Inhalation teratology study on hexachloro-1,3-butadiene in rats

Abstract Pregnant rats were exposed to 0, 2, 5, 10 or 15 ppm hexachloro-1,3-butadiene (HCBD) 6 h/d during days 6–20 of gestation. Maternal reproduction and fetal parameters were evaluated on gestational day 21. A significant reduction in maternal weight gain and in fetal body weight occurrred at 15 ppm. The incidences of external, visceral and skeletal alterations were not significantly increased in any of the HCBD-exposed groups. It is concluded that exposure of pregnant rats to HCBD by inhalation at concentrations high enough to cause maternal and slight fetal toxicity is neither embryotoxic nor teratogenic.