1,3-dichloropropene: two-generation inhalation reproduction study in Fischer 344 rats

This study evaluated the effects of inhaled technical-grade 1,3-dichloropropene (DCPT) on reproduction and neonatal growth and survival. Groups of 30 male and 30 female Fischer 344 rats, approximately 6 weeks of age, were exposed via inhalation to 0, 10, 30 or 90 ppm DCPT for 6 hr/day, 5 days/week, for two generations. The parental f0 and f1 generations were each bred twice. Reproductive and neonatal parameters evaluated included indices of fertility and pup survival, gestation length, litter size, pup body weight, and pup sex ratio. Gross and histologic examinations were concluded on all f0 and f1 adults. In addition, randomly selected f1b and f2b weanlings were given gross examinations. Parental effects were limited to rats exposed to 90 ppm DCPT and included decreased body weights and histopathologic effects on the nasal mucosa of adult male and female rats. The histopathologic effects consisted of slight, focal hyperplasia of the respiratory epithelium and/or focal degenerative changes in the olfactory epithelium. No adverse effects on reproductive parameters or neonatal growth or survival were observed in the f1a, f1b, f2a, or f2b litters even at an exposure concentration which produced effects in adult animals. Based on these results, it is concluded that inhalation exposure of rats up to 90 ppm DCPT for two successive generations did not adversely affect the reproductive and neonatal parameters evaluated.