Inhaled ozone as a mutagen: II. Effect on the frequency of chromosome aberrations observed in irradiated Chinese hamsters

Abstract

Exposure-adjusted break frequencies for chromosome aberrations produced in Chinese hamster circulating blood lymphocytes were the quantitative indicator of damage from 5 hours of exposure to x-radiation (118 keV effective, 70 cm FSD, 230 rad) and/or to ozone (0.2 ppm, uv generated). There were two groups of four per treatment plus one group exposed to 330 rad. Radiation produced 5.51 × 10 −4 breaks/cell rad for cells withdrawn 2 weeks after exposure, a reasonable value when compared with data from in vivo exposure of human lymphocytes and Chinese hamster bone marrow cells. Animals exposed to the two agents simultaneously exhibited >70% of the total breaks anticipated assuming the expected equal contributions (See Part 1) to be additive. Extending to humans, at presently permitted levels, exposure to ozone would be much more detrimental than exposure to radiation.