Increased input of the fuel oxygenate methyl tert-butyl ether (MTBE) into the environment has posed serious risks to human health and the environment. This paper reviews current MTBE research with a heavy emphasis on the environmental behavior and fate of MTBE, and toxicity evaluation and risk characterization. Initial studies indicated that a large amount of MTBE is released to the atmosphere and it will be susceptible to photoxidation with an estimated half-life of 4 days. MTBE is biodegradable under aerobic conditions, but little or no anaerobic degradation of MTBE has been found. Based on current MTBE toxicological data, MTBE has been recognized as the animal carcinogen and no strong evidence has been found to indicate the carcinogenic potential of MTBE for humans. MTBE is toxic to various aquatic organisms at high exposed dosages (>7.4 mg·L-1),low exposed levels of iv1TBE (<0.1 mg·L-1) seem unlikely to have toxicity to those species. Few studies have been reported in toxicity of MTBE to terrestrial plants. Broadly speaking, full evaluation of toxicity of MTBE would require more comprehensive studies with special attention to chronic and sablethal toxicity to those species of lives.
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