For Immediate Release:
October 10, 2007 10 Oct 2007: Folic Acid Lowers Blood Arsenic Levels in BangladeshA new study conducted in Bangladesh finds that folic acid supplements can dramatically lower blood arsenic levels in individuals chronically exposed to arsenic-contaminated drinking water. Arsenic is a toxic element that is naturally present in some soils and water. Arsenic-contaminated drinking water is currently a significant public health problem in at least 70 countries, including several developing countries and also parts of the United States. Chronic arsenic exposure is associated with increased risk for skin, liver and bladder cancers, skin lesions, cardiovascular disease, and other adverse health outcomes. The study was funded by the National Institute of Environmental Health Sciences (NIEHS) at the National Institutes of Health (NIH). Researchers found that treatment with 400 micrograms a day of folic acid, the U.S. Recommended Dietary Allowance, reduced total blood arsenic levels in a Bangladesh study population by 14 percent. Folate is a B vitamin found in leafy vegetables, citrus fruits, beans, and whole grains. Folic acid can also be taken as a vitamin supplement, and in the United States, it is added to flour and other fortified foods. The researchers found that folate deficiency is very common in Bangladesh, where the study was conducted, but is not as problematic in the United States due to folate fortification. Additional studies are needed to determine if folic acid similarly lowers blood arsenic in populations where folate deficiency is less common, such as in the United States. William Suk, Ph.D., Acting Deputy Director of the NIEHS discussed the significance of this work in Bangladesh to the U.S. He explains that arsenic contamination of groundwater is one of the five most common inorganic compounds found at Superfund sites and is present at over 70 percent of the sites.
Gamble explains how this detoxification process is able to lower the levels of arsenic found in the blood. She explains how the folic acid increased the methylation or detoxification of arsenic in the body, allowing the body to change some of the more toxic metabolite, or methylarsonic (MMA) acid, to a form that could more easily be excreted from the body. Chronic arsenic exposure currently affects 100 million persons worldwide, including populations in Bangladesh. The arsenic levels in drinking water in some parts of Bangladesh reach as high as 100 times the World Health Organization and the US Environmental Protection Agency (EPA) guidelines, which set a limit of 10 micrograms per liter for arsenic in drinking water. The initial supplement study included 200 folate-deficient participants drawn from a larger cohort study in Bangladesh examining the adverse health effects of arsenic. Study participants received either a daily tablet of 400 micrograms per day of folic acid or a placebo for twelve weeks. The researchers collected blood and urine samples at the beginning and end of the study. Dr. Gamble pointed out that, “The work that our grantees are doing in Bangladesh is extraordinary,” said Claudia Thompson, Ph.D., acting director of the SBRP. The authors also stress that the study results imply that folic acid supplementation may help to reduce body stores of arsenic even after exposure has been eliminated. Elevated risk for adverse health outcomes persists for decades after exposure has ceased. Additional studies are needed, the researchers add, including, for example, studies to determine the optimal dose and duration of treatment, and studies that include health outcomes. The National Institute of Environmental Health Sciences (NIEHS), a component of the National Institutes of Health, supports research to understand the effects of the environment on human health. For more information on environmental health topics, please visit our website at http://www.niehs.nih.gov/ (http://www.niehs.nih.gov/). Superfund Basic Research Program (SBRP) is a network of university grants that are designed to seek solutions to the complex health and environmental issues associated with the nation's hazardous waste sites. The research conducted by the SBRP is a coordinated effort with the Environmental Protection Agency, which is the federal entity charged with cleaning up the worst hazardous waste sites in the country. The SBRP is federally funded and administered by the National Institute of Environmental Health Sciences, an institute of the National Institutes of Health. http://www.niehs.nih.gov/research/supported/sbrp/index.cfm (http://www.niehs.nih.gov/research/supported/sbrp/index.cfm). The SPRP will hold its 20th anniversary annual meeting, "20 Years of Success and a Vision for the Future," in Durham, North Carolina, December 3-5, 2007. Visit http://tools.niehs.nih.gov/sbrp/events/index.cfm?id=23 (http://tools.niehs.nih.gov/sbrp/events/index.cfm?id=23) for more information. The National Institutes of Health (NIH) — The Nation's Medical Research Agency — includes 27 Institutes and Centers and is a component of the U. S. Department of Health and Human Services. It is the primary federal agency for conducting and supporting basic, clinical, and translational medical research, and it investigates the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov (http://www.nih.gov) . Reference: Gamble MV, Liu X, Slavkovich V, Pilsner J, Ilievski V, Factor-Litvak P, Levy D, Alam S, Islam M, Parvez F, Ahsan H, Graziano J. Folic Acid Supplementation Lowers Blood Arsenic. Am J Clin Nutr 86:1202-1209 (2007). Supported by grants RO1 ES011601 and P42 ES10349 from the NIEHS. |
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