Registration of Vista and Spotlight Herbicide (EPA Reg. No ) Which Contain the New Active Ingredient: fluroxypyr (chemical code: )

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1 New York State Department of Environmental Conservation Division of Solid & Hazardous Materials Bureau of Pesticides Management, 11 th Floor 625 Broadway, Albany, New York Phone FAX Website: CERTIFIED MAIL RETURN RECEIPT REQUESTED Mr. Jim Baxter State Regulatory Leader Dow AgroSciences, LLC 9330 Zionsville Road Indianapolis, Indiana Dear Mr. Baxter: May 2, 2006 Re: Registration of Vista and Spotlight Herbicide (EPA Reg. No ) Which Contain the New Active Ingredient: fluroxypyr (chemical code: ) The New York State Department of Environmental Conservation (Department) has completed its technical review of the product application and data package received on February 8, 2005, and additional data packages received on June 1, 2005 and August 15, The information received to date was deemed complete for purposes of technical review per Department letter dated September 29, Vista herbicide contains 26.2% of fluroxypyr MHE (1.5 lb fluroxypyr acid equivalent/gal), which acts as a selective post-emergent control of annual and perennial broadleaf weeds in non-cropland areas such as industrial sites, non-irrigation ditch banks, rightsof-way, and in pine plantations. The maximum application rate is 2.5 pints of product, for a maximum of 0.68 lb ai (0.47 lb acid equivalent) per acre per growing season. The label indicates that on non-cropland and pine plantations, split applications could be made in a single growing season. Spotlight herbicide also contains 26.2% of fluroxypyr MHE (1.5 lb fluroxypyr acid equivalent/gal), for control of annual and perennial broadleaf weeds and woody brush in established turf, including residential lawns, golf courses, sports fields, sod farms and around commercial buildings and other commercial turf areas. The application rate is 2/3 to 2_ pints of product, for a maximum of 0.68 lb ai (0.47 lb acid equivalent) per acre per growing season. The United States Environmental Protection Agency (USEPA) issued a conditional registration for Vista on October 5, The final product labeling for both products complies with the current USEPA label amendment dated June 10, Pursuant to the review time frame specified in ECL , a registration decision date of February 24, 2006 was established. A request for waiver of the decision date from Dow AgroSciences was accepted by the Department on February 22, The Department granted the requested waiver in order for Dow AgroSciences to prepare updated product labeling to register Vista and Spotlight Herbicides in New York State. The Department conducted the following technical reviews with regard to the registration of Vista and Spotlight Herbicides for impacts to human health, nontarget organisms, and the environment. Review summaries are provided below:

2 Mr. Jim Baxter 2. New York State Department of Health Review: VISTA We reviewed the application and supporting data submitted by Dow AgroSciences, LLC to register the pesticide product Vista (EPA Reg. No ) in New York State. Vista contains the new active ingredient fluroxypyr 1-methylheptyl ester (((4-amino-3,5-dichloro-6- fluoro-2-pyridinyl)oxy) acetic acid, 1-methylheptyl ester) and is labeled for selective postemergence control of annual and perennial broadleaf weeds and woody brush in non-cropland areas including industrial sites, nonirrigation ditch banks, and rights-of-way such as electrical power lines, communication lines, pipelines, roadsides and railroads including grazed areas within these sites, and pine plantations. Neither the active ingredient fluroxypyr-1-methylheptyl ester nor the formulated product Vista was very toxic in acute oral or dermal exposure studies in laboratory animals, nor were they dermal sensitizers (tested on guinea pigs) or very irritating to the skin (tested on rabbits). Whereas the formulated product was not very acutely toxic by the inhalation exposure route, the active ingredient was moderately toxic. Fluroxypyr was only mildly irritating to the eyes (tested on rabbits), but the formulated product was moderately irritating. Because the active ingredient fluroxypyr-1-methylheptyl ester rapidly hydrolyzes in water to fluroxypyr (the acid form), toxicological studies conducted on fluroxypyr are relevant for the toxicological evaluation of the ester form of this chemical. Therefore, except where noted, most of the studies that we reviewed (see below) were conducted on the acid form. Fluroxypyr caused some toxicity in chronic feeding studies conducted on rats and mice. In a chronic feeding/oncogenicity study in rats, kidney effects (increase in kidney weight and chronic progressive glomerulonephropathy) were observed at a dose of 500 milligrams per kilogram body weight per day (mg/kg/day); the no-observed-effect level (NOEL) was 100 mg/kg/day. In a chronic feeding/oncogenicity study in mice, an increased incidence of kidney lesions occurred in females and a decrease in body weight and body weight gain was observed in males at 1,000 mg/kg/day; the NOEL was 300 mg/kg/day. No effects were reported in a oneyear dog feeding study at doses up to 150 mg/kg/day (the highest dose tested). The USEPA Office of Pesticide Programs calculated an oral reference dose (RfD) for fluroxypyr of one mg/kg/day based on the NOEL of 100 mg/kg/day from the chronic feeding/oncogenicity study in rats and an uncertainty factor of 100. This RfD value has not yet been adopted by the USEPA Integrated Risk Information System (IRIS). No developmental toxicity occurred in pregnant rats administered fluroxypyr 1- methylheptyl ester or in pregnant rabbits given fluroxypyr at the respective highest doses tested, which were 600 and 250 mg/kg/day (the 400 mg/kg/day group in the rabbit study was terminated early due to maternal deaths, and thus developmental effects were not evaluated). Maternal toxicity, characterized by an increase in maternal deaths in both pregnant rats and rabbits occurred at doses of 600 and 400 mg/kg/day, respectively; the respective NOELs were 300 and 250 mg/kg/day. In a rat multigeneration reproduction study, feeding fluroxypyr caused a decrease in rat pup bodyweight and body weight gain at a dose of 1,000 mg/kg/day; the NOEL was 500 mg/kg/day. Parental toxicity, characterized by kidney effects in males and females occurred at doses of 500 and 1,000 mg/kg/day, respectively; the respective NOELs were 100 and 500 mg/kg/day. No effects on reproduction were noted. Fluroxypyr did not cause oncogenic effects in either rat or mouse chronic feeding studies. In addition, genotoxicity studies on fluroxypyr 1-methylheptyl ester gave negative results. Based on the lack of evidence for carcinogenicity in rats and mice, the USEPA classified fluroxypyr as not likely to be a human carcinogen.

3 Mr. Jim Baxter 3. The USEPA reported the results of a risk assessment for dermal and inhalation exposure of workers (mixer/loader/applicator) to fluroxypyr from ground boom and rights-of-way treatments. For workers, wearing long-sleeved shirt, long pants and gloves (required by the Vista label), the estimated margin of exposure (MOE) for combined dermal and inhalation exposure, based in part on an application rate of 0.05 pounds active ingredient per acre, was 7,500 or greater. Since the actual application rate for fluroxypyr in the Vista product is about ten times greater, the adjusted MOE would then be about 750 or greater. The NOEL used in estimating the MOEs was 100 mg/kg/day, apparently for kidney effects from the multigeneration reproduction and chronic toxicity studies in rats. Generally, the USEPA considers MOEs of 100- fold or greater to provide adequate worker protection. There are no chemical-specific federal or New York State drinking water/groundwater standards for fluroxypyr. Based on its chemical structure, this compound falls under the 50 microgram per liter New York State drinking water standard for unspecified organic contaminants (10 NYCRR Part 5, Public Water Systems). The available information on fluroxypyr and Vista indicates that the labeled uses of the formulated product should not pose significant risks to workers, particularly if they use personal protective equipment required by the label including protective eyewear. The product label also includes the precautionary statement: Causes Substantial But Temporary Eye Injury. Given the above, we do not object to the registration of Vista on the basis of direct human risks. SPOTLIGHT We reviewed the application and supporting data submitted by Dow AgroSciences, LLC to register the pesticide product Spotlight (EPA Reg. No ) in New York State. Spotlight contains the new active ingredient fluroxypyr 1-methylheptyl ester (((4-amino-3,5- dichloro-6-fluoro-2-pyridinyl)oxy) acetic acid, 1-methylheptyl ester) and is labeled for postemergence control of annual and perennial broadleaf weeds and woody brush in established turf, including residential lawns, golf courses, sports fields, sod farms and around commercial buildings and other commercial turf areas. Concurrent with this review of Spotlight, we reviewed Vista, which is identical in formulation to the Spotlight product. In that review, we indicated that Vista and its active ingredient fluroxypyr-1-methylheptyl ester were not very acutely toxic to laboratory animals by the oral or dermal routes of exposure, nor were they dermal sensitizers or very irritating to the skin. Whereas the active ingredient was only mildly irritating to the eyes, the formulated product was moderately irritating. Fluroxypyr was not very acutely toxic by the inhalation exposure route, but the active ingredient was moderately toxic. Fluroxypyr-1-methylheptyl ester or the acid equivalent fluroxypyr did not demonstrate genotoxicity, developmental or reproductive toxicity. The USEPA classified fluroxypyr as not likely to be a human carcinogen. This chemical, however, demonstrated some chronic toxicity characterized primarily by adverse kidney effects, which was also noted in a rat multigeneration reproduction study (parental toxicity). The USEPA Office of Pesticide Programs derived an oral reference dose (RfD) for fluroxypyr of 1 mg/kg/day based on the no-observed-effect level (NOEL) of 100 mg/kg/day in a chronic feeding/oncogenicity study in rats and an uncertainty factor of 100. Occupational exposure to the labeled use of fluroxypyr in the Spotlight product should not pose a significant health risk since the application rate and method of fluroxypyr is about the same as when using the Vista product. The margins of exposure (MOEs) in this case were estimated to be about 750 or greater. In regard to post-application exposures from fluroxypyrtreated residential lawns, MOEs of about 5,800 or greater for adults and about 3,100 or greater

4 Mr. Jim Baxter 4. for children can be calculated. For golfers exposed to fluroxypyr residues from courses treated with the Spotlight product, the estimated MOE was about 84,000 or greater. Generally, the USEPA considers MOEs of 100-fold or greater to provide adequate protection. There are no chemical-specific federal or New York State drinking water/groundwater standards for fluroxypyr. Based on its chemical structure, this compound falls under the 50 microgram per liter New York State drinking water standard for unspecified organic contaminants (10 NYCRR Part 5, Public Water Systems). The available information on fluroxypyr and Spotlight indicates that the labeled uses of the product should not pose significant risks to workers or the general public. To mitigate risks to applicators, the product label requires the use of personal protective equipment including protective eyewear. The product label also includes the precautionary statement: Causes Substantial But Temporary Eye Injury. Given the above, we do not object to the registration of Spotlight on the basis of direct human risks. New York State Ecological Effects Risk Assessment: The Department s Bureau of Habitat (BoH) has no objection to the registration of Vista or Spotlight Herbicide. BoH conducted a screening level assessment and completeness review of the application package. New York State Groundwater Review: Active ingredients: Fluroxypyr MHE: ((4-amino-3,5-dichloro-6-fluoro-2-pyridinyl)oxyl) acetic acid, 1-methylheptyl ester Fluroxypyr: 4-amino-3,5-dichloro-6-fluoro-2-pyridyloxyacetic acid (acid equivalent-active portion) Metabolites: DCP: (pyridinol metabolite) 4-amino-3,5-dichloro-6-fluoro-2-pyridinol MP: (methoxypyridine metabolite) 4-amino-3,5-dichloro-6-fluoro-2- methoxypyridine Technical Review: (The studies were done on the fluroxypyr MHE unless otherwise stated.) Hydrolysis: A DER was submitted for a voluntary supplemental study of the formation of fluroxypyr from fluroxypyr MHE by soil catalysis that is more representative of natural waters (1:100 soil:water). The half-life was two to 5.5 hours. These half-lives were found to be 2,000 to 5,000 times shorter than the 454 day hydrolysis half-life at ph 7 in dilute, buffered sterile solution. The identity of the soil catalyst was unknown. Solubility: The solubility of fluroxypyr is 0.9 ppm. Hydrolysis: According to the EFED Memorandum for the Section 3 Registration of Fluroxypyr Acid and Fluroxypyr MHE (undated), fluroxypyr MHE is stable at ph 5 and 7. Aqueous Photolysis: According to the EFED Memorandum for the Section 3 Registration of Fluroxypyr Acid and Fluroxypyr MHE (undated), fluroxypyr MHE and fluroxypyr do not degrade by photolysis in aqueous environments.

5 Mr. Jim Baxter 5. Soil Photolysis: (MRID ) - This study meets Subdivision N Guidelines. Radiolabeled [ C]fluroxypyr MHE degraded with a registrant calculated extrapolated half-life of days on a clay loam soil. No major degradates were found. Aerobic Soil Metabolism: (MRID ) - According to the August 10, 1993 EF&GW review, the aerobic metabolism study for the parent is acceptable, and the half-lives were 12 days in a silt loam, 23 days in a sandy loam, 12 days in a loam, and seven days in a silty clay soil as an initial rate of degradation. The rate of metabolism slows as fluroxypyr ages in soil, but the memorandum did not provide secondary half-lives. Degradation yields fluroxypyr, DCP at 18.7% and MP at 38.2%. Anaerobic Aquatic Metabolism: (MRID ) - This study meets Subdivision N Guidelines. The registrant calculated half-life of fluroxypyr MHE was 5.1 days in aerobic flooded silt loam. According to the EFED Memorandum for the Section 3 Registration of Fluroxypyr Acid and Fluroxypyr MHE (undated), both fluroxypyr MHE and fluroxypyr are rapidly transformed to DCP and MP. Aerobic Aquatic Metabolism: (MRID ) - This study meets Subdivision N Guidelines. The registrant calculated half-life of fluroxypyr MHE was 5.1 days in aerobic flooded silt loam. It degraded to fluroxypyr (acid equivalent) at 30.9%. Adsorption/Desorption: (MRID ) - According to the 1992 DER, the portion of the study for the fluoroxypyr MHE and fluroxypyr is acceptable. Adsorption Kocs of fluroxypyr acid were 78 in silt loam (ph 5.9, % OC 2.23), 51 in sandy loam (ph 7.5, % OC 0.22), 62 in loam (ph 6.8, % OC 3.08) and 81 in silty clay (ph 7.0, % OC 1.26). Adsorption Kocs of fluroxypyr MHE were 260 in silt loam (ph 5.9, % OC 2.23), 95 in sandy loam (ph 7.5, % OC 0.22), 190 in loam (ph 6.8, % OC 3.08) and 210 in silty clay (ph 7.0, % OC 1.26). Adsorption/Desorption for DCP and MP: (MRID ) - According to the DER dated March 30, 1998, the soil mobility data requirement is not satisfied. Dow AgroSciences subsequently responded, and it appears that the USEPA was satisfied; however, an from the USEPA indicates that an updated DER was not generated. Adsorption Kocs for MP were 464 in loamy sand, 312 in clay loam, 274 in sandy clay loam and 235 in silty clay loam. Freundlich Kads values for DCP were 4.2 for sandy loam, 28.9 for silt loam, 11.9 for sand soil and 43.7 for clay soil. Kocs were not reported. Terrestrial Field Dissipation: This study did not meet Subdivision N Guidelines, but was scientifically valid and provided information on the dissipation of fluroxypyr MHE and fluroxypyr. Total fluroxypyr residues dissipated in silty clay loam, sandy clay loam and loamy sand with registrant calculated half-lives of 24.8, 36.3 and 13.2 days in plots vegetated with spring wheat. The methoxypyridine metabolite was found at 25 to 50 ppb at all three locations. Neither fluroxypyr MHE or its metabolites were found below six inches except for methoxypyridine in the loamy sand at <10 ppb in six- to 12-inch and 12- to 18-inch soils depths. MRID In an acceptable study for fluroxypyr acid, the half-life in a silty clay loam (ph 5.6, % OM 2.08) was 28 days with DCP and MP detected. The terrestrial field dissipation half-life for DCP was ten days, and for MP was seven days. Modeling: Staff modeled fluroxypyr on Riverhead soil using a Koc of 51, a half-life of 23 days and the maximum application rate of 0.47 lb ai/a/yr (acid equivalent the active portion of the chemical). The model projected several peaks, all less than 1.4 ppb. Modeling the degradate DCP on Riverhead soil using a Koc of 4.2, a half-life of ten days and 18.7% of the maximum application rate, or lb ai/a/yr, the model projected two peaks, one at 11 ppb, one at 6.5 ppb. Modeling the degradate MP on Riverhead soil using a Koc of 464, a half-life of seven days and

6 Mr. Jim Baxter % of the maximum application rate, or 0.18 lb ai/a/yr, the model projected several peaks at less than 1.4 X 10-8 ppb. Changing the application rate to one application of 1 1/3 pints, or 0.29 lb ai/a/yr ae, staff modeled fluroxypyr on Riverhead soil using a Koc of 51, a half-life of 23 days. The model projected several peaks, all less than 0.9 ppb. Modeling the degradate DCP on Riverhead soil using a Koc of 4.2, a half-life of ten days and 18.7% of the application rate, or lb ai/a/yr, the model projected several peaks, two peaks at less than 6.5 ppb. Modeling the degradate MP on Riverhead soil using a Koc of 464, a half-life of seven days and 38.2% of the maximum application rate, or 0.11 lb ai/a/yr, the model projected two peaks at less than 1 X 10-8 ppb. Summary: The Department has concerns regarding these products given the very low Kocs. Modeling bare ground applications projected that the parent would leach at about 1.4 ppb nearly every year if used yearly and the degradate DCP would leach at levels up to 11 ppb when used as labeled. Modeling half of the labeled application rate, the model projected the parent would leach at about 0.9 ppb, and the degradate at about 6.5 ppb. The Department also has concerns regarding the solvent carrier listed as an inert, and the potential for it to leach into groundwater. Given the low Kocs, the solvent carrier in the inerts, and the modeling results, it is the Department s concern that these products will leach into groundwater at unacceptable levels in sandy areas of New York State. To mitigate the Department s groundwater contamination concerns, Dow AgroSciences has agreed to add the following label statements to product labeling: A New York State specific label statement Not for Sale, Distribution or Use in Nassau & Suffolk Counties, New York must be prominently displayed on the label front panel of both the Vista and Spotlight herbicide labels. The Department will register Vista and Spotlight herbicide in restricted use status to ensure proper application by trained professional applicators and to track use of the active ingredient in New York State. These label statements will protect groundwater in sensitive areas of New York State. Dow Agrosciences will sticker existing inventory of Spotlight product to notify potential purchasers of the Not for Sale, Distribution or Use in Nassau & Suffolk Counties, New York use limitation. The sticker will be placed on the handle of product containers and on the side of the box(contains two containers). New labeling will be prepared for next season s marketing of the Vista product, which contains the label statement Not for Sale, Distribution or Use in Nassau & Suffolk Counties, New York. Enclosed for your record, are copies of the stamped accepted labeling and the Certificate of Registration for Vista and Spotlight herbicides (EPA Reg. No ). Please note that a proposal by Dow AgroSciences or any other registrant, to register a product that contains fluroxypyr, and whose labeled uses are likely to increase the potential for significant impact to humans, nontarget organisms, or the environment, would constitute a major change in labeled use (MCL) pattern. Such an application must be accompanied by a new application fee and meet the requirements listed in Appendix 1.B. of New York State Pesticide Product Registration Procedures (September 2005). Such information as well as forms can be accessed at our website as listed in our letterhead. Please note that the Vista and Spotlight herbicide products, as noted on the restriction column on the Certificate, are to be classified as restricted use under rules and regulations 6

7 Mr. Jim Baxter 7. NYCRR (e). As such, this product is restricted in its purchase, distribution, sale, use and possession in New York State. According to New York State Department of Environmental Conservation Regulations 6 NYCRR 326.3(a): It shall be unlawful for any person to distribute, sell, offer for sale, purchase for the purpose of resale, or possess for the purpose of resale, any restricted pesticide unless said person shall have applied for, and been issued a commercial permit. The Pesticide Reporting Law (PRL) requires all certified commercial pesticide applicators to report information annually to the Department regarding each pesticide application they make. Commercial pesticide retailers are required to report all sales of restricted pesticide products and sales of general use pesticide products to private applicators for use in agricultural crop production. If no sales are made within New York State, a report still must be filed with the Department indicating this is the case. If you need information relating to the Pesticide Reporting Law, or annual report forms, please visit the Department s website at or contact the Pesticide Reporting & Certification Section, at (518) Should you require information to obtain a commercial permit, please also contact the Pesticide Reporting & Certification Section, at (518) Please be aware that any unregistered product may not be sold, offered for sale, distributed, or used in New York State. Please contact our Pesticide Product Registration Section, at (518) , if you have any questions. Enclosure Sincerely, Maureen P Serafini Maureen P. Serafini Director Bureau of Pesticides Management cc: w/enc. - N. Kim/D. Luttinger - NYS Dept. of Health R. Zimmerman/R. Mungari - NYS Dept. of Ag. & Markets W. Smith - Cornell University, PSUR