Tobacco smoke, carcinogenicity

A large number of polycyclic aromatic hydrocarbons are known Many have been synthesized m the laboratory and several of the others are products of com bustion Benzo[a]pyrene for example is present m tobacco smoke contaminates food cooked on barbecue grills and collects m the soot of chimneys Benzo[a]pyrene is a carcinogen (a cancer causing substance) It is converted m the liver to an epoxy diol that can induce mutations leading to the uncontrolled growth of certain cells... 

The number of clear human epidemiologic studies is small. A total of approximately 50 compounds (c.g., benzene, vinyl chloride) and complex e.xposures (e.g., aluminum production, tobacco smoke) have sufficient data available to permit their classification as human carcinogens. The most potent human carcinogens known, the aflatoxins. are of natural origin. Their presence in food products through infestation by toxin-producing fungi constitute a serious problem in several tropical and subtropical countries. 

Another example of enzyme induction involves CYP2E1, which is induced by consumption of ethanol. This is a matter for concern, because this P450 metabohzes certain widely used solvents and also components found in tobacco smoke, many of which are established carcinogens. Thus, if the activity of CYP2E1 is elevated by induction, this may increase the risk of carcinogenicity developing from exposure to such compounds. 

The involvement of tobacco smoke carcinogens in the aetiology of lung cancer is conclusively established, but the role of specific chemical carcinogens as inducers of colorectal cancer is much less clear. Mutagenic pyrolysis products derived from cooked food have come under suspicion as possible... 

Brunnemann, K.D. Hoffmann, D. Assessment of the Carcinogenic N-Nitrosodiethanolamine in Tobacco Products and Tobacco Smoke. Submitted. 

Polycyclic aromatic hydrocarbons (PAH) are widespread environmental contaminants and one of the most potent classes of carcinogenic chemicals. They are byproducts of combustion, and significant levels are produced in automobile exhaust, refuse burning, smoke stack effluents, and tobacco smoke. It is strongly suspected that PAH may play an important role in human cancer. 

Environmental tobacco smokes (ETS) tobacco smoke irritation to mucous membranes chronic and acutes pulmonary effects, cardiovascular effects carcinogenic. 

A method was developed to assess TSNA in indoor air polluted with tobacco smoke. Collection was followed by enrichment, concentration and desorption, and analysis by capillary GC-TEA. The concentration of A -nitrosonomicotine (299) was 0-23 pg/L, that of A -nitrosoanatabi nc (302) was 0-9 pg/L and that of 300 1-29 pg/L. Thus, nonsmokers can be exposed to highly carcinogenic TSNA616. 

IARC. 1986. IARC Monographs on the evaluation of the carcinogenic risk of chemicals to humans. Vol. 38. Tobacco smoking. International Agency for Research on Cancer, Lyon, France World Health Organization, 104-105. 

W. S. Schlotzhauer, M. E. Snook, O. T. Chortyk, and R. E. Wilson, Pyrolytic evaluation of low chlorogenic acid tobaccos in die formation of die tobacco smoke co-carcinogen catechol, J. Anal. 

One of the major toxicity issues in cannabis consumption relates to the fact that it is most often smoked. Cannabis and tobacco smoke, apart from having different psychoactive constituents, are actually very similar in their composition (Hoffman et ai. 1975). Cannabis smoke is mutagenic, which gives it carcinogenic potential (Nahas and Latour 1992). Although no specific reports of lung cancer or emphysema from cannabis smoke exist, it is at least as harmful as tobacco smoke, containing three times as much tar and five times as much carbon monoxide (Wu et al. 1988). Cannabis smoke inflames the airways and reduces respiratory capacity. Airway obstruction and squamous metaplasias may also occur. 

Kaiserman MJ, Rickeryt WS (1992) Carcinogens in tobacco smoke benzo[a]pyrene from Canadian cigarettes and cigarette tobacco. Am L Pub Health 82 1023-1026 Kozlowski LT, Mehta NY, Sweeney CT, Schwartz SS, Vogler GP, Jarvis MJ, West RJ (1998) Filter ventilation and nicotine content of tobacco of cigarettes from Canada, the United Kingdom, and the United States. Tob Control 7 369-375... 

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