Environmental mutagens in urban air particulates

Abstract

A bioassay capable of detecting carcinogenic substances that are associated with the elevated incidence of cancer in the urban environment would be important for epidemiologic and environmental analyses. The feasibility of using the Salmonella mutagenesis system developed by Ames for this purpose has been tested by analyzing Chicago air particulate samples. Active material, as evidenced by enhanced rates of mutation, both in the presence of microsomes and in their absence, is readily extractable from samples of air particulates. Dose-response curves have been obtained from such extracts of 15 successive samples, taken at intervals during 1975 from a sampling site in South Chicago. A method for analyzing such data in order to evaluate the relative mutagenic activity of different samples is described. The presence of a number of mutagenic constituents has been demonstrated by means of thin-layer chromatography of particularly active samples, in which the active material is located by mutagenic analysis of successive chromatographic zones. Mass spectrometer analysis of material isolated from an original sample in this way indicates that benzo[a]pyrene and benzo[e]pyrene, which are known to be mutagenic and carcinogenic, are present. It is concluded that within certain constraints, which are described, the methodology can serve the purpose of an environmental bioassay for organic carcinogens.

Induction of sister chromatid exchanges and bacterial revertants by organic extracts of airborne particles

“…Early fetal deaths were observed in mice treated with certain fractions of extracts of airborne particles, indicating mutagenicity to germ cells (Epstein et al, 19721. Transformation of rodent cells in vitro by extracts of airborne particles was demonstrated [Gordon et al, 19731. Data on mutagenicity in vitro have been obtained from the Salmonella/ mammalian microsome (Ames) assay [Ames et al, 19751, which showed that organic extracts of particulates from urban and industrial sources and/or their fractions induce gene reversions in bacteria [see, for example, Commoner et al, 1978; Chrisp and Fisher, 1980; Daisey et al, 1980;Preidecker, 1980;Tokiwa et al, 19801. used alone, because it is a procaryotic test system from which results cannot readily be extrapolated to man and because of inadequacies of endogenous and exogenous metabolic activation, a problem of all in vitro assays. Hughes et a1 [1980] recommended that a battery of bioassays, including the sister chromatid exchange (SCE) assay [Perry and Evans, 1975; Solomon and Bobrow, 1975; Wolff, 19771, should be applied to air pollutants.…”

Evidence for Space-Time Clustering of Lung Cancer Deaths

“…3 Weiss 4 also reported a potential correlation between lung cancer death rates, total settled dust, and sulfate concentration in Philadelphia. Coupling this epidemiologic evidence with the report of mutagenicity of air samples in an urban area by Commoner et al 5 further emphasizes the possible role of air pollution in lung cancer.…”

An Ultrahigh Volume Sampler for the Multiple Filter Collection of Respirable Particulate Matter

“…9 This is particularly important in mutagen bioassay since the small particles have been found to have higher content of mutagenic material. 10 Other possible problems are reentrainment into the air stream during arcing and the ozone produced by the corona discharge. Particulate components may be susceptible to alteration by the electrostatic field as well.…”