BACKGROUND: California's Public Health Goal for Perchlorate
On March 11, 2004, Cal/EPA issued a Public Health Goal1 for perchlorate of six parts per billion (ppb)2 in drinking water, simultaneously indicating it will consider the findings of the ongoing National Academy of Sciences (NAS) review of perchlorate science before adopting a final water standard for perchlorate.
In January 2004, each of the three peer reviewers submitted a separate report of their analysis. All three disagreed with OEHHA - and with one another - in analyzing the science underlying consideration of setting a perchlorate standard.
In June 2003, the NAS convened a panel of experts to review a large body of credible research on perchlorate. This review provides an internationally respected, neutral forum, receptive to all data. The NAS report will be completed later this year.
In June 2003, further consideration of the Public Health Goal was put on hold pending completion of a scientific peer review of the risk assessment, upon which the draft Public Health Goal was based. Three researchers affiliated with the University of California undertook the peer review late in 2003.
In December 2002, the Office of Environmental Health Hazard Assessment (OEHHA) -an office that operates under the auspices of the California Environmental Protection Agency (Cal/EPA) - proposed a Public Health Goal for perchlorate of two-to-six ppb in drinking water.
1A Public Health Goal is defined as a concentration of a substance in drinking water that poses no risk if consumed for a lifetime. It is the first step in the regulatory process for setting a formal drinking water standard for the substance, but generally is the only part of the standard-setting process that examines the science surrounding potential health impacts.
2One part per billion is roughly equal to ½ teaspoon of water in an Olympic-sized pool.