Clastogenicity of lead chromate particles in hamster and human cells.

Journal Article

Several insoluble compounds of chromium, such as lead chromate, are respiratory carcinogens in experimental animals and suspected to be so in humans. Lead chromate induces neoplastic transformation in cultured cells but the mechanism of genotoxicity is unknown. We examined the effect of lead chromate on the integrity of chromosomes of Chinese hamster ovary (CHO) and human foreskin fibroblasts (HFF) after a 24-h exposure. At 0.4 microgram/cm2, 0.8 microgram/cm2, 2 microgram/cm2 and 8 microgram/cm2 lead chromate particles reduced survival of CHO cells to 86%, 62%, 2% and less than 1% respectively. These concentrations induced a dose-dependent 4-19-fold increase in the percent metaphases with damage. The HFF cells exhibited higher sensitivity in both cytotoxicity and clastogenicity. The spectrum of damage observed for both cell types was primarily achromatic lesions affecting one or both chromatids. To test for particle dissolution effects, CHO cells were treated for 24 h with either clarified medium that had been incubated for 24 h with lead chromate particles, or clarified medium that had been pre-conditioned by CHO cells treated with lead chromate particles for 24 h. No damage was detected in these cells, indicating that extracellular dissolution into ionic lead and chromate did not contribute to the genotoxicity. This is consistent with a previous study in which scanning electron micrographs illustrated internalization of the particles. These results suggest that clastogenesis may be a mechanism for lead chromate induced carcinogenesis.

Full Text

Duke Authors

Cited Authors

  • Wise, JP; Leonard, JC; Patierno, SR

Published Date

  • January 1992

Published In

Volume / Issue

  • 278 / 1

Start / End Page

  • 69 - 79

PubMed ID

  • 1370121

Electronic International Standard Serial Number (EISSN)

  • 1873-135X

International Standard Serial Number (ISSN)

  • 0027-5107

Digital Object Identifier (DOI)

  • 10.1016/0165-1218(92)90287-a

Language

  • eng