Increased lung and bladder cancer incidence in adults after in utero and early-life arsenic exposure.

Background: From 1958 to 1970, >100,000 people in northern Chile were exposed to a well-documented, distinct period of high drinking water arsenic concentrations. We previously reported ecological evidence suggesting that early-life exposure in this population resulted in increased mortality in adults from several outcomes, including lung and bladder cancer.

Methods: We have now completed the first study ever assessing incident cancer cases after early-life arsenic exposure, and the first study on this topic with individual participant exposure and confounding factor data.