Piperonyl butoxide mutagenicity in human RSa cells.

Piperonyl butoxide (PB) is used as a pesticide synergist and food additive. Its chemically induced mutagenicity was found in cultured human RSa cells by determination of ouabain-resistant (Ouar) phenotypic mutation, with the highest frequency at the concentration of 0.2 microgram/ml. Moreover, K-ras codon 12 mutations in genomic DNA, analyzed by polymerase chain reaction (PCR) and differential dot-blot hybridization using digoxigenin-labeled probes, were detected in RSa cells 6 days after exposure to PB (0.03-0.40 microgram/ml).