Summary
Introduction:
This text is a scientific journal article that presents the results of a study on the levels of tobacco-specific nitrosamines (TSNa) in Canadian cigarettes. The study also examines the relationship between TSNa levels and tar, nicotine, and carbon monoxide deliveries, as well as the effect of ventilation on TSNa concentrations. The study aims to provide information on the levels of harmful substances in Canadian cigarettes in order to inform regulatory measures.
Key Points:
* The study analyzed 25 brands of Canadian cigarettes for TSNa in tobacco and mainstream smoke, as well as nitrate in tobacco.
* Preformed N'-nitrosonornicotine (NNN) in the tobacco ranged from 265 ng to 979 ng/cigarette, and preformed 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) ranged from 465 ng to 878 ng/cigarette.
* The mainstream smoke concentration for NNN was between 5 ng and 39 ng/cigarette, and for NNK between 5 ng and 97 Ng/cigarette.
* The nitrate levels were between 0.3 mg and 3.4 mg/cigarette.
* The NNK levels in tobacco and in mainstream smoke were higher than the NNN levels, which is typical for Virginia-type cigarettes.
* Based on the average mainstream smoke concentration of the three most popular Canadian cigarette brands, an average TSNa delivery for 20 cigarettes of 0.7 pg NNN and 1.7 pg NNK can be calculated, which is less than the average for West German cigarettes.
* There seems to be a good correlation between the TSNa and tar deliveries in mainstream smoke, but no correlation between the level of preformed TSNa in tobacco and the tar delivery in mainstream smoke was observed.
* The ventilation ratio had a much higher influence on the mainstream smoke concentration than the level of preformed TSNa in tobacco.
Main Message:
The study demonstrates that TSNa levels in Canadian cigarettes vary widely, with NNK levels being higher than NNN levels in most brands. The study also highlights the correlation between TSNa and tar deliveries in mainstream smoke, but notes that this correlation can be attributed to the unusual good correlation between the tar delivery and the ventilation ratio. The findings suggest that efforts to reduce tar and nicotine in cigarettes through ventilation may also result in decreased TSNa concentrations. however, the study also emphasizes that further research is needed to fully understand the relationship between TSNa levels and cigarette design. Overall, the study provides valuable information for regulators seeking to reduce the harmful effects of cigarette smoking.
Citation
Fischer, Sophia, andre Castonguay, Murray Kaiserman, Bertold Spiegelhalder, and Rudolf Preussmann. “Tobacco-Specific Nitrosamines in Canadian Cigarettes.” Journal of Cancer Research and Clinical Oncology 116, no. 6 (November 1990): 563–68. https://doi.org/10.1007/BF01637075.
