[Multiple occupational exposure to solvents].

This article review papers published over the last 20 years on multiple occupational exposure to solvents. At low-levels of exposure the toxicokinetic interferences between solvents have generally not been observed in man and presumably a threshold limit exists. Conversely, at exposure levels close to the "limit values" metabolic interference has sometimes been observed and the behaviour of the biological indicators differs from what would be expected. Toxicodynamic interference between solvents can give rise to additive, potentiation, synergistic, antagonistic effects. For the identification of "limit values", it has generally been suggested in the literature that the possible effects deriving from multiple exposure be considered as additive. However, numerous potentiation effects have frequently been reported for combined exposure to substances of widespread use. In this paper lists of multiple exposure in which the doses of the substances, the types of interferences and the behaviour of the biological levels have been drawn up and proposed as a tool for easy consultation.