Endorcine Effects of Pyrethroid Pesticide Esfenvalerate Metabolites; 3-Phenoxybenzyl Alcohol and 3-Phenoxybenzoic Acid
Much research has been conducted on type II pyrethroid pesticides but there is a paucity of research conducted on metabolites from these pesticides. 3-phenoxybenzoic acid and 3-phenoxybenzyl alcohol are two metabolites common to many of the type I and type II pyrethroid pesticides. In vitro experiments were conducted in our laboratory using MCF-7 estrogen dependent breast cancer cells. These cells were grown in 96 well plates and treated with 1mM, .1mM, .01mM, and .001mM concentrations of pyrethroid metabolites, 3-phenoxybenzoic acid and 3-phenoxybenzyl alcohol. Cell proliferation was measured and compared to cells grown in media only and media with 1nM estradiol. By day 10 the metabolite 3-phenoxybenzyl alcohol at a concentration of .001 mM showed proliferation, even larger than 1nM estradiol at incubation day 10 (2.69 nm versus 1.15 nm respectively). Metabolite 3-phenoxybenzoic acid at concentrations of .01 mM (.63 nm) and .001 (.56 nm) mM both also showed proliferation greater than 1nM (.54 nm) estradiol at day 5. In vivo experiments were conducted by dosing immature female Sprague Dawley rats with 10mg/kg esfenvalerate, 10mg/kg 3-phenoxybenzyl alcohol, and 10mg/kg, 5mg/kg, 1mg/kg 3-phenoxybenzoic acid. Vaginal opening (VO) was measured to indicate the onset of puberty. Previous data from our laboratory show that parent compound esfenvalerate delays puberty at a statistical significance of p< 0.05. Neither metabolite had any effect on the onset of puberty in our experiment.
Chavez, Marco (2009). Endorcine Effects of Pyrethroid Pesticide Esfenvalerate Metabolites; 3-Phenoxybenzyl Alcohol and 3-Phenoxybenzoic Acid. Available electronically from