In vitro and in vivo effect of mercury, lead and cadmium on the generation of chemiluminescence by human whole blood.

A method based on the use of the luminogenic substance, luminol, was developed for measuring the respiratory burst induced by phorbolmyristate acetate in 4 microliters of human whole blood. In vitro, the three cations, Hg2+, Pb2+ and Cd2+, inhibit the peak luminescence response at concentrations higher than those usually found in blood of subjects exposed to these metals. Cadmium metallothionein, however, in a concentration range similar to that found in whole blood of workers exposed to cadmium strikingly reduces the respiratory oxidative burst. In workers exposed to inorganic lead or mercury vapour, no reduction of the chemiluminescence response of whole blood was observed while a slight but statistically significant reduction was found in whole blood from cadmium exposed workers. If a similar effect occurs in lung macrophages, it might decrease the respiratory tract resistance to infection.