CYTOTOXIC AND GENOTOXIC EFFECTS OF CALCIUM SILICATES ON HUMAN-LYMPHOCYTES INVITRO

Calcium silicate has been considered as a possible replacement for asb estos due to its heat and fire resistance. We describe the cytotoxic a nd genotoxic potential of calcium silicate using peripheral human bloo d lymphocytes. Calcium silicates at concentrations of 10 and 100 mug/m l significantly increased the frequencies of chromosomal aberrations ( CAs) and sister-chromatid exchanges (SCEs). The increases in CAs and S CEs were dose-dependent, though not linearly. A significant decrease i n the proliferation rate index was observed with increased dose of cal cium silicates. The induction of chromatid-type aberrations indicates that the clastogenic activity of calcium silicate is S-phase-dependent .