Abstract
Male Syrian golden hamsters inhaled 0.5-1 ppm (= 2.7-5.5 mg/m3) of N-nitroso-N-acetoxy-methyl-N-methylamine 1 h/week, for 14 weeks. The total dose per animal was calculated as 150-400 micrograms or 1-3 mg/kg. Four squamous cell carcinomas and one mucoepidermoid carcinoma of the nasal mucosa were observed. No such tumors occurred in the control group.