Source: AACR Journals

Background Prevalence of tobacco use, both cigarette smoking and smokeless, including iqmik (homemade smokeless tobacco prepared with dried tobacco leaves mixed with alkaline ash), and tobacco-related cancer is high in Alaska Native people (AN). To investigate possible mechanisms of increased cancer risk we studied levels of nicotine and tobacco-specific nitrosamines (TSNA) in tobacco products and biomarkers of tobacco toxicant exposure in South Western AN people. Methods Participants included 163 cigarette smokers (CS), 76 commercial smokeless tobacco (ST), 20 iqmik, 31 dual CS and ST (DT) and 110 non-tobacco (NT) users. Tobacco use history, samples of tobacco products used and blood and urine samples were collected. Results Nicotine concentrations were highest in cigarette tobacco and TSNAs highest in commercial ST products. AN participants smoked on average 7.8 cigarettes per day (CPD). Nicotine exposure, assessed by several biomarker measures, was highest in iqmik users, and similar in ST and CS. TSNA exposure was highest in ST users, and polycyclic aromatic hydrocarbon exposure highest in CS. Conclusions Despite smoking fewer CPD, AN CS had similar daily intake of nicotine compared to the general US population. Nicotine exposure was greatest from iqmik, likely related to high pH due to preparation with ash suggesting high addiction potential compared to other ST products. TSNA exposure was much higher with ST compared to other product use, possibly contributing to high rates of oral cancer. Impact Our data help understanding high addiction risk of iqmik use and cancer-causing potential of various forms of tobacco use among AN people.

This news story was resourced by the Oral Cancer Foundation, and vetted for appropriateness and accuracy.