title: Nasal cavity neoplasia in F344/N rats and (C57BL/6 x C3H)F1 mice inhaling propylene oxide for up to two years.
abstract: Propylene oxide (CAS: 75-56-9) was studied for potential carcinogenicity and chronic toxicity by inhalation in F344/N rats and (C57BL/6 x C3H)F1 mice. Groups of 50 animals of each sex were exposed to 0, 200, or 400 ppm propylene oxide for 6 hours/day, 5 days/week, for up to 103 weeks. Survival decreased in mice exposed to propylene oxide; the decrease was significant (P less than .005) in mice exposed to 400 ppm. Survival of exposed rats was comparable to that of controls. Mean body weight of rats and mice exposed to 400 ppm propylene oxide decreased, when compared to that of controls, during the 2d year of exposure. Exposure to propylene oxide for up to 2 years induced inflammatory and proliferative responses in nasal cavity of both species. There was clear evidence of carcinogenicity in mice exposed to 400 ppm propylene oxide; 10 of 50 males and 5 of 50 females had hemangiomas or hemangiosarcomas of the nasal submucosa. Papillary adenomas involving the nasal respiratory epithelium and underlying submucosal glands were observed in 3 female rats and 2 male rats exposed to 400 ppm propylene oxide.
authors.forename: R A
authors.initials: RA
authors.lastname: Renne
authors.forename: W E
authors.initials: WE
authors.lastname: Giddens
authors.forename: G A
authors.initials: GA
authors.lastname: Boorman
authors.forename: R
authors.initials: R
authors.lastname: Kovatch
authors.forename: J E
authors.initials: JE
authors.lastname: Haseman
authors.forename: W J
authors.initials: WJ
authors.lastname: Clarke
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D004852:Epoxy Compounds / Q000633:toxicity*; D004988:Ethers, Cyclic / Q000633:toxicity*; D005260:Female; D006391:Hemangioma / Q000139:chemically induced; D006394:Hemangiosarcoma / Q000139:chemically induced; D008297:Male; D051379:Mice; D009669:Nose Neoplasms / Q000139:chemically induced*; D010212:Papilloma / Q000139:chemically induced; D051381:Rats; D011916:Rats, Inbred F344; D012220:Rhinitis / Q000139:chemically induced; D013045:Species Specificity; D013997:Time Factors
chemical_list: D004852:Epoxy Compounds; D004988:Ethers, Cyclic; C009068:propylene oxide