摘要：

Fifty male inbred Syrian hamsters, aged 60–90 days, received a diet reduced in caloric content by 20% methylcellulose, or a diet containing 20% snuff (powdered tobacco), or 50 (5 mg) gavages of 20-methylcholanthrene (MC) in addition to chow, or 50 (0.5 mg) gavages of MC (assumed to be a noncarcinogenic dose) with a cellulose-containing diet, or 50 (0.5 mg) gavages of MC with a diet containing 20% snuff. These chronic feeding studies failed to reveal any carcinogenic or cocarcinogenic effects of snuff. Presence in serum of cotinine derived from nicotine, together with food consumption and body weight studies, showed adequate snuff intake. Tumors in the MC-fed animals demonstrated the susceptibility of the two inbred lines of Syrian hamsters used in this study. The only effect of snuff noted was a slower growth of the animals in one of the inbred lines but not in the other. The conclusion is warranted that 20% snuff in the diet is neither carcinogenic nor cocarcinogenic for these animals.

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