MANHATTAN (CN) - More than 16 million Americans' drinking water is contaminated by perchlorate, a byproduct of the defense and aerospace industries that can cause thyroid damage, and the U.S. refuses to regulate it, environmentalists claim in court.
The Natural Resources Defense Council's federal complaint accuses the U.S. Environmental Protection Agency of violating the Safe Water Drinking Act.
The EPA determined five years ago that perchlorate posed "a threat to human health that could meaningfully be reduced by regulating its presence in public drinking water," the Feb. 18 complaint states. Under the Safe Water Drinking Act, that gave the EPA a "mandatory duty" to propose and publish a regulation, within 24 months of its Feb. 11, 2011, determination.
According to the EPA's 2014 Technical Fact Sheet for perchlorate, 90 percent of the highly soluble chemical is manufactured for the defense and aerospace industries, mostly in the form of ammonium perchlorate.
The Department of Defense detected perchlorate at 284 installations - 70 percent of those sampled - including missile ranges and missile and rocket manufacturing facilities, according to the complaint.
Perchlorate is also found in some Chilean fertilizers.
Perchlorate can disrupt thyroid hormone production by impairing the uptake of iodine into the thyroid gland. As many at 16.6 million Americans get their drinking water from public water systems where perchlorate has been detected, according to the complaint.
The EPA had a mandatory duty to propose perchlorate regulations no later than Feb. 11, 2013, and to have finalized those regulations by Aug. 11, 2014 - so it's a year and a half overdue, the NRDC says.
It seeks an injunction "compelling EPA to propose a maximum contaminant level goal and a national primary drinking water regulation for perchlorate by a court-ordered deadline."
When the EPA does publish its regulation, the NRDC wants it members to be notified whenever perchlorate is detected in their drinking water supplies at unsafe levels, and what level of perchlorate has been detected.
Congress passed the Safe Drinking Water Act in 1974. It requires the EPA to publish "contaminant candidate lists" every five years, listing "contaminants that are not already subject to regulation, but that nonetheless are known or anticipated to occur in public water systems."
The NRDC is represented by house attorney Nancy Marks.
Representatives of the Department of Justice on behalf of the Environmental Protection Agency declined to comment.
The NRDC also is a co-plaintiff in a separate Safe Drinking Water Act lawsuit against Michigan, springing from the Flint drinking water fiasco.
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