We are interested in comparing the levels of harmful or potentially harmful constituents in Swedish and American smokeless tobacco products (STPs).
McAdam et al Chemistry Central Journal (2018) 12:86 https://doi.org/10.1186/s13065-018-0454-x RESEARCH ARTICLE Open Access Ethyl carbamate in Swedish and American smokeless tobacco products and some factors affecting its concentration K. McAdam1*, C. Vas1, H. Kimpton1, A. Faizi1, C. Liu1, A. Porter2, T. Synnerdahl3, P. Karlsson3 and B. Rodu4 Abstract Background: We are interested in comparing the levels of harmful or potentially harmful constituents in Swedish and American smokeless tobacco products (STPs) We report here the concentrations of the IARC Group A (probable human) carcinogen ethyl carbamate (EC) in seventy commercial STPs from the US and Sweden, representing 80–90% of the market share of the major STP categories in these countries We also examine the effects of various additives, processing and storage conditions on EC concentrations in experimental snus samples Results: EC was determined from aqueous extracts of the STPs using ultra performance liquid chromatography tandem mass spectrometry (UPLC/MS/MS) EC was undetectable ( 99.9%, Fisher Certified Analytical Reagent, Fisher Chemicals, P/N: S/3160/53) directly into a 40 ml plastic sterilin pot Deionised water (18.2 MΩ) was added using P10 and P5 ml air displacement Gilson pipettes, to give a 25 mM (1.461 mg/ml) solution A 2.5 mM intermediate standard solution was prepared by diluting the stock solution by a factor of 10 The instrument was calibrated using working standard solutions of sodium chloride (with concentrations of 10, 25, 50, 100, 250 and 500 µM), prepared from the sodium chloride stock or intermediate working standards by appropriate dilution The diluted extracts and calibration solutions were analysed with a Dionex ICS-3000 Ion Chromatography System The reporting limit equates to 0.92 mg/g WWB for sodium ions and 1.42 mg/g WWB for chloride ions Results Product survey Results for EC concentrations in the STP samples are shown, product-by-product, in Additional file 1: Tables McAdam et al Chemistry Central Journal (2018) 12:86 Page of 17 S1a and S1b, together with the other analytes measured in this study EC concentrations in commercial STPs The concentrations of EC were below the LOD (20 ng/g WWB) for all the CT, DS, HP, SP, and plug products In contrast, EC was detected in four of the ten L snus, 15 of the 22 P snus, and in 11 of the 16 MS products Averages by category of STP product (on a WWB) were calculated by assigning values of LOD/2 (i.e 10 ng/g) to samples that had levels of EC less than LOD [24] EC averages and ranges of concentrations (in ng/g WWB) were as follows: P snus 28.1 (range