Under the Dome

Study cites widespread tap water contamination

Chemically tainted tap water
Chemically tainted tap water Environmental Working Group

A new study by an environmental research organization finds a toxic compound contaminates water in every state, affecting more than 200 million people.

The Environmental Working Group is using the analysis of more than 60,000 tap water tests to spur the U.S. Environmental Protection Agency to move quickly to establish a national safety standard for the material, hexavalent chromium.

The study includes the controversy in North Carolina, where private well owners who live near coal ash storage ponds throughout the state are concerned about elevated levels of the compound. Duke Energy, which owns the ponds, points out that there has been no proof that the higher levels are the result of leaking coal ash ponds. It is a naturally occurring substance.

The controversy in North Carolina is over whether a health screening level of 0.07 parts per billion is appropriate, and how best to explain health risks to well owners and let them decide whether to live on bottled water provided by Duke Energy or continue drinking and cooking with their well water.

A clash between Gov. Pat McCrory’s administration and state scientists led to the resignation of the state epidemiologist, who quit in protest, and damaging testimony from other state employees that surfaced in depositions in a lawsuit.

According to the Environmental Working Group study: “The EPA tests show that water tested in 1,370 U.S. counties had an average level of chromium-6 exceeding California's non-binding public health goal — the amount posing no more than a one-in-a-million risk of cancer for people who drink it daily for 70 years. (By contrast, the state's legal limit represents a cancer risk of 500 per million.) Comparing the public health goal to levels of contamination found in the EPA tests, EWG estimates that if left untreated chromium-6 in tap water will cause more than 12,000 excess cases of cancer by the end of the century.”

The study includes an interactive map showing individual test results for every water utility in the country.

Craig Jarvis: 919-829-4576, @CraigJ_NandO

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