For Release: July 8, 2010
Steve Bjerklie, Communications Coordinator, Norris Cotton Cancer Center, at Steven.P.Bjerklie@Dartmouth.edu or 603-653-9056.
Arsenic study raises N.E. implications
Lebanon, N.H.—A new study published in the journal The Lancet, focusing on the mortality from arsenic contamination of drinking water in Bangladesh, raises potential implications for New England and other regions with low-level exposure to arsenic in drinking water. According to Margaret Karagas, PhD, a professor of epidemiology at Dartmouth Medical School (DMS) and co-director of the Cancer Epidemiology and Chemoprevention Program at Norris Cotton Cancer Center, the new research provides valuable data for establishing health and risk guidelines for low levels of arsenic concentration.
The prospective cohort research, called Health Effects of Arsenic Longitudinal Study (HEALS), found that residents of Bangladesh who regularly drink well water with arsenic concentrations as low as 10 micrograms per liter, or 10 parts per billion, face a potentially greater risk of death. The researchers say their data demonstrate that an estimated 21% of deaths from all causes and 24% of deaths linked to chronic diseases (including cancers) in Bangladesh could be attributed to drinking arsenic-contaminated well water at concentrations at or greater than 10 micrograms per liter.
The U.S. Environmental Protection Agency limit for arsenic contamination of drinking water is 10 micrograms per liter; according to the New Hampshire Department of Environmental Services, approximately 13% of the drinking-water wells in New Hampshire exceed the EPA limit for arsenic contamination.
Long-term arsenic exposure has been linked with a higher risk of cancers of the liver, kidney, bladder, and skin, vascular disease and other serious health problems. Drinking water contaminated with arsenic is a significant public health problem in at least 70 countries.
In a commentary published with the HEALS research in The Lancet, Karagas stated: "The beauty of the HEALS cohort is that it includes concentrations at the lower end of the dose-response curve and concentrations at the high end at which known health effects occur. Such data are rarely available, yet they are important for establishing rational guidelines... An estimated 20% of the world's population lacks access to safe drinking water. In 2010, we are reminded once again of the effect of the earth's drinking water supply on the human lifespan and the challenges of securing this scarce resource."
Karagas, also a member of the Dartmouth Toxic Metals Research program, is currently involved in several ongoing, arsenic-related studies in New England. Examples are available here and here.
Dartmouth-Hitchcock Norris Cotton Cancer Center combines advanced cancer research at DMS with patient-centered cancer care provided at Dartmouth-Hitchcock Medical Center (DHMC); at Dartmouth-Hitchcock regional locations in Manchester and Keene, NH, and St. Johnsbury, Vt.; and at 11 partner hospitals throughout New Hampshire and Vermont. It is one of 40 centers nationwide to have earned the National Cancer Institute (NCI) designation of Comprehensive Cancer Center.