title: The combined toxicity of dibutyl phthalate and benzo(a)pyrene on the reproductive system of male Sprague Dawley rats in vivo.
abstract: Our previous studies revealed more than 100 pollutants, most of which were endocrine disruptors (EDs) in two Chinese rivers, the Jialing and the Yangtze near Chongqing. Most EDs, such as dibutyl phthalate (DBP) and benzo(a)pyrene (BaP), are known to act individually as reproductive toxicants. However, little is known about the combined toxicity of DBP and BaP. In the current study, male Sprague Dawley rats were subchronically exposed to single doses of DBP (250 mg/kg), single doses of BaP (5 mg/kg) and combined doses of DBP and BaP. Significant adverse effects were observed on the reproductive system, including decreased sperm count, increased production of abnormal sperm, changes in serum testosterone levels and irregular arrangements of the seminiferous epithelium. Biochemical analyses showed that the activities of superoxide dismutase and glutathione peroxidase decreased after exposure to these EDs. Therefore, our data suggest that exposure to DBP and BaP, in either separate or combined doses, can affect the reproductive system of male rats adversely via oxidative stress-related mechanisms. No significant additive effect was observed after combined exposure. These results indicate that exposure to mixtures of EDs have unexpected and elusive effects. Our findings provide preliminary but important data for assessing water safety in China.
authors.affiliation: Laboratory of Reproductive Biology, Chongqing Medical University, Chongqing, PR China.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Chen
authors.forename: Hui
authors.initials: H
authors.lastname: An
authors.forename: Lin
authors.initials: L
authors.lastname: Ao
authors.forename: Lei
authors.initials: L
authors.lastname: Sun
authors.forename: Wenbin
authors.initials: W
authors.lastname: Liu
authors.forename: Ziyuan
authors.initials: Z
authors.lastname: Zhou
authors.forename: Yingxiong
authors.initials: Y
authors.lastname: Wang
authors.forename: Jia
authors.initials: J
authors.lastname: Cao
mesh_terms: D000818:Animals; D001564:Benzo(a)pyrene / Q000633:toxicity*; D003993:Dibutyl Phthalate / Q000633:toxicity*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012989:Soil Pollutants / Q000633:toxicity
chemical_list: D012989:Soil Pollutants; D003993:Dibutyl Phthalate; D001564:Benzo(a)pyrene