Toxicity of metallic ions and oxides to rabbit alveolar macrophages

The effects of soluble compounds and oxides of As, Cd, Cu, Hg, Ni, Pb, Sb, Sn, V, and Zn on oxidative metabolism and membrane integrity of rabbit alveolar macrophages were studied by 24-hr in vitro exposure. Oxidative metabolism induced by phagocytosis of opsonized zymosan was measured by H2O2 and O2- release and by chemiluminescence in the presence of luminol. Membrane integrity was estimated by extracellular LDH activity. Metallic ions and oxides inhibited the release of active oxygen species. Cd(II), As(III), and V(V) were the most toxic elements as measured by all investigated parameters. Cu(II) decreased O2- release and chemiluminescence effectively but H2O2 release and membrane integrity less. Chemiluminescence was decreased strongly by Hg(II) while O2- and H2O2 release were depressed moderately. Zn(II) and Sb(III) compounds caused medium toxicity and the tested Sn, Ni, and Pb compounds showed only faint toxic effects.