Characterisation and Health Risk Assessment of Selected Trace Metals in Different Brands of Cigarette Tobacco

Abstract

Cigarette tobacco is associated with numerous health effects which are mainly . associated with its chemical composition. The aim of the present study was to evaluate the levels of selected trace metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) and to study their comparative distribution, source apportionment and associated health risks in cigarette tobacco samples (n = 60) collected from the local markets of Rawalpindi and Islamabad, Pakistan. The cigarette tobacco samples were digested in HN03 and HCl04 (9:4) mixture. The levels of selected trace metals were quantified by flame atomic absorption spectrophotometry. The analytical data were evaluated by applying various statistical methods including univariate, bivariate, and multivariate analyses. Comparative assessment ofthe metal levels revealed highest mean concentration of Fe (162.4 flg/g), while the lowest mean concentration was found for Cd (1.252 flg/g) in the cigarette tobacco samples. Multivariate principal component analysis (PCA) and cluster analysis (CA) of the trace metal levels indicated significant anthropogenic contamination of the cigarette tobacco samples. Average levels of Fe, Co, Cu & Cd were comparatively higher in the local brands than the imported brands which showed elevated levels of Mn, Cr, Ni, Pb and Zn. Comparative assessment of the average metal levels based on origin, brands, varieties, and manufacturing companies revealed significant and random variations. Potential health risk assessment revealed significant risks as calculated in terms of estimated daily dose/intake ofthe metals through inhalation. The non-carcinogenic risk indicated significant risk for Co while carcinogenic risk showed significant cancer risk for Co, Ni and Cr levels in the cigarette tobacco samples. The comparative study demonstrated that the average levels of trace metals in the cigarette tobacco samples were higher than most of the literature reported levels from various regions around the world.