May 20, Registration of One New Pesticide Product, Magus Miticide (EPA Reg. No ), Which Contains the New Active Ingredient Fenazaquin

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1 New York State Department of Environmental Conservation Division of Materials Management Bureau of Pest Management, 9 th Floor Product Registration and Pest Management Alternatives Section 625 Broadway, Albany, New York Phone: (518) Fax: (518) Website: Joe Martens Commissioner May 20, 2011 Ms. Kyla Smith Registration Specialist Gowan Company P.O. Box 5569 Yuma, Arizona Dear Ms. Smith: Re: Registration of One New Pesticide Product, Magus Miticide (EPA Reg. No ), Which Contains the New Active Ingredient Fenazaquin The New York State Department of Environmental Conservation (Department) has reviewed your application, received July 7, 2010, and additional information, received July 23, 2010, October 22, 2010 and May 3, 2011, to register one new pesticide product, Magus Miticide (EPA Reg. No ), in New York State. The product contains the active ingredient fenazaquin (chemical code ) which is considered a new active ingredient in New York State. Fenazaquin belongs to the quinazoline class of chemicals and is a pesticide intended to control mites and whiteflies. Magus Miticide is a METI (mitochondrial electron transport inhibitor) classified as Group 21. To prevent or delay resistance development, only apply a single application of Magus per crop per season. Magus Miticide is labeled for foliar application to control mites and whiteflies on ornamental plants (greenhouse, shade houses, field grown and outdoor), Christmas Tree plantations, non-bearing tree fruits and nuts (field grown and nursery) and established ornamental landscape plantings (indoor and outdoor, commercial and residential). The maximum application rate is 24 fluid ounces per acre per year (0.30 lbs. ai per acre per year) for outdoor applications and 48 fluid ounces per acre per year (0.60 lbs. ai per acre per year) for indoor applications. The information supplied to date in support of registration of Magus Miticide has been reviewed by the New York State Department of Health (DOH), the Department s Division of Fish, Wildlife and Marine Resources Bureau of Habitat (BOH) and the Department s groundwater staff. The DOH stated that fenazaquin and the formulated product Magus Miticide were moderately acutely toxic by the oral route of exposure, but not very acutely toxic via the dermal and inhalation routes of exposure in laboratory animal studies. Neither the active ingredient nor the formulated product were eye or skin irritants (tested on rabbits), but both were presumed (in lieu of acceptable dermal sensitization studies demonstrating otherwise) to be skin sensitizers (tested on guinea pigs).

2 Ms. Kyla Smith 2. Fenazaquin caused similar toxic effects in rats, dogs and hamsters (the hamster was chosen over the mouse based on studies suggesting greater sensitivity of the hamster to fenazaquin) in chronic feeding studies. Decreases in body weight, body weight gain, food consumption and food efficiency were reported in rats at a dose of 18.3 milligrams per kilogram body weight per day (mg/kg/day) and in dogs at 12 mg/kg/day. The no-observed-effect-levels (NOELs) were 9.2 mg/kg/day and 5 mg/kg/day in rats and dogs, respectively. In a chronic feeding study in hamsters, fenazaquin caused decreased body weight in females and decreased body weight gain in both sexes at 15 mg/kg/day and 35 mg/kg/day in males and females, respectively. The NOELs were 2 mg/kg/day in males and 15 mg/kg/day in females. Fenazaquin did not cause any developmental toxicity and only slight reproductive toxicity in laboratory animal feeding studies. No signs of developmental toxicity were reported at doses of 40 mg/kg/day in rats and 60 mg/kg/day in rabbits; the highest doses tested. Maternal toxicity in the rat study was characterized by decreased body weight gain, food intake and food efficiency (beginning as early as gestation day 6) at 40 mg/kg/day; the NOEL was 10 mg/kg/day. In the rabbit study, no maternal toxicity was observed up to a dose of 60 mg/kg/day. In a twogeneration reproduction toxicity study in rats, fenazaquin caused decreased weight gain in pups during lactation at 25 mg/kg/day; the NOEL was 5 mg/kg/day. Parental toxicity consisted of excessive salivation and decreases in body weight, body weight gain and food intake at 25 mg/kg/day; the NOEL was 5 mg/kg/day. The U.S. Environmental Protection Agency (U.S. EPA), Office of Pesticide Programs (OPP) established an acute reference dose (arfd) for fenazaquin of 0.1 mg/kg/day based on the NOEL of 10 mg/kg/day from the developmental toxicity study in the rat and an uncertainty factor of 100. This study was deemed appropriate for deriving an arfd because the endpoint (decreased body weight gain, food intake, and food efficiency) could occur following one oral dose and observations in the acute oral toxicity study in rats support observations in the rat developmental study. The U.S. EPA OPP also established a chronic reference dose (crfd) for fenazaquin of 0.05 mg/kg/day from the NOEL of 5 mg/kg/day from the two-generation toxicity study in the rat and an uncertainty factor of 100. These RfDs have not yet been adopted by the U.S. EPA s Integrated Risk Information System (IRIS). Fenazaquin did not cause oncogenic effects in rat or hamster chronic feeding studies. This compound was also mostly negative in a number of genotoxicity studies. The U.S. EPA classified fenazaquin as not likely to be carcinogenic to humans based on the absence of significant tumor increases in two adequate rodent carcinogenicity studies. The U.S. EPA conducted an occupational risk assessment for short-term combined dermal and inhalation exposures to fenazaquin associated with groundboom, airblast, highpressure handwand and backpack sprayer applications to ornamentals. Greenhouse use was not specifically addressed in this assessment. Both dermal and inhalation absorption were assumed to be 100%. For determining margins of exposure (MOEs), the U.S. EPA compared estimated short-term combined dermal and inhalation exposures to a NOEL of 10 mg/kg/day from the developmental toxicity study in rats (decreased body weight gains, food consumption and food efficiency). For mixer/loaders supporting groundboom applications and airblast applications, the MOE for combined exposures were 2,400 and 4,800, respectively. For applicators, the MOEs were 4,000 for groundboom applications and 320 for airblast applications. The MOEs for combined dermal and inhalation exposures for mixer/loader/applicators of high-pressure

3 Ms. Kyla Smith 3. handwand and backpack applications were 140 and 3,200, respectively. These estimates assumed workers wore long-sleeved shirt and long pants, shoes plus socks and chemical resistant gloves (except groundboom and airblast applicators in open cabs) and mixer/loader/applicators of high-pressure handwand applications additionally wore coveralls as per label requirements. The U.S. EPA also estimated post-application occupational exposure risks for short- and intermediate-term dermal exposures to fenazaquin from hand pruning and harvesting. Dermal absorption was assumed to be 100%. For determining post-application MOEs, the U.S. EPA compared estimated dermal exposures to the NOEL listed above for short-term exposures and a NOEL of 5 mg/kg/day from a 90-day feeding study in dogs (decreased body weight, body weight gains, food consumption and food efficiency) for intermediate-term exposures. The postapplication, short-term dermal MOEs were 1,300 for hand pruning and 330 for harvesting. The intermediate-term MOEs were 650 and 160 for hand pruning and harvesting, respectively. The U.S. EPA considers MOEs of 100-fold or greater to provide adequate worker protection from fenazaquin. There are no chemical specific federal or New York State drinking water/groundwater standards for fenazaquin. Based on its chemical structure, this chemical 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 fenazaquin and the formulated product Magus Miticide indicates that they are moderately acutely toxic by the oral route of exposure, but not very acutely toxic via dermal and inhalation exposures in laboratory animal studies. While both the active ingredient and the formulated product are considered skin sensitizers, the label contains the statement Prolonged or frequently repeated skin contact may cause allergic reactions in some individuals and requires handlers to wear personal protective equipment that should minimize skin contact. In chronic toxicity feeding studies in laboratory animals, fenazaquin caused the same non-specific effects in all species (decreases in body weight, body weight gain, food intake, and food efficiency). Fenazaquin did not cause significant reproductive/developmental toxicity or carcinogenicity and was mostly negative for genotoxicity. The available information indicates that the occupational risks associated with the labeled use of fenazaquin are within the range that is generally considered acceptable. Generally, the DOH has concerns for potential increased inhalation exposure of workers to formulated products when used in an enclosed setting, such as Magus Miticide use in a greenhouse. However, even though a risk assessment was not conducted for this setting, fenazaquin has a low vapor pressure (1.4 x 10-7 mm Hg at 20 C), the formulated product does not have any volatile solvents of concern, and the label carries a 12-hour post-application restricted entry interval. Given the above, the DOH does not object to the registration of Magus Miticide in New York State. The Department s BOH completed an ecological assessment of the information submitted to date. The BOH stated that fenazaquin is slightly toxic to birds and mammals on an acute basis, however, predicted field residues should not result in chronic toxicity to either. Fenazaquin is very highly toxic to all aquatic organisms for which there is data. Of six mutagenicity/genotoxicity studies submitted only one yielded positive results, but only at severely cytotoxic concentrations.

4 Ms. Kyla Smith 4. Fenazaquin will have low terrestrial mobility and be moderately persistent postapplication. It is degraded by both biotic and abiotic mechanisms. Aquatic hydrolysis is ph dependent and fenazaquin degrades fastest at low ph and slowest at high ph. It also degrades via aquatic photolysis. No microbial metabolism studies were submitted. No metabolite issues were identified in the submitted data package. According to aquatic exposure modeling conducted by our BOH, a simulated runoff event following fenazaquin application at the maximum label rate, using parameters to maximize transport to surface water, indicates potential for toxic impacts to both freshwater and marine non-target organisms. Adjusting foliar intercept and runoff parameters to reflect moderate field rates for both reduces model pond fenazaquin water concentrations to levels that suggest no adverse impacts to resources. Exposure of non-target organisms from fenazaquin used according to the Magus label should not result in adverse impacts. The fenazaquin data package has many weaknesses and data gaps. The March 31, 2010 EPA fenazaquin Notice of Conditional Registration lists six ecological effects data gaps (toxicity tests), two environmental fate data gaps, five EPA HED required toxicity studies, and four chemistry studies that have to be submitted over the next two years. Additionally, the works submitted to satisfy the Terrestrial Field Dissipation data requirements were all either unrated or were classified supplemental. Practically the only useful information they contained was the rate at which the parent compound disappeared from where it was applied. The Magus use pattern and label restrictions make impacts to non-target organisms unlikely, but fenazaquin does have the potential for significant impacts particularly to aquatic resources. The described data gaps and weaknesses will have to be addressed before any additional uses can be adequately evaluated. The following is the review of the Department s groundwater staff: Magus Miticide is labeled to control mites and whiteflies on ornamental plants (greenhouse, shade houses, field grown and outdoor), Christmas tree plantations, non-bearing tree fruits and nuts (field grown and nursery) and established ornamental landscape plantings (indoor and outdoor, commercial and residential). Aerial application and chemigation are prohibited and the product cannot be applied within 100 feet of a water body. Fenazaquin belongs to the quinazoline class of chemicals and is a mitochondrial electron transport inhibitor (METI) classified as Group 21. To delay or prevent resistance development, a single application of Magus per crop season is allowed. According to the March 31, 2010 Notice of Registration, Gowan must submit within two years, among other studies, an aerobic soil metabolism and aerobic aquatic metabolism study. Technical Review: Solubility: At 20 o C, fenazaquin has a solubility of mg/l at phs 5 and 7, and mg/l at ph 9.

5 Ms. Kyla Smith 5. Hydrolysis: (MRID acceptable). Fenazaquin had a half-life of 9.6 days at ph 5, days at ph 7 and days at ph 9. Aqueous Photolysis: (MRID unrated). Fenazaquin had an environmental phototransformation half-life of 54 days. Aerobic Soil Metabolism: (MRID supplemental) In a sandy loam (ph 7.7, % OM 1.5), fenazaquin had an observed half-life of 56 days with CO 2 as the only major transformation product. The study was supplemental because the formation and decline of transformation products was not adequately addressed, and it could not be confirmed that all major transformation products were identified. Adsorption/Desorption Studies: (MRID supplemental) Soil ph % OM Koc adsorption Sand ,333 Sandy loam ,500 Loam ,200 Clay loam ,083 Aged Leaching: (MRID supplemental) Aged leaching studies were performed on three different soils: sand (ph 7.7, % OM 0.5), sandy loam (ph 7.0, % OM 1.7), and a loam (ph 6.5, % OM 1.8). Study author calculated half-lives were 37 days and 33 days for the quinazoline- and phenyl-labeled samples, respectively, Unaged and Aged Leaching: (MRID supplemental) Aged leaching studies were performed on three different soils: sand (ph 5.8, % OM 0.9), loamy sand (ph 5.4, % OM 3.1), and a sandy loam (ph 6.3, % OM 1.5). Based on the results of both the unaged soil column leaching and the aged soil column leaching studies, fenazaquin is not mobile in soil. EPA indicated that it could not be determined if the foreign soils used in the study were comparable to soils found in a typical fenazaquin use area in the United States. Terrestrial Field Dissipation in Lysimeters: (MRID unrated) In two lysimeters in a loam soil in Indiana, the reviewer-calculated half-life of fenazaquin in soil was 37.7 and 33.8 days. Terrestrial Field Dissipation: (MRID unrated) In a German silt loam (ph 5.8, % OM 1.67), the reviewer-calculated half-life was 40.5 days. In a German sandy loam (ph 6.4, % OM 4.52), the registrant-calculated half-life was 6.25 days. The samples were not analyzed for transformation products in either soil. (MRID supplemental) In an Italian loam (parameters not reported), the reviewercalculated half-life was 44.4 days. In an Italian clay loam, the registrant-calculated half-life was 11.0 days. The samples were not analyzed for transformation products in either soil.

6 Ms. Kyla Smith 6. (MRID supplemental) In a German loamy silt, (ph 6.1, % OM 1.32), the reviewercalculated half-life was 20.7 days. In a German silty loam (parameters not reported), the observed half-life was <30 days. In a German silt (parameters not reported), the reviewercalculated half-life was 26.4 days. The samples were not analyzed for transformation products in any of the soils. Computer Modeling: Computer modeling was not run given the extremely large Kocs. The parent is immobile in all soils. No degradates, other than carbon dioxide, exceeded the 10% level which requires further characterization. Therefore, no computer modeling was run on transformation products. Summary: The parent is immobile in all soils, and carbon dioxide was the only degradate formed over the 10% level. It is unlikely that this product would impact groundwater when used as labeled. Based on the above information, groundwater staff does not object to the registration of the product as labeled. The Department concludes that the use of Magus Miticide should not have an adverse effect on the health of applicators or the general public, the fish and wildlife resources, or the ground and surface water of New York State when used as labeled. Therefore, the Department hereby accepts for registration the new pesticide product Magus Miticide (EPA Reg. No ). A copy of the Certificate of Pesticide Registration and New York State stamped ACCEPTED labeling for Magus Miticide are enclosed for your records. Gowan Company is reminded that if New York State registration is requested for Magus Miticide or any other product which contains fenazaquin with an increased application rate, different application method and/or expanded use sites, the product will be considered a Major Change in Labeling and the Department will require an extensive review. If you have any questions, please contact Ms. Jeanine Broughel, Chief of our Product Registration and Pest Management Alternatives Section, at (518) Enclosures Sincerely, Scott Menrath Scott Menrath, P.E. Director Bureau of Pest Management