Smokeless tobacco products

Some chemical mixtures Tobacco smoke Smokeless tobacco products Soots, tars, mineral oils ... 

Smokeless tobacco products are a major form of tobacco addiction in several countries, notably India and South Africa. The tobacco may be chewed, sucked, or applied to the teeth or gums. The products may be manufactured commercially or at home. 

Ayo-Yusuf OA, Swart TJP, Hckworth WB (2004) Nicotine delivery capabilities of smokeless tobacco products and imphcations for control of tobacco dependence in South Africa. Tob Control 13 186-189... 

Since the late 1980s, there has been a proliferation of new potential reduced-exposure products (PREPs), promoted by the industry with the claims of reduced harm, in all the four categories that were summarized earlier (Stratton et al. 2001 Hatsukami et al. 2002, 2005). These include (a) modified tobacco products, such as several denicotinized brands and reduced TSNA emission cigarettes (b) chewing gum impregnated with tobacco (c) smokeless tobacco products with claimed reduced nitrosamine levels and (d) cigarette-like products (carbon-heated smoking devices). 

Henningfield JE, Radzius A, Cone EJ (1995) Estimation of available nicotine content in six smokeless tobacco products. Tob Control 4 57-61... 

Abstract Delivery of nicotine in the most desirable form is critical in maintaining people s use of tobacco products. Interpretation of results by tobacco industry scientists, studies that measure free-base nicotine directly in tobacco smoke, and the variability of free-base nicotine in smokeless tobacco products all indicate that the form of nicotine delivered to the tobacco user, in addition to the total amount, is an important factor in whether people continue to use the product following their initial exposure. The physiological impact of nicotine varies with the fraction that is in the free-base form and this leads to continued exposure to other toxic tobacco contents... 

The acid-base chemistry of nicotine is now well known and investigations have shown that nicotine in tobacco smoke or in smokeless tobacco prodncts can exist in pH-dependent protonated or nnprotonated free-base forms. In tobacco smoke, only the free-base form can volatilize readily from the smoke particnlate matter to the gas phase, with rapid deposition in the respiratory tract. Using volatility-based analytical measurements, the fraction of nicotine present as the free-base form can be quantitatively determined. For smokeless tobacco products, the situation differs because the tobacco is placed directly in the oral cavity. Hence, the pH of smokeless tobacco prodncts can be measured directly to yield information on the fraction of nicotine available in the nnprotonated free-base form. It is important to characterize the fraction of total nicotine in its conjugate acid-base states as this dramatically affects nicotine bioavailability, because the protonated form is hydrophilic while the nnprotonated free-base form is lipophilic and thus readily diffuses across membranes (Armitage and Turner 1970 Schievelbein et al. 1973). As drug delivery rate and addiction potential are linked (Henningfield and Keenan 1993), increases in delivery rate due to increased free-base levels affect the addiction potential. 

Table 1 Values of pH and levels of free nicotine in smokeless tobacco products...

Evidence from the tobacco industry documents, from research studies that measure free-base directly in tobacco smoke particulate, and from examination of smokeless tobacco products, all show that the level of free-base nicotine as delivered to the tobacco user is a critical variable in the acceptance of tobacco products and their continued use. The physiological impact of the rapid delivery of nicotine in the free-base form is a critical determinant of continued nicotine-seeking behavior, with the unintended consequences of exposure to the other toxic components of tobacco smoke and smokeless tobacco. Evaluating total delivered nicotine alone is not sufficient to characterize product differences. To fully understand the influence nicotine has on the allure of these products, both total and free-nicotine levels must be measured. A comprehensive understanding of nicotine delivery is needed to help find effective means for breaking its addictive nature and, ultimately, in reducing the morbidity and mortality associated with tobacco use. The levels of free-base nicotine must be included as part of any effort to achieve a better understanding of how tobacco products themselves influence their continued use. 

CDC (Centers for Disease Control and Prevention) (1999a) Annual submission of the quantity of nicotine contained in smokeless tobacco products manufactured, imported, or packaged in the United States requirement notice. Federal Register 64 14086-14096 CDC (Centers for Disease Control and Prevention) (1999b) Determination of nicotine, pH, and moisture content of six commercial moist snuff products - Florida, January-February 1999, Morb Mortal Wkly Rep 48 398 01... 

PhUip Morris et al. (1998) Comments before the Massachusetts Department of Public Health on proposed amendments to regulations entitled cigarette and smokeless tobacco products Reports of added constituents and nicotine ratings. October 2 1998. Massachusetts Department of Public Health. Boston, Massachusetts... 

As shown in Fig. 1, the speed of nicotine uptake in venous blood following several forms of nicotine delivery varies widely, from that of the very slow pattern of nicotine appearance in the blood (several hours to peak level) produced by current transdermal nicotine medications to the explosive rise produced by tobacco smoke inhalation. Nicotine gum, lozenge, tablet, and vapor inhaler can provide more rapid delivery of nicotine than the patch, but the speed and amount obtained are constrained by use patterns. Smokeless tobacco products deliver their nicotine more rapidly than nicotine gum and with less physical effort, but are still slower than cigarettes in their nicotine dehvery. 

Food and Drug Administration (1995) Regulations restricting the sale and distribution of cigarettes and smokeless tobacco products to protect children and adolescents proposed rule analysis regarding FDA s jurisdiction over nicotine-containing cigarettes and smokeless tobacco products notice. Fed Reg 60 41314 1792... 

A-Nitrosodiethanolamine has been detected in cigarette smoke at concentrations of 24-36 ng per cigarette, in smoking tobacco at concentrations up to 420 pg/kg, and in smokeless tobacco products (chewing tobacco, snuff) at concentrations up to 6800 pg/kg (Bruimemann Hoffrnaim, 1981 Bmnnemann et ah, 1982-1983 lARC, 1985). The presence of /V-nitrosodiethanolamine in tobacco and tobacco smoke was attributed, at least in part, to a maleic hydrazide-diethanolamine herbicidal combination commonly applied to tobacco to prevent sucker growth and levels of 7V-nitrosodiethanolamine have declined (< 100 ppb) in some tobaccos since the herbicide was phased out (Brunnemann Hoffmaim, 1991)... 

Tobacco habits other than smoking see Tobacco products, smokeless) Tobacco products, smokeless... 

The various smokeless tobacco products are described below ... 

The use of smokeless tobacco products among youths is a concern. The disparity in prevalence between men and women is extremely large. 

F The discrepancy is about 19-fold men use smokeless tobacco products far more than women do. 

Andersen, R.A., H.R. Burton, P.D. Eleming, and T.R. Hamilton-Kemp Effect of storage conditions on nitro-sated, acylated, and oxidized pyridine alkaloid derivatives in smokeless tobacco products Cancer Res. 49 (1989) 5895-5900. 

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