Arsenic exposure appears to continue causing lung and bladder cancer deaths years after exposure ends, according to a study published online June 12 in the Journal of the National Cancer Institute. Arsenic is a known cause of lung and bladder cancer, but researchers don’t yet know how long cancer risk remains elevated after arsenic exposure. The drinking water in a region of northern Chile became contaminated with very high amounts of arsenic beginning in 1958. In the 1970s, construction of water treatment plants in the region led to a decline in arsenic concentration. This sudden rise and fall of arsenic levels gave researchers the opportunity to investigate the period between first and last exposure to high levels of arsenic and subsequent mortality due arsenic-related cancers, such as bladder and lung cancer.
