This webpage is maintained by the Centers for Disease Control and Prevention (CDC). The webpage provides information and resources on Mercury. "Exposure to mercury occurs from breathing contaminated air, ingesting contaminated water and food, and having dental and medical treatments. Mercury, at high levels, may damage the brain, kidneys, and developing fetus. This chemical has been found in at least 714 of 1,467 National Priorities List sites identified by the Environmental Protection Agency."
Centers for Disease Control and Prevention: http://www.cdc.gov/