News Coverage
SAB Eyes Prioritizing Drinking Water Contaminants For Agency Review
Published August 22, 2008
An EPA advisory panel reviewing a lengthy draft list of risky drinking water contaminants for potential regulation is considering including in its recommendations to EPA suggestions for prioritizing the chemicals on the list for action and possibly grouping some similar chemicals together for review.
The agency released its third draft contaminant candidate list (CCL3), which includes 104 contaminants, in late February. The CCL3 marks the first time EPA sought public nominations for contaminants to consider, as recommended in 2001 by the National Academy of Sciences and EPA’s National Drinking Water Advisory Council. And the draft CCL3 contains nearly double the contaminants on the previous two CCLs.
EPA uses the CCL, which is required under the Safe Drinking Water Act, to identify contaminants that may require future regulation. The CCL helps EPA focus its resources on developing and collecting data, such as occurrence or health effects data, to help it make a regulatory determination about the contaminants on the list.
The list has endured a fair amount of scrutiny from the drinking water and chemical industry, as well as environmentalists, for the way EPA chose the chemicals, and its exclusion of pharmaceuticals and personal care products, as well as perfluorooctanoic acid (PFOA) and other perfluorinated chemicals (PFCs).
During an Aug. 13 conference call, a Science Advisory Board (SAB) panel discussed how it might assist EPA in addressing contaminants of greatest concern, such as by prioritizing and possibly grouping similar types of chemicals. Some SAB members said that while they support the method EPA used in choosing the contaminants for the draft list, the chemicals that are more urgently in need of regulation may be lost in the shuffle because the draft CCL3 is longer than previous lists.
The group is considering how to include in its draft comments some sort of indication to the agency of which chemicals should be regulated first.
“Which compounds need to be regulated?” one panel member asked on the Aug. 13 call. “We’re saying that there’s too many things now that need investigation . . . and there’s no priority.” The panel should be able to help EPA “sharpen the list if possible,” such as pulling some chemicals to the top “that are really bad actors and do need strict regulation,” the panelist said, drawing agreement from other panel members.
Panelists also discussed the idea of grouping chemicals that include similar sources and mechanisms of action. One panelist explained that if EPA looks at individual chemicals, their occurrence data might not be enough to require regulation, “but if you look at them all together, you might say, ‘Gee, they occur a lot.’” Taken together, EPA might decide there is enough of a problem that the chemicals should be regulated, the panelist said.
The panelists’ concerns echoed those voiced by Environmental Working Group Senior Scientist Olga Naidenko, who gave public comment at the meeting. She urged the SAB to include PFOA and pharmaceuticals on the CCL3, as well as consider how drinking water contaminants may be linked, particularly through production.
Naidenko, in response to questions from the panel, noted that the chemical industry tends to substitute one closely related chemical for another in response to regulation -- “something that in future years we’ll have to deal with.” This prompted one SAB panelist to question whether it would make more sense to have the CCL be groups of chemicals rather than individual ones.
Separately, Thomas Mohr, affiliated with the California Groundwater Resources Association, but speaking on his own behalf, asked the panel to look at 1,4-dioxane, a solvent that is being phased out but that he says is increasingly found in groundwater and drinking water and should be added to the CCL3.
“1,4-dioxane is springing up at an increasing frequency,” Mohr said on the call; “it shows up because it’s very persistent and mobile.” Mohr said that while the health effects of the chemical are uncertain, it has been shown to be a carcinogen, and EPA should examine it closely.
During the call, Eric Burneson, chief of EPA’s Target & Analysis Branch in the Office of Ground Water & Drinking Water, said the agency is amenable to the recommendations. He said EPA appreciates the committee’s adherence to the adaptive management approach, distinguishing in the recommendations between what should be altered in the CCL3 and in future CCLs.
But the agency asked for clarification in a number of areas: in dealing with pesticides that are “about to be canceled,” and questions about where the agency should look for additional data when discussing pharmaceuticals and endemic disease rates, as well as questions about a recommendation that particular attention be paid to algal toxins. Burneson clarified for the committee that several algal toxins were included on the CCL3, and the committee members otherwise requested the agency’s concerns in writing, to consider for its next meeting on Oct. 28. The agency plans to publish the final CCL3 in the summer of 2009.
