Senate Hearing On Perchlorate And TCE In Water

May 6: Senate Environment and Pubic Works Committee, Chaired by Senator Barbara Boxer (D-CA) held a hearing entitled, Perchlorate and TCE in Water. Witnesses testifying at the hearing included: Benjamin Grumbles, Assistant Administrator for Water, U.S. EPA; representatives of the California EPA; Ohio EPA; the Association of State Drinking Water Administrators (ASDWA); Massachusetts Department of Environmental Protection; a State of New York legislator; HealthRisk Strategies; Medical University of South Carolina; and the Environmental Working Group. Additionally, Senator Boxer and Ranking Member James Inhofe delivered opening statements.

Senator Boxer said, "In fact, today we will hear about EPA’s particularly disturbing failures to address significant risks to our families from two widespread drinking water contaminants: perchlorate and trichloroethylene, usually just called 'TCE.' Perchlorate is used to make rocket fuel, but when it gets into drinking water, this toxic chemical can interfere with the thyroid and affect hormone systems, which control the way the body develops. Infants and pregnant women are especially vulnerable to perchlorate. Researchers have found that over 20 million Americans’ drinking water supplies contain perchlorate. GAO found in 2005 that there were nearly 400 sites in 35 states contaminated with perchlorate. My state of California had 106 sites. . . And we know that we are exposed to perchlorate from many sources, not just drinking water. A January 2008 study by the FDA found perchlorate in 74% of all foods tested, including baby food."

Boxer said that EPA had done "very little" to address the problem. She said, "I told EPA last week that if the Bush Administration failed to protect our people, Congress would step in. I have two bills to protect people from perchlorate contamination. The first bill, the “Perchlorate Monitoring and Right to Know Act,” S. 24, says that EPA is to restore the rule requiring that drinking water be tested for perchlorate, and that the results of those tests must be disclosed to the public. My second bill, the “Protecting Pregnant Women and Children from Perchlorate Act,” S. 150, requires EPA to quickly set a perchlorate standard for drinking water that protects pregnant women and children. In addition, Senator Clinton, Senator Dole, myself, and several colleagues have a bill, the “TCE Reduction Act,” S. 1911, that would protect people exposed the TCE."

Senator Inhofe indicated that he was opposed to all three of these pieces of legislation mentioned by Senator Boxer. He said, "Each bill assumes that the scientific data and findings are complete and that they require the Environmental Protection Agency to establish a Maximum Contaminant Level, or MCL, within a specified amount of time for both perchlorate and TCE. My concern isn’t that these chemicals may be harmful to human health at a certain level, but rather that politicians feel compelled to introduce legislation forcing EPA’s hand on what could become a 'contaminant of the month' scenario without scientific backing. It should also be noted that TCE already has a set MCL based on principals outlined in the Safe Drinking Water Act. . .

"The legislative approach taken in S. 24, S. 150, and S. 1911 is simply politicians meddling in the scientific process clearly laid out in the Safe Drinking Water Act. Mike Baker from the Ohio Environmental Protection Agency will speak on behalf of the Association of State Drinking Water Administrators about the current process and the concern of legislating contaminants rather than following the process outlined in the Safe Drinking Water Act. . ." [See WIMS 1/3/07]

EPA testified that the Agency has been working on the science related to perchlorate for more than ten years. "In 2003, EPA sent its January 2002 external review draft of the perchlorate risk assessment to the National Academy of Sciences (NAS) for review. The NAS panel released a report in January 2005 which recommended that the Agency use a reference dose (RfD) of 0.0007 mg/kg/day (0.7 µg/kg/day) based on a human study (Greer et al., 2002). The RfD is an estimate (with uncertainty spanning perhaps an order of magnitude) of a daily oral exposure to the human population (including sensitive subgroups) that is likely to be without an appreciable risk of adverse effects during a lifetime. EPA endorsed their recommendation and used the NAS panel report "Health Implications of Perchlorate Ingestion” as the basis for establishing its RfD which was subsequently posted to the Integrated Risk Information System (IRIS) database in February 2005."

He said in January 2006, EPA issued guidance for contaminated sites which recommended a revised preliminary remediation goal (PRG) of 24.5 ppb perchlorate in water. The PRG was calculated from EPA’s RfD using standard exposure values of 70 kg body weight and 2 liters of water consumed per day. This calculation provides the drinking water equivalent level, assuming
no other sources of perchlorate exposure." He also said, "In addition, if a state has promulgated a drinking water standard for perchlorate (e.g., Massachusetts adopted 2 ppb as a drinking water standard), that value would be considered an Applicable or Relevant and Appropriate Requirement (ARAR) and used as the ground water cleanup level for sites in that state."

He indicated that the Agency has "significant concerns with the bills introduced by Senators Boxer and Clinton. With respect to drinking water our primary concern with these bills is that they return the Agency to the time before 1996 when Congress dictated the drinking water regulations developed by the Agency." He concluded saying, the Agency is "working expeditiously to address potential risks from perchlorate and to evaluate the need for and feasibility of a stronger standard for TCE using this framework. We believe this framework is sound, and respectfully request that you allow us time to complete the required analyses and determinations to ensure appropriate science-based protection of public health from these and other contaminants, as envisioned in the 1996 amendments. As noted above, we are committed to making a final regulatory determination for perchlorate by the end of 2008, and for TCE as soon as the necessary analyses have been completed."

Access the hearing website for links to all testimony, opening statements and a webcast (click here). [*Water/Drink, *Toxics]