Re: Registration of Centaur WDG Insect Growth Regulator (EPA Reg. No ) Containing the Active Ingredient Buprofezin. Chemical Code:

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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 December 31, 2009 VIA UPS Ms. Shannon Yanocha Nichino America, Inc New Linden Hill Road, Suite 501 Wilmington, Delaware Dear Ms. Yanocha: Re: Registration of Centaur WDG Insect Growth Regulator (EPA Reg. No ) Containing the Active Ingredient Buprofezin. Chemical Code: The New York State Department of Environmental Conservation (Department) has completed the technical review of your application received on April 28, The product labeling for Centaur WDG adds stone and pome fruit applications to the list of approved uses for this active ingredient in New York State. The additional proposed uses on stone and pome fruits proposed by this Centaur WDG Insect Growth Regulator product labeling represent a new use pattern on a major crop for New York State. The Department has evaluated potential impacts from this additional use and found the modeled results to be within an acceptable range. The Department has registered the above-referenced product for use in New York State. The Department had raised some concerns regarding potential impacts to groundwater resources as detailed in our letter dated September 30, We received a substantive response from Nichino America, Inc., which addressed our concerns. However, products containing buprofezin will continue to be registered as restricted use and prohibited from use in Nassau and Suffolk Counties on Long Island, to be protective of sensitive aquifers in New York State. Buprofezin has previously been approved for use in NYS on cucurbits (including cucumbers, melons, pumpkins, and squash), lettuce, snap beans, and tomatoes, outdoor and greenhouse ornamentals in containers, greenhouse tomatoes, longan, lychee, pulasan, rambutan, Spanish lime, cotton, almonds, berries, leafing and fruiting vegetables. However, a previous MCL application adding peaches and pome fruit was denied in For the current application review, Nichino America, Inc., submitted a comparative toxicology and application rate information for evaluation of the Centaur WDG product with selected alternatives. Centaur WDG Insect Growth Regulator contains 70% of the active ingredient buprofezin (2-tertbutylimino-3-isopropyl-5-phenyl-1,3,5-thiadiazinan-4-one), which acts by inhibiting chitin biosynthesis, suppressing oviposition and reducing egg viability, and is labeled for the control of insect damage to almond, pistachio, stone fruit and pome fruit.

2 Ms. Shannon Yanocha 2. Pursuant to the review time frame specified in ECL ' , a registration decision date of November 13, 2009 was established. This registration decision date was waived in order that the Department could review the information submitted by Nichino America, Inc. on November 10, The Department has conducted the following technical review for impacts to human health, nontarget organisms, and environmental fate, review summaries are provided below: HUMAN HEALTH RISK ASSESSMENT: The New York State Department of Health (NYSDOH) previously reviewed the toxicological properties (acute, chronic, developmental, reproductive, carcinogenicity, etc.) of the active ingredient buprofezin including the use of buprofezin on apples and peaches, in similar products submitted by the registrant. No additional toxicity data on this active ingredient or the formulated end use product were submitted in the current package, and a search of the scientific literature did not find any additional toxicological data on buprofezin. In our most recent reviews of Centaur and its active ingredient buprofezin, we expressed concern that this chemical has some carcinogenic potential. The United States Environmental Protection Agency (USEPA) classified buprofezin as having suggestive evidence of carcinogenicity, but not sufficient to assess human carcinogenic potential based on an increased incidence of liver tumors in female mice resulting from chronic administration of buprofezin in the diet of these laboratory animals. In addition to a dose-dependent significant increase by pair-wise comparison over controls for combined hepatocellular adenomas/carcinomas, there was a significant positive trend for combined adenomas/carcinomas. However, tumors were only seen in one sex of one species, and genotoxic effects were not found in studies on buprofezin. Nevertheless, we stated that we generally have concerns for registering a pesticide product that has carcinogenic potential unless either the need for the product is significant or it replaces products that pose greater risk. In response to our concern, the registrant submitted additional information comparing the use and toxicity of buprofezin to eight alternative active ingredients (abamectin, azinphos-methyl, beta-cyfluthrin, bifenthrin, carbaryl, chlorpyrifos, pyriproxifen, thiamethoxam) currently registered in New York State for control of insect damage to pome and/or stone fruit. On an acute oral toxicity basis, buprofezin is either similar to (pyriproxifen, thiamethoxam) or less toxic (abamectin, azinphos-methyl, bifenthrin, beta-cyfluthrin, carbaryl, chlorpyrifos) than the alternative active ingredients, and is otherwise unremarkable compared to the alternatives in regard to acute toxicity following inhalation and dermal exposures, dermal and eye irritation and dermal sensitization. Buprofezin caused comparable (generally minor) developmental and/or reproductive effects to the alternatives, with the exception of abamectin and pyriproxifen, which caused more serious effects (abortions, deaths and malformations). Of buprofezin and the eight alternative insecticides reviewed by the registrant, only three were classified by the USEPA as having some carcinogenic potential ( likely human carcinogen -carbaryl, possible human carcinogen -bifenthrin, and suggestive evidence of carcinogenicity - buprofezin). Of these three active ingredients with some carcinogenic potential, buprofezin was the only one that was negative in all genotoxicity studies. The registrant also provided a comparison of the acute population adjusted dose (apad) and the chronic population adjusted dose (cpad) for each active ingredient. In this comparison, the apad for buprofezin (2.0 milligrams per kilogram body weight per day) was greater than those for the alternative active ingredients, generally indicating lower concern for buprofezin's effects following acute dietary exposures. The cpad for buprofezin (0.01 milligrams per kilogram body weight per day) was similar to or greater than the alternative active ingredients (except for pyriproxyfen), again generally indicating a lower concern for buprofezin's effects following chronic dietary exposures.

3 Ms. Shannon Yanocha 3. The registrant also submitted information in response to our request for documentation or endorsements from agricultural authorities to indicate a need for the use of the Centaur product on peaches and pome fruit grown in New York State. Letters of support were submitted by Dr. Peter Shearer of Oregon State University (formerly of Rutgers University in New Jersey) and Peter Jentsch of the Cornell University-New York State Agricultural Experiment Station. These tree fruit entomologists endorsed the use of buprofezin on apples and peaches citing the need for alternative active ingredients to control key insect pests on these crops. In studies conducted by the two entomologists, buprofezin was effective in controlling both scale and leafhoppers. It was stated in these letters that both scale and leafhoppers are becoming less sensitive to the pesticides currently being used to control them. They further state that the availability of a buprofezin-based product would aid in resistance management programs for insect control on peaches and apples. The information submitted by the registrant addresses our request to provide information on both the relative toxicity of buprofezin compared to other similar use insecticides, and the apparent need of the Centaur product for use in peach and apple production. In regard to toxicity, buprofezin appears to be no more toxic overall than the other alternatives in the registrant's comparison. Also, the evidence for buprofezin's carcinogenicity is not strong, and two other active ingredients in this comparison have demonstrated greater carcinogenic potential. A comparison of the apads and cpads of the alternative active ingredients also indicates that buprofezin generally is of lower concern. Based on the letters of support submitted with the registrant's response, buprofezin use appears to be needed for control of scale and leafhoppers in peach and apple production in New York State. These pests are reported to cause significant damage to these important crops in the State due to reduced sensitivity to currently registered pesticides. Given the above, we would not object to the registration of Centaur WDG Insect Growth Regulator in New York State provided that DEC concurs with the registrant's assessment that there is significant need for this product. ECOLOGICAL EFFECTS RISK ASSESSMENT: The Department s Bureau of Habitat (BoH) had reviewed buprofezin applications on apples, pears, and peaches in 2006 for Centaur IGR and had no objection to that proposed registration. Previous reviews of buprofezin products found buprofezin to be practically nontoxic to birds and slightly toxic to mammals. As an example, small mammal chronic feeding thresholds would likely be exceeded for a short period of time on grasses within treated orchards following application. However, the labeled use of the product allows one application per year on apples and two applications per year on peaches and pears. This brief exposure to elevated residues is not likely to result in adverse effects to small mammals. Buprofezin is not acutely toxic to aquatic organisms at concentrations below its water solubility limit, but was toxic in chronic studies conducted with both fish and invertebrates. Again, the number of applications allowed per year of the Centaur WDG product would not likely result in adverse effects to aquatic organisms. Buprofezin had little to no effect on aquatic algae or macrophytes at water concentrations equaling that which would result from the application of the seasonal maximum application rate directly to a water body six inches deep. Buprofezin was also found to be relatively nontoxic to honeybees.

4 Ms. Shannon Yanocha 4. ENVIRONMENTAL FATE ASSESSMENT: The following assessment was prepared by our staff geologist to determine impact to groundwater when Centaur WDG Insect Growth Regulator (EPA Reg. No ) is applied to labeled crops in New York State. The product application rate is modeled using LEACHM, after geology common to New York State. Centaur WDG IGR is a water dispersible granule product containing 0.7 lb ai per pound of product. The current maximum application rate for pome fruit is one application at 1.5 lb ai/a/yr. The maximum application rate for stone fruit and pear crops is two applications of 1.5 lb ai/a, or 3 lb ai/a/yr. The inerts do not appear to be solvent carriers. The label bears the text Centaur WDG is not for sale, sale into, distribution, and or use in Nassau and Suffolk Counties of New York State. TECHNICAL REVIEW Solubility: Buprofezin has a solubility of 0.38 mg/l. Hydrolysis: (MRID ) This study was found to be acceptable. Buprofezin was stable in ph 7 and 9 aqueous buffer solutions. The half-life was estimated to be 51 days in a ph 5 buffer solution. In ph 5 solution, the major degradate N-[[(1.1-dimethylethyl)amino]thioxomethyl]-(1-methylethyl)-N -phenylurea (BF-25) was found at 19% at 30 days. Aqueous Photolysis: (MRID ) USEPA indicated that these studies provided useful information, and can be used to fulfill the USEPA requirements. The phenyl ring-labeled buprofezin degraded with a registrantcalculated half-life of 33 days. No major degradates were detected. Soil Photolysis: (MRID ) This study was found to be acceptable. Buprofezin was photolytically stable in sandy clay loam soils up to 30 days. Aerobic Soil Metabolism: (MRID ) This study was found to be acceptable. Phenyl ring-labeled buprofezin degraded with a registrant-calculated half-life of 24.4 days in a sandy loam soil incubated up to 181 days (calculated using a nonlinear regression model). Phenyl ring-labeled buprofezin degraded with a registrant-calculated half-life of 59.0 days in a sandy loam soil incubated up to 364 days (calculated using a nonlinear regression model). Based on reviewer-calculated first and second half-lives, the dissipation appeared to be biphasic. The June 23, 2001 EFED review indicated that the first order half-life ranged from 37 to 101 days. No major degradates were detected. Anaerobic Aquatic Metabolism: (MRID ) This study was found to be acceptable. Phenyl ringlabeled buprofezin was stable in anaerobic flooded loam sediment up to 364 days. No major degradates were detected in either the soil or water phase. Adsorption/Desorption: (MRID ) Buprofezin was shown to be immobile in batch equilibrium studies. Adsorption K oc s were 85.3 for the clay loam soil, for the silty clay loam soil, 68.8, 90.1 and 87.4 for the three sandy loam soils, 69.5 for the loamy sand soil, and 10.5 for the sand soil. Desorption K oc s were for the clay loam soil and for the silty clay loam soil, 64.7, 85.0 and for the three sandy loam soils, 70.7 for the loamy sand soil and 7.7 for sand soil. For the three sandy soils, the average adsorption K oc was 82, and average desorption K oc was 89.

5 Ms. Shannon Yanocha 5. Aged Leaching: (MRID ) This study was found to be supplemental. Buprofezin, aged under aerobic conditions for 30 days, was not mobile in columns of loamy sand soil, and was slightly mobile in columns of sandy loam soil leached with distilled water. Field Dissipation: (MRID ) This study was found to be scientifically valid and upgradable. At an application rate of 1.5 lb ai/a (4 applications of 0.38 lb ai), on bare ground loamy sand (NC) and sandy loam (CA), the parent had half-lives of 38.1 days and 37.5 days. However, the first California half-life was 28 days, and the replicates ranged from days. In both studies, the parent was found in the cm depth. Computer Modeling: Modeling was performed on Riverhead sand, using 3.0 lb ai/a/yr (pears and stone fruit), a Freundlich K des of 89 (the average of the 3 sandy loam soils) and an aerobic half-life of 37 days (the lower aerobic metabolism half-life and the field dissipation half-life). The model projected peaks ranging from approximately 1 to 6.5 ppb. Modeling the longer half-life of 101 days, the model projected peaks ranging from approximately ppb. Changing to the lower application rate of 1.5 lb ai/a/yr (apples), the model projected peaks starting in the second year ranging from approximately 0.2 to 4 ppb. Changing to the longer half-life of 101 days, the model projected peaks ranging from approximately 7 to 35 ppb. Environmental Assessment Summary: Staff reviewed the information submitted by Nichino America, Inc., on November 10, 2009 and determined that the original modeling conducted in 2005 had since been corrupted, hence, the above computer modeling paragraph has been corrected to report the model projected peaks. Further, staff contacted soil scientists in regions of New York State where apple orchards are prevalent and verified information reported by Nichino America, Inc. Soil scientists reported that most of the orchard areas in New York State are indeed located predominantly in gravelly loam and silty loam soils except for those orchards located on Long Island. Rerunning the LEACHM model using parameters for these soil types would essentially show no migration of the active ingredient through soils and no measurable impact to groundwater resources. PRODUCT REGISTRATION SUMMARY: The Department has received letters of support for the registration of this product from research entomologists studying impacts to orchard crops through Cornell University and Oregon State University. Both researchers support the registration of Centaur WDG Insect Growth Regulator on orchard crops as a means of controlling pests by providing another mode of action to a now limited tool box of insecticides for use on apple crops. Registration of Centaur WDG will likely improve IPM for resistance management of pests such as the San Jose scale and improve the quality of orchard crops in New York State. Enclosed for your record is a copy of the stamped accepted labeling and Certificate of Registration for Centaur WDG Insect Growth Regulator (EPA Reg. No ). Buprofezin was initially registered as a new active ingredient in New York State, on May 21, This registration of Applaud 70 WP required the product labeling to state that the product is Not for Sale, Sale into, Distribution and or Use in Nassau and Suffolk Counties of New York. This same labeling requirement is applied to the registration of Centaur WDG Insect Growth Regulator. As noted in the ARESTRICTION@ column on the Certificate, this product is classified as ARestricted Use@ under rules and regulations 6 NYCRR Part (e). As such, this product is restricted in its purchase, sale, sale into, distribution, use and possession in New York State.

6 Ms. Shannon Yanocha 6. 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." Should you require information to obtain a commercial permit, please contact the Pesticide Certification Section, at (518) The Pesticide Reporting Law (PRL) in the Environmental Conservation Law Article 33 Title 12 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 protection. 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 call (518) Please note that a proposal by Nichino America, Inc., or any other registrant, to register a product that contains buprofezin for use on other food crops, or any other labeled uses that are likely to increase the potential for significant impact to humans, nontarget organisms, or the environment, would constitute a major change in labeled (MCL) use pattern. Such an application must be accompanied by a new application fee and meet the requirements listed in Appendix 1.B. of ANew York State Pesticide Product Registration Procedures@ (April 2009). Such information, as well as forms, can be accessed at our website as listed in our letterhead. Please be aware that any unregistered product may not be sold, offered for sale, distributed, or used in New York State. Enclosure If you have any questions on this matter, please contact Paula McBath, at (518) Sincerely, Maureen P. Serafini Maureen P. Serafini Director Bureau of Pesticides Management cc: w/enc. - A. Grey/E. Horn/D. Luttinger - NYS Dept. of Health R. Mungari - NYS Dept. of Ag. & Markets W. Smith - Cornell University, PSUR