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Methyl Ethyl Ketone
Description: Methyl ethyl ketone (C.A.S. 78-93-3) is a colorless liquid with an acetone-like odor. It is used as a solvent for coatings, adhesives, magnetic tapes, printing inks, and pesticide formulations; as an extraction solvent for hardwood pulping and vegetable oil; as a fragrance and flavoring agent in candy and perfumes; as a catalyst in the production of hydrazine; and as a sterilizer for bacterial spores on surgical instruments, hypodermic needles and syringes, and dental instruments. It is used in surface coating, fabric coating, lacquering, and varnishing. It is used in the manufacture of colorless synthetic resins, smokeless powder, artificial leather, lubricating oils, paint removers, cements, adhesives, and cleaning fluids. Chemical properties: Methyl ethyl ketone is soluble in water, alcohol, ether, acetone, and benzene. It is lighter than water and may be expected to float while rapidly dissolving. It is incompatible or reactive with strong oxidizers, amines, ammonia, inorganic acids, caustics, copper, isocyanates, and pyridines. Synonyms for methyl ethyl ketone are 2-butanone, ethyl methyl ketone, methyl acetone, and MEK. Idenfication: Health effects: Methyl ethyl ketone can cause human health effects through inhalation, ingestion, and contact with the skin. Since methyl ethyl ketone is a natural component of some foods, ingestion of food is also a source of exposure. Its health effects are similar to but more irritating than acetone (EW, January, 1992). Its vapor is irritating to mucous membranes and conjunctiva. Exposure can irritate the eyes, nose, and head; it can cause dizziness, fatigue, memory alteration, dermatitis, headaches, nausea, paresthesia of extremities, diminished vision, acidosis, and vomiting. Prolonged exposure can cause central nervous system depression. Economics: U.S. manufacturers of Methyl ethyl ketone are: Exxon Corp, New York, NY; Hoechst Celanese Corp, Somerville, NJ; and Shell Oil Co, Houston, TX. Exposure Values: Regulation: The Occupational Safety and Health Administration (OSHA) sets permissible exposure limits for methyl ethyl ketone of 200 ppm (590 mg/m3), time-weighted average, and 300 ppm (885 mg/m3), short-term exposure limit. Methyl ethyl ketone is regulated under the Emergency Planning and Community Right-to-Know Act; Clean Air Act, under National Emission Standards for Hazardous Air Pollutants; Comprehensive Environmental Response, Compensation, and Liability Act; Toxic Substances Control Act; Resource Conservation and Recovery Act; and Federal Insecticide, Fungicide, and Rodenticide Act. Under Section 313 of the Emergency Planning and Community Right-to-Know Act, releases of more than one pound of methyl ethyl ketone must be reported annually and entered into the national Toxic Release Inventory (TRI). 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 |