In utero reproductive study in rats exposed to nonylphenol.
Alkylphenol ethoxylates are widely used non-ionic surfactants. Nonylphenol ethoxylate constitutes 82% of the production of all alkylphenol ethoxylates and the breakdown product of nonylphenol ethoxylate, nonylphenol (NP) has been shown to be estrogenic in both in vitro and in vivo screening assays. To determine the potential reproductive toxicity of NP, a one-generation in utero study was conducted. Rats were dosed from gestation day 11 through 18 with NP at 3, 15, or 75 mg/kg/day or diethylstilbestrol (DES) at 30 microg/kg/day. DES was used as a positive control. Both substances were given orally by gavage. Male offspring were sacrificed at postnatal day (PND) 11, 21, or 110 and reproductive parameters were evaluated. Pup birth weight and body weight and percent motile sperm at age of 110 day were significantly reduced by DES. The absolute weight of the right epididymis was significantly reduced in the DES group. The absolute weight of the right epididymis were also significantly decreased in the animals exposed to 75 or 15 mg/kg/day NP, effects which disappeared when organ weight was related to body weight. This study showed a dose-dependent effect of nonylphenol on male reproductive development at doses of 75 and 15 mg/kg bw/day based on absolute epididymal weight.
Hossaini
A
A
Institute of Food Safety and Toxicology, Danish Veterinary and Food Administration, Søborg. ALHO@lundbeck.com
Dalgaard
M
M
Vinggaard
A M
AM
Frandsen
H
H
Larsen
J J
JJ
D000818:Animals; D001724:Birth Weight / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D002624:Chemistry, Clinical; D004054:Diethylstilbestrol / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D004822:Epididymis / Q000187:drug effects / Q000473:pathology; D004968:Estrogens, Non-Steroidal / Q000633:toxicity*; D005260:Female; D005835:Genitalia / Q000187:drug effects; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D009929:Organ Size / Q000187:drug effects; D010636:Phenols / Q000633:toxicity*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D017208:Rats, Wistar; D012098:Reproduction / Q000187:drug effects*; D012741:Sexual Maturation / Q000187:drug effects; D013076:Sperm Count; D013081:Sperm Motility / Q000187:drug effects; D013501:Surface-Active Agents / Q000633:toxicity; D018675:Toxicity Tests
D004968:Estrogens, Non-Steroidal; D010636:Phenols; D013501:Surface-Active Agents; D004054:Diethylstilbestrol; C025256:nonylphenol; D007986:Luteinizing Hormone