“…These elements often include toxic heavy metals, especially arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni), and lead (Pb) (Mu et al, 2012;Passant et al, 2002). The carcinogenic potential of these heavy metals has been widely Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/envres studied in humans and experimental animals ('t Mannetje et al, 2011;Boffetta et al, 2011;Huang et al, 2004;Joseph, 2009;O'Brien et al, 2003;Oller, 2002;Verougstraete et al, 2003). The unifying factor in determining toxicity and carcinogenicity for all these metals is the generation of free radicals and oxidative stress, which can then cause oxidative damage to DNA and enhanced lipid peroxidation (Jeng et al, 2011;Valko et al, 2005).…”