Emission of carcinogenic components with automobile exhausts.

Abstract

Different sampling methods for mutagenic polynuclear aromatic hydrocarbons (PAH) are described. These methods involve either direct sampling of raw exhausts which prior to filtering are cooled in a condenser, or filter sampling of exhausts diluted in a tunnel. The relevance of gas-phase PAHs of samples from diluted exhausts is discussed; methods used are either adsorbents (XAD-2) or cryogenic condensation. The emission of benzo(a)pyrene and certain other PAHs is reported from vehicles using different fuels (gasoline, diesel, LPG, alcohols) or different emission control systems. The emission of some volatiles, such as benzene, ethylene and alkylnitrites, is also presented from different types of fuels used.

Profiles of Organic Particulate Emissions from Air Pollution Sources: Status and Needs for Receptor Source Apportionment Modeling

“…If the data reported by Stenberg 31 are excluded from the comparison, then the ratios of the PAH/BeP for the exhaust condensates, for compounds beyond pyrene agree within a factor of 3 or less, despite differences in sampling and analytical methods. Furthermore, the ratios for the exhaust condensates generally are in agreement with those determined for the tunnel samples.…”

“…The type of engine (spark ignition, diesel), the presence of a catalytic converter, the driving cycle, age of the vehicle, and hot versus cold starts are all factors which can affect the emissions. 30 ' 31 Thus, the collected samples are not generally representative of average on road conditions for a mixed fleet of motor vehicles. Tunnel samples provide more useful profiles for receptor source apportionment modeling as they are representative of the average composition for motor vehicles.…”

Association of childhood cancer with residential traffic density.

“…One of the few established causes of adult leukemia is benzene (5), whereas other solvents are suspected of causing leukemia (6) and possibly brain cancer (7). Evidence that benzene in gasoline produces detectable concentrations in the ambient air as high as 10-20 ug/rn ' in urban areas (8,9) makes this potential consequence of traffic density worthy of evaluation, along with the contribution of motor vehicles to environmental lead and hydrocarbon levels. Data from a study designed to examine electromagnetic fields and childhood cancer were used to assess whether any of these exposures might be related to childhood cancer incidence in Denver, Colorado.…”

Applicability of a Cryogradient Technique for the Enrichment of PAH from Automobile Exhausts: Demonstration of Methodology and Evaluation Experiments

“…A comprehensive review of different sampling methods for PAH from automobiles is presented *Department of Analytical Chemistry, University of Stockholm, Arrhenius Laboratory, S-106 91 Stockholm, Sweden. elsewhere in this issue (1). Only some principles will be described here.…”