August 13, VIA UPS (Co. No ) Ms. Melinda Bowman Valent USA Corporation 1600 Riviera Avenue Walnut Creek, CA Dear Ms.

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1 New York State Department of Environmental Conservation Division of Solid and Hazardous Materials Bureau of Pesticides Management, 11 th Floor 625 Broadway, Albany, New York Phone: (518) Fax: (518) Website: Alexander B. Grannis Commissioner August 13, 2010 VIA UPS (Co. No ) Ms. Melinda Bowman Valent USA Corporation 1600 Riviera Avenue Walnut Creek, CA Dear Ms. Bowman: Re: Registration of Velocity SG Herbicide (EPA Reg. No ) Which Contains the New Active Ingredient Bispyribac-Sodium (Chemical Code ) The New York State Department of Environmental Conservation (Department) has reviewed your application and data package received on May 19, 2009 and additional material received September 11, 2009 for the registration of the above referenced product. Velocity SG herbicide is a selective herbicide for postemergent control of various grass weeds in golf course turfgrass and sod farms. The product also suppresses dollar spot, and suppresses the production of seed heads by annual bluegrass. Velocity SG herbicide is a water-soluble granule that contains 17.6% by weight of bispyribac-sodium. It is to be applied using low-pressure ground broadcast application techniques. The maximum single application rate is 6.0 ounces of Velocity SG Herbicide ( pounds of bispyribac-sodium) per acre per application. The maximum monthly use rate is 12.0 ounces of Velocity SG Herbicide (0.132 pounds of bispyribac-sodium) per acre per 28 days. The maximum annual use rate is 24.0 ounces of Velocity SG Herbicide (0.264 pounds of bispyribac-sodium) per acre per year. The subject application package was determined to be complete for purposes of technical review on March 25, The following technical reviews were performed to evaluate the risk of the proposed use of bispyribac-sodium on the human health, wildlife, and groundwater resources of New York State. Human Health Risk Assessment Neither the active ingredient bispyribac-sodium nor the formulated product Velocity SG Herbicide was very acutely toxic to laboratory animals via the oral, dermal or inhalation routes of exposure. Neither the active ingredient nor the formulated product was very irritating to the eyes and skin (tested on rabbits). In addition, neither of them was a skin sensitizer (tested on guinea pigs).

2 Ms. Melinda Bowman 2. Bispyribac-sodium caused some toxicity in chronic feeding studies in laboratory animals. In a chronic feeding/oncogenicity study in rats, bispyribac-sodium caused macroscopic and microscopic changes in the liver and common bile duct, as well as clinical signs in males at a dose of milligrams per kilogram body weight per day (mg/kg/day); the no-observed-effect level (NOEL) was 10.9 mg/kg/day. Decreases in body weight, body weight gain and food efficiency, clinical effeccts and microscopic changes in the liver and common bile duct occurred in females at a dose level of mg/kg/day; the NOEL was mg/kg/day. In a chronic feeding/oncogenicity study in mice, decreased body weight gain and food efficiency in both sexes and increased incidence of microscopic lesions in the liver and gall bladder of males was reported at doses of 353 mg/kg/day (males) and mg/kg/day (females); the respective NOELs were 14.1 and 17.4 mg/kg/day. In a chronic dog feeding study, bispyribac-sodium caused dose-related increases in intrahepatic bile duct hyperplasia in both sexes, and liver granulation in females at 100 mg/kg/day; the NOEL was 10 mg/kg/day. The U.S. Environmental Protection Agency (U.S. EPA) Office of Pesticide Programs calculated an oral reference dose (RfD) for bispyribac-sodium of 0.1 mg/kg/day based on the NOEL of 10 mg/kg/day in the chronic feeding study in dogs and an uncertainty factor of 100. This RfD value has not yet been adopted by the U.S. EPA s Integrated Risk Information System (IRIS). Bispyribac-sodium did not cause any teratogenic or reproductive toxicity in the offspring of pregnant rats and rabbits exposed to this chemical during organogenesis. No developmental effects were noted in offspring of either species at maternal doses up to 1,000 mg/kg/day in rats and 300 mg/kg/day in rabbits. Maternal toxicity was not noted in the rat study. In the rabbit study, maternal toxicity was characterized by lethargy, diarrhea and decreased body weight gain at 300 mg/kg/day (effects were only found in the range-finding study, not in the full study at this dose); the NOEL was 100 mg/kg/day. In a multi-generation reproduction study in rats, bispyribac-sodium did not cause any reproductive effects up to a dose level of 759 mg/kg/day. Parental toxicity was characterized by trace to mild common bile duct hyperplasia at 75.7 mg/kg/day; the NOEL was 1.5 mg/kg/day. Adverse effects on offspring included decreased body weight, body weight gain and liver weight as well as histopathological changes in the liver at a dose of 759 mg/kg/day; the NOEL was 75.7 mg/kg/day. Bispyribac-sodium did not cause oncogenic effects in rat or mouse chronic feeding studies. This compound was also negative in a number of genotoxicity studies. The U.S. EPA classified bispyribac-sodium as not likely to be carcinogenic to humans. The registrant conducted a worker exposure and risk assessment for use of bispyribacsodium on golf course turf and sod farms. Short- term and intermediate-term dermal exposures were compared to a NOEL of 1,000 mg/kg/day (the highest dose tested) from a 21-day dermal study in rats. Short-term inhalation exposures were compared to a NOEL of 100 mg/kg/day from an oral developmental study in rabbits (lethargy, diarrhea and decreased body weight), and intermediate-term inhalation exposures were compared to a NOEL of 7.2 mg/kg/day from an oral subchronic study in rats (liver/biliary effects and decreased body weights). The combined dermal and inhalation margins of exposure (MOEs) for mixer/loader/applicators at golf courses were estimated to be about 90,000 and 294,000 for short-term and intermediate term exposures, respectively. For mixer/loader/applicators at sod farms, MOEs were estimated to be about 45,000 and 147,000 for short-term and intermediate term exposures, respectively. Workers were assumed to wear long-sleeved shirt and long pants, shoes plus socks, chemical-resistant gloves,

3 Ms. Melinda Bowman 3. as required by the Velocity label. Post-application MOEs for golfers ranged from about 74,000 to 118,000, and MOEs for sod farm workers ranged from about 600 to 6,000. The U.S. EPA generally considers MOEs of 100 or greater to provide adequate worker protection. There are no chemical specific federal or New York State drinking water/groundwater standards for bispyribac-sodium. Based on their chemical structure, bispyribac-sodium and its metabolites fall under the 50 microgram per liter general New York State drinking water standard for an unspecified organic contaminant (10 NYCRR Part 5, Public Water Systems). The available information on bispyribac-sodium and Velocity SG Herbicide indicates that neither the active ingredient nor the formulated product was very acutely toxic, irritating or a skin sensitizer in laboratory animal studies. Data from chronic and developmental/reproductive studies showed that bispyribac-sodium has the potential to cause some toxicity in the liver and bile duct of dogs, rats and mice, but was not carcinogenic. The exposure potential of the general public to bispyribac-sodium is limited due to its labeled application sites (sod farms and certain areas of golf courses) and relatively low application rate (up to 30 grams bispyribac-sodium per acre per application). Estimated risks to workers are in the range that is generally considered acceptable and should be mitigated by the personal protective equipment (long-sleeved shirt and long pants, shoes plus socks, chemical-resistant gloves) and a 12-hour restricted entry interval (for sod farm uses) required on the pesticide label. Given the above, The New York State Department of Health does not object to the registration of Velocity SG Herbicide in the State. Environmental Fate Risk Assessment Degradates: Bx [(4,6-dimethoxypyrimidin-2-yl]-6-hydroxybenzoate 2,6-DBA 2,6-dihyrodroxybenzoic acid DesMe hydroxy-6-[(4-hydroxy-6-methoxypyrimidin-2-yl)oxy]benzoic acid DesMe-2023 sodium 2-(4,6-dimethoxypyrimidin-2-yl)oxy-6-(4-hydroxy-6-methoxypyrimidin- 2-yl)benzoate MeBa 4,6-dihydroxy-2-methoxypyrimidine Me 2 Ba 4,6-dimethoxy-2-hydroxypyrimidine Solubility: The solubility is mg/l. Hydrolysis: (MRID ) In an acceptable study, at 25 o C the half-life at ph 5 was days. At phs 7 and 9, hydrolysis did not make a significant contribution to the degradation process. Photolysis: (MRID ) In a scientifically valid study that satisfies Subdivision N guidelines, the photolysis half-life was 137 days in a clay loam soil (ph 5.8, %OM 5.2). Aqueous Photolysis: (MRID ) In a scientifically valid study that satisfies Subdivision N guidelines, it was determined that photolysis in water does not make a significant contribution to the degradation process. No appreciable degradation was detected. Aerobic Aquatic Metabolism: (MRID ) In a scientifically valid study that satisfies

4 Ms. Melinda Bowman 4. Subdivision N guidelines, bispyribac-sodium degraded with a combined-labeled half-life of days in a Louisiana silt loam (ph 7.3, % OM 0.3) and days in an Arkansas sandy loam soil (ph 6.1, % OM 0.8), both flooded with ABC (sic) well water and incubated in darkness at 25 o C for 30 days. Anaerobic Aquatic Metabolism: (MRID ) In a study that EPA found unacceptable, values were not presented. (MRID ) In a scientifically valid study that satisfies Subdivision N guidelines, bispyribac-sodium degraded with a half-life of days in a Louisiana silt loam soil, and days in an Arkansas sandy loam soil flooded with ABC well water and incubated under anaerobic conditions in darkness at 25 o C for 367 days. Aerobic Metabolism: (MRID ) In a scientifically valid study that satisfies Subdivision N guidelines, in a clay loam soil (ph 6.1) for the first 55 days the half-live was 18.9 days. From 55 days on, the half-life was 97.0 days. Major degradates found were Bx-180 at 11.4%, 2,6-DBA at 11.8% and Me 2 Ba at 12.1%. Valent s 2/18/10 study entitled Metabolism of Bispyribac-Sodium (Pyrimidine and Benzene Labels in Aerobic Soil: Valent s Response to NYSDEC (Letter of November 12, 2009). In a sandy loam soil (ph 6.1, %OM 0.8), the half-lives were 14.0 and 14.1 days. In a silt loam soil (ph 7.6, %OM 4.5), they were 16.1 and 20.7 days. Major degradate DesMe-2023 was found at a high of 17%. The estimated linear half-lives of DesMe-2023 are 58 and 61 days, of BX-180 are 237 and 316 days, of Me 2 Ba is 110 days and of MeBA is 133 days. The estimated non-linear regression half-lives (a better fit) of DesMe-2023 are 39 and 40 days, of BX-180 are 39 and 71 days, of Me 2 Ba is 49 days and of MeBA is 82 days. Adsorption/Desorption: (MRID ) In a scientifically valid study that satisfies Subdivision N guidelines: Soil ph %OM K oc Clay loam Silt loam ads 355 des Sandy loam Silt loam Sand Valent s 2/18/10 study entitled Metabolism of Bispyribac-Sodium (Pyrimidine and Benzene Labels in Aerobic Soil: Valent s Response to NYSDEC (Letter of November 12, 2009). Valent estimated K oc s using HPLC estimation methods, and found the following values: DesMe-2023 is 47, BX-180 is 86, Me 2 Ba is 7, and MeBA is 2. The value for the parent was estimated at 178. Terrestrial Field Dissipation: (MRID ) In a supplemental study in an Illinois loam over clay loam, the half-life and degradates could not be determined because residues were not

5 Ms. Melinda Bowman 5. detected in the soil, except for a single detection immediately after the second application. Also, grass and thatch samples were not analyzed and volatilization and runoff were not studied. Transformation product DesMe-180 was found in the cm soil depth above the Limit of Quantitation once. Terrestrial Field Dissipation: (MRID ) In a study that was found to be supplemental, in a Virginia loam over clay loam, the half-life and degradates could not be determined because grass and thatch samples were not analyzed and volatilization and runoff were not studied. Label Comments: This product may contaminate water through drift of spray in wind. Poorly draining soils and soils with shallow water tables are more prone to produce runoff that contains this product. A level, well maintained vegetative buffer strip between areas to which this product is applied and surface water features such as ponds, streams, and springs will reduce the potential for contamination of water from rainfall-runoff. Runoff of this product will be reduced by avoiding applications when rainfall is forecasted to occur within 24 hours. Computer Modeling: Modeling the parent on Riverhead soil, using a K oc of 186, a half-life of 97 days, and an application rate of lb ai/a/yr, the model projects peaks up to 0.8 ppb. Changing the half-life to 20 days, the model projects peaks up to 3 ppt. Modeling degradate DesMe-2023, using a K oc of 47, a half-life of 40 days and 17% of the application rate or lb ai/a/yr, the model projected peaks up to about 0.37 ppb. Summary: Given the low application rate and the modeling results, Engineering Geology staff have no objections to the registration of this product as labeled for use on turf. Ecological Effects Risk Assessment: Exposure Modeling & Risk Assessment: Bispyribac-sodium does not degrade readily by abiotic processes (i.e., hydrolysis, photolysis) in water or soil. It is degraded metabolically in aerobic soil, although degradation appears to be biphasic. For approximately the first 55 days, bispyribac-sodium was degraded via aerobic soil metabolism with a halflife (T 1/2 ) of 18.9 days. Thereafter, it continued to degrade more slowly with a T 1/2 of about 97 days. Given that 55 days represents about 2.9 half-lives, an initial application of bispyribac-sodium would have degraded by nearly 88% before the second, slower degradation phase. The rate of microbial degradation in anaerobic soil was not evaluated. Three terrestrial field dissipation studies on turf were conducted. In two of the studies, bispyribac-sodium failed to penetrate the turf and thatch layers, and the concentrations in and dissipation from these layers was not evaluated. In the one study in which bispyribac-sodium did penetrate the thatch layer, it dissipated from the underlying soil with a T 1/2 of 8.9 days, and there was no detection of either the parent compound or metabolites below 15 cm. Aquatic metabolism studies were conducted by applying bispyribac-sodium to flooded soil/sediment and water environments in the lab. Bispyribac-sodium was degraded with halflives of 46 days (silt loam) and 82 days (sandy loam) under aerobic conditions, and degraded with half-lives of 88 days (silt loam) and 109 days (sandy loam) under anaerobic conditions. Two aquatic dissipation studies were conducted by treating a field with bispyribac-sodium and

6 Ms. Melinda Bowman 6. then flooding it. In the first study bispyribac-sodium dissipated from the flooded Norwood silty clay loam soil with apparent half-lives of between days, and was only detected in the overlying water column sporadically. In the second study bispyribac-sodium dissipated from the flooded Crowley silt loam soil with apparent half lives of between days, and from the overlying water column with an apparent half life of about 7 days. For the first aquatic dissipation study the half life for the whole system was about 9 days, and about 81 days for the second. Overall, bispyribac-sodium has been described as moderately persistent. The mode of action for bispyribac-sodium is to inhibit the enzyme acetolactate synthase (ALS) and the subsequent biosynthesis of essential amino acids, which in turn interferes with cell division and causes cessation of plant growth, leading to chlorosis, necrosis, and death of sensitive plants. The selectivity of bispyribac-sodium is a result of absorption, translocation, and differential metabolism. In sensitive plants, bispyribac-sodium is absorbed through the leaf surface and translocated throughout the plant. In insensitive plants, such as rice, bispyribacsodium is rapidly metabolized to nonherbicidal products. ALS is not found in animals, therefore bispyribac-sodium would not generally be expected to be particularly toxic to animals, and that appears to be the case. Mammalian and avian single dose LD 50 s both exceeded 2,000 mg/kg bw. Mammalian 90 day dietary No Observed Effects Concentrations (NOECS) were 100 ppm for male rates and 1,000 ppm for female rats. Avian dietary studies showed no effects at concentrations in food exceeding 5,000 mg/kg bw, for both bobwhite quail and mallard ducks. In aquatic toxicity tests for bluegill sunfish, rainbow trout, sheepshead minnow, Daphnia magna, mysid shrimp, and oyster larvae, the 96 hour LC 50 s all exceeded 100 mg/l. The honeybee contact LC 50 exceeded 25 µg/bee. A non-guideline toxicity test was conducted with bispyribac-sodium in soil and earthworms. The LC 50 exceeded 1,000 ppm, the highest concentration tested. Non-target aquatic plants that might be exposed to bispyribac-sodium through runoff or drift appear to be sensitive. A toxicity test conducted with the aquatic macrophyte Lemna gibba (duckweed) showed a seven day EC 50 of mg/l for reduced frond density, and a NOEC of mg/l. The 96 hour EC 50 for the green algae Selenastrum capricornutum was 0.28 mg/l for inhibition of cell density and the NOEC was mg/l. Both freshwater and marine diatoms were not so sensitive, with EC 50 s of about 1 mg/l. The AVTOX model showed no acute or chronic impacts to birds. The lowest toxicity data for mammals was the result of a multigenerational reproduction study with rats. The rats were fed doses of 20, 1,000, and 10,000 ppm bispyribac-sodium in food for about nine months, and the impacts were observed to adults, F 1, and F 2 generations. The lowest no observed adverse effects level (NOAEL) was 20 ppm for adults. The lowest observed adverse effects level (LOAEL) for adults, and the NOAEL for offspring was 1,000 ppm. When these toxicity data are used in the MAMTOX model, reproductive NOAELs for bispyribacsodium residues on short grass and long grass, derived from the maximum seasonal application

7 Ms. Melinda Bowman 7. rate of lbs AI/acre, are exceeded. However, the resulting risk quotients for short and long grass are 1.4 and 1.1 respectively, indicating that the NOAELs are just barely exceeded. Even though bispyribac-sodium is moderately persistent, residues will not be present in treated vegetation for nine months, the duration of the rat reproduction study. The next-lowest toxicity threshold was the 100 ppm NOAEL observed for the 90 chronic dietary study with rats. This NOAEL was not exceeded by any residue values. Because of its mobility and persistence, bispyribac-sodium has the potential to be transported off treated sites to adjacent water bodies via runoff resulting from precipitation events. Given the low application rate, it is apparent, even without modeling, that fish and aquatic invertebrates are not at risk from bispyribac-sodium applications. However, modeling was conducted to evaluate the potential risks to non-target algae and aquatic macrophytes. The PONDTOX model was run with the highest possible runoff rate, 5%, and no allowance for foliar interception. Under these conditions, significant impacts to non-target aquatic macrophytes were noted in one foot, three foot, and six foot deep ponds. However, bispyribac-sodium is applied to turf, and turf considerably impedes runoff. When a value of 50% is entered into the foliar intercept field, the impacts to nontarget macrophytes occur only one foot deep ponds. With a foliar intercept value of 75%, no toxicity thresholds are exceeded. Using a more reasonable runoff rate of 3%, moderate impacts are predicted with no foliar intercept, at and 50% foliar intercept, the macrophyte NOEC is marginally exceeded only in one foot deep ponds. When used as labeled, bispyribac-sodium is unlikely to be harmful to mammals or birds. The MAMTOX model showed a very slight risk based on the exceedance of the NOAEL from a chronic, rat multigenerational reproduction study. However, that NOAEL was derived from a nine month dietary exposure, and bispyribac-sodium will not persist that long in or on treated vegetation. Aquatic modeling suggests that non-target aquatic macrophytes might be at risk from bispyribac-sodium. However, when foliar intercept is taken into consideration, then the potential risks are reduced to marginal levels. The effect noted from the Lemna gibba toxicity test was a reduction in frond density as opposed to lethality. Nontarget aquatic macrophytes exposed to bispyribac-sodium might experience a short term impairment of growth, but because of its fairly rapid disappearance from the water column, as observed in the aquatic dissipation study, it seems unlikely that bispyribac-sodium concentrations in water resulting from runoff would persist long enough to cause significant impairment to the growth of exposed plants. Furthermore, the model only showed an exceedance of toxicity thresholds in one foot deep ponds. When applied as labeled, it is unlikely that bispyribac-sodium would be harmful to fish and wildlife, even though it has been described as moderately persistent. Therefore, the Bureau of Habitat does not object to registration of the Velocity SG Herbicide product in New York State.

8 Ms. Melinda Bowman 8. Summary: The Department hereby accepts the registration of Velocity SG Herbicide (EPA Reg. No ) in New York State. Enclosed for your files is a copy of the stamped Accepted for Registration label and the New York State Certificate of Pesticide Registration for Velocity SG Herbicide. Please be reminded that this application was reviewed only for the particular use pattern and use sites presented on the Velocity SG Herbicide label. Any future application containing bispyribacsodium that is likely to increase the potential for significant impact on humans, non-target organisms, or the environment, would constitute a major change in labeled use pattern. Such an application must be accompanied by a new fee and meet the application requirements specified in 6 NYCRR Part Please contact Michael Sears, of my staff, at (518) if you have any questions regarding this letter. Sincerely, Maureen P. Serafini Enclosures Maureen P. Serafini Director Bureau of Pesticides Management ecc: w/enc. - A. Grey/E. Horn - NYS Dept. of Health - D. Luttinger/J. Storm NYS Dept. of Health - W. Smith - Cornell University, PSUR