title: Comparative carcinogenicity in F344 rats of the tobacco-specific nitrosamines, N'-nitrosonornicotine and 4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone.
abstract: The tobacco-specific carcinogens, N'-nitrosonornicotine (NNN) and 4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK), were tested for carcinogenicity in F344 rats. Each nitrosamine in trioctanoin was administered by s.c. injection to 12 male and 12 female rats over a period of 20 weeks. The total dose of each nitrosamine was 3.4 mmol. The experiment was terminated after 12 months. NNK induced nasal cavity tumors in 83% of the males and in 83% of the females, liver tumors in 83% of the males and in 100% of the females, and lung tumors in 67% of the males and in 67% of the females. NNN induced nasal cavity tumors in 92% of the males and in 75% of the females. Only one liver tumor and no lung tumors were observed in the NNN-treated rats. These results indicate that, in the F344 rat, NNK is a more powerful carcinogen than is NNN.
mesh_terms: D000818:Animals; D002273:Carcinogens; D005260:Female; D008113:Liver Neoplasms / Q000139:chemically induced; D008175:Lung Neoplasms / Q000139:chemically induced; D008297:Male; D009296:Nasal Cavity; D009374:Neoplasms, Experimental / Q000139:chemically induced* / Q000473:pathology; D009538:Nicotine / Q000031:analogs & derivatives* / Q000633:toxicity; D009602:Nitrosamines / Q000633:toxicity*; D009669:Nose Neoplasms / Q000139:chemically induced; D010947:Plants, Toxic; D011725:Pyridines / Q000633:toxicity; D051381:Rats; D011916:Rats, Inbred F344; D014026:Nicotiana
chemical_list: D002273:Carcinogens; D009602:Nitrosamines; D011725:Pyridines; D009538:Nicotine; C016583:4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone; C008655:N'-nitrosonornicotine