Effects of deltamethrin and thiacloprid on cell viability, colony formation and DNA double-strand breaks in human bronchial epithelial cells.

Deltamethrin (DEL) and thiacloprid (THIA) are commonly used insecticides applied either separately or as a mixture. We aimed to investigate the effects of DEL and THIA on cell viability, proliferation and DNA damage in human bronchial epithelial cells (BEAS-2B) because their effects in lung cells are not known. Our results indicate that all concentrations of DEL and THIA statistically decreased colony formation, plating efficiency and survival fraction in a concentration-dependent manner in BEAS-2B cells expect the lowest concentration for 24 h. MTT assay showed that treatment of DEL + THIA increased the cytotoxicity at higher concentrations. DEL + THIA significantly induced the foci formation of phosphorylated H2AX protein and p53 binding protein 1 at the highest concentration (44 μM DEL+666 μM THIA) for 120 h. Because gH2AX foci number was still higher in the recovery group given an additional 24 h after 120 h, the recovery period was not sufficient for DNA double-strand breaks repair.