Chronic arsenic exposure is linked with adverse health outcomes like increased risk for skin, liver and bladder cancers, skin lesions, cardiovascular disease etc.
During the research, it was 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 U.S, it is added to flour and other fortified foods.
The researchers found that folate deficiency is very common in Bangladesh but is not as problematic in the U.S. 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 U.S. Mary Gamble, Ph.D., a researcher at Columbia University and the lead author of the study said: "This is a very exciting and significant finding, and implies that folic acid has therapeutic potential for people who have been exposed to arsenic."
"Although additional studies are needed, the results of this study suggest that a simple, low-cost nutritional intervention may help to prevent some of the long-term health consequences associated with arsenic exposure for the many populations at risk.
"Folic acid supplementation enhanced the detoxification of arsenic to a form that is more readily excreted in urine," Gamble said.
She has explained 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.
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.
"The technology to measure arsenic in blood, and particularly to measure the individual arsenic metabolites in blood, didn't exist when the studies were first planned," Gamble said.
The authors also insisted 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.
The researchers added that additional studies are needed, for example, studies to determine the optimal dose and duration of treatment, and studies that include health outcomes. The study results are published in the October issue of the American Journal of Clinical Nutrition.