Proi cthM offjc, ^ ftttUki* IV Washington. DC 2O46O Pesticide Fact Sheet Name of Chemical: PHOSALONE Reason for Issuance: REGISTRATION STANDARD Date Issued: NOVEMBER 30, 1937 Fact Sheet Number: 148 1. DESCRIPTION OF CHEMICAL Generic Name: S-6-chloro-2,3-#ihydro-2-oxobenzoxazol-3-yl (Chemical) methyl 0,0-diethyl phosphorodithioate Common Name: Phosalone (ANSI) Other Chemical Nomenclature: °S-[(6-chloro-2-oxo-3(2H)benzoxazolyl)methyl] 0,0-diethylphosphorodithioate; °0,0-diethyl phosphorodithioate S-ester with 6-chloro- 3-(mercaptomethyl)2-benzoxazolinone; °0,0-diethyl-S-[(6-chloro-2-oxobenzoxazolin-3-yl) methyl]phosphorodithioate; °S-[6-chloro-3-(mercaptomethyl)-2-benzoxazolinone] 0,0-diethylphosphorodithioate; „ °0,0-di ethyl-S-C 6-chloro-3-(mercaptomethyl)-2-benzoxazolinone] phosphorod i th i oat e. Trade Names: Azonfene, Benzofos, RP11974, Rubitox, and Zolone. EPA Shaughnessy Code: 097701 Chemical Abstracts Service (CAS) Number: 2310-17-0 Year of Initial Registration: 1974 Pesticide Type: Insecticide/Acaricide Chemical Family: Organophosphate U.S. and Foreign Producers: Rhone-Poulenc, Inc. 2. USE PATTERNS AND FORMULATIONS Application Sites: Nut crops, citrus crops, pome fruits, stone fruits, grapes, potatoes, artichokes, roses, and arborvitae. Formulation Types: Technical, Emulsifiable Concentrate and Wettable Powder. Application Methods: Foliar: ground and aerial application. ------- 2 3. SCIENCE FINDINGS Summary Science Statement Phosalone may have an adverse impact on birds and aquatic organisms resulting from all use patterns, excluding ornamentals. Aquatic and terrestrial field studies are required to determine the potential risks to these organisms. Laboratory data show that technical phosalone is highly toxic to fish .and aquatic invertebrates. The toxicological profile of the end—use products places them in Toxicity Category II for primary eye irritation, acute oral and dermal exposures. The end—use products were only mildly irritating to the skin when tested for dermal irritation. The products were characterized as weak dermal sensitizers. Phosalone can cause adverse effects to persons entering treated fields and to persons involved in the preparation and application of this pesticide. Preliminary data show that groundwater contamination is unlikely, but the Agency is unable to conduct a full assessment due to data gaps. Chemical/Physical Characteristics of the Technical Material Physical State: Crystalline solid Color: White Molecular weight and formula: 367.8 gms—C 12 H 15 C1NO 4 PS 2 Melting Point: 45—47°C Density: 1.391 g/ml at 20°C Vapor Pressure: < 0.5 x 10—6 mm Hg at 24°C and 16.4 x 10-6 at 60°C Solubility: At 20°C: l.7ppm in water; 20 g/lOO ml in methanol and ethanol; and lOg/lOOmi in acetone, benzene, cyclohexanone, acetonitrile, xylene, toluene, dioxane, chloroform, and methyl chloride. Stability: Very stable under normal laboratory conditions for a period of 2 years. ------- 3 Toxicology Characteristics (Technical Material) Acute Oral: Toxicity Category II (90 and 125 mg/kg in female and male rats respectively). Acute Dermal: Toxicity Category II ( LD5O > 350 mg/kg for both males and females). Acute Inhalation: Waived for technical, particles analyzed were determined not to be within the respirable range ( < 15 microns). Primary Dermal Irritation: Toxicity Category IV (PDIS—O.77, mildly irritating to intact and abraded skin). Primary Eye Irritation: Data gap. Skin Sensitization: Data gap. Delayed neurotoxicity: Negative in hens. Subchronic Oral (non-rodent): Data gap. Oncogenicity: Data gap. Chronic Feeding: NOEL for RBC inhibition in the rat is 25 ppm. Metabolism: Data gap Teratogenicity: Data gap Reproduction: Data gap Mutagenicity: Data gap for point mutation assay in mammalian cells, structural chromosomal aberration, and other genotoxic effects. Major routes of exposure: Dermal and respiratory exposure to mixers, loaders, applicators, and fieldworkers. Environmental Characteristics Phosalone is stable at pH 5 and 7, but is hydrolyzed at a pH of 9 with a half—life of 9 days. Artificial light accele- rated degradation in buffered solution at a pH of 5 and in soil. Aerobic soil metabolism studies demonstrate half—life values of 1—7 days. Field dissipation studies showed half—life values of 1—9 weeks. Phosalone was essentially immobile in a soil column test. Based upon this preliminary data phosalone appears unlikely to contaminate ground water. It exhibited moderate accumulation in the bluegill sunfish, with rapid dissipation in untreated waters. ------- 4 Ecological Characteristics (Technical grade) Aviai Oral Toxicity: Slightly toxic to w terfowl (acute oral toxicity value: mallards > 2150 mg/kg). Avian Dietary Toxicity: Slightly toxic to waterfowl and upland- 8—Days) game birds (subacute toxicity values: mallards 1659 ppm and bobwhite quail 2033 ppm). Freshwater Fish Acute: Very highly toxic to warmwater fish and Toxicity ( 96—Hours) and highly toxic to coidwater fish (acute LC values: 0.05 ppm bluegill and 0.63 ppm rainbow- trout). Freshwater Invertebrate: Very highly toxic to aquatic invertebrate Toxicity (48—Hours) (acute EC value: 0.0012 ppm Daphnia magna ) 4. Tolerance Reassessment Tolerances have been established for phosalone on a variety of raw agricultural commodities, in meat, fat and meat byproducts (40 CFR 180.263) and in processed food (21 CFR 193.340) and feed (21 CFR 561.300). Tolerances for the following commodities are adequately supported: potatoes, citrus, apples, pears, apricots, cherries, nectarines, peaches, plums (fresh prunes), dried prunes, tree nuts, almond hulls, grapes, raisins, artichokes, and the fat, meat, and meat byproducts of cattle, goats, hogs, horses and sheep. Additional data are required to assess the need for food! feed additive tolerances for the following products processed from raw agricultural commodities bearing measurable, weathered residues: potato granules or flakes, chips, and wet and dry peels, raisin waste and grape juice. ------- 5 The nature of the residues in both plants and animals are not adequately understood. If, on receipt of the required metabolism data, the Agency determines that residues in additi.on to the parent require regulation, additional methods for data collection and enforcement may be required. Crop group tolerances may be proposed for the Pome Fruit Group at 10 ppm and for the Stone Fruit Group at 15 ppm. The Agency has established a Provisional Acceptable Daily Intake (PADI) at 0.0025 mg/kg/day based on a 6—month dog feeding study in which plasma cholinesterase activity was depressed. Because a NOEL was not established in this study a 100 fold uncertainty factor has: been used rather than the 10 fold factor normally applied for cholinesterase inhibition. 5. Summary of Regulatory Positions and Rationales °Phosalone is not being placed into Special Review at this time. Although the Agency is concerned about the potential adverse impact of phosalone on birds and aquatic organisms resulting from the agricultural use patterns, aquatic and terrestial field studies are needed in order to evaluate the potential risks to these species. °The Agency has sufficient data (analysis of pesticides with similar uses were found to be in jeopardy) to indicate that the current use patterns of phosalone may affect endangered species. Endangered species labeling is reserved pending concurrence from the Fish and Wildlife Service. °The Agency is classifying all Phosalone end use products as Restricted Use Pesticides; except for products packaged and labeled solely for use around the home. Products containing phosalone for use on cherries and citrus are restricted due to avian hazards. All use patterns are restricted due to aquatic toxicity. The estimated environmental concentrations exceed the LC5O value for fish and the EC5O value for aquatic invertebrates, and the NOEL values for avian species. °The Agency is imposing a 6—month rotational crop restric- tion for small grains and a 12—month rotational crop restriction for leafy vegetables and root crops. ------- 6 °No significant new tolerances or new food uses will be granted until the Agency has received sufficient data to evaluate the dietary exposure of p iosalone. °The Agency will retain the 24—hour reentry interval imposed in the 1981 Registration Standard. This reentry in- terval will be retained until the required reeentry data are received and evaluated. Data will be reviewed on a priority basis because of reported poisoning incidents in California. °The Agency will require that end use products bear label statements to protect mixers, loaders, applicators, flaggers, and fieldworkers. °Preliminary data indicate that groundwater contamination is unlikely. The Agency is requiring environmental fate studies to fully characterize phosalone’s fate in the environment. 6. SUMMARY OF OUTSTANDING DATA REQUIREMENTS Time Frame Toxicology Primary Eye Irritation 9 Months Dermal Sensitization 9 Acute Inhalation 9 “ Subchronic oral toxicity——Dog (for cholinesterase 12 effects) Oncogenicity-—rat 50 Teratogenicity—-(rat and rabbit) 15 Reproduction—-(rat) 39 Mutagenicity 12 Metabolism study 12 Dermal Absorption (rat) 9 Environmental Fate/Exposure Aged leaching study 12 Rotational Crop (Confined) 12 Foliar dissipation study 15 Spray Drift 12 Soil Dissipation 27 ------- 7 Fish and Wildlife Aviari reproduction 24 Months Actual field testing— birds and mammals (citrus) 30 Simulated or Actual field testing—aquatic organisms 48 Acute toxicity to Estuarine and Marine organisms 12 “ Fish early life stage and aquatic invertebrate life cycle 15 Acute toxicity to Freshwater Invertebrate 9 Residue Chemistry Animal and Plant metabolism 18 Months Storage stability 15 Processing studies for potatoes and grapes 24 Residue data (tea) 18 Product Chemistry 6-15 Months 7. CONTACT PERSON AT EPA Dennis H. Edwards, Jr. Product Manager (12) Insecticide—Rodentjcjde Branch Registration Division (TS—767C) Office of Pesticide Programs Environmental Protection Agency 401 M Street, S. W. Washington, D. C. 20460 Office location and telephone number: Room 211, Crystal Mall #2 1921 Jefferson Davis Highway Arlington, VA 22202 (703) 557—2386 DISCLAIMER: The information presented in this Chemical Infor- mation Fact Sheet is for informational purposes Only and may not be used to fulfill data requirements for pesticide regis- tration and reregistration. ------- COMMUNICATIONS STRATEGY FOR PHOSALONE ACTION: Registration Standard, issued under the provisions of Sect-ion 3(g) of FIFRA PROPOSED ISSUANCE DATE: October, 1987 AGENCY REVIEW: This document has been reviewed by OPPE, OGC, 0CM, AA/OPTS, and OPP offices (RD, HED, PMSD, BUD). GROUPS AFFECTED BY THE STANDARD: This document requires registrants of all products containing phosalone to generate data to replace missing or inadequate studies, and to revise labels to reflect the addi- tional precautions required in the standard. There are 4 FIFRA section 3 end-use products, one technical product, and 1 FIFRA section 24(c) special local need registrations. The basic producer of phosalone is Rhone—Poulenc, Inc. OTHER GROUPS TO RECEiVE COPIES OF THE STANDARD: Copies of the Standard will be sent by the Registration Support and Emergency Response Branch (RSERB), RD to EPA regional offices, Agriculture/Canada, and Health Canada. Copies of the standard will be sent by OPP8 state coordinator to each state. Additional copies are available to the public ------- —2— through NTIS. The public is notified of the availability of the Registration Standard through per.iodic announcement in the Federal Register. BACKGROUND INFORMATION: The fact sheet, attached, summarizes the Registration Standard. RSERB maintains a mailing list for the fact sheet. An announcement will be placed in the Federal Register shortly which will provide people the opportunity to put their name on the fact sheet mailing list. AGENCY CONTACT PERSON: Dennis H. Edwards Product Manager (12) Insecticice—Rodenticide Branch Registration Division (TS—767) Environmental Protection Agency Washington, D.C. 20460 Phone: (703) 557—2386 ------- |