title: Barium chromate is cytotoxic and genotoxic to human lung cells.
abstract: Hexavalent chromium (Cr(VI)) compounds are widely accepted as human lung carcinogens. However, there have been few investigations of the genotoxicity of Cr(VI) in human lung cells. Moreover, our knowledge of the effects of Cr(VI) in human lung cells is further limited because the available data generally focus on the effects of only lead chromate (PbCrO(4)) and sodium chromate (Na(2)CrO(4)). To fully understand these carcinogenic compounds, the genotoxic effects to its target cells need to be evaluated for additional Cr(VI) salts. Accordingly, we investigated the cytotoxicity and clastogenicity of barium chromate (BC) in a human lung cell culture model (WTHBF-6 cells). We found that BC induced concentration-dependent cytotoxicity in WTHBF-6 cells, with relative survival of 88%, 74%, 67%, 12%, 3%, and 0.1% after exposure to 0.01, 0.05, 0.1, 0.5, 1, and 5 microg/cm(2) BC, respectively. Similarly, the amount of chromosomal damage also increased with concentration after a 24-h exposure. Specifically, 0.01, 0.05, 0.1, and 0.5 microg/cm(2) BaCrO(4) damaged 5%, 9%, 22%, and 49% of metaphase cells, with the total damage reaching 5, 10, 28, and 65 aberrations per 100 metaphases, respectively. Concentrations of 1 and 5 microg/cm(2) BC induced a profound cell cycle delay, and no metaphases were observed. The spectrum of damage included chromatid and chromosome-type lesions consistent with mechanistic events associated with the activation of oncogenes and inactivation of tumor suppressor genes. Overall the data indicate that BC is cytotoxic and genotoxic to human lung cells.
authors.affiliation: Center for Integrated and Applied Environmental Toxicology, Wise Laboratory of Environmental and Genetic Toxicology, Bioscience Research Institute, University of Southern Maine, Portland, Maine 04104-9300, USA.
authors.forename: Sandra S
authors.initials: SS
authors.lastname: Wise
authors.forename: Julie H C
authors.initials: JH
authors.lastname: Schuler
authors.forename: Spiros P
authors.initials: SP
authors.lastname: Katsifis
authors.forename: John Pierce
authors.initials: JP
authors.lastname: Wise
mesh_terms: D001464:Barium / Q000633:toxicity*; D017609:Barium Compounds / Q000633:toxicity*; D002453:Cell Cycle / Q000187:drug effects; D002460:Cell Line; D002840:Chromates / Q000633:toxicity*; D002857:Chromium / Q000633:toxicity*; D002869:Chromosome Aberrations / Q000139:chemically induced; D002875:Chromosomes / Q000187:drug effects; D004249:DNA Damage; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000187:drug effects; D006801:Humans; D008168:Lung / Q000187:drug effects*; D008677:Metaphase / Q000187:drug effects; D013997:Time Factors
chemical_list: D017609:Barium Compounds; D002840:Chromates; D002857:Chromium; C074702:chromium hexavalent ion; D001464:Barium; C481392:barium chromate