Embryotoxicity and fetotoxicity of inhaled or ingested vinylidene chloride in rats and rabbits.

The teratogenic potential of inhaled or ingested vinylidene chloride was evaluated in Sprague-Dawley rats and New Zealand white rabbits. Both species were exposed to the test material by inhalation for 7 hr/day at concentrations of 20 (rats only), 80, or 160 ppm. For the ingestion study, rats were given drinking water containing 200 ppm vinylidene chloride. Rats were given vinylidene chloride from the 6th to the 15th days of gestation and rabbits on the 6th to the 18th days. A teratogenic effect was not seen in rats or rabbits inhaling concentrations of up to 160 ppm vinylidene chloride for 7 hr/day or in rats given drinking water containing 200 ppm vinylidene chloride. Toxicity to both the dams and their developing embryos was observed among the rats inhaling 80 or 160 ppm and among the rabbits inhaling 160 ppm. At exposure levels which caused little or no maternal toxicity (20 ppm in rats and 80 ppm in rabbits), there was no effect on embryonal or fetal development. Among the rats given drinking water containing 200 ppm VDC, there was no evidence of toxicity to the dams or their offspring.