Translations in French and Spanish of chapters 1, 10 and 11.

Evaluates the risks to human health and the environment posed by the production and use of fully halogenated chlorofluorocarbons. Eight different commercial compounds, some of which are known to contribute to ozone depletion, are assessed. The opening section summarizes the unique chemical and physical properties that account for the commercial importance of chlorofluorocarbons and explain why their degradation in the upper stratosphere destroys ozone. Subsequent sections summarize data on the global distribution of chlorofluorocarbons and evaluate the strength of evidence suggesting that increased ultraviolet-B radiation, resulting from ozone depletion, will endanger terrestrial and aquatic biota. The report concludes that even small increases in ambient ultraviolet-B exposure can result in significant ecosystem changes. The second half of the book evaluates health risks associated with both direct exposure, mainly through inhalation during production, and the far more important indirect effects of ozone depletion. A review of extensive experimental data supports the conclusion that direct exposure entails low toxicity and little or no carcinogenic risk. Concerning the consequences of increased exposure to ultraviolet-B radiation, the book notes documented and potential risks that include a virtually undisputed increase in the incidence of non-melanoma skin cancers, an increase in the incidence of cutaneous melanomas, possible suppression of the immune system, and an increase in the incidence of cataracts. The report concludes with an eight-point agenda for further research and a call for cuts of at least 80-90% in the emission of ozone-depleting chlorofluorocarbons.

eng.

WHODOC

WHO monograph

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