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Chloroethane
Description: Chloroethane (C.A.S. 75-00-3) is a man made compound that is a colorless gas at room temperature and pressure, with a characteristic, sharp odor. The largest single use for chloroethane is the production of tetraethyl lead, which is a gasoline additive. Chloroethane is also used as a solvent, as a refrigerant, and in the production of ethyl cellulose, dyes, medicinal drugs, and other commercial chemicals. It is also used to numb skin prior to medical procedures such as earpiercing and skin biopsy, and in sports injuries. Chemical properties: Synonyms for chloroethane include ethyl chloride and monochloroethene. In pressurized containers, chlorethane exists as a liquid that quickly evaporates when exposed to room air. It catches fire easily. It is soluble in alcohol and ether. Most of the chloroethane released to the environment ends up as a gas in the atmosphere, while much smaller amounts enter groundwater as a result of filtration through soil. Once in the atmosphere, chloroethane breaks down fairly rapidly by reaction with substances in the air. It takes about 40 days for half of any given amount of chloroethane that is released to the atmosphere to disappear. Synonyms for chloroethane are ethyl chloride; aethylis; aethylis chloridum; anodynon; chelen; chlorene; chlorethyl; chloridum; chloroethane; chlorure d'ethyle (DOT french); chloryl; chloyryl anesthetic; cloretilo; cloruro de etilo (DOT spanish); dublofix; ethane, chloro-; ethane, chloro-; ether chloratus; ether hydrochloric; ether muriatic; ether, hydrochloric; hydrochloric ether; kelene; monochlorethane; monochloroethane; muriatic ether; narcotile; nci-c06224; r 160; and un1037 (DOT). Identification: Health effects: Sources of human exposure to chloroethane include process and fugitive emissions from its production and use as a chemical intermediate; evaporation from wastewater streams, landfills, solvents, refrigerants, and anesthetics; emissions from plastics, refuse, and biomass combustion; inadvertent formation during water chlorination; and evaporation and leaching from landfills. Brief exposure to high levels of chloroethane vapor can produce temporary feelings of drunkenness, and at still higher levels, lack of muscle coordination and unconsciousness. Accidental death has resulted from its medical use as an anesthetic during major surgery. It is not known whether chloroethane produces cancer in humans. Though humans are typically exposed to very low levels of chloroethane, potentially high levels of exposure could result from occupational exposure, exposure at or near hazardous waste sites, and frequent contact with consumer products that contain chloroethane, such as solvents, paints, or refrigerants. Exposure Values: Economics: U.S. manufacturers of chlorethane are Dow Chemical USA, Freeport, TX; E I du Pont de Nemours & Co, Inc, Deepwater, NJ; Ethyl Corp., Pasadena, TX; Hercules Incorporated, Hopewell, VA; and PPG Industries, Lake Charles, LA. Regulation: EPA's Office of Emergency and Remedial Response oversees regulations and guidelines applicable to chloroethane. The Occupational Safety and Health Administration (OSHA) has established permissible exposure limits for chloroethane. Under Section 313 of the Emergency Planning and Community Right to Know Act of 1986, releases of more than one pound of chloroethane into the air, water, and land must be reported annually and entered into the Toxic Release Inventory Update OSHA Permissible Exposure Limit (PEL) TWA 0.5 mg/m3 [skin]. Under Section 313 of the Emergency Planning and Community Right to Know Act of 1986, releases of more than one pound of chlorine into the air, water, and land must be reported annually and entered into the Toxic Release Inventory (TRI). Facilities having a threshold quantity of 10,000 lbs of chlorethane are subject to the Risk Management Program Rule (RMP), Section 112r of the 1990 amendments to the Clean Air Act. National Overview of 1998 Toxics Release Inventory See EPA's Toxic Release Inventory. Notations: The NIOSH recommended exposure limits (RELs) are time-weighted average (TWA) concentrations for up to a 10-hour workday during a 40-hour workweek. A short-term exposure limit (STEL) is designated by "ST" preceding the value; unless noted otherwise, the STEL is a 15-minute TWA exposure that should not be exceeded at any time during a workday. A ceiling REL is designated by "C" preceding the value. Any substance that NIOSH considers to be a potential occupational carcinogen is designated by the notation "Ca." The OSHA permissible exposure limits (PEL) are found in Tables Z-1, Z-2, and Z-3 of the OSHA General Industry Air Contaminants Standard (29 CFR 1910.1000). Unless noted otherwise, PEL are TWA concentrations that must not be exceeded during any 8-hour workshift of a 40-hour workweek. A STEL is designated by "ST" preceding the value and is measured over a 15-minute period unless noted otherwise. OSHA ceiling concentrations (designated by "C" preceding the value) must not be exceeded during any part of the workday; if instantaneous monitoring is not feasible, the ceiling must be assessed as a 15-minute TWA exposure. In addition, there are a number of substances from Table Z-2 (e.g., beryllium, ethylene dibromide, etc.) that have PEL ceiling values that must not be exceeded except for specified excursions. For example, a "5-minute maximum peak in any 2 hours" means that a 5-minute exposure above the ceiling value, but never above the maximum peak, is allowed in any 2 hours during an 8-hour workday. Information Sources:
Originally published in Environment Writer by the National Safety Council. Reprinted with permission. Environment Writer Metcalf Institute for Marine and Environmental Reporting University of Rhode Island Graduate School of Oceanography Office of Marine Programs Narragansett, RI 02882 Tel: 401-874-6211; Fax: 401-874-6485 Disclaimer * Copyright 2002-2006 * All rights reserved. * University of Rhode Island |