[The infraclinical diagnosis of lead poisoning (author's transl)].

Laboratory study of 16 workers handling lead made it possible to define a state of infraclinical lead poisoning. Estimation of alpha-dehydrase and of free erythrocytic protoporphyrins is the most sensitive test for diagnostic purposes. The estimation of erythrocytic pyrimidine 5' Nucleotidase would seem to be of value in the diagnosis of mild lead poisoning. The urinary lead tolerance test confirms the diagnosis and indicates the degree of intoxication. Its repetition make it possible to treat the intoxication.