LETHAL DOSE AND REPRODUCTIVE PARAMETERS OFp-NONYLPHENOL IN RATS

Abstract

Male reproductive abnormalities may be due to an increased level of maternal estrogens affecting the developing fetus. Man is exposed to environmental estrogens in multiple ways: diet, drinking water, air, and skin, para-Nonylphenol (p-NP), an alkylphenol, has estrogenic properties. This study was performed to evaluate the potency and workable concentrations before reproductive tests could be performed. The oral LD50 (median lethal dose) value for rats was 1475 mg/kg. For both males in the reproductive test the litter size after long-term treatment at 50 mg/kg p-NP was smaller than that in the breeding records. Five females did not conceive at all.

Antagonistic Effects of a Mixture of Low-Dose Nonylphenol and Di-N-Butyl Phthalate (Monobutyl Phthalate) on the Sertoli Cells and Serum Reproductive Hormones in Prepubertal Male Rats In Vitro and In Vivo

“…Animals were gavaged daily during the prepubertal stage from GD 23 to GD 35 with NP (50, 150, and 450 mg/kg/day), DBP (50, 150, and 450 mg/kg/day), and a combination of NP and DBP (50+50, 150+150, 450+450 mg/kg/day) dissolved in laboratory-grade corn oil at a volume corresponding to 5 mL/kg bw. A previous study demonstrated that the lethal dose 50 (LD50) of NP for rat was 1475 mg/kg [22] and an oral dose of 500 mg/kg/day of DBP to the rat dam during GD14–18 would be approximately half of the total effective dose which produces a 50% incidence (ED 50 ) of epididymal agenesis [23]. Therefore the highest concentration was 450 mg/kg/day for NP and DBP, respectively, and the dose of NP vs. DBP in the mixture was also at a fixed ratio.…”