[Relationship of environmental levels, respiratory absorption and urinary concentrations of various solvents: effects of work load].

The physical demand in the workplaces can be different depending on each specific job. This involves that workers exposed to the same environmental level of an airborne can absorb different amounts of it depending on their pulmonary ventilation. Starting from the relationship between the uptake (U) and the urinary concentration (Cu) of 6 solvents (Acetone, Styrene, Xylenes, Toluene, Methylchloroform, Tetrachloroethylene) and from the equation expressing their lung uptake the expected values of a biological index after a given time of exposure can be derived. Such values are a function not only of the environmental levels of exposure (CI) but also of the pulmonary ventilation (V) (V--dependent solvents) and of the retention index (R) (V--R--dependent solvents).