RE: U.S. EPA Decision to Regulate Perchlorate

The best available science, federal statute and EPA’s own Office of Inspector General all point to the conclusion that a national perchlorate standard is not needed and would not provide a meaningful public health benefit.

According to EPA guidelines, for a federal standard to be warranted on any compound, three criteria must be met:

  1. The compound must cause an adverse effect on human health.
    PIB response: This requirement is not met. To date, no research has shown an adverse effect in humans exposed to perchlorate, and the National Academy of Sciences has concluded that at exposure levels below 245 parts per billion (ppb), there is no effect on the body.
  2. The compound must be present in drinking water systems at a frequency and level of public health concern.
    PIB Response: This requirement is not met. U.S. EPA’s own research found that where perchlorate was detected in public drinking water systems, 99 percent of those samples had levels below 6.4 ppb; roughly 40 times lower than the exposure level NAS says has no effect.
  3. Regulating the compound must result in a meaningful reduction in risk to public health.
    PIB Response: This requirement is not met. An actual risk to public health from perchlorate has yet to be scientifically established. A case in point is the 2010 EPA Office of Inspector General report which, among other conclusions, stated, “EPA’s perchlorate Reference Dose (RfD) is conservative and protective of public health, and further reducing the perchlorate exposure below the RfD does not effectively lower risk.”
  4. The Perchlorate Information Bureau believes public health is of the utmost importance. Despite 50 years of scientific research that indicate the low levels of perchlorate being detected in the environment have no effect on human health, much is already being done–even in the absence of a regulatory standard–to further ensure public health is protected. Thirteen states have already enacted some form of perchlorate related policy. These states, including California, Texas, Massachusetts, Arizona and Nevada, represent a substantial portion of the perchlorate detections in the U.S.

    As one example California, in enacting its own standard, has already addressed a majority of perchlorate-affected areas in the country, suggesting again that a national standard will be of questionable public health benefit.

    EPA’s determination, despite the overwhelming scientific evidence contradicting it, now starts what will likely be a multi-year process of scientific review and public input before a final decision is made. The public should expect that commitments by President Obama and EPA Administrator Jackson to science-based regulation would be upheld throughout such a process, and that regulations will protect both public health and scarce public resources.

    Relevant Background For Reporters and Editors:

  • NAS Report: In 2005, a special panel of the National Academy of Sciences (NAS) took the unusual step of suggesting a reference dose (RfD) for perchlorate. The RfD is essentially the daily amount of exposure to a compound that can be considered safe for a lifetime. Standard EPA practice is to determine what level of exposure causes an adverse effect and then apply safety factors to that number to calculate the RfD. As a precaution—no adverse effect level has been identified—NAS took the unprecedented step of starting with a non-adverse effect.
    NAS further applied a safety factor of ten to this non-adverse effect level to suggest a perchlorate RfD of 24.5 parts per billion.
  • Exposures above the RfD do not immediately equate to a health risk: It’s important to understand that exposure to levels above 24.5 ppb, if it occurs, does not suggest a health risk. According to the NAS, you have to have ten times the reference dose to even have a measurable effect, and NAS emphasizes that this first effect is non-adverse. Therefore, any exposure above 24.5 ppb, if it occurs, would very likely cause either a non-adverse effect, or no effect at all.

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