Assessment of concentration and toxicological (Cancer) risk of lead, cadmium and chromium in tobacco products commonly available in Bangladesh

This study aimed to assess the concentrations of heavy metal (‘lead (Pb)’‘cadmium (Cd)’, and ‘chromium (Cr)’) in various brands of four types of tobacco products (zarda, gul, cigarettes, and bidi) as well as calculate toxicological risk as a lifetime cancer risk for Pb, Cd, and Cr. In smokeless tobacco products, the metal concentration ranged from 0.99 to 10.02 μg/g for Pb, 1.05–3.53 μg/g for Cd, and 1.23–7.29 μg/g for Cr, respectively. Metal concentrations in the smoke-based tobacco products ranged from 0.98 to 3.07 μg/g for Pb, 0.91–3.46 μg/g for Cd, 1.08–6.75 μg/g for Cr, respectively. When assuming a 100% transfer of these metals, the calculated lifetime cancer risk was found ‘unacceptable’ in 33 out of 35 tobacco samples which exceeded the U.S. Environmental Protection Agency (USEPA) benchmark of an ‘acceptable’ cancer risk range of 10E-4 to 10E-6. Our study demonstrated higher levels of Pb, Cd, and Cr in various tobacco products of Bangladesh compared to GOTHIATEK standard. This study shows the need for the development of industry standards and regulation for tobacco products to reduce the levels of heavy metals. Keywords: Heavy metals, Smoke-based and smokeless tobacco, Lifetime cancer risk, Banglades