[Medical surveillance of people exposed to substances].

Medical surveillance is only one of the ways to estimate the health risk and to assure a good health for workers exposed to atmospheric polluting agents. Occupational practitioner defines himself the forms of this surveillance, according to the risks; excepted a few cases about which legislation determines the minimal contents. Without neglecting clinical exam, in spite of poor and late symptoms, an important place is reserved to biological monitoring: early detection of effects and dosing the product or its metabolites in biological fluids.