Evaluates the risks to human health and the environment posed by exposure to benzene, a naturally occurring chemical found in crude petroleum and manufactured in extremely large quantities worldwide. The presence of benzene in gasoline and in cigarette smoke, combined with its widespread use as an industrial solvent, has resulted in the presence of this chemical in the environment. Because benzene is a well-established human carcinogen, the book gives particular attention to data relating patterns, levels, and duration of exposure to health hazards in both the general population and exposed workers. A section on sources of exposure identifies emissions from motor vehicles as the largest source of this chemical detected in the general environment. For indoor environments, data show that cigarette smoke results in the exposure of non-smokers as well as smokers to important levels of benzene. Tthe report concludes that most humans are exposed to trace levels, with much higher levels seen in cigarette smokers, those exposed to sidestream smoke, residents in areas of heavy automobile traffic, and workers involved in the production, handling, and use of benzene and its derivatives. The most extensive section reviews the large number of toxicity studies of benzene. Particular attention is given to the numerous animal studies demonstrating carcinogenicity and exploring the mechanisms by which benzene damages bone marrow and exerts its other toxic effects. The remaining sections assess the risks to human health posed by benzene in both the general population and in exposed workers, giving particular attention to the numerous epidemiological and case studies that have established benzene as a human leukaemogen. Because the health risk of low-level benzene exposure is not yet clearly established, the report concludes that exposure should be avoided as much as possible.

eng with summary and conclusions in fre and spa.

WHODOC

WHO monograph

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