Assessment of carcinogenic heavy metal levels in Brazilian cigarettes

Abstract

Several studies have associated high cancer incidence with smoking habits. According to IARC, lead (Pb), cadmium (Cd), arsenic (As), nickel (Ni), and chromium (Cr) are carcinogenic to humans. These metals are present in cigarettes and their levels vary according to geographical region of tobacco cultivation, fertilizer treatment, plant variety etc. This study aims to assess these metal levels in cigarettes commercialized in Brazil. Three cigarettes of each 20 different brands were individually weighed, the tobacco filling removed, and homogenized. After desiccation, samples were subjected to microwave-assisted digestion. Analyses were performed by graphite furnace atomic absorption spectrometry. Mean levels for Pb, Cd, As, Ni, and Cr were, respectively, 0.27 ± 0.054, 0.65 ± 0.091, 0.09 ± 0.024, 1.26 ± 0.449, and 1.43 ± 0.630, in micrograms per gram of tobacco. No correlation was observed between Cd and any other metal analyzed. A mild correlation (r = 0.483, p < 0.05) was observed between Pb and Cr levels. Strong significant (p < 0.01) correlations were observed between Ni and Cr (r = 0.829), Ni and As (r = 0.799), Ni and Pb (r = 0.637), and between Cr and As (r = 0.621). Chromium and Ni levels were significantly higher in cigarettes from a multinational manufacturer. Our results show a high variability in heavy metal levels in cigarettes, representing an important exposure source of smokers and passive smokers to carcinogenic substances.

Cadmium and nickel in blood of Tunisian population and risk of nasosinusal polyposis disease

“…PY (Pack-Year) smoking index expressed as the number of packs of 20 tobacco cigarettes per day for 1 year, SD standard deviation, ns non-significant (p>0.05) a Significantly different compared with the controls in the same stratum of risk factor group b All types of tobacco consumption (smoking+shisha+chewing) c The blood Cd and Ni levels increase significantly among controls and cases d Former smokers: subjects who smoke between 1 to 18 PY; current smokers: subjects who smoke more than 18 PY However, Collins et al (2002) and Wu et al (2013) found that nasal polyps appears to be affected by certain modifiable extrinsic factors, including cigarette smoking. Several studies reported that tobacco consumption constitutes an important source of chronic exposure to numerous xenobiotics, including heavy metals in particular Cd (IARC 1990;Wadhwa et al 2010;Viana et al 2011;Ashraf 2012). Previously, Cd and Ni exposure via tobacco consumption has been estimated based on the measurements of their concentrations in the blood of smokers compared to nonsmokers Gil et al 2011;Khlifi et al 2014b).…”

Cadmium exposure and tobacco consumption: Biomarkers and risk assessment

“…In certain smokeless tobacco (SLT) products, cadmium concentrations have been reported to range between 450 and 1880 ng per gram dry weight Maier et al, 1989;Pappas et al, 2008). In non-combusted cigarette tobacco, cadmium has been reported at concentrations between 100 and 4,950 ng per gram of tobacco (Viana et al, 2011;Westcott and Spincer, 1974;Yue, 1992). And in cigarette MSS, depending on cigarette design and the machine smoking regimen, cadmium concentrations between 1.6 and 222 ng per cigarette have been reported (Counts et al, 2005;IARC, 2004).…”

Impact of exposure to second-hand smoke on the levels of arsenic: data from NHANES 2003–2010

“…On the contrary, univariate analysis suggested that the levels of arsenic are statistically significantly higher in the absence of SHS exposure at home as compared to in the presence of SHS exposure at home (Table 2) for children and adults. These results, given the research findings that arsenic is present in cigarette smoke (Lazarevi c et al 2012, Viana, Garcia, andMenezes-Filho 2011), were totally unexpected. These results can, however, be explained by the racial/ethnic composition (Table 1) of those who had SHS exposure at home and those who did not.…”

“…Arsenic has been found to be a constituent in tobacco, the levels of which may vary by plant variety, geographical location of tobacco cultivation, and fertilizer treatment among other factors (Viana, Garcia, and Menezes-Filho 2011). In a study (Lazarevi c et al 2012) that evaluated the levels of arsenic and lead in 617 tobacco samples and 80 samples of cigarettes, the mean level of arsenic found in tobacco and cigarette samples was found to be 0.15 mg/g (<0.02À2.04 mg/g) and 0.11 mg/g (<0.02À0.71 mg/g), respectively.…”

“…Fresquez, Pappas, and Watson (2013) have reported levels of arsenic in tobacco from 50 varieties of cigarettes available in the US. In a study of 20 brands of cigarettes commercialized in Brazil, mean arsenic level was found to be 0.09 § 0.024 mg per cigarette (Viana, Garcia, and Menezes-Filho 2011). According to World Health Organization's (WHO) document (http://www.euro.who.int/__data/assets/pdf_file/0014/123071/AQG 2ndEd_6_1_Arsenic.PDF), arsenic content in mainstream cigarette smoke is in the range of 40À120 ng per cigarette and daily intake of arsenic for someone smoking 20 cigarettes a day is 0.8À2.4 mg (http://health.state.tn.us/Downloads/TVA_ArsenicFS.pdf).…”