Cadmium and nickel in mainstream particulates of cigarettes containing tobacco grown on a low‐cadmium soil‐sludge mixture

Cigarettes were prepared from tobaccos grown in the greenhouse on a soil to which a low rate of a municipal sewage sludge was applied. The cigarettes were smoked by machine and the mainstream particulate fraction was analyzed for total cadmium and nickel content. Sludge-grown and control (soil-grown) tobaccos contained, respectively, 5.33 and 1.87 ppm of cadmium and 1.15 and 0.64 ppm of nickel. The average quantities of cadmium and nickel (ng/cigarette) found in the mainstream particulate fractions were, respectively, 220.5 and 78.5 for the sludge-grown and 147.4 and 72.6 for the control treatments. The difference between treatments was highly significant (p less than 0.001) for cadmium but not significant for nickel.