Common Weed Killer Contaminates Drinking Water

Atrazine effects can tinker with sexual development of animals—including humans—at very low levels.

September 8, 2009

Pesticides don't stay where they're sprayed; they can wind up in drinking water, too.

RODALE NEWS, EMMAUS, PA—A new Natural Resources Defense Council (NRDC) report found that spikes in the water levels of atrazine, a common herbicide banned throughout Europe (but still legal here in the U.S.) could pose a public health risk. The hormone-disrupting chemical is used extensively in corn and sugarcane farming, but research has linked environmentally relevant levels of the herbicide with suppressed immune systems, thyroid problems, aggression, cancer, birth defects, learning disabilities, and sexual development issues, mainly, the feminization of males. "When you start altering developmental patterns, affecting hormone, and neurological and immune status, you're talking about setting up an organism for life-long health defects and behavioral changes," explains Warren Porter, PhD, professor of zoology and environmental toxicology at the University of Wisconsin-Madison.


THE DETAILS: NRDC analyzed the results of surface water and drinking water monitoring required by the U.S. Environmental Protection Agency (EPA) across the heavily farmed Midwest and southern states, and found that all the surface water displayed atrazine contamination. Watersheds in Indiana, Missouri, and Nebraska had the highest peak concentrations. Atrazine, which is manufactured primarily by Syngenta, was also found in more than 90 percent of the tested samples, taken from 139 drinking water systems. NRDC also says the EPA is ignoring the spikes that occur in the spring following atrazine application and again after summer rains.

WHAT IT MEANS: You may have heard about research tying atrazine to male frogs that develop female sexual characteristics. But the same hormones that affect sexual brain development in frogs affects human, too. Spikes in atrazine water contamination are particularly concerning, Porter says, because of the effect that low levels of the herbicide can have on fetuses and young infants. The chemical is the second most used herbicide in the country. Dr. Paul Winchester and colleagues in Indiana have linked conception during peak levels of atrazine and fertilizer levels in water (April through July) with a higher risk of babies born with birth defects and to reduced math and language skills on high school IQ tests. Studies have also linked atrazine to menstrual problems, and to cases of male frogs and deer developing both male and female sex organs.

The kicker? We don't even need it. The U.S. Department of Agriculture estimates that a ban on atrazine would result in crop losses of 1 percent.

Here's what you can do to help get this chemical out of our environment—and our bodies.

• For now, filter it out. In parts of Europe, where atrazine was banned more than a decade ago, there has been no decrease in atrazine in ground water, so it's clear it persists in our environment. To protect yourself, use a filter that is certified by NSF International to meet American National Standards Institute Standard 53 for VOC (volatile organic compound) reduction. This will significantly reduce levels of atrazine and other pesticides.

• Vote with your dollar. Buy organic whenever you can, and if possible, grow your some of own food or purchase it from a local farmer, so you can ask about farming methods. This will keep synthetic pesticides and fertilizers linked to dozens of ailments out of our ground and water.

• Get it banned. Call your legislators and let them know you support organic agriculture, and want dangerous farming chemicals like atrazine put out of commission.