METALS AND THE SKIN

Certain metals, and many metal-based compounds, are inherently toxic, and their presence in occupational and environmental settings raises a ppropriate questions concerning human exposure. Contact of these mater ials with the skin represents an important route of exposure, which is not well characterized. The purpose of this review, therefore, is to assemble the available, useful information pertinent to risk assessmen t following dermal contact. Specifically, we summarize here: (1) data relevant to the qualitative and (where possible) quantitative evaluati on of metal compound permeation through the skin; (2) the role of each metal in metabolism, particularly with respect to the skin, and the p otentially toxic effects that may result from dermal contact; and (3) the immunological characteristics (including allergenicity) of the met als and their derivatives. In total, information on 31 metals has been reviewed. It is clear that many diverse factors determine the ability of metal-based species to permeate biological membranes, not all of w hich have been fully defined. Therefore, considerably more experimenta tion, targeted at the development of high-quality transport data, will be required before the specification of practically useful structure- activity relationships are possible.