New York State Department of Environmental Conservation

Transcription

1 New York State Department of Environmental Conservation Division of Solid and Hazardous Materials Bureau of Pesticides Management, 11th Floor 625 Broadway, Albany, New York Phone: (518) FAX: (518) Website: Alexander B. Grannis Commissioner April 29, 2008 CERTIFIED MAIL RETURN RECEIPT REQUESTED Ms. Susan Person Regulatory Assistant Syngenta Crop Protection Inc. P.O. Box Greensboro, NC Dear Ms. Person: Re: Registration of a New Label and Supplemental Label for the Currently Registered Pesticide Product, Tilt (EPA Reg. No ), Which represents a Major Change in Labeling Application for the Active Ingredient Propiconazole (Chemical Code ) The New York State Department of Environmental Conservation (Department) has reviewed your application, received May 22, 2007 and supplemental information received October 10, 2007, October 24, 2007, November 9, 2007, and March 21, 2008 to register the new label and supplemental label for the currently registered pesticide product Tilt (EPA Reg. No ) in New York State. The application package was initially deemed incomplete on July 21, After more information was received on October 10 and 24, 2007, the application package was deemed complete for purposes of technical review on November 20, Pursuant to the review time frame specified in Environmental Conservation Law (ECL) , a registration decision date of April 18, 2008 was established. On April 17, 2008, the registration date was waived to allow time for a health effects assessment on information received March 31, A new agreed registration date of May 9, 2008 was established. Propiconazole is a triazole fungicide (Group 3) currently registered in New York State for turf and ornamental use, agricultural use on various crops, home garden use, and as a wood preservative. The application for Tilt was determined to be a major change in labeling for the active ingredient, propiconazole due to the proposed additional crops, such as berries, carrots, filberts, onions, sorghum, soybeans, and sugar beets. Tilt contains 3.6 lbs of the active ingredient, propiconazole per gallon and is foliarly applied through ground, aerial or chemigation application at a single application rate of not less than 2 fluid oz per acre or more than 10 fluid oz per acre. This is equivalent to lbs AI per acre ( g AI/acre). The maximum seasonal application rate ranges from 6 32 fluid oz per acre, which is equivalent to lbs AI/acre ( g AI/acre).

2 Ms. Susan Person 2 The Department hereby accepts Tilt (EPA Reg. No ) for registration as labeled in New York State. The Department and the New York State Department of Health evaluated the risk of the proposed expanded use of propiconazole on human health and the environment of New York State. The following technical reviews were performed to assess the risk posed by expanded use of propiconazole in New York State. HUMAN HEALTH RISK ASSESSMENT: The New York State Department of Health (NYSDOH) reviewed the technical data submitted by Syngenta Crop Protection, Inc. in support of the registration of Tilt (EPA Reg. No ) in New York State. NYSDOH stated propiconazole nor Tilt was very acutely toxic in laboratory animal studies, both were dermal sensitizers and moderate eye irritants. The Tilt product was also moderately irritating to skin. Propiconazole caused some toxicity in subchronic and chronic animal feeding studies, particularly liver toxicity. In addition, this chemical caused developmental toxicity in rats, but not rabbits, at doses lower than maternally toxic doses. Propiconazole did not cause reproductive effects in a multi-generation study in rats. Propiconazole was negative in a number of genotoxicity studies, but caused a treatment-related increase in the incidence of liver tumors in male mice in a chronic feeding study. Based on this, the U.S. Environmental Protection Agency (U.S. EPA) classified propiconazole as a Group C - "possible human carcinogen." The U.S. EPA Office of Pesticide Programs calculated an oral reference dose (RfD) of 0.1 milligrams per kilogram body weight per day (mg/kg/day) for propiconazole based on a no-observed-effect level (NOEL) of 10 mg/kg/day in a chronic mouse feeding study (non-neoplastic liver effects) and an uncertainty factor of 100. The U.S. EPA did not recommend quantifying cancer potency as they believe that an RfD approach to risk assessment would be protective of human health. A current search of the toxicological literature did not find any significant new information on the toxicity of propiconazole. The U.S. EPA reported the results of an occupational non-cancer risk assessment for short- and intermediate-term combined dermal and inhalation exposures for commercial/agricultural handler scenarios. These handler scenarios included mixer/loaders (aerial, groundboom, airblast, chemigation applications), applicators (aerial, groundboom, airblast applications) and flaggers (aerial applications) for emulsifiable concentrate formulations such as the Tilt product. For determining margins of exposure (MOEs), the U.S. EPA compared estimated short- (1-30 days) and intermediate-term (1-6 months) combined dermal and inhalation exposures to NOELs of 30 mg/kg/day from the acute neurotoxicity study in rats (piloerection, diarrhea, tiptoe gait) and 10 mg/kg/day from the chronic feeding study in mice (liver toxicity), respectively. The U.S. EPA assumed that absorption via inhalation exposure was equivalent to oral absorption, and that dermal penetration was 40 percent. For commercial mixer/loaders, the MOEs for combined dermal and inhalation exposures were estimated to be between 600 and 60,000 for short-term exposures and between 200 and 20,000 for intermediate-term exposures for the new crops. For commercial applicators, the MOEs for combined dermal and inhalation exposures were estimated to be between 4,600 and 56,000 for short-term exposures and between 1,500 and 19,000 for intermediate-term exposures. These estimates assumed that all workers wore long-sleeved shirt and pants, chemical-resistant gloves, protective eyewear and shoes plus socks as per label requirements. MOEs for a variety of post-application activities (irrigating,

3 Ms. Susan Person 3 scouting, hand weeding, etc.) depending on the individual crop, were estimated to be between 430 and 110,000 and between 140 and 37,000 for short- and intermediate-term exposures, respectively. Generally, the U.S. EPA considers MOEs of 100-fold or greater to provide adequate worker protection. The U.S. EPA also reviewed reports from a number of sources on adverse incidents associated with exposure to propiconazole. These sources included the U.S. EPA Incident Data System ( ), national Poison Control Centers ( ), the California Department of Pesticide Regulation ( ), the National Pesticide Information Center ( ), and the National Institute of Occupational Safety and Health's Sentinel Event Notification System for Occupational Risks ( ). The majority of these cases reported skin symptoms such as rash, swelling, itching and irritation, and respiratory effects such as shortness of breath and difficulty breathing. The U.S. EPA established tolerances for propiconazole residues for a large number of crops and animal tissues (Federal Register 71:55,300-55,307, September 26, 2006). The acute population adjusted dose (apad) for propiconazole is 0.3 mg/kg/day and is based on a NOEL of 30 mg/kg/day for developmental effects in the rat developmental toxicity study. The U.S. EPA estimated that acute dietary exposure to propiconazole residues from all food crops for which there are tolerances, and from drinking water, will be 6 percent of the apad for the general U.S. population, 5 percent of the apad for females 13 years and older and 14 percent for infants less than one year old. The chronic population adjusted dose (cpad) for propiconazole is 0.1 mg/kg/day and has the same basis as the RfD. The U.S. EPA estimated that the chronic dietary exposure to propiconazole residues from all crops for which there are tolerances, and from drinking water, would be 3.1 percent of the cpad for the general U.S. population, 6.6 percent for all infants less than one year old and 7.8 percent for children one to two years old. These exposure analyses are based on the conservative assumptions that 100 percent of the crops are treated and that these treated crops contain tolerance level residues. There are no chemical specific federal or New York State drinking water/groundwater standards for propiconazole. Based on its chemical structure, propiconazole falls 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 indicates that neither propiconazole nor the Tilt product were very acutely toxic, but they were dermal sensitizers and moderate eye irritants, and Tilt was a moderate skin irritant. Although these studies and data from human incidents indicate that propiconazole or products formulated with this active ingredient can cause eye and skin irritation as well as sensitization, these effects should be mitigated for pesticide handlers by the label requirement for personal protective equipment (long-sleeved shirt and long pants, chemical-resistant gloves, shoes plus socks, and protective eyewear) and the label precautionary statements which warn of this potential. Data from subchronic, chronic and developmental animal studies indicate that propiconazole has the potential to cause toxicity, but the estimated non-cancer risks to workers and the public from dietary sources are within the range that is generally considered to be acceptable. The U.S. EPA has classified propiconazole as a Group C- "possible human carcinogen" based on liver tumors in male mice. While evidence for the oncogenicity of propiconazole is not strong, the proposed label changes include a considerable number of new crops with a

4 Ms. Susan Person 4 corresponding increase in dietary exposure. Nevertheless, the NYSDOH generally has concerns for or expanding the use of a pesticide product for food crops if it has oncogenic properties unless either the needs for the product are significant or it replaces products that pose greater risk. Consequently, the NYSDOH did not support the registration of the additional crops for Tilt in New York State, but was willing to review any additional information indicating that Tilt poses lesser risks than the alternatives for those same crops. In response to the concerns raised by the NYSDOH, Syngenta Crop Protection, Inc. submitted a basic comparison, received March 21, 2008, of some toxicological properties of propiconazole to those of the alternative fungicidal active ingredients- captan, chlorothalonil, fenbuconazole, mancozeb and tebuconazole. Regarding acute toxicity, propiconazole overall was not more toxic than the alternatives, but it was a sensitizer. With the exception of one other active ingredient (mancozeb), the alternatives were not sensitizers. The acute population adjusted dose (apad) for propiconazole (0.3 mg/kg/day) is the same or higher than the alternative active ingredients (with the exception of mancozeb), generally indicating lower concern for propiconazole's effects following acute dietary exposures. Similarly, the chronic population adjusted dose (cpad) for propiconazole (0.1 mg/kg/day) is about the same as that derived for captan, but considerably higher than those for the other active ingredients, again indicating a lower concern for propiconazole's effects following chronic dietary exposures. The registrant did not provide a discussion of the reproductive or developmental toxicity of the active ingredients, but indicated that an additional uncertainty factor for Food Quality Protection Act considerations was not required for propiconazole or for mancozeb, captan or fenbuconazole. They indicated that a 3-fold uncertainty factor was required for chlorothalonil, and a 10-fold uncertainty factor was required for tebuconazole and the mancozeb metabolite, ETU. The addition of an uncertainty factor for these active ingredients indicates either a greater potential for causing effects on the fetus or greater uncertainty regarding the database. The registrant also provided some cursory information on crop residues. In terms of percent of the apad utilized by existing tolerances, propiconazole residues would be 8 percent, compared to 36, 87, 3, <1 and 53 percent for captan, ETU, fenbuconazole, mancozeb and tebuconazole, respectively. No apad was derived for chlorothalonil according to the registrant. For the cpad, the existing tolerances utilized 8 percent for propiconazole, compared to <2, 99, 58, 7, <1, and 16 percent for captan, chlorothalonil, ETU, fenbuconazole, mancozeb and tebuconazole, respectively. Regarding carcinogenicity, propiconazole and two other active ingredients (fenbuconazole and tebuconazole) are classified by the U.S. EPA as Group C "possible human carcinogens." Propiconazole produced an increase in tumors of male mice only, whereas fenbuconazole produced tumors in both mice and rats and tebuconazole caused tumors in both male and female mice. Chlorothalonil caused tumors in both mice and rats, and is classified as a "likely human carcinogen". Mancozeb and captan are Group B2 "probable human carcinogens" and produced tumors in both mice and rats (at least some of mancozeb's carcinogenicity is attributed to its metabolite, ETU). The registrant also provided a brief discussion of the use of propiconazole on crops. According to the registrant, the current uses of propiconazole in New York State are primarily for diseases in wheat (Tilt product) and peaches (Orbit product). Of the new crops for the Tilt product, the ones which are relevant to New York State include- soybeans, carrots, onions, strawberries, stone fruit and blueberries. For soybeans, the registrant states that very little

5 Ms. Susan Person 5 fungicide use currently occurs on this crop, but that they wanted propiconazole to be available for treatment of soybean rust should that disease appear in New York State. The registrant anticipates that propiconazole use will be minimal on carrots, onions and strawberries, but that these new uses on the Tilt label will replace some captan, chlorothalonil and mancozeb use. Some new use of propiconazole would be expected for blueberries in the state, but no overall increase of propiconazole use is expected on stone fruit as another propiconazole-containing product (Orbit) is already registered for these crops. Based on the registrant's submission, the additional uses of Tilt would not greatly increase the overall application of propiconazole in the New York State. The registrant's comparison of the toxicological properties of propiconazole to those of alternative fungicides indicates that propiconazole has toxicological properties similar to or lesser than the other active ingredients. Consequently, use of the Tilt product for the new crop uses could replace other products that may pose greater risks. Based on the information provided, the NYSDOH does not object to registration of the additional proposed uses on the Tilt label. ENVIRONMENTAL FATE AND GROUNDWATER IMPACTS: The Department s groundwater staff reviewed the information submitted in support of the major change in labeling for Tilt. The following is the groundwater staff s technical review: Syngenta Crop Protection Inc. is applying to use Tilt (EPA Reg. No ) as a broad spectrum fungicide to control many plant diseases. This label is adding use on berries, carrots, cranberries, filberts, onions, sorghum, soybeans, strawberries and sugar beets. The product cannot be used in greenhouses or for tree injection. The inerts consists of more than 50% aromatic petroleum hydrocarbons. Use in NY Old Label New Label Use in NY Old Label New Label Berries 0.84 Mint Carrots 0.45 Onions 0.45 Celery Pecans 0.90 Cereals Sorghum 0.45 Corn Soybeans 0.34 Cranberries 0.67 Stone Fruit 0.56 Filberts 0.90 Strawberries 0.45 Grass/seed Sugar Beets 0.34 Technical Review Solubility: The solubility of propiconazole is 110 ppm. Hydrolysis: (DER) In a study that EPA found scientifically valid, but supplemental (MRID ), propiconazole was found to be stable at phs 5, 7, and 9.

6 Ms. Susan Person 6 Aqueous Photolysis: (DER) In a study that EPA found acceptable (MRID ), propiconazole was stable in a ph 7 buffer solution. Soil Photolysis: (DER) In a study that EPA found acceptable (MRID ), propiconazole was stable on a sandy loam soil. Aerobic Soil Metabolism: According to the revised RED dated June 29, 2006, in a silty loam soil (ph 7.6 % OC 2.7) the half-life was 70 days. Major transformation product CGA was found at 23.6% and CGA was found at 22.2% (MRID ). In a second study on the same soil, the half-life in the ring-labeled studies was 43 and 47 days. Major transformation product CGA was found at 16.9% (MRID ). In a meeting between Syngenta and the Department, they indicated that it was their belief that the CGA was misidentified, as it never showed up in any other studies. In the 2001 Aerobic Metabolism study done on European soils (submitted as additional information by Syngenta), the half-life in a silt-loam soil with a ph of 7.2 and 2.4%OC was 29.1 days. Major degradate CGA was found at 43.2% (no half-life for this degradate could be determined). In an additional study submitted by Syngenta on the degradate CGA , the half-life was less than one day and major degradates were CGA was found at 88.5% (t ½ 23.2 days) which then degrades to CGA at 10.1% (t ½ 2.4 days). Anaerobic Aquatic Metabolism: (DER) In a study that EPA found scientifically valid (MRID ), propiconazole had a half-life of 363 days under biphasic degradation in a clay (ph 6.7, OM 2.1%)/natural water system from a flooded rice field in Mississippi Aerobic Aquatic Metabolism: According to the revised RED dated June 29, 2006 (MRID ), propiconazole had a half-life of greater than 30 days. Adsorption/Desorption: (DER) In a scientifically valid study (MRID ), propiconazole had the following values. Mobility appears to be dependent upon the soil s organic matter content. Soil Type Adsorption K Desorption K % OM ph oc Sand Silt loam Sandy loam Silty clay loam Clay loam oc Terrestrial Field Dissipation: (DER) All three studies were partially acceptable:

7 Ms. Susan Person 7 Study Parent halflife in days Major degradates* Terrestrial field dissipation study MRID & bare ground; sandy loam soil ph 8.7, % OM CGA ppb CGA ppb CGA ppb Terrestrial field dissipation study MRID & turf plot; sandy loam-loam ph 7.5, % OM 2.2 grass 16 thatch 110 soil-not analyzed CGA ppb CGA ppb Terrestrial field dissipation study MRID ; sandy loam soil ph 6.1, % OM CGA ppb 4.5% CGA ppb 4.3% *A major degradate in the terrestrial field dissipation study is a concentration in the soil at 10% of applied or for this chemical, 0.01 ppb. Computer Modeling: Running propiconazole using Riverhead soil, a K oc of 893, a half-life of 70 days and an application rate of 0.9 lb ai/a/yr, the model projected cyclic peaks at about ppb. Running the model using the terrestrial field dissipation half-life of 482 days (a more conservative approach), the model projected increasing concentrations reaching 1.2 ppb after 10 years. Running the model using the terrestrial field dissipation half-life of 462 days and 0.45 lb ai/a/yr (50% application rate) the model projected increasing concentrations reaching 0.6 ppb after 10 years. Staff ran modeling on the degradate CGA using a half-life of 23.2 days, an application rate of 0.79 lb ai/a/year (88.5% of parent) and a Koc of 50 (none was available, so a worse case Koc was chosen). The model projected cyclic peaks of between 0 and 2.5 ppb. Staff ran modeling on the degradate CGA using a half-life of 2.4 days, an application rate of 0.09 lb ai/a/year (10.1% of parent) and a Koc of 50 (none was available, so a worse case Koc was chosen). The model projected one peak at ppb. Staff were unable to run CGA because no data was available. Groundwater Monitoring: Staff checked the PRL database and in 2003, 9132 lbs of ai were used; in 2004, 1913 lbs of ai were used in Suffolk County, NY. Groundwater analysis by the Suffolk County Department of Health Services, indicated the following detections of propiconazole (ppb) Stonebridge Golf Course, Hauppauge, NY, surface water 0.2 Rolling Oaks Golf Course, Rocky Point, NY, surface water St. George s Golf Course, Stony Brook, NY, surface water 0.8 Golf Course Flower Rd, Mastic Beach, NY, well Country Rd, Patchogue, NY, well Terry Lane, Orient Pt, NY, well 0.1 Brecknock Hall Greenpoint, NY, well 2002 ND Note: most of the reported detection limits for propiconazole are 0.2 ppb.

8 Ms. Susan Person 8 Summary: While the modeling for propconazole at the longest half-life and for the degradate, CGA shows a potential for negative impact to groundwater, there are many products containing propiconazole currently registered for use on turf at 6 lb ai/a/yr. It is staff s opinion that registering these new uses for Tilt will not have an additional negative impact on groundwater. Therefore, staff have no objections to the registration of this product as labeled. ECOLOGICAL RISK ASSESSMENT: The Bureau of Habitat (BOH) has reviewed the technical data submitted by Syngenta Crop Protection, Inc. in support of the registration of Tilt (EPA Reg. No ) in New York State. Toxicity: Propiconazole exhibits low toxicity to birds and mammals, however it exhibits an increased toxicity to fish and aquatic organisms. A table summarizing the toxicology data of propiconazole is located below. Test Test Organism Results Mammalian and avian single dose, acute oral Mouse Mallard Duck LD50 = 729 mg/kg BW LD50 = 2510 mg/kg BW Avian dietary exposure Mallard Duck LC50 = 5620 ppm food Mammalian and avian chronic or reproductive Rat Bobwhite Quail LOEC = ppm food NOEC = 2230 ppm food Fish, acute Rainbow Trout 96 hr. LC50 = 0.85 mg/l FW invertebrate, acute Daphnia magna 96 hr. LC50 = 4.8 mg/l Marine/estuarine acute Spot 96 hr. LC50 = mg/l FW invertebrate, chronic Daphnia magna 21 day LOEL = mg/l -5 FW fish, chronic Fathead Minnow 28 day LOEL = 0.9 x 10 mg/l Green Algae, acute Skeletonema costatum LC50 = mg/l Macrophyte, acute Lemna gibba LC50 = 4.83 mg/l LOEL < 2.54 mg/l Propiconazole does not appear to have any adverse effects on soil microbes as evidenced by soil biochemical analyses. Propiconazole displayed no toxic effects to earthworms. There are no current data on the effects of propiconazole on non-target insects such as honeybees, however there have been no previous incidents reported before the request for change in label.

9 Ms. Susan Person 9 Risk Assessment: Models were run to determine toxicities to birds, mammals, fish, and aquatic organisms. The avian and mammalian risk models (AVTOX and MAMTOX) were run with standard parameters using residue values derived from a maximum application rate of 0.9 lbs AI/acre. Both models showed that applied as labeled, the propiconazole in Tilt was unlikely to be harmful to birds or mammals. The fish and aquatic organisms models (PONDTOX) was run with two scenarios. In the first scenario, it was assumed that 25% of applied propiconazole was lost to foliar intercept, the amount of rainfall was 1 inch in a 10 acre field, 3% of the applied pesticide was dissolved in runoff, 100% of the runoff water reaches the pond. The application rate modeled was the maximum application rate of 0.9 lbs AI/acre. The Skeletonema costatum LC50 was exceeded in the 1ft deep pond and its NOEC was exceeded in the 1ft and 3ft deep ponds. The fathead minnow chronic NOEC was exceeded at all depths. In the next scenario, the same assumptions applied, except that 0% of applied propiconazole was lost to foliar intercept and 3% of applied pesticide was dissolved in runoff. The application rate modeled was the highest single application rate of lbs AI/acre. In this model, no risk threshold was exceeded at any depth. At the single application rate with the highest percent of applied pesticide dissolved in runoff, propiconazole is safe to all aquatic organisms tested. At the maximum application rate with 25% of the pesticide being lost to foliar intercept, propiconazole poses some risk to algae and to the chronic fathead minnow. Risk Analysis: Propiconazole has been found to be practically nontoxic to most non-target organisms including mammals and birds; however it is highly toxic to some fish and aquatic organisms. Due to its uses and application methods, propiconazole will not be likely to pose a threat to the aquatic environment as long as it is not applied directly to water as stated on the label. Propiconazole is applied directly onto plants to prevent or treat fungus and therefore will be intercepted and not as available for runoff. Also due to the moderately high soil-binding ability of propiconazole, chances of the pesticide reaching a body of water are greatly reduced. In the event that this pesticide does reach a body of water, the risk thresholds which were exceeded, were only exceeded minimally and thus will only pose a slight threat before undergoing degradation. Given the above, the BOH has no objections to registration. REGISTRATION CONCLUSION: The Department concludes that the use of Tilt 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 accepts the label and supplemental label for Tilt (EPA Reg. No ) for registration in New York State. Enclosed for your files are the Certificate of Pesticide Registration and New York State stamped ACCEPTED labeling. Please note that a proposal by Syngenta Crop Protection, Inc., or any other registrant to register a product containing propiconazole, whose labeled uses are likely to increase the potential for significant exposure 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 specified in 6 NYCRR Part

10 Ms. Susan Person 10 Please contact Samuel Jackling, Chief of our Pesticide Product Registration Section, at (518) , if you have any questions. Enclosures Sincerely, Maureen P Serafini Maureen P. Serafini Director Bureau of Pesticides Management ecc w/enc.: R. Mungari - NYS Dept. of Ag. & Markets A. Grey/E. Horn - NYS Dept. of Health W. Smith - Cornell University, PSUR

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