to Fish, Early

- Life Stage:

Final Report. Project Number: RF/0409/217/002/02, 90005087. Unpublished study prepared by

BIOAGRI Laboratorios, Ltda. 68 p.



## 72

- 4 now 850.1 3 0 0 Daphnid chronic toxicity test

MRID Citation Reference

48104305 Muniz, T. (2002) Chronic Toxicity of Clethodim Agan Technical to Daphnia magna: Final

Report. Project Number: 90005084, RF/0409/207/032/02. Unpublished study prepared by

BIOAGRI Laboratorios, Ltda. 73 p.



## 72

- 4 Mysid chronic reproduction test

MRID Citation Reference

No acceptable data



## 81

- 1 Acute oral toxicity in rats

MRID Citation Reference

40974507 Easter, M. (1986) The Acute Oral Toxicity of RE

- 45601 Technical (SX

- 1688) in Adult Male and

Female Rats: Project ID: S

- 2764. Unpublished study prepared by Chevron Environmental Health

Center, Inc. 71 p.



## 81

- 3 Acute inhalation toxicity in rats

MRID C itation Reference

40974512 Bruce, E. (1986) The Acute Inhalation Toxicity of RE

- 45601 Technical (SX

- 1688) in Rats:

Project ID: S

- 2783. Unpublished study prepared by Chevron Environmental Health Center, Inc.

46 p.



## 83

- 4 2

- generation repro.

- rat

MRID Citation Reference

41030119 MacKenzie, K. (1986) Final Report: Pilot Rat Reproduction Study with Chevron RE

- 45601

Technical: Project ID S

- 2758. Unpublished study prepared by Hazleton Laboratories America,

Inc. 235 p.

41030120 Tellone, C. (1987) Two Generation (One Litter) Reproduction Study in Rats with RE

- 45601

Technical: Project ID S

- 2778. Unpublished study prepared by Chevron Environmental Health

Center, Inc. 2218 p.



## 122

- 1 Seed Germination/Seedlin g Emergence and Vege tative Vigor

MRID Citation Reference

41685102 Maggio, R. (1990) Tier I Seed Germination/Seedling Emergence Non

- target Phytotoxicity

Study Using Select (Clethodim): Lab Project Number: LR 89

- 54B. Unpublished study prepared

## 68 by Pan

- Agricul

- ture Laboratories, Inc. 126 p.

41685103 Maggio, R. (1990) Tier I Vegetative Vigor Nontarget Phytotoxicity Study Using Select

(Clethodim): Lab Project Number: LR 89

- 54A. Unpublished study prepared by Pan

Agricultural Laboratories, Inc. 102 p.

ACC 9011861 Rose, A.F. 1990. Nontarget Vegetative V igor Study with SELECT 2EC Herbicide



## 123

- 1 Seed germination/seedling emergence and vegetative vigor

MRID Citation Reference

41685104 Chetram, R. (1990) Tier 2 Seed Germination/Seedling Emergence Non

- target Phytotoxicity

Study Using Select (Clethodim): Lab Project Number: LR 89

- 55B. Unpublished study prepared

by Pan

- Agricul

- tural Laboratories, Inc. 149 p.

41685105 Chetram, R. (1990) Tier 2 Vegetative Vigor Nontarget Phytotoxicity Study Using Select

(Clethodim): Lab Project Number: LR 89

- 55A. Unpublished study prepared by Pan

Agricultural Laboratories, Inc. 121 p.



## 123

- 2 Aquatic plant growth

MRID Citation Reference

41685106 Forbis, A.; Blasberg, J. (1990) Acute Tox icity of RE

- 45601 Tech nical to the Freshwater Algae

(Selenastrum capricornutum) Printz: Lab Project Number: 38373: 89

- 404. Unpublished study

prepared by Analytical Bio

- chemistry Laboratories, Inc. 60 p.

42029701 Rhodes, J.; Hughes, J. (1991) The Phytotoxicity of RE

- 45601 Technical with Duckweed

(Lemna gibba G3) in a Static System: Lab Project Number: B765

- 01

- 1: 38621. Unpublished

study prepared by Malcolm Pirnie, Inc. and ABC Labs, Inc. 77 p.

42029702 T hopmpson, S.; Holmes, C.; Peters, G. (1991) Select 2.0 EC: A 14

- Day Toxicity Test with

Duckweed (Lemna gibba G3): Lab Project Number: 162A

- 117. Unpublished study prepared by

Wildlife Inter

- national, Inc. 51 p.

42029703 Grimstead, S.; Holmes, C.; Peters, G. (1991) Select 2 EC: A 5

- Day Toxicity Test with the

Freshwater Alga (Selenastrum capricornutum): Lab Project Number: 162A

- 121. Unpublished

study pre

- pared by Wildlife International, Ltd. 48 p.

42029704 Grimes, J.; Th ompson, S.; Holmes, C. (1991) Select 2.0 EC: A 5

- Day Toxicity Test with the

Marine Diatom (Skeletonema costatum): Lab Project Number: 162A

- 120. Unpublished study

prepared by Wildlife International Ltd. 51 p.

42029705 Thompson, S.; Holmes, C.; Peters, G. (1991) Select 2.0 EC: A 5

- Day Toxicity Test with the

Freshwater Alga (Anabaena flos

- aquae): Lab Project Number: 162A

- 119A. Unpublished study

prepared by Wildlife International Ltd. 53 p.

42029706 Thompson, S.; Holmes, C.; Peters, G. (1991) Select 2.0 EC: A 5

- Day Toxicity Test with the

Freshwater Diatom (Navicula pelliculosa): Lab Project Number: 162A

- 118. Unpublished study

prepared by Wildlife International Ltd. 52 p.

E065938 Ma J., L. Xu, S. Wang, R. Zheng, S. Jin, S. Huang, Y. Huang. 2002. Toxicity of 40 Herbicides

to the Green Alga Chlorella vulgaris . Ecotoxicology and Environmental Safety 51: 128

- 132.

E083543 Ma J., S. Wang, P. Wang, L. Ma, X. Chen, and R. Xu. 2006. Toxicity Assessment of 40

Herbicides to the Green Alga Raphidocelis subcapitata . Ecotoxicology and Environmental

Safety 63: 456

- 462.

## 69 141

- 1 Honey bee acute contact

MRID Citation Reference

40974532 Atkins, E. (1986) Bee Adult Toxicity Dusting Test(BATDT) Evaluating the Comparative Acute

Contact Toxicity of RE

- 45601; 9433

- 16, 87.9% Technical (Select) to Honey Bee Worker

Adults: Project ID: Test 439. Unpublished study prepared by Universi ty of California, Riverside.

53 p.

41685107 Hoxter, K.; Smith, G. (1990) Select 2. 0 EC: An Acute Contact Toxicity Study with the Honey

Bee: Lab Project Number: 263

- 120. Un

- published study prepared by Wildlife International Ltd.

66 p.



## 165

- 4 Bioaccumulation in fish

MRID Citation Reference

40974524 Rose, A.; Suzuki, J. (1988) Characterization of |carbon 14| Residues in Bluegill Sunfish Treated

with (Allyl

- 2

- |Carbon 14|

- Clethodim or (Cyclohexene

- 1

- One

- 4,6

- ?carbon 14|)

- Clethodim: Pro

ject ID: MEF

- 0020. Unpublished study prepared by Chevron Chemi

- cal Co. 109 p.

40974531 Forbis, A. (1987) Uptake, Depuration and Bioconcentration of Allyl

- 2 |carbon| and

Cyclohexene

- 1

- One

- 4,6|carbon| RE

- 45601 to Bluegill Sunfish (Lepomis macrochirus): Project

ID: S

- 2827. Un

- published study prepared by ABC Laboratories, Inc. 87 p.



## 6.2. Environmental Fate and Product Chemistry Studies

MRID Citation Reference

40974520 Pack, D. (1988) Hydrolysis Study on RE

- 45601: Project ID: MEF

- 0013/ 8703899. Unpublished

study prepared by Chevron Chemical Co. 52 p.

40974522 Pack, D. (1988) The Aerobic Soil Metabolism of ?Propyl

- 1

- ?carbon 14|Clethodium: Project ID:

MEF/0014/8721028. Unpublished study prepared by Chevron Chemical Co. 54 p.

40974523 Pack, D. (1988) Freundlich Soil Adsorption/Desorption Coefficients of Clethodi m and Three

Metabolites: Project ID: MEF

- 0102/ 8829844. Unpublished study prepared by Chevron Chemical

Co. 122 p.

40974524 Rose, A.; Suzuki, J. (1988) Characterization of |carbon 14| Residues in Bluegill Sunfish Treated

with (Allyl

- 2

- |Carbon 14|

- Clethod im or (Cyclohexene

- 1

- One

- 4,6

- ?carbon 14|)

- Clethodim: Pro

ject ID: MEF

- 0020. Unpublished study prepared by Chevron Chemi

- cal Co. 109 p.

40974531 Forbis, A. (1987) Uptake, Depuration and Bioconcentration of Allyl

- 2 |carbon| and Cyclohexene

1

- One

- 4,6|carbon| RE

- 45601 to Bluegill Sunfish (Lepomis macrochirus): Project ID: S

- 2827. Un

published study prepared by ABC Laboratories, Inc. 87 p.

41030133 Chen, Y. (1988) Allyl

- 2

- Carbon 14|

- Clethodim Photodegradation in Water: Project ID MEF

0025. Unpublished study prepared by Chev

- ron Chemical Co. 93 p.

41030134 Chen, Y. (1988) 4,6

- Ring

- Carbon 14|

- Clethodim Photodegradation in Water: Project ID MEF

0024. Unpublished study prepared by Chev

- ron Chemical Co. 97 p.

41030135 Chen, Y. (1988) Clethodim Photodegradation on Soil: Project ID MEF

- 0022. Unpublished study

prepared by Chevron Chemical Co. 44 p.

41030207 Ho, B. (1989) Field Dissipation Study with Clethodim on Cotton in Mississippi

-- T7227: Project

## 70 MRID Citation Reference

ID 1641

- 88

- 7227. Unpublished study prepared by Chevron Chemical Co. 512 p.

41030208 Ho, B. (1989) Field Dissipation Study with Clethodim on Cotton in California

-- T7226: Project ID

1641

- 88

- 7226. Unpublished study prepared by Chevron Chemical Co. 427 p.

41030209 Ho, B. (1989) Field Dissipation Study with Clethodim on Soybean in North Caro lina

-- T7229:

Project ID 1641

- 88

- 7229. Unpublished study prepared by Chevron Chemical Co. 501 p.

41030210 Ho, B. (1989) Field Dissipation Study with Clethodim on Soybean in Iowa

-- T7228: Project ID

1641

- 88

- 7228. Unpublished study prepared by Chevron Chemic al Co. 536 p.

41376801 Pack, D. (1990) The Aerobic Soil Metabolism of Clethodim Using ?Ring

- 4,6

- (Carbon 14)|

- and

?Allyl

- 2

- (Carbon 14)|

- Clethodim Revised January 5, 1990: Lab Project ID: MEF

0015/0016/8914823. Unpublished study prepared by Chevron Chemic al Co. 161 p.

41652301 Tucker, B. (1990) The Anaerobic Aquatic Metabolism of Ring

- 4,6

- ?carbon 14||Clethodim: Lab

Project Number: MEF

- 0141/9004983. Unpublished study prepared by Chevron Chemical Co. 85

p.

45591605 Hiscock, A., R. Warren, and B. Patterson. A Small

- Scale Prospective Groundwater Monitoring

Study for Oxamyl. DuPont Report No. AMR 4318

- 97. Unpublished study conducted by Stone

Environmental, Inc., Ecologic, Inc., Agricultural Systems Associates, AGVISE Laboratories,

Centre Analytical L aboratories, Inc., and E.I. du Pont de Nemours and Company; submitted by

E.I. du Pont de Nemours and Company, Wilmington, DE. Jan. 14, 2002.

48881401 Gregory, A. (2012) Clethodim TGAI: Summary of Product Properties Test Guidelines. Project

Number: ALB12/14. Unpublished study prepared by Albaugh, Inc. 8p.

48881405 Li, H. (2012) Chemical and Physical Characterization of Clethodim TGAI: Color, Physical State,

Odor, Stability, pH, Oxidation/Reduction, UV

- Vis, Boiling Point, Density, Viscosity,

Dissocia tion Constant, Partition Coefficient and Solubility: Final Report. Project Number:

NC/2011/083. Unpublished study prepared by Nutrichem Laboratory Co., Ltd. 87p.

## 71 APPENDIX A

. Aquatic Model Input/Output Files

## 72 A PPENDIX B

. Sample T

- REX

, and TerrPlant Inputs/ Outputs for Clethodim

T

- REX

Acute and Chronic RQs are based on the Upper Bound

Kenaga Residues.

Chemical Name: The maximum single day residue estimation is used for

Use both the acute and reproduction RQs.

Formulation

Application Rate 0.25 lbs a.i./acre RQs reported as "0.00" in the RQ tables below should be noted as

Half-life 35 days <0.01 in your assessment. This is due to rounding and significant

Application Interval 7 days figure issues in Excel.

Maximum # Apps./Year 18

Length of Simulation 1 year

Variable application rates? no

Bobwhite quail LD50 (mg/kg-bw) 2000.00

Mallard duck) LC50 (mg/kg-diet) 3978.00

Mallard duck NOAEL(mg/kg-bw) 0.00

Mallard duck NOAEC (mg/kg-diet) 833.00

1360.00

0.00

51.00

500.00

Kenaga

Values

Short Grass 425.28

Tall Grass 194.92

Broadleaf plants 239.22

Fruits/pods/seeds 26.58

Arthropods 166.57 Endpoints Upper Bound Kenaga Residues For RQ Calculation

Dietary-based EECs (ppm) NOAEL (mg/kg-bw)

NOAEC (mg/kg-diet) Mammals LD50 (mg/kg-bw)

LC50 (mg/kg-diet) clethodim

fallow land, golf course turf, non-cropped

areas; alfalfa (2 apps with 9 cuttings/yr =

18 apps/yr)

0

Avian Questions?

Comments?

Click here

Avian Results

Avian Body Ingestion (Fdry) Ingestion (Fwet) % body wgt FI

Class Weight (g) (g bw/day) (g/day) consumed (kg-diet/day)

Small 20 5 23 114 2.28E-02

Mid 100 13 65 65 6.49E-02

Large 1000 58 291 29 2.91E-01

20 5 5 25 5.06E-03

Granivores 100 13 14 14 1.44E-02

1000 58 65 6 6.46E-02

Avian Body Adjusted LD50

Weight (g) (mg/kg-bw)

20 1440.86

100 1834.29

1000 2591.00

small mid large

20 100 1000

Short Grass 484.35 276.20 123.66

Tall Grass 221.99 126.59 56.68

Broadleaf plants 272.45 155.36 69.56

Fruits/pods 30.27 17.26 7.73

Arthropods 189.70 108.18 48.43

Seeds 6.73 3.84 1.72

20 100 1000

Short Grass 0.34 0.15 0.05

Tall Grass 0.15 0.07 0.02

Broadleaf plants 0.19 0.08 0.03

Fruits/pods 0.02 0.01 0.00

Arthropods 0.13 0.06 0.02

Seeds 0.00 0.00 0.00

Dietary-based RQs

Acute Chronic

Short Grass 0.11 0.51

Tall Grass 0.05 0.23

Broadleaf plants 0.06 0.29

Fruits/pods/seeds 0.01 0.03

Arthropods 0.04 0.20

Note: To provide risk management with the maximum possible information,

it is recommended that both the dose-based and concentration-based

RQs be calculated when data are available Dose-based EECs

(mg/kg-bw) Avian Classes and Body Weights (grams)

Dose-based RQs

(Dose-based EEC/adjusted LD50)

RQs Avian Acute RQs

Size Class (grams)

## 73 clethodim fallow land, golf course turf, non-cropped areas; alfalfa (2 ap Upper bound Kenaga Residues



### Mammalian Results

Mammalian Body Ingestion (Fdry) Ingestion (Fwet) % body wgt FI

Class Weight (g bwt/day) (g/day) consumed (kg-diet/day)

15 3 14 95 1.43E-02

Herbivores/ 35 5 23 66 2.31E-02

insectivores 1000 31 153 15 1.53E-01

15 3 3 21 3.18E-03

Grainvores 35 5 5 15 5.13E-03

1000 31 34 3 3.40E-02

Mammalian Body Adjusted Adjusted

Class Weight LD50 NOAEL

15 2989.05 112.09

Herbivores/ 35 2418.46 90.69

insectivores 1000 1046.06 39.23

15 2989.05 112.09

Granivores 35 2418.46 90.69

1000 1046.06 39.23

15 35 1000

Short Grass 405.47 280.23 64.97

Tall Grass 185.84 128.44 29.78

Broadleaf plants 228.08 157.63 36.55

Fruits/pods 25.34 17.51 4.06

Arthropods 158.81 109.76 25.45

Seeds 5.63 3.89 0.90

15 grams 35 grams 1000 grams

Acute Chronic Acute Chronic Acute Chronic

Short Grass 0.14 3.62 0.12 3.09 0.06 1.66

Tall Grass 0.06 1.66 0.05 1.42 0.03 0.76

Broadleaf plants 0.08 2.03 0.07 1.74 0.03 0.93

Fruits/pods 0.01 0.23 0.01 0.19 0.00 0.10

Arthropods 0.05 1.42 0.05 1.21 0.02 0.65

Seeds 0.00 0.05 0.00 0.04 0.00 0.02

Acute Chronic

Short Grass #DIV/0! 0.85

Tall Grass #DIV/0! 0.39

Broadleaf plants #DIV/0! 0.48

Fruits/pods/seeds #DIV/0! 0.05

Arthropods #DIV/0! 0.33

Note: To provide risk management with the maximum possible information,

it is recommended that both the dose-based and concentration-based

RQs be calculated when data are available 

### Dose-Based EECs

(mg/kg-bw) (grams) Mammalian Classes and Body weight



## Dietary-based RQs

(Dietary-based EEC/LC50 or

NOAEC) Mammal RQs Medium mammal Large mammal 

## Dose-based RQs

(Dose-based EEC/LD50 or

NOAEL) Small mammal

## 74 TerrPlant

TerrPlant v. 1.2.2

Green values signify user inputs (Tables 1, 2 and 4).

Input and output guidance is in popups indicated by red arrows.

Chemical Name

PC code

Use

Application Method

Application Form

Solubility in Water (ppm)

Input Parameter Symbol Value Units

Application Rate A 0.25 lbs ai/A

Incorporation I 1 none

Runoff Fraction R 0.02 none

Drift Fraction D 0.05 none

Equation EEC

(A/I)*R 0.005

(A/I)*R*10 0.05

A*D 0.0125

((A/I)*R)+(A*D) 0.0175

((A/I)*R*10)+(A*D) 0.0625

Plant type EC 25 

### NOAEC EC 25 

### NOAEC

Monocot 0.0076 0.0004 0.003 0.0023

Dicot 0.25 0.25 0.25 0.25

Plant Type Listed Status Dry Semi-Aquatic Spray Drift

Monocot non-listed 2.30 8.22 4.17

Monocot listed 43.75 156.25 5.43

Dicot non-listed <0.1 0.25 <0.1

Dicot listed <0.1 0.25 <0.1 Description

Total for semi-aquatic areas Table 1. Chemical Identity.

Clethodim

Max. Single app. (fallow land, golf course turf, noncroped areas, etc)

Table 2. Input parameters used to derive EECs. Aerial

Liquid

29 121011

Table 3. EECs for Clethodim. Units in lbs ai/A.

Runoff to dry areas

Runoff to semi-aquatic areas

Spray drift

Total for dry areas

*If RQ > 1.0, the LOC is exceeded, resulting in potential for risk to that plant group. Vegetative Vigor Seedling Emergence

Table 5. RQ values for plants in dry and semi-aquatic areas exposed to Clethodim through runoff

and/or spray drift.* Table 4. Plant survival and growth data used for RQ derivation. Units are in lbs ai/A.

## 75 TerrPlant v. 1.2.2

Green values signify user inputs (Tables 1, 2 and 4).

Input and output guidance is in popups indicated by red arrows.

Chemical Name

PC code

Use

Application Method

Application Form

Solubility in Water (ppm)

Input Parameter Symbol Value Units

Application Rate A 0.045 lbs ai/A

Incorporation I 1 none

Runoff Fraction R 0.02 none

Drift Fraction D 0.05 none

Equation EEC

(A/I)*R 0.0009

(A/I)*R*10 0.009

A*D 0.00225

((A/I)*R)+(A*D) 0.00315

((A/I)*R*10)+(A*D) 0.01125

Plant type EC 25 

### NOAEC EC 25 

### NOAEC

Monocot 0.0076 0.0004 0.003 0.0023

Dicot 0.25 0.25 0.25 0.25

Plant Type Listed Status Dry Semi-Aquatic Spray Drift

Monocot non-listed 0.41 1.48 0.75

Monocot listed 7.88 28.13 0.98

Dicot non-listed <0.1 <0.1 <0.1

Dicot listed <0.1 <0.1 <0.1 Table 3. EECs for Clethodim. Units in lbs ai/A.

Runoff to dry areas

Runoff to semi-aquatic areas

Spray drift

Total for dry areas

*If RQ > 1.0, the LOC is exceeded, resulting in potential for risk to that plant group. Vegetative Vigor Seedling Emergence

Table 5. RQ values for plants in dry and semi-aquatic areas exposed to Clethodim through runoff

and/or spray drift.* Table 4. Plant survival and growth data used for RQ derivation. Units are in lbs ai/A. Description

Total for semi-aquatic areas Table 1. Chemical Identity.

Clethodim

Lowest app. Rate (field corn)

Table 2. Input parameters used to derive EECs. Aerial

Liquid

29 121011

## 76 APPENDIX C

. Summary of Toxicity Endpoints and Study Classifications for Clethodim

TAXON ENDPOINT FORMULATION MRID STUDY

CLASS

IFICATION COMMENTS

FRESHWATER FISH

Acute

Rainbow trout

( Oncorhynchus

mykiss ) 96

- hr LC 50 

### = 24.4 mg a.i./L

(slightly toxic) TGAI (83.3%) 40974528 Acceptable Sublethal effects observed

were surfacing, loss of

equilibrium, dark

discoloration, fish on the

bottom of the test chamber

and/or quiescence at 32, 56,

and 100 mg/L (nominal) the

only test levels measured were

levels 1 (10 mg/L = 7.8 mg

a.i./L), level 3 (32 mg/L = 18

mg a.i./L), and level 5 (100

mg/L = 33 mg a.i./L),

representing nominal and the

mean

- measured concentrations

of that test level , respectively

.

Rainbow trout

( Oncorhynchus

mykiss ) 96

- hr LC 50 

### > 110

mg a.i./L

(practically non

toxic) TGAI ( 95.4 %) 

## 4841700 3 Acceptable Sublethal effects observed

were lethargy, lying on the

bottom, and loss of

equilibrium.

Bluegill

sunfish

( Lepomis

macrochirus ) 96

- hr LC 50 

### > 33

mg a.i./L

(slightly toxic) TGAI (83.3%) 40974529 Acceptable S ublethal effects (surfacing

and/or gulping air) were

observed at in one chamber of

the 100 mg/L (33 mg a.i./L

-

mean

- measured) test level at

96 hours. O nly test levels

mea sured were levels 1 (10

mg/L = 8 .8 m g a.i./L), level 3

(32 mg/L = 20 mg a.i./L), and

level 5 (100 mg/L = 33 mg

a.i./L), representing nominal

and the mean

- measured

concentrations of that test

level , respectively

.

Fathead

minnow

( Pimephales

promelas ) 96

- hr LC 50 

### = 110

mg a.i./L

(practically non

toxic) TGAI (95.4%) 

## 48417002 Acceptable Sublethal effects observed

were lethargy, surfacing, lying

on the bottom, and swollen

abdomen at 55 and 115 mg

a.i./L.

Zebrafish

( Danio rerio ) 96

- hr LC 50 

### = 133

mg a.i./L

(practically non

toxic) TGAI (95.7%) 48104304 Supplemental Mortality only, s ublethal

effects were not reported.

## 77 TAXON ENDPOINT FORMULATION MRID STUDY

CLASS

IFICATION COMMENTS

Chronic

Fathead

minnow

( Pimephales

promelas ) NOAEC = 0.010

mg a.i./L

LOAEC = 0.031

mg a.i./L TGAI (9 5

. 7 %) 48104303 Supplemental LOAEC based on reduced

survival. Test concentrations

were not measured; therefore

the results were adjusted for

purity of the technical grade

material (95.7%). Time to

hatch, hatching success, and

post

- hatch survival were not

evaluated ; effects on

reprod uction were not

measured in this study

.

Rainbow trout

( Oncorhynchus

mykiss ) ACR derived

NOAEC = 0.002

mg a.i./L NA NA NA Rainbow trout acute toxicity

endpoint was the most

sensitive, the fathead minnow

acute and chronic toxicity data

were used to estimate a

NOAEC for the rainbow trout.

[(Fathead LC50/ NOAEC) =

ACR; (RT LC50/ACR) =

0.002 mg a.i./L ]

ESTUARINE/MARINE FISH

Acute

Sheepshead

Minnow

( Cyprinodon

variegates ) 96

- hr LC 50 

### > 124

mg a.i./L

(practically non

toxic) TGAI (95.4%) 48417004 Acceptable No Mortality or sublethal

effects were observed.

Chronic

No acceptable estuarine/marine fish chronic toxicity data is available for clethodim ; therefore the estimated freshwater fish

NOAEC value for rainbow trout was used as a conservative estimate of potential toxicity to estuarine/marine fish (NOAEC =

0.002 mg a.i./L ).

FRESHWATER INVERTEBRATES

Acute

Water flea

( Daphnia

magna ) 48

- hr EC 50 

### = 20.2

mg a.i./L

(slightly toxic) EP (25.6%) 41685101 Acceptable No Mortality or sublethal

effects were observed.

Chronic

Water flea

( Daphnia

magna ) NOAEC = 0.94

mg a.i./L

LOAEC = 3.0 mg

a.i./L TGAI (95.7%) 48104305 Supplemental Based on offspring production

per female and total length of

surviving adults. Survival and

treatment

- related delay in time

to first brood released was

observed at the 9.3 mg a.i./L

treatment level.

ESTUARINE/MARINE INVERTEBRATES

Acute

Eastern oyster

( Crassostrea

virginica ) 96

- hr EC 50 

### = 5.3

mg a.i./L 1



### (moderately toxic) TGAI (95.4%) 48563001 Supplemental R eductions in shell deposition

at all treatment levels relative

to the negative control.

## 78 TAXON ENDPOINT FORMULATION MRID STUDY

CLASS

IFICATION COMMENTS

Mysid Shrimp

( Americamysis

bahia ) 96

- hr EC 50 

### = 33

mg a.i./L

(slightly toxic) TGAI (95.4%) 48417001 Acceptable M ortality and sublethal effects

were observed . Sublethal

effects included lethargy,

surfacing, lying on the bottom

of the test and chamber at 28,

56, and 166 mg a.i./L.

Chronic

No acceptable estuarine/marine invertebrate chronic toxicity data is available for clethodim ; therefore the freshwater

invertebrate NOAEC value for daphnid was used as a conservative estimate of potential toxicity to estuarine/marine

invertebrate (NOAEC = 0.94 mg a.i./L ).

AQUATIC PLANTS

Non

- Vascular

Marine Diatom

( Skeletonema

costatum ) 120 hr EC 50 

### = 8.6

mg a.i./L

NOAEC = 5.4 mg

a.i./L EP ( 25.6% ) 42029704 Acceptable 

## Inhibition of growth rate

based on cell counts after 5

days (120 hours).

Green algae

( Selenastrum

capricornutum ) 120 hr EC 50 

### > 11.4

mg a.i./L

NOAEC = 11.4

mg a.i./L TGAI ( 83.3% ) 41685106 Acceptable 

## No effects

Green algae

( Selenastrum

capricornutum ) 5d EC 50 

### = 19.5 mg

a.i./L

NOAEC = 11.1

mg a.i./L EP ( 25.6% ) 42029703 Acceptable 

## Inhibition of growth rate

based on cell counts after 5

days (120 hours).

Blue

- green

algae

( Anabeana flos

aquae ) 5d EC 50 

### = 16.7 mg

a.i./L

NOAEC = 5.6 mg

a.i./L EP ( 25.6% ) 42029705 Acceptable 

## Inhibition of growth rate

based on cell counts after 5

days (120 hours).

Freshwater

diatom

( Navicula

pelliculosa ) 120 hr EC 50 

### = 11.0

mg a.i./L

NOAEC = 3.1 mg

a.i./L EP ( 25.6% ) 42029706 Acceptable 

## Inhibition of growth rate

based on cell counts after 5

days (120 hours).

Green algae

( Chlorella

vulgaris ) 96 hr EC 50 

### = 4.6

mg a.i./L EP (12%) E065938;

Ma et al

.,

2002 Qualitative

(Open

Literature) 

## Inhibition in growth rate

based on cell counts after

96 hours.

Green algae

( Raphidocelis

subcapitata ) 96 hr EC 50 

### = 2.7

mg a.i./L EP (12%) E083543;

Ma et al

.,

2006 Qualitative

(Open

Literature) 

## Inhibition in growth rate

based on cell counts after

96 hours.

Vascular

Duckweed

( Lemna gibba ) 14

- day EC 50 

### = 1.34

mg a.i./L

NOAEC = 0.37

mg a.i./L TGAI (82.4%) 42029701 Acceptable Percent inhibition based on

mean frond counts on day 14

.

Duckweed

( Lemna gibba ) 14d EC 50 

### = 42.5

mg a.i./L

NOAEC = 1.1 mg

a.i./L EP (25.6%) 42029702 Supplemental Percent inhibition based on

mean frond counts on day 14

.

## 79 TAXON ENDPOINT FORMULATION MRID STUDY

CLASS

IFICATION COMMENTS

BIRDS

Acute Oral

Bobwhite quail

( Colinus

virginianus ) 14

- day > 2000 mg

a.i./kg

- bw

(practically non

toxic) TGAI (82%) 40974525 Acceptable NOAEL = 1250 mg a.i./kg

- bw

based on overt signs (lethargy,

wing droop and ruffled

appearance) of toxicity and a

reduction in weight gain at

1650 mg a.i./kg

- bw.

Sub

- Acute Dietary

Bobwhite quail

( Colinus

virginianus ) 8

- day LC 50 

### > 4270

mg a.i./kg

- diet

(practically non

toxic) TGAI (82%) 4097452 6 Acceptable N o mortality or signs of

toxicity were observed.

Mallard duck

( Anas

platyrhynchos ) 8

- day LC 50 

### > 3978

mg a.i./kg

- diet

(practically non

toxic) TGAI (82%) 4097452 7 Acceptable N o mortality or signs of

toxicity were observed.

Chronic

Bobwhite quail

( Colinus

virginianus ) No Valid Data

Available TGAI ( 83.3 %) 41030206 Unacceptable/

Invalid A high rate of adult mortality

in both control and test

subjects were not adequately

e xplained, it is not clear if the

deaths were due to the test

chemical, poor husbandry,

random error, or a

combination of these factors.

This study was downgraded to

unac ceptable/invalid.

Mallard duck

( Anas

platyrhynchos ) 19

- wk NOAEC =

833 mg a.i./kg

- diet

LOAEC > 833 mg

a.i./kg

- diet TGAI ( 83.3 %) 41030205 Acceptable No effects on mortality,

behavior, growth or

reproduction.

MAMMALS

Acute

Rat

( Rattus

norvegicus ) LD 50 

### = 1360

mg/kg

- bw

(slightly toxic) TGAI (83.3%) 40974507 Acceptable Acute oral; Signs of toxicity

that were observed included

salivation, motor activity,

unsteady gait, hyperreactivity,

lacrimation, diarrhea, red nasal

discharge, red or clear ocular

discharge, clonic convulsions,

and/or collapse on the day of

dosing. Reduced food

consumption and yellow

anogenital stains were

observed in the surviving rats

in all treated groups.

## 80 TAXON ENDPOINT FORMULATION MRID STUDY

CLASS

IFICATION COMMENTS

Rat

( Rattus

norvegicus ) LC 50 

### > 3.9 mg/L TGAI ( 83.3 %) 40974512 Supplemental Acute inhalation; 4

- hr

exposure; there were no

deaths. Clinical signs of

toxicity included squinted or

closed eyes, colorless eye

discharge, salivation, red nasal

discharge, abnormal

respiratory sounds, decreased

feces, unkempt appearance,

and a yellow/red anogenital

discharge.

Chronic

Rat

( Rattus

norvegicus ) NOAEC = 500

mg/kg

- diet (51

mg/kg

- bw/day)

LOAEC = 2500

mg/kg

- diet (263

mg/kg

- bw/day) TGAI (82.3%) 41030120 Acceptable Decreased body weight and

food consumption in parental

organisms, NO reproductive

effects at up to 2500 ppm

( approx. 263 mg/kg

- bw/day).

TERRESTRIAL INVERTEBRATES

Honey Bee

( Apis mellifera ) LD 50 

### >100 μ g

a.i./bee

(practically non

toxic) (EP 26% a.i.) 41685107 Acceptable 22% mortality in the 100 μ g

a.i./bee dose group; signs of

toxicity were not observed in

dose groups less than 100 μ g

a.i./bee; the no

- effect dose was

60 μ g a.i./bee

. TERRESTRIAL PLANTS

DICOTS

All Dicots

tested Seedling

emergence EC 25



### >0.25 lb a.i./A EP (82.4%) 41685102 Acceptable All dicot species tested

demonstrated no significant

effects due to clethodim

application at the maximum

application rate Vegetative Vigor

EC 25 

### >0.25 lb

a.i./A EP (82.4%) 41685103 Acceptable

MONOCOTS

Seedling Emergence

Oat

( Aveana sativa ) EC 25 

### = 0.0076 lb

a.i./A

NOAEC 2 

### = 0.0004

lb a.i./A EP (82.4%) 41685104 Acceptable 

## P lant height

Rye grass

( Lolium

perenne ) EC 25 

### = 0.0 561 lb

a.i./A

NOAEC = 0.0 31

lb a.i./A EP (82.4%) 41685104 Acceptable Plant height

Corn

( Zea mays ) EC 25 

### = 0.0 125 lb

a.i./A

NOAEC = 0.0 063

lb a.i./A EP (82.4%) 41685104 Acceptable Plant height

Onion

( Allium cepa ) EC 25 

### > 0.25 lb a.i./A

NOAEC ≥ 0.25 lb

a.i./A EP (82.4%) 41685104 Acceptable No significant effects were

observed for onions exposed

to clethodim.

## 81 TAXON ENDPOINT FORMULATION MRID STUDY

CLASS

IFICATION COMMENTS

Vegetative Vigor

Rye grass

( Lolium

perenne ) EC 25 

### = 0.003 lb

a.i./A

NOAEC 2 

### = 0.0023

lb a.i./A EP (82.4%) 4168510 5 Acceptable 

## D ry weight

Oat

( Aveana sativa ) EC 25 

### = 0.016 lb

a.i./A

NOAEC = 0.013

lb a.i./A EP (82.4%) 4168510 5 Acceptable Dry weight

Corn

( Zea mays ) EC 25 

### = 0.005 lb

a.i./A

NOAEC = 0.006

lb a.i./A EP (82.4%) 4168510 5 Acceptable Dry weight

Onion

( Allium cepa ) EC 25 

### > 0.25 lb

a.i./A

NOAEC ≥ 0.25 lb

a.i./A EP (82.4%) 4168510 5 Acceptable No significant effects were

observed for onions exposed

to clethodim.

1 

### Time

- weighted average (TWA)

2 

### EC 05 

### is used when a NOAEC could not be calculated or NOAEC is higher than the EC 25

## 82 A PPENDIX D

. Clethodim Incidents

A search for ecological incidents related to thiacloprid use, conducted on June 5, 2013, yielded two incidents involving terrestrial

plants which are summarized below.

Table X

- 1. Clethodim Incidents, as Reported in the EIIS Database

Incident ID # State, County Magnitude Year Description Legality Certainty

I002969

- 058 Florida Unknown 1995 Use of Select 2EC (a.i. Clethodim) allegedly caused damage to

cotton. Clethodim was directly treated on the field. Undetermined Possible

I022217

- 034 Illinois, Logan 100% of 75

acres 2010 On July 12, 2010 in Logan County, IL 100% of 75 acres of

soybean experienced leaf burn after the product Ignite 280 SL

(a.i. glufosinate

- ammonium) and Select (a.i. clethodim) were

applied. Alleged phytotoxic reaction to product following

application to soybean crop. The Registran t suggested the

probable cause for the leaf burn was tank contamination. Undetermined Possible



## Uncertainties Related to the Use of Incident Information from the Ecological Incident Information System

Incident data are used in risk assessments to provide evidence that the risk predictions from the screening level assessment are

supported by actual effects in the field. Incident reports submitted to EPA since approximately 1994 hav e been tracked by assignment

of incident numbers in an Incident Data System (IDS), microfiched, and then entered to a second database, the Ecological Inci dent

Information System (EIIS). Additionally, there is an on

- going effort to enter information to EII S on incident reports received prior to

establishment of current databases. Incident reports are not received in a consistent format ( e.g ., states and various labs usually have

their own formats), may involve multiple incidents involving multiple chemical s in one report, and may report on only part of a given

incident investigation ( e.g ., residues).

Incidents entered into EIIS are categorized into one of several certainty levels regarding the likelihood that a particular p esticide is

associated with the incident: highly probable, probable, possible, unlikely, or unrelated. In brief, “highly probable” incidents usually

require carcass residues and/or clear circumstances regarding the exposure. “Probable” incidents include those where residue s were

not a vailable and/or circumstances were less clear than for “highly probable.” “Possible” incidents include those where multiple

chemicals may have been involved and it is not clear what the contribution was of a given chemical. The “unlikely” category is used

, for example, where a given chemical is practically nontoxic to the category of organism killed and/or the chemical was tested for but

not detected in samples. “Unrelated” incidents are those that have been confirmed to be not pesticide

- related.

## 83 Inciden ts entered into the EIIS are also categorized as to use/misuse. Unless specifically confirmed by a state or federal agency t o be

misuse, or there was very clear misuse such as intentional baiting to kill wildlife, incidents are not typically considered m i suse.

The number of documented kills in EIIS is believed to be a small fraction of total mortality caused by pesticides. Mortality incidents

must be seen, reported, investigated, and have investigation reports submitted to EPA to have the potential for entry in to the database.

Incidents often are not seen, due to scavenger removal of carcasses, decay in the field, or simply because carcasses may be h ard to see

on many sites and/or few people are systematically looking. Poisoned animals may also move off

- site t o less conspicuous areas

before dying. Incidents may not get reported to appropriate authorities capable of investigating the incident for a variety of reasons

including the finder may not know of the importance of reporting incidents, may not know who to call, may not feel they have the

time or desire to call, or may hesitate to call because of their own involvement in the kill. Incidents reported may not get investigated

if resources are limited or may not get investigated thoroughly, with residue analy ses, for example. Also, if kills are not reported and

investigated promptly, there will be little chance of documenting the cause, since tissues and residues may deteriorate quick ly.

Reports of investigated incidents often do not get submitted to EPA, si nce reporting by states is voluntary.

Furthermore, the database relies heavily on registrant

- submitted incident reports, and registrants are currently only required to submit

detailed information on ‘major’ ecological incidents, while ‘minor’ incidents are reported aggregately.

Based on the 40 CFR (§159.184 Toxic or adverse effect incident reports), an ecological incident is considered ‘major’ if any of the

following criteria are met:

Fish or wildlife :

(A) Involves any incident caused by a pesticide currently in Formal Review for ecological concerns.

(B) Fish: Affected 1,000 or more individuals of a schooling species or 50 or more individuals of a non

- schooling species.

(C) Birds: Affected 200 or mor e individuals of a flocking species, or 50 or more individuals of a songbird species, or 5 or more

individuals of a predatory species.

(D) Mammals, reptiles, amphibians: Affected 50 or more individuals of a relatively common or herding species or 5 or mo re

individuals of a rare or solitary species.

(E) Involves effects to, or illegal pesticide treatment (misuse) of a substantial tract of habitat (greater than or equal to 10 acres,

terrestrial or aquatic).

## 84 Plants :

(A) The effect is alleged to have occu rred on more than 45 percent of the acreage exposed to the pesticide.

All other ecological incidents are considered ‘minor’ and only need to be aggregately reported. ‘Minor’ incidents reported b y the

registrants are not included in the EIIS database. Th erefore, for example, an incident could affect 900 fish, 150 birds, 45 mammals,

and 40% of an exposed crop and not be included in the EIIS database [unless is it reported by a non

- registrant ( e.g ., an incident

submitted by a state agency

– which are not sy stematically collected)]. Therefore, because the number of documented kills in EIIS is

believed to be a small fraction of total mortality caused by pesticides, absence of reports does not necessarily provide evid ence of an

absence of incidents.

## 85 APPENDIX E . STIR and SIP Inputs and Outputs

STIR



# Input

Application and Chemical Information

Enter Chemical Name clethodim

Enter Chemical Use herbicide

Is the Application a Spray? (enter y or n) y

If Spray What Type (enter ground or air) ground

Enter Chemical Molecular Weight (g/mole) 359.92

Enter Chemical Vapor Pressure (mmHg) 1.00E-07

Enter Application Rate (lb a.i./acre) 0.26

Toxicity Properties

**Bird**

Enter Lowest Bird Oral LD 50 

### (mg/kg bw) 2000

Enter Mineau Scaling Factor 1.15

Enter Tested Bird Weight (kg) 0.178

**Mammal**

Enter Lowest Rat Oral LD 50 

### (mg/kg bw) 1360

Enter Lowest Rat Inhalation LC 50 

### (mg/L) 3.9

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 

### ) 1.94E-03

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 2.43E-04

Adjusted Inhalation LD 50 

### 3.20E+01

Ratio of Vapor Dose to Adjusted Inhalation LD 50 

### 7.61E-06 Exposure not Likely Significant

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 2.75E-02

Ratio of Droplet Inhalation Dose to Adjusted Inhalation LD 50 

### 8.59E-04 Exposure not Likely Significant



## Results Mammalian (0.015 kg )

Maximum Vapor Concentration in Air at Saturation (mg/m 3 

### ) 1.94E-03

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 3.06E-04

Adjusted Inhalation LD 50 

### 2.32E+02

Ratio of Vapor Dose to Adjusted Inhalation LD 50 

### 1.32E-06 Exposure not Likely Significant

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 3.45E-02

Ratio of Droplet Inhalation Dose to Adjusted Inhalation LD 50 

### 1.49E-04 Exposure not Likely Significant **NOTE**: When entering values, press the "Enter" key

in order to update linked cells.

## 86 SIP

Table 1. Inputs

Parameter Value

Chemical name Clethodim

Solubility (in water at 25 o 

### C; mg/L) 29

Mammalian LD 50 

### (mg/kg-bw) 1360

Mammalian test species laboratory rat

Body weight (g) of "other" mammalian species

Mammalian NOAEL (mg/kg-bw) 51

Mammalian test species laboratory rat

Body weight (g) of "other" mammalian species

Avian LD 50 

### (mg/kg-bw) 2000

Avian test species northern bobwhite quail

Body weight (g) of "other" avian species

Mineau scaling factor 1.15

Mallard NOAEC (mg/kg-diet) 833

Bobwhite quail NOAEC (mg/kg-diet) 250

NOAEC (mg/kg-diet) for other bird species 0

Body weight (g) of other avian species

NOAEC (mg/kg-diet) for 2nd other bird species 0

Body weight (g) of 2nd other avian species

Table 2. Mammalian Results

Parameter Acute Chronic

Upper bound exposure (mg/kg-bw) 4.9880 4.9880

Adjusted toxicity value (mg/kg-bw) 1046.0584 39.2272

Ratio of exposure to toxicity 0.0048 0.1272

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) 23.4900 23.4900

Adjusted toxicity value (mg/kg-bw) 1440.8590 26.5746

Ratio of exposure to acute toxicity 0.0163 0.8839

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.

## 87 APPENDIX F . Summary of AgDrift Terrestrial Outputs for Clethodim

VV (Non

- Listed)

- Aerial

## 88

## 89 VV (Non

- Listed)

- Ground

## 90

## 91 SE (Non

- Listed)

- Aerial

## 92

## 93 SE (Non

- Listed)

- Ground

## 94

## 95 VV (Listed)

- Aerial

## 96

## 97 VV (Listed)

- Ground

## 98

## 99 SE (Listed)

- Aerial

## 100

## 101 SE (Listed)

- Ground

## 102

## 103 APPENDIX G

. ECOTOX Summary Tables and Accepted Papers

Clethodim 2008 Acceptable

Reference List

1. Carey III, V. F.; Smith, R. J. Jr., and Talbert, R. E. Reduced and Standard Herbicide Rates for Grass Control in

Rice (Oryza sativa). POP,GROWATER,AQUA; 1992; 6, (2): 409

- 414.

Notes: EcoReference No.: 101451

Chemical of Concern: HFP,FNP,CLT,SXD

2. De Nardo, E. A. B. and Grewal, P. S. Compatibility of Steinernema feltiae (Nematoda: Steinernematidae) with

Pesticides and Plant Growth Regulators Used in Glasshouse Plant Production.

MOR, BEHENV,AQUA; 2003; 13, (4): 441

- 448.

Notes: EcoReference No.: 71382

Chemical of Concern: SS,PCNB,MFX,FTL,FX,AZX,TPM,IPD,DFZ,CLT,ACP,ACM,PBZ

3. Ma, J. and Liang, W. Acute Toxicity of 12 Herbicides to the Green Algae Chlorella pyrenoidosa and

Scenedesmus obliquus. POPWATER,AQUA; 2001; 67, (3): 347

- 351.

Notes: EcoReference No.: 61984

Chemical of Concern: GFS,CZE,ACO,TFN,FTS,CRME,BSFM,CLT,MTL,BMN

4. Ma, J.; Lin, F.; Wang, S., and Xu, L. Acute Toxicity Assessment of 20 Herbicides to the Green Alga

Scenede smus quadricauda (Turp.) Breb. POPWATER,AQUA; 2004; 72, (6): 1164

- 1171.

Notes: EcoReference No.: 101396

Chemical of Concern:

TFN,PDM,ANL,BP,FTS,EMSF,DZP,QZF,HFP,FZFP,CLT,NSF,MTSM,TN,BSFM,CRME

5. Ma, J.; Wang, S.; Wang, P.; Ma, L.; Chen, X., and Xu, R. Toxicity Assessment of 40 Herbicides to the Green

Alga Raphidocelis subcapitata. POPWATER,AQUA; 2006; 63, (3): 456

- 462.

Notes: EcoReference No.: 83543

Chemical of Concern:

CLT,DFP,FNP,FZF,HFP,QZF,BSFM,BP,CRME,EMSF,FTS,MTSM,NSF,ACO,BTC,MTL,AMTR,A

TZ,BMN,DU ,PAQT,PMT,FXP,MCPA,QNC,PDM,TFN,GFS,GYP,SZ

6. Ma, J.; Xu, L.; Wang, S.; Zheng, R.; Jin, S.; Huang, S., and Huang, Y. Toxicity of 40 Herbicides to the Green

Alga Chlorella vulgaris. POPWATER,AQUA; 2002; 51, (2): 128

- 132.

Notes: EcoReference No.: 65938

Ch emical of Concern:

DFP,QZF,HFP,FNP,FZF,CLT,NSF,TN,EMSF,BSFM,CRME,FTS,BP,ANL,TFN,PDM,BTC,MTL,M

LT,ACO,ATZ,SZ,CZE,DU,PAQT,BMN,FXP,QNC,OXF,GYP,GFSNH

7. Perschbacher, P. W.; Stone, N.; Ludwig, G. M., and Guy, C. B. Jr. Evaluation of Effects of Common Aerially

Applied Soybean Herbicides and Propanil on the Plankton Communities of Aquaculture Ponds.

POP,PHYWATER,AQUA; 1997; 157, (1/2): 117

- 122.

Notes: EcoReference No.: 53095

Chemical of Concern: CRM,FSF,PPN,ACF,GYP,BT,IMQ,FZF,CLT

8. Schrader, K. K.; De Regt, M. Q.; Tidwell, P. D.; Tucker, C. S., and Duke, S. O. Compounds with Selective

Toxicity Towards the Off

- Flavor Metabolite

- Producing Cyanobacterium Oscillatoria cf. chalybea.

POPWATER,AQUA; 1998; 163, (1/2): 85

- 99.

Notes: EcoReference No.: 69879

Chemical of Concern:

PAQT,ACF,ATZ,DU,FMU,NFZ,IMQ,DFP,HFP,CLT,BMN,DBN,DFQ,EDT,FDE,GYP,Cu,SMU,IXB

,SXD

## 104 9. Wyss, G. S.; Charudattan, R.; Rosskopf, E. N., and Littell, R. C. Effects of Selected Pesticides and Adjuvants

on Germination and Vegetative Growth of Phomopsi s amaranthicola, a Biocontrol Agent for

Amaranthus spp. MOR,REPENV; 2004; 44, (6): 469

- 482.

Notes: EcoReference No.: 96666

Chemical of Concern:

PEB,DCF,EPTC,OXF,PAQT,CLT,TFN,NPM,PDM,AMTR,PRM,NPP,MBZ,IZT,IPD,VCZ,BMY,DM

T,MLN,CYR,LNR,DU,BS,GYPI,MTL,SXD,DCPA ,IZP,SZ,ATZ,Maneb,MZB,CuOH,CTN,FSTL



## Clethodim 2012 Refresh

- Acceptable

Reference List

1. Aigner, P. A. and Woerly, R. J. Herbicides and Mowing to Control Barb Goatgrass (Aegilops triuncialis) and

Restore Native Plants in Serpentine Grasslands. POPSOI L,ENV; 2011; 4, (4): 448

- 457.

Notes: EcoReference No.: 156883

Chemical of Concern: CLT,GYPI

2. Arregui, M. C.; Sanchez, D., and Scotta, R. Weed Control in Established Alfalfa (Medicago sativa) with

Postemergence Herbicides. PHY,POPSOIL,ENV,MIXTURE; 200 1; 15, (3): 424

- 428.

Notes: EcoReference No.: 67066

Chemical of Concern: 24DB,CLT,CRM,FTS,GYP

3. Askew, S. D.; Shaw, D. R., and Street, J. E. Graminicide Application Timing Influences Red Rice (Oryza

sativa) Control and Seedhead Reduction in Soybean (Gl ycine max). POPSOIL,ENV; 2000; 14,

176

- 181.

Notes: EcoReference No.: 59315

Chemical of Concern: CLT,FZFP,SXD

4. Askew, S. D.; Street, J. E., and Shaw, D. R. Herbicide Programs for Red Rice (Oryza sativa) Control in

Soybean (Glycine max). PHY,POP. S.D . Askew, Dept. of Plant and Soil Sciences, Mississippi State

University, Mississippi State, MS 39762////: SOIL,ENV,MIXTURE; 1998; 12, (1): 103

- 107.

Notes: EcoReference No.: 63442

Chemical of Concern: ACR,CLT,CMZ,IAZ,IZT,MTL,PDM,TFN

5. Bailly, G. C.; Dal e, R. P.; Archer, S. A.; Wright, D. J., and Kaundun, S. S. Role of Residual Herbicides for

the Management of Multiple Herbicide Resistance to ACCase and ALS Inhibitors in a Black

- Grass

Population. MOR,POPSOIL,ENV,MIXTURE; 2012; 34, (0): 96

- 103.

Notes: Ec oReference No.: 157123

Chemical of Concern: CLFP,CLT,DFC,IZPI,PDM,SMM,SS

6. Ball, D. A.; Frost, S. M., and Bennett, L. H. ACCase

- Inhibitor Herbicide Resistance in Downy Brome

(Bromus tectorum) in Oregon. GRO,MORSOIL,ENV; 2007; 55, (2): 91

- 94.

Notes: Ec oReference No.: 157092

Chemical of Concern: ALSV,CLT,FZFB,MOIL,QZFPE

7. Barnes, J. W. and Oliver, L. R. Cloransulam Antagonizes Annual Grass Control with

Aryloxyphenoxypropionate Graminicides but not Cyclohexanediones. ACC,GRO,POP. Univ

Arkansas, Dept C rop & Soil Environm Sci, Fayetteville, AR 72701 USA//: SOIL,ENV,MIXTURE;

2004; 18, (3): 763

- 772.

Notes: EcoReference No.: 156884

Chemical of Concern: CLNS,CLT,FNP,FZFP,GYP,SXD

8. Barnes, T. G. Using Herbicides to Rehabilitate Native Grasslands. POPSOIL ,ENV; 2007; 27, (1): 56

- 65.

Notes: EcoReference No.: 156982

Chemical of Concern: CLT,IAZ,SFS

## 105 9. Bedmar, F. Bermudagrass (Cynodon dactylon) Control in Sunflower (Helianthus annuus), Soybean (Glycine

max), and Potato (Solanum tuberosum) with Postemergence Graminicides. POP. Prof. F. Bedmar,

Departamento de Produccion Vegetal, Faculdad de Ciencias Agrarias

- UNMDP, C.C. 276, 7620

Balcarce, Argentina//: SOIL,ENV; 1997; 11, (4): 683

- 688.

Notes: EcoReference No.: 152009

Chemical of Concern: CLT,FNPE,FNPPE,FZFP

10.

--- . Evaluation on Postemergence Grass Herbicides Against Cynodon dactylon in Sunflower.

POPSOIL,ENV; 1992; 13, 58

- 59.

Notes: EcoReference No.: 156977

Chemical of Concern: CLT,FNPPE

11. Blackshaw, R. E.; Derksen, D. A., and Muendel, H. H. Herbicides for Weed Control in Safflower (Carthamus

tinctorius). PHY,POPSOIL,ENV,MIXTURE; 1990; 70, (1): 237

- 245.

Notes: EcoReference No.: 120455

Chemical of Concern:

ALSV,CLT,DDP,DFPM,DFQ,EFL,EMSFM,MO IL,PHMD,SXD,TFN,THF,TNM

12. Blackshaw, R. E.; Semach, G., and Entz, T. Postemergence Control of Foxtail Barley (Hordeum jubatum)

Seedlings in Spring Wheat (Triticum aestivum) and Flax (Linum usitatissimum). POP.

blackshaw@em.agr.ca//R.E. Blackshaw, Rese arch Centre, Agriculture and Agri

- Food Canada, P.O.

Box 3000, Lethbridge, Alta. T1J 4B1, Canada//: SOIL,ENV,MIXTURE; 1998; 12, (4): 610

- 616.

Notes: EcoReference No.: 63023

Chemical of Concern: CLT,FZFP,MBZ,SXD,TKY

13. Bohannan, D. R. and Jordan, T. N. E ffects of Ultra

- Low Volume Application on Herbicide Efficacy Using

Oil Diluents as Carriers. GRO,POP. Dep. Botany Plant Pathol., Purdue Univ., West Lafayette, IN

47907, USA.//: SOIL,ENV; 1995; 9, (4): 682

- 688.

Notes: EcoReference No.: 156984

Chemical of Concern: ALSV,BT,CLT,FZFP,GYP,IZT,MBZ,MTL,SOYBN,SXD

14. Bradley, K. W. and Hagood, E. S. Jr. Identification of a Johnsongrass (Sorghum halepense) Biotype Resistant

to Aryloxyphenoxypropionate and Cyclohexanedione Herbicides in Virginia. GRO,POPSOIL,ENV;

2001; 15, (4): 623

- 627.

Notes: EcoReference No.: 66802

Chemical of Concern: CLT,FZFP,SXD

15. Braverman, M. P. Control of Mannagrass (Glyceria declinata) and Southern Watergrass (Luziola fluitans) in

Water

- Seeded Rice (Oryza sativa). PHY,POPSOIL,ENV; 1 996; 10, (1): 68

- 71.

Notes: EcoReference No.: 96386

Chemical of Concern: CLT,FNP,FZF,GFS,GYP,GYPT,PAQT,SXD

16. Brighenti, A.; Voll, E., and Gazziero, D. L. P. Chloris polydactyla (L.) Sw., a Perennial Poaceae Weed:

Emergence, Seed Production, and Its M anagement in Brazil. GRO,POPSOIL,ENV; 2007; 7, (2):

84

- 88.

Notes: EcoReference No.: 156939

Chemical of Concern: ACO,ACR,CLFP,CLT,GYP,HFPM,MTC,SXD,TFN

17. Bruce, B.; Kallenbach, R. L.; Bradley, K., and Fuqua, B. Preplant Herbicides Don't Increase Forage

Production of Cereal Rye Interseeded into Bermudagrass. BCM,POPSOIL,ENV; 2009; 101, (5):

1175

- 1181.

Notes: EcoReference No.: 156888

Chemical of Concern: CLT,PQT

18. Burke, I. C.; Holland, J. B.; Burton, J. D.; York, A. C., and Wilcut, J. W. Johnsongra ss (Sorghum halepense)

## 106 Pollen Expresses ACCase Target

- Site Resistance. GRO,REPENV; 2007; 21, (2): 384

- 388.

Notes: EcoReference No.: 156994

Chemical of Concern: CLT

19. Burke, I. C.; Thomas, W. E.; Burton, J. D.; Spears, J. F., and Wilcut, J. W. A Seedl ing Assay to Screen

Aryloxyphenoxypropionic Acid and Cyclohexanedione Resistance in Johnsongrass (Sorghum

halepense). GROSOIL,ENV; 2006; 20, (4): 950

- 955.

Notes: EcoReference No.: 156992

Chemical of Concern: CLT,FZFP

20. Burke, I. C.; Wilcut, J. W., an d Cranmer, J. Cross

- Resistance of a Johnsongrass (Sorghum halepense) Biotype

to Aryloxyphenoxypropionate and Cyclohexanedione Herbicides. GROSOIL,ENV; 2006; 20, (3):

571

- 575.

Notes: EcoReference No.: 156993

Chemical of Concern: CLT,SXD

21. Campbell, M. H.; Burbidge, D. W., and Nicol, H. I. Control of Carex appressa R.Br. Using Herbicides and

Surface Sown Pasture Species. POP. NSW Agric., Agric. Res. and Vet. Centre, Forest Road,

Orange, NSW 2800, Australia.//: SOIL,ENV; 1997; 12, (3): 120

- 124.

Notes: EcoReference No.: 157039

Chemical of Concern: CLT,FZF,GYP,IZP,PMR,SXD

22. Capell, B.; Reeleder, R. D.; Grohs, R., and Zilkey, B. Evaluation of Herbicides for Management of Weeds in

Cultivation of Panax quinquefolius L. POPSOIL,ENV,MIXTURE; 1999; 23, (3) : 135

- 147.

Notes: EcoReference No.: 120528

Chemical of Concern: CLT,DMDP,DQTBr,EFL,GYP,MCPANa,OYZ

23. Cox, K. G. and Harrington, K. C. Selective Herbicide Strategies for Use in Australian Desmanthus Seed

Crops. GRO,POPSOIL,ENV,MIXTURE; 2005; 39, (3): 1 71

- 181.

Notes: EcoReference No.: 157094

Chemical of Concern:

24DB,ACF,ACFNa,ACO,ACR,ASM,ATZ,BMN,BT,CLT,CPP,CRM,CRME,CSF,CZE,DCPA,DM

DP,DQTBr,DU,EFS,EPTC,FTS,GYPI,HXZ,IMQ,IZT,LNR,MBZ,MCPA,MCPB,MTL,MTZ,NFZ,O

DZ,OXF,OYZ,PDM,PQT,PYD,PYZ,PZM,SZ,TFN,TRB

24. Cro oks, H. L.; York, A. C.; Culpepper, A. S., and Brownie, C. CGA

- 362622 Antagonizes Annual Grass

Control by Graminicides in Cotton (Gossypium hirsutum). POP. N Carolina State Univ, Dept Crop

Sci, Raleigh, NC 27695 USA Univ Georgia, Dept Crop & Soil Sci, Tif ton, GA 31793 USA N

Carolina State Univ, Dept Stat, Raleigh, NC 27695 USA//: SOIL,ENV,MIXTURE; 2003; 17, (2):

373

- 380.

Notes: EcoReference No.: 156893

Chemical of Concern: ALSV,BMN,CLT,FSF,FZFP,MOIL,MSMA,PMT,PTB,SXD

25. Czarnota, M. A. and Derr, J. Cont rolling Bamboo (Phyllostachys spp.) with Herbicides.

GRO,PHY,POPSOIL,ENV; 2007; 21, (1): 80

- 83.

Notes: EcoReference No.: 154909

Chemical of Concern: CLT,DBN,DTP,FNP,FZF,GFS,GYP,IZP,MSMA,QNC,SXD

26. Dastgheib, F.; Plew, J. N., and Hill, G. D. Chemical W eed Control in Chickpeas.

POPSOIL,ENV,MIXTURE; 1995; 0, 186

- 188.

Notes: EcoReference No.: 120308

Chemical of Concern: BT,CLT,CZE,MBZ,MCPB,TBZ

27. Dear, B. S.; Sandral, G. A., and Wilson, B. C. D. Tolerance of Perennial Pasture Grass Seedlings to Pre

- and

Post

- Emergent Grass Herbicides. GRO,PHYSOIL,ENV; 2006; 46, (5): 637

- 644.

## 107 Notes: EcoReference No.: 86670

Chemical of Concern:

ATZ,CLT,CSF,CZE,DFPM,FNPPE,FZFB,MBZ,PDM,PZM,QZFE,SXD,SZ,TFN,TKY,TRL,TSF

28. Derr, J. F. Common Reed (Phragmites australis) Response to Mowing and Herbicide Application.

GRO,POPSOIL,ENV; 2008; 1, (1): 12

- 16.

Notes: EcoReference No.: 103875

Chemical of Concern: CLT,DTP,FNP,FZF,GFS,GYPI,MSMA,QNC,SXD

29. Ferrell, J. A.; Earl, H. J., and Vencill, W. K. The Effect of Selected He rbicides on CO2 Assimilation,

Chlorophyll Fluorescence, and Stomatal Conductance in Johnsongrass (Sorghum halepense L).

CEL,PHYSOIL,ENV; 2003; 51, (1): 28

- 31.

Notes: EcoReference No.: 157102

Chemical of Concern: CLT,GYP,IAZ,NSF

30. Foy, C. L. and Witt, H. L. Annual Grass Control in Alfalfa (Medicago sativa) with Postemergence

Graminicides. POPSOIL,ENV,MIXTURE; 1992; 6, (4): 938

- 948.

Notes: EcoReference No.: 120431

Chemical of Concern: CLT,FNP,FZF,FZFP,PAQT,PQT,SXD,THF,TRB

31. Frans, R.; McClelland, M.; Jordan, D., and Johnson, B. Herbicide Trials on Field Crops, 1989.

PHY,POPSOIL,ENV,MIXTURE; 1990: 110 p.

Notes: EcoReference No.: 157119

Chemical of Concern:

24DB,ACF,ACFNa,ACR,ATZ,BFL,BMN,BT,CLT,CMZ,CRME,CZE,DMB,DMDP,DU,FMU,FNP,

FSF,IMQ,IZT,LCF,LNR,M BZ,MSMA,MTL,MTZ,NFZ,NSF,OXF,PDM,PMT,PQT,QZFE,SXD,TF

N

32. Frans, R.; McClelland, M.; Smith, C., and Jordan, D. Herbicide Trials on Field Crops, 1992.

PHY,POPSOIL,ENV,MIXTURE; 1993; 427, 63 p.

Notes: EcoReference No.: 73962

Chemical of Concern:

24BF,24D ,24DB,24DXY,ACFNa,ACR,ATZ,BMN,BT,CLT,CMZ,CRM,CZE,DMB,DU,FMU,FNP

PE,FSF,FTS,FZFP,IAZ,IMQ,IZT,LCF,LNR,MBZ,MSMA,MTL,MTZ,NFZ,NSF,OXF,PDM,PMT,P

QT,PTBNa,PYD,SXD,SYD,TFN,TPZ

33. Grichar, W. J. Comparison of Postemergence Herbicides for Common Bermudagrass (Cynod on dactylon)

Control in Peanut (Arachis hypogaea). POP. Res. Sci., Texas Agric. Exp. St., Box 755, Yoakum,

TX 77995////: SOIL,ENV,MIXTURE; 1995; 9, (4): 825

- 828.

Notes: EcoReference No.: 157103

Chemical of Concern: CLT,FNP,FNPE,FZFP,PDM,SXD

34.

--- . Co ntrol of Texas Panicum (Panicum texanum) and Southern Crabgrass (Digitaria ciliaris) in Peanuts

(Arachis hypogaea) with Postemergence Herbicides. POP. Tex. Agric. Exp. Stn., Yoakum, Tex.

77995////: SOIL,ENV; 1991; 18, (1): 6

- 8.

Notes: EcoReference No.: 1 56970

Chemical of Concern: CLT,FNP,FZFP

35. Grichar, W. J. and Boswell, T. E. Bermudagrass (Cynodon dactylon) Control with Postemergence Herbicides

in Peanut (Arachis hypogaea). POPSOIL,ENV; 1989; 3, (2): 267

- 271.

Notes: EcoReference No.: 157020

Chemic al of Concern: CLT,FNP,FZF,FZFP,MTL,SXD,TFN

36. Grichar, W. J. and Ocumpaugh, W. R. Response of Three Annual Medic Species to Postemergence

Herbicides. GRO,POPSOIL,ENV; 2009; 23, (3): 412

- 415.

## 108 Notes: EcoReference No.: 156904

Chemical of Concern: 24DB,C LT,FTS,IZT,IZX

37. Griffin, J. L.; Miller, D. K., and Salassi, M. E. Johnsongrass (Sorghum halepense) Control and Economics of

Using Glyphosate

- Resistant Soybean in Fallowed Sugarcane Fields. POPSOIL,ENV; 2006; 20, (4):

980

- 985.

Notes: EcoReference No.: 155807

Chemical of Concern: CLT,FZF,GYP

38. Han, J.; Liu, H.; Guo, P., and Hao, C. Weed Control in Summer

- Sown Soybeans with Flumioxazin plus

Acetochlor and Flumiclorac

- Pentyl plus Clethodim. POP. College of Agronomy, Shanxi

Agricultural University

, Taigu, eo . Re . China////: SOIL,ENV,MIXTURE; 2002; 2, (2): 120

- 122.

Notes: EcoReference No.: 157118

Chemical of Concern: ACO,CLT,FMCP,FMX

39. Harker, K. N. Ammonium Sulfate Effects on the Activity of Herbicides for Selective Grass Control.

GRO,POP. Res. Sci., Agric. Canada Res. Stn., Bag Serv. 5000, Lacombe, AB T0C 1S0, Canada////:

SOIL,ENV,MIXTURE; 1995; 9, (2): 260

- 266.

Notes: EcoReference No.: 157105

Chemical of Concern: CLT,FNP,FZF,NHSO4

40. Harrington, K. C. and Rahman, A. Tolerance to Herbic ides of Ground Cover Species for New Zealand

Orchards. PHYSOIL,ENV,MIXTURE; 1998; 13, (3): 111

- 115.

Notes: EcoReference No.: 70295

Chemical of Concern:

AMTL,ASM,CLT,CPR,CSF,DBN,DMB,DMDP,DQTBr,DU,EFS,FZF,GFS,GYP,LNR,MCPA,MC

PP2,NFZ,ODZ,OXF,OYZ,PAQT,PDM,PQT ,SXD,SZ,TBNU,TPR

41. Harrington, K. C.; Southward, R. C.; Kitchen, K. L., and He, X. Z. Investigation of Herbicides Tolerated by

Stevia rebaudiana Crops. GRO,PHY,POP. [Harrington, KC//: SOIL,ENV; 2011; 39, (1): 21

- 33.

Notes: EcoReference No.: 157121

Ch emical of Concern:

ASM,BT,CLT,EFS,FTS,FXPM,LNR,MBZ,OYZ,PDM,PMT,PYZ,TFN,THFM,TRB

42. Hennigh, D. S.; Al

- Khatib, K.; Stahlman, P. W., and Shoup, D. E. Prairie Cupgrass (Eriochloa contract) and

Windmillgrass (Chloris verticillata) Response to Glyphosate and Acetyl

- CoA Carboxylase

Inhibiting Herbicides. ACC,GRO,REPSOIL,ENV,MIXTURE; 2005; 53, (3): 315

- 322.

Notes: EcoReference No.: 157106

Chemical of Concern: ACO,ACR,ATZ,CLT,DMM,FFC,GYPI,IXF,MTC,PDM,RIM,SXD

43. Hochberg, O.; Sibony, M., and Rubin, B. The Re sponse of ACCase

- Resistant Phalaris paradoxa Populations

Involves Two Different Target Site Mutations. GRO,POPSOIL,ENV,MIXTURE; 2009; 49, (1): 37

-

46.

Notes: EcoReference No.: 156947

Chemical of Concern: CLFP,CLT,DFPM,FFC,PNX,PZM,QZFPE,TKY

44. Ivany, J. A. and Sanderson, J. B. Quackgrass (Elytrigia repens) Control in Potatoes (Solanum tuberosum)

with Clethodim. GRO,POP. IvanyJ@agr.gc.ca//: SOIL,ENV,MIXTURE; 2003; 84, (1): 27

- 35.

Notes: EcoReference No.: 82407

Chemical of Concern: ALSV,CLT,MBZ,NHSO4,SXD

45. Johnson III, W. C.; Prostko, E. P., and Grey, T. L. Annoying Trends in Strip

- Tillage Weed Control in Peanut:

What are Our Options? POP. BOOK

http://www.ag.auburn.edu/auxiliary/nsdl/scasc/Proceedings/2002/JohnsonWC.pdf//: SOIL,ENV;

2002: 165

- 170.

## 109 Notes: EcoReference No.: 156906

Chemical of Concern: ACR,CLT,DMM,EFL,MTL,PDM,SXD

46. Johnson III, W. C.; Prostko, E. P., and Mullinix, B. G. Jr. Texas Panicum (Panicum texanum) Control in

Strip

- Tillage Peanut (Arachis hypogaea) Production. PHY,POPSOIL,E NV,MIXTURE; 2002; 29,

(2): 141

- 145.

Notes: EcoReference No.: 120386

Chemical of Concern: ACR,CLT,DMM,EFL,MTL,PDM,SXD

47. Kurtz, M. E. and Neill, S. W. Tolerance of Kenaf to Selected Postemergence Herbicides. GRO,PHY. Delta

Branch, Mississippi Agric. Fo r. Ex . Stn., Stoneville, MS//: SOIL,ENV; 1992; 6, (1): 125

- 128.

Notes: EcoReference No.: 157110

Chemical of Concern: ACF,BT,CLT,CRM,FSF,FZFP,IAZ,IMQ,IZT,LCF,MSMA,MTS,SMU,SXD

48. Leys, A. R.; Plater, B., and Cullis, B. Response of Six Temperate Annual Grass Weeds to Six Selective

Herbicides. POPSOIL,ENV; 1988; 3, (4): 163

- 168.

Notes: EcoReference No.: 157040

Chemical of Concern: CLT,FNPE,FZFP,QZFE,SXD

49. Marshall, G.; Kirkwood , R. C., and Leach, G. E. Comparative Studies on Graminicide

- Resistant and

Susceptible Biotypes of Eleusine indica. POP,REP. Dep. Plant Sci., Scottish Agric. Coll.,

Auchincruive, Ayr KA6 5HW, UK.////: SOIL,ENV; 1994; 34, (3): 177

- 185.

Notes: EcoReference No.: 156975

Chemical of Concern: CLT,DFP,FNP,FZF,SXD,TKY

50. Matthews, N.; Powles, S. B., and Preston, C. Mechanisms of Resistance to Acetyl

- Coenzyme A Carboxylase

Inhibiting Herbicides in a Hordeum leporinum Population. ACC,BCM,MORSOIL,ENV; 2000; 56,

441

- 447.

Notes: EcoReference No.: 63953

Chemical of Concern: CLT,DFP,FZFB,QZFPE,SXD,TKY

51. McCullough, P. E.; Hart, S. E.; Askew, S.; Dernoeden, P. H.; Reicher, Z., and Weisenberger, D. Kentucky

Bluegrass Control with Postemergence Herbicides. POPSOI L,ENV; 2006; 41, (1): 255

- 258.

Notes: EcoReference No.: 87931

Chemical of Concern: CLT,GFSNH,GYPI,RIM,SXD

52. McWhorter, C. G.; Barrentine, W. L., and Hanks, J. E. Postemergence Grass Control with Herbicides Applied

at ULV in Paraffinic Oil. POP. Plant Physiol., Applic. Tech. Res. Unit, Agric Res. Serv., U.S. Dep.

Agric., Stoneville, Miss. 38776.//: SOIL,ENV; 1992; 6, (2): 262

- 268.

Notes: EcoReference No.: 157069

Chemical of Concern: ALSV,CLT,COTSD,FZFP,KER,MOIL,SOYBN,SXD

53. Minton, B. W.; Kurtz, M. E., and Shaw, D. R. Barnyardgrass (Echinochloa crus

- galli) Control with Grass and

Broadleaf Weed Herbicide Combinations. POP. Dep. Plant Pathol. Weed Sci., Mississippi State

Univ., Mississippi State, MS //: SOIL,ENV,MIXTURE; 1989; 37, (2): 223

- 227.

Not es: EcoReference No.: 157113

Chemical of Concern: 24DB,ACF,ALSV,BT,CLT,CRM,FNP,FSF,FZFP,IMQ,LCF,MOIL,SXD

54. Moyer, J. R. and Schaalje, G. B. Quackgrass (Elytrigia repens) Interference and Control in Seed Alfalfa

(Medicago sativa). POP. Agric. Can. Res. Stn., Lethbridge, AB, Can. T1J 4B1.//:

SOIL,ENV,MIXTURE; 1993; 7, (1): 58

- 64.

Notes: EcoReference No.: 157070

Chemical of Concern: CLT,FZFP,NHSO4,SXD

55. Nastasi, P. and Smith, R. J. Jr. Red Rice (Oryza sativa) Control in Soybeans (Glycine max).

## 110 POPSO IL,ENV,MIXTURE; 1989; 3, (2): 389

- 392.

Notes: EcoReference No.: 73747

Chemical of Concern: ACR,CLT,FZFP,FZP,IMQ,IZT,MTL,PDM

56. Ndou, A. Interaction of Weed Emergence, Weed Density, and Herbicide Rate in Soybean.

MOR,POPSOIL,ENV,MIXTURE; 2009: 102 p. ( UMI# 3380407).

Notes: EcoReference No.: 152884

Chemical of Concern: CLT,GYP,LCF,MBZ,MTC,SFZ

57. Nelson, K. A. and Renner, K. A. Postemergence Weed Control with CGA

- 277476 and Cloransulam

- Methyl

in Soybean (Glycine max). GRO,PHY,POP. Prof. K.A. Renner, Department of Crop and Soil

Sciences, Michigan State University, East Lansing, MI 48824

- 1325, United States//:

SOIL,ENV,MIXTURE; 1998; 12, (2): 293

- 299.

Notes: EcoReference No.: 64012

Chemical of Concern: ACF,CLNSM,CLT,CRM,THF

58. Novo, R. J.; Darre, C. A., and Zumelzu, G. Weed Control in Aloysia polystachya with Pre and Post

Emergence Herbicides. PHY,POPSOIL,ENV; 1998; 20, (3): 679

- 682.

Notes: EcoReference No.: 70779

Chemical of Concern: BMN,BT,CLT,FSF,FZFB,IZT,PAQT,PDM,PMT,PQT,SZ,TFN,TRB

59. Palmer , E. W.; Shaw, D. R., and Holloway, J. C. Jr. Influence of CGA

- 277476 on Efficacy of Postemergence

Graminicides. POPSOIL,ENV,MIXTURE; 1999; 13, (1): 48

- 53.

Notes: EcoReference No.: 157073

Chemical of Concern: CLT,FZFP

60. Park, K. W. and Mallory

- Smith, C. A. Multiple Herbicide Resistance in Downy Brome (Bromus tectorum)

and Its Impact on Fitness. GRO,PHYSOIL,ENV; 2005; 53, (6): 780

- 786.

Notes: EcoReference No.: 154031

Chemical of Concern: ATZ,CLT,CMZ,DU,EFS,FZF,GFS,GYP,MBZ,NFZ,PAQT,TFN,TRB

61. Persc hbacher, P. W.; Stone, N.; Ludwig, G. M., and Guy, C. B. Jr. Evaluation of Effects of Common

Aerially

- Applied Soybean Herbicides and Propanil on the Plankton Communities of Aquaculture

Ponds. POPAQUA; 1997; 157, (1

- 2): 117

- 122.

Notes: EcoReference No.: 5 3095

Chemical of Concern: ACF,ACFNa,BT,CLT,CRM,CRME,FSF,FZF,FZFB,GYP,GYPI,IMQ,PPN

62. Petersen, J.; Neser, J. M., and Dresbach

- Runkel, M. Resistant Factors of Target

- Site and Metabolic Resistant

Black

- Grass (Alopecurus myosuroides Huds.) Biotypes Against Different ACC

- ase

- Inhibitors.

GRO. pryrtdrn@fh

- bingen.de//: SOIL,ENV; 2008; Sp. Iss. 21, 23

- 28.

Notes: EcoReference No.: 156760

Chemical of Concern: CLT

63. Prokop, M. and Veverka, K. Influence of Droplet Spectra on the Efficiency of Contact and Systemic

Herbicides. POP. State Phytosanitary Admin, Div Plant Protect Equip, Brno, Czech Republic

Mendel Univ Agr & Forestry Brno, Brno, Czech Republic//: SOIL,ENV,M IXTURE; 2003; 49, (2):

75

- 80.

Notes: EcoReference No.: 156921

Chemical of Concern: BT,CLT

64. Prostko, E. P.; Johnson III, W. C., and Mullinix, B. G. Jr. Annual Grass Control with Preplant Incorporated

and Preemergence Applications of Ethalfluralin and Pendimethalin in Peanut (Arachis hypogaea).

PHY,POPSOIL,ENV,MIXTURE; 2001; 15, (1): 36

- 41.

Notes: EcoReference No.: 67060

Chemical of Concern: 24DB,BT,CLT,EFL,PDM,PYD,SXD

## 111 65. Reynolds, J. H.; Krueger, W. A., and Walker, C. L. Effects of Clethodim on Se edhead Density, Forage Yield,

and Quality of Tall Fescue (Festuca arundinacea). BCM,POP,REP. Plant and Soil Sci. Dep., Univ.

Tennessee, Knoxville, TN 37901

- 1071, USA.//: SOIL,ENV; 1993; 7, (3): 751

- 755.

Notes: EcoReference No.: 157075

Chemical of Concern : ALSV,CLT,MOIL

66. Rosales

- Robles, E.; Chandler, J. M.; Senseman, S. A., and Prostko, E. P. Integrated Johnsongrass

Management in Cotton with Reduced Rates of Clethodim and Cultivation. POPSOIL,ENV; 1999; 3,

27

- 34.

Notes: EcoReference No.: 63480

Chem ical of Concern: CLT

67. Ruffner, M. E. and Barnes, T. G. Natural Grassland Response to Herbicides and Application Timing for

Selective Control of Tall Fescue, an Invasive Cool

- Season Grass. POPSOIL,ENV; 2010; 3, (3):

219

- 228.

Notes: EcoReference No.: 156927

Chemical of Concern: ALSV,CLT,MOIL

68. Schuh, J. F. and Harvey, R. G. Woolly Cupgrass (Eriochloa villosa (Thunb.) Kunth) Control in Corn (Zea

mays L.) and Soybean (Glycine max (L.) Merr.) and the Influence of Moisture on Imazethapyr

Diffusion. PH Y,POPSOIL,ENV,MIXTURE; 1990: 334 p. (UMI#9100162).

Notes: EcoReference No.: 116575

Chemical of Concern:

24D,24DXY,ACF,ACO,ACR,AMTR,ATZ,BT,BTY,CLT,CMZ,CYC,CZE,DFPM,EPTC,FNP,FZFP

,GYP,IZT,LNR,MBZ,MTL,NSF,PAQT,PDM,SXD,SZ,TFN

69. Smeda, R. J.; Snipes, C. E., and Barrentine, W. L. Identification of Graminicide

- Resistant Johnsongrass

(Sorghum halepense). PHY,POPSOIL,ENV; 1997; 45, (1): 132

- 137.

Notes: EcoReference No.: 155808

Chemical of Concern: CLT,FNPE,FZFP,GFS,GYP,GYPT,IZT,LNR,MSMA,NSF,PAQT,PQT,SXD

70. Snipes, C. E. and Allen, R. L. Interaction of Graminicides Applied in Combination with Pyrithiobac. POP.

Mississippi Agric. For. Exp. Stn., Delta Branch, Stoneville, MS 38776, USA.//:

SOIL,ENV,MIXTURE; 1996; 10, (4): 889

- 892.

Notes: EcoReference No.: 157 076

Chemical of Concern: CLT,FZFP,NFZ,PTB,SXD

71. Stanton, R. A.; Pratley, J. E.; Hudson, D., and Dill, G. M. Herbicide Tolerant Canola Systems and Their

Impact on Winter Crop Rotations. POPSOIL,ENV,MIXTURE; 2010; 117, (1): 161

- 166.

Notes: EcoReference No.: 150459

Chemical of Concern: ATZ,CLT,CSF,DFPM,DQT,GYP,PQT,SZ,TFN,TSF

72. Stoltenberg, D. E. and Wiederholt, R. J. Giant Foxtail (Setaria faberi) Resistance to

Aryloxyphenoxypropionate and Cyclohexanedione Herbicides. GRO,MOR,POP. Dep. Agron.,

Univ. Wisconsin, Madison, WI 53706, USA.//: SOIL,ENV; 1995; 43, (4): 527

- 535.

Notes: EcoReference No.: 157078

Chemical of Concern: CLT,DFPM,FNPE,IZT,LNR,NSF,OXF,SXD

73. Talbert, R. E.; Wichert, R. A.; Carey III, V. F.; Johnson, D. H.; Ruff, D. F., and Kendig , J. A. Field

Evaluation of Herbicides on Small Fruit, Vegetable and Ornamental Crops 1991.

PHY,POPSOIL,ENV,MIXTURE; 1992; 417, 58 p.

Notes: EcoReference No.: 70759

Chemical of Concern:

ACFNa,ATZ,BS,BT,CLT,CMZ,CRM,DCPA,DTP,DU,EFL,EPTC,FSF,FZFP,GFSNH,GYP I,IMQ,I

XB,IZT,MBZ,MTL,NPM,NPP,OXF,OYZ,PDM,PQT,PYD,SXD,SZ,TFN,TPZ,TRB

## 112 74. Talbert, R. E.; Wichert, R. A.; McCarty, J. T.; Johnson, D. H.; Ruff, D. F.; Kendig, J. A., and Carey, V. F.

Field Evaluation of Herbicides on Small Fruit, Vegetable and Ornamental Crops 1990.

PHY,POPSOIL,ENV,MIXTURE; 1991; 412, 56 p.

Notes: EcoReference No.: 155813

Chemical of Concern:

ACF,ACFNa,ACR,ATZ,BS,BT,CLT,CMZ,CPR,CRME,CYC,DCPA,DEE,DTP,DU,EFL,EPTC,FSF

,GFSNH,GYPI,IAZ,IMQ,IXB,IZT,LCF,MB,MTL,MTZ,NPM,NPP,NSF,OXF,OYZ,PDM,PHMD,P

QT,PRM,SXD,TFN,TRB

75. Taverner, J.; Beasley, J. S.; Strahan, R. E.; Griffin, J. L., and Borst, S. M. Selective Postemergence Herbicide

Control of Torpedograss in Centipedegrass. PHY,POPSOIL,ENV; 2011; 25, (2): 212

- 216.

Notes: EcoReference No.: 154969

Chemical of Concern: CLT,QNC,SXD

76. Teuton, T. C. Management of Hybrid Bluegrass (Poa arachnifera Torr. x Poa pratensis L.) in the Transition

Zone. BCM,GRO,PHY,POPSOIL,ENV; 2006: 159 p. (UMI#3214429).

Notes: EcoReference No.: 154952

Chemical of Concer n:

BP,CLT,CSF,DFPM,DTP,EPH,HSF,IAZ,IMQ,MTSM,ODZ,OYZ,PBZ,PCZ,PDM,PRM,QNC,RIM,

SFS,SXD,TFN,TXE

77. Tredaway, J. A.; Patterson, M. G., and Wehtje, G. R. Interaction of Clethodim with Pyrithiobac and

Bromoxynil Applied in Low Volume. POP. Dep. Plant Soil Sci ., Univ. Tenn., Knoxville, TN

37901

- 1071, USA.//: SOIL,ENV,MIXTURE; 1998; 12, (1): 185

- 189.

Notes: EcoReference No.: 157082

Chemical of Concern: BMN,CLT,PTB

78. Wall, D. A. and Smith, M. A. H. Quackgrass (Elytrigia repens) Management in Flax (Linum usit atissimum).

POP. Agr & Agri Food Canada, Brandon Res Ctr, Brandon, MB R7A 5Y3, Canada Agr & Agri

Food Canada, Cereal Res Ctr, Winnipeg, MB R3T 2M9, Canada//: SOIL,ENV,MIXTURE; 2000;

80, (2): 411

- 417.

Notes: EcoReference No.: 156933

Chemical of Concern: B MN,CLT,DFPM,FZFP,GYP,SXD

79. Webber III, C. L. Kenaf (Hibiscus cannabinus L.) Response to Four Grass Control Herbicides Broadcast

Postemergence. GRO,POPSOIL,ENV; 1994; 8, (3): 457

- 460.

Notes: EcoReference No.: 156934

Chemical of Concern: CLT,FZF,SXD

8 0. Webster, T. M.; Bednarz, C. W., and Hanna, W. W. Sensitivity of Triploid Hybrid Bermudagrass Cultivars

and Common Bermudagrass to Postemergence Herbicides. GRO,POP. USDA ARS, Coastal Plain

Expt Stn, Crop Protect & Management Res Unit, Tifton, GA 31794 USA Univ Georgia, Dept Crop

& Soil Sci, Coastal Plain Expt Stn, Tifton, GA 31794 USA//: SOIL,ENV,MIXTURE; 2003; 17, (3):

509

- 515.

Notes: EcoReference No.: 156935

Chemical of Concern: CLT,FZFP,GFS,GYP

81. Webster, T. M.; Hanna, W. W., and Mullinix, B. G . Jr. Bermudagrass (Cynodon spp.) Dose

- Response

Relationships with Clethodim, Glufosinate and Glyphosate. GRO,PHYSOIL,ENV; 2004; 60, (12):

1237

- 1244.

Notes: EcoReference No.: 155802

Chemical of Concern: CLT,GFS,GYP

82. Wiederholt, R. J. and Stoltenberg , D. E. Cross

- Resistance of a Large Crabgrass (Digitaria sanguinalis)

Accession to Aryloxyphenoxypropionate and Cyclohexanedione Herbicides. GROSOIL,ENV;

1995; 9, (3): 518

- 524.

## 113 Notes: EcoReference No.: 156936

Chemical of Concern: ALSV,CLT,DFP,FNP,FZFP,IZ T,LNR,MOIL,SXD

83. Wilcut, J. W. Efficacy and Economics of Common Bermudagrass (Cynodon dactylon) Control in Peanut

(Arachis hypogaea). POP. Dep. Agron., Box 748, Coastal Plain Exp. Stn., Univ. Ga., Tifton, Ga.

31793

- 0748.//: SOIL,ENV,MIXTURE; 1991; 18, (2): 106

- 109.

Notes: EcoReference No.: 156971

Chemical of Concern: CLT,FZFP,SXD

84. Wright, S. D.; Vargas, R. N.; Martin

- Duvall, T., and Jimenez, M. R. Jr. Pyrithiobac, Grass Herbicide

Antagonism Study in Cotton. POPSOIL,ENV,MIXTURE; 1998; 51, 17

- 18.

Notes: EcoReference No.: 156937

Chemical of Concern: CLT,FZF,PTB,SXD

85. Yu, Q.; Collavo, A.; Zheng, M. Q.; Owen, M.; Sattin, M., and Powles, S. B. Diversity of Acetyl

- Coenzyme A

Carboxylase Mutations in Resistant Lolium Populations: Evaluation Using Clethodim.

MORSOIL,ENV; 2007; 145, (2): 547

- 558.

Notes: EcoReference No.: 111509

Chemical of Concern: CLT,DFP,FZF,PNX,SXD,TKY

## 114 APPENDIX H. ECOTOX Open Literature That Passed Initial Screen

Accepted ECOTOX DATA Table

– Clethodim

The code list for ECOTOX can be found at: http://cfpub.epa.gov/ecotox/blackbox/help/codelist.pdf

May 2008

Chemical

Name Genus Species Common

Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc

Units

Preferred %

Purity Ref #

Clethodim Chlorella vulgaris Green Algae POP POP PGRT EC50 4 d 4.644564 mg/L 12 65938

Clethodim Chlorella pyrenoidosa Green Algae POP POP PGRT EC50 4 d 10.842084 mg/L 12 61984

Clethodim Scenedesmus acutus var.

acutus Green Algae POP POP PGRT EC50 4 d 6.816684 mg/L 12 61984

Clethodim Scenedesmus quadricauda Green Algae POP POP PGRT EC50 4 d 9.228 mg/L 12 101396

Clethodim Oscillatoria chalybea Blue

- Green

Algae POP POP ABND LOEC 5 d 1000 uM 99 69879

Clethodim Pseudokirchneriella subcapitata Green Algae POP POP ABND LOEC 5 d 1000 uM 99 69879

Clethodim Pseudokirchneriella subcapitata Green Algae POP POP ABND EC100 5 d 1000 uM 99 69879

Clethodim Oscillatoria chalybea Blue

- Green

Algae POP POP ABND EC100 5 d 1000 uM 99 69879

Clethodim Plankton sp. Plankton POP POP PSYN NOAEL 2 d 0.07 AI kg/ha 100 53095

Clethodim Echinochloa crus

- galli Barnyard

Grass POP POP ABND LOAEL ea 0.03 kg/ha 100 101451

Clethodim Echinochloa crus

- galli Barnyard

Grass POP POP ABND LOAEL ea 0.03 kg/ha 100 101451

Clethodim Leptochloa fusca Malabar

Sprangletop POP POP ABND LOAEL ea 0.03 kg/ha 100 101451

Clethodim Leptochloa fusca Malabar

Sprangletop POP POP ABND LOAEL ea 0.03 kg/ha 100 101451

Clethodim Oryza sativa Rice PHY INJ DAMG LOAEL 14 d 0.03 kg/ha 100 101451

Clethodim Oryza sativa Rice PHY INJ DAMG NOAEL 14 d 0.06 kg/ha 100 101451

Clethodim Oryza sativa Rice POP POP BMAS NOAEL hv 0.06 kg/ha 100 101451

Clethodim Echinochloa crus

- galli Barnyard

Grass POP POP ABND LOAEL ea 0.03 kg/ha 100 101451

Clethodim Echinochloa crus

- galli Barnyard

Grass POP POP ABND LOAEL ea 0.03 kg/ha 100 101451

Clethodim Leptochloa fusca Malabar

Sprangletop POP POP ABND LOAEL ea 0.03 kg/ha 100 101451

Clethodim Leptochloa fusca Malabar

Sprangletop POP POP ABND LOAEL ea 0.03 kg/ha 100 101451

## 115 Chemical

Name Genus Species Common

Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc

Units

Preferred %

Purity Ref #

Clethodim Oryza sativa Rice PHY INJ DAMG LOAEL 21 d 0.03 kg/ha 100 101451

Clethodim Oryza sativa Rice PHY INJ DAMG LOAEL 21 d 0.03 kg/ha 100 101451

Clethodim Oryza sativa Rice POP POP BMAS NOAEL hv 0.03 kg/ha 100 101451

Clethodim Pseudokirchneriella subcapitata Green Algae POP POP ABND EC50 4 d 2.744112 mg/L 12 83543

Clethodim Steinernema feltiae Nematode BEH BEH GBHV NOAEL 9 d 1.26 ml/L 12.6 71382

Clethodim Steinernema feltiae Nematode MOR MOR SURV NOAEL 3 d 1.26 ml/L 12.6 71382

Clethodim Phomopsis amaranthicola Fungus MOR MOR MORT LD50 1.0125 d 0.48 L/ha 100 96666

Clethodim Phomopsis amaranthicola Fungus MOR MOR MORT LD50 1.0125 d 0.48 L/ha 100 96666



## July 2012

- Refresh

Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Setaria faberi Mutton

Bluegrass GRO GRO BMAS ED50 21 d 8.90E

- 05 lb/acre 100 157078

Clethodim Setaria faberi Mutton

Bluegrass GRO GRO BMAS ED50 21 d 0.000712 lb/acre 100 157078

Clethodim Digitaria sanguinalis Purple Crabgrass GRO GRO BMAS ED50 21 d 0.00178 lb/acre 100 156936

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC50 28 d 0.00224784 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC50 28 d 0.00224784 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC50 28 d 0.00224784 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC50 28 d 0.0024976 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC50 28 d 0.00274736 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC80 28 d 0.00349664 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC50 28 d 0.00349664 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC80 28 d 0.00349664 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC80 28 d 0.0037464 lb/acre 100 152884

Clethodim Sorghum arundinaceum Shattercane POP POP DBMS EC50 28 d 0.0037464 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC80 28 d 0.0037464 lb/acre 100 152884

Clethodim Lolium rigidum Wimmera

Ryegrass MOR MOR MORT LD50 21 d 0.003916 lb/acre 100 111509

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.00449568 lb/acre 100 152884

Clethodim Sorghum arundinaceum Shattercane POP POP DBMS EC50 28 d 0.00449568 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC50 28 d 0.00449568 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC80 28 d 0.00449568 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC50 28 d 0.00474544 lb/acre 100 152884

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS NOAEL LOAEL 57 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM PRCO NOAEL LOAEL 57 d 0.004984 lb/acre 100 157075

## 116 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS LOAEL 26 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED LOAEL 26 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM FIBR LOAEL 26 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS NOAEL LOAEL 194 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED NOAEL LOAEL 194 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS LOAEL 58 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED LOAEL 58 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM PRCO LOAEL 58 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED NOAEL LOAEL 187 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS LOAEL 58 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED LOAEL 58 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS NOAEL LOAEL 56 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED NOAEL LOAEL 56 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS NOAEL LOAEL 34 d 0.004984 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED NOAEL LOAEL 34 d 0.004984 lb/acre 100 157075

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.0049952 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC50 28 d 0.0049952 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC80 28 d 0.00549472 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.00574448 lb/acre 100 152884

Clethodim Setaria faberi Mutton

Bluegrass GRO GRO BMAS ED50 21 d 0.00623 lb/acre 100 157078

Clethodim Phalaris paradoxa Hood

Canarygrass GRO GRO WGHT ED50 21 d 0.006408 lb/acre 100 156947

Clethodim Sorghum arundinaceum Shattercane POP POP DBMS EC50 28 d 0.00649376 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.00674352 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC80 28 d 0.00699328 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC80 28 d 0.00724304 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC80 28 d 0.00774256 lb/acre 100 152884

Clethodim Sorghum bicolor Broomcorn POP POP DBMS EC80 28 d 0.00799232 lb/acre 100 152884

Clethodim Sorghum arundinaceum Shattercane POP POP DBMS EC50 28 d 0.00824208 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC80 28 d 0.00824208 lb/acre 100 152884

Clethodim Alopecurus myosuroides Blackgrass MOR MOR MORT LD50 21 d 0.0084194 lb/acre 100 157123

Clethodim Sorghum arundinaceum Shattercane POP POP DBMS EC50 28 d 0.00849184 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.0087416 lb/acre 100 152884

Clethodim Sorghum halepense Johnson Grass GRO GRO WGHT EC50 21 d 0.0089 lb/acre 100 156993

Clethodim Sorghum arundinaceum Shattercane POP POP DBMS EC50 28 d 0.00899136 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC80 28 d 0.00924112 lb/acre 100 152884

Clethodim Sorghum arundinaceum Shattercane POP POP DBMS EC50 28 d 0.00924112 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.00949088 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.00974064 lb/acre 100 152884

## 117 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.00974064 lb/acre 100 152884

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS NOAEL LOAEL 188 d 0.009968 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED NOAEL LOAEL 188 d 0.009968 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS NOAEL LOAEL 188 d 0.009968 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED NOAEL LOAEL 57 d 0.009968 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM PRCO NOAEL LOAEL 57 d 0.009968 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM FIBR NOAEL LOAEL 26 d 0.009968 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM FIBR NOAEL LOAEL 194 d 0.009968 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS NOAEL LOAEL 187 d 0.009968 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM PRCO NOAEL LOAEL 58 d 0.009968 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS NOAEL LOAEL 187 d 0.009968 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM PRCO NOAEL LOAEL 56 d 0.009968 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM PRCO NOAEL LOAEL 34 d 0.009968 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED NOAEL LOAEL 34 d 0.009968 lb/acre 100 157075

Clethodim Alopecurus myosuroides Blackgrass GRO GRO WGHT ED50 20 d 0.01 L/ha 100 156760

Clethodim Alopecurus myosuroides Blackgrass GRO GRO WGHT ED50 20 d 0.01 L/ha 100 156760

Clethodim Alopecurus myosuroides Blackgrass GRO GRO WGHT ED50 20 d 0.01 L/ha 100 156760

Clethodim Digitaria sanguinalis Purple Crabgrass GRO GRO BMAS ED50 21 d 0.01068 lb/acre 100 156936

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.01073968 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC80 28 d 0.01073968 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.0112392 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.01148896 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.01148896 lb/acre 100 152884

Clethodim Sorghum arundinaceum Shattercane POP POP DBMS EC50 28 d 0.01173872 lb/acre 100 152884

Clethodim Sorghum arundinaceum Shattercane POP POP DBMS EC50 28 d 0.01273776 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC80 28 d 0.01398656 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.01648416 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.01673392 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.0174832 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.01773296 lb/acre 100 152884

Clethodim Setaria faberi Mutton

Bluegrass GRO GRO BMAS ED50 21 d 0.018067 lb/acre 100 157078

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.01948128 lb/acre 100 152884

Clethodim Lolium rigidum Wimmera

Ryegrass POP POP BMAS ED50 42 d 0.019758 lb/acre 100 157040

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM PRCO NOAEL 188 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED NOAEL 188 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM PRCO NOAEL 188 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS NOAEL 57 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED NOAEL 57 d 0.019936 lb/acre 100 157075

## 118 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS NOAEL 26 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED NOAEL 26 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED NOAEL 194 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM FIBR NOAEL 194 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS NOAEL 194 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM PRCO NOAEL 187 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED NOAEL 187 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM PRCO NOAEL 187 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS NOAEL 56 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue REP REP SEED NOAEL 56 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM PRCO NOAEL 56 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue POP POP BMAS NOAEL 34 d 0.019936 lb/acre 100 157075

Clethodim Schedonorus arundinaceus Tall Fescue BCM BCM PRCO NOAEL 34 d 0.019936 lb/acre 100 157075

Clethodim Hordeum murinum ssp.

leporinum Leporinum

Barley MOR MOR MORT LD50 35 d 0.02047 lb/acre 100 63953

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC50 28 d 0.02097984 lb/acre 100 152884

Clethodim Hordeum vulgare Barley GRO GRO WGHT LOAEL 28 d 0.02225 lb/acre 100 157105

Clethodim Hordeum vulgare Barley GRO GRO WGHT LOAEL 28 d 0.02225 lb/acre 100 157105

Clethodim NR Poaceae Grass Family POP POP CNTL LOAEL 14 d 0.02314 lb/acre 100 156984

Clethodim NR Poaceae Grass Family POP POP CNTL LOAEL 14 d 0.02314 lb/acre 100 156984

Clethodim NR Poaceae Grass Family POP POP CNTL LOAEL 14 d 0.02314 lb/acre 100 156984

Clethodim Sorghum halepense Johnson Grass GRO MPH LGTH ED50 5 d 0.0248 ppm 100 156992

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 70 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 70 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 70 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

## 119 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 70 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 70 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 70 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 21 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 70 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 70 d 0.02492 lb/acre 100 157069

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 70 d 0.02492 lb/acre 100 157069

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP CNTL LOAEL 9 d 0.024976 lb/acre 100 157082

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC80 28 d 0.02647456 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC80 28 d 0.02847264 lb/acre 100 152884

Clethodim Bromus tectorum Downy Brome GRO GRO WGHT ED50 21 d 0.02848 lb/acre 100 154031

## 120 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Alopecurus myosuroides Blackgrass MOR MOR MORT LD50 21 d 0.02937 lb/acre 100 157123

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC80 28 d 0.03122 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP DBMS EC80 28 d 0.03346784 lb/acre 100 152884

Clethodim Phalaris paradoxa Hood

Canarygrass POP POP BMAS ED50 42 d 0.034532 lb/acre 100 157040

Clethodim Sorghum halepense Johnson Grass GRO GRO WGHT EC50 21 d 0.03471 lb/acre 100 156993

Clethodim Cynodon sp. Bermudagrass GRO GRO VGOR IC50 31 d 0.03568 lb/acre 100 155802

Clethodim Cynodon sp. Bermudagrass GRO GRO VGOR IC50 31 d 0.03568 lb/acre 100 155802

Clethodim Cynodon sp. Bermudagrass GRO GRO VGOR IC50 31 d 0.03568 lb/acre 100 155802

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP CNTL IC80 21 d 0.03738 lb/acre 100 156893

Clethodim Hordeum jubatum Foxtail Barley POP POP BMAS LOAEL 1 gs 0.04005 lb/acre 100 63023

Clethodim Hordeum jubatum Foxtail Barley POP POP BMAS LOAEL 1 gs 0.04005 lb/acre 100 63023

Clethodim Linum usitatissimum Flax POP POP BMAS NOAEL hv 0.04005 lb/acre 100 63023

Clethodim Hordeum jubatum Foxtail Barley POP POP BMAS LOAEL 1 gs 0.04005 lb/acre 100 63023

Clethodim Hordeum jubatum Foxtail Barley POP POP BMAS LOAEL 1 gs 0.04005 lb/acre 100 63023

Clethodim Hordeum jubatum Foxtail Barley POP POP BMAS LOAEL 1 gs 0.04005 lb/acre 100 63023

Clethodim Hordeum jubatum Foxtail Barley POP POP BMAS LOAEL 1 gs 0.04005 lb/acre 100 63023

Clethodim Linum usitatissimum Flax POP POP BMAS LOAEL hv 0.04005 lb/acre 100 63023

Clethodim Linum usitatissimum Flax POP POP BMAS NOAEL hv 0.04005 lb/acre 100 63023

Clethodim Linum usitatissimum Flax POP POP BMAS NOAEL hv 0.04005 lb/acre 100 63023

Clethodim Elymus repens Quackgrass POP POP BMAS LOAEL 45.66 d 0.04005 lb/acre 100 156933

Clethodim Elymus repens Quackgrass POP POP BMAS LOAEL 45.66 d 0.04005 lb/acre 100 156933

Clethodim Elymus repens Quackgrass POP POP BMAS LOAEL 45.66 d 0.04005 lb/acre 100 156933

Clethodim Elymus repens Quackgrass POP POP BMAS LOAEL 45.66 d 0.04005 lb/acre 100 156933

Clethodim Elymus repens Quackgrass POP POP BMAS LOAEL 45.66 d 0.04005 lb/acre 100 156933

Clethodim Linum usitatissimum Flax POP POP BMAS LOAEL 85 d 0.04005 lb/acre 100 156933

Clethodim Phalaris paradoxa Hood

Canarygrass GRO GRO WGHT ED50 21 d 0.04094 lb/acre 100 156947

Clethodim NR Magnoliopsida Dicot Class POP POP ABND NOAEL 42 d 0.04272 lb/acre 100 150459

Clethodim Lolium rigidum Wimmera

Ryegrass POP POP ABND LOAEL 42 d 0.04272 lb/acre 100 150459

Clethodim NR Poaceae Grass Family POP POP ABND NOAEL 42 d 0.04272 lb/acre 100 150459

Clethodim Sorghum halepense Johnson Grass GRO GRO WGHT EC50 28 d 0.044322 lb/acre 100 66802

Clethodim Eleusine indica Goosegrass POP POP BMAS LOAEL 21 d 0.0445 lb/acre 100 156975

Clethodim Eleusine indica Goosegrass POP POP BMAS LOAEL 21 d 0.0445 lb/acre 100 156975

Clethodim Avena fatua Red Oats POP POP WGHT NOAEL LOAEL hv 0.0445 lb/acre 100 157105

Clethodim Hordeum vulgare Barley POP POP WGHT NOAEL LOAEL hv 0.0445 lb/acre 100 157105

Clethodim Hordeum vulgare Barley POP POP WGHT NOAEL LOAEL hv 0.0445 lb/acre 100 157105

Clethodim Cynodon sp. Bermudagrass PHY INJ DAMG IC50 17 d 0.0446 lb/acre 100 155802

Clethodim Cynodon sp. Bermudagrass GRO GRO VGOR IC50 17 d 0.0446 lb/acre 100 155802

## 121 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Setaria faberi Mutton

Bluegrass MOR MOR SURV LOAEL 21 d 0.046725 lb/acre 100 157078

Clethodim NR Poaceae Grass Family POP POP CNTL LOAEL 14 d 0.04717 lb/acre 100 156984

Clethodim NR Poaceae Grass Family POP POP CNTL LOAEL 14 d 0.04717 lb/acre 100 156984

Clethodim NR Poaceae Grass Family POP POP CNTL LOAEL 14 d 0.04717 lb/acre 100 156984

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04717 lb/acre 100 156984

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04717 lb/acre 100 156984

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04717 lb/acre 100 156984

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04717 lb/acre 100 156984

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.04984 lb/acre 100 157069

Clethodim Cynodon dactylon Bermudagrass GRO GRO VGOR IC50 31 d 0.05352 lb/acre 100 155802

Clethodim Phalaris paradoxa Hood

Canarygrass GRO GRO WGHT ED50 21 d 0.056515 lb/acre 100 156947

Clethodim Hordeum murinum ssp.

leporinum Leporinum

Barley POP POP BMAS ED50 42 d 0.057939 lb/acre 100 157040

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 14 d 0.05874 lb/acre 100 157076

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 14 d 0.05874 lb/acre 100 157076

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 14 d 0.05874 lb/acre 100 157076

## 122 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Gossypium hirsutum Cotton POP POP BMAS NOAEL hv 0.05874 lb/acre 100 157076

Clethodim Bromus diandrus Ripgut Brome POP POP BMAS ED50 42 d 0.059007 lb/acre 100 157040

Clethodim Avena fatua Red Oats POP POP BMAS ED50 42 d 0.060164 lb/acre 100 157040

Clethodim Sorghum halepense Johnson Grass GRO GRO WGHT EC50 28 d 0.061499 lb/acre 100 66802

Clethodim Sorghum halepense Johnson Grass POP POP BMAS LOAEL 1 gs 0.0623 lb/acre 100 63480

Clethodim Sorghum halepense Johnson Grass POP POP BMAS LOAEL 1 gs 0.0623 lb/acre 100 63480

Clethodim Sorghum halepense Johnson Grass POP POP BMAS LOAEL 1 gs 0.0623 lb/acre 100 63480

Clethodim Sorghum halepense Johnson Grass POP POP ABND LOAEL 1 gs 0.0623 lb/acre 100 63480

Clethodim Sorghum halepense Johnson Grass POP POP ABND LOAEL 1 gs 0.0623 lb/acre 100 63480

Clethodim Sorghum halepense Johnson Grass POP POP ABND NOAEL LOAEL 1 gs 0.0623 lb/acre 100 63480

Clethodim Sorghum halepense Johnson Grass POP POP ABND LOAEL 1 gs 0.0623 lb/acre 100 63480

Clethodim Sorghum halepense Johnson Grass POP POP ABND LOAEL 1 gs 0.0623 lb/acre 100 63480

Clethodim Oryza sativa Rice POP POP BMAS NOAEL d 0.0623 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP BMAS NOAEL d 0.0623 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP BMAS LOAEL d 0.0623 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP BMAS LOAEL d 0.0623 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP BMAS LOAEL d 0.0623 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP BMAS LOAEL d 0.0623 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP BMAS NOAEL d 0.0623 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP BMAS NOAEL d 0.0623 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP BMAS LOAEL d 0.0623 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP BMAS LOAEL d 0.0623 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP BMAS LOAEL d 0.0623 lb/acre 100 59315

Clethodim Eriochloa villosa Hairy Cupgrass POP POP CNTL LOAEL 16 d 0.06244 lb/acre 100 116575

Clethodim Cynodon sp. Bermudagrass GRO GRO VGOR IC50 31 d 0.06244 lb/acre 100 155802

Clethodim Cynodon sp. Bermudagrass GRO GRO VGOR IC50 31 d 0.06244 lb/acre 100 155802

Clethodim Cynodon sp. Bermudagrass GRO GRO VGOR IC50 31 d 0.06244 lb/acre 100 155802

Clethodim Cynodon sp. Bermudagrass GRO GRO VGOR IC50 31 d 0.06244 lb/acre 100 155802

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP BMAS LOAEL 28 d 0.06244 lb/acre 100 157113

Clethodim Bromus tectorum Downy Brome MOR MOR MORT NR

LETH 47 d 0.06244 lb/acre 100 157092

Clethodim Bromus tectorum Downy Brome GRO GRO BMAS EC50 47 d 0.06244 lb/acre 100 157092

Clethodim Urochloa texana Texas Signalgrass POP POP CNTL LOAEL 88 d 0.06244 lb/acre 100 156970

Clethodim Urochloa texana Texas Signalgrass POP POP CNTL LOAEL 75 d 0.06244 lb/acre 100 156970

Clethodim Urochloa texana Texas Signalgrass POP POP CNTL LOAEL 74 d 0.06244 lb/acre 100 156970

Clethodim Urochloa texana Texas Signalgrass POP POP CNTL LOAEL 53 d 0.06244 lb/acre 100 156970

Clethodim Setaria faberi Mutton

Bluegrass POP POP BMAS LOAEL 21 d 0.06319 lb/acre 100 64012

Clethodim NR Magnoliopsida Dicot Class POP POP ABND LOAEL 21 d 0.06408 lb/acre 25 157118

Clethodim NR Poaceae Grass Family POP POP BMAS LOAEL 21 d 0.06408 lb/acre 25 157118

## 123 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim NR Plantae Plant Kingdom POP POP ABND LOAEL 21 d 0.06408 lb/acre 25 157118

Clethodim Glycine max Soybean POP POP BMAS NOAEL 21 d 0.06408 lb/acre 25 157118

Clethodim Bromus tectorum Downy Brome GRO GRO WGHT ED50 21 d 0.06586 lb/acre 100 154031

Clethodim Elymus repens Quackgrass POP POP CNTL LOAEL 1 gs 0.0669 lb/acre 100 82407

Clethodim Elymus repens Quackgrass POP POP CNTL LOAEL 1 gs 0.0669 lb/acre 100 82407

Clethodim NR Poaceae Grass Family POP POP CNTL LOAEL 7 d 0.07136 lb/acre 100 120431

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 19 d 0.07136 lb/acre 100 120431

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 19 d 0.07136 lb/acre 100 120431

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 18 d 0.07136 lb/acre 100 120431

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP BMAS LOAEL 50 d 0.07136 lb/acre 100 120431

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 19 d 0.07136 lb/acre 100 120431

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 18 d 0.07136 lb/acre 100 120431

Clethodim Agrostis castellana Bentgrass PHY INJ DAMG LOAEL 49 d 0.07136 lb/acre 100 70295

Clethodim Cynodon sp. Bermudagrass PHY INJ DAMG IC50 17 d 0.07136 lb/acre 100 155802

Clethodim Cynodon sp. Bermudagrass GRO GRO VGOR IC50 31 d 0.07136 lb/acre 100 155802

Clethodim Cynodon sp. Bermudagrass PHY INJ DAMG IC50 17 d 0.07136 lb/acre 100 155802

Clethodim Hordeum murinum ssp.

leporinum Leporinum

Barley MOR MOR MORT LD50 35 d 0.07832 lb/acre 100 63953

Clethodim Linum usitatissimum Flax POP POP BMAS NOAEL 81 d 0.0801 lb/acre 100 156933

Clethodim Linum usitatissimum Flax POP POP BMAS NOAEL 89 d 0.0801 lb/acre 100 156933

Clethodim Linum usitatissimum Flax POP POP BMAS NOAEL 78 d 0.0801 lb/acre 100 156933

Clethodim Linum usitatissimum Flax POP POP BMAS NOAEL 90 d 0.0801 lb/acre 100 156933

Clethodim Cynodon sp. Bermudagrass PHY INJ DAMG IC50 17 d 0.08028 lb/acre 100 155802

Clethodim Cynodon sp. Bermudagrass GRO GRO VGOR IC50 31 d 0.08028 lb/acre 100 155802

Clethodim Cynodon dactylon Bermudagrass PHY INJ DAMG IC50 17 d 0.08028 lb/acre 100 155802

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 13 d 0.08028 lb/acre 100 73962

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 17 d 0.08028 lb/acre 100 73962

Clethodim Lolium rigidum Wimmera

Ryegrass MOR MOR MORT LD50 21 d 0.08722 lb/acre 100 111509

Clethodim Urochloa texana Texas Signalgrass POP POP CNTL LOAEL 62 d 0.0892 lb/acre 100 67060

Clethodim Urochloa texana Texas Signalgrass POP POP CNTL LOAEL 62 d 0.0892 lb/acre 100 67060

Clethodim Dactyloctenium aegyptium Crowfoot Grass POP POP CNTL LOAEL 62 d 0.0892 lb/acre 100 67060

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL hv 0.0892 lb/acre 100 67060

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL hv 0.0892 lb/acre 100 67060

Clethodim Digitaria ciliaris Smooth

Crabgrass POP POP CNTL LOAEL 62 d 0.0892 lb/acre 100 67060

Clethodim Digitaria ciliaris Smooth

Crabgrass POP POP CNTL LOAEL 62 d 0.0892 lb/acre 100 67060

Clethodim Urochloa texana Texas Signalgrass POP POP CNTL LOAEL 62 d 0.0892 lb/acre 100 67060

Clethodim Digitaria ciliaris Smooth POP POP CNTL LOAEL 62 d 0.0892 lb/acre 100 67060

## 124 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Crabgrass

Clethodim Dactyloctenium aegyptium Crowfoot Grass POP POP CNTL LOAEL 62 d 0.0892 lb/acre 100 67060

Clethodim Dactyloctenium aegyptium Crowfoot Grass POP POP CNTL LOAEL 62 d 0.0892 lb/acre 100 67060

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL hv 0.0892 lb/acre 100 67060

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL hv 0.0892 lb/acre 100 67060

Clethodim Oryza sativa Rice POP POP CNTL LOAEL ea 0.0892 lb/acre 100 73747

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.0892 lb/acre 100 73747

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.0892 lb/acre 100 73747

Clethodim Setaria viridis Green Foxtail POP POP BMAS LOAEL 21 d 0.0892 lb/acre 100 120455

Clethodim Setaria viridis Green Foxtail POP POP BMAS LOAEL 21 d 0.0892 lb/acre 100 120455

Clethodim Avena fatua Red Oats POP POP BMAS LOAEL 21 d 0.0892 lb/acre 100 120455

Clethodim Avena fatua Red Oats POP POP BMAS LOAEL 21 d 0.0892 lb/acre 100 120455

Clethodim Avena fatua Red Oats POP POP BMAS LOAEL 1 gs 0.0892 lb/acre 100 120455

Clethodim Avena fatua Red Oats POP POP BMAS LOAEL 1 gs 0.0892 lb/acre 100 120455

Clethodim Carthamus tinctorius Safflower POP POP BMAS NOAEL hv 0.0892 lb/acre 100 120455

Clethodim Carthamus tinctorius Safflower POP POP BMAS NOAEL hv 0.0892 lb/acre 100 120455

Clethodim Carthamus tinctorius Safflower POP POP BMAS NOAEL hv 0.0892 lb/acre 100 120455

Clethodim Carthamus tinctorius Safflower POP POP BMAS NOAEL hv 0.0892 lb/acre 100 120455

Clethodim Carthamus tinctorius Safflower PHY INJ DAMG NOAEL 21 d 0.0892 lb/acre 100 120455

Clethodim Sorghum halepense Johnson Grass PHY INJ DAMG LOAEL 21 d 0.0892 lb/acre 100 155808

Clethodim Sorghum halepense Johnson Grass PHY INJ DAMG LOAEL 21 d 0.0892 lb/acre 100 155808

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL hv 0.0892 lb/acre 100 120386

Clethodim Cynodon sp. Bermudagrass GRO GRO VGOR IC50 31 d 0.0892 lb/acre 100 155802

Clethodim Urochloa texana Texas Signalgrass POP POP CNTL LOAEL 90 d 0.09 AI lb/acre 100 156906

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.09345 lb/acre 100 156984

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.09345 lb/acre 100 156984

Clethodim Lolium rigidum Wimmera

Ryegrass MOR MOR MORT LD50 21 d 0.09345 lb/acre 100 111509

Clethodim Setaria faberi Mutton

Bluegrass MOR MOR MORT NR

LETH 21 d 0.09345 lb/acre 100 157078

Clethodim Urochloa platyphylla Broadleaf

Signalgrass POP POP CNTL LOAEL 14 d 0.09345 lb/acre 100 157073

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 14 d 0.09345 lb/acre 100 157073

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 14 d 0.09345 lb/acre 100 157073

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 14 d 0.09345 lb/acre 100 157073

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 14 d 0.09345 lb/acre 100 157073

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 14 d 0.09345 lb/acre 100 157073

Clethodim Urochloa platyphylla Broadleaf

Signalgrass POP POP CNTL LOAEL 14 d 0.09345 lb/acre 100 157073

Clethodim Urochloa platyphylla Broadleaf POP POP CNTL LOAEL 14 d 0.09434 lb/acre 100 156884

## 125 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Signalgrass

Clethodim Echinochloa crus

- galli Barnyard Grass POP POP CNTL LOAEL 14 d 0.09434 lb/acre 100 156884

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.09434 lb/acre 100 156884

Clethodim Glycine max Soybean PHY INJ GINJ NOAEL 27 d 0.094552 lb/acre 100 73962

Clethodim Glycine max Soybean POP POP BMAS NOAEL 121 d 0.094552 lb/acre 100 73962

Clethodim Glycine max Soybean PHY INJ GINJ NOAEL 87 d 0.094552 lb/acre 100 73962

Clethodim Oryza sativa Rice POP POP BMAS LOAEL d 0.0979 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP BMAS LOAEL d 0.0979 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP BMAS LOAEL d 0.0979 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP BMAS NOAEL d 0.0979 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP BMAS LOAEL d 0.0979 lb/acre 100 59315

Clethodim Oryza sativa Rice POP POP CNTL LOAEL 28 d 0.0979 lb/acre 100 63442

Clethodim Oryza sativa Rice POP POP CNTL LOAEL 28 d 0.0979 lb/acre 100 63442

Clethodim Oryza sativa Rice POP POP CNTL LOAEL 28 d 0.0979 lb/acre 100 63442

Clethodim Sorghum halepense Johnson Grass GRO GRO WGHT EC50 21 d 0.0979 lb/acre 100 156993

Clethodim Hibiscus cannabinus Deccan Hemp GRO GRO HGHT NOAEL 26 d 0.0979 lb/acre 100 157110

Clethodim Hibiscus cannabinus Deccan Hemp PHY INJ GINJ NOAEL 10 d 0.0979 lb/acre 100 157110

Clethodim Hibiscus cannabinus Deccan Hemp PHY INJ GINJ NOAEL 10 d 0.0979 lb/acre 100 157110

Clethodim Hibiscus cannabinus Deccan Hemp GRO GRO HGHT NOAEL 26 d 0.0979 lb/acre 100 157110

Clethodim Urochloa texana Texas Signalgrass POP POP CNTL LOAEL 79 d 0.09812 lb/acre 100 156970

Clethodim Digitaria ciliaris Smooth

Crabgrass POP POP CNTL LOAEL 79 d 0.09812 lb/acre 100 156970

Clethodim Digitaria ciliaris Smooth

Crabgrass POP POP CNTL LOAEL 74 d 0.09812 lb/acre 100 156970

Clethodim Xanthium strumarium Common

Cocklebur POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Glycine max Soybean PHY INJ GINJ NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Glycine max Soybean POP POP BMAS NOAEL 138 d 0.09812 lb/acre 100 157119

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP CNTL LOAEL 10 d 0.09812 lb/acre 100 157119

Clethodim Amaranthus hybridus Green Amaranth POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Ipomoea lacunosa White

Morninglory POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Ipomoea hederacea Ivyleaf Morning

- Glory POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Sesbania herbacea Colorado

- River

-

Hemp POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Sida spinosa Prickly Mallow POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Xanthium strumarium Common

Cocklebur POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Glycine max Soybean PHY INJ GINJ NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Glycine max Soybean POP POP BMAS NOAEL 145 d 0.09812 lb/acre 100 157119

## 126 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Amaranthus hybridus Green Amaranth POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP CNTL LOAEL 10 d 0.09812 lb/acre 100 157119

Clethodim Ipomoea lacunosa White

Morninglory POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Ipomoea hederacea Ivyleaf Morning

- Glory POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Sesbania herbacea Colorado

- River

-

Hemp POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Sida spinosa Prickly Mallow POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP CNTL LOAEL 14 d 0.09812 lb/acre 100 157119

Clethodim Amaranthus hybridus Green Amaranth POP POP CNTL NOAEL 32 d 0.09812 lb/acre 100 157119

Clethodim Sesbania herbacea Colorado

- River

-

Hemp POP POP CNTL NOAEL 32 d 0.09812 lb/acre 100 157119

Clethodim Sida spinosa Prickly Mallow POP POP CNTL NOAEL 32 d 0.09812 lb/acre 100 157119

Clethodim Amaranthus hybridus Green Amaranth POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Ipomoea lacunosa White

Morninglory POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Ipomoea hederacea Ivyleaf Morning

- Glory POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Sesbania herbacea Colorado

- River

-

Hemp POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Sida spinosa Prickly Mallow POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Glycine max Soybean PHY INJ GINJ NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Glycine max Soybean POP POP BMAS NOAEL 153 d 0.09812 lb/acre 100 157119

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP CNTL LOAEL 10 d 0.09812 lb/acre 100 157119

Clethodim Ipomoea lacunosa White

Morninglory POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Ipomoea hederacea Ivyleaf Morning

- Glory POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Sesbania herbacea Colorado

- River

-

Hemp POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Sida spinosa Prickly Mallow POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Abutilon theophrasti Butter Print POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Xanthium strumarium Common

Cocklebur POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Glycine max Soybean PHY INJ GINJ NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Glycine max Soybean POP POP BMAS NOAEL 150 d 0.09812 lb/acre 100 157119

Clethodim Abutilon theophrasti Butter Print POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Xanthium strumarium Common

Cocklebur POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Ipomoea lacunosa White POP POP CNTL NOAEL 32 d 0.09812 lb/acre 100 157119

## 127 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Morninglory

Clethodim Ipomoea hederacea Ivyleaf Morning

- Glory POP POP CNTL NOAEL 32 d 0.09812 lb/acre 100 157119

Clethodim Glycine max Soybean PHY INJ GINJ NOAEL 32 d 0.09812 lb/acre 100 157119

Clethodim Glycine max Soybean POP POP BMAS NOAEL 138 d 0.09812 lb/acre 100 157119

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP CNTL LOAEL 10 d 0.09812 lb/acre 100 157119

Clethodim Abutilon theophrasti Butter Print POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Xanthium strumarium Common

Cocklebur POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Amaranthus hybridus Green Amaranth POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP CNTL LOAEL 10 d 0.09812 lb/acre 100 157119

Clethodim Amaranthus hybridus Green Amaranth POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Ipomoea lacunosa White

Morninglory POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Ipomoea hederacea Ivyleaf Morning

- Glory POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Sesbania herbacea Colorado

- River

-

Hemp POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Sida spinosa Prickly Mallow POP POP CNTL NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Glycine max Soybean PHY INJ GINJ NOAEL 28 d 0.09812 lb/acre 100 157119

Clethodim Glycine max Soybean POP POP BMAS NOAEL 154 d 0.09812 lb/acre 100 157119

Clethodim Xanthium strumarium Common

Cocklebur POP POP CNTL NOAEL 32 d 0.09812 lb/acre 100 157119

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.09968 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.09968 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.09968 lb/acre 100 157069

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.09968 lb/acre 100 157069

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP CNTL LOAEL 21 d 0.099904 lb/acre 100 157082

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP CNTL LOAEL 21 d 0.099904 lb/acre 100 157082

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP CNTL LOAEL 9 d 0.099904 lb/acre 100 157082

Clethodim Lolium rigidum Wimmera

Ryegrass MOR MOR MORT LD50 21 d 0.10235 lb/acre 100 111509

Clethodim Vulpia myuros Foxtail Fescue POP POP BMAS ED50 42 d 0.10413 lb/acre 100 157040

Clethodim Chloris elata Tall Windmill

Grass POP POP BMAS LOAEL 16 d 0.1068 lb/acre 100 156939

Clethodim Elymus repens Quackgrass POP POP CNTL LOAEL 1 gs 0.10704 lb/acre 100 82407

Clethodim Cynodon sp. Bermudagrass PHY INJ DAMG IC50 17 d 0.10704 lb/acre 100 155802

Clethodim Cynodon sp. Bermudagrass PHY INJ DAMG IC50 17 d 0.10704 lb/acre 100 155802

Clethodim Desmanthus virgatus Wild Tantan POP POP WGHT NOAEL 35 d 0.10704 lb/acre 100 157094

Clethodim Cicer arietinum Chick Pea POP POP DBMS NOAEL 107 d 0.10704 lb/acre 100 120308

Clethodim Cicer arietinum Chick Pea POP POP DBMS NOAEL 107 d 0.10704 lb/acre 100 120308

## 128 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Cicer arietinum Chick Pea POP POP DBMS NOAEL 22 d 0.10704 lb/acre 100 120308

Clethodim NR Plantae Plant Kingdom POP POP DBMS NOAEL 22 d 0.10704 lb/acre 100 120308

Clethodim Phragmites australis Grass POP POP CNTL LOAEL 35 d 0.11596 lb/acre 100 103875

Clethodim Phragmites australis Grass GRO MPH WGHT NOAEL 70 d 0.11596 lb/acre 100 103875

Clethodim Phyllostachys aurea Golden Bamboo PHY INJ DAMG NOAEL 28 d 0.11596 lb/acre 100 154909

Clethodim Phyllostachys aurea Golden Bamboo GRO GRO WGHT NOAEL 42 d 0.11596 lb/acre 100 154909

Clethodim Cynodon sp. Bermudagrass PHY INJ DAMG IC50 17 d 0.11596 lb/acre 100 155802

Clethodim Gossypium hirsutum Cotton POP POP BMAS NOAEL 1 gs 0.1246 lb/acre 100 63480

Clethodim Gossypium hirsutum Cotton POP POP BMAS NOAEL 1 gs 0.1246 lb/acre 100 63480

Clethodim Gossypium hirsutum Cotton POP POP BMAS NOAEL 1 gs 0.1246 lb/acre 100 63480

Clethodim Gossypium hirsutum Cotton POP POP BMAS NOAEL 1 gs 0.1246 lb/acre 100 63480

Clethodim Gossypium hirsutum Cotton POP POP BMAS NOAEL 1 gs 0.1246 lb/acre 100 63480

Clethodim Gossypium hirsutum Cotton POP POP BMAS NOAEL 1 gs 0.1246 lb/acre 100 63480

Clethodim Gossypium hirsutum Cotton POP POP BMAS NOAEL 1 gs 0.1246 lb/acre 100 63480

Clethodim Gossypium hirsutum Cotton POP POP BMAS NOAEL 1 gs 0.1246 lb/acre 100 63480

Clethodim Gossypium hirsutum Cotton POP POP BMAS NOAEL 1 gs 0.1246 lb/acre 100 63480

Clethodim Poa sp. Bluegrass PHY INJ DAMG LOAEL 14 d 0.1246 lb/acre 100 154952

Clethodim Poa sp. Bluegrass GRO GRO VGOR LOAEL 14 d 0.1246 lb/acre 100 154952

Clethodim Poa sp. Bluegrass BCM BCM CHLO LOAEL 14 d 0.1246 lb/acre 100 154952

Clethodim Zea mays Corn GRO GRO HGHT LOAEL 14 d 0.1246 lb/acre 100 64012

Clethodim Zea mays Corn GRO GRO WGHT LOAEL 14 d 0.1246 lb/acre 100 64012

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 77 d 0.1246 lb/acre 100 157103

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 72 d 0.1246 lb/acre 100 157103

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 77 d 0.1246 lb/acre 100 157103

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 102 d 0.1246 lb/acre 100 157103

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 72 d 0.1246 lb/acre 100 157103

Clethodim Sorghum bicolor ssp.

bicolor Grain Sorghum GRO GRO HGHT LOAEL 21 d 0.1246 lb/acre 100 64012

Clethodim Sorghum bicolor ssp.

bicolor Grain Sorghum GRO GRO WGHT LOAEL 21 d 0.1246 lb/acre 100 64012

Clethodim Digitaria sanguinalis Purple Crabgrass GRO GRO HGHT LOAEL 21 d 0.1246 lb/acre 100 64012

Clethodim Digitaria sanguinalis Purple Crabgrass GRO GRO WGHT LOAEL 21 d 0.1246 lb/acre 100 64012

Clethodim Sorghum halepense Johnson Grass PHY PHY STOC ET50 6.1 d 0.1246 lb/acre 100 157102

Clethodim Sorghum halepense Johnson Grass PHY PHY CASS ET50 6.5 d 0.1246 lb/acre 100 157102

Clethodim Glycine max Soybean PHY INJ GINJ NOAEL 16 d 0.12488 lb/acre 100 116575

Clethodim Glyceria declinata Waxy

Mannagrass POP POP CNTL LOAEL 7 d 0.12488 lb/acre 100 96386

Clethodim Luziola fluitans Southern

Watergrass POP POP CNTL LOAEL 35 d 0.12488 lb/acre 100 96386

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 91.32 d 0.12488 lb/acre 100 156971

## 129 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Urochloa texana Texas Signalgrass POP POP CNTL LOAEL 60 d 0.12488 lb/acre 100 156970

Clethodim Digitaria ciliaris Smooth

Crabgrass POP POP CNTL LOAEL 53 d 0.12488 lb/acre 100 156970

Clethodim Digitaria ciliaris Smooth

Crabgrass POP POP CNTL LOAEL 60 d 0.12488 lb/acre 100 156970

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL 116 d 0.12488 lb/acre 100 156970

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL 103 d 0.12488 lb/acre 100 156970

Clethodim Arachis hypogaea Peanut POP POP CNTL NOAEL 102 d 0.12488 lb/acre 100 156970

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL 81 d 0.12488 lb/acre 100 156970

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL 107 d 0.12488 lb/acre 100 156970

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL 88 d 0.12488 lb/acre 100 156970

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL d 0.12488 lb/acre 100 157020

Clethodim Cynodon sp. Bermudagrass PHY INJ DAMG IC50 17 d 0.12488 lb/acre 100 155802

Clethodim Bromus tectorum Downy Brome MOR MOR MORT NOAEL 47 d 0.12488 lb/acre 100 157092

Clethodim Bromus tectorum Downy Brome MOR MOR MORT NR

ZERO 47 d 0.12488 lb/acre 100 157092

Clethodim Geranium sp. Geranium PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Ageratum sp. Whiteweed PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Alyssum sp. Alyssum PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Aster sp. Aster PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Celosia sp. Cock's Comb PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Dahlia sp. Dahlia PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Dianthus sp. Pink PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Hibiscus sp. Hibiscus PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Impatiens sp. Touchmenot PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Tagetes sp. Marigold PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Tagetes sp. Marigold PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Nicotiana sp. Tobacco PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Capsicum sp. Pepper PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Petunia sp. Petunia PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Petunia sp. Petunia PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Salvia sp. Salvia PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Salvia sp. Salvia PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Antirrhinum sp. Snapdragon PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Vinca sp. Periwinkle PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Zinnia sp. Zinnia PHY INJ DAMG NOAEL 49 d 0.12488 lb/acre 100 155813

Clethodim Ageratum houstonianum Ageratum PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Lobularia maritima Sweet Alyssum PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Callistephus chinensis China Aster PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Celosia cristata Crested Cock's PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

## 130 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Comb

Clethodim Coreopsis lanceolata Lanceleaf

Tickseed PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Dahlia sp. Dahlia PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Dianthus barbatus Sweet

- William PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Pelargonium x hortorum Zonal Geranium PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Hibiscus moscheutos Crimsoneyed

Rosemallow PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Impatiens walleriana Busy Lizzy PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Tagetes patula French Marigold PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Tagetes patula French Marigold PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Nicotiana alata Jasmine Tobacco PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Capsicum annuum Bell Pepper PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Petunia x hybrida Petunia PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Petunia x hybrida Petunia PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Salvia farinacea Mealycup Sage PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Salvia splendens Scarlet Sage PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Antirrhinum majus Snapdragon PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Catharanthus roseus Bright

- Eyes PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Zinnia violacea Zinnia PHY INJ DAMG NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Digitaria sanguinalis Purple Crabgrass POP POP CNTL LOAEL 14 d 0.12488 lb/acre 100 70759

Clethodim Amaranthus sp. Amaranth POP POP CNTL NOAEL 56 d 0.12488 lb/acre 100 70759

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 14 d 0.12488 lb/acre 100 157119

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 7 d 0.125 lb/acre 100 156937

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 7 d 0.125 lb/acre 100 156937

Clethodim Medicago sativa Alfalfa POP POP BMAS NOAEL 70 d 0.12816 lb/acre 100 67066

Clethodim NR Plantae Plant Kingdom POP POP BMAS LOAEL 20 d 0.12816 lb/acre 100 67066

Clethodim Medicago sativa Alfalfa POP POP BMAS NOAEL 20 d 0.12816 lb/acre 100 67066

Clethodim NR Plantae Plant Kingdom POP POP BMAS LOAEL 20 d 0.12816 lb/acre 100 67066

Clethodim Medicago sativa Alfalfa POP POP BMAS NOAEL 170 d 0.12816 lb/acre 100 67066

Clethodim NR Plantae Plant Kingdom POP POP BMAS LOAEL 170 d 0.12816 lb/acre 100 67066

Clethodim Medicago sativa Alfalfa POP POP BMAS NOAEL 70 d 0.12816 lb/acre 100 67066

Clethodim NR Plantae Plant Kingdom POP POP BMAS LOAEL 70 d 0.12816 lb/acre 100 67066

Clethodim Medicago sativa Alfalfa POP POP BMAS NOAEL 70 d 0.12816 lb/acre 100 67066

Clethodim NR Plantae Plant Kingdom POP POP BMAS LOAEL 70 d 0.12816 lb/acre 100 67066

Clethodim Elymus repens Quackgrass POP POP CNTL LOAEL 1 gs 0.1338 lb/acre 100 82407

Clethodim Cynodon sp. Bermudagrass POP POP CNTL LOAEL 133 d 0.1338 lb/acre 100 156935

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 133 d 0.1338 lb/acre 100 156935

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 133 d 0.1338 lb/acre 100 156935

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL NOAEL LOAEL 133 d 0.1338 lb/acre 100 156935

## 131 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.13884 lb/acre 100 157073

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.13884 lb/acre 100 157073

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.13884 lb/acre 100 157073

Clethodim Lolium rigidum Wimmera

Ryegrass PHY INJ DAMG LOAEL 15 d 0.15 L/ha 100 86670

Clethodim Lolium rigidum Wimmera

Ryegrass GRO GRO NLEF LOAEL 30 d 0.15 L/ha 100 86670

Clethodim Avena sativa Common Oat GRO GRO NLEF LOAEL 30 d 0.15 L/ha 100 86670

Clethodim Avena sativa Common Oat PHY INJ DAMG LOAEL 15 d 0.15 L/ha 100 86670

Clethodim Dactylis glomerata Orchardgrass GRO GRO NLEF LOAEL 30 d 0.15 L/ha 100 86670

Clethodim Dactylis glomerata Orchardgrass PHY INJ DAMG LOAEL 15 d 0.15 L/ha 100 86670

Clethodim Schedonorus arundinaceus Tall Fescue PHY INJ DAMG LOAEL 15 d 0.15 L/ha 100 86670

Clethodim Schedonorus arundinaceus Tall Fescue GRO GRO NLEF LOAEL 30 d 0.15 L/ha 100 86670

Clethodim Lolium perenne Perennial

Ryegrass PHY INJ DAMG LOAEL 15 d 0.15 L/ha 100 86670

Clethodim Lolium perenne Perennial

Ryegrass GRO GRO NLEF LOAEL 30 d 0.15 L/ha 100 86670

Clethodim Triticum aestivum Bread Wheat PHY INJ DAMG LOAEL 15 d 0.15 L/ha 100 86670

Clethodim Triticum aestivum Bread Wheat GRO GRO WGHT LOAEL 30 d 0.15 L/ha 100 86670

Clethodim Phalaris aquatica Kolea Grass GRO GRO NLEF LOAEL 30 d 0.15 L/ha 100 86670

Clethodim Phalaris aquatica Kolea Grass PHY INJ DAMG LOAEL 15 d 0.15 L/ha 100 86670

Clethodim Trifolium subterraneum Subterranean

Clover PHY INJ DAMG NOAEL 30 d 0.15 L/ha 100 86670

Clethodim Trifolium subterraneum Subterranean

Clover GRO GRO NLEF NOAEL 30 d 0.15 L/ha 100 86670

Clethodim Rytidosperma richardsonii Wallaby Grass GRO GRO NLEF LOAEL 30 d 0.15 L/ha 100 86670

Clethodim Rytidosperma richardsonii Wallaby Grass PHY INJ DAMG LOAEL 15 d 0.15 L/ha 100 86670

Clethodim Festuca rubra Ravine Fescue PHY INJ DAMG NOAEL 49 d 0.15164 lb/acre 100 70295

Clethodim Festuca trachyphylla Hard Fescue PHY INJ DAMG NOAEL 49 d 0.15164 lb/acre 100 70295

Clethodim Cynodon sp. Bermudagrass PHY INJ DAMG IC50 17 d 0.15164 lb/acre 100 155802

Clethodim Bromus tectorum Downy Brome GRO GRO BMAS EC50 47 d 0.15164 lb/acre 100 157092

Clethodim Medicago sativa Alfalfa POP POP BMAS NOAEL 730 d 0.16056 lb/acre 100 157070

Clethodim Medicago sativa Alfalfa POP POP BMAS NOAEL 730 d 0.16056 lb/acre 100 157070

Clethodim Elymus repens Quackgrass POP POP BMAS LOAEL 365 d 0.16056 lb/acre 100 157070

Clethodim Elymus repens Quackgrass POP POP BMAS LOAEL 730 d 0.16056 lb/acre 100 157070

Clethodim Elymus repens Quackgrass POP POP BMAS NOAEL 1095 d 0.16056 lb/acre 100 157070

Clethodim Cynodon sp. Bermudagrass PHY INJ DAMG IC50 17 d 0.16056 lb/acre 100 155802

Clethodim Cynodon sp. Bermudagrass PHY INJ DAMG IC50 17 d 0.16948 lb/acre 100 155802

Clethodim Eriochloa contracta Prairie cupgrass REP REP VEGR LOAEL 28 d 0.1869 lb/acre 100 157106

## 132 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Chloris verticillata Tumble windmill

grass REP REP VEGR LOAEL 28 d 0.1869 lb/acre 100 157106

Clethodim Eriochloa contracta Prairie cupgrass REP REP VEGR LOAEL 28 d 0.1869 lb/acre 100 157106

Clethodim Chloris verticillata Tumble windmill

grass REP REP VEGR LOAEL 28 d 0.1869 lb/acre 100 157106

Clethodim Eriochloa contracta Prairie cupgrass REP REP VEGR LOAEL 28 d 0.1869 lb/acre 100 157106

Clethodim Chloris verticillata Tumble windmill

grass REP REP VEGR LOAEL 28 d 0.1869 lb/acre 100 157106

Clethodim NR Plantae Plant Kingdom POP POP COVR LOAEL 1 gs 0.18732 lb/acre 100 156982

Clethodim NR Plantae Plant Kingdom POP POP DVRS NOAEL 1 gs 0.18732 lb/acre 100 156982

Clethodim NR Plantae Plant Kingdom POP POP COVR NOAEL 2 gs 0.18732 lb/acre 100 156982

Clethodim Schedonorus arundinaceus Tall Fescue POP POP ABND LOAEL 1 gs 0.18732 lb/acre 100 156982

Clethodim Schedonorus arundinaceus Tall Fescue POP POP ABND LOAEL 2 gs 0.18732 lb/acre 100 156982

Clethodim NR Poaceae Grass Family POP POP ABND NOAEL 1 gs 0.18732 lb/acre 100 156982

Clethodim NR Poaceae Grass Family POP POP ABND LOAEL 2 gs 0.18732 lb/acre 100 156982

Clethodim Medicago sativa Alfalfa POP POP BMAS NOAEL 90 d 0.19624 lb/acre 100 120431

Clethodim Schedonorus arundinaceus Tall Fescue POP POP COVR LOAEL 90 d 0.20516 lb/acre 100 156927

Clethodim Schedonorus arundinaceus Tall Fescue POP POP COVR LOAEL 74 d 0.20516 lb/acre 100 156927

Clethodim NR Poaceae Grass Family POP POP COVR NOAEL 517.48 d 0.20516 lb/acre 100 156927

Clethodim NR Poaceae Grass Family POP POP COVR NOAEL 517.48 d 0.20516 lb/acre 100 156927

Clethodim NR Plantae Plant Kingdom POP POP COVR NOAEL 517.48 d 0.20516 lb/acre 100 156927

Clethodim NR Plantae Plant Kingdom POP POP COVR NOAEL 517.48 d 0.20516 lb/acre 100 156927

Clethodim Stevia rebaudiana Candyleaf GRO MPH HGHT NOAEL 28 d 0.2136 lb/acre 100 157121

Clethodim Stevia rebaudiana Candyleaf PHY INJ DAMG NOAEL 56 d 0.2136 lb/acre 100 157121

Clethodim Stevia rebaudiana Candyleaf POP POP BMAS NOAEL 70 d 0.2136 lb/acre 100 157121

Clethodim NR Plantae Plant Kingdom POP POP ABND NOAEL 28 d 0.2136 lb/acre 100 157121

Clethodim NR Poaceae Grass Family POP POP ABND LOAEL 28 d 0.2136 lb/acre 100 157121

Clethodim NR Poaceae Grass Family PHY INJ DAMG NOAEL 49 d 0.2136 lb/acre 100 157121

Clethodim Solanum nigrum Black Nightshade PHY INJ DAMG NOAEL 49 d 0.2136 lb/acre 100 157121

Clethodim NR Plantae Plant Kingdom POP POP BMAS NOAEL 70 d 0.2136 lb/acre 100 157121

Clethodim Stevia rebaudiana Candyleaf GRO MPH HGHT NOAEL 28 d 0.2136 lb/acre 100 157121

Clethodim Stevia rebaudiana Candyleaf PHY INJ DAMG NOAEL 56 d 0.2136 lb/acre 100 157121

Clethodim Stevia rebaudiana Candyleaf POP POP BMAS NOAEL 70 d 0.2136 lb/acre 100 157121

Clethodim NR Poaceae Grass Family POP POP BMAS NOAEL 1460 d 0.21408 lb/acre 100 120528

Clethodim NR Poaceae Grass Family POP POP BMAS LOAEL 1460 d 0.21408 lb/acre 100 120528

Clethodim NR Poaceae Grass Family POP POP BMAS LOAEL 1460 d 0.21408 lb/acre 100 120528

Clethodim Panax quinquefolius American

Ginseng POP POP BMAS NOAEL 1460 d 0.21408 lb/acre 100 120528

Clethodim Panax quinquefolius American

Ginseng POP POP BMAS NOAEL 1460 d 0.21408 lb/acre 100 120528

## 133 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Panax quinquefolius American

Ginseng POP POP BMAS NOAEL 1460 d 0.21408 lb/acre 100 120528

Clethodim Solanum tuberosum Potato POP POP BMAS NOAEL hv 0.21408 lb/acre 100 82407

Clethodim Solanum tuberosum Potato POP POP BMAS NOAEL hv 0.21408 lb/acre 100 82407

Clethodim Alopecurus myosuroides Blackgrass GRO GRO WGHT ED50 20 d 0.23 L/ha 100 156760

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 7 d 0.2492 lb/acre 100 155807

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.2492 lb/acre 100 155807

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 7 d 0.2492 lb/acre 100 155807

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 102 d 0.2492 lb/acre 100 157103

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL hv 0.2492 lb/acre 100 157103

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL hv 0.2492 lb/acre 100 157103

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL hv 0.2492 lb/acre 100 157103

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL hv 0.2492 lb/acre 100 157103

Clethodim Medicago sativa Alfalfa POP POP BMAS NOAEL 50 d 0.24976 lb/acre 100 120431

Clethodim Medicago sativa Alfalfa POP POP BMAS NOAEL 45 d 0.24976 lb/acre 100 120431

Clethodim Medicago sativa Alfalfa POP POP BMAS NOAEL 40 d 0.24976 lb/acre 100 120431

Clethodim Medicago sativa Alfalfa POP POP BMAS NOAEL 50 d 0.24976 lb/acre 100 120431

Clethodim Medicago sativa Alfalfa POP POP BMAS NOAEL 45 d 0.24976 lb/acre 100 120431

Clethodim Medicago sativa Alfalfa POP POP BMAS NOAEL 40 d 0.24976 lb/acre 100 120431

Clethodim Digitaria sanguinalis Purple Crabgrass MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Sorghum arundinaceum Shattercane MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Sorghum arundinaceum Shattercane MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Sorghum arundinaceum Shattercane MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Sorghum arundinaceum Shattercane MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Sorghum arundinaceum Shattercane MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass MOR MOR MORT NR

- 28 d 0.24976 lb/acre 100 152884

## 134 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

LETH

Clethodim Sorghum arundinaceum Shattercane MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Sorghum arundinaceum Shattercane MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Sorghum arundinaceum Shattercane MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Digitaria sanguinalis Purple Crabgrass MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Sorghum arundinaceum Shattercane MOR MOR MORT NR

-

LETH 28 d 0.24976 lb/acre 100 152884

Clethodim Glyceria declinata Waxy

Mannagrass POP POP CNTL NOAEL 7 d 0.24976 lb/acre 100 96386

Clethodim Medicago polymorpha Burclover POP POP BMAS NOEL 80 d 0.24976 lb/acre 100 156904

Clethodim Medicago lupulina Black Medic POP POP BMAS NOEL 80 d 0.24976 lb/acre 100 156904

Clethodim Medicago truncatula Barrelclover POP POP BMAS NOEL 80 d 0.24976 lb/acre 100 156904

Clethodim Medicago polymorpha Burclover POP POP BMAS NOEL 79 d 0.24976 lb/acre 100 156904

Clethodim Medicago lupulina Black Medic POP POP BMAS NOEL 79 d 0.24976 lb/acre 100 156904

Clethodim Medicago truncatula Barrelclover POP POP BMAS NOEL 79 d 0.24976 lb/acre 100 156904

Clethodim Lamium amplexicaule Common Henbit POP POP ABND NOEL 79 d 0.24976 lb/acre 100 156904

Clethodim Medicago sp. Burclover POP POP ABND NOEL 79 d 0.24976 lb/acre 100 156904

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 91.32 d 0.24976 lb/acre 100 156971

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL hv 0.24976 lb/acre 100 156971

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL hv 0.24976 lb/acre 100 156971

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL d 0.24976 lb/acre 100 157020

Clethodim Gossypium hirsutum Cotton PHY INJ GINJ NOAEL 53 d 0.24976 lb/acre 100 157119

Clethodim Poa pratensis Kentucky

Bluegrass POP POP ABND NOAEL 56 d 0.24976 lb/acre 100 87931

Clethodim Poa pratensis Kentucky

Bluegrass POP POP ABND LOAEL 28 d 0.24976 lb/acre 100 87931

Clethodim Poa pratensis Kentucky

Bluegrass POP POP ABND LOAEL 28 d 0.24976 lb/acre 100 87931

Clethodim Poa pratensis Kentucky

Bluegrass POP POP ABND LOAEL 28 d 0.24976 lb/acre 100 87931

Clethodim Poa pratensis Kentucky POP POP ABND LOAEL 28 d 0.24976 lb/acre 100 87931

## 135 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Bluegrass

Clethodim Poa pratensis Kentucky

Bluegrass POP POP ABND LOAEL 28 d 0.24976 lb/acre 100 87931

Clethodim Poa pratensis Kentucky

Bluegrass POP POP ABND LOAEL 28 d 0.24976 lb/acre 100 87931

Clethodim Poa pratensis Kentucky

Bluegrass POP POP ABND LOAEL 56 d 0.24976 lb/acre 100 87931

Clethodim Bromus tectorum Downy Brome MOR MOR MORT LOAEL 47 d 0.24976 lb/acre 100 157092

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 60 d 0.25632 lb/acre 100 152009

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 60 d 0.25632 lb/acre 100 152009

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 60 d 0.25632 lb/acre 100 152009

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 60 d 0.25632 lb/acre 100 152009

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 60 d 0.25632 lb/acre 100 152009

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 60 d 0.25632 lb/acre 100 152009

Clethodim Cynodon dactylon Bermudagrass POP POP BMAS NOAEL LOAEL 1 gs 0.25632 lb/acre 24 156977

Clethodim Cynodon dactylon Bermudagrass POP POP BMAS LOAEL 1 gs 0.25632 lb/acre 24 156977

Clethodim Eremochloa ophiuroides Centipede Grass PHY INJ DAMG LOAEL 42 d 0.2676 lb/acre 100 154969

Clethodim Eremochloa ophiuroides Centipede Grass PHY INJ DAMG LOAEL 42 d 0.2676 lb/acre 100 154969

Clethodim Cynodon sp. Bermudagrass POP POP CNTL LOAEL 133 d 0.2676 lb/acre 100 156935

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 133 d 0.2676 lb/acre 100 156935

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 133 d 0.2676 lb/acre 100 156935

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL NOAEL 133 d 0.2676 lb/acre 100 156935

Clethodim Cynodon sp. Bermudagrass POP POP CNTL NOAEL 1 gs 0.2676 lb/acre 100 156935

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL NOAEL 1 gs 0.2676 lb/acre 100 156935

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 1 gs 0.2676 lb/acre 100 156935

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 1 gs 0.2676 lb/acre 100 156935

Clethodim Helianthus annuus Common Annual

Sunflower POP POP CNTL NOAEL hv 0.29904 lb/acre 100 152009

Clethodim Helianthus annuus Common Annual

Sunflower POP POP BMAS NOAEL hv 0.29904 lb/acre 100 152009

Clethodim Helianthus annuus Common Annual

Sunflower POP POP BMAS NOAEL hv 0.29904 lb/acre 100 152009

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.29904 lb/acre 100 152009

Clethodim Glycine max Soybean POP POP BMAS NOAEL hv 0.29904 lb/acre 100 152009

Clethodim Helianthus annuus Common Annual

Sunflower POP POP BMAS NOAEL hv 0.29904 lb/acre 100 152009

Clethodim Helianthus sp. Sunflower POP POP BMAS NOAEL hv 0.29904 lb/acre 24 156977

Clethodim Helianthus sp. Sunflower POP POP BMAS NOAEL hv 0.29904 lb/acre 24 156977

Clethodim Alopecurus myosuroides Blackgrass GRO GRO WGHT ED50 20 d 0.3 L/ha 100 156760

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 14 d 0.3115 lb/acre 100 66802

## 136 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 42 d 0.3115 lb/acre 100 66802

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 70 d 0.3115 lb/acre 100 66802

Clethodim Hibiscus cannabinus Deccan Hemp POP POP BMAS NOAEL d 0.3738 lb/acre 100 156934

Clethodim Hibiscus cannabinus Deccan Hemp GRO GRO HGHT NOAEL d 0.3738 lb/acre 100 156934

Clethodim Solanum tuberosum Potato POP POP BMAS NOAEL hv 0.4014 lb/acre 100 82407

Clethodim Plankton sp. Plankton POP POP PSYN NOAEL 1 d 0.43 AI kg/ha 100 53095

Clethodim Carex appressa Tall Sedge POP POP COVR NOAEL 329 d 0.446 lb/acre 100 157039

Clethodim Sorghum halepense Johnson Grass GRO MPH LGTH ED50 5 d 0.4625 ppm 100 156992

Clethodim Cynodon dactylon Bermudagrass BCM BCM PRCO NOAEL 365 d 0.49952 lb/acre 100 156888

Clethodim Cynodon dactylon Bermudagrass POP POP BMAS LOAEL 365 d 0.49952 lb/acre 100 156888

Clethodim Cynodon dactylon Bermudagrass POP POP BMAS LOAEL 365 d 0.49952 lb/acre 100 156888

Clethodim Cynodon dactylon Bermudagrass BCM BCM PRCO LOAEL 365 d 0.49952 lb/acre 100 156888

Clethodim Eremochloa ophiuroides Centipede Grass PHY INJ DAMG NOAEL 84 d 0.5352 lb/acre 100 154969

Clethodim Sorghum halepense Johnson Grass GRO GRO WGHT EC50 21 d 0.54201 lb/acre 100 156993

Clethodim Aegilops triuncialis Barbed

Goatgrass POP POP ABND LOAEL d 0.55304 lb/acre 100 156883

Clethodim NR Magnoliophyta Angiosperm

Division POP POP ABND LOAEL d 0.55304 lb/acre 100 156883

Clethodim Holocarpha virgata Yellowflower

Tarweed POP POP COVR LOAEL d 0.55304 lb/acre 100 156883

Clethodim Navarretia jepsonii Jepson's

Pincushionplant POP POP COVR NOAEL d 0.55304 lb/acre 100 156883

Clethodim Poa secunda Sandberg'S

Bluegrass POP POP COVR NOAEL d 0.55304 lb/acre 100 156883

Clethodim Bromus hordeaceus Soft Chessgrass POP POP COVR NOAEL d 0.55304 lb/acre 100 156883

Clethodim Sorghum halepense Johnson Grass POP POP CNTL LOAEL 30 d 0.7359 lb/acre 100 70779

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 30 d 0.7359 lb/acre 100 70779

Clethodim Aloysia polystachya Te de Burro

Shrub PHY INJ GINJ NOAEL 30 d 0.7359 lb/acre 100 70779

Clethodim Aloysia polystachya Te de Burro

Shrub POP POP BMAS NOAEL hv 0.7359 lb/acre 100 70779

Clethodim Amelichloa brachychaeta Puna Needle

Grass POP POP CNTL LOAEL 30 d 0.7359 lb/acre 100 70779

Clethodim Bromus tectorum Downy Brome MOR MOR MORT NR

-

LETH 47 d 0.99904 lb/acre 100 157092

Clethodim Sorghum halepense Johnson Grass GRO GRO GGRO EC50 0.25 d 16.4 uM 100 156994

Clethodim Sorghum halepense Johnson Grass REP REP GERM EC50 0.125 d 25.8 uM 100 156994

Clethodim Elymus repens Quackgrass POP POP WGHT LOAEL 1 gs 240000 ppm 100 156921

Clethodim Elymus repens Quackgrass POP POP WGHT LOAEL 1 gs 240000 ppm 100 156921

Clethodim Elymus repens Quackgrass POP POP WGHT LOAEL 1 gs 240000 ppm 100 156921

## 137 Chemical

Name Genus Species Common Name Effect

Group Effect Meas Endpt1 Endpt2 Dur

Preferred

Mean Dur Unit

Preferred Conc #1

Purity

Adjusted in

Preferred

Unit Mean Conc Units

Preferred %

Purity Ref #

Clethodim Elymus repens Quackgrass POP POP WGHT LOAEL 1 gs 240000 ppm 100 156921

Clethodim Elymus repens Quackgrass POP POP WGHT LOAEL 1 gs 240000 ppm 100 156921

Clethodim Elymus repens Quackgrass POP POP WGHT LOAEL 1 gs 240000 ppm 100 156921

Clethodim Elymus repens Quackgrass POP POP WGHT LOAEL 1 gs 240000 ppm 100 156921

Clethodim Elymus repens Quackgrass POP POP WGHT LOAEL 1 gs 240000 ppm 100 156921

Clethodim Elymus repens Quackgrass POP POP WGHT LOAEL 1 gs 240000 ppm 100 156921

Clethodim Elymus repens Quackgrass POP POP WGHT LOAEL 1 gs 240000 ppm 100 156921

Clethodim Elymus repens Quackgrass POP POP WGHT LOAEL 1 gs 240000 ppm 100 156921

Clethodim Elymus repens Quackgrass POP POP WGHT LOAEL 1 gs 240000 ppm 100 156921

Clethodim Panicum repens Torpedo Grass POP POP COVR LOAEL 42 d lb/acre 100 154969

Clethodim Panicum repens Torpedo Grass POP POP COVR LOAEL 42 d lb/acre 100 154969

Clethodim Panicum repens Torpedo Grass POP POP COVR LOAEL 42 d lb/acre 100 154969

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL 91.32 d lb/acre 100 156971

Clethodim Arachis hypogaea Peanut POP POP BMAS NOAEL hv lb/acre 100 156971

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL d lb/acre 100 157020

Clethodim Cynodon dactylon Bermudagrass POP POP CNTL LOAEL d lb/acre 100 157020