Metal/metalloid levels and variation in lifetime cancer risks among tissues

Extreme variation in lifetime cancer risk among tissues has been a riddle of cancer etiology. Considering that cancer risks were found to be contributed heavily by environmental factors, levels of environmental carcinogens, such as metal/metalloid in tissues, may be an explanation of the variation. We analyzed the correlations between metal/metalloid concentrations in different tissues and the lifetime cumulative cancer risks of the corresponding tissues using the data of National Health Standards and National Central Cancer Registry of China. Cadmium (Cd) and rubidium (Rb) were found to be correlated with the lifetime cancer risks in a positive linear relationship while a U-shaped relationship was observed for cesium (Cs) and tin (Sn). A positive linear trend between the mixture of metals/metalloids and lifetime cancer risks was observed and cadmium (Cd) may be the main driving element. Our results indicated that Cd-based metal/metalloid levels may be an explanation for the variation in lifetime cancer risk among tissues. Furthermore, the analytical strategy may in turn help identify environmental factors involved in cancer etiology.