Reproduction and Fertility Studies with N-isopropylaniline (n-ipa) by Inhalation in Sprague-dawley Rats with Cover Letter dated 080588.

摘要

N-isopropylaniline (CAS # 768-52-5) was evaluated for effects on male fertility in groups of 20 male Sprague-Dawley rats exposed to mean analytical concentrations of 0, 5.2, 20.2, and 100 mg/cu m in air, 6 hours/day, 5 days/week for approximately 11 weeks. Each male was then sequentially cohabitated for 5 nights each with 2 unexposed females, which were sacrificed 2 weeks after copulation for evaluation of pregnancy status and implantation loss. Exposure of the males continued during the mating period and for an additional 2 weeks afterward (approximately 15 weeks total exposure). Treatment was not paternally toxic based upon mortality, clinical toxicity, or gross lesions. Male fertility was also comparable to that of controls, as were rates of copulation and precoital times in their untreated female partners. Examination of females mated to treated or untreated males revealed no pre- or post-implantation (resorptions) losses, or fetal mortality attributable to treatment. [Monsanto Co; Reproduction and Fertility Studies with N-isopropylaniline (N- IPA) by Inhalation in Sprague-Dawley Rats; 07/07/88; EPA Document No. 89-880000221; Fiche No. OTS0513418-2] N-isopropylaniline (CAS # 768-52-5) was evaluated for effects on female reproduction in groups of 25 female Sprague- Dawley rats exposed to mean analytical concentrations of 0, 5.2, 20, and 100 mg/cu m in air, 6 hours/day, 5 days/week for approximately 11 weeks. Each female was then cohabitated (1:1) nightly with an unexposed male, while exposures continued on 5 days/week. Upon confirmation of copulation, the exposure rate was increased to a 7 day/week schedule through gestation Day 20, after which the mated females were left untreated to deliver their pups. On lactation Day 4, all but 8 pups (4/sex) were culled from each litter to be weaned and necropsied on Day 21 for assessment of pup viability. Treatment was associated with no maternal toxicity based upon mortality, clinical symptoms, pre- and post-conception bodyweights, or gross lesions on necropsy. Among treated females, pregnancy rates (confirmed copulations, viable implantations) were slightly reduced relative to controls, the reductions statistically significant (p < 0.05) only in the low dose group. Terms of precoitus and gestation were comparable to controls, and the number of offspring and viable pups did not reflect a treatment-based relevance. The study authors reported a N-IPA NOEL (no observed effect level) of 20 mg/cu m for reproduction in female rats.