Environmental exposure to trace elements and risk of cutaneous melanoma

Purpose: Our aim was to examine the risk of melanoma in association with exposure to trace elements of toxicological and nutritional interest. Methods: We analyzed the concentrations of cadmium, lead, chromium, selenium, copper and zinc in toenails of 58 patients with newly diagnosed cutaneous melanoma as well as in 58 age- and sex-matched control subjects, randomly selected from the population of Modena province in northern Italy. Results: Melanoma risk was substantially unrelated to toenail levels of cadmium, chromium, lead and selenium. Subjects with higher toenail copper levels showed an excess risk, both in the crude analysis and after adjusting for sun exposure and level of education, while in both analyses high iron concentrations were associated with a decreased risk of the disease. A weak direct association between zinc levels and melanoma risk also emerged in the multivariate analysis. Conclusions: Overall, these results do not suggest an involvement of heavy metals in melanoma etiology, while they do give some support to a possible role of zinc and, in particular, copper and iron exposure in influencing disease risk. However, these findings must be evaluated with caution due to the limited statistical stability of the point estimates.