Trace element status of some commercial smokeless tobaccos

Baseline conditions for sample handling, processing, chemical extraction, and chemical analysis of chewing tobacco were established. The chemical solubility patterns for cadmium, copper, nickel, selenium, and zinc in several commercial brands of chewing tobacco were determined. Five extractants were used: water with pH value of 3.0, pH value of 5.4, and pH value of 6.5; amylase (0.1%); and methanol (99.9%). The bulk of the total cadmium, copper, nickel, and zinc in the tobacco samples was in a tightly bound form not extracted to any appreciable degree by the solvents used. Selenium was below detectable limits for each of the extractants. It has been reported that copper and zinc may counter the carcinogenic effects of cadmium and nickel. The extractants solubilized a greater amount of copper and zinc than cadmium and nickel from the total metal present in the chewing tobacco.