Water Utilities Lack Proper Filters For Weed-Killer

Results from a federal drinking water monitoring program show that many public water companies are ineffective at removing a widely used weed-killer from their water supplies.

As the Huffington Post Investigative Fund reported earlier this week, the Environmental Protection Agency has failed to notify the public about data showing that the herbicide atrazine has been found at levels above the federal safety limit in drinking water in at least four states. Atrazine has been studied for its potential link to breast cancer, prostate cancer, and birth defects, and the EPA considers it to be a potential endocrine disruptor. It is banned in the European Union.
But the EPA’s data also reveals that many public water filtration systems are not removing the herbicide. In many places, atrazine levels in untreated water sources such as rivers directly match the levels that come out of the tap.

A carbon filter with granular activated carbon — in other words, a giant Brita-like filter — should absorb all or most of the atrazine. But the EPA’s atrazine monitoring data shows that many water utilities in the Corn Belt do not use carbon filtration. Many use rapid sand filters instead. They are cheaper and last longer, but are unable to remove organic compounds such as PCBs, phthalates, pharmaceuticals, and pesticides such as atrazine.

“Carbon filters might have to be replaced every couple of years whereas sand filters could last 20 to 30 years,” said Alan Roberson, director of security and regulatory affairs at the American Water Works Association, a non-profit organization representing water utilities.

To recover the cost of filtering atrazine, water companies in six states are preparing a lawsuit against the makers of atrazine, the Swiss company Syngenta.

http://www.huffingtonpost.com/2009/08/27/water-utilities-lack-prop_n_270714.html