U.S. EPA expects to finish its analysis of the risk posed by hexavalent chromium in drinking water late next year, including potentially "game changing" information about the chemical's link to cancer, Administrator Lisa Jackson told a Senate panel yesterday.
Hexavalent chromium, or chromium-6, was recently thrust into the spotlight after a study by the Environmental Working Group (EWG) found elevated levels of the chemical in more than 30 cities across the country.
"The EWG study alone might have been something that we would dismiss," Jackson told the Environment and Public Works Committee. "But a really important piece of scientific information is that we are in the middle of a peer review that shows that chromium-6 -- which we previously thought was not a problem in water -- is a problem in water and causes cancer. If that's true, that is a game-changing piece of information that will likely mean we have to address it by changing our standards."
Some water utilities and lawmakers have criticized the methodology of the advocacy group's study, which measured levels of chromium-6 in samples of tap water from 35 cities. Because EPA has not yet finished its risk assessment, the public does not have a good idea whether the levels of chromium-6 that were detected in the study are actually a threat, the American Water Works Association said in a recent letter to EPA officials.
Linda Birnbaum, director of the National Institute of Environmental Health Sciences, told lawmakers yesterday that the study was not definitive, but it signals "that there might be a problem."
Yesterday's hearing was called by EPW Chairwoman Barbara Boxer (D-Calif.), who proposed legislation last week that would require EPA to limit chromium-6 and other chemicals found in drinking water.
Boxer said she is glad EPA is heading toward limits on chromium-6 and perchlorate but that Congress should intervene and force the agency to set limits on the chemicals. Since the Safe Water Drinking Act was last amended in 1996, she said, the agency has not limited any of the "emerging contaminants."
"What Congress wanted to happen was for EPA to begin to move," Boxer said. "They didn't expect that not one emerging contaminant would be regulated from '96 to as we sit here. Not one thing has happened. Nothing."
Given the power shift in Congress, it appears unlikely that the bills will go anywhere, said Matt Dempsey, a spokesman for committee Republicans, in an interview last week (E&E Daily, Jan. 31).
Sens. Mike Johanns (R-Neb.) and John Boozman (R-Ark.) criticized the methodology of the EWG study yesterday, saying subsequent news reports scared the public at a time when EPA has not yet settled on a safe level of chromium-6 in drinking water.
Consumers would pay the price if limits on chromium-6 were based on the "sweeping generalizations" about safety that were prompted by the study, Boozman said.
"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" (Greenwire, Feb. 2).
Jackson said the agency is moving forward quickly on chromium-6, but people should not be afraid about their drinking water in the meantime.
"The American people don't want us to play 'see no evil,'" Jackson told reporters after the hearing. "There's something out there in their water. We have to look for it and we have to tell them that on a day-to-day basis, they can drink the water, but we are moving aggressively to change the standards if we need to."
Chuck Murray, general manager of Fairfax Water, told the committee that regulators should be wary of making chromium-6 the latest "contaminant du jour" before the risk assessment is complete. Despite the findings of the EWG report, the northern Virginia utility did not detect any chromium-6 when it tested its own water, he added.
Meanwhile, many public health experts say that EPA's current limits are outdated. By putting an overall limit on chromium compounds rather than focusing on dangerous chromium-6, the standards do not reflect the current state of the science, said Thomas Burke, a public health professor at Johns Hopkins University.
In the absence of a federal standard on chromium-6, California recently set a draft standard of 0.02 parts per billion. It is tighter than the state's previous standard of 0.06 ppb (Greenwire, Jan. 3).