U.S. EPA announced today that it will reverse a George W. Bush-era stance and consider setting new federal drinking water standards for the rocket fuel component perchlorate, linked to thyroid problems and other developmental impediments.
The agency determined today that perchlorate presents a public health threat, saying that a proposal is on the way. An August study by the Government Accountability Office found the chemical -- which occurs naturally as well as in man-made form -- across 45 states, in water supplies that are used by between 5 million and 17 million Americans.
The Obama administration is also moving toward new limits on hexavalent chromium, deemed a likely carcinogen by an agency draft report in September, and more than a dozen members of a class of chemicals called volatile organic compounds, EPA Administrator Lisa Jackson told the Senate Environment and Public Works Committee today.
Speaking just after a testy exchange in which Sen. John Barrasso (R-Wyo.) accused EPA of unleashing an "onslaught of job-crushing regulations," Jackson said her agency's eventual rules will be "sensible and practical."
"While we've put in place standards to address more than 90 drinking water contaminants, there are many more contaminants of emerging concern, which science has only recently allowed us to detect at very low levels," she said in her opening statement. "We need to keep pace with the increasing knowledge and potential public health implications from the growing number of chemicals that may be present in our products, our water and our bodies."
The change was praised by environmental groups and congressional allies such as Environment and Public Works Chairwoman Barbara Boxer (D-Calif.), who has introduced several bills that would set limits on perchlorate in drinking water.
"After calling for this standard for over eight years, I was so pleased to hear Administrator Jackson's wonderful news that we are finally going to protect our families from perchlorate," Boxer said.
Some critics have questioned the need for a perchlorate standard, especially since the Bush administration decided in 2008 that it was not yet appropriate to move forward. An analysis released last year by EPA's inspector general concluded that limiting perchlorate by itself would not present "a meaningful opportunity to lower the public's risk" (Greenwire, April 21, 2010).
The office was looking at the standard of 6 parts per billion (ppb) that has been put in place by state regulators in California. Environmental groups said that these levels of perchlorate could have greater impacts than the inspector general concluded because similar chemicals are also found in drinking water.
Natural Resources Defense Council senior scientist Jennifer Sass said today she doubts EPA has a specific ppb number in mind for perchlorate but the agency may be considering tap water limits within a certain range.
"The only new science coming out is showing effects at lower and lower levels," she said in an interview. "No science is showing that it's less of a concern."
Citing these findings, California lawmakers last month proposed a stricter limit of 1 ppb of perchlorate in drinking water (E&ENews PM, Jan. 7).
Applying these types of rules at a federal level could put local water officials in a tough spot, said Sen. Mike Johanns (R-Neb.) during the hearing yesterday. He and some of his Republican colleagues said excessive costs could be passed along to consumers by the efforts to remove tiny amounts of perchlorate and other toxic chemicals.
"It's one thing for us to sit here in Washington and issue rules and regulations," Johanns said, "but it is quite another thing for the people on the ground delivering the service to make the case to that customer clientele that this is the right course of action."
Coming limits on other carcinogens
In addition to its perchlorate decision, EPA also announced that it would craft new drinking-water limits for as many as 16 types of volatile organic compounds (VOCs) that can cause cancer -- only half of them currently subject to regulation.
The agency's move to tackle VOCs as a group is the first step in a process not expected to yield a final rule for at least four years, and no decisions have been made on what a tap-water standard for the 16 chemicals would look like, EPA said in a fact sheet on its plan. Addressing related contaminants together was a central plank in a streamlined drinking-water strategy that was first outlined by Jackson nearly one year ago (Greenwire, March 22, 2010).
EPA bills its decision to look at water contaminants in groups as aimed at minimizing compliance costs and speeding up implementation. The agency examines whether chemicals are likely to occur together, whether they have "a similar health endpoint," and whether their presence in tap water can be addressed with the same technological screening and treatment methods, EPA noted in its fact sheet.
The two most high-profile chemicals in the new group of 16 are tetrachloroethylene, or PCE, and trichloroethylene, or TCE, both of which were pinpointed for new tap-water limits in Jackson's 2010 speech. Those dry-cleaning solvents, found in the groundwater near a sizable number of Superfund sites, are linked to several types of cancer as well as developmental disabilities in exposed infants.
Other VOCs in the group of 16 being considered for a new drinking water standard are six now-regulated toxins: vinyl chloride, benzene, carbon tetrachloride, 1,2-dichloroethane, 1,2-dichloropropane and dichloromethane, in addition to the presently unregulated aniline, benzyl chloride, 1,3-butadiene, 1,1-dichloroethane, nitrobenzene, oxirane methyl, 1,2,3-trichloropropane and urethane.