The effects of perchlorate in drinking water

Dec. 17, 2014

BIRMINGHAM — In Water Technology’s December issue, Technical Editor Dr. Joseph Cotruvo writes about perchlorate.

BIRMINGHAM — In Water Technology’s December Professor POU/POE, Technical Editor Dr. Joseph Cotruvo writes about perchlorate in drinking water.

In the article, Cotruvo explains that perchlorate is one of numerous anions competing with iodide transport that may cause indirect neurological and thyroid problems in people of high risk at sustained, high enough doses.

Cotruvo also discusses in the article how perchlorate can be present in amounts of parts per billion (ppb) in produce, dairy products and some fertilizers, adding, "It is not metabolized after ingestion and is excreted unchanged with a half-life of eight to 12 hours."

He continues, "Perchlorate and other anions in the diet, (nitrate, chlorate, bromide), smoking (thiocyanate) and in drinking waters compete with iodide transport to the thyroid, which can reduce production of thyroid hormones, increasing the risk of hypothyroidism if iodine intake is not adequate. Perchlorate is more potent on a unit basis than the other anions, but they are present in much greater quantities than perchlorate in the total diet."

Infants and pregnant women with inadequate iodine intake face the greatest potential health risks of excess perchlorate exposure, adds Cotruvo in the article.

Cotruvo reports that treatment technologies for perchlorate include anion exchange, reverse osmosis (RO) and potentially catalytic reduction and granular activated carbon (GAC).

"In 2008, EPA developed an interim [Drinking Water Health Advisory] of 15 ppb based upon the NRC recommendation. California’s MCL is 6 ppb and Massachusetts’ is 2 ppb," notes Cotruvo in the article. "As of EPA’s 2011 determination to regulate perchlorate in drinking water, it is working on a proposed regulation that was originally expected in 2013, but has been delayed."

You can find the entire December Professor POU/POE on perchlorate in drinking water here.