United States Environmental Protection Agency Office of Water 4601 EPA811-F-95-003p-T October 1995 Primary Drinking Water Regulations Ethylene Dibromide CHEMICAL/ PHYSICAL PROPERTIES CAS NUMBER: 106-93-4 COLOR/ FORM/ODOR: Colorless; heavy liquid; mildly sweet chloroform-like odor. M.P.: 9.8° C B.P.: 131-132° C VAPOR PRESSURE: 11.2 mm Hg DENSITY/SPEC. GRAV.: 2.2 g/ml OCTANOL/WATER PARTITION (Kow): LogKow = 135 > SOLUBILITIES: 40 g/L of water at 25° C SOIL SORPTION COEFFICIENT (Koc): low to moderate; Koc = 14 to 160 ODOR/TASTE THRESHOLDS: N/A BIOCONCENTRATION FACTOR: <1 in fish HENRY'S LAW COEFFICIENT: N/A TRADE NAMES/SYNONYMS: 1,2-Dibromoethane; EDB; Glycol dibromide; Bromofume; Dowfume W 85; Aadibroom; Iscobrome-D; Nefis; Pestmaster; EDB-85; Soilbrom; Soilfume; Kopfume DRINKING WATER STANDARDS MCLG: zero mg/l MCL: 0.00005 mg/l HAL(child): 1 day: 0.008 mg/l 10-day: 0.008 mg/l HEALTH EFFECTS SUMMARY Acute: EPA has found ethylene dibromide (EDB) to potentially cause a variety of acute health effects, includ- ing damage to the liver, stomach, and adrenal cortex along with significant reproductive system toxicity, par- ticularly the testes. Drinking water levels which are considered "safe" for short-term exposures: For a 10-kg (22 Ib.) child consum- ing 1 liter of water per day, a one-day exposure of 0.008 mg/L or a ten-day exposure to 0.008 mg/L. Chronic: A lifetime exposure to EDB at levels above the MCL has the potential to damage the respiratory system, nervous system, liver, heart, and kidneys. Cancer: There is some evidence that EDB may have the potential to cause cancer from a lifetime exposure at levels above the MCL. USAGE PATTERNS Ethylene dibromide is mainly used (83% of all use) as a scavenger for lead in anti-knock gasoline mixtures, particularly in aviation fuel. Other uses (17%) include: solvent for resins, gums, and waxes; in waterproofing preparations; as a chemical intermediate in the synthesis of dyes and Pharmaceuticals; and as a fumigant, insec- ticide, nematicide for grains and fruit. RELEASE PATTERNS - Monitoring of ethylene bromide in ocean water and ocean air suggests that ethylene bromide may be formed naturally in the ocean as a result of macro algae growth. Artificial releases include: evaporative losses associ- ated with the use, storage, and transport of leaded gasoline in which it is used as a lead scavenger; spills and leaking storage tanks for leaded gasoline; exhaust from vehicles using leaded gasoline; emissions from its former use as a fumigant for soil, grain, fruits, vegetables, tobacco, and seed uses which have recently been re- stricted or discontinued; wastewater and emissions from its use as a solvent for resins, gums, and waxes and; as a chemical intermediate in the synthesis of dyes and Pharmaceuticals; residue in fumigated food. \ From 1987 to 1993, according to the Toxics Release Toxic RELEASE INVENTORY - RELEASES TO WATER AND LAND: 1987 TO 1993 Water TOTALS (in pounds) 2,554 Top Six States CA 344 MS 342 HI 750 NJ 0 TX 110 PR 500 Top Industrial Sources Petroleum refining 2,119 Industrial organic 355 chemicals, fertilizers Land 2,670 500 500 0 700 466 0 1,716 700 October 1995 Technical Version ------- Inventory EDB releases to land totalled 2,670 Ibs., and water releases totalled 2,554 Ibs. These releases were primarily from facilities classified as petroleum refineries. The largest of these releases occurred in California and Missouri. ENVIRONMENTAL FATE When spilled on land or applied to land during soil fumigation, ethylene dibromide will exhibit low to moder- ate adsorption and has been found in groundwater. Measured KOC values range from 14 to 160. However, in typical fields where gaseous ethylene ,dibromide has been used as a soil fumigant, 99% of the ethylene dibromide used in fumigation is in the sorbed state. Persistence can vary greatly from soil to soil. In one laboratory screening study using 100 soils, half-lives ranging from 1.5 to 18 weeks were determined. In one field, ethylene bromide was detected in soil 19 years after its last known application; the long persistence was the result of entrapment in intraparticle micropores of the soil. Low Koc values and detection in various ground waters indicate that ethylene bromide will leach in soil. The relatively high vapor pressure (11.2 mm Hg) indicates evaporation will occur from soil surfaces. In the atmosphere, ethylene dibromide will degrade by reaction with photochemically produced hydroxyl radi- cals (half life 32 days). The primary removal process for ethylene bromide in surface water is volatilization. Under normal conditions, the volatilization half-life from a typical river and lake are about one day and 5 days, respectively. In ground waters (such as aquifers) where volatiliza- tion does not occur, ethylene bromide can be degraded by biodegradation and hydrolysis. Uncatalyzed hydroly- sis is slow, with half-lives reported of 6 yr at 25 deg C, to 13.2 yr at pH7 and 20 deg C. But hydrolysis catalyzed by the presence of various natural substances (such as HS ion) may be competitive with biodegradation (half-life of 1-2 months). It reacts with photochemically produced hydroxyl radicals with a half life of 32 days or a 2.2% loss per sunlit day. Ethylene bromide does not directly photo- lyze when exposed to uv light between 300 and 400 nm. Biodegradation can be a primary degradation process in soil. A review of available biodegradation data pertain- ing to ethylene bromide concluded that ethylene bromide is biotransformed fairly readily in the environment; life- times can be as short as several days in surface soils and as long as many months in aquifer materials. The measured log BCF in fish is < 1 indicating that ethylene dibromide does not bioconcentrate in fish. OTHER REGULATORY INFORMATION MONITORING: FOR GROUND/SURFACE WATER SOURCES: INITIAL FREQUENCY- 4 quarterly samples every 3 years REPEAT FREQUENCY- If no detections during initial round: 2 quarterly per year if serving >3300 persons; 1 sample per 3 years for smaller systems TRIGGERS - Return to Initial Freq. if detect at > 0.00001 mg/L ANALYSIS: REFERENCE SOURCE METHOD NUMBERS EPA 600/4-88-039 504.1; 551 TREATMENT: BEST AVAILABLE TECHNOLOGIES Granular Activated Charcoal FOR ADDITIONAL INFORMATION: * EPA can provide further regulatory and other general information: • EPA Safe Drinking Water Hotline - 800/426-4791 * Other sources of lexicological and environmental fate data include: • Toxic Substance Control Act Information Line - 202/554-1404 • Toxics Release Inventory, National Library of Medicine - 301/496-6531 • Agency for Toxic Substances and Disease Registry - 404/639-6000 • National Pesticide Hotline - 800/858-7378 October 1995 Technical Version Page 2 ------- |