Toxicology and Carcinogenesis Studies of Commercial Grade 2,4 (80%)- and 2,6 (20%)- Toluene Diisocyanate (CAS NO. 26471-62-5) in F344/N Rats and B6C3F1 Mice (Gavage Studies)

摘要

Groups of 50 female F344/N rats and 50 female B6C3F1 mice were administered commercial grade toluene diisocyanate (80% 2,4- and 20% 2,6-) in corn oil by gavage at doses of 60 or 120 mg/kg body weight, 5 days per week for 105 or 106 weeks. Groups of 50 male F344/N rats received 30 or 60 mg/kg and groups of 50 male B6C3F1 mice received 120 or 240 mg/kg on the same schedule. Dosage analyses of toluene diisocyanate indicated that the chemical had reacted in the corn oil vehicle, resulting in actual gavage concentrations 77% to 90% of theoretical values. Groups of 50 rats and 50 mice of each sex received corn oil only and served as vehicle controls. Under the conditions of these gavage studies, commercial grade toluene diisocyanate in corn oil was carcinogenic for F344/N rats, causing subcutaneous fibromas and fibrosarcomas (combined) in males and females, pancreatic acinar cell adenomas in males, and pancreatic islet cell adenomas, neoplastic nodules of the liver, and mammary gland fibroadenomas in females. Toluene diisocyanate was not carcinogenic for male B6C3F1 mice. TDI was carcinogenic for female B6C3F1 mice, causing hemangiomas or hemangiosarcomas (combined), as well as hepatocellular adenomas.