Federal standard for perchlorate in drinking water sound, study says
In a sign of the way the Environmental Protection Agency may be leaning on a drinking-water contaminant common to California, an inspector general's report has concluded that current standards are "conservative and protective of human health."
California has one of the strictest safety standards in the nation for the chemical, widely used in the aerospace and defense industries. Public-health activists have been pushing EPA to adopt a similarly stringent limit for drinking water. Under the Bush dministration, EPA declined to regulate perchlorate under the Safe Drinking Water Act, a decision that was reconsidered by current EPA administrator Lisa P. Jackson.
But an inspector general's report released Monday concludes that the current "reference dose" of 24 parts per billion, four times higher than that of California, is adequate when risk is assessed in the context of other factors affecting sodium iodide uptake in the human thyroid. Further lowering perchlorate standards, the report concluded, "does not effectively lower risk" of fetal brain development problems and other maladies that result from lower iodide uptake.
-- Geoff Mohan
Photo: A sign warns of possible hazards at the shuttered site of the Whittaker-Bermite munitions factory in Santa Clarita, which used perchlorate. Credit: Carlos Chavez / Los Angeles Times