Genotoxicity and embryotoxicity of urban air particulate matter collected during winter and summer period in two different districts of the Czech Republic

This study is the in vitro part of a long-term program to investigate the i mpact of air pollution on the health of a population in a polluted region o f Northern Bohemia. In order to assess the possible health risks associated with a complex mixture of hundreds of organic compounds adsorbed to air pa rticles, we used a biomarker-directed fractionation procedure to evaluate b iological activities of different chemical compound classes. The extractabl e organic compounds from the air particles collected in both the polluted a nd the control districts during the summers and winters of 1993-1994 were i nvestigated. The principal aim of this study was to compare the DNA binding activities of those compound classes using an in vitro acellular assay cou pled with P-32-postlabeling and an embryotoxicity assay using Chick Embryot oxicity Screening Test (CHEST). In both assays, the highest activity was du e to the neutral fractions from which the aromatic subfractions containing mainly polycyclic aromatic hydrocarbons (PAHs) and their methyl-derivates w ere the most active for both localities and seasons. A good correlation bet ween the levels of DNA adduct formation using S9 metabolic activation and t he ED50 for all different complex mixtures of organic compounds was observe d (r = 0.773, p < 0.001). DNA adduct maps and high performance liquid chrom atography (HPLC) profiles were similar for samples from both districts and seasons. The major DNA adducts resulting from the crude extracts were ident ical to those derived from aromatic fractions. The DNA adducts tentatively identified constituted about 50% of the total adducts formed by the crude e xtracts following S9-metabolic activation. Our results confirmed the simila rities of the major ubiquitous emission sources of organic compounds in bot h districts. This is the first report in which the biological activities of complex mixtures in short-term assays with remarkably different endpoints such as DNA adduct formation and embryotoxicity have been compared. (C) 199 9 Elsevier Science B.V. All rights reserved.