Interactions between selenium compounds and those of mercury or cadmium.

Two types of mechanisms are considered in this discussion of the interactions between compounds of selenium and those of cadmium or mercury: one based on a direct chemical reaction between compounds of these elements and the other based on metabolic changes induced by selenium administration and modifying the dose-effect relationship indirectly, without a reaction between selenium and the metallic compound. The second type of metabolic changes induced by selenium may explain why an increased selenium intake provides protection not only against methylmercury but also against the toxicity of methylated selenium compounds. A better understanding of the underlying mechanisms would help in assessing the importance of these interactions for man.