Experimental studies on carcinogenesis in the nasal mucosa.

Of 24 Syrian golden hamsters exposed to wood dust in a concentration in the air of 30 mg/m3 for 6 h per day, 5 days a week, for a period of 40 weeks, one animal got dysplasia and one a malignant tumour in the nasal mucosa. In a group of 24 animals given 3 mg of diethylnitrosamine subcutaneously once a week for 12 weeks, a high frequency of benign and malignant tumours (mainly adenocarcinoma) of the nasal mucosa was found, but a group of similar size exposed to both wood dust and diethylnitrosamine did not show a higher frequency of nasal tumours than those given this latter substance alone.