Formation and Fate of Gaseous and Particulate Mutagens and Carcinogens in Real and Simulated Atmospheres

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. The National Institute of Environmental Health Sciences (NIEHS) and Brogan & Partners are collaborating with JSTOR to digitize, preserve and extend access to Environmental Health Perspectives.The growing use of coal for heating and electric power generation and diesel engines in light duty motor vehicles will increase not only the existing atmospheric concentrations of criteria pollutants such as NO2, SO2, 03 and fine particulates, but also the concentrations of a number of highly reactive gaseous copollutants such as HONO, HONO2, PAN and the nitrate radical, NO3. These gaseous noncriteria pollutants are of interest not only because of their roles in the chemistry of the "clean" and polluted troposphere, including "acid rain," but also because they may pose health risks disproportionate to their relatively low ambient concentrations, and through complex heterogeneous reactions, they may serve as precursors or catalysts in the formation of "nonclassical" particulate mutagens and carcinogens such as certain nitroarenes associated with combustion generated particulate polycyclic organic matter (POM). Results of research efforts to establish current ambient levels of these noncriteria pollutants and to develop an understanding of their sources, formation and sinks are reported here. First, long pathlength (? 1 km) infrared and UV-visible spectroscopic studies of ambient levels of gaseous HONO, NO3, HONO2, PAN, HCHO and HCOOH in southern California atmospheres are described, and data given on their ambient concentrations. Second, an integrated chemical/microbiological investigation is described. It is directed toward identifying the nature of direct-acting mutagens found in extracts of diesel and ambient POM, as well as those formed upon exposure of environmentally relevant PAH to simulated natural and polluted atmospheres. The identification of certain of these mutagens, including a newly identified class of mutagenic PAH-lactones is discussed, along with the mechanisms of their formation and fate in the natural and polluted troposphere. organic matter (POM) believed responsible for its carcinogenicity in animals (4,5). Additionally, some attention would have been given to the fact that the activity [as well as the rates of transformation in cell cultures (6)] was significantly greater than could be accounted for by the amounts of wellknown carcinogenic PAH, such as benzo(a)pyrene (BaP), determined to be in the POM extracts (2,5,7-15). This "excess carcinogenicity" implied that carcinogenic compounds, as yet uncharacterized, must also be present.Today, yet another dimension has been added to the problem. Around 1975, with the development of the short-term Ames Salmonella typhimurium ...

Environmental Carcinogenic Polycyclic Aromatic Hydrocarbons: Photochemistry and Phototoxicity

“…The photochemical degradation of nitro-PAHs mainly leads to photo-oxidation products. The photochemical reaction rate of nitro-PAHs depends on the position of the nitro-substitution (82,(84)(85)(86)(87). Nitro groups peri to two hydrogen atoms is forced to be in a perpendicular orientation to the aromatic ring due to steric hindrance while nitro groups peri only to one hydrogen atom stay in a parallel orientation to the aromatic ring (18,22,33,83) (Figure 9).…”

A Dilution Stack Sampler for Collection of Organic Aerosol Emissions: Design, Characterization and Field Tests

“…Some of these organic compounds are known to be carcinogenic (IARC, 1980;Natusch, 1978) or mutagenic (Pitts, 1983;Schuetzle, 1983), but little is known about the contribution of specific emission sources to the ambient organic aerosol concentrations (Daisey et al, 1986).…”

Hygroscopic Growth of Assorted Indoor Aerosols

“…It also serves as a guide to the studies of their associated health effects. Many organic species found in fine aerosol are known to be carcinogenic and/or mutagenic (Daisey et al 1980;Pitts 1983;Schuetzle 1983;Gundel 1993). Inhalation of wood smoke leads to in-*Author to whom all correspondences should be addressed.…”