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



### MEMORANDUM

DATE: November 15, 2012

SUBJECT:

FROM:

THRU:

TO: Jose Gayoso, Chemical Review Manager
Kevin Costello, Chief

Risk Management and Implementation Branch 2

Pesticide Reevaluation Division (7508P) OFFICE OF
CHEMICAL SAFETY AND
POLLUTION PREVENTION



### The Environmental Fate and Effects Division (EFED) has completed the preliminary problem

formulation (attached) for the ecological risk, environmental fate, and endangered species ·
assessments to be conducted as part of the Registration Review of foramsulfuron. This

document is intended to provide an overview of what is currently known regarding the

environmental fate and ecological effects associated with foramsulfuron and its degradation products, and outlines uncertainties regarding attributes of the parent compound and its

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

1

### 2 1. INTRODUCTION

Foramsulfuron is a sulfonylurea herbicide used to control annual and perennial grasses and
broadleaf weeds. Foramsulfuron slows or stunts plant growth (or causes ultimate plant death) by limiting amino acid synthesis in plants through in hibition of acetolactate synthase (ALS). The structure of foramsulfuron, as well as the chemical name and other identifiers are provided in
Table 1

.

Table 1. Foramsulfuron Chemical Identifiers

Parameter Identifier

Chemical Structure

Chemical Name N,N-dimethyl-2-[3-(4,6-dimethoxypyrimidin-2-yl)ureidosulfonyl-4]- formylaminobenzamide 2-[3-(4,6-Dimethoxy-2-pyrimidinyl)ureidosulfonyl]-4-(formamido)- N

, N

dimethylbenzamide SMILES COc2cc(OC)nc(NC(=O)NS(=O)(=O)c1ccc(NC=O)cc1C(=O)N(C)C)n2
CAS Number 173159-57-4 Company Code AE F130360



### In addition to the technical product (Reg. No. 264-688), there are four end-use products that
contain foramsulfuron: Revolver Herbicide (Reg. No. 432-1266), Tribute WG (Reg. No. 432- 1519), Tribute Solo WB32 Herbicide (Reg. No. 264-686), and Option ® 

### Corn Herbicide (Reg. No. 264-685). A safener ingredient, isoxadifen-ethyl, is included in some of the formulations (Reg. Nos. 264-686 and 264-685) to protect the spra yed field corn from damage. Tribute Solo
WB32 Herbicide contains an a dditional active ingredient, iodo sulfuron-methyl-sodium. Tribute WG contains two additional active ingredie nts, thiencarbazone-methyl (PC15804) and halosulfuron-methyl (PC 128721). A summary of all the foramsulfuron formulated products is provided in Table 2

.

Table 2. Foramsulfuron Formulated Products

Product EPA Registration
Number Amount Active Ingredient (Product Code)

Tribute Solo WB32
Herbicide 264-686 30.0 % foramsulfuron (122020) 2.0% iodosulfuron-methyl-sodium (122021) Option ® Corn Herbicide 264-685 35.0% foramsulfuron (122020)

Tribute WG 432-1519 19.8% foramsulfuron (122020) 9.9% thiencarbazone-methyl (15804) 30.8% halosulfuron-methyl (128721)

Revolver Herbicide 432-1266 2.34% foramsulfuron (122020)

### 3 Based on the usage report prepared by OPP’s Biological and Economic Analysis Division, less than 20,500 pounds of foramsulfuron is used on corn per year. 1 

### No usage data are available for sod farms or non-agricultural use sites such as residential turf or golf courses. All currently registered uses of fora msulfuron are listed in Table 3

.

1 Screening Level Usage Assessment Jan. 10, 2012.4Table 3. Currently Registered Foramsulfuron UsesCrop/Site(Reg. No.)Timing;ApplicationTypeMethod/EquipmentMaximum SingleApplication RateRangeMaximumApplicationRate PerYear(lb a.i./A)MaximumApplicationNumberPreharvestInterval(days)ReentryInterval(REI)MinimumRetreatmentInterval(days)CommentsField, Sweet,and PopCorn(264-686,264-685)foliar;broadcastaircraft,ground boom0.038 lb a.i./A 0.076245 d (forage)70 d (grain)12 h NSGolf CourseTurf*(432-1266,432-1519)broadcast ground boom 0.0516 lb a.i./A NS NS NA NS NSOne label (432-1519)restricts yearly applicationrates to 0.0792 lb/ai.spottreatmenthandheld 0.0029 lb a.i./galcannot bedeterminedNS NA NS NSOne label (432-1266) limitsthe minimum retreatmentinterval to 7 days.Commercial/IndustrialLawns*(432-1266,432-1519)broadcast ground boom 0.0516 lb a.i./A NS NS NA NS NSOne label (432-1519)restricts yearly applicationrates to 0.0792 lb/ai.spottreatmenthandheld 0.0029 lb a.i./galcannot bedeterminedNS NA NS NSOne label (432-1266) limitsthe minimum retreatmentinterval to 7 days.Ornamentallawns andturf*(432-1266,432-1519)broadcast ground boom 0.0516 lb a.i./A NS NS NA NS NSOne label (432-1519)restricts yearly applicationrates to 0.0792 lb/ai.spottreatmenthandheld 0.0029 lb a.i./galcannot bedeterminedNS NA NS NSOne label (432-1266) limitsthe minimum retreatmentinterval to 7 days.Recreationarea lawns*(432-1266,432-1519)broadcast ground boom 0.0516 lb a.i./A NS NS NA NS NSOne label (432-1519)restricts yearly applicationrates to 0.0792 lb/ai.spottreatmenthandheld 0.0029 lb a.i./galcannot bedeterminedNS NA NS NSOne label (432-1266) limitsthe minimum retreatmentinterval to 7 days.Residentiallawns*(432-1266,432-1519)broadcast ground boom 0.0516 lb a.i./A NS NS NA NS NSOne label (432-1519)restricts yearly applicationrates to 0.0792 lb ai/a.spottreatmenthandheld 0.0029 lb a.i./galcannot bedeterminedNS NA NS NSOne label (432-1266) limitsthe minimum retreatmentinterval to 7 days.*There is uncertainty with the maximum application rate per year for EPA Reg. No. 432-1266.

### 5 1. PREVIOUS RISK ASSESSMENTS

Three ecological risk assessments have been comple ted for foramsulfuron: the new chemical assessment (field corn; D267565; February 25, 2002), a label amendment assessment (corn; D311844; October 3, 2005), and a new use assessment (popcorn, sweet corn; D324203; September 21, 2006). EFED
evaluated these assessments for foramsulfuron in association with th e current toxicity, exposure, and usage information to determine if sufficient data are available and if further updates are needed to support registration review.

Potential direct risk to terrestri al and aquatic vascular and non-v ascular plants from the use of foramsulfuron is expected. There is also the potential for various indirect effects on non-target animal species due to the effects on the plant community (for example, depletion of food sources and habitat). Potential risk was identified from both aerial applic ations and potentially th rough irrigation water that has received foramsulfuron runoff. The major conc lusions presented in the new chemical assessment
for foramsulfuron are summarized in Table 4 and are briefly discussed in the subsections below.

Table 4. Summary of Risk Concerns Identified for Foramsulfuron in Previous Assessments

Birds Mammals Terrestrial
Plants Terrestrial
Inverts Fish Aquatic
Inverts Aquatic
Plants Groundwater
Contamination Persistence Degradates
of Concern

-- -- √

-- -- -- √ √ √

--



### To date, an ecological risk assessment has not been conducted to assess applications made to lawns and golf courses (EPA Reg. Nos. 432- 1266 and 432-1519). At the time of co nsidering the registration of these uses, the ecological exposure and associated pot ential risks from the proposed use on turf were expected to be comparable to the existing uses on corn ( i.e. , application rates and timing are similar). All registered uses will be considered as part of the registration review risk assessment.

Previous Drinking Water Assessments

A drinking water assessment (DWA) was conducted at the time of th e new chemical assessment, and updated with each subsequent new use, as highlighted in Table 5 . The uses assessed include applications made to field, sweet and pop corn. At this time, the Health Effects Division reports no risk concerns associated with dietary exposures resu lting from potential foramsulfuron residues that may occur in drinking water sources. Therefore, a revi sed DWA in support of registration review is not planned at this time; however, this may be recons idered if EPA determines a new DWA is warranted.

Table 5. Foramsulfuron Drinking Water Assessment Summary

Assessment Crop Tier II Surface Water

Peak
Concentration

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

μ g/L (ppb)

D267565/DWA New
Chemical Field Corn 1 1 0.3 0.2

Tier I Groundwater
Peak Concentration

μ g/L (ppb) Yearly Mean Concentration

μ g/L (ppb)

D311844/DWA Label
Amendment Corn 1

0.05 0.05 D324203/DWA New

Use Sweet Corn and Popcorn 1

1. 2 aerial applications per year at 0.0365 lb a.i./a 14 days apart

### 6 Clean Water Act Programs

Foramsulfuron is not identified as a cause of impair ment for any water bodies listed as impaired under section 303(d) of the Clean Water Act. No Total Maximum Daily Load (TMDL) criteria have been developed for foramsulfuron. Aquatic Life Ambient Water Quality Criteria documents or Aquatic life benchmarks have not been published for foramsulfuron.

2. ENVIRONMENTAL FATE AND TRANSPORT

Physical and Chemical Prop erties of Foramsulfuron

The physicochemical properties of foramsulfuron are shown in Table 6 . Based on these properties alone, foramsulfuron is not expected to be volatile or to bioaccumulate. It is highly soluble in water. Solubility has been shown to increase at higher pHs.

Table 6. Selected Physical/Chemical Parameters 

### of Foramsulfuron

Parameter Value Source/Classification

Molecular mass (molecular formula) 452.3 g/mol ( C 17 H 2 O 7 N 6 S) Calculated using EPI Suite



### Vapor pressure (20°C) Less than the detection limit (10 -5 hPa) at 100 °C MRID 45109311



### Aqueous solubility (20  C) 37 mg/L (pH 5) 3290 mg/L (pH 7) 94600 mg/L (pH 9) 45109321



### Log octanol-to-water partition coefficient (log K OW 

### ) -0.82

-0.78 Calculated using EPI Suite
KOWWIN v.1.67 estimate



### Environmental Fate Properties of Foramsulfuron

Environmental fate properties of foramsulfuron are summarized in Table 7 . These parameters have been updated from previous assessments to refl ect the NAFTA degradat ion kinetics guidance. 2 

### The updated kinetic analyses are presented in APPENDIX A . The results are similar to those previously reported in the data evaluation records (DERs). For many st udies, the DERs indicated that foramsulfuron transformation could not always be adequately described using single first order kinetics. This is consistent with the current kinetic analyses.

Foramsulfuron is susceptible to microbial mediat ed degradation in soil as well as in aquatic environments. Hydrolysis of foramsulfuron is pH dependent with the increased hydrolysis occurring under acidic conditions. Photodegrada tion in aquatic environments is not expected for foramsulfuron. No acceptable data are available on the photodegradati on of foramsulfuron in soil. Foramsulfuron is expected to be mobile in soil. In summary, foramsul furon is likely to leach to groundwater and runoff or drift during applicati on to surface water.

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

### 7 Table 7. Environmental Fate Parameters of Foramsulfuron

Parameter Value Source/Classification

Persistence

Hydrolysis half-life (25  C) pH 4: 5 d pH 5: 11 d pH 7: 156 d pH 9: 176 d MRID 45109324/ supplemental 1

Aqueous photolysis half-life (25  C) Stable MRID 45109325/ acceptable

Soil photolysis half-life (25  C) -- no acceptable
data available

Aerobic soil metabolism half-life (25°C) DT50=8.1 days; DT90=85.9 days;

tR IORE = 25.8 d (US, North Carolina loamy sand) MRID 45109714/ Acceptable 4 DT50=10.7 days; DT90=128 days;

tR IORE = 38.6 d (US, Iowa silty clay loam)

Aerobic soil metabolism half-life (20°C) DT50=10 days; DT90=54.4 days;

tR IORE = 16.4 d 2 (EU 3 )

MRID 45109713/ Acceptable DT50=1.3 days; DT90=11.3 days;

tR IORE = 3.4 d (EU 3 )

DT50=3.4 days; DT90=38.6 days;

tR IORE = 11.6 d (EU 3 )

Anaerobic aquatic metabolism half-life (20°C) t 1/2 =37.7 d (total system) 42.4 d (total system w/out hydrolysis)

t 1/2 = 25.8 d (water)

t 1/2 = 28.0 d (water w/out hydrolysis) MRID 45109729/
Reclassified to Supplemental 5

Anaerobic aquatic metabolism half-life (10°C) t 1/2 =72.1 d (total system) DT50=42.8 days; DT90=182 days;

tR IORE = 54.7 (water) MRID 45109730/
Reclassified to Supplemental 5

Aerobic aquatic metabolism half-life [dissipation half-life (25  C) t 1/2 =28.5 d (total system)

t 1/2 =14.8 d (water) 45109728/
Reclassified to supplemental 5

Mobility

Freundlich soil-water partition coefficients (K F ); organic carbon-normalized Freundlich coefficients (K FOC ) 2.6, 0.42,0 .91, 0.31, 1.2 L/kg; 151, 89, 51, 38, 63 L/kg OC MRID 45109723/ Acceptable

Leaching in Outdoor Lysimiters Supports leaching as a possible dissipation route; however, the study suggests that a complete mass balance transfer is unlikely. MRID 45109721/ Supplemental

Field Dissipation

Terrestrial field dissipa tion half-life; leaching depth t 1/2 =11 d (New York)

t 1/2 =13 d (Missouri)

t 1/2 =18 d (west Ontario)

t 1/2 =13 d (east Ontario) MRID 45109722/ supplemental

Prospective Groundwater Study suggests leaching is possible; however,
it indicates that the total mass (foramsulfuron and environmental transformation products) applied is not likely to leach through the soil profile. 45721301



### Fish Bioconcentration

Fish bioconcentration f actor (steady-state); depuration rate -- No data available

### 8 Parameter Value Source/Classification

1. Replicate samples were not prepared and it was not specified if the samples were incubated in the dark.
2. Notable transformation was observed in the sterile control. Hydrolysis is expected to contribute to the transformation rate as the soil pH is ~5. The use of th e tR IORE value from the no n-sterile sample provides a more conservative half-life value than subtracting the tw o SFO rates and then calcula ting the corresponding halflife value. Transformation is be st represented by a two compartment model such as IORE.
3. No soil taxonomic information is provided; therefore, a comparison between the European soils used in this study cannot be made to be representative use sites in the US. In addition, the soil pH reported is slightly acidic. Additional hydrolysis may account for the difference betw een the half-life values calculated for the US and EU
soils.
4. Kinetic analysis is provided in APPENDIX A

. 5. There is a large amount unknown radioactive residues present in the water fractions. There is also a large amount
of non-extracted residues. For thes e reasons, this study has been reclassified to supplemental.



### Transformation Products

Several major foramsulfuron transformation products were reported in the submitted environmental fate studies. These major transformation products as well as a few minor degradates are listed in Table 8
with the maximum amounts of each chemical formed in the various studies. In both of the anaerobic and aerobic aquatic metabolism studies submitted to EPA, a large amount of the applied radioactivity was
either not extracted or not iden tified, a major study deficiency.

A few environmental fate studies, mainly mobility studies, have been submitted for the foramsulfuron transformation products. These data are summarized in Table 9 . The results suggest that foramsulfuron transformation products, AEF153745 a nd AEF130619 are likely as mobile as foramsulfuron in the soil profile; however, AEF092944 is likely less mobile than foramsulfuron in the soil profile.9Table 8. Foramsulfuron Environmental Transformation ProductsCode Name/SynonymChemical NameChemical StructureStudy TypeRef.(MRID)Maximum%AR (day)Final %AR(studylength)MAJORAEF1306194-amino-2-(N-((4,6-dimethoxypyrimidin-2-yl)carbamoyl)sulfamoyl)-N,Ndimethylbenzamide4-amino-2-[3-(4,6-dimethoxypyrimidin-2-yl)ureidosulfonyl]-N,NdimethylbenamideFormula:C16H20N6O6SMW:424.43 g/molHydrolysis (pH 4@ 25 °C)45109324/Supplemental2.6 (10 d, pyrlabel)2.1 (10 d)Hydrolysis (pH 7@ 25 °C)45109324/Supplemental9.1 (30 d, phenyllabel)9.1 (30 d)Hydrolysis (pH 9@ 25 °C)45109324/Supplemental7.6 (30 d, phenyllabel)7.6 (30 d)Aerobic Soil45109714/acceptable10.4 (3 d) 0.3 (366 d)Aerobic Soil45109713/acceptable30.8(1 d) 0.6 (203 d)AnaerobicAquatic45109729/supplemental1.2 (58 d)total system<LOD (365 d)total systemAEF1537454-Formylamino-N,Ndimethyl-2-sulfamoylbenzamideFormula:C10H13N3O4SMW:271.29g/molNHSNH2OONOOHydrolysis (pH 4@ 25 °C)45109324/Supplemental66.3 (10 d) 66.3 (10 d)Hydrolysis (pH 5@ 25 °C)45109324/Supplemental71.3(30d)71.3 (30 d)Hydrolysis (pH 7@ 25 °C)45109324/Supplemental3.3 (30d) 3.3 (30 d)Hydrolysis (pH 9@ 25 °C)45109324/Supplemental4.1 (30d) 4.1 (30 d)Aerobic Soil45109714/acceptable5.0 (0 d) 0.5 (366 d)Aerobic Soil45109713/acceptable7.8 (3 d) 0.6 (203 d)AnaerobicAquatic45109729/supplemental8.2 (112 d)total system<LOD (365 d)total system10Code Name/SynonymChemical NameChemical StructureStudy TypeRef.(MRID)Maximum%AR (day)Final %AR(studylength)AEF0929444,6-dimethoxypyrimidin-2-amine2-amino-4,6-dimethoxypyrimidineFormula:C6H9N3O2MW: 155.15 g/molHydrolysis (pH 4@ 25 °C)45109324/Supplemental79.7 (10 d) 79.7 (10 d)Hydrolysis (pH 5@ 25 °C)45109324/Supplemental83.3(30 d) 83.3 (30 d)Hydrolysis (pH 7@ 25 °C)45109324/Supplemental4.7 (30 d) 4.7 (30 d)Hydrolysis (pH 9@ 25 °C)45109324/Supplemental1.9 (30 d) 1.9 (30 d)Aerobic Soil45109714/acceptable17.8 (63 d) 5.3 (366 d)Aerobic Soil45109713/acceptable16.9 (56 d) 7.0 (203 d)TFD45109722/supplemental5.06 μg/kg (4d) <LOQ (114)F0338795Formula:C16H18N6O7SMW:438.42 g/molNHSNHNHNNOONOOOOHOAnaerobicAquatic45109729/supplemental17.0(226 d) <LOD (365 d)UnknownsAerobic Aquatic45109728/supplemental28.6 (57 d)total system4.6 (57 d)*14.8 (365 d)total system3.5 (365 d)*AnaerobicAquatic45109729/supplemental53.4 (288 d)total system13.8 (112 d)*53.0 (365 d)total system9.0 (112 d)*Non-extractedResiduesAerobic Aquatic45109728/supplemental75.4 (211 d)total system40.4 (365 d)total systemAnaerobicAquatic45109729/supplemental26.0 (288 d)total system26.0 (365 d)total system11Code Name/SynonymChemical NameChemical StructureStudy TypeRef.(MRID)Maximum%AR (day)Final %AR(studylength)MINORAEF1480034-amino-N,N-dimethyl2-sulfamoyl-benzamideFormula:C9H13N3O3SMW:243.28 g/molH2NSNH2ONOOHydrolysis (pH 4@ 25 °C)45109324/Supplemental5.6(10 d) 5.6 (10 d)Hydrolysis (pH 5@ 25 °C)45109324/Supplemental3.0 (30 d) 3.0 (30 d)Aerobic Soil45109714/acceptable2.2 (63 d) 0.8 (366 d)Aerobic Soil45109713/acceptable0.9 (10, 134 d) 0.4 (203 d)AEF00149406-formamido-1,2-benisothiasol-3(2H)-one1, 1-dioxideN-(1,1,3-Trioxo-2,3-dihydro-1H-1l6-benzo[d]isothiazol-6-yl)-formamideFormula:C8H6N2O4SMW:226.21NHSNHOONOOHydrolysis (pH 4@ 25 °C)45109324/Supplemental7.9 (10 d) 7.9 (10 d)Hydrolysis (pH 5@ 25 °C)45109324/Supplemental9.7(30 d) 9.7 (30 d)AEF00010826-amino-1,1-dioxo-1,2-dihydro-1l6-benzo[d]isothiazol-3-one6-amino-1,2-benzisothiasol-3(2H)-one 1,1-dioxide,potassium saltFormula:C7H6N2O3SMW:198.20H2NSNHOOOHydrolysis (pH 4@ 25 °C)45109324/Supplemental1.1 (10 d) 1.1 (10 d)12Code Name/SynonymChemical NameChemical StructureStudy TypeRef.(MRID)Maximum%AR (day)Final %AR(studylength)AEF099095(4,6-Dimethoxypyrimidin-2-yl)-ureaFormula:C7H10N4O3MW:198.18NH2NHNNOOOAerobic Soil45109713/acceptable0.8 (21 d) <LOD (203 d)Boldfont indicates the highest percentage observed for a given transformation product.MW: molecular weight* Largest single unknown; it is unclear if the residues cited are the same.

### 13 Table 9. Environmental Fate Parameters of Foramsulfuron Transformation Products

Transformation
Product Parameter Value Source/
Classification

Mobility

AEF130619 Freundlich soil-water partition coefficients (K F 

### ); organic carbonnormalized Freundlich coefficients (K FOC 

### ) 1.90, 0.36, 0.79, 2.98 L/kg; 63, 44, 40, 144 L/kg OC MRID 45109725/ acceptable



### AEF153745 Freundlich soil-water partition coefficients (K F 

### ); organic carbonnormalized Freundlich coefficients (K FOC 

### ) 0.51, 1.43, 1.49, 0.99 L/kg; 63, 35, 50, 48 L/kg OC MRID 45109724/ acceptable



### AEF092944 Freundlich soil-water partition coefficients (K F 

### ); organic carbonnormalized Freundlich coefficients (K FOC 

### ) 2.47, 2.59, 8.25, 1.05, 1.82, 4.11, 81.30, 16.50 L/kg; 211, 89, 625, 663, 696, 395, 11289, 917 L/kg OC MRID 45109726/ acceptable



### Safener

Isoxadifen-ethyl, the safener included in corn us e formulations (Reg. Nos. 264-686 and 264-685) of foramsulfuron, is reported to be at concentrations a pproximately equivalent to foramsulfuron concentrations; therefore, the field application rate is expected to be the same (0.038 lb a.i./A). Chemical identifiers for isoxadifen-ethyl are included in Table 10 . Limited environmental fate data for isoxadifen-ethyl is provided in
Table 11 . Isoxadifen-ethyl is expected to be slightly mobile and has the potential to bioaccumulate.

Table 10. Isoxadifen-ethyl Chemical Identifiers

Parameter Identifier

Chemical Structure

N O

O O

Chemical Name ethyl 4,5-dihydro-5,5-diphenyl-1,2-oxazole-3-carboxylate ethyl 4,5-dihydro-5,5-diphenyl-3-isoxazolecarboxylate SMILES C1(C(OCC)=O)=NOC(C1)(c1ccccc1)c1ccccc1

CAS Number 163520-33-0



### Table 11. Physical/Chemical Parameters 

### of Isoxadifen-ethyl

Parameter Value Source/Classification

Molecular mass (molecular formula) 295.34 g/mol (C 18 H 17 O 3 N) Calculated using EPI Suite

Vapor pressure (20°C) 6.79 x 10 -5 Pa Calculated using EPI Suite
Modified Grain Method

Aqueous solubility (20  C) 1.26 mg/L MRID 44739133 (algal toxicity study)

### 14 Parameter Value Source/Classification

Log octanol-to-water partition coefficient (log K O W ) 5.66 Calculated using EPI Suite
KOWWIN v.1.67 estimate

Koc 9777 L/kg Calculated using EPI Suite
Kow method

Hydrolysis stable Calculated using EPI Suite



### 3. RECEPTORS

Table 12 and Table 13 provide a summary of the aquatic and terrestrial taxonomic groups, respectively, and the most sensitive surrogate species tested to characteriz e the potential acute and ch ronic ecological effects of foramsulfuron. The tables provide a preliminary overvie w of the potential acute toxi city of foramsulfuron by providing the acute toxicity classifications. Based on the available ecot oxicity information, the organisms facing the greatest hazard are aquatic and terrestrial plants. No toxicity data were submitted or identified in the open literature for the foramsulfuron transformation products. Ho wever, some toxicity data are available from other sulfonylurea chemicals that shar e common degradates, and are disc ussed in detail below.

Table 12. Summary of the Most Sensitive Endpoints from Aquatic Toxicity Studies for Foramsulfuron

Taxonomic

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

measured active ingredient) MRID and
Classification Acute Toxicity
Classification

Freshwater fish 1 Acute Rainbow Trout ( Oncorhynchus mykiss )

TGAI LC 50 = >100 mg a.i./L

Most sensitive endpoint:

none No sublethal effects reported. 45109903 Acceptable Practically
nontoxic

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

TGAI NOAEC = 10.5 mg
a.i./L LOAEC = >10.5 mg
a.i./L

Most sensitive endpoint:

none No sublethal effects reported. 46241301 Acceptable --

Estuarine/Marine
fish Acute Sheepshead
Minnow ( Cyprinodon variegatus )

TGAI LC 50 = >93.6 mg a.i./L

Most sensitive endpoint:

none No sublethal effects reported. 45109927 Acceptable Slightly toxic

Freshwater
invertebrates Acute Water Flea ( Daphnia magna )

TGAI EC 50 = >102.5 mg a.i./L

Most sensitive endpoint:

none No sublethal effects reported. 45109906 Supplemental

Classification
based on water quality deviations
from 850 guideline
recommendations. Practically
nontoxic

### 15 Taxonomic

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

measured active ingredient) MRID and
Classification Acute Toxicity
Classification

Chronic Water Flea ( Daphnia magna )

TGAI NOAEC = 100 mg a.i./L LOAEC = >100 mg
a.i./L

Most sensitive endpoint:

none No sublethal effects reported. 45109907 Acceptable --

Estuarine/Marine
invertebrates Acute –
shell deposition study Eastern Oyster ( Crassostrea virginica )

TGAI EC 50 = 118 mg a.i./L NOAEC = 13.4 mg
a.i./L 45109929 Acceptable Practically
nontoxic

Aquatic plants and algae Nonvascular Freshwater Cyanobacterium (Anabaena flosaquae )

TGAI EC 50 = 3.3 mg a.i./L NOAEC = < 3.0 mg
a.i./L

Endpoint: area under the growth curve. 45109909 Acceptable --

Nonvascular Marine Diatom ( Skeletonema

costatum )

TGAI EC 50 = >105 mg a.i./L NOAEC = <105 mg
a.i./L Endpoint: growth rate 45109930 Acceptable --

Vascular Duckweed ( Lemna gibba )

TGAI EC 50 = 0.00065 mg
a.i./L NOAEC = 0.00036 mg
a.i./L

Endpoint: area under the growth curve. 45109911 Acceptable --

1. Freshwater fish represent surrogat es for aquatic-phase amphibians.

### 16 Table 13. Summary of the Most Sensitive Endpoints fr om Terrestrial Toxicity Studies for Foramsulfuron

Taxonomic

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

measured active ingredient) MRID and
Classification Acute Toxicity
Classification

Birds 1 Acute Bobwhite quail ( Colinus virginianus )

TGAI LD 50 = >2,000 mg/kg-bw Most sensitive endpoint:

none No sublethal effects reported. 45109733 Acceptable Practically
nontoxic 3

Sub-acute dietary Mallard Duck ( Anas platyrhynchos )

TGAI LC 50 = >4438 mg/kg diet Most sensitive endpoint:

none No sublethal effects reported. 45109736 Acceptable Practically
nontoxic 3

Chronic Bobwhite quail ( Colinus virginianus )

TGAI NOAEC = 1000 ppm LOAEC = >1000 ppm

Most sensitive endpoint:

none No sublethal effects reported. 45109901 Supplemental

Chemical was
not dissolved
in carrier for preparation of
food. --

Mammals Acute Oral Laboratory rat ( Rattus norvegicus ) LD 50 = >5,000 mg a.i./kg 45109433 Acceptable Practically
nontoxic 3

Acute
Inhalation Laboratory rat ( Rattus norvegicus ) LC 50 = > 5.04 mg/L 45109435 Acceptable --

Chronic Laboratory rat ( Rattus norvegicus ) NOAEL = 15000 ppm
LOAEL = ND Endpoint: NA 45109616 Acceptable Practically
nontoxic 3

Insects Acute

contact Honey bee ( Apis mellifera L. )

TGAI LD 50 = >1.9 μg a.i./bee
No sublethal effects reported. 45109915 Acceptable Moderately
Toxic 2

Acute Oral Honey bee ( Apis mellifera L. )

TGAI LD 50 = >163 μg a.i./bee
No sublethal effects reported. 45109914 Acceptable Practically
nontoxic 2

Terrestrial plants Vegetative Vigor Dicot – Radish ( Raphanus sativus )

Formulated Corn
Product NOAEC = 0.00005 lbs
a.i./acre
IC 25 = 0.00010 lbs
a.i./acre Endpoint: Mean Weight 45483801 Acceptable --

Monocot – Rye ( Lolium perenne )

Formulated Corn
Product NOAEC = 0.0004 lbs
a.i./acre
EC 25 = 0.0014 lbs
a.i./acre Endpoint: Mean Weight 45483801 Acceptable --

1 Birds represent surrogates for terrest rial-phase amphibians and reptiles.

2 Based on acute contact LD 50 ( μ g a.i./bee) <2 highly toxic; 2-10.99 moderately toxic; ≥ 11 practically non-toxic

3 Acute Oral (avian/mammal): Based on LD 50 (mg/kg) <10 very highly toxic; 10-50 highly toxic; 51-500 moderately toxic; 501-2000 slightly toxic; >2000 practically nontoxic

### 17 Effects of Foramsulfuron on Plant Reproduction

EFED's Plant Technical Team (PTT) conducted an analys is of available SU plant reproduction data from the open literature and the registrant-submitted data for chlorsulfuron and concluded that data from the vegetative vigor guideline (850.4150) st udy are sufficiently protective of poten tial impacts to plant reproduction. Acetolactate synthase (ALS) inhibitors primarily affect metabolically-active meristem tissues. When plants are exposed at a young, vigorously growing lif e-stage, effects are expressed prim arily as inhibition of vegetative growth ( i.e. biomass, shoot length). As plan ts mature these effects are less pronounced. However, as plants enter their reproductive life-stage, the me tabolically active tissue will include flower and seed production. Plants exposed to SU herbicides during the reproductive life stage are likely to ex hibit adverse effects on reproduction, generally expressed as reduced seed number or reduced seed weight. Based on the la test data analysis, these effects are expected to occur at sim ilar concentrations to t hose effects determined in the guideline vegetative vigor studies (850.4150) so further data are not requested at this time.

Degradate Toxicity

Two degradates AEF130619 and F0338795 contain an intact sulfonyl urea (SU) bridge (-NH-CO-NH-SO2-) which has been identified as an important functional structure of SU toxicity thus are considered to have similar toxicity to the parent.

Acute oral toxicity data for AE F092944 (also known as ADMP; and IN J0290) with laboratory rats (LD 50 

### = 836 mg/kg; MRID 47305226) suggest that th is degradate is slightly more toxic than the parent (see Table 13 ) but is considered practica lly non-toxic.

The degradate AEF099095 (also known as DOP urea; IR7825; N-(4,6-diethoxypyrim idin-2-yl)urea); and UPDM) is practically non-toxi c to the laboratory rat (LD 50 

### 677 mg/kg, MRID 47305223) on an acute oral basis. A preliminary review of the available va scular plant toxicity data for this de gradate suggests that it is less toxic to vascular plants than the pare nt (NOAEC >0.3122 lbs/A; MRID 46588504).

There are no toxicity data available for degradate AEF001082 (aminosaccharin); however, data for saccharin suggests similar toxicity to the parent foramsulfuron.

Safener Toxicity

Available data suggest that isoxadifen-ethyl (AEF122006), a safener added to formulations intended for corn use, is highly toxic to the bluegill (MRID 44739131; LC 50 

### = 0.22 mg/L, NOAEC = 0.09 mg/L) and the rainbow trout (MRID 44739130; LC 50 

### = 0.34 mg/L, NOAEC = 0.12 mg a.i./L). Ch ronic toxicity studies including the safener are not available; however, es timated endpoints using ECOSAR (versi on 1.11) result in chronic toxicity concentrations of 8 μg/L for fish and 15 μg/L for invertebrates ( APPENDIX D ). See the Stressors of Concern discussion below, which discusses a cursory analysis c onducted to assess potential ex posure of the safener to aquatic animals.

Ecological Incidents

A search of the Ecological Incident Information System (EIIS) database showed 45 “Probable” foramsulfuron incidents affecting standing corn crop s from direct applications, and im pacting as much as 400 acres. There
were also 22 “Possible” incidents affec ting as much as 1350 acres of corn crops.

In the Incident Data System (IDS) database, registrants reported 33 plant incidents associated with
foramsulfuron use between 2002 and 2011.

### 18 A search of the Avian Incident Moni toring System (AIMS) database did not provide any addi tional incident
data.

4. CONCEPTUAL MODEL

The environmental fate properties of foramsulfuron indicate that direct spra y, spray drift, leaching to groundwater, and runoff represent potent ial transport mechanisms. These path ways may result in a wide range of potential aquatic and terrest rial exposure scenarios.

5. ANALYSIS PLAN

Ecological Risk Assessment



## Stressors of Concern

The exposure assessments will consider the parent, fora msulfuron, as well as the major degradates listed in
Table 8 ( e.g. , AEF130619 and F0338795) using a total toxic residue approach. The transformation products AEF130619 and F0338795 contain an intact sulfonyl urea (SU) bridge (-NH-CO-NH-SO2-) which has been identified as an important functional structure of SU toxicity. AEF130619 fo rms under both aerobic and anaerobic F0338795; therefore, it will be considered as part of a total toxic resi dues approach in both the terrestrial and aquatic exposure assessments. F0338795 forms under anaerobi c aquatic conditions and is also assumed to form under anaerobic soil conditions. Therefore, F0338795 will be considered as part of a total toxic residue approach for assessing the potent ial risk to via groundwat er irrigation in absence of additional anaerobic soil metabolism data. These transformation products will be considered as toxic as the parent unless additional toxicity data becomes available. An analysis includ ing the safener AEF122006 will be conducted for corn uses only.

While the toxicity of the safener, isoxadifen-ethyl, to some species including aquati c organisms may be greater than the parent, aquatic exposure to th e safener at levels of toxicological concern are not expected based on the current products registered for use on corn. This was determined by calculating a high-end exposure concentration [0.53μg/L (peak)] usin g the GENEEC (v. 2.0 August 2, 2001) 3 

### . Since the high-end estimated exposure concentration is several orde rs of magnitude less than the most sensitive endpoints (freshwater fish
acuteLC 50 

### value of 220 μg/L; freshwater invertebra te acute toxicity estimate = 41 μg/L 4 

### ; fish chronic toxicity estimate = 4 μg/L 8 

### ), risk is not expected. To confirm this analysis, additional data on the mobility of isoxadifenethyl are recommended, as an estimated K
oc 

### value was used in the modeling. Additionally, it is noted that with a log K OW 

### of 5.66 5 

### , this chemical does have the potential to bioaccumulate.

The results of the GENEEC analysis are provided in APPENDIX E



## Measures of Exposure

In order to estimate risks of foramsulfuron exposure to aquatic and terrestrial organisms, all exposure modeling and resulting risk conclusions will be made based on maximum application rates, application methods, and any mitigation measures specifically indicated on the label. Th e models that will be used to predict the estimated environmental concentrations (EECs) of foramsulfuron are discussed on OPP’s model website. 6 

### These models

3 Modeling assumptions: 2 applications at 0.038 lb/a; 3 d minimum retreatment interval; ground application; high boom; no spray drift buffer; fine spray; no incorporation; solubility 1.3 mg/L; Koc = 9777 L/kg; and stable to degradation.

4 ECO SAR prediction

5 EPI Suite KOWWIN v. 1.67 estimate

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

### 19 include: PRZM (Pesticide Root Z one Model) and EXAMS (EXposure An alysis Modeling System), PRZMgroundwater (GW), AgDrift, AgDisp, T-REX, TerrPla nt, SIP (Screening Imbib ition Program), and STIR (Screening Tool for Inhalation Risk).

The results of running the SIP and STIR models are presented in APPENDIX B and APPENDIX C . While the SIP model suggests that there are ex pected concerns for both mammals a nd birds, the model does not perform well with chemicals that have a high a queous solubility and have low toxicity to these organisms. This route of exposure is not likely to be significant enough to cause concern. The anal ysis with STIR indicates no presumed risk to birds or mammals through inhalation of foramsulfuron.



## Measure of Effects

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



## Integration of Exposure and Effects

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

Endangered Species Assessments

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

6. PRELIMINARY IDENTIFICATIO N OF DATA GAPS

Fate

Table 14 identifies the environmental fate studies submitted by the registrant, as well as study classifications
and whether or not additional data ar e needed in order to su pport the registra tion review exposure assessments.
Rationale for the additional datarequested is also presented.

### 20 Table 14. Submitted Environmental Fate Data for Chemical Foramsulfuron

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

835.2120 Hydrolysis 45109324 supplemental no

835.2240 Aqueous photolysis 45109325 acceptable no

835.2410 Soil photolysis yes No acceptable study has been submitted.

Foramsulfuron is toxic to plants. Knowledge of the persistence of
foramsulfuron in soil as well as the identification of transformation products will help the Agency determine and estimate exposure of foramsulfuron and other residues of potential toxicological concern to non-target organisms. The results of this study will be used in the environmental fate assessment, and later on, in the ecological risk
characterization.

835.4100 Aerobic soil
metabolism 45109714 acceptable

no Additional information on soil taxonomy would be helpful; however, it is not expected to change the risk assessment approach or outcome. 45109713 acceptable

835.4200 Anaerobic soil
metabolism No data no 1 N o acceptable study has been submitted.

Foramsulfuron is toxic to plants. Since foramsulfuron has the potential to leach through the soil profile knowledge of the persistence of it in soil as well as the identification of transformation products under anaerobic soil conditions will help the Agency determine and estimate exposure of foramsulfuron and other residues of potential toxicological concern to non-target organisms. The results of this study will be used in the environmental fate assessment, and later on, in the ecological risk characterization of the potential exposure of anaerobic transformation product as results of using groundwater for irrigation.

835.4300 Aerobic aquatic
metabolism 45109728 supplemental no Identification of unknown residues and
non-extracted materials would be helpful; however, we do not expect
identification of these residues to alter
the risk assessment conclusions.

835.4400 Anaerobic aquatic
metabolism 45109729 supplemental

no Identification of unknown residues and
non-extracted materials would be helpful; however, we do not expect
identification of these residues to alter
the risk assessment conclusions. 45109730 supplemental

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

835.1230
835.1240 Adsorption/ desorption and leaching 45109723 acceptable

no 1 Mobility data on isoxadifen-ethyl, the
safener included in the corn formulations (Reg. Nos. 264-686 and 264-685) would be useful to confirm the preliminary exposure analysis completed (see pg. 18). Additional analysis of the effect of the estimated Koc value on expected isoxadifen-ethyl [Koc =977 L/kg (10X less than the EPI estimate); Peak EEC 1.9 μg/L] concentrations suggest that exposure at levels of toxicological concern are not
like to occur even if the estimated Koc value was an order of magnitude over estimated by EPI suite. The GENEEC results are provided in APPENDIX E

. 45109725 acceptable 45109724 acceptable 45109726 acceptable

45109721 supplemental

835.1410 Volatility – laboratory No data no Foramsulfuron is not expected to be volatile based on the reported vapor

pressure.

835.6100 Terrestrial field dissipation 45109722 supplemental no No acceptable environmental chemistry
method for foramsulfuron in soil is currently available.

The MRIDs 45109722 and 45109420 report the LOQ for foramsulfuron as 2 ppb while MRID 45109421 reports a LOQ of 0.05 ppb. Due to the high sensitivity of plants to foramsulfuron it is important that the detection limits for foramsulfuron in soil capture the level of concern for the most sensitive species including listed plants. There is also no
record of an ILV for foramsulfuron in soil. An ILV should accompany the environmental chemistry method. Analytical
method in soil 45109420 incomplete

yes 45109421 incomplete

835.6200 Aquatic field dissipation No data no

Analytical
method in water 45109422 incomplete

yes No acceptable environmental chemistry
method for foramsulfuron in water is currently available.

The MRIDs 45109422 and 45109423 report the LOQ for foramsulfuron as 0.1 ppb. Due to the high sensitivity of plants to foramsulfuron it is important
that the detection limits for foramsulfuron in water capture the level of concern for the most sensitive species including listed plants. There is also no
record of an ILV for foramsulfuron in water. An ILV should accompany the environmental chemistry method. 45109423 incomplete

165-4 (850.1730) Fish
bioconcentration No data no Foramsulfuron is not expected to
bioaccumulate based on the calculated

K
ow . 1. Additional data would reduce uncertainty. See comments.

### 22 Effects

Table 15 and Table 16 identify the ecological effects studies, as we ll as study classifications and whether or not
further data are needed in order to support risk assessment. Rationale fo r the additional data requested is presented below the tables.

Table 15. Submitted Aquatic Ecologi cal Effects Data for Foramsulfuron

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

risk
assessment? Comments

850.1010 Freshwater
invertebrate acute toxicity 45109906 Supplemental No --

850.1025
850.1035
850.1045
850.1055 Saltwater
invertebrate acute toxicity 45109929 Acceptable No --

45109928 Supplemental

850.1075 Freshwater fish acute toxicity 45109903 Acceptable No --

45109904 Supplemental

850.1075 Saltwater fish acute toxicity 45109927 Acceptable No --

850.1300 Freshwater
invertebrate life cycle 45109907 Acceptable No --

850.1350 Saltwater
invertebrates life cycle No Due to the lack of any indication of toxicity of foramsulfuron to fish or invertebrates, the value of these additional data to the ecological risk assessment is likely low.

850.1400 Freshwater fish early-life stage 46241301 Acceptable No

850.1400 Saltwater fish early-life stage No --

850.1500 Fish life cycle No --

850.4400 Aquatic plant growth:
Tier II vascular plants 45109913
45109911
45109912 Supplemental Acceptable Acceptable Yes A Tier II Aquatic Plant Growth study on Lemna is needed for a typical end use product
for turf uses. Available Lemna toxicity data suggest that aquatic vascular plants are highly sensitive to foramsulfuron; however, only
TGAI and formulations for corn have been tested (these contain a herbicide safener that may influence the final toxicity estimation).

850.5400 Aquatic Plant
Growth: Tier II algae 45109909 Acceptable No --

45109910 Acceptable

45109930 Acceptable

45109908 Acceptable

### 23 Table 16. Submitted Terrestrial Ecologica l Effects Data for Foramsulfuron

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

850.2100 Avian oral toxicity 45109733 Acceptable No Low toxicity to other avian species and low use rates suggest that risk to passerine species is unlikely to exceed levels of concern. 45109734 Acceptable

850.2200 Avian dietary toxicity 45109735 Acceptable No --

45109736 Acceptable

850.2300 Avian reproduction 45109901 Supplemental No --

45109902 Supplemental

Nonguideline Avian inhalation No --

850.3020 Honey bee acute contact toxicity 45109915 Acceptable No --

Honey bee acute oral toxicity 45109914 Acceptable No --

850.3030 Honey bee residue on foliage No --

850.3040 Field testing for pollinators No --

850.4100 Terrestrial plant toxicity: Tier II seedling

emergence 45483802 Acceptable Yes A Tier II Seedling Emergence study is needed for a typical end use product for turf uses. Available toxicity data suggest that terrestrial plants are highly sensitive to foramsulfuron, however only TGAI, and end-use
formulations for corn that contain a safener have been tested (the safener may underestimate the final toxicity estimation).

850.4150 Terrestrial plant toxicity: Tier II vegetative vigor 45483801
45109931 Acceptable Acceptable Yes A Tier II Vegetative Vigor study is needed for a typical end use produ ct for turf uses. Available toxicity data suggest that terrestrial plants are highly sensitive to foramsulfuron, however only TGAI, and end-use
formulations for corn that contain a safener have been tested (the safener may underestimate the final toxicity estimation).

124-1 Terrestrial Plant Field Testing Yes The November 26, 2002 Notice of Registration for EPA Reg. No. 264-686 identified this study as a requirement. To date, it has not been submitted to the EPA.

124-2 Aquatic Plant Field Testing Yes The November 26, 2002 Notice of Registration for EPA Reg. No. 264-686 identified this study as a requirement. To date, it has not been submitted to the EPA.



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

### 24 2. major degradate toxicity data
3. information regarding effects of fo ramsulfuron on plant reproduction ( e.g. , fruit numbers, seed numbers, volume and weight of s eed, number of flowers)
4. label clarifications including maxi mum number of applications per ye ar, maximum application rate per year, and the minimum applic ation treatment interval

### 25 APPENDIX A

Kinetic Analysis Images

MRID 45109714 combined label lowa silty clay loam

MRID 45109714 combined label north carolina loamy sand

### 26 MRID 45109713 combined label shuttleworth sandy loam

MRID 45109713 combined label orainville clay loam

### 27 MRID 45109713 combined label chantepie clay loam

### 28 APPENDIX B
SIP ANALYSIS

Table 1. Inputs

Parameter Value

Chemical name Foramsulfuron
Solubility (in water at 25 o C; mg/L) 94600

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

Mammalian NOAEL (mg/kg-bw) 15000 Mammalian test species laboratory rat Body weight (g) of "other" mammalian species

Avian LD 50 (mg/kg-bw) 2000 Avian test species northern bobwhite quail Body weight (g) of "other" avian species Mineau scaling factor 1.15

Mallard NOAEC (mg/kg-diet) 4438 Bobwhite quail NOAEC (mg/kg-diet) 1000 NOAEC (mg/kg-diet) for other bird species Body weight (g) of other avian species NOAEC (mg/kg-diet) for 2nd other bird species Body weight (g) of 2nd other avian species

Table 2. Mammalian Results

Parameter Acute Chronic Upper bound exposure (mg/kg-bw) 16271.2000 16271.2000 Adjusted toxicity value (mg/kg-bw) 3845.8028 11537.4085 Ratio of exposure to toxicity 4.2309 1.4103

Conclusion* Exposure through drinking water alone is a potential

concern for mammals Exposure through drinking water alone is a potential

concern for mammals

Table 3. Avian Results

Parameter Acute Chronic Upper bound exposure (mg/kg-bw) 76626.0000 76626.0000 Adjusted toxicity value (mg/kg-bw) 1440.8590 106.2983 Ratio of exposure to acute toxicity 53.1808 720.8580

Conclusion* Exposure through drinking water alone is a potential
concern for birds Exposure through drinking water alone is a potential
concern for birds

*Conclusion is for drinking water exposure alone. This does not combine all routes of exposure. Therefore, when aggregated with other routes ( i.e ., diet, inhalation, dermal), pesticide exposure through drinking water may contribute to a total exposure that has potential for effects to non-target animals.

### 29 APPENDIX C STIR Analysis Results

Welcome to the EFED

Screening Tool for Inhalation Risk

This tool is designed to provide the risk assesso r with a rapid method for determining the potential

significance of the inhalation exposure route to birds and mammals in a risk assessment.

Input

Application and Chemical Information

Enter Chemical Name t

Enter Chemical Use t Is the Application a Spray? (enter y or n) y If Spray What Type (enter ground or air) air Enter Chemical Molecular Weight (g/mole) 452.3 Enter Chemical Vapor Pressure (mmHg) 7.5E-05
Enter Application Rate (lb a.i./acre) 0.076

Toxicity Properties

Bird

Enter Lowest Bird Oral LD 50 (mg/kg bw) 2000 Enter Mineau Scaling Factor 1.15 Enter Tested Bird Weight (kg) 0.178

Mammal

Enter Lowest Rat Oral LD 50 (mg/kg bw) 5000

Enter Lowest Rat Inhalation LC 50 (mg/L) 5.04 Duration of Rat Inhalation Study (hrs) 4 Enter Rat Weight (kg) 0.35

Output

Results Avian (0.020 kg )

Maximum Vapor Concentration in Air at Saturation (mg/m 3 ) 1.83E+00
Maximum 1-hour Vapor Inhalation Dose (mg/kg) 2.30E-01

Adjusted Inhalation LD 50 1.12E+01

Ratio of Vapor Dose to Adjusted Inhalation LD 50 2.04E-02 Exposure not Likely Significant
Maximum Post-treatment Spray Inhalation Dose (mg/kg) 7.30E-03

Ratio of Droplet Inhalation Do se to Adjusted Inhalation LD 50 6.50E-04 Exposure not Likely Significant

Results Mammalian (0.015 kg )

Maximum Vapor Concentration in Air at Saturation (mg/m 3 ) 1.83E+00
Maximum 1-hour Vapor Inhalation Dose (mg/kg) 2.89E-01

Adjusted Inhalation LD 50 3.00E+02

Ratio of Vapor Dose to Adjusted Inhalation LD 50 9.63E-04 Exposure not Likely Significant
Maximum Post-treatment Spray Inhalation Dose (mg/kg) 9.18E-03

Ratio of Droplet Inhalation Do se to Adjusted Inhalation LD 50 3.06E-05 Exposure not Likely Significant

### 30 APPENDIX D
ECOSAR Results for the Safeners Is oxadifen-ethyl and Mefenpyr-diethyl Isoxadifen-ethyl ECOSAR Version 1.10 Results Page SMILES : C2(C(=O)(OCC))=NOC(C2)(c3ccccc3)c1ccccc1
CHEM :
CAS Num:
ChemID1:
MOL FOR: C18 H17 N1 O3
MOL WT : 295.34 Log Kow: 5.660 (EPISuite Kowwin v1.68 Estimate) Log Kow: (User Entered) Log Kow: (PhysProp DB exp value - for comparison only) Melt Pt: (User Entered for Wat Sol estimate) Melt Pt: (deg C, PhysProp DB exp value for Wat Sol estimate) Wat Sol: 0.1917 (mg/L, EPISuite WSKowwin v1.43 Estimate) Wat Sol: (User Entered) Wat Sol: (PhysProp DB exp value)

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

-------------------------------------- Log Kow: 5.660 (EPISuite Kowwin v1.68 Estimate) Wat Sol: 0.1917 (mg/L, EPISuite WSKowwin v1.43 Estimate)

------------------------------------------------ Available Measured Data from ECOSAR Training Set

------------------------------------------------ Measured CAS No Organism Duration End Pt mg/L (ppm) Ecosar Class Reference

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

========================= 163520-33-0 Daphnid 48-hr LC50 NES Aliphatic Amines OPP Pesticide Ecotoxicity DB

ECOSAR v1.1 Class- specific Estimations Aliphatic Amines
Predicted ECOSAR Class Organism Duration End Pt mg/L (ppm)

=========================== ================== ======== ====== ========== Aliphatic Amines : Fish 96-hr LC50 0.223 * Aliphatic Amines : Daphnid 48-hr LC50 0.041 Aliphatic Amines : Green Algae 96-hr EC50 0.014 Aliphatic Amines : Fish ChV 0.004 Aliphatic Amines : Daphnid ChV 0.005 Aliphatic Amines : Green Algae ChV 0.007

=========================== ================== ======== ====== ========== Neutral Organic SAR : Fish 96-hr LC50 0.125 (Baseline Toxicity) : Daphnid 48-hr LC50 0.133 : Green Algae 96-hr EC50 0.126
: Fish ChV 0.018 : Daphnid ChV 0.025 : Green Algae ChV 0.167

Note: * = asterisk designates: Chemical may not be soluble enough to measure this predicted effect. If the effect level exceeds the water solubility by 10X, typically no effects at saturation (NES) are reported.

### 31 APPENDIX E
GENEEC Results for the Safeners Is oxadifen-ethyl and Mefenpyr-diethyl

Isoxadifen-ethyl

RUN No. 2 FOR isoxadifen-ethyl ON any * INPUT VALUES *

-------------------------------------------------------------------- RATE (#/AC) No.APPS & SOIL SOLUBIL APPL TYPE NO-SPRAY INCORP ONE(MULT) INTERVAL Koc (PPM ) (%DRIFT) (FT) (IN)

-------------------------------------------------------------------- .038( .076) 2 3 9777.0 1.3 GRHIFI( 6.6) .0 .0

FIELD AND STANDARD POND HALFLIFE VALUES (DAYS)

-------------------------------------------------------------------- METABOLIC DAYS UNTIL HYDROLYSIS PHOTOLYSIS ME TABOLIC COMBINED (FIELD) RAIN/RUNOFF (POND) (POND-EFF) (POND) (POND)

-------------------------------------------------------------------- .00 2 N/A .00- .00 .00 .00

GENERIC EECs (IN NANOGRAMS/LITER (PPTr)) Version 2.0 Aug 1, 2001

-------------------------------------------------------------------- PEAK MAX 4 DAY MAX 21 DAY MAX 60 DAY MAX 90 DAY
GEEC AVG GEEC AVG GEEC AVG GEEC AVG GEEC

-------------------------------------------------------------------- 525.66 510.66 427.69 299.21 237.89

RUN No. 4 FOR isoxadifen-ethyl ON any * INPUT VALUES *

-------------------------------------------------------------------- RATE (#/AC) No.APPS & SOIL SOLUBIL APPL TYPE NO-SPRAY INCORP ONE(MULT) INTERVAL Koc (PPM ) (%DRIFT) (FT) (IN)

-------------------------------------------------------------------- .038( .076) 2 3 977.0 1.3 GRHIFI( 6.6) .0 .0

FIELD AND STANDARD POND HALFLIFE VALUES (DAYS)

-------------------------------------------------------------------- METABOLIC DAYS UNTIL HYDROLYSIS PHOTOLYSIS ME TABOLIC COMBINED (FIELD) RAIN/RUNOFF (POND) (POND-EFF) (POND) (POND)

-------------------------------------------------------------------- .00 2 N/A .00- .00 .00 .00

GENERIC EECs (IN MICROGRAMS/LITER (PPB)) Version 2.0 Aug 1, 2001

-------------------------------------------------------------------- PEAK MAX 4 DAY MAX 21 DAY MAX 60 DAY MAX 90 DAY
GEEC AVG GEEC AVG GEEC AVG GEEC AVG GEEC

-------------------------------------------------------------------- 1.88 1.87 1.83 1.74 1.67