CORRELATION OF ASBESTOS-INDUCED CYTOGENETIC EFFECTS WITH CELL-TRANSFORMATION OF SYRIAN-HAMSTER EMBRYO CELLS IN CULTURE

  • 1 January 1984
    • journal article
    • research article
    • Vol. 44  (11) , 5017-5022
Abstract
The cytogenetic effects of chrysotile asbestos on Syrian hamster embryo cells in vitro were investigated at doses which induced morphological and neoplastic transformation but which failed to induce measurable gene mutations in the cells at 2 genetic loci. Chrysotile asbestos treatment of the cells significantly induced chromosome changes in a dose-dependent manner. Up to 50% of the cells had chromosome abnormalities in number or structure following treatment with asbestos (2.0 .mu.g/sq cm) for 48 h. Numerical chromosome changes were the most pronounced abnormalities although significant increases in metaphases with other chromosome aberratios (breaks, fragments, exchanges and/or dicentrics) and cells with binuclei or micronuclei were also observed. A linear relationship was observed between the incidences of cells with tetraploid metaphases and binucleated cells, suggesting that binucleation and tetraploidy are related. Cytogenetic effects of other mineral dusts were also tested 48 h following treatment at a concentration of 2.0 .mu.g/cm2. Crocidolite asbestos was less potent than chrysotile asbestos in its ability to induce cell transformation and cytogenetic damage. Treatment of the cells with thin glass fibers (Code 100) was also able to induce cell transformation and cytogenetic effects, but thick glass fibers (Code 110) were much less potent for both endpoints. Milling of the thin glass fibers decreased the length of the fibers and abolished their ability to induce cell transformation and cytogenetic effects. Nonfibrous .alpha.-quartz induced neither cell transformation nor cytogenetic effects at the dose of 2.0 .mu.g/cm2. The physical characteristics of the fibers evidently determine their ability to induce cell transformation and their ability to induce chromosome mutations, suggesting a possible mechanistic relationship. [Implications with respect to the increased risk of lung cancer in workers exposed to asbestos were presented.].