Chromosomal aberrations and sister-chromatid exchanges induced by gaseous nitrogen dioxide in cultured Chinese hamster cells.

Effects of gaseous nitrogen dioxide (NO2) on chromosomal morphology of cultured Chinese hamster V79-H3 cells were investigated. Chinese hamster cells were exposed to NO2 gas in N2 gas at NO2 concentrations of 0, 5, 10, 20, 50 and 100 ppm (v/v) for 10 min at a gas flow rate of 1000 ml/min. Both chromosomal aberrations and sister-chromatid exchanges were increased depending on the NO2 concentration. The effects of sodium nitrite (NaNO2) were also examined in comparison with those of gaseous NO2, and it was found that the effects of gaseous NO2 could not be ascribed to those of nitrous acid. The gas-exposure apparatus used in this experiments seems to be useful for quantitative investigation of the effects of various gaseous materials on cultured mammalian cells or bacterial cells.