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

OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION PC Code: 000692 DP Barcodes: 3 74622 Date : August 4 , 2010 MEMORANDUM SUBJECT: Tier I Drinki ng Water Assessment for the Section 3 Proposed Registration of

Pyrasulfotole on Sorghum and Grass Grown for Seed TO: Bethany Benbow, Risk Manager Reviewer

Kathryn Montague , Risk Manager Herbicide Branch Registration Division Jennifer Tyler, Risk Assessor Risk Assessment Branch I Health Effects Division FROM: Chuck Peck, Environmental Engineer

Environmental Risk Branch IV Environmental Fate and Effects Division THROUGH: Marietta Echeverria, RAPL

Mark Corbin , Acting Branch Chief E nvironmental Risk Branch IV Environmental Fate and Effects Division Attached is the drinking water exposure assessment for proposed pyrasulfotole use on sorghum and grass grown for seed . If additional refinements are necessary, please contact Chuck Pe ck at ( 703 ) 3 47 - 8 064 or peck.charles @epa.gov.2 

# Drinking Water Exposure Assessment for the Section 3 Proposed Registration of Pyrasulfotole on Sorghum

And Grass Grown for Seed

N N F F F S

C H 3 C H 3
O H C H 3 O O O

Pyrasulfotole (5 - hydrox y - 1,3 - dimethyl - 1 H - py razol - 4 - yl )[2 - (methylsulfonyl) - 4 - (trifluorometh yl )phen yl ]methanone CAS No. 365400 - 11 - 9 Prepared by: Chuck Peck, Environmental Engineer Environmental Risk Branch IV U. S. Environmental Protection Agency Office of Pesticide Programs Environmental Fate and Effects Division Environmental Risk Branch IV 1200 Pennsylvania Ave., NW

Mail Code 7507C Washington, DC 20460 Reviewed by: Marietta Ecehverria, RAPL Mark Corbin , Acting Branch Chief Environmental Risk Branch IV Environmental Fate and Effects Div ision3

1 EXECUTIVE SUMMARY This document reports the drinking water exposure assessment for p yr asulfotole that has been conducted to support the human health risk assessment for the Section 3 proposed new use registration . Py

rasulfotole is a post emerg ence herbicide currently registered for use on wheat, oats, barley

and triticale , with proposed new uses on sorghum and grasses grown for seed . Foliar spray applications , aerial and ground spray application , are being proposed. Tier 1 surface water and g roundwater modeling w ere conducted for the labeled sorghum use of two application s per ye ar, at a rate of 0.0 39 lbs. a.i./A/application and a retreatment interval of 11 day s, as specified by the proposed Huskie TM label (Reg. No. 264 - 1023) . The recommended estimated drinking water concentrations (EDWCs) for the human health risk assessment are in Table 1. There was one environmental degradate, py rasulfotole - benzoic acid (AE 197555), identified in the soil metabolism and terrestrial field dissipation studie s ; however, it is not of toxicological concern (HED’s Human Health Risk Assessment for Proposed Uses on Cereal Grains, dated 6/8/2007) and is not considered in this assessment. Table 1. Tier I EDWCs for pyrasulfotole for ground spray applications to sor ghum Drinking Water Source Model Use rate (lbs ai/A) Acute (ppb) Chronic (ppb) Surface water FIRST 0.0 39 6.9 4.8 Groundwater SCI - GROW 0.039 2.4 2.4 In a previous drinking water assessment (DP Barcode 330817) , EDWCs were estimated using a single ae rial application of 0.045 lb a.i./acre to wheat and barley . Acute and chronic surface water EDWCs were 4.0 and 2.8 μg/L, respectivel y . Acute and chronic gro undwater EDWCs were 1.4 μg/L. 2 PROBLEM FORMULATION This is a Tier I drinking water assessment that uses modeling and available monitoring data to estimate the groundwater and surface water concentrations in drinking water sources (pre - treatment) resulting from pesticide use on sites that are vulnerable. This initial tier screens out chemicals with lo w potential risk and allows OPP to focus resources on more refined risk assessments for chemicals which potentially present more significant risks. This drinking water assessment reports potential exposure concentrations for the human health dietary risk a ssessment and provides a description of how those concentrations were determined. 3 ANALYSIS 3.1 Use Characterization Py rasu l fotole is a post emergence herbicide that is applied as a foliar spray twice a ye ar at a maximum single application rate of 0.039 lb a. i./A on sorghum (via ground) and 0.03 6 lb a.i./A on grass grown for seed (via ground and aerial) . There is one py rasulfotole end - use product being proposed for registration in the United States for use on sorghum and grass grown for seed,4

Huskie TM Herbici de ( Reg. No. 264 - 1023, an emulsifiable concentrate containing 3.3% py rasulfotole) ( Table 2 ). Table 2. Proposed maximum u se p atterns for pyrasulfotole Product (% a.i.) Uses Application methods Maximum

application rate/year 1 Maximum number of

applications/year Huskie Herbicide (3.3%) Sorghum Ground 0.0 39 lb a.i./acre 2

Grasses grown for seed Ground

Aerial 0.03 6 lb a . i . /acre 1 The application rate on the label was converted to lbs a.i./acre based on the following: The formulated product density = 0.3 1 lb s ai / gal ; the formulation is 3.3% pyrasulfotole ; the max application rate of 15 oz of formulated product/acre (grasses grown for seed) and 1 6 oz of formulated product/acre (sorghum) are allowed. 3.2 Environmental Fate and Transport Characterization Py ras ulfotole is expected to be persistent and mobile to moderatel y mobile (FAO classification) in the environment. Major routes of dissipation include microbial degradation in soils, formation of non - extractable residues in soils and sediments, and dilution. Under aerobic conditions py rasulfotole degraded in 3 soil s (loamy sand, silt loam, sandy loam) according to an apparent bi - phasic pattern with observed DT 50 s ranging from 4 - 65 d ay s and observed DT 90 s ranging from >120 - >358 d ay s . A 2 - compartment, 4 - parameter exponential model, also known as Double First Order Parallel (DFOP), was used to fit the data and resulted in modeled DT 50 s ranging from 6 - 63 d ay s and DT 90 s ranging from 208 - 1424 d ay s (MRIDs 46801709, 406801710, 46801711). Degradation products inclu ded p yrasulfotole - benzoic acid (AE 197555), CO 2 and non - extractable residues. Non - extractable residues were identified at maximums of 35 - 62% of applied radioactivity in the 3 soils. The non - extractable residues are uncharacterized and it is uncertain whe ther they consist of degradates of risk concern. Under sterile conditions, however, the formation of non - extractable residues (as well as the formation of CO 2 and the benzoic acid degradate) were negligible. In terrestrial field dissipation studies py ras ulfotole dissipated from the whole soil profile with modeled (DFOP) DT 90 s ranging 44 - 531 d ay s and the amount of parent p yr asulfotole carry over to the following growing season ranged from 4.7 to 37% (MRIDs 46801716, 46801717, 46801718, 46801719). In aqu atic s ys tems, py

rasulfotole is stable to hydroly sis and photoly sis (MRIDs 46801705, 46801706) . In aerobic aquatic metabolism studies, py rasulfotole partitioned to the se diment and formed non - extractable residues but there was no evidence of degradation. Py rasulfotole is also considered stable to microbial degradation in aquatic sy stems (MRID 46801713) and under anaerobic conditions (MRIDs 46801712, 4681714, 46801715). Batch equilibrium studies resulted in organic carbon sorption coefficients (Ko c ) ranging from 20 to 345 ml/g oc with a median value of 68 ml/g oc (MRID 468 01703) . In terrestrial field dissipation studies py

rasulfotole showed variable downward migration in the soil profile under bare soil conditions. In some studies py rasulfot o le w as 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). Since p yrasulfotole has a Kd less than 5 in most soils and is persistent (hydroly sis half

- life greater than 25 weeks, photoly sis half - life greater than 1 week, aerobic soil metabolism half

- life greater than 2 - 3 weeks), not volatile (Henry ’s Law constant less than 10 - 2 atm/m 3 /mol), and shows movement to 45 cm during some field dissipation studies , there is5

indic ation for potential groundwater contamination (Cohen 1984). Depending on soil, site and meteorological conditions py rasulfotole may

be transported off

- site to drinking water sources via runoff, leaching and spray drift . Table 3 summarizes the registrant - submitted environmental fate and transport properties of py rasulfotole. There was one m ajor degradate , py rasul fo tole - benzoic acid (AE 197555) , detected in the aerobic soil metabolism and terrestrial field dissipation studies. However, drinking water exposure to the benzoic acid degradate is not considered of toxicological concern ( HED’s Human Health Risk Assessment for Proposed Uses on Cereal Grains, dated 6/8/2007).

Table 3 Summary of environmental chemistry and fate properti es of pyrasulfotole Param eter Value Reference/Comments Selected Physical/Chemical Parameters PC code 000692 CAS No. 365400 - 11 - 9 Chemical name (5 - hydroxy - 1, 3 - dim ethylpyrazol - 4 - yl)(α,α,α - trifluoro 2 - me syl - p - tolyl)methanone Chemical formula C 5 H 13 Cl 2N Molecular weight 362.3 g/mol Water solubility (20 °C) pH 4 pH 7 pH 9 4.2 g/L

69 g/L 49 g/L MRID 46801702
Vapor pressure 2.7 x 10 - 7 Pa ( 20  C ) 6.8 x 10 - 7 Pa ( 25  C ) MRID 46801702 log K OW pH 4 pH 7 pH 9 0.276

- 1.36

- 1.58 MRID 46801702

Persistence Hydroly sis Stable (pH = 5, 7, 9) MRID 46801705 Photolysis in water Stable MRID 46801706 Photolysis in soil t 1/2 = 227 d ays MRID 46801707 Environmenta l phototransformation half - life based on sunlight expected in Pheonix, AZ (33.26o N) Aerobic s oil metabolism Soil Type DT 50 (d ays ) DT 90

(d ays ) R2 MRIDs 46801709, 46801710,

46801711 2 compartment, 4 parameter exponential model (DFOP) Loamy sand 5.8 74 9 0.977 Silt loam 63 1424 0.998 Sandy loam 23 208 0.990 Anaerobic s oil metabolism Stable MRID 468017126 Table 3 Summary of environmental chemistry and fate properti es of pyrasulfotole Param eter Value Reference/Comments Aerobic a quatic metabolism Stable MRID 46801713 Anaerobic a quatic metabolism Stable MRIDs 46801714, 46801715 Mobility Batch equilibrium S oil Type K f 1 1/N K oc 2 MRID 46801703 Silt loam 0.98 0.93 21 Loamy sand 1.2 0.91 100 Clay loam 0.34 0.98 20 Sandy loam 0.39 0.95 35 Silt loam 3.2 0.93 213 Sandy loam 16 0.83 345 Laboratory volatility NA Volatility not likely based on low v apor pressure Field Dissipation Terrestrial field dissipation Location DT 50 (days) DT 90 (days) % carry over MRIDs 46801716, 46801717, 46801718, 46801719 Kansas 8.9 45 4.7 North Dakota 5.7 44 7.7 Washington 5.7 213 11 Saskatchewan 10 260 37 Manitoba 9.2 531 19 Ontario 18 178 8.9

Bioaccumulation Accumulation in fish, BCF No data Bioaccumulation is not expected based on low

log K ow 1. Units of (mg/kg)/(mg/L) 1/N , where 1/N is the Freundlich exponent. 2. Approximation calculated from the F reundlich coefficient, per standard EFED guidance. 3.3 Drinking Water Exposure Modeling Tier 1 modeling was used to estimate the drinking water exposure for use in the dietary risk assessment of py

rasulfotole . The f

ollowing is a description of the models us ed, the selection of the model input parameters , and a characterization of the output from these simulations. 3.3.1 Models EDWCs were generated using EFED’s standard suite of models. The FQPA Index Reservoir Screening Tool (FIRST) is a surface water model that is used to estimate both acute and chronic potential pesticide concentrations in untreated drinking water. EDWCs from FIRST represent concentrations which might occur from a single 1 - in - 10 - ye ar storm event following the last application of pesticide at a location more vulnerable than most locations in the United States to runoff, regardless of the crop being produced. The model considers reductions in dissolved concentration due to the percentage of the watershed which is cropped (percent7

cropped area - PC A), due to adsorption of pesticide to field soil and to reservoir bottom sediment, due to incorporation of the pesticide at the time of application, due to degradation in soil before washoff to the reservoir, and due to degradation of the pesticide within the water body . Reservoir water concentrations may be increased due to deposition of spray drift into the feeding stream or directly into the reservoir itself. FIRST is designed to mimic a more complex simulation using the linked PRZM3 (Carsel et. al., 19 97) and EXAMS 2.97.7 (Burns et. al., 2000) models, but requires less time and effort to complete. A more detailed description of the index reservoir watershed can be found in Jones et al., 1998. The FIRST model and users manuals may

be downloaded from th e U.S. Environmental Protection Agency (EPA) Water Models web - page. PCAs that account for the maximum area within a watershed that may be planted with the modeled crop are applied to concentrations predicted b y P RZM/EXAMS. Screening Concentration in Ground Water (SCI - GROW v2.3, Jul. 29, 2003) is a regression model used as a screening tool to estimate pesticide concentrations found in ground water used as drinking water. SCI - GROW was developed by fitting a linear model to ground water concentrations with the Relative Index of Leaching Potential (RILP) as the independent variable. The RILP is a function of aerobic soil metabolism and the soil - water partition coefficient. The output of SCI - GROW represents the concentrations of isoxaben residue that might b e expected in shallow unconfined aquifers under sandy soils, which is representative of the ground water most vulnerable to pesticide contamination and likely to serve as a drinking water source. The SCI - GROW model and user’s manual may also be downloaded from the EPA Water Models web - page (USEPA, 2006). 3.3.2 Modeling Approach and Input Parameters Tables 4 and 5 summarize the model input parameter values used in FIRST and SCI GROW, respectively . These parameters were selected in accordance with EFED’s input parameter guidance (Environmental Fate and Effects Division, 200 9 ). To estimate first order half - lives (rate constants) for exposure modeling, the DFOP modeled DT90s were divided b y 3.32 (the ratio between DT50 and DT90 for first order reactions). This is currentl y a provisional method under evaluation by EFED for use in biphasic studies that do not fit the traditional first order linear or nonlinear model, where the observed DT90s extend beyond the study duration, and the estimated half

- lives from the DFOP model tend to be more conservative. An aerobic soil metabolism first order half - life of 439 day s (the upper 90th percentile confidence bound on the mean) was used for surface water modeling with FIRST and the median value, 226 day s, was used for groundwat er modeling with SCIGROW. The soil - water partitioning coefficient used in FIRST and SCIGROW was 20 ml/g oc , the lowest non - sand Koc . The lowest Koc value was used in SCIGROW because there was greater than 3 - fold variability in the available data. Table 4 . FIRST input parameter values for pyrasulfotole applied to sorghum Parameter Value Source Comments Application Rate (lb a.i./A) 0 .0 39 Huskie Herbicide Label ( 3.3 %) Number of Applications 2 Huskie Herbicide Label (3.3%)8

Table 4 . FIRST input parameter values for pyrasulfotole applied to sorghum Parameter Value Source Comments Retreatment Interval (days) 1 1 Huskie Herbicide Label (3.3%) Soil Partitioning Coefficient (K oc ; ml/g oc ) 20 MRID 46801703 low est non - sand value Aerobic Soil Metabolism t 1/2 (d ays ) 439 MRIDs 46801709, 46801710, 46801711 90 th percentile upper confidence bound on the mean where t 1 /2 is estimated by DT90/3.32 Wetted in? No foliar applied Depth of Incorporation (inches) 0 foliar applied Method of Application Ground spray AE 0317309 SE06

Herbicide (4.4%) Percent Cropped Area 0.87 National default Solubility in Water (mg/L) 6 .9 x 10 4 Product chemistry data Aerobic Aquatic Metabolism t 1/2 (d ays ) 0 MRID 46801713 Stable to aquatic metabolism Hydroly sis t 1/2 (d ay s ) 0 MRID 46801705 Stable to hydrolysis Aquatic Photolysis t 1/2 (d ays ) 0 MRID 46801706 Stable to photolysis

Ta ble 5 . SCIGROW input parameter values for pyrasulfotole applied to sorghum . Parameter Value Source Comments Maximum Application Rate (lb a.i./A/application) 0.039 Huskie Herbicide Label (3.3%) Maximum Number of Applications per Year 2 Huskie Herbicid e Label (3.3%) Aerobic Soil Metabolism Half - life (d ays ) 226 MRIDs 46801709, 46801710, 46801711 median value where t 1/2 is estimated by DT90/3.32 Organic Carbon Partition Coefficient (K oc , ml/g oc ) 20 MRID 46801703 Lo west value; > 3x variability in data 3.3.3 Modeling Results The FIRST and SCI - GROW output files are located in Appendix A . Based on the results of these simulations, EFED recommends an acute surface water EDWC of 6.9 μg/L and a chronic EDWC of 4 .8 μg/L for use in the human health risk assessment . These recommendations are based on the use of py rasulfotole on sorghum at an annual application rate9

of 0.0 78 lb a.i./A/year. The recommended EWDC for groundwater is 2 .4 μg/L and is also based on the use of py

rasulfotole on sorghum at the previously st ated rate. 3.4 Monitoring Data Py rasulfotole is not included as one of the anal yt es monitored in U.S. surface and groundwater under the USGS’s National Water Quality Assessment (NAWQA) program ( http://water.usgs.g ov/nawqa) or in surface water or sediment samples collected by California Department of Pesticide Regulation (CDPR) ( http://cdpr.ca.gov/docs/emon/surfwtr/ surfcont.htm ) . 3.5 Drinking Water Tre atment There is no available information on the drinking water treatment effects on py rasulfotole . The EDWCs in this assessment are representative of concentrations in drinking water source water (pre - treatment). For surface water, the conceptual model assumes that a pesticide reaches surface water via spray drift or surface runoff, where it is instantaneously mixed and concentrations are observed in the water body. Py rasulfotole is stable to hydrol ys is. Therefore, py

rasulfotole will not degrade b y h ydroly sis during the time that elapses from drinking water intake through distribution to the first tap. Because of its low Koc values, treatment methods such as sedimentation, flocculation, and activated carbon, are not expected to be effective at removing py rasulfotole . Py

rasulfotole does not degrade due to photoly sis or aerobic aquatic metabolism. Therefore, if ultraviolet light were used as a means of disinfection, degradation of py

rasulfotole would not be expected. Additionally , while unlikely , if an aerobic digester were used in the drinking water treatment train, degradation would not be expected to occur. 4 CONCLUSIONS The estimated concentrations provided in this assessment are conservative estimates of py rasulfotole concentrations in untreated drinking water. A major source of uncertainty is the nature of the non - extractable residues formed during degradation in soils. Non - extractable residues are identified at maximums of 35 - 62% of applied radioactivity in 3 soils. The non extractable residues are uncharacterized and it is uncertain whether they consist of degradates of risk concern. Under sterile conditions these non - extractable s are not formed suggesting that the formation of them is microbially mediated. The Tier I drinking water as sessm ent i s a screening - level assessment based on simplified models and assumptions. The modeling assessment relie s on maximum use patterns and national default PCAs to reflect potential surface and groundwater concentrations. To the extent that actual use patterns are less than the labeled maximums and the location - specific PCAs are less than assumed in this assessment, actual environmental exposures could be lower. As such, if EDWCs exceed levels of concern, refinements can be made to this assessment to acc ount for regional use patterns.10

References Burns, L.A. 2000. Exposure Anal ys is Modeling Sy stem (EXAMS), Environmental Research Laboratory , Office of Research and Development, U.S. Environmental Protection Agency , Athens, GA. R.F. Carsel, J.C. Imhof

f, P.R. Hummel, J.M. Cheplick and J.S. Donigian, Jr. 1997. PRZM - 3, A Model for Predicting Pesticide and Nitrogen Fate in Crop Root and Unsaturated Soil Zones: Users Manual for Release 3.0; Environmental Research Laboratory , Office of Research and Developme nt, U.S. Environmental Protection Agency , Athens, GA. Cohen, S.Z., Creeger, S.M., Carsel, R.F., Enfield, C.G. In “Treatment and Disposal of Pesticide Wastes;” Krueger, R.F., Seiber, J.N., Eds.; ACS Sy mposium Series No. 259, American Chemical Society : Was hington, DC, 1984; pp. 297 - 325. Environmental Fate and Effects Division. 2008 . FIRST (F)IFRA (I)ndex (R)eservoir (S)creening (T)ool. Tier 1 Model for Drinking Water Exposure: User's Manual. http://www.epa.gov/oppefed1/models/water/first_v1_1_1_user_manual.htm Environmental Fate and Effects Division . 200 3 . SCI GROW: Users Manual. Online at: http://www.epa .gov/oppefed1/models/water/#scigrow Environmental Fate and Effects Division. 200 9 . Guidance for Selecting Input Parameters in Modeling the Environmental Fate and Transport of Pesticides, Version 2.1 . U. S. Environmental Protection Agency . Washington, D.C. October 29, 2009. http://www.epa.gov/oppefed1/models/ water/input_parameter_guidance.htm Health Effects Division. 2007. Memorandum from Jennifer Tyler (H ED) to Tracy White (RD), Subject: Py

rasulfotole: Human - Health Risk Assessment for Proposed Uses on Small Cereal Grains. PC Code: 000692. PP#: 6F7059. DP#: 328640. Decision #: 366490. 6/8/2007. Jones, R. D., S. Abel, W. R. Effland, R. Matzner, R. Parker. 1998. An Index Reservoir for Use in Assessing Drinking Water Exposure. Proposed Methods for Basin - scale Estimation of Pesticide Concentrations in Flowing Water and Reservoirs for Tolerance Reassessment. Presentation to FIFRA Science Advisory Panel, June 29 - 30, 1998. Online at: http://www.epa.gov/scipoly /sap/1998/index.htm MRIDs MRID 46801702 Fontaine, L. (2006) Product Chemistry of P yrasulfotole Technical. Project Number: BR/2470, PA03/044, PA05/102. Unpublished study prepared by

Bay er Corp. 323 p.11

MRID 46801703 Maurer, T.; E yri ch, U.; Fliege, R. (2003) Adsorption/Desorption of AE 0317309 on Five Soils and One Sediment. Project Number: CP/02/014, MO/03/012996, MEF/186/03. Unpublished study prepared by

Bay er Cropscience Gmbh. 84 p. MRID 46801705 Ripperger, R. (2004) [Pyrazole - 3 - (Carbon 14)] AE0317309: Hydrol yt ic Degradation. Project Number: 200578, A9072401. Unpublished study prepared by

Bay er Corp. 59 p. MRID 46801706 Ripperger, R.; Mey er, B. (2005) [(Carbon 14) - UL - Phenyl] and [(Carbon 14) - 3 - Py razole] AE 0317309: Phototransformation in Water. Project Number: 200987, A9082401. Unpublished study prepared by

Bay er Corp. 64 p. MRID 46801707 Arthur, E.; Shepherd, J.; Dominic, A. (2004) [Py razole - 3 - (Carbon 14)] AE 0317309: Phototransformation o n Soil. Project Number: 200638, A9082101. Unpublished study prepared by Bay er Corp. 85 p. MRID 46801709 Fliege, R. (2004) [Phen yl - U - (Carbon 14)] - and [Py razole - 3 - (Carbon 14)] - AE 0317309: Aerobic Soil Metabolism in a L oamy Sand Soil of US Origin Under Laboratory Conditions at 25 degrees C. Project Number: MEF/386/03, CB/02/011. Unpublished study prepared by

Bay er Cropscience Gmbh. 129 p. MRID 46801710 Fliege, R. (2004) [Phen yl - U - (Carbon 14)] - and [Py razole - 3 - (Carbon 14)] - AE 0317309: Aerobic Soil Met abolism in a Soil Metabolism in a Silt L oam Soil of US Origin Under Laboratory Conditions at 25 degrees C. Project Number: MEF/387/03, CB/02/012. Unpublished study prepared b y Ba ye r Cropscience Gmbh. 116 p. MRID 46801711 Fliege, R. (2005) [Phen yl - UL - (C arbon 14)] and [Py razole - 3 - (Carbon 14)] AE 0317309: Aerobic Soil Metabolism in a European Soil. Project Number: MEF/05/459, M1251487/8. Unpublished study prepared by

Bay er Ag, Institute of Product Info. & Residue Anal. 108 p. MRID 46801712 Ripperger, R . (2005) [Phenyl - UL - (Carbon 14)] and [Py razole - 3 - (Carbon 14)] AE 0317309: Anaerobic Soil Metabolism. Project Number: 04MEAIP001, MEAIP001. Unpublished study prepared b y Ba ye r Corp. 92 p. MRID 46801713 Allan, J.; Cheung, C. (2006) [Py razol - 3 - (Carbon 14) ] AE 0317309 and [Phenyl - UL - (Carbon 14)] AE 0317309: Aerobic Aquatic Metabolism. Project Number: MEAIM008, A9042104. Unpublished study

prepared by

Bay er Corp. 101 p.12

MRID 46801714 Shepherd, J.; Arthur, E. (2005) [Phenyl - UL - (Carbon 14)] AE 0317309: Anae robic Aquatic Metabolism. Project Number: 200593, A9042102. Unpublished study prepared b y Bay er Corp. 72 p. MRID 468017 1 5 Arthur, E.; Shepherd, J. (2005) [Py razole - 3 - (Carbon 14)] AE 0317309: Anaerobic Aquatic Metabolism. Project Number: 200495, A90421 01. Unpublished study prepared b y Bay er Corp. 71 p. MRID 46801716 Lenz, M. (2006) Terrestrial Field Dissipation of AE 0317309 in Kansas Soil, 2004. Project Number: MEAIY008, AI/002/S05/02. Unpublished study prepared by

Bayer Corp., Agvise Inc. and Diamond Ag Research, Inc. 191 p. MRID 46801717 Lenz, M. (2006) Terrestrial Field Dissipation of AE 0317309 in North Dakota Soil, 2004. Project Number: MEAIY007, AI/002/S05/02. Unpublished study prepared by

Bay er Corp., Agvise Laboratories, and Agvise Rese arch. 188 p. MRID 46801718 Lenz, M. (2006) Terrestrial Field 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. 1 95 p. MRID 468017 19 Bel yk, M. (2006) Terrestrial Field Dissipation of AE 0317309 in Canada, 2003 - 2004. Project Number: 03BCS01, MEAIM004, AI/002/S05/01. Unpublished study prepared by

Bay er Corp., Vaughn Agricultural Research Serv., Ltd. and Ag - Quest Inc . 333 p.13

Appendix A : Input/Output Modeling Files FIRST File RUN No. 1 FOR pyrasulfotole ON sorghum * INPUT VALUES *

-------------------------------------------------------------------- RATE (#/AC) No.APPS & SOIL SOLUBI L APPL TYPE %CROPPED INCORP ONE(MULT) INTERVAL Koc (PPM ) (%DRIFT) AREA (IN)

-------------------------------------------------------------------- 0.039( 0.077) 2 11 20.069000.0 GROUND( 6.4) 87.0 0.0 FIELD AND RESERVOIR HALFLIFE VALUES (DAYS)

-------------------------------------------------------------------- METABOLIC DAYS UNTIL HYDROLYSIS PHOTOLYSIS METABOLIC COMBINED (FIELD) RAIN/RUNOFF (RESERVOIR) (RES. - EFF) (RESER.) (RESER.)

- ------------------------------------------------------------------- 439.00 2 N/A 0.00 - 0.00 0.00 0.00 UNTREATED WATER CONC (MICROGRAMS/LITER (PPB)) Ver 1.1.1 MAR 26, 2008

--------------------------------------- ----------------------------- PEAK DAY (ACUTE) ANNUAL AVERAGE (CHRONIC) CONCENTRATION CONCENTRATION

--------------------------------------------------------------------

6.894 4.794 SCIGROW File SCIGROW VERSION 2.3 ENVIRONMENTAL FATE AND EFFECTS DIVISION OFFICE OF PESTICIDE PROGRAMS U.S. ENVIRONMENTAL PROTECTION AGENCY

SCREENING MODEL FOR AQUATIC PESTICIDE EXPOSURE SciGrow version 2.3 chemical:pyrasulfotole time is 7/29/2010 11:11:15

------------------------------------------------------------------------ Application N umber of Total Use Koc Soil Aerobic rate (lb/acre) applications (lb/acre/yr) (ml/g) metabolism (days)

------------------------------------------------------------------------ 0.039 2.0 0.078 2.00E+01 226.0

------------------------------------------------------------------------ groundwater screening cond (ppb) = 2.36E+00 ************************************************************************