Normal Development of Reproductive System in Rat Male Offspring Following Perinatal Combined Exposure to p,p'-DDE and 1,4-Dichlorobenzene

摘要

Prenatal or early postnatal exposure to some synthetic chemicals may affect the later reproductive system of the offspring, and there may also be unique responses observed due to exposure to combinations of chemicals that are not observed when the chemicals are present individually. Organochlorine compounds are ubiquitously distributed in the environment. p,p'-DDE (l,l-dichloro-2,2 bis (p-chlorophenyl) ethylene) is a persistent metabolite of DDT and 1,4-dichlorobenzene (DCB) is used as an air freshener or a moth repellent. Oral p,p'-DDE intake through marine products and DCB concentrations of residential air are demonstrated to be high in Japan. Consequently, the fetus and neonate are supposed to be exposed much more to p,p'-DDE and DCB via the maternal body. Therefore, effects of perinatal combined exposure to p,p'-DDE and DCB on the male reproductive system after maturation have been investigated in rat male offspring of dams ingesting these contaminants during the perinatal period from gestational day 1 to postpartum day 21. In this study, no deteriorated developmental effects have been observed in rat male offspring until maturation following oral administration of 125 ppm p,p'-DDE (approximately 10 mg/kg) and 25 ppm DCB (approximately 2 mg/kg) to dams. Further, no obvious effects of perinatal combined exposure to DCB and p,p'-DDE on the male reproductive organs and sperm parameters were observed in mature male offspring.