Changing Course On Perchlorate

The Environmental Protection Agency will set a national limit for the amount of perchlorate—a component of rocket fuel—and of several volatile organic compounds allowed in drinking water, agency Administrator Lisa P. Jackson announced last week.

EPA’s decision on perchlorate reverses a policy of the George W. Bush Administration not to regulate it. The substance is used in solid rocket fuel, flares, and fireworks, and it occurs naturally in some areas.

The conclusion to regulate perchlorate is “based on extensive review of the best available science and the health needs of the American people,” Jackson said.

Perchlorate interferes with thyroid metabolism. This can cause damage to the developing nervous systems of babies and young children. Between 5 million and 17 million Americans across 26 states may be exposed to perchlorate in their drinking water, according to EPA.

A national drinking water standard for the chemical may lead to sizable cleanup liability for the Defense Department, NASA, and the Department of Energy, whose operations have contaminated aquifers with perchlorate. Over the past decade, these agencies have vigorously opposed EPA regulation of this chemical.

In addition to its plan for perchlorate, EPA said it will set a separate drinking water standard for an assortment of volatile organic compounds that may cause cancer. This single regulation will cover trichloroethylene, perchloroethylene, and up to 14 other compounds that follow the same biochemical pathway in the body, Jackson told the Senate Environment & Public Works Committee at a Feb. 2 hearing.

Jackson last year ordered EPA regulators to address drinking water contaminants as groups rather than individually. Her goal is to provide health protections faster and allow water utilities to meet federal standards more efficiently.

Meanwhile, EPA is likely to regulate hexavalent chromium in drinking water, Jackson told the Senate panel. This form of chromium has long been known to cause cancer in humans when inhaled. A recent National Toxicology Program study on laboratory rodents indicates that Cr6+ can also lead to cancer when ingested in drinking water.

EPA will take at least two years to propose a standard for Cr6+ and almost two years more to finalize it, Jackson said at the hearing.