Around 2,000 water systems in all 50 states contain excessive levels of lead, according to a report by USA Today.
The water systems, which revealed lead levels exceeding Environmental Protection Agency (EPA) standards, collectively supply water to some 6 million people, the report found.
According to the USA Today analysis of EPA data, there were 600 water systems in which tests at some faucets indicated lead levels exceeding 40 parts per billion (ppb), which is more than double the EPA's stated limit.
Many of the highest reported lead levels were found at schools and day care centers.
The new report coincides with a congressional hearing on Thursday investigating the lead contamination crisis in Flint, Michigan. Both EPA Administrator Gina McCarthy along and Michigan Governor Rick Snyder are testifying.
"Let me be blunt," Snyder said in his opening statement to the House Committee on Oversight and Government Reform. "This was a failure of government at all levels. Local, state, and federal officials — we all failed the families of Flint."
EPA officials have denied responsibility, even though they failed to warn the public and demand remedial action as soon as they knew lead was leeching into the city’s water system.
This is the third hearing on the Flint water crisis.
Meanwhile, according to a new Gallup poll released Thursday, a majority U.S. citizens now worry "a great deal" about polluted drinking water (61 percent) and the pollution of rivers, lakes and reservoirs (56 percent).
These figures come as details surrounding the water crisis in Flint, Michigan, continue to emerge, the Gallup survey noted.
Polluted drinking water and the pollution of rivers, lakes and reservoirs have consistently topped Americans' concerns throughout Gallup's 27-year polling on environmental issues.
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