Low levels of occupational exposure to arsenic and antimony : effects on lysosomal glycohydrolase levels in plasma of exposed workers and in lymphocyte cultures

Background In the present study, the activities of lysosomal glycohydrolases were determined in order to evaluate the asymptomatic toxic effects of low levels of exposure to arsenic and antimony in art glass workers. Methods N-acetyl-ß-D-glucosaminidase, ß-D-glucuronidase,  and -D-galactosidase, -D-glucosidase, and -D-mannosidase were determined by a fluorimetric assay in the plasma of 26 art glass workers. Lymphocytes cultured in the presence of different species of arsenic and antimony served as an in vitro model for the study of the protective action of selenium and zinc. Results No significant difference in the plasma levels of the various enzymes was detected in art glass workers or control subjects. The in vitro experiments demonstrated that secretion of lysosomal glycohydrolases was increased by antimony (225%) and decreased by arsenic (57%) at the same concentration of elements(200 µg/L). The addition of bivalent selenium to the culture neutralized the effects of both metals, while zinc chloride did not show any protective effect. Conclusions As for the plasma glycohydrolases, no praecox signs of toxicity related to a low concentration of arsenic and antimony was evident in art glass workers. This may be due to the antagonistic effects demonstrated by these two metals in vitro. Their different mechanism of action on release of glycohydrolases is being discussed.