3+<E0
UNITED STATES ENVIRONMENTAL PROTECTIONAGENCY WASHINGTON D.C., 20460

OFFICE OF PREVENTION, PESTICIDESAND TOXIC SUBSTANCES

PC Code: 000692 DP Barcodes: 332763,332767 Date: April 12,2007

MEMORANDUM

SUBJECT: Environmental Fate and Ecological Risk Assessment in Support of the Section 3 Registrationof the New Chemical Pyrasulfotole (Bayer 309).

TO: Tracy White, ChemicalReview Manager Joanne Miller, Risk Manager Registration Division (7505P) 

### y- ,2-67 FROM: Melissa A. Panger,Ph.D., Biologist ( L' ' * Marietta Echeverria, Environmental 

## &- 

## 4 //2/0

. 7. EnvironmentalRisk Branch 

### IV



# . \ Megan Thynge,Environmental Protection Specialist 

# 1 C t \ Environmental Information and Support Branch 

# I

' I Environmental Fate and Effects Division (7507P)

REVIEWED
!?-- , d cT 

### tT

-, BY: Thomas M. Steeger, Ph.D., Senior Biologist 

# Ifi /,L/2 bl4 &, R. David Jones, Ph.D., SeniorAgronomist

## /: 

## dH,
EnvironmentalRisk Branch IV Environmental Fate and Effects Division (7507C)

-7 APPROVED 1, BY: ElizabethBehl, Branch Chief 1 

# \p 

# uk - 

# 17

# -c17

. / EnvironmentalRisk Branch 

### IV Environmental Fate and Effects Division (7507P)

TheEnvironmental Fate and Effects Division (EFED)has completed the draft environmental fate and ecologicalrisk assessmentin support ofthe Section 3 registration decision on the new herbicide pyrasulfotole (Bayer 309). The results of this screening-levelrisk assessment indicate that the proposed uses of pyrasulfotole at a maximum application rate of 0.045 lb a.i./acrehave the potential for direct adverse effects for terrestrial and semi-aquatic dicotyledonousplants, some small mammals less than 35 g (chronic exposure), and listed freshwatervascular plants. Regarding listed species,EFED's screeninglevel analysis shows the possibility of direct effects to listed aquatic vascular plants, terrestrial and semi-aquatic dicotyledonous plants, and mammals(chronic exposure). RQs arereduced to below Agency LOCs for listed aquatic vascular plants and mammals (listed and non-listed)with application rates of 10.030 lb a.i./acreand L 0.023 lb a.i./acre, respectively, indicating directrisks to these taxa would not be expected at these application rates. At this time, no Federally-listedtaxa can be excluded from the potential for direct andlor indirect effects from the proposed uses of pyrasulfotole, since there is a potential for indirect effects to taxa that might rely on plants (even at a maximum application rate of 0.023lb a.i./acre) andlor mammals for some stage of their life-cycle. Based on LOCATES, there is the potential for a total of 390 listed species to be directly affectedby the proposed uses of pyrasulfotole, while 427 speciesmay be indirectly affectedby the use of the chemical. Details regarding the environmental fate, ecological effects and ecological risks associated with the current uses of pyrasulfotole can be found in the executive summary of the attached document.

Data Gaps

Table A.1. identifies the status of environmental fate and transport study requirements and Table A.2. identifies the status of ecological effects study requirements. The available environmental fate and transport data for pyrasulfotole are considered complete and are adequate for risk assessment purposes.

Most of the ecological effects data gaps result fromuncertainties surrounding potential ecological risks associated with the chronic effects of pyrasulfotole in estuarinelmarine invertebrates. Estuarinetmarineinvertebrates (i.e., mysids) are at least 100times more sensitive to pyrasulfotole on an acute exposure basis than all of the other aquatic animals tested and pyrasulfotole is persistent, however, no chronic data are available for this taxon. Risks to estuarinelmarine invertebrates are not expected with the current proposed use on cereal grains, in part because the use sites associated with cereal grains are largely outside of estuarinetmarine environments. However, if the uses for pyrasulfotole are expanded beyond cereal grains, the potential risk to estuarinelmarine invertebrates will need to be re-assessed. Therefore, we recommend that the toxicity studies for estuarinetmarineanimalsbe held 'InReserve' at this time.
Additionally, because pyrasulfotole is persistent and has the potential to progressively bind to certain soils through time as it degrades and forms unextractable residues, there is the potential for pyrasulfotole (or residues of concern) to accumulate in the benthos at levels that could result in toxic exposure to benthic and epibenthic aquatic organisms, especially those that consume soil. The potential risk to benthic and epibenthic organisms could not be assessed here, however, because a lack of available toxicity data for these taxa. Due to the lack of data and the potential for adverse effects, we recommend that acute and chronic toxicity data on benthic animals be requestedby the registrant.

Labeling Recommendations
According to the Label Review Manual, the followinglabel statements are recommended:

Environmental Hazards

"Do not apply directly to water, or to areas where surface water is present or to intertidal

areas below the mean high water mark. Do not contaminate water when disposing of equipment washwater or rinsate."Ground Water Advisory
"Pyrasulfotole is known to leach through soil into ground water under certain conditions

as a result of label use. Use of this chemical in areas where soils are permeable, particularly where the water table is shallow, may result in ground-water contamination."
Surface Water Label Advisories

"This product may contaminate water through drift of spray in wind. This product has a high potential for runoff for several months or more after application after application. Poorly draining soils and soils with shallow water tables are more prone to produce runoff that contains this product. A level, well maintained vegetative buffer strip between

areas to which this product is applied and surface water features such as ponds, streams, and springs will reduce the potential for contamination of water from rainfall-runoff. Runoff of this product will be reduced by avoiding applications when rainfall is forecasted to occur within 48 hours."ARE DATA ADEQUATE

FOR RISK ASSESSMENT? Yes 

### TableA. 1. 

### Ecological Fate Studies for Pyrasulfotole. COMMENTS GUIDE-

LINE

Acceptable MRID

46801705 None [Pyrazole-3-14C] AE03 17309: hydrolytic 

### I degradation I 161-2 

## 1 46801706 

## 1 ['4~-~~-~henyl] and 

## I Acceptable STUDY TITLE

Yes EPACLASSIFICATION

None [14~-3-pyrazole] AE03 17309: phototransformation in 

### I water 161-3 

## 1 46801707 

## 1 [~yrazole-3-I4C] 

## I Acceptable Yes None AE03 17309: phototransformation on soil [~henyl-~-'~c]- and [pyrazole-3-14~]-~ 03 17309: aerobic soil metabolism in a loamy sand soil of US origin under laboratory Acceptable Yes None

Yes 162-1 None

0317309: aerobic soil metabolism in a silt loam soil of US origin under laboratory 4680 1710



## I conditions at 25°C 162-1 

### 1 4680171 1 

### 1 [~hen~l-UL-'~~] and 

## I Supplemental The study was conducted on a foreign soil; upgradeable conditions at 25OC [~henyl-U-'~C]- and

Yes Acceptable

0317309: aerobic soil metabolism in a 

## I European soil 162-2 

### 1 46801712 ] [Phenyl-U~-'~~l and 

### I Accevtable Yes

Yes None 

## I 1 0317309: anaerobic soil 

## I

None 162-3 

### I I 03 17309: anaerobic 

### 1 4680 1714

Yes 162-3 None metabolism [P~~~~~-UL-'~C]AE



## 1 1 0317309: anaerobic 

## I Acceptable

4680 1715 

### I aquatic metabolism 162-4 

## 1 468017 13 

## 1 [Pyraz01-3-'~~]~~ ( Acceptable Yes aquatic metabolism [~yrazole-3-'~C]AE

None Acceptable

0317309 and [phenylUL-I~CIAE 0317309: aerobic aquatic 

### I metabolism 163-1 

## 1 4680 1703 

## 1 Adsorption/desorption 

### I Acceptable Yes None of AE 03 17309 on five soils and one sediment

### I GUIDE- 

### I MRID 

### I STUDY TITLE



## I in five soils 164- 1 

### 1 46801 716 

### 1 Terrestrial field



## 1 2004 164- 1 

## 1 46801717 

### 1 Terrestrial field 

# I I

dissipation of AE 03 17309 in North Dakota soil, 2004 Terrestrial field dissipation of AE 0317309 in Washington soil. 2004 dissipation ofAE 03 17309 in Kansas soil, Acceptable Yes EPACLASSIFICATION

Acceptable

Acceptable 

# Y ARE DATA ADEQUATE

FOR RISK ASSESSMENT? Yes

Table A.2. Ecological Effects Studies for Pyrasulfotole. GUIDE- 

### I MRID 

### I STUDY TITLE 

### 1 EPACLASSIFICATION



### ( Bobwhite
I 71-2 

### 1 468017-3 1 

### 1 Technical AE03 17309: 

### 1 Acceptable 1 71-1

71-2



## I I A Subacute Dietary 

## I 46801 7-29

4680 17-30



### I 1 03 17309onNorthern 

### I 71-4 Technical AE03 17309: An Acute Oral LDsO with Northern Bobwhite. Technical AE03 17309: A Subacute Dietary with Northern Acceptable

Acceptable

468017-32

71-4

Acceptable 4680 17-24

468017-25 Acceptable LCSo with ~allards Effect of Technical AE

468017-33 03 17309 on Mallard Reproduction. The 96 Hour Acute Toxicity to the Rainbow Trout, Oncorhynchus mykiss, in a Static System; AE 03 17309 Technical 97.4%wlw (Amended Report). The 96 Hour Acute Toxicity to the Bluegill Sunfish,Lepomis macrochirus, in a Static System, AE 0317309 ARE DATA 

## 1 ADEQUATE 

### 1 FORRISK

ASSESSMENT?

Acceptable Yes

Bobwhite Reproduction Effect of Technical AE Yes

Acceptable I Yes

Yes

Yes

Yes

Yes COMMENTS 

# 7

NoneCOMMENTS

None

None

None

None

None

None

No negative control was tested

None

None

None ARE DATA ADEQUATE

FOR RISK ASSESSMENT?

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes EPACLASSIFICATION

Acceptable

Acceptable

Acceptable

Acceptable

Acceptable

Acceptable

Supplemental

Acceptable

Acceptable

Acceptable STUDY TITLE

Technical, 98.2% w/w (Amended Report) The 48-Hour Acute Toxicity to the Water Flea, Daphnia magna, in a Static System AE 0317309 Technical 97.4%w/w AE 03 17309-Acute Toxicity to Eastern Oysters (Crassostrea virginica) Under FlowThrough Conditions AE 03 17309- Acute Toxicity to Mysids (Americamysis bahia) Under Static Conditions Acute Toxicity of AE 03 17309 Technical to the Sheepshead Minnow (Cyprinodon variegates) Under Static Conditions. Chronic Toxicity ofAE 03 17309 Technical to the Daphnia magna Under Static Renewal Conditions. Early Life Stage Toxicity of AE 0317309 Technical to the Fathead Minnow (Primephalespromelas) Under Flow-Through Conditions Contact toxicity (LD50) to honey bees (Apis mellifera L.), Substance technical Toxicity ofAE 03 17309 Technical to Duckweed (Lemna gibba G3) Under Static Conditions. Toxicity of AE 03 17309 Technical to the Freshwater Diatom Naviculapelliculosa Toxicity of AE 03 17309 Technical to the Green AlgaGUIDELINE

72-2

72-3

72-3

72-3

72-4

72-4

141-1

850.4400

850.5400

850.5400 MRID

4680 17-21

4680 17-22

468017-23

46801 7-26

468017-27

468017-28

468017-35

468017-36

468017-38

468017-37COMMENTS

A NOAEC for biomass could not be determined due to significant inhibition
at all treatment levels None

None

None

ECZ5 values could not be determined for onion and sugarbeet survival, and the reviewer was unable to statistically analyze plant height because the study authors onlyreported the range of values within each replicate and the treatment
mean; no replicate mean values were reported. A NOAEC could not be determined for the most sensitive endpoint, cucumber dry weight. Inhibition in biomass at the lowest treatment level was 18%.GUIDELINE

850.5400

850.5400

123-la

123-la

123-1 b

123-1 b EPACLASSIFICATION

Supplemental

Acceptable

Acceptable

Acceptable

Supplemental

Supplemental AREDATA ADEQUATE

FOR RISK ASSESSMENT?

Yes

Yes

Yes

Yes

Yes

Yes MRID

468017-39

468017-40

46801 9-26

468019-36

468019-27

468019-37 STUDY TITLE

Pseudokirchneriella subcapitata (a.k.a. Selenastrum capricornutum). Toxicity of AE 0317309 Technical to the Blue-Green Algae Anabaenajlos-aquaea

Toxicity of AE 03 17309 Technical to the Saltwater Diatom Skeletonema costatum. Non-target terrestrial plants: Seedling emergence and growth test (Tier 2) Suspoemulsion: 50+ 12.5g/L (Code: AE 0317309 02 SE06 A102) Non-target terrestrial plants: Seedling emergence and seedling growth test (Tier 2); AE 0.317309+Mefenpyr diethyl+Bromoxynil (Code: AE 03 17309 03 EC23 A8) Non-target terrestrial plants: Vegetative vigor test (Tier 2) AE 03 17309 + Mefenpyr di-ethyl (AE F107892); Suspo-emulsion: 50+ 12.5 g/L (Code: AE 03 17309 02 SE06 A102)

Non-target terrestrial plants: Vegetative Vigor test (Tier 2), AE 03 17309+Mefenpyr diethyl+Bromoxynil (Code: AE 03 17309 03 EC23 A8)GUIDELINE

850.6200

850.6200

NonGuideline

NonGuideline EPACLASSIFICATION

Supplemental

Supplemental

Supplemental

Supplemental MRID

46801 7-41

468017-42

46801 7-43

468017-34 STUDY TITLE

AE 0317309, substance,technical (Code: AE 031730900 1C96000 1): Acute Toxicity to Earthworms (Eiseniafetida) tested in Artificial Soil RF'A 203328,Acute Toxicity (14-Day)to Earthworms (Eisenia foetida) Isoxaflutole-RPA 203328 (AE B197555): Reproduction toxicity to the earthworm Eisenia fetida in artificial soil

Oral toxicity (LD50) to honey bees (Apis mellifera L.), Substance technical ARE DATA ADEQUATE

FOR RISK ASSESSMENT? Yes

Yes

Yes

Yes COMMENTS

Non-guideline (EPA requires a 28-day test, this is a 14-day test)

Non-guideline (EPA requires a 28-day test, this is a 14-day test) Non-guideline - This study was based on procedures ofthe IS0 Guideline 11268-2 "Soil quality-Effects of pollutants on earthworms (Eisenia fetida) Part 2: Determinationof effects on reproduction" (July 1998). Non-guideline

## Environmental Fate and Ecological Risk Assessment for the Registration ofthe New Chemical Pyrasulfotole 

## (AE 0317309)

Pyrasulfotole (5-hydroxy-1,3-dimethyl- 1 

### H-pyrazol-4-yl)[2-(methylsulfony1)-4- (trifluoromethyl)phenyl]methanone CAS 

### NO. 365400-1 1-9



### Prepared by:



### Melissa Panger, Ph. D.' 

### U. S. Environmental Protection Agency Marietta Echeverrial Office ofPesticide Programs Megan Thynge -/2 - ~3 

## 7 EnvironmentalFate and Effects Division Reviewed by: c 

### 'EnvironmentalRisk Branch IV Thomas M. Steeger, P~.D.' 2

### Environmental Information Services Branch

-, 

### R. David Jones, P~.D.' 1200Pennsylvania Ave., NW Mail Code 7507P Washington, DC 20460

## Environmental Fate and Ecological Risk Assessment for the Registration of the New Chemical Pyrasulfotole (AE 

## 0317309)

Pyrasulfotole (5-hydroxy- 1,3-dimethyl-1 

### H-pyrazol-4-yl)[2-(methylsulfony1)-4- (trifluoromethyl)phenyl]methanone 

### CAS NO. 365400-1 1-9

Prepared by:



### Melissa Panger, Ph. D.' Marietta ~cheverria' Megan ~h~n~e' Reviewed by: 

### Thomas

### M. Steeger,

### P~.D.' R. 

### David Jones, P~.D.' U. S. 

### Environmental Protection Agency Office ofPesticide Programs Environmental Fate and Effects Division 1 

### Environmental Risk Branch 

### IV '~nvironmental Information ServicesBranch
1200 Pennsylvania Ave., NW Mail Code 7507P Washington,DC 20460TABLE OFCONTENTS

I



# . EXECUTIVE SUMMARY



### .......................................................................................... 5 A



# . Nature of Chemical Stressor



### .................................................................... 5 B


# . Conclusions 

## - Exposure Characterization



### ............................................... 5 C



# . Conclusions 

### - Effects Characterization



### ................................................... 5 D


# . Potential Risks to Non-target Organisms



### ................................................ 6 

### E



# . Uncertainties and Data Gaps



### .................................................................... 8 I1 PROBLEM FORMULATION



### .................................................................................. 10 A



# . Stressor Source and Distribution



### ........................................................... 10 

### 1



# . Source and Intensity



### ................................................................... 10 

### 2



# . PhysicaVChemicaVFate and Transport Properties



### ..................10 

### 3



# . Pesticide Type, Class, and Mode of Action



### ............................... 11 4



# . Overview of Pesticide Usage



### ....................................................... 11 B



# . Receptors



### ................................................................................................. 11



### ................................................. 1



# . Aquatic and Terrestrial Effects 11 

### 2



# . Ecosystems at Risk



### ...................................................................... 12 C



# . Assessment Endpoints



### ............................................................................. 12 D



# . ConceptualModel



### ................................................................................... 14 1



# . Risk Hypotheses



### .......................................................................... 14 2



# . Diagram



### ........................................................................................ 14 E



# . Analysis Plan



### ............................................................................................16 1



# . Preliminary Identification of Data Gaps and Methods



### ...........17 2



# . Measures to Evaluate Risk Hypotheses and Conceptual Model



### ....................................................................................................... 17



### ..................................................... a

# . Measures of Exposure 17



### ........................................................... b



# . Measures of Effect 18 111



# . ANALYSIS



### ........................................................................................................... 19



### ............................................................................... A



# . Use Characterization 19



### ..................................................................... B



# . Exposure Characterization 19



### ............ 1



# . Environmental Fate and Transport Characterization 23

a

# . Degradation



### ..................................................... 24



### ....................................... b



# . Mobility and Transport 25

c

# . Field Studies



### ..................................................... 25 d



# . Degradates



### ...................................................... 25 2



# . Measures of Aquatic Exposure



### .................................................. 27

a

# . Aquatic Exposure Modeling



### ........................................... 27 b



# . Aquatic Exposure Monitoring and Field Data



### .............31 3



# . Measures of Terrestrial Exposure



### ............................................. 31

a

# . Terrestrial Exposure Modeling



### ................................31 C



# . Ecological Effects Characterization



### ......................................................... 32 1


# . Aquatic Effects Characterization



### .................................................. 35

a

# . Aquatic Animals



### .................................................................. 35 b



# . Aquatic Plants



### .................................................................... 36 2



# . Terrestrial Effects Characterization



### .............................................36

a

# . Terrestrial Animals



### ............................................................. 36

# . ................................................................ b Terrestrial Plants 38



### ............... 3



# . Toxicity of the Degradate Pyrasulfotole-Benzoic Acid 36 IV



## . Risk Characterization



### .......................................................................................... 40



### ................. A



# . Risk Estimation



### . Integration of Exposure and Effects Data 40 1



# . Non-target Aquatic Animals and Plants



### ....................................... 42



### ..................................................... 2



# . Non-target Terrestrial Animals 43 3



# . Non-target Terrestrial and Semi-aquatic Plants



### ..........................44 B



# . Risk Description



### .......................................................................................... 45



### ........................................................ 1



# . Risks to Aquatic Organisms 46

a

# . Animals



### ............................................................................. 46 b



# . Plants



### ................................................................................ 47 2



# . Risks to Terrestrial Organisms



### ................................................... 48

a

# . Animals



### ............................................................................. 48 b



# . Plants



### ................................................................................ 49 3



# . Review of Incident Data



### .................................................................. 51 4



# . Federally Threatened and Endangered (Listed) Species Concerns



### ....................................................................................................... 51

a

# . Action Area



### ................................................................. 5 1 b



# . Taxonomic Groups Potentially at Risk



### .......................... 52 (1)



# . Discussion of Risk Quotients



### ............................. 52



### .................. (2)



# . Probit Dose Response Relationship 52 (3)



# . Indirect Effects Analysis



### ..................................... 54 (4)



# . Critical Habitat



### .................................................... 55



### ...................................... (5)



# . Co-occurrence Analysis 56 C



# . Description of Assumptions, Limitations. Uncertainties. Strengths and Data Gaps



### ......................................................................................... 59 V



# . References



### ................................................................................... 60

LIST OFFIGURES: FIGURE 1: Conceptual Plan Diagram Depicting Sources of Exposure. Potential Receptors and Adverse Effects from the Proposed Uses of Pyrasulfotole



### .........16 FIGURE 2



# . Acres of Barley Grown By County in the United Stated in 2005 (based

on information from USDA.NASS)



### ........................................................ 20 FIGURE 3



# . Acres of Wheat Grown By County in the United Stated in 2005 (based on information fromUSDA-NASS)



### ........................................................ 21 FIGURE 4



# . Acres of Oats Grown By County in the United Stated in 2005 (based on information from USDA.NASS)



### ............................................................ 22

LIST OFTABLES: TABLE 1

. Listed Species Risks Associated with Potential Direct or Indirect Effects



### ............... Due to the Proposed Applications of Pyrasulfotole on Cereal Grains 8 TABLE 2



# . Taxonomic Groups and Test SpeciesEvaluated for Ecological Effects in

. Screening-Level Risk Assessments



### ......................................................... 12 TABLE 3



# . Acute and ChronicMeasures ofEffect



### .......................................... 19 TABLE 4



# . Application Information from the Proposed Pyrasulfotole Labels



### ........ 23TABLE 5



# . Summary of Environmental Chemistry. Fate and Transport Properties of Pyrasulfotole



### ................................................................................. 24



### ....... TABLE 6



# . Summary of Crop Scenarios Used in Aquatic Exposure Modeling 28 TABLE 7



# .PRZMIEXAMS Input Parameters for Aerial Application of Pyrasulfotole to Cereal Grains



### .............................................................................. -30 Table 8



# . Tier I1 SurfaceWater 1-in-10-Year Estimated Environmental Concentrations (EECs) of Pyrasulfotole from Cereal Grain Use (ppb)



### ............ 31 TABLE 9



# . EECs on Potential Food Items Following Label-Specified Applications of Pyrasulfotole Using the T-REX Model (ppm)



### ........................................... 32 TABLE 10



# . EECs on Plants Following Label-Specified Applications of Pyrasulfotole Using the TerrPlant Model (Ibs a.i./A).



### .................................. 32 TABLE 11



# .Summary of Specific Assessment Endpoints for Animals and Plants



### .............................................................. Considered in this Assessment 33 TABLE 12



# . Terrestrial Monocot and Dicot Endpoints (Ibs a.i./acre) from the Pyrasulfotole Seedling Emergence and Vegetative Vigor Studies



### ................... 39 TABLE 13



# . RPA 203328 Acute Toxicity Data for aVariety of Animals and Plants



### ............................................................................................. 40 TABLE 14



# . Agency Levels of Concern (LOC)



### .............................................. 42 TABLE 15



# . Aquatic Animal RQ Values for Exposure to Pyrasulfotole



### ................ 43 TABLE 16



# . Aquatic Plant RQ Values for Exposure to Pyrasulfotole



### .................. 43 TABLE 17



# . Avian RQ Values for Chronic Exposure to Pyrasulfotole



### .................43 TABLE 18



# . Mammalian RQ Values for Chronic Exposure to Pyrasulfotole



### .........44 TABLE 19



# . RQ Values for Terrestrial and Semi-Aquatic Plants Exposed to



### .................................................................................... Pyrasulfotole 45 TABLE 20



# . Comparison of RQValues for Terrestrial and Semi-Aquatic Dicots Exposed to the AE 0317309 SE06 and AE 0317309

## +Bromo formulations



### ....... 50 TABLE 21



# . Chance of an Individual Effect Corresponding to the Listed Species Acute LOCs Using a Probit Slope Response Relationship



### ............................ 54 TABLE 22



### . Listed Species Risks Associated with Potential Direct or Indirect Effects Due to the Proposed Applications of Pyrasulfotole on Cereal Grains



### .... 55 TABLE 23



# . Tabulation by State and Taxonomic Group of Listed Speciesthat Occur in Counties with Potential Pyrasulfotole Use Sites



### ............................ 58

LIST OFAPPENDICES: APPENDIX A: ECOTOX Results



### ............................................................. 68



### ...................... APPENDIX B: Environmental Fate and Transport Study Details 69 APPENDIX C: PRZMIEXAMS Output Data from the ND Wheat, ORWheat, and TX Wheat Scenarios



### ..................................................................... 80 APPENDIX D: Input Parameters and Results fromT-REX



### ............................. 86 APPENDIX E: TerrPlant Model



### ............................................................... 89 APPENDIX F: Results from Submitted Eco Toxicity Studies for Pyrasulfotole



### ..... 91



### ............................................ APPENDIX G: Input Parameters forAgDRIFT 95 APPENDIX H: Federally Listed Speciesthat Co-Occur with Potential Pyrasulfotol Use Sites atthe County-Level (Based on LOCATES)



### ................................ 102

### I. EXECUTIVE 

### SUMMARY

A. Nature of Chemical Stressor
Pyrasulfotole is a new herbicide that is proposed for registration by the registrant Bayer Cropscience for use on wheat, barley, oats and triticale. Pyrasulfotole is a systemic herbicide that inhibits the enzyme 4-hydroxyphenylpyruvate dioxygenase (4-HPPD) and

causesbleaching symptoms, necrosis, and ultimately death in susceptible plants. The two pyrasulfotole (AE 0317309) end-use products being proposed for registration are AE 03 17309

### + Bromo Herbicide (an emulsifiable concentrate with 3.3% pyrasulfotole, 13.4% bromoxynil octanoate, and 12.9% bromoxynil heptanoate) and AE 0317309 SE06 Herbicide [a suspo-emulsion (consisting of suspension concentrates and oil-in-water emulsions) containing 4.4% pyrasulfotole]. Pyrasulfotole would be applied as apostemergent foliar spray once a year via ground, aerial, or sprinkler irrigation at a maximum rate of 0.045 lb a.i./acre according to the proposed label.



### B. Conclusions 

### - Exposure Characterization
Pyrasulfotole is highly soluble in water, has a low vapor pressure and low octonal-water partitioning coefficient. Therefore, volatilization from water and soil surfaces is not expected to be an important route of environmental dissipation and bioaccumulation is unlikely. Pyrasulfotole is stable to hydrolysis and photolysis and moderately susceptible to microbial degradation under aerobic conditions in soils. Pyrasulfotole is expected to be persistent under certain conditions and moderately mobile to mobile (FA0 classification) in the environment. Major routes of dissipation include microbial degradation in soils, formation ofunextractable residues in soils and sediments, and dilution. Depending on soil, site and meteorological conditions pyrasulfotole may be transported off-site via runoff, leaching and spray drift. There was one major degradate, pyrasulfotole-benzoic acid (RPA 203328, AE B197555), detected in the aerobic soil metabolism and terrestrial field dissipation studies. Based on available ecological effects data, exposure to pyrasulfotole-benzoic acid is not ofrisk concern, and, therefore, it is not assessed here.

C. Conclusions 

### - Effects Characterization
Pyrasulfotole is classified as practically nontoxic to fish and freshwater invertebrates, slightly toxic to freshwater nonvascular plants, moderately toxic to marine nonvascular plants, highly toxic to estuarinelmarine invertebrates, and very highly toxic to aquatic vascular plants on an acute exposure basis. A freshwater fish early life-cycle reproductive study on fathead minnows resulted in a NOAEC of 0.58 mg a.i./L based on

a reduction in total length. A chronic test for Daphnia resulted in a NOAEC of 12.8mg a.i./L, based on themost sensitive endpoint, survival.
Pyrasulfotole is classified as practically nontoxic to avian species on an acute oral basis and is practically nontoxic to slightly toxic to avian species on a subacute dietaryexposurebasis. The lowest NOAEC in an avian reproduction study was for the mallardduck (167 mg a.i./kg diet), based on reduced male weight gain. Pyrasulfotole is classified as practically nontoxic to mammals on an acute oral basis. A two generation reproduction study on rats resulted in a NOAEL of 2.5 mag-bwldaybased on delayed maturation and corneal opacity. Pyrasulfotole is classified as 'practically nontoxic' to non-target terrestrial insects.

Results ofthe Tier 

### I1 seedling emergence studies with the AE 03 1730902 SE06 and AE 0317309

### +Bromo formulations showed no measurable effects to monocots at any ofthe tested treatment levels. For dicots, the 

### AE 03 17309

## + Bromo formulation is more toxic than the AE 03 17309 02 SE06 formulation, however, because it is a mixture of different active ingredients, the results from the studies using this formulation cannot be used to specifically assess the risks ofpyrasulfotole to plants. Therefore, the results from the AE 03 1730902 SE06 study (i.e., a NOAEC of 0.00039 lb a.i./A and an EC25 of 0.0011 lb a.i./A based on tomato dry weight) are used to assess the effects of exposure to pyrasulfotole on seedling emergence in non-listed and listed dicots.

Results ofthe Tier I1 vegetative vigor studies identify onion as the most sensitive monocot with decreased dry weight as the most sensitive endpoint affected (with the AE 03 17309 02 SE06 formulation). The NOAEC and EC25values for onion dry weight were 0.0125 lbs a.i./A and 0.017 lbs a.i./A, respectively. No effects were seen in monocots in the vegetative vigor study with the AE 03 17309

## + Bromo formulation. For dicots, although the AE 0317309

## + Bromo formulation (with a mixture of a.i.'s) is more toxic than the AE 03 17309 02 SE06 formulation, the results from the SE06 formulation (i.e., a NOAEC of 0.0.000797 lb a.i./A and an EC25 of 0.00081 lb a.i./A, based on tomato dry weight) areused to assess the effects of exposure to pyrasulfotole on vegetative vigor in non-listed and listed terrestrial dicots.

D. Potential Risks to Non-target Organisms

The results ofthis screening-level risk assessment indicate that the proposed uses of pyrasulfotole have thepotential for direct adverse effects for terrestrial and semi-aquatic dicotyledonous plants, some small mammals less than 35 g (chronic exposure), and listedfreshwater vascular plants. Risks to listed aquatic plants and mammals (listed and nonlisted), however, are not expected at application rates 10.040lb a.i./acre and 50,023lb a.i./acre, respectively. Therefore, if the proposed maximum application rate for pyrasulfotole was reduced to 0.023 lb a.i./acre, direct adverse effects from pyrasulfotole

use would only be expected for terrestrial and semi-aquatic dicotyledonous plants. 'Listed' species are those which are currently on the Federal list of endangered and threatened wildlife and plants.

For dicots, the RQs ranged from 0.01 to 22.5 and from 0.56to 62 for non-listed and listed species, respectively. Predictions based on the AgDRIFT model indicate that dicots more than 390 

### fi (using the AE 03 17309 02 SE06 formulation) and 2,126 ft (usingthe AE 03 17309

### + Bromo formulation) from the treated use area may be exposed by spray drift to pyrasulfotole at levels above the EC25. The mammalian RQs calculated for chronic exposure range from 0.01 to 1.87 for dose-based RQs using upper 9oth percentile Kenagavalues. The RQs for three mammalian body-sizeldietary categories exceed the Agency's LOC for chronic exposure: 15 g and 35 

### g mammals that eat short grass (RQs = 1.87 and 1.6, respectively) and 15 g mammals that eat broadleaf plants/small insects (RQ = 1.05). All mammalian chronic RQs drop to <1 at application rates of 10.023Ib ailacre.

The non-listed species LOC for aquatic vascular plants was not exceeded in any ofthe use scenarios modeled, however, the listed species LOC was exceeded (RQ = 1.05; based on exposure estimates using the 

### TX Wheat scenario), indicating the potential for risk to listed aquatic vascular plants exposed to pyrasulfotole. The RQ for listed aquatic vascular plants drops to <1 at application rates of 10.040lb a.i./acre.

None ofthe aquatic animal RQs for chronic exposure exceeded the Agency's LOC, however, chronic toxicity data are not available for the most acutely sensitive aquatic animal taxon (i.e.,estuarinelmarine invertebrate). Although the chronic toxicity of pyrasulfotole to estuarinelrnarine invertebrates is uncertain, given that: (1)thepotential use sites for the proposed uses largely fall outside of estuarinelrnarine environments, with the possible exceptions of California and the mid-Atlantic states; (2) the aquatic EECs used in this assessment are based on a static water-body with no outlet, and, thus, are likely higher than concentrations expected in estuarinelrnarine environments; and (3) estuarinelrnarine invertebrates would need to be 1,293 times more sensitive to pyrasulfotole than freshwater invertebrates on a chronic-exposure basis to exceed the Agency's chronic risk LOC, risks to estuarinelmarine invertebrates from chronic exposure to pyrasulfotole are not expected.
Regarding listed species, EFED's screening level analysis shows the possibility of direct effects to listed aquatic vascular plants, terrestrial and semi-aquatic dicotyledonous plants, and mammals (chronic exposure). For indirect effects, all other taxa will be considered since there is a potential for indirect effects to taxa that might rely on plants and/or mammals for some stage oftheir life-cycle. Therefore, at this time, no Federallylisted taxa canbe excluded from the potential for direct andlor indirect effects from the proposed uses ofpyrasulfotole (see 

### Table 1). LOCATES identified a total of 817 listed species that overlapped at the county-level with areas where wheat, barley, oats, andlor triticale are grown. Among these species, 3 18 are dicots, 13 are aquatic monocots, and 59 are mammals. Therefore, at the county-level, there is the potential for a total of 390 listed species to be directly affected by pyrasulfotole use, while 427 species may be indirectly affected by the use ofthe chemical.TABLE 1. Listed Species Risks Associated with Potential Direct or Indirect Effects Due to the Proposed Applications of Pyrasulfotole on Cereal Grains. I I LISTED TAXON 

# I DIRECT EFFECTS 

# I INDIRECT EFFECTS

Terrestrial and semi-aquatic plants - monocots 

# I

Terrestrial and semi-aquatic plants - dicots 

# 1 Yes

Insects 

# I No 

# I yes1

Birds 

# 1 No 

# 1 yes'

Terrestrial phase amphibians

Aquatic plants 

# I
Yes 

# I yes' No

Reptiles

Mammals

Freshwater crustaceans No

Yes (chronic)

Freshwater fish

Aquatic phase amphibians

Mollusks No ----- yes'

yes'

Marinelestuarine crustaceans 

# I No 

# I yes1 No

No

I I 

### he nonlisted LOC was exceeded for terrestrial and semi-aquatic plants (dicots), the listed LOC was exceeded for aquatic vascular plants, and the chronic risk LOC was exceeded for some small mammals (535g)

. Therefore, the potential for adverse effects to those species that rely either on a specificplant or animal species (specifically aquatic vascular plants, terrestriallsemi-aquatic dicots, or mammals) or multiple plant or animal species (specificallyterrestriallsemi-aquatic dicots and mammals) cannot be precluded. Indirect effects may include general habitat modification, host plant loss, and food supply disruption. yes'

yes'



### E. Uncertainties and Data Gaps

There is no evidence ofpyrasulfotole degradation in aquatic environments. As such, pyrasulfotole was assumed stable in the ecological pond used to estimate aquatic exposure concentrations. Since the ecological pond (used in our modeling) has no outlet,there was a modeled accumulation of pyrasulfotle in the pond throughout the 30 year simulations. In the case ofpersistent compounds, a 1-in-10 year EEC does not reflect varying meteorological conditions that are expected once every ten years, since the yearly peaks are not independent but are actually correlated to the previous year's peak concentration. This results in acute and chronic exposure concentrations that are very similar (i.e,<2% difference between peak and 90-day average EECs). Pyrasulfotle concentrations in flowing water bodies are not expected to accumulate from year to year because of downstream dilution. Risk to aquatic plants resulting from accumulation of pyrasulfotle fiom multiple years of application is not likely in flowing systems.
Even though pyrasulfotole is very soluble and moderately mobile to mobile based on the results of batch equilibrium studies, in aerobic soil metabolism studiesunextractable residues were identified at maximums of 35-62% of applied radioactivity in three soils. Theunextractable residues are uncharacterized and it is uncertain whether they consist of degradates ofrisk concern. Under sterile conditions these unextractable residues were not formed suggesting that the formation ofthem is microbially mediated. Aerobic soil metabolism half-lives were estimated based on parent concentrations alone (excluding unextractable residues). To the extent that these unextractable residues are ofrisk
concern, the estimated half-lives will be underestimated compared to a total toxic residue approach for estimating half-lives. However, given the persistence of pyrasulfotle parent only, a total toxic residue approach for calculating aerobic soil metabolism half-life would not impact PRZMIEXAMS modeled EECs appreciably.

Because pyrasulfotole is persistent and has the potential to progressively bind to certain soilsthrough time as it degrades and forms unextractable residues, there is the potential for pyrasulfotole (or residues of concern) to accumulate in the benthos at levels that could result in toxic exposure to benthic and epibenthic aquatic organisms, especially those that consume soil. Thepotential risk to benthic and epibenthic organisms could not be assessed here, however, because a lack of available toxicity data for these taxa.
Additionally, estuarinelrnarine invertebrates (i.e., mysids) are considerably more sensitive to pyrasulfotole on 

### an acute exposure basis than the other aquatic animals tested, however, no toxicity data for chronic exposure are available for estuarinelmarine invertebrates. Because there is the potential for pyrasulfotole to accumulate in the benthos, as discussed above, the chemical could pose a chronic risk to benthic and epibenthic organisms (including some estuarinelrnarine invertebrates). However, given that: (1) the potential use sites for pyrasulfotole largely fall outside of estuarinelmarine environments; (2) the aquatic EECs used in this assessment are likely higher than the concentrations expected in most estuarinelmarine environments because they are based

on a static water-body with no outlet; and (3) estuarinelmarine invertebrates would need to be 1,293 times more sensitive to pyrasulfotole than freshwater invertebrates to exceed the Agency's chronic risk LOC, risks to estuarinelmarine invertebrates from chronic exposure to pyrasulfotole are not expected. However, the lack of data on the chronic toxicity ofpyrasulfotole to estuarinelrnarine invertebrates adds uncertainty to this risk assessment.I1 PROBLEM FORMULATION

The purpose ofthis assessment is to evaluate the environmental fate and ecological risks for the registration of the new chemical pyrasulfotole (also known as AE 0317309; (5- hydroxy-l,3-dimethyl-1 

### H-pyrazol-4-yl)(2-mesyl-4-trifluoromethylphenyl)methanone) (PC Code: 000692). As a new herbicide being proposed for use in the United States, EPA is required under the Federal Insecticide Fungicide and Rodenticide Act (FIFRA) to ensure that pyrasulfotole does not have thepotential to cause unreasonable adverse effects to the environment. Potential effects to listed species (i.e.,species on the Federal list of endangered and threatened wildlife and plants) are also considered under the Endangered Species Act in order to ensurethat the registration of pyrasulfotole is not likely to jeopardize the continued existence of such listed species or adversely modify their habitat. To these ends, this assessment follows EPA guidance on conducting ecological risk assessments (USEPA 1998) and the Office ofPesticide Program's policies for assessing risk to non-target and listed organisms (USEPA 2004).

Among the end products ofthe EPA pesticide registration process is a determination of whether a product is eligible for registration and, if so, a description ofhow the product may be used. A label represents the legal document which stipulates how and where a given pesticide may be used. End-use labels describe the formulation type, acceptable methods of application, where the product may be applied, and anyrestrictions on how applications may be conducted. Thus, the use, or potential use, described by the pesticide's labels is considered "the action" being assessed. This assessment is in support ofthe new chemical registration ofpyrasulfotole.

A. Stressor Source and Distribution

1. Source and Intensity
Pyrasulfotole, a systemic herbicide, is a new chemical that is undergoing registration (as the active ingredient in two end-use products) by the registrant Bayer Cropscience. The two pyrasulfotole (AE 0317309) end-use products being proposed for registration in the United States are AE 0317309 

### + Bromo Herbicide [with the following active ingredients (a.i.): 3.3% pyrasulfotole, 1 3.4% bromoxynil octanoate, and 12.9% bromoxynil heptanoate] and AE 0317309 SE06Herbicide [theonly a.i. is pyrasulfotole (4.4%)]. According to the proposed labels, both products would be used to control broadleaf weeds in wheat, barley, oats and triticale (an artificial hybrid ofrye and wheat). Pyrasulfotole would be applied as a post-emergent foliar sprayvia ground, aerial, or sprinkler irrigation application (limited to AE 03 17309

## + Bromo Herbicide for application to wheat and barley).

2. PhysicaUChemicaYFateand Transport Properties
Pyrasulfotole is expected to be persistent under certain conditions and mobile to moderately mobile (FA0classification) in the environment. There is no evidence ofdegradation in aquatic environments. Major routes of dissipation include microbial degradation in soils, formation ofnon-extractable residues in soils and sediments, and dilution.



### 3. Pesticide Type, Class, and Mode of Action
Pyrasulfotole is a phenyl pyrazolyl ketone herbicide. According to a risk assessment conducted by Bayer Cropscience 

### (MRID 468019-47), pyrasulfotole inhibits the enzyme 4-hydroxyphenylpyruvate dioxygenase (4-HPPD), and, thus, blocks the phenylquinone biosynthesis pathway in plants which leads to a decrease in carotenoids. Therefore, pyrasulfotole inhibits photosynthesis and pigment synthesis and causes bleaching symptoms, necrosis, and ultimately death in susceptible plants, especially those with young and still expanding leaves. Pyrasulfotole is mobile in the symplast (phloem) and apoplast (xylem) plant transport systems, and plant exposure is primarily through leaf uptake and translocation to the target site; only low amounts are taken up via the root system. Pyrasulfotole is intended to target dicotyledonous plants. The tolerance of cereal crops to pyrasulfotole is likely related to the faster metabolic degradation ofthe herbicide when compared to susceptible dicots.

4. Overview of Pesticide Usage

Sincethis is a new chemical, the Agency does not have any usage information for pyrasulfotole. Theproposed registration is for wheat, barley, oats, and triticale. Pyrasulfotole is a post emergence herbicide that is applied as a foliar spray (via ground, aerial, or sprinkler irrigation) one time a year at a maximum application rate of 0.045 Ib a.i./A. There are two pyrasulfotole end-use products being proposed for registration in the United States for use on wheat, barley, oats, and triticale. The two proposed formulations are AE 03 17309

### + Bromo Herbicide (an emuslsifiable concentrate containing 3.3% pyrasulfotole) and AE 03 17309 SE06 Herbicide (a suspo-emulsion containing 4.4% pyrasulfotole).



### B. Receptors

1. Aquatic and Terrestrial Effects

Table 2 gives examples oftaxonomic groups and species tested to help understand potential ecological effects ofpesticides to non-target organisms. Within each ofthese very broad taxonomic groups, a measure of effect from either acute or chronic exposure is selected from the available test data.

### TABLE 2. 

### Taxonomic Groups and Test Species Evaluated for Ecological Effects in Screening-Level Risk Assessments.



## I Dicots

- soybean (Glycinemax) Aquatic plants and algae 

## I Duckweed (Lemnagibba) Taxonomic Group ~irds'

Mammals Insects Freshwater fishz

Freshwater invertebrates Estuarinelmarine fish Terrestrial plants"



## I Green algae (Selenastrumcapricornutum)

I Birds rmresent surrogates for amphibians (terrestrial ~hase) and re~tiles. Example(s) of Representative Species Mallard duck (Anas platyrhynchos) Bobwhite quail (Colinusvirginianus) Laboratory rat (Rattusnorvegicus) Honey bee (Apismellifera L.) Bluegill sunfish (Lepomismacrochirus) Rainbow trout (Oncorhynchusmykiss) Water flea (Daphnia magna) Sheepshead minnow (Cyprinodon variegatus) Monocots

- corn (Zeamays)



### - . , Freshwater fish may be surrogates for amphibians (aquaticphase). Four species of two families of monocots, of which one is corn; six species of at least four dicot families, of which

one is soybeans.



### 2. Ecosystems Potentially at Risk

The ecosystems potentially at risk include the areas adjacent to the application sites and water bodies adjacent to the application sites and downstream. In addition, organisms that use the application site as part oftheir habitat (e.g.,birds foraging for insects within application areas) are also considered to be part of the ecosystems potentially at risk.



### C. Assessment Endpoints

FIFRA Part 158 guideline toxicity tests (CFR 40 $ 158.202,2002) are intended to determine pesticidal effects on a variety of organisms, including birds, mammals, fish, terrestrial and aquatic invertebrates, and plants. Thesetests include both short-term and long-term exposure periods and evaluate the survival, reproduction, and/or growth of laboratory species. The studies, when available, areused to evaluate the potential of a pesticide to cause adverse effects, to determine whether further testing is required, and to determine the need for precautionary label statements to minimizethe potential adverse effects to non-target animals and plants 

### (CFR 40 $158.202,2002).
Assessment endpoints are intended to represent valued attributes of the environment that, if detrimentally altered, could pose a risk to the environment. The assessment endpoints ofthis ecological risk assessment include terrestrial and aquatic animal and plant mortality following acute exposure to pyrasulfotole and terrestrial and aquatic animal reproduction, growth and survival effects from chronic exposureto pyrasulfotole. Surrogate species are used to represent all fi-eshwaterfish (2000-t) and bird (680+) species in the United States. For mammals, acute studies are usually limited to the Norway rat or the house mouse. Usually data fi-omestuarine/marine testing is limited to a crustacean, a mollusk, and a fish. The assessment of risk or hazard makes the assumption that avian toxicity is similar to terrestrial-phase amphibians and reptiles, unless more appropriate data are available. The same assumption is made for fish andaquatic-phase amphibians. The most sensitive toxicity endpoints areused from surrogate test species to estimate treatment-related direct effects on mortality and reproductive and growth assessment endpoints.

For terrestrial and semi-aquatic plants, the screening assessment endpoints for non-target species (crops and non-crop plant species) are based on the emergence of seedlings and vegetative vigor of annuals. Measures of effect for this assessment focus on impacts on plant emergence and/or on active growth.

For aquaticplants, the assessment endpoint is the maintenance and growth of standing crop or biomass. Measures of effect for this assessment focus on nonvascular, e.g., algae, and vascular plant, e.g., duckweed (Lemnagibba), growth rates and biomass measurements.

The Agency acknowledges that pesticides have the potential to exert indirect effects upon listed organisms by, for example, perturbing forage or prey availability, altering the extent ofnesting habitat, and creating gaps in the food chain. In conducting a screen for indirect effects, the endpoints for each taxonomic group areused to make inferences concerning the potential for indirect effects upon listed species that rely upon non-listed organisms asresources critical to their life cycle.

The endpoints are typically derived from registrant-submitted studies which have undergone review and were classified as "acceptable" (conducted under guideline conditions and considered to be scientifically valid) or "supplemental" (conditions deviated from guidelines but the results are considered to be scientifically valid). For

more details on EFED7s study classification system and study guidelines, see USEPA 2004.
Assessment endpoints can also be derived from the open literature. Guidelines for incorporation of open literature into ecological risk assessments are described in USEPA (2004). Toxicity data from the open literature are identified via the ECOTOX search engine, maintained by EPA/ORD. In order to be included inthe ECOTOX database, papers must meet several criteria (again, seeUSEPA 2004 for details). Data that pass the ECOTOX screen are evaluated relative to the data provided by the registrant, and may be incorporated qualitatively or quantitatively into the risk assessment. Specific studies may warrant inclusion in the risk assessment when:

(I)tested endpoints are more sensitive than those in registrant data; (2) the test data arebased on under represented taxa; (3) the data include ecologically relevant endpoints not normally evaluated in registrant studies

ECOTOX identified a total of four pyrasulfotole studies from the open literature, all of which were rejected by ECOTOX because they were not written in English (i.e., they were written in German) (see APPENDIX A). Therefore, no open literature studieswere reviewed for assessment endpoints.Although all endpoints are measured at the individual level, they can provide some insight about the potential for adverse effects at higher levels of biological organization (e.g.populations and communities). For example, pesticide effects on individual survivorship have important implications for both population rates and habitat carrying capacity.

D. ConceptualModel

The conceptual model used to depict the potential ecological risk associated with pyrasulfotole is fairly generic and assumes that as a systemic herbicide, pyrasulfotole is capable of affecting terrestrial and aquatic organisms (animals and plants) provided environmental concentrations are sufficiently elevated as a result ofproposed label uses. Additionally, based on a preliminary risk screening indicating that pyrasulfotole is highly toxic to some plants, the hypothesis for the risks ofpyrasulfotole to non-target organisms (depicted in Figure 1)focuses on aquatic and terrestrial environments. Therefore, we will consider potential exposure as a result of direct applications, spray drift, and runoff.

1. Risk Hypotheses

For this assessment, the risk to non-target organisms is based on potential effects from the application of pyrasulfotole to the environment. The Agency presumes the following risk hypothesis for this screening level assessment:

Based on mode ofaction and the sensitivity ofnon-target aquatic and terrestrial species (especially plants), the proposed agricultural uses of pyrasulfotole have thepotential to reduce survival, reproduction, and/or growth in terrestrial and aquatic animals and plants through direct application, spray drift and/or runoft

In order for a chemical to pose an ecological risk, it must reach non-target organisms at concentrations found to cause adverse effects. The assessment of ecological exposure pathways in this assessment includes an examination ofthe source and potential migration pathways to pyrasulfotole exposure, and the determination of potential adverse effects on non-target species.

2. Diagram
Application methods for pyrasulfotole involve foliar spray applications via ground, aerial, and sprinkler irrigation. Ecological receptors that may potentially be exposed to pyrasulfotole include terrestrial and semi-aquatic wildlife (i.e.,mammals, birds, amphibians, terrestrial invertebrates, and reptiles) and plants. In addition, aquatic receptors (e.g.,freshwater and estuarinelmarine fish and invertebrates, amphibians, and plants) may alsobe exposed as a result of potential movement ofpyrasulfotole via spray drift andlor runoff from the site of application to aquatic environments. The assessment following theprocess depicted in Figure 1 forms thebasis for identifying potential endpoints, stressors, and ecological effects associated with pyrasulfotole use.This assessment does not take into account atmospheric transport in estimating environmental concentrations, nor does it account for ingestion of pyrasulfotole residues by animals in drinking water or contaminated grit, ingestion through preening activities,

or uptake through inhalation or dermal absorption by terrestrial animals. Exposure to terrestrial animals isbased primarily on dietary consumption of foliar residues while aquatic assessments assume that all major potential routes of direct exposure are accounted for.Stressor 

# I Pyrasulfotole applied as a groundaerial spray to cereal grains 

# I

Birds, Mammals, Reptiles, Terrestrial Phase Amphibians Aquatic Invertebrates Vertebrates 

# 1

Individual vertebrates and invertebrates

Reduced survival

orreproduction I 

## 1 

# 1

FIGURE 1: Conceptual Plan Diagram Depicting Sources of Exposure, Potential Receptors and Adverse Effects from the Proposed Uses of Pyrasulfotole. Source/ Transport

E. Analysis Plan Spray Direct Application Runoff Drift A ToField

As with anypesticide, there is concern regarding the potential effects pyrasulfotole use may pose to non-target animals and plants. This document characterizes the environmental fate of pyrasulfotole to assess whether proposed label uses of pyrasulfotole on wheat, barley, oats and triticale provide a means of exposure to nontarget species. Additionally, the toxicity ofpyrasulfotole is characterized, then both potential exposure and effects are integrated to estimate the likelihood of adverse effects (risk) to non-target Federally listed (endangered or threatened) and non-listed animals and plants that could potentially impact the registration decision ofpyrasulfotole under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), the Food Quality Protection Act (FQPA), and the Endangered Species Act (ESA). Pathways

A Source1 Exposure Media Terrestrial Food Ripariad Receiving Items (foliage, fruit, Wetland Water Body/ insects, seeds) FoliageISoil Sediment

I 

# 4 

# 1

Direct contact/ Direct contact/ Exposure Ingestion Root Uptake Root Uptake uptake/ Gill1 Route Integument Adsorption Uptake

Terrestrial Wetland1 Aquatic 

# 1

Receptors Upland Riparian Plants Plants Plants

Attribute Individual Animals Individual Plants Changes Reduced survival Reduced survival,

orreproduction growth, or reproduction Reduced population growthThe maximum proposed label application rates for use ofpyrasulfotole on wheat, barley, oats, and triticale were selected for modeling environmental concentrations for this screening-level deterministic (risk-quotient based) assessment. Themost sensitive toxicity endpoints from surrogate test species are used to estimate treatment-related effects on growth, and survival. Estimated environmental concentrations (EECs)used in terrestrial and aquatic ecological risk assessments are based solely onpyrasulfotole parent compound, although the potential effects of the degradate RPA 203328 are considered (see page 37).

In the following sections, we characterize the use, environmental fate, and ecological effects ofpyrasulfotole and, using a risk quotient (ratio of exposure concentration to effects concentration) approach, we estimate the potential for adverse effects on nontarget terrestrial and aquatic animals and plants. Although risk is often defined as the likelihood and magnitude of adverse ecological effects, the risk quotient-based approach does not provide a quantitative estimate of likelihood and/or magnitude of an adverse effect. Such estimates may be possible through a more refined, probabilistic assessment; however, they arebeyond the scope ofthis screening-level assessment.

1. Preliminary Identification of Data Gaps and Methods

No preliminary data gaps or method issues that would preclude a risk assessment were identified.

2. Measures to Evaluate Risk Hypotheses and Conceptual Model

a. Measures of Exposure

Measures of exposure arebased on terrestrial and aquatic models that estimate environmental concentrations ofthe chemical being assessed using labeled application rates and methods. The measure of exposure for aquatic species is the estimated environmental concentration (EEC) expected once every ten years based on 30 years of simulations. The 1 -in-10year peak concentration is used for estimating acute effects to aquatic vertebrate and invertebrate species; the 1 -in-1 0 year 2 1 -day mean concentration is used for assessing aquatic invertebrate chronic exposure; and the1-in- 10year 60-day mean concentration is used for assessing chronic exposure for fish (and aquatic-phase amphibians). The terrestrial measure of exposure for vertebrate and invertebrate animals is the upper 9oth percentile concentration normalized for application rates on various dietary items.
Exposure for terrestrial plants inhabiting dry and semi-aquatic areas (i.e.,low-lying wet areas that may dry up at times throughout the year) isbased on the following:

(1) the pesticide's water solubility and the amount ofpesticide present on the soil surface and its top one centimeter, (2)potential "sheet runoff" (one treated acre to an adjacent acre) for dry areas,

### (3) potential "channel runoff' (1 0 acres to a distant low-lying acre) for semiaquatic or wetland areas, (4) fraction runoff values of 0.01, 0.02, and 0.05 for water solubilities of <lo, 10- 100, and <100ppm, respectively, and (5) an assumption of 1 % spray drift for ground application and 5% for aerial, airblast, forced air, and spray chemigation applications.

The registrant has provided a suite of studies pertinent to most Subdivision N guidelines, which provide environmental fate data for these measures of exposure.

b. Measures of Effect

Measures of effect are obtained from a suite ofregistrant-submitted guideline studies conducted with a limited number of surrogate species. The test species are not intended to be representative ofthe most sensitive species but rather are selected based on their ability to thrive under laboratory conditions. The acute measures of effect routinely used for listed and non-listed animals in screening level assessments are the LDS0, LCs0or ECS0, depending on taxa (see Table 3). LD stands for "Lethal Dose", and LDS0 is the amount of a material, given all at once, that is estimated to cause the death of 50% of a group oftest organisms. LC stands for "Lethal Concentration" and LCs0is the concentration of a chemical that is estimated to kill 50% of a sample population. EC stands for "Effective Concentration" and the ECS0 is the concentration of a chemical that is estimated to produce somemeasured effect in 50% ofthe test population. Endpoints for chronic measures of exposure for listed and non-listed animals are the NOAEL or NOAEC. NOAEL stands for "No Observed-Adverse-Effect-Level" and refers to the highest tested dose of a substance that has been reported to have no harmful (adverse) effects on a test population. The NOAEC (i.e.,"No-Observed-Adverse-EffectConcentration") is the highest test concentration at which none ofthe observed results were statistically different from the control. For non-listed plants, only acute exposures are assessed (i.e.,ECI5for terrestrial plants and ECS0 for aquatic plants). For listed terrestrial plants the Agency uses the ECSor NOAEC (see Table 3).

Consistent with EPA test guidelines, the registrant has provided a suite of ecological effect data that comply with good laboratory testing requirements.Aquatic Animals (Freshwater.fish and inverts. and estuarine/marine fish and inverts.) TABLE 

### 3. Acute and Chronic Measures of Effect.

Terrestrial Animals Birds TAXA ASSESSMENT

Acute MEASUREOF EFFECT

Lowest tested ECsoorLCso(acute toxicity tests)

Chronic I Lowest NOAEC (early life-stage or full life-cycle tests)

Acute/Subacute Lowest LDS0 (single oral dose) and LCso(subacute dietary)

Chronic Lowest NOAEC (2 1-week reproduction test) 

# I Terrestrial Animals

Mammals I I 

# I Acute

Chronic

Plants Terrestrial non-listed (monocots and dicots)

Lowest EC5orNOAEC (seedling emergence and vegetative vigor) Lowest LD50(single oral dose test)
Lowest NOAEC (two-generation reproduction test)

Plants Terrestrial listed (monocotsand dicots) I

Acute

Acute

111. ANALYSIS Lowest EC2, (seedling emergence and vegetative vigor)

Plants Aquatic (vascularand algae)

A. Use Characterization

Theproposed pyrasulfotole registration is for wheat, barley, oats, and triticale. Based on National Agricultural Statistics Service (NASS) 2006 data, approximately 3,500,000

acres ofbarley; 57,900,000 acres of wheat; and 4,300,000 acres of oats are planted each year in the United States (see Figs. 2,3,and 

### 4). The most recent NASS report available for triticale is from 2002 (no map is available). According to this report, a total of 20,292

acres oftricale was grown in 27 U.S. states in 2002. The state with the most acreage grown was Kansas (6,588 acres) followedby Washington (2,288 acres), Texas (2,032 acres), Oregon (1,869 acres) and Nebraska (1,563 acres). Theremaining states each grew less than 1,000acres of triticale. These represent potential markets for pyrasulfotole in the United States. Acute Lowest EC50Barhy 2005 PlantedAcres by County

FIGURE 2. Acres ofBarley Grown By County in the United Stated in 2005 (based

on information from USDA-NASS).All Wheat 2005 PlantedAcres by County

FIGURE 

### 3. Acres of Wheat Grown By County in the United Stated in 2005 (based on information from USDA-NASS).Oabm5 Planted Acmtry County

FIGURE 4. Acres of Oats Grown 

### By County in the United Stated in 2005 (based on information from USDA-NASS).
Pyrasulfotole, a post emergence herbicide, is applied as a foliar spray (via ground, aerial,

or sprinkler irrigation) to actively growing cereal crops from one leaf up to flag leaf emergence (approximately 7-45 days post emergence for spring wheat and 7-2 10days post emergence for winter wheat). There are two pyrasulfotole end-use products being proposed for registration in the United States: AE 03 17309

### + Bromo Herbicide (an emuslsifiable concentrate with the following a.i.: 3.3%pyrasulfotole, 13.4% bromoxynil octanoate, and 12.9% bromoxynil heptanoate) and AE 03 17309 SE06 Herbicide (a suspoemulsion containing 4.4% pyrasulfotole, and no other active ingredients). According to the proposed labels, pyrasulfotole can be applied at a single maximum application ratelyear of 0.045 lb ailacrefor ground and aerial applications and 0.037 lb a.i./acrefor sprinkler irrigation application (limited to use on wheat and barley) (see Table 4). Only

one application per year is allowed.

### TABLE 4. 

### Application Information from the Proposed Pyrasulfotole Labels. PRODUCT (% a.i.) 

## 1 USES 

### 1 APPLICATION 

## I MAX. 

### I MAX. NUMBER



### B. Exposure Characterization AE 03 17309+ Bromo

Herbicide (3.3%)

AE 0317309 SE06 Herbicide (4.4%)



### ' The application rate on the

1. 

### Environmental Fate and Transport Characterization
Pyrasulfotole is highly soluble in water (69 

### g/L), has a low vapor pressure (6.8 x 1 

## o-~ Pa) and low octonal-water partitioning coefficient (0.04). Therefore, volatilization from water and soil surfacesis not expected to be an important route of environmental dissipation and bioaccumulation is unlikely. Pyrasulfotole is stable to hydrolysis and photolysis and moderately susceptible to microbial degradation under aerobic conditions in soils. Pyrasulfotole is expected to be persistent under certain conditions and moderately mobile to mobile (FA0classification) in the environment. Major routes of dissipation include microbial degradation in soils, formation of unextractable residues in soils and sediments, and dilution. Depending on soil, site and meteorological conditions pyrasulfotole may be transported off-site via runoff, leaching and spray drift. 

### Table 5 summarizes the environmental chemistry, fate and transport properties ofpyrasulfotole. Further details on the environmental fate and transport studies are found in 

### APPENDIX B. glcc; the fonnulation is 3.3%pyrasulfotole and a max application rate of 15oz of formulated productlacre is allowed. 

### ' The application rate on the label was converted to Ibs a.i./acrebased on the following: The formulated product density = 1.141 1 glcc; the formulation is 4.4%pyrasulfotole and a lnax application rate of 13.7oz of formulated productlacre is allowed. Wheat

Barley

Oats

Triticale

Wheat

Barley

Oats

Triticale

label was converted to Ibs METHODS

Ground Aerial Sprinkler Irrigation

................................................ Ground Aerial Sprinkler Irrigation

................................................. Ground Aerial

................................................ Ground Aerial Ground Aerial

................................................ Ground Aerial

................................................ Ground Aerial

................................................ Ground Aerial a.i./acrebased on the following: APPLICATION RATE/ YEAR

0.037 lb a.i./acrel

0.045 lb a.i./acre2

Theformulated product density OF APPLICATIONS1 YEAR 1

1

= 1.1417Selected Phvsical/Chemical Parameters TABLE 5. Summary of Environmental Chemistry, Fate and Transport Properties of Pyrasulfotole.

Molecular weight 

## 1 362.3glmol 

## 1 REFERENCE1 COMMENTS PARAMETER

PC code
CAS NO.
Chemical name

Chemical formula VALUE

000692
365400-1 1-9 (5-hydroxy-l,3-dimethylpyrazol-4-yl)(a,a,a-trifluoro2-mesyl-p-toly1)methanone
C~HI~C~~N

Product chemistry; very soluble Water solubility (20"C) pH 4 pH 7 VH9 Vapor pressure 4.2g/L 69 g/L 49 g/L
Product chemistry; nonvolatile

Photolysis in soil Kow (1% Kow)
PH 4 PH 7 PH 9

MRID 46801707 Environmental phototransformation half-life based on sunlight expected in Pheonix, AZ (33.26" N) 1.89 (0.276) 0.044(-1.36) 0.026 (-1.58) Product chemistry; not likely to bioaccumulate

Persistence

Aerobic soil metabolism

Anaerobic soil metabolism
Aerobic aquatic metabolism Anaerobic aquatic metabolism MRID 46801705
MRID 46801706 Hydrolysis Photolysis in water Stable (pH = 5,7,9)
Stable

MRIDs 46801709, 46801710,46801711

2 compartment, 4 parameter exponential model (DFOP)

MRID 46801712

MRID 46801713

MRIDs 46801714, 46801715 Soil Texture Loamy sand

Silt loam
Sandy loam

Mobility Batch equilibrium Stable

Stable

Stable DT~o (dl
5.8

63

23

Soil Texture Silt loam Loamy sand DT~o (dl

749

1424

208 0.977

0.998
0,990



### ~f'
0.98
1.2 1/N
0.93
0.91 &
21
100 MRID 46801703

# I
PARAMETER VALUE REFERENCE1 

# I
COMMENTS Clay loam
Sandv loam



# I ( based on low vapor Laboratory volatility 0.34
0.39
Silt loam Sandy loam

pressure Field Dissipation

I I I Manitoba 19.2d 1531d 119 

# I model (DFOP) 0.98
0.95

Washington
Saskatchewan


## I Ontario 

## 1 18d 

## 1 178d 18.9 

## I 20
35
3.2
16

Terrestrial field dissipation



## I Bioaccumulation NA

DTS0 8.9 d
5.7 d Location Kansas
North Dakota
5.7d
10d 0.93
0.83 Volatility not likely

a. Degradation 213
345

DTgO 45 d
44 d
213d
260d

Accumulation in fish, BCF

Under aerobic conditions pyrasulfotole degraded in 

### 3 soils (Goldsboro loamy sand, LaDelle silt loam, sandy loam from Germany) according to an apparent bi-phasic pattern with observed DTsosranging from 4-65 d and observed DT90sranging from >120->358 d. A 2-compartment, 4-parameter exponential model, also known as Double First Order in Parallel (DFOP), was used to fit the data and resulted in modeled DTsOs ranging from 6- 63 d and DT90sranging from 208-1424 d (MRIDs 46801709,406801710,468017 11). The DFOP model was used to fit the data because it appeared to describe the data better than alternative models (see Appendix B for details). Degradation products included pyrasulfotole-benzoic acid (AE B 197555),C02 and unextractable residues. Unidentified extractable residues were identified at maximums of 52.6-14%. Soil samples were extracted using one solvent system [acetonitrile: water (2:1,v:v) ] with an Accelerated Solvent Extraction (ASE) system, which conducted a two-phase ["mild" (40°C, 103 bar) and "aggravated" (1OO°C, 103 bar) conditions] extraction. Unextractable residues were identified at maximums of 35-62% of applied radioactivity in the 3 soils. The unextractable residues are uncharacterized and it is uncertain whether they consist of degradates of risk concern. Under sterile conditions, however, the formation of unextractable residues (as well as the formation of COz and the benzoic acid degradate) were negligible. In terrestrial field dissipation studies pyrasulfotole dissipated from the whole soil profile with modeled (DFOP) DTgOs ranging 44-53 1 d and the amount oftotal residue (excluding unextractable residues which are not measured in these studies) carry % carry over 4.7
7.7
11
37

I. Units of (mg/kg)/(mg/~)"N, where IIN is the Freundlich exponent. 2. Approximation calculated from the Freundlich coefficient, per standard EFED guidance. NOdata MRIDs 468017 16, 46801717,46801718, 46801719

2 compartment, 4 parameter exponential

Bioaccumulation is not expected based on low log KO,over to the following growing season ranged from 4.7 to 37% (MRIDs 46801716, 46801717,46801718,46801719).

In aquatic systems, pyrasulfotole is stable to hydrolysis and photolysis (MRIDs 46801705,46801706). In aerobic aquatic metabolism studies, pyrasulfotole variably partitioned to the sediment and formed unextractable residues but there was no evidence of degradation. In a pond water-sandy loam sediment (water pH 4.8, sediment pH 4.9, pyrasulfotole residues partitioned from the water layer to the sediment with water:sediment ratios of 100:1 at day 0,2:1 at day 55, 1:4 at day 88 and were 1:>lo thereafter. Unextractable residues were identified at a maximum of 73% at study termination. In a pond water-silty clay sediment (water pH 7.5, sediment pH 6.9), pyrasulfotole residues partitioned from the water layer to the sediment with water:sediment ratios of 100:1at day 0, 3:1 at days 2 1, and were 2: 1thereafter. Unextractable residues were identified at maximums of 13% at day 104and were 1 1 % at studytermination. The more acidic pond water-sandy loam sediment resulted in substantially more partitioning to the sediment and formation ofunextractable residues than the less acidic pond water-silty clay sediment system. The pH ofthe more acidic system approaches the pKa from pyrasulfotole (pKa =4.2). Pyrasulfotole is considered stableto microbial degradation in aquatic systems (MRID 468017 13). Under anaerobic conditions pyrasulfotole is also stable (MRIDs 46801712,4681714,46801 715).

b. Mobility and Transport
Batch equilibrium studies resulted in organic carbon sorption coefficients (kc) ranging from 20 to 345 ml/g,, with a median value of 68ml/aC (MRID 46801 703). There is

some evidence the pyrasulfotle may become less mobile as it undergoes microbial degradation under certain conditions. In a supplementary experiment during the aerobic soil metabolism studies, the potential mobility ofpyrasulfotole appeared to decrease with time from moderately mobile (LC values of 276-357) at 50 days posttreatment to slightly mobile (&, values of 2,090-2,183) at 358 days in the Goldsboro loamy sand (pH = 5.6) (MRID 46801 709). However, in the LaDelle silt loam (pH = 7.0), the potential mobility ofpyrasulfotle appeared to remain mobile (Kc of 88) after one year posttreatment (MRID 46801710).

In terrestrial field dissipation studies, pyrasulfotole showed variable downward migration in the soil profile under bare soil conditions. In some studies, pyrasulfotle was confined to 0-15 cm whereas in others, it was detected at quantifiable levels as deep as 75-90 cm (MRIDs 46801716,46801717,46801718,46801719).

Sincepyrasulfotole has a Kd less than 5 in most soils and ispersistent (stable to hydrolysis, phtolysis and onlymoderately susce tible to aerobic degradation in soils), is 

# If not volatile (Henry's Law constant of 3.5 

### x 10- atm-m4/mol), and shows movement to 90 cm during some field dissipation studies, there is potential for groundwater contamination (Cohen, 1984).c. Field Studies

The soil dissipation/accumulation ofpyrasulfotole under bare ground and cropped (wheat) conditions was studied in Kansas, North Dakota, and Washington in the United States (MRIDs 46801716,46801717,46801 718), and under bare ground conditions in Saskatchewan, Manitoba, and Ontario in Canada (MRID 46801 719). Under bare ground conditions, pyrasulfotole dissipated from the entire soil profile with DTSOs and DTgOs (DFOP) ranging from 5.7 -18 d and 44

- 531 d, respectively. Carryover oftotal residues (excluding unextractable residues which are not measured in these studies) in the soil column to the following growing season was 4.7

- 37 %in the various studies.
Pyrasulfotole was not detected (above LOQ) below 15 cm at the Kansas, North Dakota and Ontario sites. Pyrasulfotole was detected (above LOQ) as deep as 75-90 cm at the Washington site and as deep as 30-45 cm at the Saskatchewan and Manitoba sites. The major transformation product, pyrasulfotole-benzoic acid (AE B197555), was not detected (above LOQ) below 15cm at the Kansas, North Dakota and Manitoba sites. It was detected (above LOQ) as deep as 45-60 cm at the Washington site, and as deep as 15-30cm at the Saskatchewan and Ontario sites.

d. Degradates

There was one major degradate, pyrasulfotole-benzoic acid (2-mesyl-4- trifluoromethylbenzoic acid; RPA 203328; AE B197555), detected in the aerobic soil metabolism and terrestrial field dissipation studies. Pyrasulfotole-benzoic acid is highly mobile with measured 

### kc of 0.9

- 1.5mllg,, (MRID 4681704). Based on available ecological effects data (see page 37), exposure to pyrasulfotole-benzoic acid is not assessed because it is not ofrisk concern.

Unextractable residues were identified at maximums of 35-62% of applied radioactivity in the aerobic soil metabolism studies. The unextractable residues are uncharacterized and it is uncertain whether they consist of degradates of risk concern or ofparent pyrasulfotole. Under sterile conditions, however, the formation of unextractable residues (as well as the formation of C02and the benzoic acid degradate) were negligible.

2. Measures of Aquatic Exposure

a. Aquatic Exposure Modeling

Tier I1 modeling for selected scenarios representing proposed uses was used to generate estimated environmental concentrations (EECs). For Tier 11, two models are used in tandem: the Pesticide Root Zone Model, (PRZM, Carsel et al., 1997)and the Exposure Analysis Modeling System (EXAMS, Burns, 1997). PRZM (3.12 beta dated May 24, 2001) simulates fate and transport on the agricultural field, and EXAMS (2.98.04, dated July 18,2002) simulates the fate and resulting daily concentrations in the water body. Simulations are carried out with the linkage program shell, PE4VOl .pl (dated August 13, 2003), which incorporates the standard crop and orchard scenarios developed by EFED. Simulations are run for multiple (usually 30) years, and the EECs represent peak valuesthat are expected once every ten years based on the thirty years of daily values generated during the simulation. Additional information on these models can be found at: http://www.epa.~ov/oppefed l/models/water/index.htm.
For aquatic endpoints, the exposure is estimated for the maximum application pattern to a 10-ha field bordering a 1-ha pond, 2-m deep (20,000 m3) with no outlet. Exposure estimates generated using this standard pond are intended to represent a wide variety of vulnerable water bodies that occur at the top of watersheds including prairie pot holes, playa lakes, wetlands, vernal pools, man-made and natural ponds, and intermittent and first-order streams. As a group, there are factors that make these water bodies more or less vulnerable than the standard surrogate pond. Static water bodies that have larger ratios ofpesticide-treated drainage area to water body volume would be expected to have higher peak EECs than the standard pond. These water bodies will be either smaller in size or have large drainage areas. Smaller water bodies have limited storage capacity and thus may overflow and carry pesticide in the discharge, whereas the standardpond has no discharge. As watershed size increases beyond 1 0-ha, it becomes increasingly unlikely that the entire watershed isplanted with a non-major single crop that is all treated simultaneously with the pesticide. For major crops like cereal grains, however, this may not be the case. Headwater streams can also have peak concentrations higher than the standard pond, but they likely persist for only short periods oftime and are then carried and dissipated downstream.
OPP standard PRZM crop scenarios, which consist oflocation-specific soils, weather, and cropping practices, were used in the simulations to represent proposed labeled uses of pyrasulfotole. These scenarios were developed to represent high-end exposure sites in terms ofvulnerability to runoff and erosion and subsequent off-site transport of pesticide. Pyrasulfotole isbeing proposed for use on wheat, barley, oats and triticale. All available OPP standard PRZM scenarios for wheat were modeled, ND wheat, OR wheat OP, and TX wheat OP. These wheat scenarios are also considered surrogates for the other cereal grain uses on the label (oats, barley and triticale). The Texas and Oregon scenarios were developed for the organophosphate (OP) cumulative drinking water assessment and as such were developed to be vulnerable to cumulative OP exposure and may not be vulnerable for single chemicals or other chemical classes on a national scale. A summary of the crop scenarios used to estimate pyrasulfotole concentrations in the aquatic systems for ecological risk assessment are listed in Table 6.

TABLE 

### 6. Sum1

PYRASULFOTOLE 

# 1

USE larv of Cro~ Scenarios

CROP SCENARIO

ND wheat: Cass County, Bearden silty clay loam

ORwheat: Willamette Valley, Bashaw clay

- TX wheat: Blacklands prairie, Crockett fine sandy loam STATION CHARACTERIZATION

MLRA 2; W24232 Winter wheat, OP scenario

MLRA 87; W13958 Winter wheat, OP scenarioPRZMiEXAMS modeling was done using the proposed maximum label rate. Input parameters are listed in Table 7. Pesticide applications were simulated as aerial spray applications. The proposed label recommends applying pyrasulfotole between 1" leaf and flag leaf (approximately 

### 7-45 days post emergence for spring wheat and 7-210days post emergence for winter wheat). The first date of application was chosen to be one week post-emergence, although applications are expected anytime during the application window.

SincePRZMiEXAMS require first order half-lives (rate constants), they were estimated by dividing the DFOP-modeled DTgO by 3.32 (the ratio between DT5() and DT90for first order reactions). Modeling inputs were selected according to EFED's Input Parameter Guidance (USEPA 2002). An aerobic soil metabolism first order half-life of439 d (the upper 90th percentile confidence bound on themean) was used. A soil organic carbon partitioning coefficient (&,) of 122ml/h,, the mean of six soils, was used.TABLE 7. PRZMIEXAMSInput Parameters for Aerial Application of Pyrasulfotole to Cereal Grains. 

## I INPUT PARAMETER VALUE
0.045 (0.05) SOURCE
AE 0317309 SE06 Herbicide (4.4%) lbs a.i./A (kg a.i.1ha)
Label maximum 

# IApplications per year AE 03 17309 SE06 Herbicide (4.4%)
Date of application

ND Wheat OR Wheat TX Wheat Chemical application method (CAM) IPSCND Input 7 days post emergence May 22"d September 8th October 17" AE 03 17309 SE06 Herbicide (4.4%) Assumption Foliar application 

# I

pesticide remaining on foliage after harvest is converted to surface 

## I

Spray drift fraction 

# I Input parameter 

# IApplication efficiency Input parameter guidance1 Aerial spray default

Product chemistry Product chemistry
Calculated 

## IWater solubility (mg/L) Product chemistry
MRID 46801703 Organic carbon-water partition coefficient

Aerobic soil metabolism MRIDs 46801709, 46801710,46801711 on the mean where tl12 is estimated by

metabolism tIl2 (d) MRID 46801713

Anaerobic aquatic metabolism tl12 (d) Hydrolysis tl12 (d) Photolysis tIl2 (d)
I. EFED input parameter g httn:llwww.c~a.~ovlo~ncfe~ MRIDs 46801714, 46801715
MRID 46801705 stable 

# I

0
0
dance is located llmodels/water/i~ stable
MRID 46801706

t: )ut guidancc2 28 O2.htn

The EECs listed in Table 

### 8 reflect maximum 1 -in-10 year surface water concentrations based on the proposed maximum application rates for aerial applications to wheat, barley, oats, and triticale (see APPENDIX C for the output data from the 

### ND Wheat, OR Wheat, and TX Wheat scenarios).Table 8. Tier 

### I1 Surface Water 1-in-10-Year Estimated Environmental

The ecological pond modeled with EXAMS is a static water body of fixed volume with

no outlet. Sincepyrasulfotole ispersistent in aquatic environments and since the ecological pond has no outlet, there was a modeled accumulation ofpyrasulfotle in the pond throughout the 30 year simulations. Exposure endpoints, in this assessment, are based on yearly peak concentrations. In the case ofpersistent compounds, a 1-in-10 year 

### EEC does not reflect varying meteorological conditions that are expected once every 10 years, since the yearly peaks are not independent but are actually correlated to the previous year's peak concentration.

b. Aquatic Exposure Monitoring and Field Data Concentrations (EECs) of Pyrasulfotole from Cereal Grain Use

There were no national-scale monitoring data for pyrasulfotole available for this assessment. PRZM SCENARIO

ND wheat

OR wheat

TX wheat (ppb).

3. Measures of Terrestrial Exposure 60-DAY

7.7

6.5

9.9

a. Terrestrial Exposure Modeling 90-DAY

7.6

6.4

9.9

The application method for the proposed pyrasulfotole use on cereal grains is limited to foliar spray (ground, aerial, and sprinkler irrigation), therefore, for this terrestrial exposure assessment, we consider only foliar applications. The EEC values used for terrestrial animal exposure are derived from the Kenaga nomograph, as modified by Fletcher et al. (1994), based on a large set of actual fieldresidue data. The upper limit values from the nomograph represent the 95th percentile ofresidue values from actual field measurements (Hoerger and Kenaga, 1972). TheFletcher et al. (1994) modifications to the Kenaga nomograph are based on measured field residues from 249 published research papers, including information on 1 18 species of plants, 121 pesticides, and 17 chemical classes. Thesemodifications represent the 95th percentile ofthe expanded data set. Risk quotients are based onthemost sensitive LCsoand NOAEC for birds (bobwhite quail and mallard duck) and LD50for mammals (based on lab rat studies). 21-DAY

7.7

6.5

10 APP. RATE (Ibs a.i./Alyr)

0.045

0.045

0.045

We derive terrestrial estimated environmental concentrations (Table 9) for pyrasulfotole using the maximum proposed single application rates. Terrestrial exposure estimates for avian and mammalian risk assessments were derived using the T-REX model (version 1.3.1, December 22,2006). A complete description ofthe input parameters and output is PEAK

7.7

6.5

10 4-DAY

7.7

6.5

10contained in APPENDIX 

### D. Exposure to upland and wetland plants is estimated using the TerrPlant (v1.2.1) screening model. TerrPlant estimates potential exposure fiom a single application using default assumptions for runoff and spray drift (Table 10). See APPENDIX E for more information.

TABLE 9. EECs on Potential Food Items Following Label-Specified Applications (0.045 Ibs a.i./Acre) of Pyrasulfotole Using the T-REX Model (ppm).

C. Ecological Effects Characterization DIETARY-BASED EECS

Short Grass Tall Grass Broadleaf Plants/Small Insects FruitslPodslSeedslLar~e Insects

TABLE 10. EECs on Plants Following Label-Specified Applications (0.045 Ibs a.i./Acre) of Pyrasulfotole Using the TerrPlant Model (Ibs a.i./A).

APPENDIX F lists the ecological effect studies considered for this assessment (i.e., studies submitted by the registrant). Citations for all ofthe ECOTOX references identified for pyrasulfotole are found in APPENDIX A. All ofthe studies identified 

### by ECOTOX failed the ECOTOX screening, and were rejected because they were in a foreign language. Therefore, all ofthe toxicity endpoints used here are from registrantsubmitted studies. RATE

0.045 lbs ai/A

Based on the available data, pyrasulfotole is practically nontoxic to fish and fi-eshwater invertebrates, slightly toxic to freshwater nonvascular plants, moderately toxic to estuarine/marine nonvascular plants, highly toxic to estuarine/marine invertebrates, and very highly toxic freshwater vascular plants. Chronic exposure resulted in reduced growth in fish and reduced survival in freshwater aquatic invertebrates. Pyrasulfotole is practically nontoxic to birds and mammals on an acute oral exposure basis. Chronic exposure resulted in reduced male weight gain in birds and delayed maturation and corneal opacity in mammals. Monocots were the least sensitive group of terrestrial plants tested in both seedling emergence and vegetative vigor studies. See Table 11 for the assessment endpoints considered in this assessment. KENAGA VALUES Upper Bound 10.8 4.95 6.08 0.68

'Loading is runoff plus drift (Ibs ai1A) APPLICATION METHOD

Ground Aerial Mean 3.83 1.62 2.03 0.32

ADJACENT

UPLAND LOADJNG' 0.0027 0.0045 ADJACENT WETLAND LOADING 0.0230 0.0248 DRIFT ONLY

0.0005 0.0023

### TABLE 11. 

### Summary of Specific Assessment Endpoints for Animals and Plants Considered in this Assessment. TAXA 

### I MEASURE OF EFFECT

Freshwater Invertebrates Survival, growth and/ 

### I Species 

### I Toxicity

or reproduction of: Freshwater Fish

Fish Endpoint

EstuarineNarine Invertebrates Acute

Aquatic Plants Oncorhychus mykiss Rainbow trout Chronic Pimephalespromelas Fathead minnow Acute Daphnia magna ( ECso =>95.8 mg/~' 

## I Mortality LCso= >96 mg/~' Mortality

Chronic Daphnia magna ] NOAEC = 12.8 mg a.i./L 

## I Mortality Acute

Chronic Not Available 

## I Not Available ( NIA Cyprinodon variegates Sheepshead minnow Chronic Not Available 

## I Not Available 

## I N/A Acute NOAEC = 0.58 mg a.i./L

Americamysis buhiu Mysid

Listed Lemna gibba 

## I NOAEC = 9.57 pg a.i./L 

## I Reduction in frond dry Reduction in total length

LCso= >lo0mg./~'

Acute Mortality

LC50 = 1.1 mg1L

Lemna gibba Duckweed

algae Mortality

Duckweed EC50= 28 pg a.i./L



## I weight Reduction in frond dry weight

Acute Acute

Skeletonemu costatum Marine diatom Listed Pseudokirchneriella subcapitata Freshwater algae

Skeletonemu costaturn Marine diatom Acute ECso= 8.3mg a.i./L

Colinus virginianus Northern bobwhite quail

Anusplatyrhynchos Mallard duck Chronic Anus platyrhynchos Mallard duck ECSo= 11mg a.i./L

Reduction in biomass

NOAEC = 2.53 mg a.i./L Reduction in cell density and biomass

Reduction in biomass

LC50= >4,9 11mg/kg-diet' LDsO =>2,000 mg/kg-bw'

LCs0= >5,089 mg/kg-diet' Reduction in cell density, growth rate, and biomass Listed

Mortality

NOAEC = 167 mg a.i./kgdiet Pseudokirchneriellu subcapitata Freshwater

Decreased male body weight gain NOAEC = 2.6 mg a.i./LTAXA Survival, growth and/

or reproduction of: Mammals

Terrestrial Invertebrates

Terrestrial Plants

This endpoint used to MEASURE OF EFFECT Species Toxicity Endpoint

Acute Wistar rat LDso= >2,000 mg a.i.lkg- Mortality bw' Chronic Wistar rat NOAEL = 2.5 mg a.i.1kg- Delayed balano-preputial bw separation (an indicator of the onset ofpuberty) in FI pups and diffuse and reticulate corneal opacity in both generations Acute Apis mellifera LDsO = >75 pgibee Mortality Honey Bee (contact)' Acute (Seedling Emergence) Monocot: NIA 

## I EC25 = >0.0249 lb ailacre ( NIA Dicot: Tomato 

## I EC25 = 0.001 1 lb a.i.1A 

## I Decreased dry weight Listed (Seedling Emergence) Monocot: NIA 

### I NOAEC = 0.0249 lb 

### I NIA a.i./acre Dicot: Tomato NOAEC = 0.000399 lb Decreased dry weight a.i.1A

Dicot: Tomato 

### 1 EC2S= 0.00081 lb a.i.1A 

### I Decreased dry weight

- - Listed (Vegetative vigor) Monocot: Onion 

## I NOAEC = 0.0125 lbs a.i.1A 

## I Decreased dryweight Dicot: Tomato 

## I EC05 = 0.000797 Ib a.i.1A ( Decreased dry weight lculate RQs in the 'Risk Description' section of this assessment.1. Aquatic Effects Characterization
a. Aquatic Animals
Studies were submitted for three freshwater fish [rainbow trout (Oncorhychus mykiss), bluegill sunfish (Lepmismacrochirus), and fathead minnow (Pimephalespromelas)], one freshwater invertebrate (Daphnia magna), one estuarinelrnarine fish [sheepshead minnow (Cyprinodon variegates)], one estuarinelrnarine mollusk [Eastern oyster (Crassostrea virginica)], and one estuarinelmarine crustacean [mysid shrimp (Americamysis bahia)], all exposed to technical grade pyrasulfotole.
Acute toxicity tests for Daphnia (MRID: 46801 7-21), sheepshead minnow (MRID: 468017-26), mollusk (MRID: 46801 7-22), rainbow trout (MRID: 468017-24) and bluegill sunfish (MRID: 46801 7-25) all resulted in no effects, including sublethal effects, to the species at the highest treatment level tested. The mysid study (MRID: 46801 7-23) resulted in an ECsoof 1.1mg a.i./L. At the 24-hour observation interval, lethargy was observed in the mean-measured 1.5,2.9 and 6.2 mg ailL treatment levels and erratic swimming was observed in the mean-measured 6.2 and 12mg ai/L treatment levels. At the 48-hour observation interval, onemysid in the mean-measured 1.5mg ai/L treatment level was lethargic and on the bottom ofthe test vessel, several mysids were lethargic in the mean-measured 6.2mg ai/L treatment level and all surviving mysids in the meanmeasured 12mg ai1L treatment level were swimming erratically. At 72- and 96-hours, no sub-lethal effects were observed in the control or any ofthe treatment levels. Therefore, for acute effects, the following endpoints will be used to assess the risk of pyrasulfotole to aquatic animals: freshwater fish

-LCso=>96 mg a.i./L; freshwater invertebrate - EC50 = >95.8 mg a.i.1L; estuarinelmarine fish - LC50 =>I00mg a.i./L; and estuarinelrnarine invertebrate - ECso= 1.1mg a.i./L.

A chronic test for Daphnia resulted in a 21-day NOAEC of 12.8mg a.i./L (MRID: 46801 7-27), based on reduced survivallimmobility (and other clinical signs of toxicity). A freshwater fish early life-stagelreproductive study on fathead minnow resulted in a NOAEC of 0.58 mg a.i.1L (MRID: 468017-27). The most sensitive endpoint for this 35- day test was a reduction in total length. Therefore, for chronic effects, a NOAEC of 12.8 mg a.i./L and a NOAEC of 0.58 mg a.i./L will be used to assess the risk ofpyrasulfotole to freshwater invertebrates and freshwater fish, respectively.

Based on these submitted studies, pyrasulfotole is classified as practically nontoxic to fish and freshwater invertebrates but is highly toxic to estuarinelmarine invertebrates on

an acute exposure basis. There were no mortality or sublethal effects at the highest treatment levels tested in most of the acute studies (i.e., all ofthe LC50 or ECSO endpoints are 'greater than' values except for the EC50value for the mysid). These 'greater than' endpoints were not used to calculate RQ values here; however, they are used to help characterize the risk in the 'Risk Description' section of this assessment.b. Aquatic Plants

Studies were submitted for a freshwater vascular plant [duckweed (Lemna gibba)],bluegreen algae (AnabaenaJlos-aquae), a freshwater diatom (Navicula pelliculosa), a green algae (Pseudokirchneriella subcapitata formerly known as Selenastrum capricornutum), and a marine alga (Skeletonema costatum) exposed to technical grade pyrasulfotole.
Pyrasulfotole is very highly toxic to duckweed based on reductions in frond dry weight in

a 7-day toxicity study (MRID: 46801 7-36). In this study an ECsovalue of 28 pg a.i./L was reported; the associated NOAEC was 9.57 pg a.i./L. Therefore, an ECS0 value of 28 pg a.i./L and a NOAEC of 9.57 pg a.i./L will be used to assess the risk of pyrasulfotole to aquaticmacrophytes.
Acute toxicity tests in freshwater nonvascular plants resulted in 96-hour EC50values ranging from 11mg a.i./L for reductions in cell density and biomass in green algae (MRID: 46801 7-37) to 53 mg a.i./L based on reductions in biomass in freshwater diatoms (MRID: 468017-38). The lowest EC50value of 11mg a.i./Lbased on decreased cell density and biomass and the associated NOAEC of2.6 mg a.i./L for reductions in cell density, growth rate, and biomass in Pseudokirchneriella subcapitata will be used to

assess the risk ofpyrasulfotole to freshwater nonvascular plants.

An acute (96-hour) toxicity test with a marine diatom resulted in 

### an ECsovalue of 8.3 mg a.i./L based on a reduction in biomass in Skeletonema costatum (MRID: 468017-40). The ECsovalue of 8.3 mg a.i./L and the associated NOAEC of 2.53 mg a.i./L for reductions in biomass in Skeletonema costatum will be used to help assess the risk of pyrasulfotole to marine plants.

Based on the data, pyrasulfotole is classified as very highly toxic to vascular aquatic plants, slightly toxic to freshwater nonvascular plants, and moderately toxic to marine plants on an acute exposure basis.



### 2. Terrestrial Effects Characterization

a. Terrestrial Animals



### Birds

Based on the LD50value for the northern bobwhite quail (Colinus virginianus) of >2,000 mglkg-bw, pyrasulfotole is characterized as "practically nontoxic" to avian species on an acute oral-exposure basis (MRID: 46801 7-29). Pyrasulfotole is "practically nontoxic" to "slightly toxic" to avian species on a subacute dietary-exposure basis, with the lowest of >4,911 mglkg-diet reported for northern bobwhite quail (MRID: 46801 7-30). The LCs0for the mallard duck (Anasplatyrhychos) is >5,089 mg a.i./kgdiet (MRID: 46017-31). In this assessment, an value of >4,911 mglkg-diet and an LDSo of >2,000 mgkg-bw will be used to assess the risk ofpyrasulfotole to birds. In all ofthe avian acutetoxicity studies submitted, there were no mortality or sublethal effects at thehighest treatment levels tested (i.e., all ofthe LDS0 and LCsoendpoints are 'greater than' values), therefore, these endpoints are not used to calculate 

### RQ values here. They are, however, used to help characterize risk in the 'Risk Description' section ofthis assessment.
Avian reproduction studies were performed for pyrasulfotole in two species, mallard duck and northern bobwhite quail. The lowest LOAEC was for the mallard duck (557 mg/kg-diet) based on decreased male body weight gain at thehighest treatment level (MRID: 46801 7-33). The lowest NOAEC was also for the mallard duck (167 mg a.i./kg diet) (MRID: 468017-33). In the northern bobwhite quail study there were slight, but statistically significant, reductions (3 -

### 9%) in ratios of eggs set to eggs laid, number hatched to eggs laid, number hatched to live 3-week embryos, and hatchling weights at the highest treatment level which resulted in a LOAEC and NOAEC of 594 mg a.i./kg diet and 205 mg a.i./kg diet, respectively. For the purposes ofthis risk assessment, 167 mgkg-diet serves as the toxicological endpoint for evaluating chronic effects in birds.

Mammals

Based on the LDS0 value for the Wistar rat of >2,000 mgtkg-bw, pyrasulfotole is characterized as "practically nontoxic" to mammalian species on an acute oral-exposure basis (MRID: 46801836). In the acute oral study, involving a single doselanimal and a 14-dayobservation period, there were no mortalities at any ofthe treatment levels. Additionally, there were no indications of neurotoxic effects or effects on body weight gain or food consumption at any treatment level. There were, however, increased incidents of corneal opacity and corneal neovascularization in females and retinal degeneration in males at the 500 mglkg-bw treatment level. The corneal effects are believed to be the result of increased tyrosinemia from HPPDase inhibition (the biochemical mechanism of action of pyrasulfotole). Because there were no mortalities at the highest treatment levels tested (i.e., the LDsoendpoint is a 'greater than' value), this endpoint (>2,000mgkg-bw ) is not used to calculate RQ values here. It is, however, used to help characterize risk in the 'Risk Description' section of this assessment.

In a two generation reproductive toxicity study with the Wistar rat (MRID: 46801907), the reproductive NOAEL was 2.5 mg/kgbwlday based on delays ofbalano-preputial separation (an indicator ofthe onset ofpuberty) in 

### Flmales at the LOAEL of 26.3 mg/kg bwlday. In a neurotoxicity studyin the Wistar rat (MRID: 4680 1917),the NOAEL was 3.8 mglkg-bwlday based on ocular opacities in dams at 

### 237 mg/kg-bwlday; and decreased postnatal weights, delayed preputial separation, decreased brain weights and retinal degeneration in offspring at the highest treatment levels (237 mglkg-bwlday). For the purposes of this risk assessment, a NOAEL of 2.5 mg/kg-bwlday serves as the toxicological endpoint for evaluating chronic effects in mammals.

Terrestrial Invertebrates

The registrant submitted one guideline (acute honey bee-contact) and two non-guideline (acute honey bee-oral and acute earthworm) terrestrial invertebrate toxicity studies forpyrasulfotole. These studies resulted in the following: a honey bee oral LDsoof>I20 pg a.i./bee (MRID: 468017-34); a honeybee contact LD50 of>75 pg a.i./bee (MRID: 468017-35); and 

### an EC50and NOAEC of >1,000 mg a.i./kg for earthworms (MRID: 4680 17-41). Therefore, pyrasulfotole is classified as 'practically nontoxic' to non-target terrestrial insects on an acute oral and contact exposure basis. In all ofthe terrestrial invertebrate studies there was no mortality or sublethal effects at the highest treatment levels tested 

### (i.e.,all of the LD5~ and ECsoendpoints are 'greater than' values).

b. TerrestrialPlants

The effects ofthe proposed North American pyrasulfotole formulations, AE 0317309

### + Bromo Herbicide (3.3% pyrasulfotole, 13.4% bromoxynil octanoate, and 12.9% bromoxynil heptanoate) and AE 03 17309 SE06 Herbicide (4.4% pyrasulfotole), were tested on various monocots and dicots in Tier I1 seedling emergence and vegetative vigor studies.

Results ofthe Tier I1 seedling emergence studies with the AE 03 1730902 SE06 and AE 0317309

### +Bromo formulations showed no measurable effects to monocots at any ofthe tested treatment levels [thehighest treatment levels for monocots were 0.0249 to 0.0994 Ibs a.i./acre -depending on the species

-for the AE 03 17309 02 SE06 formulation, and 0.029 Ibs a.i.(pyrasulfotole only)/acre for the AE 03 17309

## + Bromo formulation]. For dicots, tomato was the most sensitive species in the seedling emergence studies for both formulations, with decreased 

### dry weight as themost sensitive endpoint affected. The NOAEC and EC2Svalues were 0.000399 Ib a.i./A and 0.001 

### 1lb a.i./A, respectively, for tomato dry weight in the study with the AE 03 17309 02 SE06 formulation. In the seedling emergence study with the AE 03 17309

### + Bromo formulation, the NOAEC and EC2swere 0.00022 lb a.i.(pyrasulfotole only)/A and 0.00025 lb a.i. (pyrasilfotole only)/A, respectively. Although the AE 03 17309

### + Bromo formulation is more toxic to dicots than the AE 03 17309 02 SE06 formulation based on the seedling emergence studies, the results fiom the SE06 formulation are used to calculate RQs since the AE 03 17309

### + Bromo formulation includes other active ingredients. Because AE 03 17309

### + Bromo formulation is a mixture of different active ingredients, the results from the studies using this formulation cannot be used to specifically assess the risks of pyrasulfotole to plants. Results fiom the AE 0317309

### +Bromo formulation, however, are incorporated into the Risk Description section of this assessment. Therefore, a NOAEC of 0.00039 lb a.i./A and an ECZ5 of 0.001 1lb a.i./A are used to assess the effects of exposure to pyrasulfotole on seedling emergence in non-listed and listed terrestrial plants (see Table 

### 12).

Results ofthe Tier I1 vegetative vigor studies identify onion as the most sensitive monocot with decreased dry weight as the most sensitive endpoint affected (with the AE 03 17309 02 SE06 formulation). TheNOAEC and EC2S values for onion dry weight were 0.0125 Ibs a.i./A and 0.017 lbs a.i./A, respectively. No effects were seen in monocots in the vegetative vigor study with the AE 03 17309

### + Bromo formulation [thehighest treatment level tested was 0.030 lbs a.i. (pyrasulfotole only)/acre]. For dicots, tomato

was the most sensitive species with the AE 03 17309 02 SE06 formulation (NOAEC =0.000797 lb a.i./A; EC25 = 0.00081 lb a.i./A for dry weight), while cucumber was the most sensitive dicot with the AE 03 17309

### + Bromo formulation [NOAEC <0.00012 Ib a.i. (pyrasulfotole only)/A; EC25 = 0.00017 lb a.i. (pyrasulfotole only)/A for dry weight]. Therefore, a NOAEC of 0.0125 lbs a.i./A and an EC25of 0.017 lbs a.i./A, for onion dry weight, areused to assess the effects of exposure to pyrasulfotole on vegetative vigor in
monocot plants.

For dicots, although the AE 03 17309

### + Bromo formulation is more toxic than the AE 0317309 02 SE06 formulation based onthe vegetative vigor studies, the results from the SE06 formulation are used to calculate RQs since the AE 03 17309

### + Bromo formulation includes other active ingredients. Results from the AE 03 17309

### + Bromo formulation are incorporated into the Risk Description section ofthis assessment. Therefore, a NOAEC of 0.0.000797 lb a.i./A and an ECz5of 0.00081 lb a.i./A (based on tomato dry weight) are used to assess the effects of exposure to pyrasulfotole on vegetative vigor in non-listed and listed terrestrial dicots (see Table 12).

TABLE 12. Terrestrial Monocot and Dicot Endpoints (Ibs a.i./acre) from the Pyrasulfotole SeedlingEmergence and Vegetative Vigor Studies. SEEDLING EMERGENCE 

## I VEGETATIVE VIGOR AE 0317309 02 

## 1 AE 0317309

### + 

## I AE 0317309 02 

## 1 AE 0317309

### + SE06Formulation (Max. Application

Rate =0.045 Ib a.i./acre) only)/acre] ECts 

## 1 Monocots 

## I > 0.0249" 

## I > 0.029



### * The most sensitive endpoint I These represent the highest concentrations tested.

The NOAEC for the most sensitive species is below the lowest tested concentrations (<0.00012 lbs a.i./A), therefore, this number is the ECoS value. Bolded nimbers are used to calculate RQs in this assessment. Bromo Formulation

[Max. Application Rate =0.037 Ib a.i. (pyrasulfotole

NOAEC

3. Toxicity of the Degradate Pyrasulfotole-Benzoic Acid 0.017"

Onemajor degradate, pyrasulfotole-benzoic acid (RPA 203328, AE 197555),was detected in the aerobic soil metabolism and terrestrial field dissipation studies. The toxicity data for RPA 203328 indicate that this degradate is less toxic (or at least not

more toxic, in the case of limit tests) to fish, aquatic invertebrates, aquatic vascular plants, birds, earthworms, and terrestrial plants, and is equitoxic to freshwater algae when compared to the parent chemical on an acute exposure basis (see Table 

### 13). No comparative chronic toxicity data are available for any taxa. There are no data to indicate that RPA 203328 is oftoxicological concern (which is in agreement with HED), and, therefore, it will not be included in this assessment. SE06 Formulation (Max.Application

Rate =0.045 lb ailacre) only)/acre]

> 0.030 Dicots Monocots Dicots Bromo Formulation [Max. Application Rate =0.037 lb a.i. (pyrasulfotole

0.0011 0.0249"'

## '
0.000399 0.00025* 0.029 0.00022* 0.00081 0.0125" 0.000797 0.00017* 0.030' 0.000016*3LTABLE 13. RPA 203328 Acute Toxicity Data for aVariety ofAnimals and Plants. SPECIES 

## I ENDPOINT 

## I DURATION ( MRID 

### I CLASSIFICATION 

## I COMMENTS 

# I

I Animals

virginianus Earthworms

Eisenia foetida Earthworms

Eisenia

, foetida

Freshwater green algae Selenastrum Rainbow trout Oncorhynchus mykiss Mysid Mysidopsis bahia Daphnid Daphnia

magna Northern bobwhite

quail

capricornutum

Duckweed

IV. Risk Characterization ECso= >1000 mg a.i.1kg

ECS0 = >I000 mg a.i.1kg

ECS0 = 5.9 ppm a.i. NOAEC = 2.4

Lemna gibba Various species; Vegetative Vigor

Various species; Seedling Emergence

A. Risk Estimation 

## - Integration of Exposure and Effects Data Olinus I I I I I LC5,,= 160 ppm a.i.

= 145 ppm a.i.

EC5,,= >I50 mg a.i./L

LCSo> 5265 ppm a.i.

ppm a.i. ECSo = >9.8

Toxicity data and exposure estimates are used to evaluate the potential for adverse ecological effects on non-target species. For this screening-level assessment of pyrasulfotole, the deterministic risk quotient method is used to provide a metric of potential risks. The RQ is a comparison of exposure estimates to toxicity endpoints; estimated exposure concentrations are divided by acute and chronic toxicity values. The 14 days

56 days

120 hrs

ppm a.i. Monocot: NIA Dicot: NIA

Monocot: NIA Dicot: NIA 96 hrs

96 hrs

48 hrs

8 days

14 days 4680 17-42

468017-43

Plants

439048-26

14 days

14 days 439048-25

447188-01

435732-4 1

446935-0 1

443999-10 Supplemental

Supplemental

Acceptable

443999-06

443999-07 Acceptable

Acceptable

Acceptable

Acceptable

Non-guideline; NOAEC = 556 mg a.i.1kg Non-guideline; NOAEC =2 1000 mg a.i.lkg

NOAEC = 2.4 ppm a.i.

Acceptable Flow-through; NOAEC = 130

Static; NOAEC = 25 ppm a.i. Flow-through test; NOAEC = 150mg a.i.1L NOAEC = 5265ppm a.i.

NOAEC = 9.8

Acceptable

Acceptable ppm a.i. Limit test - NOAEC 0.13 lbs a.i.1acre (highest level tested) Limit test - NOAEC 0.14 Ibs a.i./acre (highest levelresulting unitless RQs are compared to the Agency's levels of concern (LOCs) (see 

### Table 14), which are the Agency's interpretive policy such that when LOCs are exceeded, the need for regulatory action may be considered. These criteria areused to indicate when the use of a pesticide, as directed on the label, has the potential to cause adverse effects on non-target organisms.TABLE 

### 14. Agency Levels of Concern (LOC).
I I I 1 Risk

- -

Acute

Acute Restricted Use

Acute Listed Species

Chronic Description

Potential for acute risk to non-target organisms which may warrant regulatory action in addition to restricted use classification
Potential for acute risk to non-target organisms, but may be mitigated through restricted use classification RQ
acute RQ >0.5

Listed species may be potentially affected by

use

Non-Listed and Listed Plant Taxa
aquatic animals, mammals, birds

acute RQ > 0.1

acute RQ > 0.2

Potential for chronic risk may warrant regulatory action, listed species may potentially be affected through chronic exposure aquatic animals

mammals and birds

I acute RQ >0.05

acute RQ >0.1

1. Non-target Aquatic Animals and Plants aquatic animals

mammals and birds

chronic RQ > 1

Potential for effects in non-listed and listed plants

Table 15 lists the RQs calculated for aquatic animals for exposure to pyrasulfotole, based

on the EECs from 

### PRZM modeling scenarios. Pyrasulfotole is classified as 'practically nontoxic' to fish and freshwater invertebrates on an acute exposure basis. The only acute RQ we calculated for aquatic animals was for estuarinelrnarine invertebrates, since all other aquatic animals showed no effects as the highest treatment levels tested. Pyrasulfotole is classified as 'highly toxic' to estuarinelrnarine invertebrates, however, the acute RQs for estuarinelmarine invertebrates range from 0.006 (for the ORWheat scenario) to 0.009 (for the 

### TX Wheat scenario). Therefore, no RQs for aquatic animals exceed the Agency's LOC for acute risk. all animals

Thehighest calculated chronic exposure RQ for aquatic animals is 0.017 (rainbow trout), and isbelow the Agency's LOC for chronic exposure to animals. However, there are no chronic toxicity data available for estuarinelmarine invertebrates, which are the most sensitive of all ofthe aquatic animals tested. Estuarinelmarine invertebrates (ECSo = 1.1 mg a.i.1L) are more than 87 times (95.811.l)more sensitive to pyrasulfotole on an acute exposurebasis than freshwater invertebrates (EC50>95.8 mg a.i./L). Using an acute to chronic ratio and comparing the daphnid and mysid data results in a NOAEC for mysids of < 0.147 mg a.i./L [(95.8112.8) = 7.8; 1.117.8 = 0.1471. To trigger the Agency's chronic LOC, however, the estuarinelrnarine invertebrate NOAEC would need to be at least 9.9 pg a.i./L (using the 21-day peak value 

### from the

### TX Wheat scenario and an LOC of 1). In other words, estuarinelrnarine invertebrates would need to be at least 1,293 times more sensitive to pyrasulfotole than freshwater invertebrates [NOAEC - 12.8mg a.i.1L; (12.8 mg a.i.lL)1(0.0099mg a.i./L) = 1,2931on a chronic exposure basis to exceed the Agency's chronic LOC for listed and non-listed species. RQ> 1 all plantsTABLE 15. Aquatic Animal 

### RQ Values for Exposure to Pyrasulfotole.

Pyrasulfotole is classified as 'slightly toxic' to freshwater algae, 'moderately toxic' to marine diatoms, and 'very highly toxic' to aquatic vascular plants on an acute exposure basis. The Agency's 

### LOC for listed plants is exceeded for aquatic vascular plants (RQ = 1.045)with the 

### TX Wheat scenario. All other aquatic plant RQs are below the Agency's level of concern (Table 16). TAXA

EstuarineiMarine Invertebrates

Freshwater Fish

Freshwater Invertebrates

2. Non-target Terrestrial Animals EXPoSURE

Acute

Chronic

Chronic

TABLE 16. Aquatic Plant 

### RQ Values for Exposure to Pyrasulfotole.

Birds CALCULATED R ND Wheat 

# ! OR Wheat TXWbeat 

# 1

Pyrasulfotole is classified as 'practically nontoxic' to birds on an acute and sub-acute exposure basis. The RQs calculated for chronic exposure range from 0 to 0.06 using upper 90'" percentile Kenaga values (see Table 17). Therefore, none ofthe avian RQs calculated for chronic exposure exceed the Agency 

### LOC. 0.007

0.013

<0.001

TAXA

Bolded numbers indicate RQs that exceed the Agency's LOC for aquatic plants CALCULATED RQ

Aquatic vascular plants Freshwater algae

Marine diatom

Mammals 0.006

0.011

< 0.001

ND wheat 0.275 0.805

<0.001 0.003

< 0.001 0.003 Non-Listed Listed Non-Listed Listed Non-Listed Listed

TABLE 17. Avian 

### RQ Values for Chronic Exposure to Pyrasulfotole.

Pyrasulfotole is classified as 'practically nontoxic' to mammals on an acute oral exposure basis. The RQs calculated for chronic exposure range from 0.01to 0.22for dietary 0.009

0.017

<0.001

DIETARY CATEGORY

Short Grass Tall Grass BroadleafPlantslSmallInsects Fruits/Pods/Seeds/LargeInsects OR wheat 0.232 0.679

< 0.001 0.003

<0.001 0.002

RQ Upper 90th Percentile Kenaga 0.06 0.03 0.04 0.00 TX wheat 0.357 1.045

< 0.001 0.004 0.001 0.004exposure and 0.01 to 1.87for dose-based RQs using upper 9oth percentile Kenaga values (see Table 

### 18). The RQs for three body-sizeldietary categories exceed the Agency's LOC for chronic exposure: 15 g and 35 g mammals that eat short grass (RQs = 1.87 and 1.6, respectively) and 15 g mammals that eat broadleaf plants/small insects (RQ = 1.05).

TABLE 

### 18. Mammalian RQ Values for Chronic Exposure to Pyrasulfotole. Upper 90th Percentile Kenaga

DIETARY CATEGORY Short Grass

Tall Grass

BroadleafPlantsISmaU Insects

Fruits/Pods/Seeds/Large Insects

Terrestrial Invertebrates BODY SIZE 15 g 35 g 1,000g

15 g 35 g 1,000 p

15 g

Granivore

Pyrasulfotole is classified as 'practically nontoxic' to non-target terrestrial insects on an acute exposurebasis. Potential risk to terrestrial invertebrates from chronic exposure to pyrasulfotole could not be assessed dueto a lack of data. Screening-level risk assessments do not typically evaluate risks to terrestrial invertebrates; however, toxicity information for beneficial insects is used to develop precautionary label language where necessary. Based on the available data, precautionary label language for bees does not appear necessary. 35 g 1,000 g

15 g

35 g

3. Non-target Terrestrial and Semi-aquatic Plants DIETARY-BASED RQ 0.22

0.10

0.12

Bolded numbers indicate RQs that exceed the Agency's chronic risk LOC for mammals 1,000 g

15 g 35 g 1,000 g

Table 19 lists the terrestrial and semi-aquatic plant RQs for the maximum proposed application rate for pyrasulfotole based on results from the TerrPlant v. 1.2.1. Based on this analysis, none ofthe RQs for monocots, which range from 0.04 to 0.99, exceed the Agency's LOC of >l for plants. The RQs for semi-aquatic monocots for aerial and ground applications did approach the Agency's LOC for listed plants, and, therefore, the potential for risks to this taxon will be explored hrther in the 'Risk Description' section. DOSE-BASED RQ 1.87 1.60 0.86 0.86 0.73 0.39 1.05

0.01

All ofthe RQs for listed and nonlisted terrestrial and wetland dicots in areas adjacent to pyrasulfotole use sites do exceed the Agency's LOC. Additionally, the LOC is exceeded - 0.9 0.48 0.12

0.10

NIA 0.05 0.03 0.02 0.01for listed dicots based on drift alone for aerial applications. The RQs for nonlisted dicots based on ground applications range fkom 0.01 (drift only) to 20.86 (adjacent wetland), while those for aerial applications range from 0.06 (drift only) to 22.5 (adjacent wetland). For listed dicots, the RQs range from 0.56 (drift only) to 57.52 (adjacent wetland) for ground applications and 2.82 (drift only) to 62.03 (adjacent wetland) for aerial applications.

no EC25 value; could be determined firmonocots in the pyrasulfotole seedling emergence studies, only the results for the listed monocots are presented here.

Bolded numbers indicate RQs that exceed the Agency's LOC for plants. 

## 'Although this is below the Agency LOC of 1, it is close enough that we will consider it further. 

### TABLE 

### 19. RQ Values for Terrestrial and Semi-Aquatic Plants Exposed to Pyrasulfotole.

B. Risk Description TAXA

Nonlisted Species -Listed

Species

Theresults ofthis screening-level risk assessment indicate that the proposed uses of pyrasulfotole have the potential for direct adverse effects for listed freshwater vascular plants, listed and non-listed terrestrial and semi-aquatic dicotyledonous plants, and listed and non-listed mammals (chronic exposure). Therefore, thehypothesis from p. 14 [



### .. . the proposed agricultural uses ofpyrasulfotole have the potential to reduce survival, reproduction, and/orgrowth in terrestrial and aquatic animals and plants through spray dripand/or runoff]is supported. These results are based on a modeled spray application rate of 0.045 lbs a.i./A per year, which represents the proposed maximum application rate for cereal grains. Although direct adverse effects to non-mammalian animals (aquatic and terrestrial) from pyrasulfotole use are not expected, given the potential for effects on terrestrial and aquatic plant species and mammals, indirect effects to all animals are possible. Sinceplants are vital components ofmost habitats and ecosystems, alterations in the abundance ofplants or in the composition ofplant communities could result in adverse effects to non-plant species. Potential effects include, but are not limited to, reduction in food resources, decrease in cover (e.g.,for predator avoidance), change in water parameters (e.g.,increases or decreases in temperature and pH), and loss of breedingnesting habitat.
Reducing the proposed application rate from 0.045 lb a.i./acre to 0.040 lb a.i./acre results in an RQ of <l for listed aquatic vascular plants, and reducing the application rate to 0.023 lb a.i./acre results in chronic RQs of <l for all mammalian sizeldietary categories. Therefore, RQs for listed aquatic vascular plants and listed and non-listed mammals (from chronic exposure) could be reduced to below Agency LOCs ifthe maximum proposed application rate for pyrasulfotole was reduced to 0.04 lb a.i./acre and 0.023 lb

Both the 'Adjacent Upland' and 'Adjacent Wetland' values are based on seedling emergence data; since APPLICATION METHOD

Ground Aerial Ground Aerial ADJACENT UPLAND' Monocot NIA NIA 0.108 0.18 Dicot 2.45' 4.09 6.77 11.28 ADJACENT WETLAND' DRIFT ONLY

Monocot NIA NIA 0.92.~ 0.99" Monocot 0.03 0.13 0.04 0.18 Dicot 20.86 22.5 57.52 62.03 Dicot 0.01 0.06 0.56 2.82ailacre,respectively. Agency LOCs for listed and non-listed terrestrial and semi-aquatic dicotyledonous plants, however, are still exceeded at an application rate of 0.023 lb a.i./acre, indicating potential risks to dicots even at this rate.

1. Risks to Aquatic Organisms

a. Animals
No aquatic animal acute or chronic risk LOCs are exceeded for any of the proposed uses ofpyrasulfotole. The acute RQs for aquatic animals for estuarinelrnarine invertebrates ranged from 0.006 to 0.009, depending on the scenario modeled. The calculated RQ values for chronic exposure to pyrasulfotole ranged from <0.001 to 0.017 for all modeled use scenarios.

Because there was no mortality or sublethal effects at thehighest treatment levels tested in most ofthe acute aquatic animal studies submitted (with the exception of estuarinelmarine invertebrates), RQ values for acute exposure were not calculated for most aquatic animals in the Risk Characterization section ofthis assessment. In order to gain abetter understanding ofhow the EECs for the maximum proposed pyrasulfotole application rate relate to the toxicity data currently available for fish and aquatic invertebrates, RQ calculations were made using the highest level tested as the endpoint value, as a conservative assumption [i.e.,LC50= 100mg a.i./L (the actual highest concentrations tested in the aquatic animal studies ranged from 95.8 mg a.i./L to 104mg a.i./L)]. In this exercise all ofthe acute RQs calculated were less than 0.001 for all aquatic animals. The actual RQs would likely be much lower than these since no effects were actually identified at the 100mg a.i./L. Therefore, direct risk to aquatic animals from acute exposure to pyrasulfotole is unlikely.

None ofthe aquatic animal RQs for chronic exposure exceeded the Agency's LOC. Chronic toxicity data,however, are not available for themost acutely sensitive aquatic animal taxon (i.e., estuarinelmarine invertebrate). Even though pyrasulfotole is very soluble and moderately mobile to mobile based on the results ofbatch equilibrium studies, in aquatic systems (based on laboratory data) it does variably partition to the sediment and form unextractable residues and persist asparent. Additionally, there is

some evidence that pyrasulfotle may become less mobile as it it is exposedto viable microbs under certain conditions. Since PRZMIEXAMSmodeling requires one input for soil-water partitioning coefficient that is constant throughout the simulation (Kc= 122 ml/hcfor pyrasulfotole), the modeled partitioning to the sediment may be underestimated relative to the aerobic aquatic metabolism studies. Therefore, there is the potential for pyrasulfotole to accumulate in the benthos under certain conditions and to be a risk to benthic and epibenthic organisms (including some estuarinelmarine invertebrates). Although the chronic toxicity of pyrasulfotole to estuarinelmarine invertebrates is uncertain, given that: (1) the potential use sites for the proposed uses largely fall outside of estuarine/marine environments, with the possible exceptions of California and the midAtlantic states (see Figs. 

### 2,3, and 

### 4);(2) the aquatic EECs used in this assessment are based on a static water-body with no outlet, and, thus, are likely higher thanconcentrations expected in estuarinelmarine environments; and (3) estuarinelmarine invertebrates would need to be 1,293 times more sensitive to pyrasulfotole than freshwater invertebrates on a chronic-exposure basis to exceed the Agency's chronic risk LOC, risks to estuarinelmarine invertebrates from chronic exposure to pyrasulfotole are not expected.

Therefore, the likelihood of adverse effects on aquatic animals due to acute or chronic exposure to pyrasulfotole is considered low for the proposed uses based on the available toxicity data. Given the potential for effects onterrestrial and aquatic vascular plant species associated with the use ofpyrasulfotole, however, indirect effects on aquatic animals are possible.

b. Plants

Based on the predicted EECs for the modeled pyrasulfotole use and availabletoxicity data, the LOC for listed species is exceeded for vascular aquatic plants using the TX Wheat scenario 

### (RQ = 1.045). This indicates the potential for direct effects to listed aquatic vascular plants and indirect effects to listed species that rely on aquatic vascular plants for at least somepart oftheir life cycle (i.e., aquatic vascular plant species obligates). Reducing the proposed application rate from 0.045 Ib a.i./acre to 0.040 lb a.i./acre,however, results in apeak EEC of 8.9 ppb using the TX Wheat scenario. Therefore, at a maximum application rate of 0.040 lb a.i.lacre, risks to listed aquatic vascular plants are not expected.

There is no evidence ofpyrasulfotole degradation in aquatic environments. As such, pyrasulfotole was assumed stable inthe ecological pond used to estimate aquatic exposure concentrations. Since the ecological pond (used in our modeling) has no outlet, there was a modeled accumulation of pyrasulfotle in the pond throughout the 30year simulations. In the case ofpersistent compounds, a 1 -in-10 year EEC does not reflect varying meteorological conditions that are expected once every ten years, since the yearly peaks are not independent but are actually correlated to the previous year's peak concentration. This results in acute and chronic exposure concentrations that are very similar (i.e, < 2% difference between peak and 90-day average EECs). Estimated peak concentrations in the ecological pond are only high enough to result in an exceedance of the listed species LOC for vascular plants after 26 years of annual applications of pyrasulfotole assuming no dissipation whatsoever in the pond 

### (APPENDIX C). Pyrasulfotle concentrations in flowing water bodies are not expected to accumulate from year to year because of downstream dilution. Risk to aquatic plants resulting from accumulation ofpyrasulfotle from multiple years of application is not likely in flowing systems.2. Risks to Terrestrial Organisms

a. Animals

Birds

The avian chronic risk LOC (which is the same for listed and non-listed species) is not exceeded for any pyrasulfotole use indicating that the likelihood of adverse effects on birds due to chronic exposure is low. Because there was no mortality or sublethal effects at the highest treatment levels tested in the acute oral and sub-acute dietary avian studies submitted, standard RQ values for acute and sub-acute exposure were not calculated in the Risk Characterization section ofthis assesssment. In order to gain abetter understanding ofhow the EECs for the maximum proposed pyrasulfotole application rate relate to the toxicity data currently available for birds, we used T-REX to calculate RQs using the conservative assumption that the highest values tested in the avian studies represent endpoints (i.e., acute: LDso= 2,000 mg/kg-bw; sub-acute: LCsO =4,911 mglkg diet). In this exercise all of the acute and sub-acute RQs calculated using upper bound Kenaga values were between 0 and 0.01 for all size and dietary classes. The actual RQs would be much lower than these sinceno effects were actually identified at the 2,000 mag-bw and the 4,911 mglkg diet levels. Therefore, direct risk to birds from acute, sub-acute, or chronic exposure to pyrasulfotole is low. Given the potential for effects on terrestrial and aquatic plant species associated with the use of pyrasulfotole, however, indirect effects on birds are possible.



### Mammals
Because there was no mortality at the highest treatment levels tested in the acute oralexposure mammalian study submitted, standard RQ values for acute exposure were not calculated in the Risk Characterization section of this assessment. In order to gain a better understanding ofhow the EECs for the maximum proposed pyrasulfotole application rate relate to the toxicity data currently available for mammals, we used TREX to calculate RQs using the conservative assumption that the highest values tested in the avian studies represent endpoints (i.e., acute: LDsO =2,000 mglkg-bw). In this exercise all ofthe acuteRQs calculated using upper bound Kenaga values were 0 for all size and dietary classes. Using the the effect level of 500mgkg-bw in for increased incidents of corneal opacity and corneal neovascularization in females and retinal degeneration in males results in dose-based RQs from T-REX between 0 and 0.01 for all sizeldietary categories. Therefore, direct risk to mammals from acute exposure to pyrasulfotole is low.

The Agency's chronic risk LOC was exceeded for three body sizeldiet categories [I

### 5 g and 35 g mammals that eat short grass (RQs = 1.87 and 1.6, respectively) and 15g mammals that eat broadleaf plantslsmall insects (RQ = 1.05)],based on a reproductive NOAEL of 2.5mgkgbwlday. This NOAEL isbased on delays in maturation (specifically delayed balano-preputial separation) and diffuse and reticulate corneal opacity in pups (LOAEL =26.3 mgkgbwlday in males and 32.6 mgkg-bwlday infemales). Similar effects were seen in a 21-day Wistar rat developmental neurotoxicity study [NOAEL = 3.8 mgkg-bwldaybased on decreased food consumption during lactation and ocular opacities in dams; and decreased postnatal weights, delayed preputial separation, decreased brain weights and retinal degeneration in offspring at the highest treatment levels (37 and 354 mag-bwlday)]. A supplemental 24-month chronic toxicity study with Wistar rats failed to establish a NOAEC because of effects at the lowest treatment level (25 mgfkg-diet), including increased incidences of corneal opacity and neovascularization ofthe cornea.

It is unclear specifically how decreases in vision resulting from corneal opacity and retinal degeneration would affect the viability ofmammals. Additionally, some ofthe eye effects (specifically the corneal effects) observed in the rat studies are believed to be the result of increased tyrosinemia from HPPDase inhibition. Since different species are known to differ in their metabolism oftyrosine, it is unclear if rats are more susceptible to these eye abnormalities than other animals exposed to pyrasulfotole. For example, no eye disorders were observed in a submitted teratogenicity test in rabbits (MRID: 46801 906). The delayed maturation exhibited by the delays in balano-preputial separation, however, can be more clearly linked to potential adverse reproductive effects. Therefore, somemammals, specifically smaller-bodied (<35 g) mammals that eat short grass, broadleaf plants, or small insects, arepotentially at risk from chronic exposure to pyrasulfotole (based on the maximum proposed application rate for cereal grains).
Reducing the maximum application rate for pyrasulfotole to 0.023 lb a.i./acre results in chronic RQs of <l for all mammalian sizeldietary categories. Based on T-REX,the highest RQ for effects to mammals from chronic exposure to pyrasulfotole is 0.96 for 15g mammals that eat short grass (see APPENDIX D). Therefore, potential risks to listed and non-listed mammals (from chronic exposure to pyrasulfotole) are not expected at application rates 50.023 lb a.i./acre.

Terrestrial Invertebrates

EFED does not currently estimate risk quotients for terrestrial non-target invertebrates. However, a label statement isrequired to protect foraginghoneybees when the LDS0 is < 11 pghee. Based on the acute contact toxicity studyto honeybees, the LDso for pyrasulfotole is >75 pghee. This classifies pyrasulfotole aspractically non-toxic to honeybees on an acute contact exposure basis. Additionally, in all ofthe terrestrial invertebrate studies there was no mortality or sublethal effects in any ofthe treatment levels tested. Therefore, the risk for direct adverse effects to terrestrial invertebrates is considered low; however, due to the risk to plants, the potential for indirect effects to terrestrial invertebrates from pyrasulfotole use cannot be discounted.

b. Plants

Tier I1plant studies demonstrate the potential for pyrasulfotole to affect terrestrial dicot plants. In the vegetative vigor studies, the exposure levels equivalent to a 25% effect level were 0.017 lbs a.i./A for monocots and 0.00081 lbs a.i./A for dicots, based on thestudy with the AE 03 17309 SE06 formulation. Results from the seedling emergence study indicated that a 

### 25% effect level was 0.001 1Ibs a.i./a for dicots (no effects were seen in monocots). None ofthe RQs for monocots, which range from 0.03 to 0.99, exceed the Agency's LOC of>l for plants. However, the RQs for semi-aquatic monocots approached the Agency's LOC of 1 for listed species (RQs = 0.92 and 0.99 for ground and aerial applications, respectively). These RQs were calculated based on the NOAEC for ryegrass which showed no effects at the highest treatment level tested (0.0249 Ib a.i./acre; approximately half ofthe proposed maximum application rate) in a seedling emergence study. Therefore, the actual no effect level would likely be higher, which would result in a lower RQ. Furthermore, pyrasulfotole showed no adverse effects

on the other monocot species tested in the seedling emergence studies at rates up to 0.10 lbs a.i./acre (more than twice the proposed maximum application rate). Therefore, the potential risk to listed semi-aquatic monocot species is considered low.

All ofthe RQs for listed and nonlisted terrestrial and wetland dicots in areas adjacent to pyrasulfotole use sites do exceed the Agency's LOC. Additionally, the LOC is exceeded for the RQ for listed dicots based on drift alone for aerial applications.

Regarding the AE 0317309

### + Bromo formulation [which contains three active ingredients: 3.3% pyrasulfotole, 13.4% bromoxynil octanoate, and 12.9%bromoxynil heptanoate], monocots are less sensitive and dicots aremore sensitivewhen compared to the AE 03 17309 SE06 formulation [which contains only one active ingredient: 4.4% pyrasulfotole]. Because AE 03 17309

### + Bromo formulation is a mixture of different active ingredients, the results from the studies using this formulation cannot be used to

assess the risks to plants from pyrasulfotole use specifically, although the results are reported as Ibs ofpyrasulfotole/acre. The results, however, can be used to help assess the risk ofthe formulated product to plants. Table 20 compares the RQs for dicots for the AE 0317309 SE06 and AE 03 17309

### + Bromo formulations based on TerrPlant v. 1.2.1. Sincemonocots are less sensitive to the AE 03 17309

### + Bromo formulation than to the AE 0317309 SE06 formulation, only the results for dicots arepresented below.

To gain a better understanding ofthe potential for spray

### drift to affect terrestrial dicots, AgDRIFT (v. 2.01) Tier 111 aerial modeling was used to determine how far off-field pyrasulfotole levels would remain above the EC25 for vegetative vigor of dicotyledonous plants. A~DRIFT~ utilizes empirical data to estimate off-site deposition of aerial and TABLE 20. Comparison of RQ Values for Terrestrial and Semi-Aquatic Dicots Exposed to the AE 0317309 SE06 and AE 0317309 

## +Bromo formulations. TAXA

Nonlisted Species Listed Species

Bolded numbers indicate RQs that exceedthe Agency's LOC for plants. APPLICATION METHOD

Ground Aerial Ground Aerial ADJACENT UPLAND AE 0317309 +Bromo 10.8 18 10.09 16.82 ADJACENT WETLAND AE 0317309

SE06 2.45' 4.09 6.77 11.28 AE 0317309

### +

Bromo

91.8

99 85.77 92.5 DRIFT ONLY

AE 0317309

SE06 20.86 22.5 57.52 62.03 AE 0317309 

### +

Bromo

2.65 13.24 23.13 115.63 AE 0317309

SE06 0.01 0.06 0.56 2.82ground applied pesticides. Details concerning the specifics and uncertainties of AgDRIFT are available online at www.agdrift.com. The default 'Maximum Downwind Distance' for AgDRIFT is 2,608 ft, however, this parameter canbe changed to 1 mile in Tier I11 modeling with the understanding that any calculations beyond 2,608 

### ft increases the uncertainty associated with the results. For the AE 03 17309 SE06 formulation, assuming the maximum single application rate of 0.045 lbs a.i./A, ASAE Fine to Medium droplet size distribution (an ASAE Medium droplet size distribution is stipulated on the label), 10mph winds, and 10ft application height, dicots 390 

### ft or closer to the treated use area may be exposed to pyrasulfotole levels above the EC25(0.001 1lbs a.i./acre) (for specific input parameters, see APPENDIX 

### G). If droplet size distribution was increased to ASAE Medium to Coarse, the distance from the treated site where spray drift might exceed the EC25is 203 ft. For the AE 03 17309

### + Bromo formulation, assuming the maximum single application rate of 0.037 lbs a.i. (pyrasulfotole only)/A, ASAE Fine to Medium droplet size distribution (an ASAE Medium droplet size distribution is stipulated on the label), 10mph winds, and 10

### ft application height, dicots 2,126 

### ft or closer to the treated use area may be exposed to pyrasulfotole levels above the EC25[0.00025 lbs a.i. (pyrasulfotole only)/acre]. For listed dicot species, these distances would be greater.

For ground applications (Tier I), high boom, ASAE Fine to MediumICoarse droplet size distribution, 9oth data percentile, dicots within 23 

### ft and 105

### ft to the treatment site (for the AE 03 17309 SE06 and AE 03 17309

### +Bromo formulation, respectively) are predicted to be exposed to pyrasulfotole levels above the EC25. Again, for listed dicot plant species, the distances would be greater.

Therefore, the potential for adverse effects ofpyrasulfotole use to listed and non-listed dicotyledonous plants extend well beyond the treatment site for both aerial and ground applications.

3. Review of Incident Data

There are no reports of ecological incidents for pyrasulfotole in the EIIS (Environmental Incident Information System) database. Because this is a new chemical that has not been registered for use in the United States, the existence of such incident reports would be unlikely.

4. Federally Threatened and Endangered (Listed) Species Concerns

a. Action Area
For listed species assessment purposes, the action area is considered to be the area affected directly or indirectly by the Federal action and not merely the immediate area involved in the action. At the initial screening-level,the risk assessment considers broadly described taxonomic groups and conservatively assumes that listed species within those broad groups are located on or adjacent to the treated site and aquatic organisms are assumed to be located in a surface waterbody adjacent to the treated site. The assessment also assumes that the listed species are located within an assumed areathat has the relatively highest potential exposure to the pesticide, and that exposures are likely to decrease with distance from the treatment area.

If the assumptions associated with the screening-level action area result in RQs that are below the listed species LOCs, a "no effect" determination conclusion is made with respect to listed species in that taxa, and no further refinement ofthe action area is necessary. Furthermore, RQs below the listed species LOCs for a given taxonomic group indicate no concern for indirect effects upon listed species that depend upon the taxonomic group covered by the RQ as a resource. However, in situations where the screening assumptions lead to RQs in excess ofthe listed species LOCs for a given taxonomic group, a potential for a "may affect" conclusion exists and may be associated with direct effects on listed species belonging to that taxonomic group or may extend to indirect effects upon listed species that depend upon that taxonomic group as a resource. In such cases, additional information on thebiology of listed species, the locations of these species, and the locations ofuse sites could be considered to determine the extent to which screening assumptions regarding an action area apply to a particular listed organism. These subsequent refinement steps could consider how this information would impact the action area for a particular listed organism and may potentially include areas of exposure that are downwind and downstream ofthe pesticide use site.

b. Taxonomic Groups Potentially at Risk

The Level 

### I screening assessment process for listed species uses the generic taxonomic group-based process to make inferences on direct effect concerns for listed species. The first iteration ofreporting the results ofthe Level I screening is a listing of pesticide use sites and taxonomic groups for which 

### RQ calculations reveal values that meet or exceed the listed species LOCs (for more inforrnation see, USEPA 2004).

(1). Discussion of Risk Quotients

None ofthe Agency's acute listed species LOCs or chronic listed species LOCs were exceeded for any group ofterrestrial or aquatic non-mammalian animal for any pyrasulfotole use. Additionally, the listed species LOC for plants was not exceeded for monocots or for any non-vascular aquatic plant. The Agency's listed species LOC, however, was exceeded for fieshwater vascular plants, the listed species and acute risk LOCs were exceeded for dicots, and the chronic risk (forlisted and non-listed species) was exceeded for some mammals at the maximum proposed application rate for pyrasulfotole. This indicates a potential risk for direct adverse effects to Federally-listed dicots, fieshwater vascular plants, and mammals and indirect adverse effects to any listed species that rely on these taxa as resources critical to their life cycle.

(2). Probit Dose Response Relationship
Although no acute LOCs were exceeded for any animal, indicating a low acute risk to these taxa, theprobit sloperesponse relationship can be used to calculate the chance of an individual event corresponding to the listed species acute LOCs and/or RQs. Theanalysis uses the 

### EFED spreadsheet IECvl

.1.xls. It is important to note that the IEC model output can go as high as 

### 1 x 1016or as low as 

### 1 x 10-l6 in estimating the event probability for animals. This cut-off is a limit in the Excel spreadsheet environment and is not to be interpreted as an agreed upon upper or lower bound threshold for concern for individual effects in any given listed species.

If information isunavailable to estimate a slope from a study, a default slope assumption of4.5 is used as per original Agency assumptions of typical slope cited in Urban and Cook (1986). Slopes were not available for the acute toxicity studies on freshwater fish, freshwater invertebrates, estuarinelrnarine fish, birds, mammals, and terrestrial invertebrates. Therefore, probit-dose analyses were donebased on the taxon-specific acute listed species LOCs and a default slope of4.5to estimate an individual effects probability for freshwater fish, freshwater invertebrates, estuarinelrnarine fish, birds, mammals, and terrestrial invertebrates. This resulted in a chance of 1in 418,000,000 for freshwater fish, freshwater invertebrates, estuarinelmarine fish, and terrestrial invertebrates, and 1 in 1in 294,000 for birds and mammals. To explore possible bounds to such an estimate, slopes of 2 and 9 were used to calculate upper and lower estimates of the effects probability associated with the listed species LOC. The chance ofindividual effects with these slopes ranged from 1 in 44 to 1 in 1 in 1.75E+1 for the various taxa (see

### Table 21).

The only animal taxonomic group for which a probit slope is available is estuarinelrnarine invertebrates [based on an ECsoof 1.1mg a.i./L for the mysid (Americamysis bahia) (MRID: 468017-23)]. Theprobit slope in this study was 2.23 with

a 95% confidence limit of 1.66 and 2.8. The corresponding estimated chance of individual mortality associated with a slope of 2.23 and the listed species LOC of 0.05 is 1in 538. To explorepossible bounds to such an estimate, the upper and lower 95% confidence limits for the probit slope estimate (1.66 and 2.8) were used to calculate upper and lower estimates ofthe effects probability associated with the listed species LOC. These values are 1 in 65 and 1in 7,420, respectively (see Table 21).

### TABLE 21. Chance of an Individual Effect Correspondingto the Listed Species

- Acute LOCs Using a Probit Slope Response Relationship. TAXA 

## I LOC 

### I PROBIT SLOPE 

### I CHANCE OF AN INDIVIDUAL 

### I 

## I EFFECT



### - Freshwater Invertebrates

- EstuarinemarineFish - Freshwater Fish 

### 1 0.05 

### 1 Slo~e 

### 1 4.5' 

### 1 1in 418.000.000
L 

# -

, ,

Upper Bound 

## 1 2 

## I 1in216 Lower Bound 

### 1 9 

### 1 1in 1.75E+31



### - Terrestrial ~nvertebrates'

- Estuarinemarine Invertebrates



## I 1in 8.86E+18 

## ' The Agency does not currentlyhave a listed-species LOC for terrestrial invertebrates;for our purposes 

### - Birds



### - Mammals

here, we use the aquatic invertebrateacute listed-speciesLOC (RQ > 0.05).

This is the deafault slope. 0.05

(3). Indirect Effects Analysis 0.1

The Agency acknowledges that pesticides have thepotential to exert indirect effects upon listed organisms by, for example, perturbing forage or prey availability, altering the extent ofnesting habitat, and creating gaps in the food chain. In conducting a screen for indirect effects, direct effect LOCs for each taxonomic group areused to make inferences concerning thepotential for indirect effects upon listed species that rely upon non-listed organisms in these taxonomic groups as resources critical to their life cycle. Slope Upper Bound

The Agency's listed species LOC was exceeded for freshwater vascular plants, the listed species and acute risk LOCs were exceeded for dicots, and the chronic risk LOC (for listed and non-listed species) was exceeded for some mammals 

### 5 35 

### g at the maximum proposed application rate for pyrasulfotole. Therefore, EFED's screening level analysis shows that the possibility ofindirect effects from the proposed use ofpyrasulfotole on cereal grains to listed species (generalists and obligates) that may depend on dicots and/or mammals and obligates that rely on aquatic vascular plants for survival cannot be precluded. Therefore, at this time, no Federally-listed taxa can be excluded from the potential for direct and/orindirect effects from the proposed uses of pyrasulfotole (see Table 22). Species-specific concerns for indirect effects to listed organisms will require a determination ofthe coincidence of pyrasulfotole use with locations of listed species and the biologically based resources upon which they depend. Lower Bound Slope Uooer Bound 2.23 1.66 1in 538 1 in 64.9 2.8 4.52 2 -

p~ 1in 7,420 1 in 294,000 1 in 44TABLE 22. Listed Species Risks Associated with Potential Direct or Indirect

Terrestrial and semi-aquatic plants - dicots LISTED TAXON

Terrestrial and semi-aquatic ~lants - monocots

Yes DIRECT EFFECTS

No

Terrestrial phase amphibians INDIRECT EFFECTS

yes1

- - Insects

Birds Effects Due to the Proposed Applications of Pyrasulfotole on Cereal Grains. I

-

1

-

-

-

-

-

-

-

-

-

-

-

-

-

- No

No

Reptiles

Mammals

Aquatic plants yes1

yes'

No

Yes (chronic)

Yes

Freshwater fish

Aquatic phase amphibians

Freshwater crustaceans yes'

yes'

yes'

Mollusks

(4). Critical Habitat No

No

No

Marinelestuarine fish

Marinelestuarine crustaceans

In the evaluation ofpesticide effects on designated critical habitat, consideration is given to the physical and biological features (constituent elements) of a critical habitat identified by the U. S.Fish and Wildlife and National Marine Fisheries Services (the yes'

yes'

yes'

No yes1



### he nonlisted LOC was exceeded for terrestrial and semi-aquatic plants (dicots), the listed LOC was exceeded for aquatic vascular plants, and the chronic risk LOC was exceeded for some small mammals (95 g)

. Therefore, the potential for adverse effects to those species that rely either on a specific plant or animal species (specifically aquatic vascular plants, terrestriallsemi-aquatic dicots, or mammals) or multiple plant or animal species (specifically terrestriaysemi-aquatic dicots and mammals) cannot be precluded. Indirect effects may include general habitat modification, host plant loss, and food supply disruption. No

No yes'

yes'Services) as essential to the conservation of a listed species and which may require special management considerations or protection. The evaluation of impacts for a screening level pesticide risk assessment focuses on thebiological features that are constituent elements and is accomplished using the screening-level taxonomic analysis (RQs) and levels of concern (LOCs) that are used to evaluate direct and indirect effects to listed organisms.

The screening-level risk assessment has identified potential concerns for indirect effects on listed species for those organisms dependant upon plants and somemammals. In light ofthe potential for indirect effects, the next step for EPA and the Services is to identify which listed species and their designated critical habitat(s), if applicable, are potentially implicated. Analytically, the identification of such species and their critical habitat can
occurby determining whether the action area overlaps designated critical habitat or the occupied range of any listed species. If so, EPA would examine whether the pesticide's potential impacts on non-listed species would affect the listed species indirectly, or directly affect a constituent element ofthe critical habitats. At present, the information reviewed by EPA does not permit use ofthis analytical approach to make a definitive identification of species that are potentially impacted indirectly or designated critical habitats that arepotentially impacted directly by the proposed uses ofpyrasulfotole.

This screening-level risk assessment for critical habitats provides a listing of potential biological features that, if they are constituent elements of one or more critical habitats, would be of potential concern. These correspond to the taxa identified above (i.e., dicots, aquatic vascular plants, and mammals) asbeing of potential concern for adverse effects. This should serve as an initial step in problem formulation for further assessment of designated critical habitat impacts outlined above, should additional work be necessary.
(5). Co-occurrence Analysis

The goal ofthe analysis for co-location is to determine whether sites ofpesticide use are geographically associated with known locations of listed species [following the convention ofthe Services, the word 'species' in this assessment may actually apply to a 'species', 'subspecies', or an Evolutionary Significant Unit (ESU)]. At the screening level, this analysis is accomplished using the LOCATES (version 2.10.3) database. The database uses location information for listed species at the county level and compares it to agricultural census data (fiom 2002) for crop production at the same county level of resolution. The product is a listing of Federally-listed species that are located within counties known to produce the crops upon which the pesticide will be used, in this case cereal grains (i.e.,wheat, barley, oats, and triticale). For direct effects, only listed dicots, aquatic vascular plants, and mammals will be considered, since they were the onlytaxa to have RQs above the listed species LOC. For indirect effects, all other taxa will be considered since there is a potential for indirect effects to taxa that might rely on plants and/or mammals for some stage oftheir life-cycle.

LOCATES identified a total of 817listed species that overlapped at the county-level with areas where wheat, barley, oats, and/or triticale are grown. Among these species, 3 18 aredicots, 

### 13 are aquaticmonocots, and 

### 59 are mammals (see 

### APPENDIX H for a complete species list). Therefore, at the county-level, there is the potential for a total of 

### 390 listed species to be directly affected by pyrasulfotole use, while 427 species may be indirectly affected by the use ofthe chemical. The number of county co-occurrences by taxa per state can be found in Table 23.

This preliminary analysis indicates that there is a potential for pyrasulfotole use to overlap with listed species and that a more refined assessment is warranted. The more refined assessment should involve clear delineation ofthe action area associated with proposed uses ofpyrasulfotole and best available information on the temporal and spatial co-location of listed species with respect to the action area. This analysis has not been conducted for this assessment.C. Description 

### of Assumptions, Limitations, Uncertainties, Strengths andData Gaps

A source of uncertainty is the nature ofthe unextractable residues formed during pyrasulfotole degradation in soils. In aerobic soil metabolism studies unextractable residues were identified at maximums of 35-62% of applied radioactivity in three soils. Theunextractable residues are uncharacterized and it is uncertain whether they consist of degradates of risk concern. Under sterile conditions these unextractable residues were not formed suggesting that the formation of them is microbially mediated. Aerobic soil metabolism half-lives were estimated based onparent concentrations alone (excluding unextractable residues). To the extent that these unextractable residues are of risk
concern, the estimated half-lives will be underestimated compared to a total toxic residue approach for estimating half-lives. However, given the persistence ofpyrasulfotole parent only, a total toxic residue approach for calculating aerobic soil metabolism halflife would not impact PRZMIEXAMS modeled EECs appreciably. In fact, assuming pyrasulftole is completely stable to aerobic soil metabolism results in peak EECs for the TX wheat scenario that are identical (to two significant figures) to those used in this
assessment.

The ecological pond modeled with EXAMS is a static water body of fixed volume with

no outlet. Sincepyrasulfotole ispersistent in aquatic environments and since the ecological pond has no outlet, there was a modeled accumulation ofpyrasulfotle in the pond throughout the 30 year simulations. Exposure endpoints, in this assessment, are based on yearly peak concentrations. In the case of persistent compounds, a 1 -in-10year EEC does not reflect varying meteorological conditions that are expected once every 10 years, since the yearly peaks are not independent but are actually correlated to the previous year's peak concentration. Estimated peak concentrations in the ecological pond are only high enough to result in an exceedance ofthe listed species LOC for vascular plants after 26 years of annual applications ofpyrasulfotole assuming no dissipation whatsoever in the pond (APPENDIX C). Pyrasulfotle concentrations in flowing water bodies are not expected to accumulate from year to year because of downstream dilution. Risk to aquatic plants resulting from accumulation ofpyrasulfotle from multiple years of application is not likely in flowing systems.

Even though pyrasulfotole is very soluble and moderately mobile to mobile based on the results ofbatch equilibrium studies, in aquatic systems it does variably partition to the sediment and forms unextractable residues and persists as parent. Additionally, there is

some evidence that pyrasulfotle may become less mobile as it it is exposed to viable microbs under certain conditions. Since PRZMIEXAMS modeling requires one input for soil-water partitioning coefficient that is constant throughout the simulation, the modeled partitioning to the sediment may be underestimated relative to the aerobic aquatic metabolism studies. Therefore, there may be a potential for pyrasulfotole (andlor residues) to accumulate in the benthos at levels that could result in toxic exposure to benthic and epibenthic aquatic organisms, especially those that consume soil (e.g., Hexagonia spp.). The potential risk to benthic and epibenthic organisms could not be assessed here, however, because a lack of available toxicity data for these taxa.Therefore, risks to benthic and epibenthic organisms from the use of pyrasulfotole on cereal grains cannot be precluded at this time.

Related to these issues, estuarinelrnarine invertebrates (i.e., mysids) are considerably

more sensitive to pyrasulfotole on an acute exposure basis than the other aquatic animals tested. The reason(s) for this difference in toxicity is not clear. Because no toxicity data for chronic exposures are available for estuarinelrnarine invertebrates and toxicity data from a freshwater invertebrate do not appear to be a good surrogate for measures of toxicity in this taxon, there is the potential for adverse effects to estuarinelrnarine invertebrates from chronic exposure to pyrasulfotole (especially since it could accumulate in the benthos). However, given that: (1) the potential use sites for the proposed uses largely fall outside of estuarinelrnarine environments, with the possible exceptions of CA and the mid-Atlantic states; (2) the aquatic EECs used in this assessment are based on a staticwater-body with no outlet, and, thus, would likely be higher than those in estuarinelrnarine environments; and (3) estuarinelrnarine invertebrates would need to be 1,293 times more sensitive to pyrasulfotole than freshwater invertebrates on a chronicexposure basis to exceed the Agency's chronic risk LOC, risks to estuarinelrnarine invertebrates from chronic exposure to pyrasulfotole are not expected. However, the lack of data onthe chronic toxicity of pyrasulfotole to estuarinelrnarine invertebrates does add uncertainty to this risk assessment.

V. REFERENCES

Cohen, S.Z., Creeger, S.M.,Carsel, R.F., Enfield, C.G. (1984). In "Treatment and Disposal of Pesticide Wastes;" Krueger, R.F., Seiber, J.N., Eds.; ACS Symposium Series No. 259, American Chemical Society: Washington, DC; pp. 297-325.

Fletcher, J.S., J.E. Nellessen, and T.G. Pfleeger. (1994). Literature review and evaluation of the EPA food-chain (Kenaga) nomogram, an instrument for estimating pesticide residues on plants. Environ. Tox. Clzem. 13:1383-1391.

Hoerger, F., and E.E. Kenaga. (1 972). Pesticide residues on plants: Correlation of representative data as a basis for estimation oftheir magnitude in the environment. In F. Coulston and F. Korte, eds., Environmental Quality and Safety: Chemistry, Toxicology, and Technology, George Thieme Publ, Stuttgart, West Germany, pp. 9-28.

Urban, D.J., and N.J. Cook. (1986). Hazard Evaluation Division Standard Evaluation Procedure Ecological RiskAssessment. EPA 54019-85-001. U.S. Environmental Protection Agency, Office of Pesticide Programs, Washington, DC.

USEPA. (2006). Water Models. U.S. Environmental Protection Agency, Pesticides: Science and Policy. Last updated May 2, 2006. Online at: http://www.epa.gov/oppefedl/models/water/,

USEPA. (2004). Overview ofthe Ecological RiskAssessment Process in the OfJice ofpesticide Programs, U.S. Environmental Protection Agency. Office of Prevention, Pesticides and Toxic Substances, Office of Pesticide Programs, Washington, DC. January 23,2004.

USEPA. 2002. Guidance for Selecting Input Parameters in Modeling the Environmental Fate and Transport of Pesticides. U.S. Environmental Protection Agency, Office of Prevention, Pesticidesand Toxic Substances, Office of Pesticide Programs, Environmental Fate and Effects Division. Feb. 28,2002. Online at: http://www.epa.gov/oppefedl/models/water/input_guidance228-02.html.

USEPA. (1998). Guidelines.for EcologicalRisk Assessment, Final. EPAl63 OR-95/002F. Risk Assessment Forum, U.S. Environmental Protection Agency, Washington, DC.

Submitted Studies:

MRZD: 439048-25 Machado M.W. 1995. RPA203328 

### - Acute toxicity to rainbow trout (Oncorhynchus mykiss) under flow-through conditions. Springborn Laboratories, Inc., Wareham, Massachusetts, USA; Environmental Sciences Division. Bayer CropScience AG, Report No.: R005254, Report includes Trial Nos.: 10566.01 94.6328.108. Edition Number: -1 70722-01-1.

MRID: 4471 88-01 Sousa J.V. 1 998. RPA 203328 - Acute toxicity to mysids (Mysidopsis bahia) under static acute conditions. Springborn Laboratories, Inc., Massachusetts, USA. Bayer CropScience AG, Report No.: C026471, Report includes Trial Nos.: 10566.0797.6436.5 10. Edition Number: -21 1469- 01-1.

MRID: 435732-41 Putt A.E. 1994. RPA203328 - Acute toxicity to daphnids (Daphnia magna) under flow-through conditions. Springborn Laboratories, Inc., Wareham, Massachusetts, USA;Environmental Sciences Division. Bayer CropScience AG, Report No.: R005204, Report includes Trial Nos.: 10566.0194.6329.1 15. Edition Number: -1 70649-01 -1.

MRID: 446935-01 Gallagher S.; Grimes J.; Beavers J.; Kendall T. 1998. RPA 203328: A Dietary LC50 Study with the Northern Bobwhite. Wildlife International Ltd., Easton, MD, USA. Bayer CropScience AG, Report No.: B004404, Edition Number: -241327-01-1.

MRID: 46801 7-42 Odin-Feurtet M. 1997. RPA 203328 - Acute toxicity (14-day) to earthworms (Eiseniafoetida) - Artificial soil method. Rhone-Poulenc Agro, Sophia Antipolis, FRA. Bayer CropScience AG, Report No.: C026475, Edition Number: -21 1477-01 -2.

MRID: 439048-26 Hoberg J.R. 1995. 5-day toxicity to the freshwater green alga, Selenastrum capricornutum. RPA203328. Springborn Laboratories, Inc.,Wareham, Massachusetts, USA; Environmental Sciences Division. Bayer CropScience AG, Report No.: R005374, Report includes Trial Nos.: 10566.0595.6367.430. Edition Number: -1 70835-01-1.

MRID: 443999-10 Hoberg J.R. 1997. RPA203328 technical - Toxicity to the duckweed, Lemna gibba. Springborn Laboratories, Inc., Wareham, Massachusetts, USA. Bayer CropScience AG, Report No.: R004953, Report includes Trial Nos.: 10566.0797.6441.410. Edition Number: -166893-01-1.MRID: 443999-06 Teixeira D.; Teixera D. 1997. Amendment to the final study report - RPA203328 

### - Determination of effects on vegetative vigor of ten plant species. Springborn Laboratories Inc., Wareham, MA, USA. Bayer CropScience AG, Report No.: R005076, Report includes Trial Nos.: 10566.0797.6442.61 0. Edition Number: -1 70405-02-1.

MRID: 443999-07 Teixeira D. 1997. RPA203328 

### - Determination of effects on seedling emergence of ten plant species. Springborn Laboratories Inc., Wareham, MA, USA. Bayer CropScience AG, Report No.: R005075, Report includes Trial Nos.: 10566.0797.6440.610. Edition Number: -1 70402- 01-1.

MRID: 468017-21 Christ, M.T. 2005. The 48-Hour Acute Toxicity to the Water Flea, Daphnia magna, in a Static SystemAE 03 17309 Technical 97.4% w/w. Unpublished study performed by Bayer CropScience Ecotoxicology Department, Research Triangle Park, NC. Study report number 02DT35542-a. Study sponsored by Bayer CropScience, Ecotoxicology Department, Research Triangle Park, NC.

MRID: 468017-43 Moser, Th. and Scheffczyk, A. 2004. Isoxaflutole-RPA 203328 (AE B197555): Reproduction toxicity to the earthworm Eisenia fetida in artificial soil. Bayer CropScience AG, Report No.: C041342, StudyNo.: P15RR.

MRID: 468017-22 Dionne, Emily. 2005. AE 0317309-Acute Toxicity to Eastern Oysters (Crassostrea virginica) Under Flow-Through Conditions. Springborn Smithers Laboratories, Wareham, MA. Bayer CropScience, Stilwell, KS.

MRID: 46801 7-23 Hoberg, James R. 2004. AE 031 7309- Acute Toxicity to Mysids (Americamysisbahia) Under Static Conditions. Springborn Smithers Laboratories, Wareham, MA. Bayer CropScience, Stilwell, KS.

MRID: 4680 17-24 Chnst, M.T. 2005. The 96 Hour Acute Toxicity to theRainbow Trout, Oncorhynchus mykiss, in

a Static System; AE 0317309 Technical 97.4% w/w (Amended Report). Unpublished study performed by Bayer CropScience, Research Park Triangle, NC. Laboratory report number 02DT35541-a. Study sponsored by Bayer CropScience, RTP, NC.

MRID: 468017-25 Christ, M.T. 2005. The 96 Hour Acute Toxicity to the Bluegill Sunfish,Lepomismacrochirus, in a Static System, AE 0317309Technical, 98.2% w/w (Amended Report). Unpublished study performed by Bayer CropScience, Ecotoxicology Department, Research Triangle Park, NC. Laboratory report number 02DT35540-a. Study sponsored by Bayer CropScience, Ecotoxicology Department, Research Triangle Park, NC.

MRID: 468017-26 Banman, C.S., M.E. Kern and C.V. Lam. 2004. Acute Toxicity ofAE 0317309 Technical to the Sheepshead Minnow (Cyprinodon variegates) Under Static Conditions. Unpublished study performed by Bayer CropScience, Research and Development, Stilwell, KS. Laboratory study number EBAIX012. Study sponsored by Bayer CropScience, Research Triangle Park, NC.MRID: 468017-27 Kern, M.E., and C.V. Lam. 2004. Chronic Toxicity of AE 0317309 Technical to the Daphnia magna Under Static Renewal Conditions. Unpublished study performed by Bayer CropScience, Stilwell, KS. Laboratory Study No. EBAIX014. Study submitted by Bayer CropScience, Research Triangle Park, NC.

MRID: 46801 7-28 Kern, M.E., and C.V.Lam. 2004. Early Life Stage Toxicity ofAE 0317309 Technical to the Fathead Minnow (Primephalespromelas)Under Flow-Through Conditions. Unpublished study performed by Bayer CropScience, Stilwell, KS. Laboratory Study No. EBAIXO 15 (A984 1201). Study submitted by Bayer CropScience, Research Triangle Park, NC.

MRID: 46801 7-29 Stoughton, T.L. 2006. Technical AE0317309: An Acute Oral with Northern Bobwhite. Unpublished study performed by Bayer Corporation, Agriculture Division, Research and Development Department, Environmental Research and Toxicology, Stilwell, Kansas. Study No. A971 17011201125. Study sponsored by Bayer CropScience, Research Triangle Park, NC.

MRID: 468017-30 Stoughton, T.L. 2005. Technical AE0317309: A Subacute Dietary LC50 with Northern Bobwhite. Unpublished study performed by Bayer Corporation, Agriculture Division, Research and Development Department, Environmental Research and Toxicology, Stilwell, Kansas. StudyNo. A972 170llEBAIM002. Study sponsored by Bayer CropScience, Research Triangle Park, NC.

MRID: 46801 7-31 Stoughton, T.L. 2005. Technical AE0317309: A Subacute Dietary LCsowith Mallards. Unpublished study performed by Bayer Corporation, Agriculture Division, Research and Development Department, Environmental Research and Toxicology, Stilwell, Kansas. Study No. A9720801lEBAIM003. Study sponsored by Bayer CropScience, Research Triangle Park, NC.

MRID: 468017-32 Sabbert, T.J. 2004. Effect of Technical AE 0317309 on Northern Bobwhite Reproduction. Unpublished study performed by Bayer CropScience, Stilwell, KS. Laboratory Study No. EBAIX016. Study submitted by Bayer CropScience, Research TrianglePark, NC.

MRID: 46801 7-33 Sabbert, T.J. 2005. Effect ofTechnical AE 0317309 on Mallard Reproduction. Unpublished study performed by Bayer CropScience, Stilwell, KS. Laboratory StudyNo. EBAIXO17. Study submitted by Bayer CropScience, Research TrianglePark, NC.

MRID: 468017-34 Waltersdorfer, A. 2002. Oral toxicity (LD50) to honey bees (Apis mellifera L.), Substance technical. Bayer CropScience GmbH, Ecotoxicology, Frankfurt, Germany. Bayer CropScience GmbH, Ecotoxicology, Frankfurt, Germany.

MRID: 468017-35 Waltersdorfer, A. 2002. Contact toxicity (LD50)to honey bees (Apis mellifera L.), Substance technical. Bayer CropScience GmbH, Ecotoxicology, Frankfurt, Germany. Bayer CropScience GmbH, Ecotoxicology, Frankfurt, Germany.MRID: 46801 7-36 Kern, M.E., Banman, C.S. and C.V. Lam. 2004. Toxicity ofAE 0317309 Technical to Duckweed (Lemnagibba G3) Under Static Conditions. Unpublished study performed by Bayer CropScience, Research and Development Department, Stilwell, KS. Laboratory report number EBAIX009 (A9883701). Study sponsored by Bayer CropScience, Research Triangle Park, NC.

MRID: 46801 7-37 Kern, M.E. and C.V. Lam. 2004. Toxicity of AE 0317309 Technical to the Green Alga Pseudokirchneriella subcapitata (a.k.a. Selenastrum capricornutum). Unpublished study performed by Bayer CropScience, Research and Development Department, Stilwell, KS. Laboratory report number EBAIXOOS (A9883501). Study sponsored by Bayer CropScience, Research Triangle Park, NC.

MRD: 468017-38 Kern, M.E. and C.V. Lam. 2004. Toxicity of AE 0317309 Technical to theFreshwater Diatom Naviculapelliculosa. Unpublished study performed by Bayer CropScience, Research and Development Department, Stilwell, KS. Laboratory report number EBAIX006 (A9883401). Study sponsored by Bayer CropScience, Research Triangle Park, NC.

MRID: 46801 7-39 Kern, M.E.,C.S. Banman and C.V. Lam. 2004. Toxicity ofAE 0317309 Technical to the BlueGreen Algae Anabaena,flos-aquaea. Unpublished study performed by Bayer CropScience, Research and Development Department, Stilwell, KS. Laboratory report number EBAAIX008 (A9883801). Study sponsored by Bayer CropScience, Research TrianglePark, NC.

MRID: 4680 17-40 Kern, M.E., C.S. Banman and C.V. Lam. 2004. Toxicity of AE 0317309Technical to the Saltwater Diatom Skeletonema costatum. Unpublished study performed by Bayer CropScience, Research and Development Department, Stilwell, KS. Laboratory report number EBAAIX007 (A9883601). Study sponsored by Bayer CropScience, Research TrianglePark, NC.

MRID: 468017-41 Lechelt-Kunze, C. 2004. AE 03 17309,substance, technical (Code: AE 0317309 00 1 C96 0001): Acute Toxicity to Earthworms (Eisenia.fetida) tested in Artificial Soil. Unpublished study performed by Bayer CropScience AG, Institute for Ecotoxicology, Monheim, Germany. Study No. E 3 10 267 1-0. Study sponsored by Bayer CropScience AG, Monheim, Germany.

MKID: 46801836 Schungel, M. (2004) AE 0317309: Acute Toxicity in the Rat After Oral Administration. Project Number: AT01 067, Tl3073706, TXAIM001. Unpublished study prepared by Bayer Ag Inst. of Toxicology. 25 p.

MRID: 46801907 Eiben, R. (2005) Two-Generation Reproduction Study in the Wistar Rat by Administration in the Diet. Project Number: T2063193, TXAIXOO5, AT02705. Unpublished study prepared by Bayer Ag Inst. of Toxicology. 1328 p.

MRID: 46801917 Gilmore, R.; Sheets, L.; Hoss, H. (2006) A Developmental Neurotoxicity Screening Study with Technical Grade AE 0317309 in Wistar Rats. Project Number: 04/D72NE1201439. Unpublished study prepared by Bayer Corp. 1083 p.MRID: 468019-26 Pallet, K and H. Gosch. 2006. Non-target terrestrial plants: Seedling emergence and growth test (Tier 2) Suspo-emulsion: 50+12.5 g/L (Code: AE 031 7309 02 SE06A102). Unpublished study performed by Bayer CropScience GmbH, Frankfurt am Main, Germany. Laboratory study number SE041006. Study sponsored by Bayer CropScience GmbH, Frankfurt am Main, Germany.

MRID: 468019-27 Pallet, K. and H. Gosch. 2006. Non-target terrestrial plants: Vegetative vigor test (Tier 2) AE 0317309

### + Mefenpyr di-ethyl (AE F107892); Suspo-emulsion: 50+12.5 g/L (Code: AE 0317309 02 SE06 A102). Unpublished study performed by Bayer CropScience GmbH, Ecotoxicology, Frankfurt am Main, Germany. Laboratory report number VV04/005. Study sponsored by Bayer CropScience GmbH, Ecotoxicology, Frankhrt am Main, Germany.

MRID: 4680 19-36 Pallet, K. and H. Gosch. 2006. Non-target terrestrial plants: Seedling emergence and seedling growth test (Tier 2); AE 0.317309+Mefenpyr di-ethyl+Bromoxynil (Code: AE 0317309 03 EC23 A8). Unpublished study performed by Bayer CropScience GmbH Ecotoxicology, Frankfurt am Main, Germany. Laboratory report number SE 05/00 1. Study sponsored by Bayer CropScience GmbH Ecotoxicology, Frankfurt am Main, Germany.

MRID: 468019-37 Pallet, K. and H. Gosch. 2006. Non-target terrestrial plants: Vegetative Vigor test (Tier 2), AE 0317309+Mefenpyr di-ethyl+Bromoxynil (Code: AE 03 17309 03 EC23 A8). Unpublished study performed by Bayer CropScience GmbH, Frankfurt am Main, Germany. Laboratory report number VV 05/002. Study sponsored by Bayer CropScience GmbH, Frankfurt am Main, Germany.

MRID: 4680 19-37 Dobbs, M.G.,M. Lenz, B. Meyer, and J-Z. Tang. 2006. Ecological risk assessment for the cereal herbicide AE 0317309. Unpublished study performed by Bayer CropScience,
,Research Triangle Park, NC. Laboratory Study No. EBAIP004. Study submitted by Bayer CropScience, Research Triangle Park, NC.

MRID: 4680 1703 Maurer, T.; Eyrich, U.; Fliege, R. (2003) Adsorption/Desorption ofAE 0317309on Five Soils and One Sediment. Project Number: CPI02l014, M0/03/012996, MEF/186/03. Unpublished studyprepared by Bayer Cropscience Gmbh. 84 p.

MRID: 46801 705 Ripperger, R. (2004) [Pyrazole-3-(Carbon 14)] AE03 17309: Hydrolytic Degradation. Project Number: 200578, A9072401. Unpublished study prepared by Bayer Corp. 59 p.

MRID: 4680 1706 Ripperger, R.; Meyer, B. (2005) [(Carbon 14)-UL-Phenyl] and [(Carbon 14)-3-Pyrazole] AE 0317309: Phototransformation in Water. Project Number: 200987, A9082401. Unpublished study prepared by Bayer Corp. 64p.MRID: 46801717 Lenz, M. (2006) Terrestrial Field Dissipation ofAE 0317309in North Dakota Soil, 2004. Project Number: MEAIY007, AI/002/S05/02. Unpublished study prepared by Bayer Corp. and Agvise Inc. 188p.

MRID: 46801718 Lenz, M. (2006) TerrestrialField Dissipation of AE 0317309 in Washington Soil, 2004. Project Number: MEAIY009, AI/002/S05/02. Unpublished study prepared by Bayer Corp., Agvise Inc. and Qualls Agricultural Laboratories, I. 195 p.

MRID: 46801719 Belyk, M. (2006) Terrestrial Field Dissipation of AE 0317309in Canada, 2003-2004. Project Number: 03BCS01, MEAIM004, AI/002/S05/01. Unpublished study prepared by Bayer Corp., Vaughn Agricultural Research Serv., Ltd. and Ag-Quest Inc. 333 p.APPENDIX A: ECOTOX 

### Results

All ofthe references identified by ECOTOX were excluded because they were not written in English.
Dollinger, Markus, Santel, Hans-Joachim, Gesing, Ernst Rudolf, and Hacker, Erwin(20050922). Synergistic herbicidal compositions comprising thien-3-yl

### sulphonylamino(thio)carbonyl-triazolin(thi)one derivatives and 4-HPPD inhibitors. (Bayer CropscienceAg, Germany) PCTInt. Appl. 31 pp. Chem Codes: Chemical of Concern: PST Reiection Code: NON-ENGLISH.
Huff, Hans Philipp, Hacker, Erwin, Bojack, Guido 

### ,Fischer, Reiner, Feucht, Dieter, and Lehr, Stefan (20060302). Herbicidal compositions comprising ketoenols. (Bayer Cropscience G. m.

### b. H., Germany) Ger. Ofen. 31 pp. Chem Codes: Chemical of Concern: PST Reiection Code: NON-ENGLISH.

Schmitt, Monika, Van Almsick, Andreas, Preuss, Rainer, Willms, Lothar, Auler, Thomas, Bieringer, Herrnann, and Thuenvaechter, Felix (2001 1011). Benzoylpyrazoles and their use as herbicides. (Aventis CropScience GmbH, Germany) PCTInt. Appl. 32 pp. Chem Codes: Chemical of Concern: PST Reiection Code: NON-ENGLISH.
Schmitt, Monika, Willms, Lothar, Ziemer, Frank, Rosinger, Christopher, Bieringer, Herrnann, Huff, Hans Philipp, and Hacker, Erwin (20030530). Herbicidal compositions containing benzoylpyrazoles and safeners. (Bayer CropScience GmbH, Germany)PCT Int. Appl. 30 pp. Chem Codes: Chemical of Concern: PST Rejection Code: NON-ENGLISH.

### APPENDIX 

### B: Environmental Fate and Transport Study Details

Abiotic Degradation
Hydrolysis

In an 

### acceptable study (MRID 46801705), the hydrolysis ofpyrasulfotole at 0.14 mg a.i./L, was studied in the dark at 24.9 k0.02"C in sterile aqueous buffered pH 5,pH 7, and pH 9 solutions for 30 days. [14~]-~yrasulfotole avraged 98.4-100.4% ofthe applied in the pH 5 solutions and 98.6-100.3% in the pH 7 solutions throughout the experiment. In the pH 9 solution, [14~]-pyrasulfotole averaged 96.6-98.1% ofthe applied through 22 days posttreatment and 95.7% at 30 days. Half-lives were not calculated because pyrasulfotole was stable to hydrolysis.

Aqueous Photolysis

In an 

### acceptable study (MRID 46801706), the aqueous phototransformation of pyrasulfotole at ca. 1mg a.i./L, was studied in sterile pH 7 buffer (0.01M phosphate) at 25 k 1"C under continuous irradiation using a UV-filtered xenon arc lamp for 2 12hours. ['4~]-~yrasulfotole (both labels) did not degrade in either the irradiated or dark control solutions. In the irradiated solutions, [14~]-pyrasulfotole ranged from an average of 97.7% to 100.7% ofthe applied with no pattern of decline during the 9-day experiment. In the dark controls, [14~]-pyrasulfotole ranged from an average 99.6% to 102.0%ofthe applied with no pattern of decline. A half-life was not calculated because pyrasulfotole was stable in both the irradiated and dark control solutions.

Soil Photolysis

In an 

### acceptable study (MRID 46801707), the phototransformation of pyrasulfotole, at 0.51 mglkg (equivalent to 75 g a.i./ha), was studied on silt loam soil [pH 7.4, organic matter 7.1%] from North Dakota that was irradiated continuously using a UV-filtered xenon lamp for 9 days at 25

# * 0.1"C. The intensity of the lamp was 680 w/m2,and 7.0 hours of irradiation with the artificial light was reported to be equivalent to I solar day in lateJune in Phoenix, Arizona. ['4~]-~yrasulfotole dcreased from an average of 104.2% ofthe applied at time 0 to 87.2% in the irradiated samples and 89.9% in the dark controls at study termination (9 days posttreatment). Concentrations were variable and were affected by overall recoveries of 14c-residues;[14~]-pyrasulfotole comprised 97.9% ofthe recovered at time 0 and 90.0% and 93.6% in the irradiated and dark controls, respectively, at 9 days posttreatment. No major transformation products were isolated from either the irradiated or dark control soils. No minor transformation products, which averaged 11 .O% of the applied, were identified in either the irradiated or dark control soils. Based on first order linear regression analysis, pyrasulfotole dissipated with half-lives of 32.5 days in the irradiated samples (continuous irradiation) and 64.2 days in the dark controls. Thehalf-lives are ofuncertain value because they are extrapolated well beyond the duration ofthe study, between replicate variability at some intervals is ca. 5% ofthe applied, and the calculations are based on the assumption thatdegradation follows a linear pattern. The phototransformation half-life for pyrasulfotole, was 66 days based on the continuous irradiation used in the study. The study author stated that 7.0hours of continuous irradiation with the artificial light was equivalent to 1day of natural sunlight in Phoenix, Arizona (33.26"N latitude). Therefore, the environmental phototransformation half-life is expected to be 

### ca. 227 days in Phoenix, AZ.

Metabolism

Aerobic Soil Metabolism

In an acceptableaerobic soil metabolism study (MRID 46801709), [I4c]- pyrasulfotole dissipated in a Goldsboro loamy sand soil (pH 5.6-6.2, organic carbon 1.2%) from North Carolina following a biphasic pattern decreasing quickly from 96.4- 97.5% ofthe applied at day 0 posttreatment to 53.8-54.8% at 4 days and was 40.0-40.7% at 7 days, then dissipation significantly slowed with [~4~]-pyrasulfotole comprising 20.2- 22.8% at studytermination. The log-linear half-life was 240 days (r2= 0.4428) and the nonlinear half-life was 69 days (r2= 0.441). Based on a 2-compartment, 4-parameter exponential model (DFOP) the DTS0 and DTgO estimates were 5.8 and 749 days, respectively 

## (2

= 0.977). The observed DTS0 and DT90values were 4-7 days and >358 days, respectively. Soil samples were extracted using an Accelerated Solvent Extraction (ASE) system, which conducted two-phase ["mild" (40°C, 100bar) and "aggravated" (1OO0C, 100bar) conditions], automated, multi-step extractions with acetonitri1e:water (2: 1,v:v) as the extraction solvent. 2-Methylsulfonyl-4-trifluoromethylbenzoic acid (AE B 197555) was a major transformation product in phenyl-label treated soil detected at a maximum 12.2% ofthe applied at 7 days posttreatment and was 4.2% at studytermination. No minor transformation products were identified for either label. Unextractable I4c-residues increased from 1.7-1.9% at day 0 to maximums of49.7-50.1% at 100-120 days and were 43.2-44.8% at 358 days. At study termination, volatilized I4c02 totaled 17.3%-18.6%of the applied. Under sterile (autoclaved soil, both labels) conditions, parent pyrasulfotole comprised 94.8-95.4% of the applied at 120 days (final interval), with AE B197555 in phenyl-label treated soil detected at 13.2%at any interval. At studytermination, extractable and unextractable 14~-residues were 95.6-99.3% and 2.7-3.5% of the applied, respectively, with volatilized 

## I4co2 and volatile I4c-organiccompounds S0.2%.

In an acceptableaerobic soil metabolism study (MRID 46801710), [I4c]- pyrasulfotole dissipated in a LaDelle silt loam soil (pH 7.0-7.3, organic carbon 4.7%) fromNorth Dakota following a biphasic pattern with a steady decline during the initial 2 months posttreatment, decreasing from 94.3-97.1% ofthe applied at day 0 to 47.2-50.0% at 65 days, then dissipation slowed with ['4~]-pyrasulfotole comprising 22.0-24.9% at study termination. The log-linear half-life for both radiolabels was 161 days (r2= 0.8227) and the nonlinear half-life was 95 days (r2= 0.9144). The DTS0 and DT90 estimates based on a 2-compartment, 4-paramter exponential model (DFOP) were 63 and 1424 days, respectively (r2= 0.998). The observedDTS0 and DTg0and values were 50-65 days and >358 days, respectively. Soil samples were extracted using an Accelerated Solvent Extraction (ASE) system, which conducted two-phase ["mild" (40°C, 100bar) and "aggravated" (IOO°C, 100bar) conditions], automated, multi-step extractions with acetonitri1e:water (2:1,v:v) as the extraction solvent. 2-Methylsulfonyl-4-trifluoromethylbenzoicacid (AE B197555) was a minor transformation product in phenyl-label treated soil detected at a maximum 3.8% of the

a plied; no other minor or major products were identified for either label. Unextractable 

# IP

C-residues increased from 0.4-1.1% at day 0 to maximums of 31.3-35.2% at 155-190 days and were 30.1-30.7% at 358 days. At studytermination, volatilized 

## I4co2 totaled 33.5-40.5% ofthe applied. Under sterile (autoclaved soil, both labels) conditions, parent pyrasulfotole comprised 93.6-94.2% ofthe applied at 120 days (final interval), with AE B197555 in phenyl-label treated soil detected at a maximum 3.7% at study termination. At 120days, extractable and unextractable 14c-residueswere 93.6-97.9% and 3.8-5.2% ofthe applied, respectively, with volatilized I4c02 and volatile '4~-organic ompounds 50.4%.

In a supplemental aerobic soil metabolism study (MRID 4681701I),phenyllabeled pyrasulfotole dissipated in a sandy loam soil 

### (pH 5.9-6.6, organic carbon 1.4%) from Germany from a mean 100.0%ofthe applied at day 0 to 48.0% at 29 days and was 19.0% at 120days. Pyrazole-labeled pyrasulfotole reached the observed DT50somewhat faster decreasing from 98.4% at day 0 to 48.9% at 21 days and was 17.3%at study termination. The log-linear half-life for both radiolabels was 48 days (r2= 0.9127) and the nonlinear half-lifewas 32.4 days (r2= 0.9503). The 

### DTS0 and 

### DT90estimates based

on a 2-compartment, 4-parameter exponential model (DFOP) were 23 and 208 days, respectively (r2= 0.990). The observed 

### DTS0 and 

### DT90values were between 14 and 29 and >I20 days, respectively. Soil samples were extracted using an Accelerated Solvent Extraction (ASE) system, which conducted two-phase ["mild" (40°C, 103 bar) and "aggravated" (lOO°C, 103bar) conditions], automated, multi-step extractions with acetonitri1e:water (2: 1,v:v) as the extraction solvent. 2-Methylsulfonyl-4-trifluoromethylbenzoicacid (AE B197555) was a minor transformation product in phenyl-label treated soil detected at a maximum 8.9 

### f0.4% of the applied; no other minor or major products were identified for either label. Unextractable I4c-residuesincreased from 2.1-2.7% at day 0 to 60.1-62.1% at study termination (120 days). At study termination, volatilized 

## I4co2 comprised total means of 16.3-18.0%ofthe applied, while volatile 14~-organic compounds were 50.1% at all intervals.

Table B.a. summarizes the various modeled used to describe the degradation kinetics in the aerobic soil metabolism studies.Anaerobic Soil Metabolism Table B.a. Summary ofModels Used to Fit Degradation Data in Aerobic Soil Metabolism Studies.

In an acceptable anaerobic soil metabolism study 

### (MRID 46801712), [l4c]- pyrasulftole-residues partitioned between the soil and water layer with mean (n = 2) distribution ratios (water:soil) of 1:22-28 immediately after flooding (30 days posttreatment), decreasing to 1:5 after 33 days (63 days posttreatment) and were 1 :7-11 at study termination (150 days posttreatment). The dissipation rate of ['4~]-pyrasulfotole significantly slowed with the conversion to anaerobic conditions. ['4~]-~yrasulfotole comprised means of 93.5-97.3% ofthe applied in the soil at day 0 posttreatment, then at day 0 post-flooding (30days posttreatment) was detected at 66.0-68.4% in the total system and was 62.2-64.1% at 120 days post-flooding (150 days posttreatment). In the water layer, [14~]-pyrasulfotole increased from means of 2.4-3.1% at day 0 post-flooding (30 days posttreatment) to 11.7-14.2% at 33 days (63 days posttreatment) and was 7.2- 7.7% at study termination. In the soil, ['4~]-pyrasulfotole decreased from means of 93.5- 97.3% at day 0 posttreatment to 62.9-66.0% at day 0 post-flooding (30days posttreatment) and was 53.3-56.5% at 90-120 days post-flooding (120-150 days posttreatment). Observed DTS0 values for yrasulfotole in the total system were >I20 

# ,B days. Calculated dissipation half-lives for [ C]-pyrasulfotole in the total system could not be determined due to insufficient dissipation post-flooding. Since the degradation rate could not be quantified, pyrasulfotole is assumed to be stable for the purposes ofrisk assessment.

Model Half-life (d)

Loamy sand, North Carolina (MRID 46801709) Model equation

Log-linear Nonlinear
DFOP Observed DT50190 r2

240
68.6

--

--
Silt loam, North Dakota (MRID 46801710) DTSO (d)

y = -0.0029~ + 3.7590

y = 58.6*exp(-0.0101*x)

y = 69.0*exp(-0.24*x) + 33.1*exp(-0.00 16*x)

--

Log-linear Nonlinear
DFOP Observed DT50190 DTBO (4

0.443
0.441
0.977

--

161 95.0

--

-- Sandy loam, Germany (MRID 46810711) --

-- 5.8

4-7

y = -0.0043~ + 4.2958

y= 87.2*exp(-0.0073*x)

y= 66.6*exp(-0.019*x)+31.2*exp(-0.0008*x)

--

Log-linear Nonlinear
DFOP Observed DT50/90 --

-- 747

>358

0.823 0.914 0.998

--

47.6
32.4

--

-- --

63

50-65

y = -0.01456 +4.3854

y = 9 1.4*exp(-0.0214*x)

y = 58.5*exp(-0.054*x)+37.7*exp(-0.0064*x)

-- --

1424

>358

0.913 0.950 0.990

-- --

23

14-29 --

208

>I20

### 2-Methylsulfonyl-4-trifluoromethylbenzoic acid (AE 

### B 197555) was the sole transformation product detected at maximum means of 5.1% (15 days post-flooding), 7.7% (day 0 post-flood) and 9.9% (15 and 61 days post-flood) ofthe applied in the water, soil and total system, respectively, of phenyl-label [14~]-pyrasulfotole treated soil and

was 4.1%, 5.1% and 9.2%, respectively, at studytermination. Phenyl-label unextractable 14c-residues increased from 0.8% at day 0 to 22.5% at studytermination. Pyrazole-label unextractable 14C-residues increased from 2.0% at day 0 to 24.9% at study termination. Maximum mean levels of volatilized I4c02 (identity not confirmed) detected were 2.6% and 6.6% ofthe applied for the phenyl- and pyrazolelabel treated soils,respectively, while volatile 14c-organic compounds were SO. 1 % (both labels) at all sampling intervals.
Aerobic Aquatic Metabolism

In an acceptable aerobic aquatic metabolism study (MRID 4680 1713),the biotransformation of pyrasulfotole was studied in a pond water-sandy loam sediment (water pH 4.8, sediment pH 4.5-5.4, organic carbon 4.1%) from North Carolina and a pond water-silty clay sediment (water pH 7.5, sediment pH 6.9-7.5, organic carbon 0.81%) from Kansas for 131-1 32 days under aerobic conditions. Sediment samples were extracted two to three times with acetonitri1e:water [4: 1 (v:v) for 0- and 1 1-day sandy loam sediments; 9: 1 (v:v) for all other sediment samples] via shaking, then further extracted with the acetonitri1e:water solvent using an Accelerated Solvent Extraction (ASE) system (2 cycles, 80°C, 1,500 psi). In sandv loam svstems (both labels), following application of [14c]- pyrasulfotole to the water layer, I4c-residuespartitioned from the water layer to the sediment with average (n =2) distribution ratios (water:sediment) of ca. 100: 1 at day 0, 2:1 at 1 1-55days, 1:4 at 81 days and were 1:>lothereafter. [14~]-~yrasulfotole in the total system decreased from a mean 97.6% ofthe ap lied at day 0 to 44.5% at 81 days 

## P, and was 16.3-1 8.2% thereafter. In the water layer, [ C]-pyrasulfotole decreased from a mean 97.6% at day 0 to 61.8-68.3% at 11-55 days, 22.9% at 81 days and was 5.2-5.5% thereafter. In the sediment, [14~]-pyrasulfotole increased from a mean 0.9% at day to 25.0% at 26 days, then decreased to 1 1.l-12.7% at 109-1 32 days. Linear half-life for pyrasulfotole in the total system was 48 days and nonlinear half-life was 69 days. Observed DTS0 values were 55-109 days in the total system. However, these fitted transformation models do not adequately fit the observed dissipation pattern of parent residues. Extractable 14c-residues in the sediment increased from a mean 0.9% ofthe applied at day 0 to a maximum 25.1% at 26 days, then decreased to 11.1 -13.1 % at 109- 132 days. Unextractable 14c-residueswere detected at means of 8.1

### - 15.0%at 1 1-55 days, then sharply increased to 50.7% at 81 days and were 72.6% at studytermination. Pyrasulfotole does not appear to be transforming in this sandy loam system, but rather rapidly partitions from the water to an unextractable sediment-bound phase between Days 55 -

### 81. Pyrasulfotole is therefore considered to be stable under conditions ofthis aerobic aquatic system for the purposes of risk assessment. In siltv clav loam svstems (both labels), following application of [I4c]- pyrasulfotole to the water layer, I4c-residuespartitioned from the water layer to the sediment with average (n =2) distribution ratios (water:sediment) of ca. 100: 1 at day 0,3: 1 at 2 1 days and were 2:1 thereafter. ['4~]-~yrasulfotole dissipated slowly in the total system decreasing from a mean 101.4%ofthe applied at day 0 to 82.3-87.8% at 104-13 1 days. In the water layer, [14~]-pyrasulfotole decreased from a mean 100.9%ofthe applied at day 0 to 63.9% at study termination, while increasing in the sediment from 0.5% to 23.9% at the samerespective intervals. Observed DTS0 values were >13 1 days in the water, sediment and total system. Lineadnonlinear half-lives for pyrasulfotole in the sediment and total system were not determined because levels ofparent inthe sediment were still increasing at study termination, and there was insufficient dissipation of parent in the total system. Hence there is no evidence of degradation for pyrasulfotole in this aerobic aquatic system. For the purposes ofrisk assessment it is considered stable. Extractable I4c-residuesin the sediment increased from a mean 1.O% ofthe applied at day 0 to 24.4% at 131 days. Unextractable 14c-residuesincreased from a mean 0.5% at day 0 to 13.1 % at 104 days and were 10.6%at studytermination.

Anaerobic Aquatic Metabolism

In an acceptable study (MRID 46801 714),the biotransformation ofpheny1-Ul"~-labeled pyrasulfotole was studied in a pond water-silty clay sediment (water pH 7.5, dissolved organic carbon 11.7mg/L; sediment pH 6.6-7.0, organic carbon 1.I%) systems from Kansas for 365 days under anaerobic (static, nitrogen atmosphere) conditions in darkness at 20 

### f 1°C. Following application of ['4~]-pyrasulfotole to the water-sediment systems, 14c-residues partitioned from the water layer to the sediment with average (n = 2) distribution ratios (water:sediment) of 100: 1 at day 0,4:1 at 3 days, 2:1at 10days and were 1:1 thereafter. ['4~]-~yrasulfotole dissipated slowly in the total system decreasing fiom a mean 99.2% ofthe applied at day 0 to 65.1% at 31 days and was 60.4%-65.6% thereafter. In the water layer, '4~-pyrasulfotole decreased from a mean 99.2% at day 0 to 49.7% at 31 days and was 38.3-40.0% at 183-365 days. In the sediment, I4cpyrasulfotole increased to a mean 25.5% at study termination. Levels of ['4~]-pyrasulfotole in the sediment were still increasing at study termination; consequently, calculated half-lives could not be determined. Observed DTS0 values ofpyrasulfotole were between 22 and 3 1 days in the water layer and greater than 365 days in the sediment and total system. Non-first order DT50 and DT90 estimates for the total system were estimated at 6000 and 46000 days, respectively using a multi-compartment non-linear regression model (r2= 0.95). Pyrasulfotole is considered stable in the whole system under these anaerobic aquatic conditions for the purposes ofthis risk assessment. Extractable and unextractable sediment I4c-residuesincreased to maximum

means of 25.5% and 33.9% of applied, respectively, at 365 days. The maximum level of volatilized I4c02 detected at any sampling interval was 2.8% ofthe applied, with volatile I4c-organiccompounds less than 0.1%.

In an acceptable study (MRID 46801 715),thebiotransformation ofpyrazole-3- I4c-labeledpyrasulfotole was studied in a pond water-silty clay sediment (water pH 7.5, dissolved organic carbon 1 1.7mg/L; sediment pH 7.0, organic carbon 1.1%) systems fiom Kansas for 365 daysunder anaerobic (static, nitrogen atmosphere) conditions in darkness at 20 

### f 1 OC. Following application of [14~]-pyrasulfotole to the water-sedimentsystems, 14c-residues partitioned from the water layer to the sediment with average (n = 2) distribution ratios (water:sediment) of 100:1 at day 0,4:1at 3 days, 1:1 at 14-184 days and were 1:2 thereafter. ['4~]-~yrasulfotole dissipated slowly in the total system decreasing from a mean 100.0%ofthe a plied at day 0 to 54.9% at 275 days and was 

# P, 59.7% at 365 days. In the water layer, [ C]-pyrasulfotole decreased fiom a mean 100.0%at day 0 to 49.9% at 17 days and was 37.3% at study termination. In the sediment, ['4~]-pyrasulfotole increased to a mean 22.7% at 63 days and was 19.1-22.9% thereafter. Calculated linear and nonlinear half-lives for pyrasulfotole in the water layer and total system are of limited use given the low correlation coefficient values (r2= <0.45), and the half-lives for pyrasulfotole in the total system were extrapolated significantly beyond the final sampling interval. Sinceconcentrations of [14~]-pyrasulfotole in the sediment remained at steady levels from 63 days posttreatment through study termination, calculated half-lives could not be determined. Observed 

### DTsovalues of pyrasulfotole were between 14and 28 days in the water layer and greater than 365 days in the sediment and total system. Non-first order DT50 and DT90 estimates for the total system were estimated at 722 and 4745 days, respectively using a multi-compartment non-linear regression model (r2= 0.95). For the purposes ofrisk assessment, pyrasulfotole is considered stable in the whole system under these anaerobic aquatic conditions. Extractable sediment I4c-residuesincreased to a maximum mean 22.9% of applied at 120days and were 22.4% at 365 days. Unextractable sediment I4c-residues increased to a maximum mean 36.4% at study termination. Volatilized I4c02 totaled a
mean 1.9% ofthe applied at studytermination, with volatile '4~-organic ompounds 10.1 % at any interval.

Mobility and Persistence



### Batch Equilibrium

In an acceptable study (MRID 46801703), the adsorptiontdesorption characteristics ofpyrasulfotole were studied in definitive experiments using three US soils: a HCB silt loam [ pH 7.7, organic carbon 4.7%], a Pikeville loamy sand [ pH 6.4, organic carbon 1.2%], and a Carlyle silt loam [pH 5.2, organic carbon IS%];two German soils: a clay loam [CL6S, pH 7.5, organic carbon 1.7%] and a sandyloam CSL2.3, pH 6.7, organic carbon 1.1 %I; and a German sediment, Nidda sandy loam [pH 5.8, organic carbon 4.6%], in abatch equilibrium experiment. After 24 hours of equilibration, 55.7-63.3%, 60.3-71.0%, 26.4-32.3%, 30.1-35.2%, 43.9-52.2%, and 50.4- 73.5% ofthe applied [14~]-pyrasulfotole was adsorbed to the HCB silt loam, Pikeville loamy sand, CL6S clay loam, SL2.3 sandy loam, and Carlyle silt loam soils, and the Nidda sandy loam sediment, respectively (reviewer-calculated). Adsorption 

### & values averaged 1.32, 1.77,0.367,0.47,4.25, and 32.9 for the HCB silt loam, Pikeville loamy sand, CL6S clay loam, SL2.3 sandy loam, and Carlyle silt loam soils, and the Nidda sandy loam sediment, respectively; corresponding adsorption 

### &, values averaged 28.1, 148,21.6,42.7,283, and 715. Freundlich adsorption 

### KFvalues were 0.980, 1.20,0.341, 0.386, 3.20, and 15.9 for the HCB silt loam, Pikeville loamy sand, CL6S clay loam,SL2.3 sandy loam, Carlyle silt loam soils, and the Nidda sandy loam sediment, respectively; corresponding Freundlich adsorption 

### KF~~ values were 20.8, 100,20.0,35.1, 213, and 345. At the end ofthe desorption phase, 55.0%, 49.7%, 70.4% 69.0% 65.6%, and 61.l%ofthe applied ['4~]pyrasulfotole desorbed from the HCB silt loam, Pikeville loamy sand, CL6S clay loam, SL2.3 sandy loam, and Carlyle silt loam soils, and the Nidda sandy loam sediment, respectively. Desorption 

### Kd values averaged 2.26, 3.67, 0.923, 1.5 1, 10.4, and 56.6 for the HCB silt loam, Pikeville loamy sand, CL6S clay loam, SL2.3 sandy loam, and Carlyle silt loam soils, and the Nidda sandy loam sediment, respectively; corresponding adsorption 

### &, values averaged 48.2, 306, 54.3, 137,696, and 1230. Freundlich desorption 

### KFvalues were 1.37,2.30, 0.678, 1.13, 8.46, and 30.9 for the HCB silt loam, Pikeville loamy sand, CL6S clay loam, SL2.3 sandy loam, and Carlyle silt loam soils, and the Nidda sandy loam sediment, respectively; corresponding Freundlich desorption 

### KFoc values were 29.2, 192,40, 103, 564, and 672.

Terrestrial Field Dissipation

In an acceptable study (MRID 46801716),soil dissipation/accumulationof pyrasulfotole under US field conditions was conducted in three replicate bare plots and three replicate cropped plots (wheat) ofFarnum loam soil in Kansas. In the bare test plot, the measured zero-time recovery ofpyrasulfotole in the 0- 15cm soil layer was 19.80 ppb

or 63.9% ofthe theoretical based on the target application rate (reviewer-calculated based

on a theoretical day-0 recovery of 3 1pglkg). Pyrasulfotole decreased to 11.20 ppb by 7 days, 6.54 ppb by 14days, 1.36 ppb by 58 days, and was last detected above the LOQ at 0.69 ppb at 257 days post-treatment. Pyrasulfotole was detected at levels below the LOQ in the 15-30 cm soil depth, and was not detected below 30 cm. The major transformation product AE 

### B197555 was detected in the 0-15 cm soil depth at a maximum concentration of 6.15ppb at 4 days (which is equivalent to 8.31ppb parent equivalents or 26.8% ofthe theoretical applied pyrasulfotole based on the target application rate), then decreased to 3.25 ppb by 14 days, was below the LOQ by 58 days, and was not detected by 257 days post-treatment. AE B197555 was not detected below the 0-15 cm soil depth at any sampling intervals. Under field conditions in the bare test plot, pyrasulfotole had a calculated half-life DT50and DT90values for pyrasulfotole in the whole soil column using a double first order regression model were 8.9 and 45 days, respectively (r2= 0.97). Calculated DTSO and DTgO values for the strongly bi-phasic dissipation pattern ofAE B197555 residues in the whole soil column were 17 and 45 days following initial application, respectively (r2

= 0.87). In the bare test plot, residue carryover (i.e., percentage ofthetotal amount of parent equivalent material in the whole soil column relative to Day 0 concentrations) was 4.7% at the beginning ofthe following growing season (i.e., at 257 days post treatment), and 1.2% at the end ofthe study (i.e., 526 days post treatment).

In an acceptable study (MRID 46801717), soil dissipation/accumulation of pyrasulfotole under US field conditions was conducted in three replicate bare plots and three replicate cropped plots (wheat) of clay loam/loam soil in North Dakota. In the test plot, the measured zero-time recovery of pyrasulfotole in the 0-15 cm soil layer was24.4 ppb or 7 1.8%ofthe theoretical based on the target application rate (calculated based on a theoretical day-0 recovery of 34 pglkg). Pyrasulfotole decreased to 1 1.9 ppb by 7 days, 4.0 ppb by 27 days, and was last detected above the LOQ at 0.5 ppb at 377 days posttreatment. Pyrasulfotole was not detected above the LOQ in soil below the 0-15 cm soil depth. Themajor transformation product 

### AE 

### B197555 was initially detected in the 0-1 5 cm soil depth at 1.2 ppb at day 0, increased to a maximum of 13.5 ppb by 7 days (which is equivalent to 18.2 ppb parent equivalents or 53.6% ofthe theoretical applied pyrasulfotole based on the target application rate), then decreased to 5.7 ppb by 27 days, 1.O ppb by 317days, and was below the LOQ by 377 days posttreatment. AE B197555 was not detected below the 0-15 cm soil depth. Under field conditions in the bare test plot, pyrasulfotole had calculated DTS0 and DT90values for pyrasulfotole in the whole soil column were 6 and 44 days, respectively (two compartment non-linear regression model; r2 = 0.96). The calculated DTSO and DTgO values for 

### AE I3197555 in the whole soil column were 25 and 227 days, respectively (two-compartment, non-linear regression model; r2 = 0.8l).Carryover oftotal residues in the soil column was 7.7 and 1.8%ofthe applied pyrasulfotole at the beginning ofthe following growing season (i.e. day 3 17) and at the end ofthe study period (i.e. day 498), respectively, based on observed Day 0 concentrations.

In an acceptable study (MRID 46801718), soil dissipation/accumulation of pyrasulfotole under US field conditions was conducted in three replicate bare plots and three replicate cropped plots (wheat) of sandy loam soil in Washington. In thebare test plot, the measured zero-time recovery ofpyrasulfotole in the 0-15 cm soil layer was 27.18 ppb or 109% ofthe theoretical based on the target application rate (calculated based on a theoretical day-0 recovery of 25 &kg). Pyrasulfotole decreased to 17.5 1 - 18.59ppb by 1-3 days, 12.35 ppb by 7 days, was last detected above the LOQ at 1.10ppb at 28 days, and was not detected following 175 days posttreatment. Pyrasulfotole moved into deeper soil layers over time, reaching the 45-60 cm layer at 28 days, the 75-90 cm layer at 58 days, and the 105-120cm layer by 175 days. Pyrasulfotole was detected in the 15-30, 30-45,45-60,60-75, and 75-90 cm soil layers at maximum concentrations of 3.26 ppb (28 days), 1.84ppb (28 days), 1.99ppb (175 days), 1.24ppb (58 days), and 0.57 ppb (58 days), respectively; residues were detected below the LOQ in the 90-1 05 and 105-120 cm soil layers. The major transformation product AE 

### B197555 was detected in the 0-15

cm soil depth at a maximum of 3.86 ppb at 7 days (which is equivalent to 5.21 ppb parent equivalents or 20.8% ofthe theoretical applied pyrasulfotole based on the target application rate), then decreased to below the LOQ by 28-58 days, and was not detected by 120days posttreatment. 

### AE B197.555 was detected in the 15-30cm soil depth at a maximum concentration of 0.94 ppb at 14 days, in the 30-45 cm soil depth at a maximum of 1.59 ppb at 28 days, and in the 45-60 cm soil depth at a maximum of 0.57 ppb at 28 days. AE B197555 was not detected above the LOQ in soil below the 45-60 cm depth; however, residues were detected below the LOQ to 120 cm, the maximum depth analyzed. Under field conditions in the bare test plot, pyrasulfotole had calculated DTsoand DT9o values for pyrasulfotole in the whole soil column were 6 and 213 days, respectively (two compartment non-linear regression model; r2 =0.94). The calculated half-life valuefor AE B197555 residues in the whole soil column was 42.0 days (first order regression; r2 = 0.94), or an estimated DTsoof49 days following initial application. Carryover of total residues in the soil column was 11.1 and 3.3% ofthe applied pyrasulfotole at the beginning ofthe following growing season (i.e. day 269) and at the end of the study period (i.e. day 526), respectively, based on observed Day 0 concentrations.

In an acceptable study (MRID 46801719), soil dissipation~accumulation of pyrasulfotole under Canadian field conditions was conducted in four replicate bare plots in Saskatchewan (Site I), Manitoba (Site 2), and Ontario (Site 3) on clay loam soils. At Site 1 (Saskatchewan), the measured zero-time recovery ofpyrasulfotole in the 0-7.5 cm soil layer was 65.5 ppb or 58.0% ofthe theoretical based on the target application rate (calculated based on a theoretical day-0 recovery of 113 &kg). Pyrasulfotole decreased to 32.8-37.0 ppb by 7-14 days, 20.2-20.8 ppb by 21-30 days, 6.42 ppb by 120days, and was 1.52-2.13ppb fiom 402 to 449 days posttreatment. Pyrasulfotole was detected at 52.83 ppb in the 7.5-15 cm soil depth, 51.46ppb in the 15- 30 cm depth, and 50.65 ppb in the 30-45 cm depth, and was detected only below the LOQ in the 45-60 cm and 60-75 cm depths. The major transformation product AE B197555 was detected in the 0-7.5 cm soil depth at a maximum of 36.9ppb at 14days (which is equivalent to 49.8 ppb parent equivalents, or 67.3% ofthe total parent equivalents in the soil column at Day 0 after application), ranged from 32.1 to 34.9 ppb from 21 to 56 days, then decreased to 8.63 ppb by 120 days, and was 0.90 ppb at 449 days posttreatment. AE B197555 was detected in the 7.5-15 cm soil depth at a maximum of 4.63 ppb at 120days and in the 15-30cm depth at a maximum of 2.60 ppb at 343 days. AE B197555 was not detected above the LOQ in soil below the 15-30 cm depth. At Site 2 (Manitoba), the measured zero-time recovery ofpyrasulfotole in the 0- 15cm soil layer was 1 12.99ppb or 90.4% ofthe theoretical based on the target application rate (calculated based on a theoretical day-0 recovery of 125 pglkg). Pyrasulfotole decreased to 44.8-56.2 ppb from 7 to 61 days, 16.9ppb by 121 days, 8.34 ppb by 349 days, and was 4.60 ppb at 462 days posttreatment. Pyrasulfotole was detected at 57.53 ppb in the 7.5-15 cm soil depth, 53.5 1ppb in the 15-30 cm depth, and 11.14ppb in the 30-45 cm depth, and was only detected below the LOQ in the 45-60 cm depth. The major transformation product AE B197555 was detected in the 0-7.5 cm soil depth at a maximum of 26.7 ppb at 29 days (which is equivalent to 36.1 ppb parent equivalents, or 29.0% ofthe total parent equivalents in the soil column at Day 0 after application), decreased to 16.1 ppb by 6 1days, and ranged from 1.17 to 1.80 ppb fiom 121to 462 days posttreatment. AE 

### B 197555 was detected in the 7.5-15 cm soil depth at a maximum of 3.40ppb at 7 days and was not detected above the LOQ in soil below the 7.5-15 cm depth, but was detected at levels below the LOQ in all soil depths analyzed (0-75 cm) at 462 days posttreatment. At Site 3 (Ontario), the measured zero-time recovery ofpyrasulfotole in the 0-15

cm soil layer was 58.1 ppb or 63.1% of the theoretical based on the target application rate (calculated based on a theoretical day-0 recovery of 92 @kg). Pyrasulfotole decreased to 32.4ppb by 14 days, 20.4 ppb by 30 days, 4.91 ppb by 139 days, and was 0.75 ppb at 458 days posttreatment. Pyrasulfotole was detected at 14.10ppb in the 7.5-15 cm soil depth and was detected below the LOQ in the 15-30, 30-45,45-60, and 60-75 cm depths. Themajor transformation product AE 

### B197555 was detected in the 0-7.5 cm soil depth at a maximum of 27.8 ppb at 14days (which is equivalent to 37.6 ppb parent equivalents, or 56.7% ofthe total parent equivalents in the soil column at Day 0 after application), then decreased to 15.7 ppb by 30 days, 5.20ppb by 56 days, and was last detected above the LOQ at 0.85 ppb at 350 days posttreatment. 

### AE B197555 was detected in the 7.5-15 cm soil depth at a maximum of 2.40 ppb at 7 days and in the 15-30cm depth at a maximum of 1.01ppb at 30 days, and was detected at levels below the LOQ in the 30-45,45-60, and 60-75 cm depths. Under field conditions at Site 1 (Saskatchewan), pyrasulfotole had a calculated DT50and DT90values for whole-soil column pyrasulfotole residues were 10and 260 days, respectively (2 compartment non-linear model, 

### $ =0.86). The calculated half-life value for 

### AE B 197555 residues in the whole soil column was 121.6 days 

## (?
= 0.86), or an estimated DTS0 of 136 days following initial application. Under field conditions at Site2 (Manitoba), pyrasulfotole had a calculated DT50 and DTqO values for whole-soil column pyrasulfotole residues were 9.2 and 53 1 days, respectively (2 compartment non-linear model, r2 =0.89). The calculated half-life value for 

### AE B197555 residues in the whole soil column was 35.0 days (r2= 0.82), or an estimated DTsoof 64 days following initial application. Under field conditions at Site 3 (Ontario), pyrasulfotole had a calculated DTsoand DT90values for whole-soil column pyrasulfotole residues were 1 8 and 178 days, respectively (2 compartment non-linear model, r2 = 0.96). The calculated half-life value for AE B197555 residues in the whole soil column was 26.8 days (r2= 0.94), or an estimated DTSo of41 days following initial application. Carryover ofresidues at the start of the following growing season (i.e., at 343-350 days post treatment), was 37.2%, 18.9%and 8.9% of the applied pyrasulfotole for sites in Saskatchewan, Manitoba and Ontario respectively (the majority of residues were detected

asparent at all sites;total parent-equivalent residues in the soil column were compared to observed levels at Day 

### 0). By the end ofthe study period (i.e., 449-462 days post treatment), 13.7, 16.2and 2.0% of the applied pyrasulfotole was present in the Saskatchewan, Manitoba and Ontario sites, respectively.

### APPENDIX C: PRZMIEXAMS Output Data from the ND Wheat, OR Wheat, and 

### TX Wheat Scenarios

ND Wheat

stored as NDwheat.out Chemical:pyrasulfotole PRZM environment:NDwheatC.txt modified Satday, 12 October2002 at 15:15:08 EXAMS environment:pond298.e~~modified Thuday,29 August 2002 at 15:33:30 Mettile: w14914.dvf modified Wedday, 3 July 2002 at 08:05:52 Water segment concentrations(ppb)

Year 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 Peak 0.1961 0.8606 1.138 1.596 1.703 1.839 2.005 2.163 2.47 2.719 3.035 3.182 3.317 3.552 4.168 4.215 4.524 4.916 5.106 5.238 5.79 5.886 6.088 6.615 6.935 7.2 14 7.472 7.762 7.992 8.339

Sorted results Prob. Peak 96 hr 0.032258064516129 0.064516129032258 1 0.0967741935483871 0.129032258064516 0.16 1290322580645 0.193548387096774 0.22580645 1612903 0.258064516129032 0.290322580645161 0.32258064516129 5.79 0.354838709677419 0.3870967741 93548 0.4 19354838709677 0.45 1612903225806 0.48387096774 1936 21 Day 0.1948 0.8538 1.132 1.586 1.7 1.837 2.001 2.161 2.466 2.715 3.029 3.18 3.316 3.549 4.157 4.2 12 4.519 4.907 5.103 5.237 5.778 5.884 6.085 6.603 6.931 7.209 7.47 7.758 7.99 8.333

21 Day 8.339 7.992 7.762 7.472 7.214 6.935 6.615 6.088 5.886 5.788 5.238 5.106 4.916 4.524 4.215 60 Day 0.1927 0.8487 1.128 1.572 1.699 1.835 1.996 2.16 2.461 2.708 3.025 3.179 3.316 3.546 4.141 4.208 4.5 13 4.896 5.099 5.237 5.764 5.881 6.082 6.587 6.926 7.206 7.466 7.754 7.988 8.325

60 Day 8.338 7.991 7.761 7.472 7.2 13 6.934 6.6 12 6.088 5.886 5.778 5.238 5.105 4.915 4.523 4.215 90 Day 0.1915 0.8427 1.126 1.57 1.698 1.835 1.994 2.159 2.458 2.705 3.02 1 3.178 3.315 3.544 4.132 4.206 4.509 4.89 5.097 5.236 5.756 5.879 6.08 6.578 6.923 7.203 7.464 7.75 1 7.987 8.322

90 Day 8.333 7.99 7.758 7.47 7.209 6.931 6.603 6.085 5.884 5.764 5.237 5.103 4.907 4.519 4.2 12 Yearly 0.104 0.5763 0.9952 1.365 1.637 1.776 1.926 2.088 2.323 2.599 2.889 3.098 3.257 3.435 3.854 4.159 4.38 4.712 4.994 5.173 5.542 5.81 1 5.989 6.355 6.765 7.073 7.343 7.595 7.876 8.177

Yearly 8.325 7.988 7.754 7.466 7.206 6.926 6.587 6.082 5.881 5.756 5.237 5.099 4.896 4.513 4.208Year 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 Peak 0.1828 0.4642 0.7163 0.865 1.108 1.263 1.455 1.795 2.305 2.5 12 2.808 2.994 3.177 3.46 3.658 3.771 3.963 4.202 4.63 4.773 5.155 5.294 5.521 5.755 5.945 6.09 6.364 6.53 1 6.794 7.02

Sorted results Prob. Peak 96 hr 0.0322580645 16129 0.0645 161290322581 0.0967741935483871 0.1290322580645 16 0.16 1290322580645 0.193548387096774 0.22580645 1612903 0.258064516129032 0.290322580645161 0.32258064516129 5.155 0.354838709677419 0.387096774193548 0.419354838709677 0.451612903225806 0.483870967741936 0.5 16129032258065 0.548387096774194 0.580645 161290323 0.612903225806452 0.645161290322581 0.67741 935483871 2.5 12 0.709677419354839 0.74 1935483870968 0.774 193548387097 0.806451612903226 0.8387096774 19355 0.870967741935484 21 Day 0.1818 0.4589 0.7141 0.8637 1.105 1.261 1.452 1.791 2.299 2.5 1 2.804 2.991 3.176 3.456 3.656 3.769 3.961 4.201 4.624 4.771 5.152 5.293 5.518 5.753 5.943 6.089 6.361 6.529 6.79 7.0 17

21 Day 7.02 6.794 6.531 6.364 6.09 5.945 5.755 5.521 5.294 5.154 4.773 4.63 4.202 3.963 3.771 3.658 3.46 3.177 2.994 2.808 2.5 12 2.305 1.795 1.455 1.263 1.108 0.865 60 Day 0.1763 0.456 0.7097 0.8574 1.093 1.252 1.45 1.784 2.294 2.507 2.801 2.989 3.172 3.437 3.652 3.767 3.957 4.175 4.616 4.755 5.148 5.289 5.512 5.749 5.937 6.087 6.295 6.521 6.775 7.013

60 Day 7.019 6.793 6.53 6.363 6.09 5.944 5.755 5.52 5.293 5.152 4.773 4.629 4.202 3.962 3.77 3.657 3.46 3.177 2.993 2.807 2.51 2.304 1.795 1.454 1.262 1.107 0.8647 90 Day 0.1664 0.449 0.6821 0.84 17 1.063 1.238 1.435

90 Day 7.017 6.79 6.529 6.361 6.089 5.943 5.753 5.518 5.293 5.148 4.771 4.624 4.201 3.961 3.769 3.656 3.456 3.176 2.991 2.804 2.507 2.299 1.791 1.452 1.261 1.105 0.8637 Yearly 0.04935 0.2507 0.5094 0.7396 0.9148 1.133 1.305 1.535 1.917 2.338 2.582 2.843 3.04 3.228 3.491 3.68 3.818 4.013 4.29 4.634 4.868 5.179 5.341 5.565 5.789 5.975 6.134 6.389 6.582 6.836

Yearly 7.013 6.775 6.521 6.295 6.087 5.937 5.749 5.512 5.289 5.144 4.755 4.616 4.175 3.957 3.767 3.652 3.437 3.172 2.989 2.801 2.498 2.294 1.784 1.45 1.252 1.093 0.85740.I 6.5 143 6.5 133 6.5 122 6.4984 6.4762 6.3635 Average ofyearly averages: 3.498961 66666667
Inputs generated by pe4.pl- 8-August-2003

Data used for this run: Output File: OR wheat Mettile: w24232.dvf PRZM scenario: 0RwheatOP.txt EXAMS environment file: pond298.e~~ Chemical Name: pyrasulfotole Description Variable Name Value Units Comments Molecular weight mwt 362.3 glmol Henry's Law Const.henry 3.5e- 14 atm-mA3/mol Vapor Pressure vapr 5.l e-9 torr Solubilitysol 6.9e4 mglL Kd Kd mg/L Koc Koc 122 mg/L Photolysis half-life kdp 0 days Half-life Aerobic Aquatic Metabolism kbacw 0 days Halfife Anaerobic Aquatic Metabolism kbacs 0 days Halfife Aerobic Soil Metabolism asm 439 days Halfife Hydrolysis: pH 7 0 days Half-life Method: CAM 2 integer SeePRZM manual Incorporation Depth: DEPl cm Application Rate: TAPP 0.05 kglha Application Efficiency: APPEFF 0.95 fraction Spray Drift DRFT 0.05 fraction of application rate applied to pond Application Date Date 819 dd/mm or ddimmm or dd-mm or dd-mmm Record 17: FILTRA IPSCND 1 UPTKF Record 18: PLVKRT PLDKRT FEXTRC0.5 Flag for Index Res. Run 1R Pond Flag for runoffcalc. RUNOFFnone none, monthly or total(average of entire run)

TX Wheat

stored asTX wheat.out Chemical: pyrasulfotole PRZM environment: TXwheatOP.txt modified Satday, 12 October 2002 at 16:30:22 EXAMS environment: pond298.e~~modified Thuday, 29 August 2002 at 15:33:30 Metfile: w 13958.dvf modified Wedday, 3 July 2002 at 08:06:24 Water segment concentrations (ppb)

Year 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 Peak 0.3997 0.5369 0.6539 2.123 2.519 2.595 3.07 3.279 3.466 3.807 21 Day 0.3913 0.5326 0.65 1 1 2.093 2.51 1 2.592 3.06 3.274 3.463 3.8 60 Day 0.335 0.5 138 0.648 2.053 2.501 2.588 3.019 3.2 13 3.414 3.79 90 Day 0.245 1 0.4821 0.628 1 1.7 2.398 2.569 2.9 3.167 3.38 1 3.723 Yearly 0.06045 0.385 0.5507 0.901 1 2.061 2.499 2.665 3.052 3.284 3.5 16Sorted results Prob. Peak 96 hr 0.032258064516129 0.0645161290322581 0.0967741935483871 0.129032258064516 0.16 1290322580645 0.193548387096774 0.225806451612903 0.258064516129032 0.290322580645161 0.32258064516129 7.51 0.354838709677419 0.3870967741 93548 0.4 19354838709677 0.45 1612903225806 0.483870967741936 0.5 16129032258065 0.548387096774194 0.580645161290323 0.612903225806452 0.645 16129032258 1 0.677419354838713.807 0.709677419354839 0.74 1935483870968 0.774193548387097 0.806451612903226 0.838709677419355 0.870967741 935484 0.903225806451613 0.935483870967742 0.967741 935483871 21 Day 60 Day 10.73 10.72 10.3 10.3 9.978 9.977 9.88 9.879 9.628 9.626 9.321 9.316 8.575 8.571 7.873 7.873 7.742 7.741 7.509 7.508 7.429 7.427 6.876 6.876 6.785 6.783 6.179 6.179 6.014 6.012 5.738 5.735 5.113 5.112 4.853 4.852 4.687 4.684 4.059 4.058 3.805 3.8 3.466 3.465 3.279 3.278 3.07 3.068 2.595 2.594 2.519 2.518 2.123 2.117 0.6539 0.6533 0.5369 0.5365 0.3997 0.398 90 Day 10.72 10.29 9.976 9.875 9.618 9.301 8.561 7.87 7.738 7.505 7.42 1 6.859 6.774 6.176 6.006 5.723 5.1 1 4.847 4.674 4.055 3.79 3.463 3.274 3.06 2.592 2.51 1 2.093 0.651 1 0.5326 0.39 13

9.9359 Average Yearly 10.68 10.58 10.28 10.21 9.971 9.953 9.855 9.782 9.608 9.526 9.278 9.132 8.54 8.407 7.868 7.841 7.719 7.666 7.482 7.402 7.355 7.244 6.833 6.812 6.737 6.569 6.171 6.134 5.997 5.928 5.703 5.563 5.106 5.043 4.84 4.789 4.66 4.531 4.038 3.985 3.723 3.516 3.414 3.381 3.213 3.167 3.019 2.9 2.588 2.569 2.501 2.398 2.053 1.7 0.648 0.6281 0.5 138 0.482 1 0.335 0.2451

9.8538

: of yearly averages:
Inputs generatedby pd.pl -

Data used for this run: Output File: TX wheat Metfile: w13958.dvfPRZM scenario: TXwheatOP.txt EXAMS environment file: pond298.e~~ Chemical Name: pyrasulfotole Description Variable Name Value Units Comments Molecular weight mwt 362.3 glmol Henry's Law Const.henry 3.5e-14 atm-mA3/mol Vapor Pressure vapr 5.l e-9 torr Solubilitysol 6.9e4 mg1L Kd Kd mg/L Koc Koc 122 mg/L Photolysis half-life kdp 0 days Half-life Aerobic Aquatic Metabolism kbacw 0 days Halfife Anaerobic Aquatic Metabolism kbacs 0 days Halfife Aerobic Soil Metabolism asm 439 days Halfife Hydrolysis: pH 7 0 days Half-life Method: CAM 2 integer See PRZM manual Incorporation Depth: DEPl cm Application Rate: TAPP 0.05 kgha Application Efficiency: APPEFF 0.95 fraction Spray Drift DRFT 0.05 fraction of application rate applied to pond Application Date Date 17/10 ddlmm or ddlmmm or dd-mm or dd-mmm Record 17: FILTRA IPSCND I UPTKF Record 18: PLVKRT PLDKRT FEXTRC 0.5 Flag for Index Res. Run IR Pond Flag for runoff calc. RUNOFFnone none, monthly or total(average of entire run)APPENDIX 

### D: Input Parameters andResults fromT-REX



### BIRDS:

TableD.a. Input Parameters forT-REX

Table D.b. Upper 90th Percentile Kenaga, Chronic Avian Dietary Based Risk Ouotients

Table D.c. Mean Kenaga, Chronic Avian Dietary Based Risk Quotients

I EECs and RQs

Short Grass

NOAEC (PP~) 167 Tall Grass

EEC 3.83 Broadleaf Plants/

RQ 0.023 Fruits/Pods/ Seeds/ Large

EEC 1.62 RQ 0.010 Insects EEC 2.03 Insects RQ 0.012 EEC 0.32 RQ 0.002MAMMALS:

Table D.d. Upper 90th Percentile Kenaga, Chronic Mammalian Dietary Based Risk Quotients

Table D. e. Upper 90th Percentile Kenaga, Chronic Mammalian Dose-Based Risk Quotients (PP~)

50 Size class not used for dietary risk quotientsEECs and RQs



# I EECs and RQs I I I I Size Class (grams)

Table D. f Mean Kenaga, Chronic Mammalian Dietary Based Risk Quotients

I 15 35 1000

Size class not used for dietary risk quotients Short Grass Fruits/Pods/ Seeds/ LargeInsects

Adjusted NOAEL

Table D.g. Mean Kenaga, Chronic Mammalian Dose-Based Risk Quotients EEC 10.80 EEC 0.68

5.49 4.45 1.92 RQ 0.22 Tall Grass

RQ 0.01

Short Grass Broadleaf Plants/ SmallInsects EEC 4.95



# 1 EEC 6.08 RQ 0.10

Tall Grass

EEC 10.30 7.12 1.65

EECs and RQs
I I I I Size Class

(grams) RQ 0.12

RQ 1.87 1.60 0.86 Broadleaf Plants/ SmallInsects

EEC 4.72 3.26 0.76

Adjusted NOAEL RQ 0.86 0.73 0.39 Fruitsffodsl Seeds/ Large Insects

EEC 5.79 4.00 0.93

Short Grass Granivore

RQ 1.05 0.90 0.48 EEC 0.64 0.44 0.10

Tall Grass RQ 0.12 0.10 0.05 EEC 0.14 0.10 0.02 RQ 0.03 0.02 0.01

Broadleaf Plants1 Insects Fruits/Pods/ Seeds/ LargeInsects GranivoreTable D.h. Input Parameters for T-REX

Table D.i. Upper 90th Percentile Kenaga, Chronic Mammalian Dietary Based Risk Quotients

NOAEC (PP~)

0

Table D.j. Upper 90th Percentile Kenaga, Chronic Mammalian Dose-Based Risk Quotients

Size 'lass (grams)

15 3 5

1000 Size class not used for dietaryrisk quotients EECs and RQs

Adjusted NOAEL

23.06 152.78

3.18 Short Grass

EEC 5.52

EECs and RQs RQ 0.44 Tall Grass

Short Grass EEC 2.53 RQ 0.54 BroadleafPlants1 Small Insects

Tall Grass EEC 3.11 FruitsIPodsl Seedsl Large Insects RQ 0.06 EEC 0.35

BroadleafPlants1

Small Insects

EEC insectivores

1000.00

1538.32 RQ 0.01

Fruits/Pods/ Seeds1 Large Insects RQ 0.96 0.82 EEC Grainvores 35.00

3556.56 Granivore

RQ 0.54 0.46

0.25 EEC 0.00 15.00 EEC 0.00 1000.00

1538.32 RQ 0.44 0.37 RQ 0.06 0.05

0.03 EEC 0.07 0.05

0.01 0.20 RQ 0.01 0.01

0.01 I 4395. 0.44 66

### APPENDIX 

### E: TerrPlant Model

Exposure to Terrestrial Plants including Wetlands (August 8,2001;version 1 .O)
Terrestrial plants inhabiting dry and semi-aquatic (wetland) areas may be exposed to pesticides from runoff and/or spray drift. Semi-aquatic areas are low-lying wet areas that may dry up at times throughout the year.

EFED's runoff scenario is (1) based on a pesticide's water solubility and the amount ot pesticide present on the soil surface and its top one inch, (2) characterized as "sheet runoff' (onetreated acre to an adjacent acre) for dry areas, (3) characterized as "channel runoff' 

### (10 acres to a distant low-lying acre) for semi-aquatic or wetland areas, and (4) based on percent runoff values of 0.01,0.02, and 0.05 for water solubilities of <lo, 10-100, and >100 ppm, respectively.

EFED's Spray Drift scenario is assumed as (1) 1 % for ground application, and (2) 5% for aerial, airblast, forced air, and spray chemigation applications. The spray drift ratio used here is in agreement with the policy procedures at the time the worksheet was designed.

Currently, 1)this worksheet is designed to derive the plant exposure concentrations from

a single, maximum application rate only. 2) For pesticide applications with incorporation of depth ofless than 1 inch, the total loading EECs derived for the incorporation method will be same as the unincorporated method.

To calculate RQ values for Non-listed Terrestrial Plants:
Terrestrial Plants Inhabiting Areas Adjacent to Treatment Site:

Emergence RQ =Total Loading to Adjacent Area or EECISeedlingEmergence EC25 Drift RQ = Drift EECNegetative Vigor EC25
Terrestrial Plants Inhabiting Semi-aquatic Areas Adjacent to Treatment Site:

Emergence RQ =Total Loading to Semi-aquatic Area or EECISeedling Emergence EC25 Drift RQ =Drift EECIVegetativeVigor EC25

To calculate RQ values for Listed Terrestrial Plants:
Listed Terrestrial Plants Inhabiting Areas Adjacent to Treatment Site:

Emergence RQ =Total Loading to Adjacent Area or EECISeedling Emergence EC05 Drift RQ =Drift EECIVegetative Vigor EC05 or NOAECListed Terrestrial Plants Inhabiting Semiaquatic Areas Near Treatment Site:

Emergence RQ =Total Loading to Semiaquatic Area or EECISeedling Emergence EC05

Drift RQ =Drift EECNegetative Vigor EC05 or NOAEC

Formulas used to calculate EEC values (8108101 ;version 1.O)

To calculate EECs for terrestrial plants inhabiting in areas adjacent to treatment sites
Un-incorporated Ground Application (Non-granular):

Sheet Runoff =Application Rate (lb ai/A) 

### x Runoff Value Drift =Application Rate (lb ai/A) 

### x 0.01 Total Loading =EEC = Sheet Runoff 

### +Drift

Incorporated Ground Application with Drift (Non-granular):

Sheet Runoff = [Application Rate (lb ai/A)/Incorporation Depth (inch)] 

### x Runoff Value Drift =Application Rate (lb ai1A) 

### x 0.01 Total Loading =EEC = Sheet Runoff 

### +Drift

Un-incorporated Ground Application (Granular):

Sheet Runoff =EEC =Application Rate (lb ai1A) 

### x Runoff Value
Incorporated Ground Application without Drift (Granular):

Sheet Runoff =EEC = [Application Rate (lb ai/A)/Incorportion Depth (inch)]



### x Runoff Value
AerialIAirblastlSpray Chemigation Applications:

Sheet Runoff =Application Rate (lb ai/A) 

### x RunoffValue 

### x Application Efficiency of 0.6

Drift = Application Rate (lb ai1A) 

### x 0.05 Total Loading =EEC = Sheet Runoff 

### + Drift

Runoff Value = 0.01,0.02, or 0.05 when the solubility of the chemical is <loppm, 1 0- 100ppm, or>100ppm, respectively
Incorporation Depth: Use the minimum incorporation depth reported on the label.APPENDIX 

### F: Results from Submitted Eco Toxicity Studies for Pyrasulfotole

ANIMALS SPECIES 

## I ENDPOINT 

## I DURATION 

## I MRID 

## I CLASSIFICATION ( COMMENTS ACUTE TERRESTRUL

Colinus virginiunus

Northern bobwhite quail Colinus virginianus

Northern bobwhite quail Anas platyrhynchos Mallard duck

Wistar rat

Apis mellifera

Honey bee Apis mellifera

Honey Bee

Eisenia foetida

Earthworm

AQUATIC LDso= >2000 mg a.i./kg-bw

= >49 1 1mg a.i./kg diet

LCSo = >5089 mg a.i./kg diet

LD50= >2,000 mg a.i.lkg-bw

LD50= >I20 pg a.l./bee LDso= >75 pg a.i./bee

LCs0/ECs0 = >I000 mg a.i./kg NOAEC = >lo00 mg a.i./kg 14-day

8-day

8-day

14-day

Terrestrial 72-hr

72-hr

14-day

Fish Birds

Oncorhychus mykiss Rainbow trout Lepmis macrochirus

Bluegill sunfish Cyprinodon variegates 4680 17-29

46801 7-30

46017-31

LCso= >96 mg a.i./L

= ~96.5 mg a.i.iL

= >I00 mg a.i./L Acceptable

Acceptable

Acceptable Acute oral test; NOAEL =>2000 mg a.i./kg-bw

Acute dietary test; NOAEC = >49 1 1 mg a.i.lkg diet

Acute dietary; NOAEC = 5089 mg a.i./kg diet Mammals

46801 836

Invertebrates 46801 7-34

468017-35

4680 17-41

96-hr

96-hr

96-hr Acceptable

4680 17-24

46801 7-25

46801 7-26 Acute oral; LOAEL = 500 mglkg-bw (increased incidents of corneal opacity, corneal neovascularization and retinal degeneration)

Acceptable

Acceptable

Acceptable Supplemental

Supplemental

Supplemental

Limit test; static conditions

Limit test; static conditions

Limit test; static conditions Oral toxicity

Contact toxicity; only a solvent control and no negative control was tested Non-guideline (EPA requires 28- day test)SPECIES Sheepshead

minnow ENDPOINT DURATION

Daphnia magna

Crassostrea

virginica Eastern oyster Americamysis bahia Mysid Aquatic 48-hr

96-hr

96-hr ECso= >95.8 mg a.i.1L ECso= >I04 mg a.i..lL

LCSO = 1.1 mg a.i./L MRID

CHRONIC TERRESTRIAL Invertebrates 468017-2 1

4680 17-22

468017-23 CLASSIFICATION

Slight reduction in hatchling weight

Male body-weight gain

Delays ofbalanopreputial and increased corneal opacity (LOAEL

= 26.3 mgikg bwlday in males and 32.6 mglkgbwlday in females) Colinus virginianus

Northern bobwhite quail

Anas platyrhynchos Mallard duck

Wistar rat

AQUATIC COMMENTS

Acceptable

Acceptable

Acceptable Limit test; static conditions

Limit test; flowthrough conditions Static conditions

NOAEC = 205 mg a.i./kg diet LOAEC = 594 mg ai.i.ikg diet NOAEC = 167 mg a.i./kg diet LOAEC = 557 mg a.i./kg diet

NOAEL

-2.5 mglkgbwiday

Fish Pimephales promelas

Fathead minnow

Daphnia magna 22-week

20-week

2-generation

NOAEC = 0.58mg a.i.1L (reduction in total length)

NOAEC = 12.8mg a.i.1L Birds 468017-32

468017-33

Mammals

46801907 Acceptable

Acceptable

Acceptable

35-day

Aquatic 2 1 -day 468017-28 Acceptable Flow-through conditions

Static renewal conditions; ECso= >52.9 mg a.i./L (highest conc. tested) Invertebrates 468017-27 Acceptable

### PLANTS

r SPECIES 

### IENDPOINT 

### 1 DURATION 

### 1 MRID 

### 1 CLASSIFICATION 

### 1 COMMENTS

ACUTE AQUATIC

Lemna gibba G3 Duckweed

Pseudokirchneriella subcapitata Algae Navicula pelliculosa AlgaeAnabaenaflosaquae Algae Skeletonema

co~tatum

Algae TERRESTRLAL Various species; seedling emergence (AE 03 17309 02 SE06)

Various species; seedling emergence (AE 0317309+ Bromo)

Various species; vegetative vigor (AE 0317309 02 SE06)

Various species; vegetative vigor (AE 03 17309+ Bromo) EC50/IC50 = 28 pg a.i.1L

EC5011C50 = 11mg a.i.1L

EC5011C50 = 53 mg a.i./L

EC5dICSo = 45.71 mg a.i./L ECSo/ICSo = 8.3 mg a.i.1L

Monocot: NIA Dicot: EC25

= 0.001 1Ib a.i.1acre NOAEC = 0.000399 lb a.i./acre Monocot: NIA Dicot: EC25

= 0.00025 Ib a.i.1acre NOAEC = 0.00022 lb a.i.1acre Monocot: EC25 = 0.017 lb a.i./acre NOAEC = 0.0125 lb a.i.1acre 

# m: EC25 = 0.0008 1lb a.i.lacre NOAEC = 0.000797 lb

a.i.lacre Monocot: NIA Dlco_t: 7-day

96-hr

96-hr

96-hr

96-hr

21 days

21 day

2 1days

2l days 4680 17- 3 6

46801 7- 37

468017- 38

46801 7- 3 9

468017- 40

468019- 26

468019- 3 6

4680 19- 27

468019- 37 Acceptable

Acceptable

Acceptable

Supplemental

Acceptable

Acceptable

Acceptable

Supplemental

Supplemental Based on frond dry weight Based on cell density and biomass Based on biomass

Based on growth rate

Based on biomass

Based on tomato dry weight

Based on tomato dry weight

Based on:

Monocots - Onion dry weight

Dicots

- Tomato dry weight

Based on cucumber dry weight

### ENDPOINT a.i./acre NOAEC = <0.00012 lb a.i./acre ECos= 0.000016 lb a.i./acre CLASSIFICATION COMMENTS 

# '7APPENDIX 

### G: Input Parameters from AgDRIFT

AgDRIFTE Input Data Summary

Tier: I11 Aerial Application Title: Pyrasulfotole Notes: Fine to Medium Droplet Size Distribution Default values appear when they differ from the Current values.

--Aircraft-- ----------Current----------- ---------- Default-----------
Name Air Tractor AT-401 Type Basic Boom Height ( ft) 10 Flight Lines 2 0 Wing Type Fixed-Wing Semispan ( ft) 24.5 Typical Speed (mph) 119.99 Biplane Separation (ft) 0 Weight (lbs) 6000 Planform Area (ft2) 294 Propeller RPM 2000 Propeller Radius ( f t) 4.5 Engine Vert Distance (ft) -1.2 Engine Fwd Distance (ft) 11.9

-Drop Size Distribution 1- ----------Current----------- ---------- Default-----------
Name ASAE Fine to Medium
TYP e Basic Drop Categories # Diam (um) Frac Diam (urn) Frac 1 10.77 0.0010 2 16.73 0.0003 3 19.39 0.0007 4 22.49 0.0003 5 26.05 0.0007 6 30.21 0.0010 7 35.01 0.0010 8 40.57 0.0020 9 47.03 0.0033 10 54.50 0.0053 11 63.16 0.0067 12 73.23 0.0090 13 84.85 0.0133 14 98.12 0.0223 15 113.71 0.0330 16 131.73 0.0393 17 152.79 0.0480 18 177.84 0.0647 19 205.84 0.0830 2 0 238.45 0.1147 2 1 276.48 0.1283 2 2 320.60 0.1380 2 3 372.18 0.1127 2 4 430.74 0.0640--Nozzle Distribution-- ----------Current----------- ---------- Default-----------
Name Nozzles for Air Tractor A... TYPe Basic Horiz Distance Limit (%) 0 Boom Length (%) 76.3 Nozzle DSD & Locations # DSD H(ft) V(ft) F(ft) DSD H(ft) V(ft) F(ft)
1 1 -18.7 0 0 2 1 -17.79 0 0 3 1 -16.87 0 0 4 1 -15.96 0 0 5 1 -15.05 0 0 6 1 -14.14 0 0 7 1 -13.22 0 0 8 1 -12.31 0 0 9 1 -11.4 0 0 10 1 -10.49 0 0 11 1 -9.58 0 0 12 1 -8.66 0 0 13 1 -7.75 0 0 14 1 -6.84 0 0 15 1 -5.93 0 0 16 1 -5.02 0 0 17 1 -4.1 0 0 18 1 -3.19 0 0 19 1 -2.28 0 0 2 0 1 -1.37 0 0 2 1 1 -0.456 0 0 2 2 1 0.456 0 0 23 1 1.37 0 0 2 4 1 2.28 0 0 2 5 1 3.19 0 0 2 6 1 4.1 0 0 2 7 1 5.02 0 0 2 8 1 5.93 0 0 2 9 1 6.84 0 0 3 0 1 7.75 0 0 31 1 8.66 0 0 3 2 1 9.58 0 0 3 3 1 10.49 0 0 3 4 1 11.4 0 0 35 1 12.31 0 0 3 6 1 13.22 0 0 37 1 14.14 0 0 38 1 15.05 0 0 39 1 15.96 0 0 4 0 1 16.87 0 0 4 1 1 17.79 0 0--Swath-- ----------Current----------- ---------- Default----------- Swath Width 60 ft Swath Displacement 0.3702 x Swath Width Half Boom No

--Spray Material-- ----------CurrentDefault-----------
Name
TYPe Nonvolatile Rate (lb/ac) Active Rate (lb/ac) Spray Volume Rate (gal/ac) Specific Gravity Evaporation Rate (vm2/degC/sec) Water Basic 0.501 0.2505

--Meteorology-- ----------Current----------- ---------- Default----------- Wind Speed (mph) 10 Wind Direction (deg) -90 Temperature (deg F) 86 Relative Humidity (%) 5 0

--Transport-- ----------current----------- ---------- Default----------- Flux Plane ( ft) 0

--Terrain-- ----------current----------- ---------- Default----------- Surface Roughness (ft) 0.0246

--Advanced-- ----------Current----------- ---------- Default----------- Wind Speed Height ( f t) 6.56 6.56 Max Compute Time (sec) 6 0 0 Max Downwind Dist (ft) 5280 2608.24 Vortex Decay Rate (mph) 1.25 1.25 Aircraft Drag Coeff 0.1 Propeller Efficiency 0.8 Ambient Pressure (in hg) 29.91 29.91

AgDRIFTB Input Data Summary

--General-- Tier: I11 Aerial Application Title: Pyrasulfotole Notes: ~edium to Coarse Droplet Size ~istribution Default values appear when they differ from the Current values.--Aircraft-- ----------Current----------- ---------- Default-..---------
Name Air Tractor AT-401 Type Basic Boom Height ( f t) 10 Flight Lines 2 0 Wing Type Fixed-Wing Semispan (ft) 24.5 Typical Speed (mph) 119.99 Biplane Separation ( f t) 0 Weight (lbs) 60 0 0 Planform Area (ft2) 294 Propeller RPM 2000 Propeller Radius (ft) 4.5 Engine Vert Distance (ft) -1.2 Engine Fwd Distance (ft) 11.9

-Drop Size Distribution 1- ----------Current----------- ---------- Default-----------
Name ASAE Medium to Coarse ASAE Fine to Medium Type Basic Drop Categories Frac Diam (um) Frac Diam (um)--Nozzle Distribution-- ----------Current----------- ---------- Default-----------
Name Nozzles for Air Tractor A... Type Basic Horiz Distance Limit (8) 0 Boom Length (%) 76.3 Nozzle DSD & Locations # DSD H(ft) V(ft) F(ft) DSD H(ft) V(ft) F(ft) 1 1 -18.7 0 0 2 1 -17.79 0 0 3 1 -16.87 0 0 4 1 -15.96 0 0 5 1 -15.05 0 0 6 1 -14.14 0 0 7 1 -13.22 0 0 8 1 -12.31 0 0 9 1 -11.4 0 0 10 1 -10.49 0 0 11 1 -9.58 0 0 12 1 -8.66 0 0 13 1 -7.75 0 0 14 1 -6.84 0 0 15 1 -5.93 0 0 16 1 -5.02 0 0 17 1 -4.1 0 0 18 1 -3.19 0 0 19 1 -2.28 0 0 2 0 1 -1.37 0 0 21 1 -0.456 0 0 22 1 0.456 0 0 2 3 1 1.37 0 0 24 1 2.28 0 0 2 5 1 3.19 0 0 2 6 1 4.1 0 0 2 7 1 5.02 0 0 2 8 1 5.93 0 0--Swath- - ----------Current----------- ---------- Default----------- Swath Width 60 ft Swath Displacement 0.2781 x Swath Width 0.3702

x Swath Width Half Boom No

--Spray Material--

- - Default-------..---
Name Type Nonvolatile Rate (lb/ac) Active Rate (lb/ac) Spray Volume Rate (gal/ac) Specific Gravity Evaporation Rate (pm2/deg C/sec) Water Basic 0.501 0.2505

--Meteorology-- ----------Current----------- ---------- Default----------- Wind Speed (mph) 10 Wind Direction (deg)

- 90 Temperature (deg F) 86 Relative Humidity (%) 5 0

--Transport-- ----------current----------- ---------- Default----------- Flux Plane (ft) 0

--Terrain-- ----------Current----------- ---------- Default----------- Surface Roughness (ft) 0.0246

--Advanced-- ----------Current----------- ---------- Default----------- Wind Speed Height (ft) 6.56 6.56 Max Compute Time (sec) 600 Max Downwind Dist (ft) 5280 2608.24Vortex Decay Rate (mph) 1.25 Aircraft Drag Coeff Propeller Efficiency Ambient Pressure (in hg) 29.91

AgDRIFlW Input Data Summary

--General-- Tier: I Ground Application Title: Pyrasulfotole Notes: Fine to Medium/Coarse Droplet Size Distribution

----------current----------- ---------- Default----------- Application Method Ground Aerial Application Selection High Boom, ASAE Fine to M... ASAE Fine

### APPENDIX 

### H: Federally Listed Species that Co-Occur with Potential Pyrasulfotol Use Sites at the County-Level (Based on LOCATES).
Species that Could Be Potentiallv DIRECTLY Affected bv Pvrasulfotole Use:

Species Common Name:

Allocarya, Calistoga Ambrosia, San Diego Ambrosia, South Texas Aster, Ruth's Golden Avens, Spreading Ayenia, Texas Barberry, Island Barberry, Nevin's Bear-poppy, Dwarf Bedstraw, Island Bird's-beak, Palmate-bracted Bird's-beak, Pennell's Bird's-beak, salt marsh Bird's-beak, Soft Bittercress, Small-anthered Bladderpod, San Bernardino Mountains Bladderpod, Spring Creek Blazing Star, Scrub Blue-star, Kearney's Bluet, Roan Mountain Broom, San Clemente Island Buckwheat, Cushenbury Buckwheat, Ione (incl. Irish Hill) Buckwheat, Steamboat Bush-mallow, San Clemente Island Bush-mallow, Santa Cruz Island Buttercup, Autumn Button-celery, San Diego Cactus, Arizona Hedgehog Cactus, Bakersfield Cactus, Black Lace Cactus, Brady Pincushion Cactus, Knowlton Cactus, Kuenzler Hedgehog Cactus, Nichol's Turk's Head Cactus, Peebles Navajo Cactus, Pima Pineapple Cactus, San Rafael Cactus, Sneed Pincushion Cactus, Star Cactus, Tobusch Fishhook Cactus, Wright Fishhook Campion, Fringed Ceanothus, Coyote Chaffseed, American Checker-mallow, Keck's Checker-mallow, Kenwood Marsh Checker-mallow, Pedate Checker-mallow, Wenatchee Mountains Taxa: Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot No. of Co. Occurrences 1 6 7 2 13 5 2 6 2 2 19 3 I1 7 9 3 2 1 4 4 2 3 1 1 2 2 1 6 9 5 6 1 4 8 8 1 4 3 10 3 10 7 13 2 48 8 3 3 1Clarkia, Pismo Clarkia, Presidio Clarkia, Vine Hill Cliffrose, Arizona Clover, Leafy Prairie Clover, Monterey Clover, Running Buffalo Clover, Showy Indian Coneflower, Smooth Coneflower, Tennessee Purple Coyote-thistle, Loch Lomond Crownscale, San Jacinto Valley Daisy, Willamette Dawn-flower, Texas Prairie (=Texas Bitterweed) Dogweed, Ashy Dropwort, Canby's Dudleya, Santa Clara Valley Evening-primrose, Antioch Dunes Fiddleneck, Large-flowered Flannelbush, Mexican Frankenia, Johnston's Fringe Tree, Pygmy Fringepod, Santa Cruz Island Gerardia, Sandplain Gilia, Hoffmann's Slender-flowered Gilia, Monterey Golden Sunburst, Hartweg's Goldenrod, Short's Goldfields, Burke's Goldfields, Contra Costa Grass, Hairy Orcutt Grass, Sacramento Orcutt Ground-plum, Guthrie's Harebells, Avon Park Harperella Hypericum, Highlands Scrub Ipomopsis, Holy Ghost Jewelflower, California Jewelflower, Tiburon Larkspur, Baker's Larkspur, San Clemente Island Larkspur, Yellow Layia, Beach Leather-flower, Alabama Leather-flower, Morefield's Lessingia, San Francisco Liveforever, Santa Barbara Island Lomatium, Bradshaw's Lomatium, Cook's Loosestrife, Rough-leaved Lousewort, Furbish Lupine, Clover Lupine, Nipomo Mesa Lupine, Scrub Malacothrix, Island Malacothrix, Santa Cruz Island Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot DicotMallow, Kern Manioc, Walker's Manzanita, Del Mar Manzanita, Santa Rosa Island Meadowfoam, Butte County Meadowfoam, Large-flowered Woolly Meadowfoam, Sebastopol Meadowrue, Cooley's Milk-vetch, Applegate's Milk-vetch, Braunton's Milk-vetch, Clara Hunt's Milk-vetch, Coachella Valley Milk-vetch, Coastal Dunes Milk-vetch, Cushenbury Milk-vetch, Holmgren Milk-vetch, Jesup's Milk-vetch, Lane Mountain Milk-vetch, Mancos Milk-vetch, Sentry Milk-vetch, Shivwits Milk-vetch, Triple-ribbed Milk-vetch, Ventura Marsh Mint, Longspurred Mint, Otay Mesa Mint, San Diego Mesa Monardella, Willowy Monkey-flower, Michigan Mountainbalm, Indian Knob Mountain-mahogany, Catalina Island Mustard, Carter's Mustard, Slender-petaled Navarretia, Few-flowered Navarretia, Many-flowered Nitenvort, Amargosa Oxytheca, Cushenbury Paintbrush, San Clemente Island Indian Paintbrush, Soft-leaved Paintbrush, Tiburon Penny-cress, Kneeland Prairie Pennyroyal, Todsen's Penstemon, Blowout Pentachaeta, Lyon's Pentachaeta, White-rayed Phacelia, Clay Phacelia, Island Phlox, Texas Trailing Phlox, Yreka Pinkroot, Gentian Pitcher-plant, Alabama Canebrake Pitcher-plant, Green Pitcher-plant, Mountain Sweet Plum, Scrub Polygala, Lewton's Pondbeny Popcornflower, Rough Poppy, Sacramento Prickly Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot DicotPoppy-mallow, Texas Potentilla, Hickman's Rattleweed, Hairy Reed-mustard, Barneby Reed-mustard, Shrubby Rhododendron, Chapman Ridge-cress (=Pepper-cress), Barneby Rock-cress, Hoffmann's Rock-cress, Large (=Braunls) Rock-cress, McDonald's Rock-cress, Santa Cruz Island Rock-cress, Shale Barren Rock-cress, Small Rosemary, Short-leaved Rush-pea, Slender Sandlace Sand-verbena, Large-fruited Sandwort, Cumberland Sandwort, Marsh Sea-blite, California Snowbells, Texas Spineflower, Howell's Spineflower, Orcutt's Spineflower, Robust Spineflower, Slender-homed Spineflower, Sonoma Stickseed, Showy Stickyseed, Baker's Stonecrop, Lake County Sumac, Michaux's Sunflower, SanMateo Woolly Sunflower, Schweinitz's Taraxacum, California Tarplant, Gaviota Thistle, Chorro creek Bog Thistle, Fountain Thistle, La Graciosa Thistle, Suisun Thonunint, SanMateo Tuctoria, Green's Umbel, Huachuca Water Wallflower, Contra Costa Wallflower, Menzie's Warea, Wide-leaf Watercress, Gambel's Wild-buckwheat, Clay-loving Wire-lettuce, Malheur Wireweed Woodland-star, San Clemente Island Woolly-star, Santa Ana River Woolly-threads, San Joaquin Yerba Santa, Lompoc Ziziphus, Florida Adobe Sunburst, SanJoaquin Amaranth, Seabeach Amphianthus, Little Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot DicotJoint-vetch, Sensitive Locoweed, Fassett's Lupine, Kincaid's Manzanita, Ione Manzanita, Morro Manzanita, Pallid Milk-vetch, Ash Meadows Milk-vetch, Deseret Milk-vetch, Fish Slough Milk-vetch, Heliotrope Milk-vetch, Pierson's Milkweed, Mead's Milkweed, Welsh's Monkshood, Northern Wild Navarretia, Spreading Paintbrush, Ash-grey Indian Paintbrush, Golden Potato-bean, Price's Primrose, Maguire Pussypaws, Mariposa Reed-mustard, Clay Rosemary, Cumberland Roseroot, Leedy's Rush-rose, Island Sandwort, Bear Valley Skullcap, Large-flowered Sneezeweed, Virginia Spineflower, Monterey Spiraea, Virginia Spurge, Hoover's Spurge, Telephus Sunflower, Pecos Sunray, Ash Meadows Tarplant, Otay Tarplant, Santa Cruz Thelypody, Howell's Spectacular Thistle, Pitcher's Thistle, Sacramento Mountains Thornmint, SanDiego Townsendia, Last Chance Twinpod, Dudley Bluffs Whitlow-wort, Papery Wild-buckwheat, Gypsum Wings, Pigeon Yellowhead, Desert Arrowhead, Bunched Bluegrass, Napa Bulrush, Northeastern (=Barbed Bristle) Grass, California Orcutt Grass, Solano Lily, Pitkin Marsh Pondweed, Little Aguja Creek Sedge, White Wild-rice, Texas Grass, Colusa Grass, San Joaquin Valley Orcutt Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot Dicot ~onocot] Monocot Monocot Monocot Monocot Monocot Monocot Monocot Monocot Monocot MonocotPink, Swamp Water-plantain, Kral's Bat, Gray Bat, Indiana Bat, Lesser (=Sanbornls)Long-nosed Bat, Mexican Long-nosed Bat, Ozark Big-eared Bat, Virginia Big-eared Caribou, Woodland Deer, Columbian White-tailed Ferret, Black-footed Fox, SanJoaquin Kit Fox, San Miguel Island Fox, Santa Catalina Island Fox, Santa Cruz Island Fox, Santa Rosa Island Jaguar Jaguarundi, Gulf Coast Jaguarundi, Sinaloan Kangaroo Rat, Fresno Kangaroo Rat, Giant Kangaroo Rat, Morro Bay Kangaroo Rat, SanBernardino Merriam's Kangaroo Rat, Stephens' Kangaroo Rat, Tipton Manatee, West Indian Mountain Beaver, Point Arena Mouse, Alabama Beach Mouse, Choctawhatchee Beach Mouse, Pacific Pocket Mouse, Perdido Key Beach Mouse, Salt Marsh Harvest Ocelot Panther, Florida Pronghorn, Sonoran Rabbit, Pygmy Rabbit, Riparian Brush Sheep, Sierra Nevada Bighorn Shrew, Buena Vista Lake Ornate Squirrel, Carolina Northern Flying Squirrel, Delmarva Peninsula Fox Squirrel, Mount Graham Red Squirrel, Virginia Northern Flying Vole, Amargosa Vole, Florida Salt Marsh Vole, Hualapai Mexican Whale, Finback Whale, Humpback Whale, northern right Whale, Sei Whale, Sperm Wolf, Gray Woodrat, Riparian Bear, Grizzly Bear, Louisiana Black Lynx, Canada Monocot Monocot ~ammal~ Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Marine mml Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Mammal Marine mml Marine mml Marine mml Marine mml Marine mml Mammal Mammal Mammal Mammal MammalMouse, Preble's Meadow Jumping Otter, Northern Sea Otter, Southern Sea Prairie Dog, Utah Seal, Guadalupe Fur Squirrel, Northern Idaho Ground Mammal 24 Marine mml 2 Marine mml 7 Mammal 15 Marine mml 2 Mammal 4 

## ' The monocots included here are associated with aquatic habitat classifications in LOCATES (i.e., Freshwater, TerrestrialiFreshwater, Vernal Pool, orVernal PooliTerrestrial).
2 No attempt was made to eliminate species based onbody size.
Species that Could Be Potentiallv INDIRECTLY Affected 

### bv Pvrasulfotole Use:

Species Common Name:

Abalone, White Ambersnail, Kanab Amphipod, Illinois Cave Amphipod, Noel's Amphipod, Peck's Cave Beetle, American Burying Beetle, Coffin Cave Mold Beetle, Comal Springs Dryopid Beetle, Comal Springs Riffle Beetle, Helotes Mold Beetle, Hungerford's Crawling Water Beetle, Kretschmarr Cave Mold Beetle, Salt Creek Tiger Beetle, Tooth Cave Ground Bobwhite, Masked Butterfly, Behren's Silverspot Butterfly, Callippe Silverspot Butterfly, El Segundo Blue Butterfly, Fender's Blue Butterfly, Karner Blue Butterfly, Lange's Metalmark Butterfly, Lotis Blue Butterfly, Mission Blue Butterfly, Mitchell's Satyr Butterfly, Myrtle's Silverspot Butterfly, Palos Verdes Blue Butterfly, Quino Checkerspot Butterfly, Saint Francis' Satyr Butterfly, SanBruno Elfin Butterfly, Smith's Blue Butterfly, Uncompahgre Fritillary Campeloma, Slender Cavefish, Alabama Cavesnail, Tumbling Creek Chub, Bonytail Chub, Borax Lake Chub, Gila Chub, Humpback Chub, Mohave Tui Chub, Oregon Chub, Owens Tui Taxa: Gastropod Gastropod Crustacean Crustacean Crustacean Insect Insect Insect Insect Insect Insect Insect Insect Insect Bird Insect Insect Insect Insect Insect Insect Insect Insect Insect Insect Insect Insect Insect Insect Insect Insect Gastropod Fish Gastropod Fish Fish Fish Fish Fish Fish Fish No. of Co. Occurrences 7 1 5 4 10 109Chub, Pahranagat Roundtail Chub, Virgin River Chub, Yaqui Cladonia, Florida Perforate Combshell, Southern (=Penitent mussel) Combshell, Upland Condor, California Crane, Mississippi Sandhill Crane, Whooping Crayfish, Cave (Cambarus aculabrum) Crayfish, Nashville Crayfish, Shasta Cui-ui Curlew, Eskimo Cypress, Santa Cruz Dace, Ash Meadows Speckled Dace, Clover Valley Speckled Dace, Independence Valley Speckled Dace, Moapa Darter, Amber Darter, Bluemask (=jewel) Darter, Boulder Darter, Duskytail Darter, Etowah Darter, Fountain Darter, Maryland Darter, Okaloosa Darter, Relict Darter, Vermilion Darter, Watercress Dragonfly, Hine's Emerald Elktoe, Appalachian Fairy Shrimp, Conservancy Fairy Fairy Shrimp, Longhorn Fairy Shrimp, Riverside Fairy Shrimp, San Diego Falcon, Northern Aplomado Fanshell Fern, Aleutian Shield Fly, Delhi Sands Flower-loving Flycatcher, Southwestern Willow Frog, Dusky Gopher (Mississippi DPS) Frog, Mountain Yellow-legged Gambusia, Clear Creek Gambusia, Pecos Gambusia, San Marcos Goby, Tidewater Harvestman, Bee Creek Cave Harvestman, Bone Cave Harvestman, Robber Baron Cave Isopod, Lee County Cave Isopod, Socorro Kidneyshell, Triangular Kite, Everglade Snail Lichen, Rock Gnome Limpet, Banbury Springs Fish Fish Fish Lichen Bivalve Bivalve Bird Bird Bird Crustacean Crustacean Crustacean Fish Bird Conflcycds Fish Fish Fish Fish Fish Fish Fish Fish Fish Fish Fish Fish Fish Fish Fish Insect Bivalve Crustacean Crustacean Crustacean Crustacean Bird Bivalve Ferns Insect Bird Amphibian Amphibian Fish Fish Fish Fish Arachnid Arachnid Arachnid Crustacean Crustacean Bivalve Bird Lichen GastropodLizard, Blunt-nosed Leopard Logperch, Conasauga Logperch, Roanoke Madtom, Pygmy Madtom, Scioto Madtom, Smoky Marstonia, Royal (=Royal Snail) Meshweaver, Braken Bat Cave Minnow, Rio Grande Silvery Mucket, Pink (Pearlymussel) Mussel, Acornshell Southern Mussel, Black (=Curtus' Mussel) Clubshell Mussel, Clubshell Mussel, Coosa Moccasinshell Mussel, Cumberland Combshell Mussel, Cumberland Elktoe Mussel, Cumberland Pigtoe Mussel, Dark Pigtoe Mussel, Dwarf Wedge Mussel, Fine-rayed Pigtoe Mussel, Flat Pigtoe (=Marshall's Mussel) Mussel, Gulf Moccasinshell Mussel, Heavy Pigtoe (=Judge Tait's Mussel) Mussel, Heelsplitter Carolina Mussel, Ochlockonee Moccasinshell Mussel, Oval Pigtoe Mussel, Ovate Clubshell Mussel, Oyster Mussel, Ring Pink (=Golf Stick Pearly) Mussel, Rough Pigtoe Mussel, Scaleshell Mussel, Shiny Pigtoe Mussel, Shiny-rayed Pocketbook Mussel, Southern Clubshell Mussel, Southern Pigtoe Mussel, Speckled Pocketbook Mussel, Winged Mapleleaf Pearlymussel, Alabama Lamp Pearlymussel, Appalachian Monkeyface Pearlymussel, Birdwing Pearlymussel, Cracking Pearlymussel, Cumberland Bean Pearlymussel, Cumberland Monkeyface Pearlymussel, Curtis' Pearlymussel, Dromedary Pearlymussel, Fat Pocketbook Pearlymussel, Green-blossom Pearlymussel, Higgins' Eye 1Pearlymussel, Little-wing

Pearlymussel, Orange-footed Pearlymussel, Pale Lilliput Pearlymussel, Purple Cat's Paw Pearlymussel, Tubercled-blossom Pearlymussel, Turgid-blossom Pearlymussel, White Cat's Paw Pearlymussel, White Wartyback Reptile Fish Fish Fish Fish Fish Gastropod Arachnid Fish Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve Bivalve BivalvePearlymussel, Yellow-blossom Pebblesnail, Flat Pelican, Brown Plover, Piping Poolfish, Pahrump (= Pahrump Killifish) Prairie-chicken, Attwater's Greater Pseudoscorpion, Tooth Cave Pupfish, Ash Meadows Amargosa Pupfish, Comanche Springs Pupfish, Desert Pupfish, Devils Hole Pupfish, Leon Springs Pupfish, Owens Pupfish, Warm Springs Purple Bean Pygmy-owl, Cactus Fermginous Quillwort, Black-spored Quillwort, Louisiana Quillwort, Mat-forming Rabbitsfoot, Rough Rail, California Clapper Rail, Light-footed Clapper Rail, Yuma Clapper Rhadine exilis (ncn) Rhadine infernalis (ncn) Riffleshell, Northern Riffleshell, Tan Riversnail, Anthony's Rock-pocketbook, Ouachita (=Wheeler's pm) Rocksnail, Plicate Salamander, Barton Springs Salamander, California Tiger Salamander, Desert Slender Salamander, Santa Cruz Long-toed Salamander, Shenandoah Salamander, Sonora Tiger Salamander, Texas Blind Salmon, Atlantic Salmon, Chinook (Sacramento River Winter Run) Salmon, Chinook (Upper Columbia River Spring) Salmon, Coho (Central California Coast population) Salmon, Sockeye (Snake River population) Sea turtle, green Sea turtle, hawksbill Sea turtle, Kemp's ridley Seaturtle, leatherback Shiner, Cahaba Shiner, Cape Fear Shiner, Palezone Shiner, Topeka Shrike, San Clemente Loggerhead Shrimp, Alabama Cave Shrimp, California Freshwater Shrimp, Kentucky Cave Skipper, Carson Wandering Skipper, Laguna Mountain Bivalve Gastropod Bird Bird Fish Bird Arachnid Fish Fish Fish Fish Fish Fish Fish Bivalve Bird Ferns Ferns Ferns Bivalve Bird Bird Bird Insect Insect Bivalve Bivalve Gastropod Bivalve Gastropod Amphibian Amphibian Amphibian Amphibian Amphibian Amphibian Amphibian Fish Fish Fish Fish Fish Reptile Reptile Reptile Reptile Fish Fish Fish Fish Bird Crustacean Crustacean Crustacean Insect InsectSnail, Armored Snail, Iowa Pleistocene Snail, Lioplax Cylindrical Snail, Morro Shoulderband Snail, Pecos Assiminea Snail, Snake River Physa Snail, Tulotoma Snail, Utah Valvata Snail, Virginia Fringed Mountain Snake, San Francisco Garter Sparrow, Florida Grasshopper Spider, Government Canyon Cave Spider, Madla's Cave Spider, Robber Baron Cave Spider, Spruce-fir Moss Spider, Tooth Cave Spider, Vesper Cave Spinedace, White River Spineflower, Howell's Spinymussel, James River Spinyrnussel, Tar River Springfish, Hiko White River Springfish, White River Springsnail, Alamosa Springsnail, Bmneau Hot Springsnail, Idaho Springsnail, Koster's Springsnail, Roswell Springsnail, Socorro Squawfish, Colorado Starling, Ponape Mountain Steelhead, (Southern California population) Stickleback, Unarmored Threespine Stimpshell Stork, Wood Sturgeon, Alabama Sturgeon, Pallid Sturgeon, Shortnose Sturgeon, White Sucker, June Sucker, Lost River Sucker, Modoc Sucker, Razorback Sucker, Shortnose Tadpole Shrimp, Vernal Pool Tern, California Least Tern, Interior (population) Least Tern, Roseate Threeridge, Fat (Mussel) Toad, Arroyo Southwestern Toad, Houston Toad, Wyoming Topminnow, Gila (Yaqui) Torreya, Florida Trout, Gila Turtle, Alabama Red-bellied Gastropod Gastropod Gastropod Gastropod Gastropod Gastropod Gastropod Gastropod Gastropod Reptile Bird Arachnid Arachnid Arachnid Arachnid Arachnid Arachnid Fish Dicot Bivalve Bivalve Fish Fish Gastropod Gastropod Gastropod Gastropod Gastropod Gastropod Fish Bird Fish Fish Bivalve Bird Fish Fish Fish Fish Fish Fish Fish Fish Fish Crustacean Bird Bird Bird Bivalve Amphibian Amphibian Amphibian Fish Conf7cycds Fish ReptileVireo, Black-capped Vireo, Least Bell's Warbler (=Wood), Golden-cheeked Warbler (=Wood), Kirtland's Warbler, Bachman's Woodpecker, Ivory-billed Woodpecker, Red-cockaded Bankclimber, Purple Beetle, Delta Green Ground Beetle, Northeastern Beach Tiger Beetle, Puritan Tiger Beetle, Valley Elderbeny Longhorn Butterfly, Bay Checkerspot Butterfly, Oregon Silverspot Caracara, Audubon's Crested Catfish, Yaqui Cavefish, Ozark Chub, Hutton Tui Chub, Slender Chub, Spottin Cypress, Gowen Dace, Blackside Dace, Desert Dace, Foskett Speckled Darter, Bayou Darter, Cherokee Darter, Goldline Darter, Leopard Darter, Niangua Darter, Slackwater Darter, Snail Eagle, Bald Elimia, Lacy Fairy Shrimp, Vernal Pool Fatmucket, Arkansas Fern, Alabama Streak-sorus Fern, American hart's-tongue Frog, California Red-legged Frog, Chiricahua Leopard Gnatcatcher, Coastal California Isopod, Madison Cave Lizard, Coachella Valley Fringe-toed Lizard, Island Night Madtom, Neosho Madtom, Yellowfin Minnow, Devils River Minnow, Loach Moth, Kern Primrose Sphinx Mucket, Orangenacre Murrelet, Marbled Mussel, Alabama Moccasinshell Mussel, Fine-lined Pocketbook Mussel, Heelsplitter Inflated Naucorid, Ash Meadows Owl, Mexican Spotted Owl, Northern Spotted Bird Bird Bird Bird Bird Bird Bird Bivalve Insect Insect Insect Insect Insect Insect Bird Fish Fish Fish Fish Fish Conflcycds Fish Fish Fish Fish Fish Fish Fish Fish Fish Fish Bird Gastropod Crustacean Bivalve Ferns Ferns Amphibian Amphibian Bird Crustacean Reptile Reptile Fish Fish Fish Fish Insect Bivalve Bird Bivalve Bivalve Bivalve Insect Bird BirdPearlshell, Louisiana Plover, Western Snowy Rattlesnake, New Mexican Ridge-nosed Rocksnail, Painted Rocksnail, Round Salamander, Cheat Mountain Salamander, Flatwoods Salamander,Red Hills Salamander, San Marcos Salmon, Chinook (California Coastal Run) Salmon, Chinook (Central Valley Fall Run) Salmon, Chinook (Central Valley Spring Run) Salmon, Chinook (Lower Columbia River) Salmon, Chinook (Puget Sound) Salmon, Chinook (Snake River Fall Run) Salmon, Chinook (Snake River springlsummer) Salmon, Chinook (Upper Willamette River) Salmon, Chum (Columbia River population) Salmon, Chum (Hood Canal Summerpopulation) Salmon, Coho (Southern ORINorthern CA Coast) Salmon, Sockeye (Ozette Lake population) Scrub-Jay, Florida Sculpin, Pygmy Sea turtle, loggerhead Sea turtle, olive ridley Shagreen, Magazine Mountain Shiner, Arkansas River Shiner, Beautiful Shiner, Blue Shiner, Pecos Bluntnose Silverside,Waccamaw Skink, Blue-tailed Mole Skink, Sand Skipper, Pawnee Montane Slabshell, Chipola Smelt, Delta Snail, Bliss Rapids Snail, Chittenango Ovate Amber Snail, Flat-spired Three-toothed Snail, Painted Snake Coiled Forest Snake, Concho Water Snake, Eastern Indigo Snake, Giant Garter Snake, Lake Erie Water Snake, Northern Copperbelly Water Sparrow, San Clemente Sage Spikedace Spinedace, Big Spring Spinedace,Little Colorado Springfish, Railroad Valley Alopecurus, Sonoma Arizona Agave Beargrass, Britton's Bluegrass, San Bernardino Fritillary, Gentner's Grass, Tennessee Yellow-eyed Bivalve Bird Reptile Gastropod Gastropod Amphibian Amphibian Amphibian Amphibian Fish Fish Fish Fish Fish Fish Fish Fish Fish Fish Fish Fish Bird Fish Reptile Reptile Gastropod Fish Fish Fish Fish Fish Reptile Reptile Insect Bivalve Fish Gastropod Gastropod Gastropod Gastropod Reptile Reptile Reptile Reptile Reptile Bird Fish Fish Fish Fish Monocot Monocot Monocot Monocot Monocot MonocotIrisette, White Ladies1-tresses,Canelo Hills Ladies1-tresses, Navasota Lily, Minnesota Trout Lily, Western Onion, Munz's Sedge, Golden Trillium, Persistent Trillium, Relict 'Amole, Cammatta Canyon Amole, Purple Beaked-rush, Knieskern's Brodiaea, Thread-leaved Iris, Dwarf Lake Ladiesf-tresses, Ute Orchid, Eastern Prairie Fringed Orchid, Western Prairie Fringed Pogonia, Small Whorled Sedge,Navajo Steelhead, (California Central Valley population) Steelhead, (Central California Coast population) Steelhead, (Lower Columbia River population) Steelhead, (Middle Columbia River population) Steelhead, (Northern California population) Steelhead, (Snake River Basin population) Steelhead, (South-Central Californiapopulation) Steelhead, (Upper Columbia River population) Steelhead, (Upper Willamette River population) Sturgeon, Gulf Sucker, Santa Ana Sucker, Warner Tortoise, Desert Tortoise, Gopher Trout, Apache Trout, Bull Trout, Bull (ColumbiaRiver population) Trout, Bull (Klamath River population) Trout, Greenback Cutthroat Trout, Lahontan Cutthroat Trout, Little Kern Golden Trout, Paiute Cutthroat Turtle, Bog (Northern population) Turtle, Flattened Musk Turtle, Ringed Sawback Turtle, Yellow-blotched Map Whipsnake (=Striped Racer), Alameda Monocot Monocot Monocot Monocot Monocot Monocot Monocot Monocot Monocot Monocot Monocot Monocot Monocot Monocot Monocot Monocot Monocot Monocot Monocot Fish Fish Fish Fish Fish Fish Fish Fish Fish Fish Fish Fish Reptile Reptile Fish Fish Fish Fish Fish Fish Fish Fish Reptile Reptile Reptile Reptile Reptile