COMPARISON OF BIOLOGICAL EFFECTS OF DIFFERENT POLYCYCLIC AROMATIC-HYDROCARBONS IN LUNG-CELLS OF HAMSTER AND RAT IN-VITRO

The cytotoxicity and frequencies of transformation induced by 5 enviro nmental polycyclic aromatic hydrocarbons (PAH) in hamster (M3E3/C3) an d rat (WRB K3) lung cells were compared. Both cell strains investigate d here retain major metabolic characteristics of the target cells in v ivo and are thus able to effectively metabolize, i.e. activate, PAH. C ytotoxic effects of the carcinogen were determined in colony-forming a ssays and the PAH tested induced dose-dependent cytotoxic responses in the M3E3/C3 and WRB cells. They could then be classified into strong and weak cytotoxity. Compared to the hamster cell system, the WRB cell s were generally shown to be more sensitive. The transforming capacity of the compounds was determined by a soft agar colony formation assay detecting cells with anchorage independency (AI). All BAH investigate d induced transformation to AI growth in both cell systems. The transf orming activity of the PAH, relative to benzo[a]pyrene (B[a]P) as a re ference substance, was determined to facilitate their ranking. This or der of transforming potency appears to be similar to that observed in animal studies.