August 23, 2009

Weed-killer in the water supply?

Some water-supply systems in the United States have had spikes in levels of atrazine, a commonly used weed-killer, The New York Times reports.

The high levels have lasted for as long as a month, the newspaper said, but in some cases residents who use the water for drinking do not learn of the chemical's presence. Water suppliers are not required to monitor atrazine levels.

Because atrazine is used on lawns, golf courses and farmland, it tends to wash into reservoirs and other water sources. Syngenta, which manufactures most of the atrazine used in the United States, has been sued by 46 water systems, arguing it should pay for atrazine removal.

The Environmental Protection Agency told the Times the levels it sets are many times lower than concentrations that have caused health problems in animal tests. Syngenta is fighting the lawsuits and says they have no foundation.

Linda Birnbaum, head of the National Institute of Environmental Health Sciences, said pregnant women, at least, should be warned of the presence of atrazine in drinking water.

I'm very concerned about the general population's exposure to atrazine, she said. We don't really know what these chemicals do to fetuses or prepubescent children.