Are metals dietary carcinogens?

Humans have been in contact with metals almost since the beginning of our e xistence. In fact, one cannot even think on human evolution without conside ring the great role played by metals in mankind's development. Metals are c ommon moieties of molecules involved in a wide variety of biological proces ses, and hence are found in virtually all Living organisms. Some metals are essential for human nutrition; others are found as contaminants in foodstu ffs. One feature of the normal human diet which is frequently found is the simultaneous presence of both essential and toxic metals. Other factors imp ortant in the risk-evaluation analysis of metals are their pharmacokinetics , interactions among them and with other major components of the diet, and, especially, the great differences in the dietary habits of different popul ations and in the regional distribution of metals. In attempting to underst and the role which dietary metals could play in human carcinogenesis, we fo und that the many factors involved and the lack of specific information mad e it difficult to reach firm conclusions on the hazards of dietary metals. We hope that this paper will raise the interest of genetic toxicologists in the subject and will consequently facilitate a risk analysis of the carcin ogenic potential of dietary metals. (C) 1999 Elsevier Science B.V. All righ ts reserved.