January 12, VIA (Company # 100) Ms. Susan Person Syngenta Crop Protection, LLC P.O. Box Greensboro, North Carolina

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1 (518) January 12, 2018 VIA (Company # 100) Ms. Susan Person Syngenta Crop Protection, LLC P.O. Box Greensboro, North Carolina Re: Registration of Axial XL Herbicide (EPA Reg. No ) for Control of Grass Weeds in Wheat and Barley Crops. Contains the New Active Ingredient: Pinoxaden (chemical code: ). Dear Ms. Person: The New York State Department of Environmental Conservation (Department) has completed our review of the application and data package for the above-referenced product received on July 17, Axial XL Herbicide contains the active ingredient pinoxaden which is not registered in New York State and is considered a new active ingredient (NAI) requiring technical review prior to registration and use in New York State. Axial XL Herbicide is labeled for post-emergence control of grass weeds in wheat and barley. One application per crop season is allowed at 16.4 fluid ounces of the product formulation and is equivalent to pounds of pinoxaden per acre (per year). Applications may be made with ground or aerial equipment. The Department has completed review of all submitted documentation and prepared final assessments for impacts to human health, ecotoxicology, and environmental fate. Axial XL Herbicide and the active ingredient pinoxaden have been determined to cause no negative impact to New York State resources based on the labeled use of this product. The full text of these assessments are included in the Appendix. The Department has registered Axial XL Herbicide (EPA Reg. No ) which contains the new active ingredient pinoxaden in New York State for labeled uses without restriction. Please find enclosed for your record, copies of the Certificate of Pesticide Registration and the stamped Accepted for Registration label for Axial XL Herbicide.

2 Ms. Susan Person 2. Please note that a proposal by Syngenta Crop Protection, LLC or any other registrant, to register a product that contains pinoxaden, and whose labeled uses are likely to increase the potential for significant impact on humans, non-target organisms, or the environment, would constitute a major change in labeling. Such an application must be accompanied by a new application fee and meet the requirements listed on our website. This information, as well as forms, can be accessed at: Please contact the Pesticide Product Registration Section at (518) , if you have any questions regarding this letter. Sincerely, /s/ Enclosures Scott Menrath, P.E. Director Bureau of Pest Management

3 Ms. Susan Person 3. APPENDIX HUMAN HEALTH RISK ASSESSMENT: The New York State Department of Health (DOH) reviewed the application and supporting data submitted by Syngenta Crop Protection, LLC to register the pesticide product Axial XL Herbicide (EPA Reg. No ) in New York State. This product contains the new active ingredient pinoxaden (8-(2,6-diethyl-4-methylphenyl)-1,2,4,5- tetrahydro-7-oxo-7h-pyrazolo[1,2-d][1,4,5]oxadiazepin-9-yl 2,2-dimethylpropanoate) and is labeled for control of grass weeds in wheat and barley. Acute Toxicity Neither pinoxaden nor the formulated product Axial XL Herbicide was very toxic in acute oral, dermal or inhalation exposure studies in laboratory animals. The active ingredient was severely irritating to eyes, but not skin, whereas the formulated product was not an eye irritant, but a severe skin irritant (tested on rabbits). Neither pinoxaden nor Axial was a skin sensitizer (tested on guinea pigs). Neurotoxicity Both acute and subchronic oral neurotoxicity studies were conducted on pinoxaden in rats. In the acute study, this chemical did not cause any adverse neurotoxic effects up to a dose level of 2,000 milligrams per kilogram body weight (mg/kg), the highest dose tested. Neurotoxic effects were not observed in the subchronic study, up to a dose level of 500 mg/kg/day. In addition, systemic effects were not reported in either study. Chronic Toxicity Pinoxaden caused some toxicity in chronic feeding studies in laboratory animals. In a chronic gavage study in rats, pinoxaden caused increased mortality, clinical signs, and increased serum urea and creatinine levels in males, as well as decreased body weights and body weight gains, increased water consumption and incidence of urinalysis findings, kidney surface granulation, and microscopic renal lesions in both sexes at 250 mg/kg/day; the no-observed-effect-level (NOEL) was 100 mg/kg/day. Adverse effects were not seen in a chronic study in dogs given pinoxaden via capsule up to 125 mg/kg/day, the highest dose tested. Statistically significant toxic effects were not seen in a chronic feeding/carcinogenicity study in mice with pinoxaden up to dose levels of 181 mg/kg/day in males and 216 mg/kg/day in females. However, animals in the high dose groups (573 mg/kg/day in males and 706 mg/kg/day in females) were terminated at week 40 due to excessive decreases in body weight gain. The U.S. Environmental Protection Agency (U.S. EPA) classified this study as unacceptable due to inadequate dosing, but did not require that the registrant conduct another chronic feeding/carcinogenicity study in mice. The U.S. EPA considered the effects seen in the reproductive and developmental toxicity studies as the most significant endpoints of concern in the pinoxaden toxicity database.

4 Ms. Susan Person 4. Developmental/Reproductive Toxicity Pinoxaden caused some developmental toxicity in rats and rabbits exposed during gestation at dose levels that also caused maternal toxicity. In the rat study, pinoxaden caused delays in ossification in the skull and hind digits at 300 mg/kg/day; the NOEL was 30 mg/kg/day. Maternal toxicity characterized by decreased body weight gains and food consumption was observed at 300 mg/kg/day; the NOEL was 30 mg/kg/day. An increased incidence of complete early litter resorption was observed in rabbits at 100 mg/kg/day; the NOEL was 30 mg/kg/day. In addition, increased mortality and abortions, as well as decreased body weights, body weight gains and food consumption were seen in maternal animals at 100 mg/kg/day; the NOEL was 30 mg/kg/day. In a multi-generation reproduction study in rats, pinoxaden was associated with decreased body weights and body weight gains in the F1 pups, and decreased body weights in the F2 males at 500 mg/kg/day; the NOEL was 250 mg/kg/day. Parental toxicity consisted of increased water consumption, renal tubular atrophy, and chronic nephropathy in both sexes, as well as increased incidence of renal pelvic dilatation in males at 500 mg/kg/day; the NOEL was 250 mg/kg/day. The U.S. EPA Office of Pesticide Programs (OPP) established an acute reference dose (arfd) for females years old of 0.3 mg/kg and a chronic oral reference dose (crfd) for the general public of 0.3 mg/kg/day for pinoxaden. Both RfDs are based on the NOEL of 30 mg/kg/day from the developmental toxicity study in rabbits and an uncertainty factor of 100. The crfd value has not yet been adopted by the U.S. EPA Integrated Risk Information System (IRIS). Carcinogenicity The U.S. EPA determined that the available toxicity data for pinoxaden was inadequate for an assessment of human carcinogenic potential. Although no effects were seen in a chronic toxicity/carcinogenicity study in rats, an acceptable carcinogenicity study with pinoxaden in mice is missing from the toxicity database. The U.S. EPA reported the results of two chronic toxicity/carcinogenicity studies with pinoxaden in mice exposed via gavage or dietary administration. The gavage study was considered inadequate due to errors in the administration of the gavage resulting in increased mortality in the study animals. The dosing in the dietary study was considered inadequate due to a lack of toxicity seen at the highest dose of pinoxaden tested; the highest original dose group was terminated at 40 weeks. In addition, pinoxaden was mostly negative in several genotoxicity studies, except for positive findings in two in vitro mammalian cell assays both with and without activation. The U.S. EPA concluded that the overall findings in the available genotoxicity studies demonstrated that pinoxaden is non-mutagenic. Based on the available toxicity data and the overall weight of evidence of pinoxaden s toxicity (i.e., effects seen in the developmental and chronic toxicity studies), the U.S. EPA s Cancer Assessment Review Committee (CARC) believes that pinoxaden is not likely to pose a cancer risk. Dietary Risk Assessment The U.S. EPA established tolerances for pinoxaden residues in or on a number of crops and commodities (Federal Register 70(143): 43,313 22; July 27, 2005). The acute (apad) and chronic (cpad) population adjusted doses for pinoxaden are 0.3

5 Ms. Susan Person 5. mg/kg/day and have the same basis as the arfd and crfd. The U.S. EPA estimated that acute dietary exposures to females years old would be 1.5 percent of the apad. The chronic dietary exposures (food and drinking water) to this active ingredient were estimated to be 0.9 percent of the cpad for the general U.S. population, 0.5 percent for infants less than 1-year old and 2.1 percent for children 1-2 years old, the highest exposed subgroup. These exposure analyses are based on the assumption that 100 percent of labeled crops are treated and contain tolerance level residues. Actual residues and resulting exposure levels are expected to be less than these assessments estimate. Occupational Risk Assessment The U.S. EPA reported the results of an occupational risk assessment for combined dermal and inhalation exposures to pinoxaden from the labeled use of Axial XL Herbicide on wheat and barley via aerial and groundboom application methods. For determining margins of exposure (MOEs), the U.S. EPA compared estimated short-term (1-30 days)/intermediate-term (1-6 months) combined dermal inhalation exposures to a NOEL of 30 mg/kg/day from the developmental toxicity study in rats. The estimated combined dermal and inhalation MOE for mixers/loaders (supporting aerial and groundboom applications) was 2,700, assuming they wore personal protective equipment (coveralls worn over short sleeved shirt and long pants, chemical resistant footwear plus socks and chemical-resistant gloves) as per label requirements. The MOEs for applicators were 30,000 and 27,000 for aerial and open-cab groundboom sprayer respectively. Short-/intermediate-term MOEs for applicators of pinoxaden using an open-cab groundboom sprayer was 27,000. The U.S. EPA considered MOEs of 100- fold or greater in these scenarios to provide adequate worker protection. Drinking Water/Groundwater Standards There are no chemical-specific federal or New York State drinking water/groundwater standards for pinoxaden. Based on its chemical structure, this chemical falls under the 50 micrograms per liter (µg/l) New York State drinking water standard for unspecified organic contaminants (10 NYCRR Part 5, Public Water Systems). In addition, the U.S. EPA has established acute (for females years old) and chronic (for the general public), non-cancer Human Health Benchmark guideline values (i.e., levels in drinking water at or below which adverse health effects are not anticipated from a single or lifetime exposure) for pinoxaden of 8,000 µg/l and 2,000 µg/l, respectively. The U.S. EPA Benchmark guideline values have been developed for pesticide active ingredients that may be found in surface or groundwater sources of drinking water to enable stakeholders to better determine whether the detection of a pesticide in drinking water or source waters for drinking water may indicate a potential health risk. Summary The available information on pinoxaden and the formulated product Axial XL Herbicide indicates that they are not very acutely toxic in laboratory animal studies. However, the active ingredient was a severe eye irritant and the formulated product was a severe skin irritant. Dietary administration of pinoxaden to laboratory animals in

6 Ms. Susan Person 6. chronic, sub-chronic and developmental toxicity studies consistently caused decreased food consumption, body weight and body weight gains across species (dog, rat, rabbit and mouse). Pinoxaden caused some developmental effects in rats and rabbits at dose levels that also caused maternal toxicity, and the U.S. EPA considered the rabbit to be the most sensitive species. The U.S. EPA determined that the available toxicity data for pinoxaden was inadequate for an assessment of human carcinogenic potential. The estimated dietary risks from exposure to pinoxaden from treated crops and drinking water were within the range considered acceptable by the U.S. EPA. In addition, the expected exposure from the labeled use of the formulated product should not pose significant risks to workers. NYS DOH Recommendation The labeled use of Axial XL Herbicide does not appear to pose unreasonable risks to workers or the general public. Although the toxicity database lacks an acceptable chronic toxicity/carcinogenicity study in mice, based on the preponderance of evidence pinoxaden does not appear to be carcinogenic. Given the above, we do not object to the registration of Axial XL Herbicide in New York State. ENVIRONMENTAL FATE RISK ASSESSMENT: The following is the groundwater environmental fate technical review conducted by staff in the Bureau of Pest Management, for the new active ingredient application for pinoxaden contained in Axial XL Herbicide. The sections that follow will include the information that is found in the various environmental fate studies that are required for this technical review. In each section that follows, the corresponding USEPA study Guideline number, the title of the study, and the EPA MRID No, will be included for reference. 1. Guideline No , Sediment and Soil Adsorption/Desorption Batch Equilibrium for NAI Pinoxaden, MRID The adsorption/desorption study using pinoxaden was performed using the five soils that are listed in the following table. The study was classified as acceptable and due to the ph and percent organic carbon (%OC) values listed, being more similar to Riverhead, NY soil, the loamy sand was chosen for subsequent LEACHP modeling (bold values in the table). Soil Type ph %OC Adsorption Koc Loamy sand, North Dakota Loam, North Dakota Sand, Washington Loam, Canada Silty clay loam, Kansas

7 Ms. Susan Person 7. The transformation product NOA did reach major proportions (>10%) at 10.1% and 35.5% in the respective high dosage adsorption and desorption supernatant solutions, but this was attributed to sample storage prior to analysis. Because there were two major degradates (NOA and NOA ) detected in the forthcoming to-be-discussed aerobic soil degradation study, the adsorption/desorption findings for these two major degradates will be covered here as well. 2. Guideline No , Sediment and Soil Adsorption/Desorption Batch Equilibrium for Major Degradate NOA , MRID The adsorption/desorption study using the major degradate NOA was performed using the same five soils as listed. The study was classified as acceptable and due to the ph and percent organic carbon (%OC) values listed, again being more similar to Riverhead, NY soil, and to be consistent with the adsorption/desorption finding for the parent compound, the loamy sand was chosen for subsequent LEACHP modeling (bold values in the table). Soil Type ph %OC NOA Adsorption Koc Loamy sand, North Dakota Loam, North Dakota Sand, Washington Loam, Canada Silty clay loam, Kansas Guideline No , Sediment and Soil Adsorption/Desorption Batch Equilibrium for Major Degradate NOA , MRID The adsorption/desorption study using the major degradate NOA was performed using the five soils that are listed in the following table. The study was classified as acceptable and due to the ph and percent organic carbon (%OC) values listed, and to be consistent with the adsorption/desorption finding for the parent compound and the degradate NOA , the loamy sand was chosen for subsequent LEACHP modeling (bold values in the table). Soil Type ph %OC NOA Adsorption Koc Loamy sand, North Dakota Loam, North Dakota Sand, Washington Loam, Canada Silty clay loam, Kansas

8 Ms. Susan Person Guideline No , Aqueous Hydrolysis, MRID At 25 C the parent compound pinoxaden did undergo hydrolysis at the various ph values tested indicating that hydrolysis would be a major transformation process in an aqueous environment under normal conditions. The length of the study was 30 days and the following table lists the results of the hydrolysis findings: Major Transformation Product Max Percentage At 30 Days Minor Transformation Product ph Half-Life (Days) r NOA None NOA None NOA None NOA None The major degradate at all ph values was NOA and it did not undergo further hydrolysis. No further hydrolysis products were detected and this study was classified as acceptable and scientifically valid. 5. Guideline No , Aqueous Photolysis, MRID The photolytic half-life of irradiated pinoxaden was 14 days based on the 12-hour light and 12-hour dark cycle at N latitude, as reported in the study. The only major transformation product, which was isolated from the irradiated samples and the dark controls, was NOA The study was classified as acceptable and scientifically valid. 6. Guideline No , Photodegradation in Soil, MRID The soil used in this study was Manning loamy sand with ph 8.0 and 1.28 percent organic carbon and the application rate was at lbs ai per acre, which is slightly larger than the maximum labeled rate of 0.05 pounds ai per acre per season. The soils were irradiated for a 12-hour light/12-hour dark cycle at a peak intensity equivalent to that of Greensboro, North Carolina, N latitude. In the irradiated soil pinoxaden decreased from an average 86.38% of the applied to being nondetectable at day 7. In the dark controls, pinoxaden decreased from an average of 90.15% of the applied to non-detectable at day 3. It is further noted in the DER that the half-life in the irradiated soil was 8.9 hours (r 2 = ) while in the dark controls, it was 3.3 hours (r 2 = ), which indicates that the transformation of pinoxaden on soil is not related to photolysis and, therefore, photo-degradation on soil is not expected to be a major transformation pathway under normal environmental conditions. The study was classified as acceptable and scientifically valid.

9 Ms. Susan Person Guideline No , Aerobic Soil Metabolism of Parent Pinoxaden, MRID , , Three studies were submitted with all using one sandy loam soil from North Dakota. The studies and the properties of the soils are listed in the following table. The amount of pinoxaden that was applied to the soil was lbs/acre, which is slightly higher than the maximum labeled rate per season at pounds per acre. The largest half-life (t½) values that appear in the following table will be used in subsequent LEACHP modeling and these values appear in bolded text within the table. t½ Pinoxa den (Days) Soils Type MRID ph %O C Manning loamy sand, North Dakota Manning loamy sand, North Dakota Manning loamy sand, North Dakota t½ NOA (Days) t½ NOA (Days) Maximum Formations of Major Transformation Products The two major transformation products that were detected in all three of the aforementioned aerobic soil metabolism studies were NOA and NOA The following table lists the relevant maximum percentages formed in each study and the highest respective values listed will be used in the determination of their application rate for LEACHP modeling. These factors are shown in bold type in the table. These three studies were classified as acceptable and scientifically valid. MRID Maximum Percentage Relative Transformation Product to Amount of Applied Parent NAO NAO NAO NAO NAO NAO

10 Ms. Susan Person Guideline No , Anaerobic Aquatic Metabolism, MRID The anaerobic biotransformation of pinoxaden was studied in a natural (US) aquatic sediment system under anaerobic laboratory conditions. The following table lists the properties of this system. The only major transformation product was NOA , which was formed within the water layer and the total system at 84.97% and 94.2%, respectively, of the originally applied parent at 28 days post-treatment. This study was classified as acceptable and scientifically valid. Water Soil Type and Origin Pond water/sand sediment system, North Dakota Water ph 8.2 Water %OC Not Reported Sediment ph Sediment %OC t½ Total System (Hours) < 6 9. Guideline No , Terrestrial Field Dissipation, MRIDs Three sets of terrestrial field dissipation studies on pinoxaden were conducted, each had plots on bare ground and on cropped locations. The application rates were all at 0.07 pounds of active ingredient per acre, which is 140% of the maximum labeled rate of lbs. per acre. It was shown that the parent pinoxaden was not found at any site below the 0 15 cm depth where ph values ranged between 6.7 and 8.2 and the percent organic carbon ranged from 0.41 to 2.9. Pinoxaden was not detected in any plot after 21 days post-treatment and the main route of dissipation was by transformation. The major degradates NOA and NOA were found in every plot tested with the maximum depths for NOA ranged from 0-15 cm to cm and for NOA from 0-15 cm to cm. All studies were qualified as supplemental because the concentrations of pinoxaden in the field samples at the time of analysis may have not accurately represented the concentrations in the field at the time of sampling. Although the samples were kept frozen, the lab s holding times were too long. MRID/Study Acceptability / Supplemental Soil Type and Location Loam clay loam, Near Northwood, North Dakota t½ in Soil (Days) Bare Ground 3 Cropped Plot 4 Pinoxaden Max Depth Detected /Days/pH/%OC 0 15 cm/14/7.3/ cm/14/7.1/2.7 Major Transformation Products NOA NOA Dissipation Routes Transformation

11 Ms. Susan Person / Supplemental / Supplemental Loamy sand, Grant County, Washington Sandy loam, Armstrong County, Texas Bare Ground 1 Cropped Plot 8 Bare Ground 7 Cropped Plot cm/3/6.7/ cm/14/7.1/ cm/21/8.2/ cm/21/7.1/0.64 NOA NOA NOA NOA Transformation Transformation 10. LEACHP Modeling of Pinoxaden and the Major Degradates NAO and NOA Max Application Compound MWt Max Formation Fraction Rate (mg/l) Pinoxaden 1 (0.05 lbs ai/acre/yr) NOA NOA As was noted in the previous relevant sections, the following inputs will be used for the LEACHP modeling. Water Solubility 1 (mg/l) Maximum Seasonal Application Rate (lbs ai/acre/yr) Aerobic Soil Half- Life (Days) Adsorption Koc (ml/g) New Active Pinoxaden NOA NOA Pinoxaden, NOA and NOA were LEACHP modeled using the Riverhead, NY soil series and it is shown in the following LEACHP modeling profiles that their maximum leaching output is as follows: Pinoxaden µg/l (ppb) NOA µg/l and NOA µg/l As a result of the above environmental fate review findings and subsequent LEACHP modeling outputs, this reviewer does not object to this new active ingredient pinoxaden being registered in the State of New York. 1 Finding difinitive water solubilities for the two degradates NOA and NOA was challenging so this reviewer used what appears on the PPDB websites here: and respectively.

12 Ms. Susan Person 12. ECOLOGICAL RISK ASSESSMENT The following Ecological Risk Assessment of the new active ingredient pinoxaden was prepared by Department staff in the Division of Fish & Wildlife Bureau of Habitat. All use, chemical characteristics, toxicity, and environmental fate information contained herein were derived from the application and additional data submitted by Syngenta Crop Protection LLC. I. CHEMICAL BACKGROUND Pinoxaden, 8-(2,6-diethyl-4-methylphenyl)-1,2,4,5-tetrahydro-7-oxo-7Hpyrazolo[1,2-d][1,4,5]oxadiazepin-9-yl 2,2-dimethylpropanoate, is a new phenylpyrazolin herbicidal compound for control of grass weeds. Axial XL herbicide is 5.05% pinoxaden, equaling 0.42 pounds per gallon. Use profile Axial XL is labeled for postemergence control of grass weeds in wheat and barley. One application per crop season is allowed at 16.4 fluid ounces of formulation, equaling pounds active ingredient, per acre. Applications may be made with ground or aerial equipment. For broadleaf weed control, Axial XL can be tank-mixed with numerous other products to achieve the desired result. The label lists 45 broadleaf products suitable as tank mix partners. Axial XL is rainfast within 30 minutes of application. Mode of action Pinoxaden is a systemic Group 1 herbicide. It is rapidly absorbed by weed foliage and transported to growing areas of leaves and stems where it inhibits the acetyl CoA carboxylase enzyme thereby inhibiting fatty acid synthesis. Susceptible grasses stop growing within 48 hours, start yellowing, and are completely controlled within 3 to 5 weeks. Physical/chemical properties Pinoxaden is a relatively soluble compound that has the potential to be moderately mobile post-application. Two major pinoxaden degradates are identified, they are expected to be mobile. Reported parent properties are given in Table 1. Table 1. Pinoxaden physical and chemical properties. Parameter Value Water solubility 200 mg/l Octanol/water partitioning coefficient Log KOW = 3.2 Soil partitioning coefficient Mean KOC = 436 Density 1.16 g/ml Vapor pressure 1.5 x 10-9 mmhg

13 Ms. Susan Person 13. II. TOXICITY Pinoxaden is practically non-toxic to mammals and birds on an acute basis. It can produce toxicity with chronic exposures but only at levels several orders of magnitude higher than those expected in the field. The available aquatic toxicity study results are weak. There were solubility issues with the active ingredient, ai, in a number of them, mostly due to study design/conduct. That said, pinoxaden is slightly toxic, at most, to fresh water and marine/estuarine fish test species. The parent compound is moderately toxic to mysid shrimp. The Daphnia and Oyster study results classify it as highly toxic to them. Parent pinoxaden is practically non-toxic to adult honey bees on an acute basis by both contact and oral routes. Pinoxaden rapidly transforms primarily to the metabolite NOA in the field. Toxicity for the 2 predominant metabolites are given in Table 2. Toxicity values used in exposure modeling are given in appendix 1. Table 2. Metabolite toxicity. Study type Rainbow trout acute Rainbow trout acute Test compound Results (mg/l) Study classification MRID No. NOA LC 50 >105 Acceptable NOA LC 50 >120 LOEC = 31 NOEC =16 Supplementaltotal organic carbon in test solution too high Supplementalsolubility issues Daphnia lifecycle 21-day NOEC = 5.9 LOEC = 11.9 NOA Daphnia acute NOA EC 50 >120 Supplemental Supplemental- Fathead minnow LOEC> 0.96 NOA many issues, low Early life-stage NOEC 0.96 value study Earthworm subchronic, 14- day Quail reproduction, diet Mallard reproduction, diet * ppm diet NOA NOA NOA LC 50 >1g/kg dry soil NOEC = 556 mg/kg LOEC = 318* NOEC = 107 %viable embryos LOEC>1050* NOEC = 1050 no effects Supplemental- OECD guideline Acceptable Acceptable

14 Ms. Susan Person 14. III. EXPOSURE Pinoxaden rapidly transforms primarily via aerobic microbial metabolism, producing 2 major metabolites. The parent compound degrades to NOA which then degrades to NOA Parent hydrolysis and aquatic photolysis half-lives, T1/2s, are 10 and 14 days respectively. Laboratory aerobic soil metabolism studies, 3 were submitted, yielded calculated T1/2s of 2-3 days. The graphically observed 50% dissipation times, DT50, were roughly 5-7 hours in the same studies. Pinoxaden s vapor pressure is low, volatilization will not contribute significantly to its dissipation. Terrestrial Field Dissipation trials yielded calculated parent T1/2s of 1-8 days in 3 U.S. locations and 2-5 days in 3 different Canadian locations. Metabolite NOA generally reached its maximum concentrations, 32-45% of applied parent, within 1 day in U.S. studies, and 14-44% of applied at 1-6 days in the Canadian trials. NOA field T1/2s from all sites were days with a geometric mean of 5.3 days. Total carryover of parent plus metabolites at the U.S. sites was 0%, 0%, and 1.9% at study termination. Carryover at study termination at the Canadian sites for NOA metabolite was 2.5%, 4%, and 6%, parent compound and NOA metabolite were not detected past 24 days. The applied material was not detected below the top 6-inch soil layer in the U.S. studies with the exception of 1 detection of NOA in one replicate in the 6-12inch soil depth. Laboratory aquatic sediment/water test system dissipation trials show rapid parent pinoxaden transformation to NOA Parent water column and total system dissipation T1/2s are reported as < 1 day, and < 6 hours in the aerobic and anaerobic studies respectively. The only major metabolite (those representing 10% or more of applied parent compound) identified is NOA Unlike terrestrial compartments, in aquatic systems metabolite NOA doesn t appear to degrade farther. In aerobic replicates NOA represented 66-87% of the applied parent at the end of the 147- day study. At the 372-day study termination in anaerobic replicates an average of 74% of the applied material remained as NOA Non-target organism exposure in terrestrial compartments will be for both the parent compound and the 2 major metabolites. In aquatic systems it will be primarily be for the metabolite NOA IV. EXPOSURE MODELING Standard BOH screening level modeling was conducted for potential pinoxaden residues following labeled use. Metabolite NOA toxicity data for several species was used in place of parent compound values for several reasons. First, the aquatic toxicity data is weak in a number of respects so data useful for modeling is limited, but more importantly, the NOA metabolite will be the more significant residue post application. On the terrestrial side, the only data submitted for avian reproductive trials

15 Ms. Susan Person 15. was with the NOA metabolite. There is no mention of parent pinoxaden being used in such work in any of the applicant or EPA materials reviewed to date. V. MODELING RESULTS & RISK ASSESSMENT Conservative, screening level, exposure modeling show that Axial XL Herbicide in this use pattern doesn t, with only 2 exceptions described below, result in field concentrations that exceed toxicity thresholds. The only toxicity thresholds exceeded in BOH screening modeling are the NOEC values for Daphnia and the Oyster in the Direct Application to surface water module used to evaluate risk from aerial application. The reported Daphnia and Oyster study results included an EC50 and IC50, respectively, but neither reported a NOEC value. In these cases, the NOEC data entry input fields are left blank and the model automatically divides the LC50, EC50, etc. by 10 and uses the result as the NOEC. While a conservative approach, this does leave some uncertainty around the true NOEC and/or MATC concentrations. VI. SUMMARY As a result of the above ecotoxicity review findings and subsequent modeling outputs, this reviewer does not object to this new active ingredient pinoxaden being registered in the State of New York. Axial XL Herbicide should not pose undue risk to non-target resources when used according to the label. VII. DATA GAPS & UNCERTAINTIES The U.S. EPA issued a Generic Data Call-in for pinoxaden on April 20, Other than the requirement to develop and validate chemistry methods for pinoxaden and its major degradates in water, the listed work is all honey bee studies. The most recent EPA EFED risk assessment for pinoxaden is dated April It includes the bee information reported previously in this review. Since that time more extensive bee testing methods have been under development and, with guideline study protocols being fairly well developed, the testing of previously registered products is being brought up to date. Pinoxaden is one such example. The Data Call-in lists: larval honeybee acute and chronic tests, adult honeybee chronic oral toxicity, residues in pollen and nectar/field residue analysis, semi-field testing for pollinators (tunnel or colony feeding studies), and field testing for pollinators. The studies are being approached in a stepwise, tiered, manner so all of them might not be conducted. The laboratory larval work and adult chronic study, however, likely will be. As an herbicide with specificity to grasses and shown to be nontoxic to adult bees, pinoxaden isn t likely to be very toxic to larval bees. However, BOH requests that results from the pinoxaden Data Call-in be submitted when available as confirmatory information.