Chlorpyrifos-methyl is an organophosphate insecticide that induces 100, 100, 63, and 97.3% mortality of the adult stored-grain pests L. bostrychophila, L. decolor, L. entomophila, and L. paeta, respectively, when applied to grain at a dose of 10 mg/kg.1 It also reduces the number of live progeny produced by L. bostrychophila, L. decolor, L. entomophila, and L. paeta by 100, 100, 30.4, and 41.1%, respectively, when applied to grain at a dose of 2.5 mg/kg. Chlorpyrifos-methyl (3 μM) reduces outgrowth of axon-like processes in mouse N2a neuroblastoma cells.2 Administration of chlorpyrifos-methyl (4-100 mg/kg) to pregnant female mice decreases H19 gene methylation in sperm as well as decreases anogenital distance and increases thymus and epididymis weights and serum testosterone levels in male offspring.3 Formulations containing chlorpyrifos-methyl have been used to control stored-grain pest and mosquito populations.
1.Nayak, M.K., and Daglish, G.J.Combined treatments of spinosad and chlorpyrifos-methyl for management of resistant psocid pests (Psocoptera: Liposcelididae) of stored grainPest Manag. Sci.63(1)104-109(2007) 2.Sachana, M., Flaskos, J., and Hargreaves, A.J.Effects of chlorpyrifos and chlorpyrifos-methyl on the outgrowth of axon-like processes, tubulin, and GAP-43 in N2a CellsToxicol. Mech. Methods15(6)405-410(2005) 3.Shin, H.S., Seo, J.H., Jeong, S.H., et al.Effect on the H19 gene methylation of sperm and organs of offspring after chlorpyrifos-methyl exposure during organogenesis periodEnviron. Toxicol.30(12)1355-1363(2015)