nitrogen-dioxide and propylene

The mutagenic activities of mixtures of nitrogen dioxide and 1,3-butadiene or propene were investigated after uv-irradiation in a small, laboratory-bench scale flow-through gas exposure system. The tester organism was Salmonella typhimurium, principally strain TA100. The photoreaction products from 1,3-butadiene and nitrogen dioxide were more mutagenic than those from propene and nitrogen dioxide. Approximately 0.25 ppm butadiene, compared to 100 ppm propene, was needed to give a significant mutagenic effect with 0.25 ppm NO2 after 6 hr exposure. The influence of different experimental conditions on mutagenic activity was studied using propene plus nitrogen dioxide. Increasing the mean reaction time from 40 min to 1 hr 20 min or 3 hr 20 min by reduction of the flow rate through the 20-liter reaction vessel did not appreciably increase the sensitivity of the system, nor did humidification of the air, omission of the metabolic system (S9 mix), or spreading of the bacteria on the agar surface. Prolongation of the exposure time from 6 to 16 or 24 hr did, however, give an increased mutagenic response. With prolonged exposure, a slight mutagenic effect could also be detected with ethene + NO2 + uv. Ozone addition did not appreciably enhance the mutagenic response.

Topics: Alkenes; Butadienes; Drug Interactions; Mutagenicity Tests; Mutagens; Nitrogen Dioxide; Salmonella typhimurium; Ultraviolet Rays

A study was made on the genetic effects of the photochemical reaction products of propylene plus NO2 on cultured Chinese hamster V79 cells with the use of sister chromatid exchanges (SCE). The photochemical reaction products of propylene plus NO2 were produced by photochemical reaction of a propylene-NO2/dry air system in a photochemical smog chamber and then were exposed to cell cultures for 2 h. SCEs were induced at all concentrations of the photochemical reaction products employed in the present study, the frequency of SCEs being two or three times higher than that of the controls. The genetic effects of NO2 and ozone (O3) were also studied and compared with those of the photochemical reaction products of propylene plus NO2. NO2 and O3 both induced SCEs in V79 cells, but their effects were weaker than those induced by the photochemical reaction products of propylene plus NO2. It was ascertained that the photochemical reaction of the propylene-NO2/dry air system produced much stronger genotoxic factors than the reactants.

Topics: Air Pollutants; Alkenes; Animals; Cells, Cultured; Cricetinae; Cricetulus; Nitrogen Dioxide; Ozone; Photochemistry; Sister Chromatid Exchange

Topics: Acetylene; Air Pollution; Alkenes; Chemistry Techniques, Analytical; Ethylenes; Hydrocarbons; Nitrogen; Nitrogen Dioxide; Plants