In vitro genotoxicity studies of chrysotile asbestos fibers dispersed in simulated pulmonary surfactant.
Lu-J; Keane-MJ; Ong-T; Wallace-WE
Mutat Res 1994 Mar; 320(4):253-259
In-vitro investigations were carried out on the genotoxic effects of chrysotile (12001295) asbestos (CA) fibers dispersed in simulated pulmonary surfactant. Chinese-hamster lung V79 cells were challenged with unconditioned CA and with CA conditioned by incubation in dipalmitoyl-lecithin (DPL) to simulate pulmonary surfactant. The CA consisted of intermediate (ICA) and short length (SCA) fibers. After 48 hours of treatment, micronucleus (MNC) formation, multiple nuclei formation (MLC), and sister chromatid exchanges (SCE) were assayed. Results showed that all CA exposed cells had a significant elevation in MNC formations over the blank (DPL) treated controls. The frequencies of MNC in cells treated with DPL conditioned SCA was about twice as low as that in cells treated with unconditioned SCA. However, there were no significant differences with the ICA. The ICA induced higher frequencies of MLC than the corresponding SCA and DPL conditioned fibers were generally less active than unconditioned fibers. There was no dose related increase in SCE frequency induced by either CA samples, whether conditioned with DPL or not. The authors conclude that while exposure to both surfactant conditioned and unconditioned SCA and ICA induces MNC and MLC formation in pulmonary cells, conditioning with surfactant reduces CA cytotoxicity.
NIOSH-Author; Chromosome-damage; DNA-damage; Asbestos-fibers; Genotoxic-effects; Surfactants; Pulmonary-system; In-vitro-studies; Laboratory-animals; Lung-cancer;
Author Keywords: Chrysotile asbestos; Dipalmitoyl lecithin; Micronucleated cells; Multinucleated cells; Sister-chromatid exchange