RED-BLOOD-CELL DAMAGE BY WOLLASTONITE - IN-VITRO STUDY

Asbestos is known to cause lung diseases in occupationally exposed wor kers. These properties have restricted its use. Industries have been e xploring the possibility of other mineral fibres to replace the asbest os. In this direction, wollastonite has gained great attention owing t o its high thermal resistance. In the present paper, the toxicity of t hree samples of Indian wollastonite was compared to that of chrysotile . Dust suspensions were added to the red blood cell suspensions to obt ain a final dust concentration of 1.0-5.0 mg ml(-1) in the system. The wollastonite varieties were found to have smaller haemolytic potentia l in human red blood cells than that of chrysotile in vitro. Chrysotil e also was more effective in inducting peroxidative damage of polyunsa turated fatty acid (PUFA) than wollastonites in the present system. Th e peroxidative damage of PUFA and the haemolysis were both time and do se dependent. A higher value of malonaldehyde (a lipid peroxidation pr oduct) formation in low-speed supernatant of haemolysate was observed than in the intact cells. As the free-radical scavengers vitamin E and reduced glutathione prevent haemolysis and lipid peroxidation, these data are consistent with the involvement of lipid peroxidation in the haemolytic process.