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Chemical Carcinogenesis and Mutagenesis
Published in Frank A. Barile, Barile’s Clinical Toxicology, 2019
Of the various environmental hazardous compounds, cigarette smoke enjoys the highest causal relationship with cancer risk in humans. Tobacco smoking plays a major role in the etiology of lung, oral cavity, and esophageal cancers as well as a variety of chronic degenerative diseases. Although cigarette smoke is a mixture of about 4000 chemicals, including more than 60 known human carcinogens, 4-methylnitrosamino-1-(3-pyridyl)-1-butanone (nicotine-derived nitrosamino ketone [NNK]) is the most carcinogenic tobacco-specific nitrosamine. NNK induces lung tumors in mice, rats, and hamsters, and the International Agency for Research on Cancer has designated NNK and NNN (N-nitrosonornicotine) as known human carcinogens. NNK is metabolically activated by CYP P-450 enzymes in the lung and generates O6-methylguanine in DNA. The reaction generates G:C to A:T mutations, with the subsequent activation of K-Ras proto-oncogene and the development of tumor initiation.
Nasal Cavity Carcinogens: Possible Routes of Metabolic Activation
Published in D. V. M. Gerd Reznik, Sherman F. Stinson, Nasal Tumors in Animals and Man, 2017
Stephen S. Hecht, Andre Castonguay, Dietrich Hoffmann
N′-Nitrosonornicotine (NNN) (see Figure 4) and 4-(methylnitrosamino)-l-(3-pyridyl)-l-butanone (NNK (1), Figure 5) are tobacco-specific nitrosamines which were detected in μg amounts in chewing tobacco and in main- and sidestream smoke of cigarettes and cigars.60-62 Of all the known N-nitrosamines found in the respiratory environment, tobacco-specific nitrosamines are the most prevalent.
Study on the daily Ad Libitum smoking habits of active Korean smokers and their effect on urinary smoking exposure and impact biomarkers
Published in Biomarkers, 2021
Jiyeon Yang, Shervin Hashemi, Wonseok Han, Chaelin Lee, Yoojin Song, Youngwook Lim
Another limitation of this study concerned the analysis of the urine NNAL. The disadvantage of this biomarker is that its level is significantly lower than that of the urinary cotinine, which makes it technically challenging. In this study, the urinary NNAL of 34% of the smokers was below the PQL, and therefore, was considered not detected (Schick et al.2017). During 2015–2016, the Ministry of Food and Drug Safety of the Republic of Korea gathered 400 packs of five cigarette products from 20 tobacco stores in seven regions across the country at different time and season intervals, and investigated the amount of 45 ingredients per cigarette, including tobacco-specific nitrosamines (TSNAs), in that their exposure can result in the appearance of the biomarker NNAL by using methods recommended by the International Organisation for Standardisation (ISO) and Health Canada (HC) (Ministry of Food and Drug Safety 2017). According to the results, the amount of N-nitrosonornicotine (NNN), nicotine-derived nitrosamine ketone (NNK), N-nitrosoanabasine (NAB), and N-nitrosoanatabine (NAT) per cigarette were not quantitative. This fact may also explain the relatively lower level of measured urinary NNAL in our samples compared to other studies (Counts et al.2004, Benowitz et al.2018). Accordingly, uncertain variables, such as quality of tobacco, harvesting condition and time, or processing of the leaves, can affect the composition of cigarettes, which could not be controlled in our study (Counts et al.2004, Morgan et al.2017).
Comparison of the content of tobacco alkaloids and tobacco-specific nitrosamines in ‘heat-not-burn’ tobacco products before and after aerosol generation
Published in Inhalation Toxicology, 2018
Won Tae Jeong, Hyun Ki Cho, Hyung Ryeol Lee, Ki Hoon Song, Heung Bin Lim
When cigarettes are burned, more than 4800 compounds are produced and released, of which 69 have been reported to be carcinogens (Hoffmann et al., 2001). In contrast to other components of smoke, nicotine and nitrosamines are inherent components of tobacco present both in tobacco products and in the smoke and they are of clear relevance to human health as they are considered to be harmful substances (Hecht, 1998; Mayer, 2014). Nicotine is a tobacco alkaloid (TA) and related compounds such as nornicotine, anatabine, anabasine, cotinine, and myosmine are typically also present and they are highly addictive to humans (Kataoka et al., 2009). Nitrosamines were first reported in the 1970s, and 35 different entities have been reported so far, with more than 8 entities present in tobacco and the smoke (Nestor et al., 2014). Among them, nitrosamines produced by nitrosation of nicotine, nornicotine, anatavine, and anabasine in tobacco are referred to as TSNAs, and N′-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-bipyridyl)-1-butanone (NNK), N′-nitrosoanatabine (NAT), and N′-nitrosoanabasine (NAB) are common in addition to being highly carcinogenic (Humans, 2007). Of note, it has been reported that TSNAs are not present in tobacco leaves when they are harvested in the field but are produced during the curing process (Fisher et al., 2012), and they are released into the smoke by distillation, pyrorelease, and pyrosynthesis when the tobacco product is smoked (Moldoveanu et al., 2008; Jaccard et al., 2018). As these entities are of clear relevance to the health of smokers, they are included as toxic substances for priority step-by-step monitoring as specified by the World Health Organization Framework Convention on Tobacco Control (WHO FCTC) (Hoffmann et al., 2001).
Association between biomarkers of tobacco consumption and lung cancer risk among daily smokers
Published in Expert Review of Respiratory Medicine, 2022
Adrián González-Marrón, Juan Carlos Martín-Sánchez, Raúl Pérez-Ortuño, Marcela Fu, Montse Ballbè, Àurea Cartanyà-Hueso, Nuria Matilla-Santander, José Antonio Pascual, Esteve Fernández, Jose M Martínez-Sánchez
Around 80% of the cases of lung cancer in the population are attributable to tobacco consumption [7]. Tobacco smoke contains a plethora of potentially harmful substances, including tobacco specific N-nitrosamines (TSNAs), which have been quantified to assess both active and passive smoke exposure, along with cotinine and other subproducts [8]. Many TSNAs, including 4-(methylnitrosamine)-1-(3-pyridyl)-1-butanone (NNK) and its metabolite 4-(methylnitrosamine)-1-(3-pyridyl)-1-butanol (NNAL), or N’-Nitrosonornicotine (NNN), are identified as carcinogens for humans [9]. Specifically, NNK and NNAL are promoters of lung cancer [10].