Analysis of 23 Polycyclic Aromatic Hydrocarbons in Smokeless Tobacco by Gas Chromatography−Mass Spectrometry

Abstract

Smokeless tobacco contains 28 known carcinogens and causes precancerous oral lesions and oral and pancreatic cancer. A recent study conducted by our research team identified 8 different polycyclic aromatic hydrocarbons (PAH) in U.S. moist snuff, encouraging further investigations of this group of toxicants and carcinogens in smokeless tobacco products. In this study, we developed a gas chromatography-mass spectrometry method that allows simultaneous analysis of 23 various PAH in smokeless tobacco after a simple two-step extraction and purification procedure. The method produced coefficients of variation under 10% for most PAH. The limits of quantitation for different PAH varied between 0.3 ng/g tobacco and 11 ng/g tobacco, starting with a 300-mg sample. The recovery of the stable isotope-labeled internal standards averaged 87%. The method was applied to analysis of 23 moist snuff samples that include various flavors of the most popular U.S. moist snuff brands, as well as 17 samples representing the currently marketed brands of spit-free tobacco pouches, a relatively new type of smokeless tobacco. The sum of all detected PAH in conventional moist snuff averaged 11.6 (± 3.7) µg/g dry weight, 20% of this amount being comprised by carcinogenic PAH. The levels of PAH in new spit-free tobacco products were much lower than those in moist snuff, the sum of all detected PAH averaging 1.3 (±0.28) µg/g dry weight. Our findings render PAH one of the most prevalent groups of carcinogens in smokeless tobacco, along with tobacco-specific nitrosamines. Urgent measures are required from the U.S. tobacco industry to modify manufacturing processes so that the levels of these toxicants and carcinogens in the U.S. moist snuff are greatly reduced.

Perceptions of relative risk of disease and addiction from cigarettes and snus.

“…The development of products with lower nitrosamine (Osterdahl, Jansson & Paccou, 2004) and polycyclic aromatic hydrocarbon (PAH) levels (Stepanov et al, 2010) also means that the factual risks are likely to be lower today than with the snus types used 20-30 years ago (Lee & Hamling, 2009). A group of EU-appointed experts performed a review of studies of the risk of harm to health from combustible and non-combustible tobacco, and concluded that snus was 70-90 per cent less harmful to users' health than smoking (The Scientific Committee on Emerging and Newly-Identified Health Risks (SCENIHR), 2008).…”

Contrasting Smokers' and Snus Users' Perceptions of Personal Tobacco Behavior in Norway

“…Even though snus is not a new product in the Norwegian market, the present type of snus is different from previous types. Because of the production and storage methods, the new Swedish snus has a lower level of tobacco specific nitrosamines and polycyclic aromatic hydrocarbon compared with other smokeless tobacco products, including those used in Scandinavia before 1990 (Borgerding, Bodnar, Curtin, & Swauger, 2012;Stepanov et al, 2009). …”

Polycyclic Aromatic Hydrocarbons in the Mainstream Smoke of Popular U.S. Cigarettes

“…PAHs are present in some unburned tobacco products, particularly those containing fire-cured tobacco varieties. 6–7 During fire curing, PAHs in combustion fumes generated by smoldering wood are deposited on the tobacco leaves. 8 …”