The relation between urinary metabolite of pyrethroid insecticides and semen quality in humans

Objective: To explore the possible association between internal exposure levels of 3-phenoxybenzoic acid (3-PBA), an urinary metabolite of pyrethroids, and altered semen quality in Chinese men. Design: A retrospective case-control study. Setting: Center of clinical reproductive medicine. Patient(S): Three hundred seventy-six men with nonobstructive infertility. Main Outcome Measure(s): Urinary 3-PBA concentration, semen volume, sperm concentration, sperm number per ejaculum, sperm motility, sperm progression, and motion parameters. Result(S): The median 3-PBA concentration was 0.879 mu g/g of creatinine. There was suggestive association between increased creatinine-adjusted 3-PBA quartiles and sperm concentration (odd ratios for the first, second, third, and fourth quartiles were 1.00, 1.31, 1.73, and 2.04, respectively), whereas sperm volume, sperm number per ejaculum, and sperm motility were weakly or non significantly associated with 3-PBA quartiles. The sperm progression and motion parameters associated with creatinine-adjusted 3-PBA levels were straight line velocity (VSL) and curvilinear velocity (VCL). Conclusion(s): These observed associations between 3-PBA levels and some altered semen quality indicated the reproductive effects of pyrethroid exposure on adult men.