Heat shock proteins (hsp) are a highly conserved group of proteins that are synthesized as a response to different forms of stress (heat, toxic chemicals, diseases, non-physiological pH changes). Because of their high sensitivity to changes in the environment, these proteins were suggested as possible early biomarkers of exposure in ecotoxicological studies. The purpose of the present study was to check the suitability of hsp 32 and hsp70 as biomarkers of in vitro exposure to environmentally relevant carcinogens: polycyclic aromatic hydrocarbons (PAHs), their nitro-derivates, aromatic amines, acrylonitrile (ACN) and the mixture of organic compounds adsorbed onto ambient airborne particles (extractable organic matter, EOM). The expression of hsp 32 and hsp70 was studied in human diploid lung fibroblasts (HEL cells) and human monocytic leukaemia cells (THP-1 cells) incubated in vitro with different concentrations of dibenzo[a,l]pyrene (DB[a,l]P), 1-nitropyrene, (NP), 4-aminobiphenyl (ABP), ACN and EOM for different periods of time. The incubation of cells with DB[a,l]P, NP, ABP and EOM did not result in increased levels of hsp 32 or hsp70, either in dose- or time-dependent manner. ACN induced the expression of hsp 32 as well as hsp70 in HEL and THP-1 cells, which probably reflects its ability to induce oxidative stress. We conclude that hsp 32 and hsp70 are not suitable biomarkers of an early exposure to PAHs, their nitro-derivates, aromatic amines or EOM under the conditions used.

Laboratory of Genetic Ecotoxicology Health Institute of Central Bohemia and Institute of Experimental Medicine AS CR Vídenská 1083 142 20 Prague 4 Czech Republic

Nucleotide excision repair is not induced in human embryonic lung fibroblasts treated with environmental pollutants