Vinyl Chloride

This work evaluates the risks to human health and the environment posed by exposure to vinyl chloride, a colourless, flammable gas manufactured almost exclusively for use in the production of polyvinyl chloride (PVC). A chapter on sources of human and environmental exposure covers production levels and processes, noting the geographical expansion of production plants to South East Asia, Eastern Europe, the Indian subcontinent, and oil-producing countries.

Production technologies that lead to lower residual levels of PVC are also briefly described.

Concerning human exposure, the report concludes that atmospheric concentrations in ambient air are low, resulting in very little exposure of the general population. A chapter on kinetics and metabolism in laboratory animals and humans finds that vinyl chloride is rapidly absorbed and widely distributed following exposure via the inhalation and oral routes.

An assessment of effects on humans draws on clinical findings following accidental exposures, supported by a large number of epidemiological studies of occupationally-exposed workers.

These studies provide strong and consistent evidence that vinyl chloride causes the rare tumour, angiosarcoma of the liver. On the basis of this analysis, the report calls for measures to minimize emissions at production sites and sanitary landfills, and to ensure low residual levels in PVC.

Moreover, as vinyl chloride is a known carcinogen, the report stresses the need to keep occupational exposures as low as possible and to educate workers about the risks involved and the need for safe working procedures.