Although we still have to be careful about situations where there is still a risk of high levels of absorption of the most commonly known metals or where there is exposure to rare metals but with known toxicity, in the current transition phase from macro- to micro-doses of industrial toxics and metals in particular, it seems appropriate to encourage the development of study criteria and methods for this special field of occupational medicine. A number of aspects of the analytical techniques (ICP MS, in vivo measurements) are therefore discussed which should make for a better evaluation of doses; reference values for toxic metals intended as indispensable terms of evaluation of abnormal exposure to be related with any response by the human organism; identification and quantification of certain early effects that are of significant theoretical and practical interest, such as effects on the functional reserve and immunotoxic effects. Occupational medicine should take renewed interest in toxicological problems which, in the authors' view, have wrongly been considered outdated by the evolution of work-related diseases. On the contrary, this evolution calls for fresh and more in-depth interest also in occupational toxicology research.