Human Skin Cells Are More Sensitive than Human Lung Cells to the Cytotoxic and Cell Cycle Arresting Impacts of Particulate and Soluble Hexavalent Chromium

Hexavalent chromium Cr(VI) is a known human lung carcinogen, with solubility playing an important role in its carcinogenic potency. Dermal exposure to Cr(VI) is common and has been associated with skin damage; however, no link between chromate exposure and skin cancer has been found. In this study, we compared the cytotoxic and clastogenic effects of Cr(VI) and its impacts on cell cycle progression in human lung and skin fibroblasts. We found human skin cells arrested earlier in their cell cycle and exhibit more cytotoxicity than human lung cells, despite taking up similar amounts of Cr. These outcomes are consistent with a hypothesis that different cellular and molecular responses underlie the differences in carcinogenic outcome in these two tissues.