[Interactions of toxic trace elements with special regard to selenium]

The significance of the trace elements in nutrition is often decisively affected by the interaction of trace elements with other trace elements and of trace elements with other substances. These processes, which include synergistic and antagonistic effects, are of great importance not only to the essentiality, but also to the toxicity of trace elements. There is considerable experience with interactions of essential elements. There is considerable experience with interactions of essential elements or of elements in essential concentrations. On contrast, there is a scarcity of information pertaining to toxic effects that are influenced by synergisms and antagonisms. This situation is illustrated by some examples and especially by the role of selenium. It is shown that these problems deserve closer attention.