Immunotoxicology: review of current status

Our need to understand the potential adverse human health effects of environmental chemical exposure has coincided with an increased understanding of the immune system and an appreciation of its complex regulatory network. This has spawned a broad interest in the area of immunotoxicology within the scientific community as well as certain concerns in the public sector regarding chemical-induced hypersensitivity and immunosuppression. The incidence of alleged human sensitization to chemicals has increased, in part, due to the fact that chemical companies are moving to larger and/or different markets. It has been estimated that 35 million Americans suffer from allergic disease of which 2% to 5% are from occupational exposure. Although there is not yet a clear understanding of dose-response relationships or disease predisposition, there are many well-defined examples (isocyanates, anhydrides) of chemical sensitizers in humans and experimental animals. Evidence that chemicals suppress immune responses in humans is considerably less well established, although there is a public perception that chemicals generally cause immunosuppression. This perception has been fueled by highly publicized legal cases (ie, W.R. Grace and Agent Orange) and scientific controversies within the academic and industrial communities (Aldicarb). As a consequence of public pressure, the regulatory agencies are considering immunotoxicity testing guidelines. At the present, however, there are limitations on adequate human methodology and data that allow the extrapolation of animal data to assess accurately human risk.(ABSTRACT TRUNCATED AT 250 WORDS)