Background Chemistry of Molybdenum
Conclusions
In its general chemistry molybdenum is very different from the common toxic heavy metals such as cadmium, lead, and mercury. Molybdenum is ingested, transported, and excreted as an anion [MoO4]2- which is structurally similar to phosphate and sulfate. Molybdenum has a number of stable oxidation states and so participates in redox processes. Molybdenum forms relatively weak and labile complexes with physiologically important compounds, especially those with hydroxy- and carboxy-groups and also has affinity for compounds with amino and thiol groups. Thus molybdenum, while having an essential biochemical role in various redox processes, does not combine sufficiently strongly with physiologically important compounds to have a serious blocking effect on metabolic processes and so its toxicity, certainly with regard to human beings, is low.
