Cytogenetic effects of permethrin in cultured human lymphocytes

The pyrethroid insecticide permethrin was tested for its ability to induce sister chromatid exchanges (SCE), micronuclei (MN) and structural chromosome aberrations (CA) in cuItured human peripheral blood Iymphocytes. Permethrin was tested in the range of 5 500 i.ig/ml in the absence and in the presence of a rat liver activation system (S9 mix). Small elevations in the SCE frequencies were found and even though statistica lly significant may ha ve no biological meaning, the more so since there was no dose-effect relationship. Permethrin induced both MN and CA when it was evaluated in the absence of a metabolic acti vation system. Nevertheless, it cannot be said that S9 mix suppressed the activity in itself. The effect of permethrin seemed to be time of exposure dependento Permethrin could be characterized as a S-phase independent agent with greater potential for inducing chromosomal damage than sister chromatid exchanges.