METHOXYCHLOR FACT SHEET ON A DRINKING WATER CHEMICAL CONTAMINANT GENERAL INFORMATION Synonym*: • 2,2-Bis(4-Methoxyphenyl)-l ,1,1 -Trichloroethane; DMDT; Methoxy-DDT • Trade Names: Marlate; Evershield CM and T; Flo Pro McSeed Protectant Chemical Description: • Chlorinated insecticide Properties: • Pale yellow crystalline solid at room temperature • Low solubility in water Production and Use: • Used to control insects on fruit and shade trees, vegetables, dairy and beef cattle, home gardens, around buildings, and in streams ENVIRONMENTAL PROFILE Occurrence: • Not likely to be a common contaminant of ground water or surface water derived drinking water supplies Releases: • Enters surface water as a result of runoff from treated fields or by direct application • May enter ground water from direct entry into a well through accidental chemical spills or improper storage near a well Environmental Fate: • Moderately persistent in the environment: • not likely to volatilize significantly from soil, but may be significant from surface waters • immobile in soil (binds tightly to soil), and is resistant to leaching from soils; low potential to migrate to ground water • will adsorb to suspended particles and sediment in surface waters • may be subject to photodecomposition in some surface waters • will be removed from soils primarily oy biodegradation • May bioaccumulate in some aquatic organisms HEALTH EFFECTS Humans: • Little data on human studies Experimental Animals: • Short-term, high-dose studies indicate that methoxychlor has a low acute toxicity • symptoms of toxicity include central nervous system (CNS) depression, progressive weakness, .diarrhea, loss of appetite, fatty degeneration in the liver, kidney, and heart muscle .• rapidly excreted by the body • Long-term, high-dose studies caused growth retardation, and decreased body we-gnrs (weights return to normal after exposure s ceased) • No teratogenic or fetotoxic effects reported • Equivocal evidence of mutagenic potential • Not considered carcinogenic in animals REGULATORY PROFILE Existing Standards: •Clean Air Act (CAA): Not regulated •Clean Water Act (CWA): Criteria established •Resource Conservation and Recovery Act (RCRA); Hazardous waste •Superfund (CERCLA): •Hazardous substance •SARA: Toxic chemical •Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA): Registered •Toxic Substances Control Act (TSCA): Not regulated ------- HEALTH INFORMATION Maximum Contaminant Level Goal* (MCLG): • Non-enforceable levels based solely on an evaluation of possible health risks and exposure, and taking into consideration a margin for public safety • Set at 0.04 mg/L to protect against damage to the liver, kidneys, and nervous system MCLG for Methoxychlor = 0.04 mg/L (effective July 1992) Maximum Contaminant Levels (MCL): • Legally enforceable levels for contaminants in public drinking water supplies • Based on health risks associated with the contaminants, analytical methoas for their assay, and water treatment feasibility and practicality aspects • Exceedance of the MCL in drinking water may result in adverse effects which will depend upon the contaminant concentration in water, amount of water/contaminant ingested, length of exposure, and other biological parameters • Current MCL = 0.1 mg/L MCL for Methoxychlor = 0.04 mg/L (effective July 1992) EPA Health Advisories (HA): • Short-term HAs: Provide acceptable concentrations of contaminants in water for up to 10 day exposures, primarily to evaluate the public health risk resulting from an accidental spill or an emergency contamination situation • Longer-term HAs: Provide guidance for persistent water contamination situations to cover a period of up to 7 years • Lifetime HAs: Derived in the same way as an MCLG Health Advisories: • Gas Chromatography T with an Electron Capture Detector EPA Method 508 • Liquid-Solid Extraction and Capillary Column Gas Chromatography/Mass Spectrometry EPA Method 525 WATER TREATMENT Permanent Treatment: • Best Available Technology (BAT): • Granular Activated Carbon SHORT-TERM HAZARD ELIMINATION • If the drinking water standards are exceeded, install BAT or use an alternative drinking water supply such as bottled water ADDITIONAL HELP • State or county health officials can indicate a certified laboratory for testing • Experts in the state Department of Environmental Protection, Natural Resources, or Agriculture may also be of help • The EPA has toll-free numbers for further information on drinking water quality, treatment technologies, for obtaining Health Advisories, and for other regulatory information • EPA Hotlines are available Monday through Friday •Safe Drinking Water 800-426-4791 •National Pesticides: 800-858-7378 •Superfund/RCRA: 800-424-9346 • For information on the Clean Water Act, call (202) 260-7301 • For information on the Toxic Substances Control Act, call (202) 554-1404 • For information on the Clean Air Act, call (919) 541-2777 Short-term HA for a chHd = 2.0 mg/L Longer-term HA for a child = 0.5 mg/L Longer-term HA for an aduit = 0.2 mg/L Lifetime HA = 0.04 mg/L ANALYTICAL METHODS • Microextraction and Gas Chromatography EPA Method 505 ------- |