Genotoxicity of aerosol extracts. Some methodological aspects and the contribution of urban and industrial locations.

The genotoxicity of aerosol extracts was investigated with the Ames test and an SCE test in vitro. In addition to experiments to evaluate current techniques, a so-called gradient study was carried out in an industrialized part of The Netherlands to obtain insight into the contribution of urban and industrial locations to the genotoxicity of aerosol extracts. The influence of variations in the sampling was investigated. The results indicate that moderate variations in the volume of air sampled per unit of time and of the duration of the sampling period do not have a great influence on the effect measured. Experiments with filters impregnated with 14C-labelled benzo[a]pyrene showed that this compound is converted during sampling into directly active mutagens; no evaporation occurred. The results of experiments to evaluate the extraction procedure indicated that an 8-h Soxhlet extraction with methanol is better than, or as good as, Soxhlet extraction with other solvents. The gradient study showed that the aerosol downwind from industrial/urban areas exerted a reproducibly stronger effect in the Ames test and the SCE test when compared with aerosol from sea air.