Prallethrin tested negative in the majority of the genotoxicity studies. It also tested negative in an in vitro chromosomal aberration study in Chinese Hamster Ovary (CHO K1) cells without metabolic activation, but tested positive at all doses with metabolic activation. However, clastogenicity was not clearly dose-related, was seen at nontoxic and slightly toxic doses, and was not expressed in in vivo studies and structure-activity comparisons with the other pyrethroids revealed no correlations with clastogenicity. Other gene mutation, chromosomal aberration, and unscheduled DNA synthesis (UDS) studies were negative; therefore, there is no concern for genotoxicity.
