One-generation reproductive toxicity study of 2-methylbutane in Sprague-Dawley rats.

This study investigated the potential reproductive toxicity of 2-methylbutane in a one-generation reproductive toxicity study using Sprague-Dawley rats. A total of 24 male and female rats per group were given 2-methylbutane by gavage at 0, 100, 300, and 1000 mg/kg/day. Males were dosed for 10 weeks prior to mating and during mating. Females were dosed from 2 weeks before mating to day 21 of lactation. At 1000 mg/kg/day, both genders exhibited an increase in adrenal gland weight, however, a decrease in body weight gain and food intake, an increase in kidney weight, and an increased incidence of histopathological changes of the kidney were also observed in male rats. No treatment-related effects of 2-methylbutane were found in relation to the reproductive capacity of parental animals or the pre- and post-natal development of the F1 generation. There were no treatment-related effects in either gender at ≤ 300 mg/kg/day. Under these experimental conditions, the no-observed-adverse-effect level of 2-methylbutane was 300 mg/kg/day for general toxicity and 1000 mg/kg/day for reproductive capacity and pup development in rats.