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Your Environment. Your Health.

Arsenic Exposure Declines after New EPA Regulations

Ana Navas-Acien, M.D., Ph.D., Joseph Graziano, Ph.D., Steven N. Chillrud, Ph.D., Anne E. Nigra
Columbia University
R01ES025216, R01ES021367, P30ES009089, P42ES010349, T32ES007322

NIEHS grantees reported that after the U.S. Environmental Protection Agency (EPA) lowered the limit for arsenic levels in drinking water, exposure to arsenic dropped significantly among people using public water systems in the U.S. Because arsenic exposure is associated with higher rates of several types of cancer, the researchers estimated that reduced exposure was equivalent to a reduction of 200 to 900 lung and bladder cancer cases or 50 cases of skin cancer per year. They observed no improvements in arsenic exposure rates among users of private wells, which are not federally regulated.

The study used data from 14,127 people in the National Health and Nutrition Examination Survey (NHANES) between 2003 and 2014. The researchers measured levels of dimethylarsinate, the primary metabolite of inorganic arsenic in humans. They examined data from before and after 2006, when EPA lowered the arsenic regulatory limit from 50 to 10 micrograms per liter of drinking water.

After adjusting for other sources of arsenic, such as diet and smoking, the analysis showed that arsenic levels decreased by 17 percent for public water users. Specifically, levels fell from 3.01 micrograms per liter for 2003-2004 to 2.49 micrograms per liter in 2013-2014.

Citation: Nigra AE, Sanchez TR, Nachman KE, Harvey DE, Chilled SN, Graziano JH, Navas-Acien A. 2017. The effect of the Environmental Protection Agency maximum contaminant level on arsenic exposure in the USA from 2003 to 2014: an analysis of the National Health and Nutrition Examination Survey (NHANES). Lancet Public Health; doi:10.1016/S2468-2667(17)30195-0 [Online 22 Oct. 2017].

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