Relationship between arsenic-containing drinking water and skin cancers in the arseniasis endemic areas in Taiwan

Artesian well‐water had high concentrations of arsenic that led to the well‐known black foot disease in Taiwan around the 1950s, and the associated cancers including skin cancer, bladder cancers and lung cancers. We sought to estimate the standardized morbidity ratio (SMR) and age‐standardized incidence rate (ASIR) of cutaneous squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) in the black foot disease endemic areas (BFDEA) in Taiwan. A nationwide retrospective population‐based survey was done with the data from the National Taiwan Cancer Registry Center between 1979 and 2007. Among the 29‐year period, there were 11 191 cases with SCC and 13 684 cases with BCC diagnosed pathologically. The incidence rates were 4–6‐fold higher for SCC and 3–4‐fold higher for BCC in the BFDEA compared with the rest of Taiwan. The SMR decreased after stopping arsenic‐containing well‐water drinking in the 1970s. The arsenic level in the drinking water, amount of contaminated water intake, occupation and sun‐exposure time were not documented. This is the first nationwide, population‐based study that shows the relationship between arsenic intoxication and non‐melanoma skin cancers (SCC and BCC) through comparing the data in people living in the BFDEA and non‐BFDEA in Taiwan.