A common agricultural herbicide that is banned in Europe is contaminating watersheds and drinking water across the nation, including in Iowa, according to a report by the Natural Resources Defense Council, an environmental watchdog group.
The NRDC says the U.S. Environmental Protection Agency is ignoring the potential public health risks associated with atrazine, which was banned by the European Union in 2004. The report documented spikes in atrazine in the water supplies of Midwestern and Southern towns in agricultural areas, where the herbicide is applied to the vast majority of corn, sorghum and sugar cane fields.
The study included data from two Iowa watersheds — the Nishnabotna River in western Iowa, where 82 percent of samples taken contained atrazine, and Wolf Creek in Black Hawk and Grundy counties where 96 percent of samples taken contained atrazine. In Wolf Creek samples, the maximum peak atrazine concentration was 10 parts per billion (ppb), more than three times the EPA standard atrazine level for drinking water.
The study also looked at 12 public water systems in southern Iowa. The highest concentration of atrazine in raw water was found at the Winterset Water Treatment Plant in Madison County, where the maximum concentration was 47.5 ppb. This system serves approximately 4,768 people and uses water from Cedar Lake.
Atrazine can interfere with the body’s hormonal activity and the development of reproductive organs. The NRDC says the U.S. government looks at annual average levels of the chemical in drinking-water systems, but misses spikes likely to occur after rain and springtime application of the herbicide.
“The adverse reproductive effects of atrazine have been seen in amphibians, mammals and humans even at low levels of exposure,” the report says. “Concentrations as low as 0.1 ppb have been shown to alter the development of sex characteristics in male frogs. When exposure coincides with the development of the brain and reproductive organs, that timing may be even more critical than the dose. Also of great concern is the potential for atrazine to act synergistically with other pesticides to increase their toxic effects.”
According to an investigation by the New York Times, 33 million Americans have been exposed to atrazine through their taps.