Cytotoxic, genotoxic, oxidative, and irritant effects of zinc pyrithione in vitro

Abstract Zinc pyrithione is an organometallic compound with antimicrobial activity used in many industrial products. In this study, cytotoxicity (cell viability, lactate dehydrogenase release, proliferation rate, and mitotic index) and genotoxicity (sister chromatid exchange and micronucleus test) of zinc pyrithione on human lymphocytes were determined. Intracellular zinc concentrations were determined by inductively coupled plasma-optical emission spectrometry. Intracellular antioxidant/oxidant status was evaluated by total antioxidant capacity and total oxidative status assays. Its irritation potential was investigated using the hen’s egg test chorioallantoic membrane model. Up to the highest concentration of 1000 nmol/L, ZnPT did not cause genotoxicity and did not change the proliferation index. Above 500 nmol/L, zinc pyrithione caused an increase in lactate dehydrogenase, oxidative stress, and intracellular zinc levels, while decreasing cell viability and mitotic index level. At 1000 nmol/L, zinc pyrithione caused slight irritation. These results suggest that zinc pyrithione may exert toxic effects via increased oxidative stress on human cellular systems.