Toxicity of hexavalent chromium to the alveolar macrophage in vivo and in vitro.

In vivo and in vitro systems were used to evaluate hexavalent chromium toxicity to alveolar macrophages. Rat alveolar macrophages were exposed to 2 micrograms calcium chromate (CaCrO4, insoluble) or 2 micrograms chromium trioxide (CrO3, soluble) in live animals, in vivo, and in tissue culture, in vitro, collected by lavage from the lung. Chemiluminescence and oxygen consumption were measured as indicators of toxicity. Trypan blue dye exclusion was used to determine macrophage viability. In vivo exposure of the macrophage to either chromium compound showed no toxic effects at a 2-micrograms dose. Macrophages exposed in tissue culture, however, had values significantly different from controls. The untreated controls for both exposure methods were compared to evaluate differences resulting from methods alone.