Perchlorate Standard in Massachusetts

The nation's first drinking water standard for perchlorate has been proposed by the state of Massachusetts at a level of 2 ppb, an order of magnitude lower than the EPA's current "reference dose" (recommended safe limit).  The state claims that the proposal reflects growing scientific evidence of exposure to perchlorate from various pathways other than water. The article did not mention the growing evidence that perchlorate occurs naturally as a result of energetic atmospheric chemistries.

Separately, an EPA advisory committee on children's health has submitted a letter to EPA Administrator Stephen Johnson urging the agency to set a federal water standard for perchlorate and/or to issue a health advisory for drinking water that will specifically protect infants. At issue with the current clean-up goal of 24.5 ppb for Superfund toxic waste sites, the committee cites factors such as infants' extra fluid needs and lighter weights as factors in their opinion. Various toxicological experts have gone on record as saying that long-term exposure to perchlorate at levels as high as 200 ppb are generally expected to be safe, and included sensitive sub-populations such as nursing infants and fetuses.

An article reflecting this news and its attendand political controversy was published in the March 15, 2006 issue of the Wall Street Journal.