Late Inhalation Toxicology and Pathology Produced by Exposure to a Single Dose of 2-Chlorobenzylidene Malononitrile (CS) in Rats and Hamsters

Abstract

Hamsters and rats exposed to single doses of CS were retained for up to 32 months, together with appropriate controls. Survival was unaffected and in no case was the incidence of histological changes significantly higher in the test animals than corresponding control animals. The overall incidence of neoplastic disease was similar in test and control animals. A high incidence of pituitary acidophil adenomas was detected in the female rats: these tumours were present both in control and test rats and it was concluded that they were probably the result of ad libitum feeding. It was concluded that single doses of CS of 28 800 mg min m−3 administered during 1 hour or 18 000 mg min m−3 administered over 2 hours produced no long-term adverse effects in the two species studied.