NPR Story
1:00 am
Fri October 18, 2013

GMO Labeling Initiative Raises Environmental Concerns

If you’ve turned on your TV in Washington over the past few weeks, you’ve probably heard countless commercials for Initiative 522.

The ballot measure proposes to label genetically modified foods sold in the state. But behind all the campaign rhetoric, some scientists have raised environmental questions about genetically modified crops.

And those researchers have reached differing conclusions about the crops’ effect on the environment.

GMOs could be bad for the environment

On one side of the issue, a study found that genetically modified crops cause farmers to spray more herbicides.

Many genetically modified crops –- like corn, cotton, and soybeans -– are engineered to be resistant to the herbicide glyphosate. They’re known as Roundup Ready crops. That means farmers can spray glyphosate to kill weeds and their crops won’t be affected. The problem, say some researchers: weeds are becoming resistant to glyphosate.

Charles Benbrook studies GM crops and herbicide resistance at Washington State University. He said glyphosate-resistant weeds are causing farmers to use older herbicides.

“They pose greater risks to people, and fish, and birds, and other non-target organisms by virtue of their physical and chemical properties and their toxicity profile,” Benbrook said. He said these herbicides can drift onto other farms and gardens, which could kill plants and sicken people.

These new, herbicide-resistant weeds could have been avoided if farmers didn’t rotate Roundup Ready corn with Roundup Ready soybeans year after year, Benbrook said. That means fields are constantly sprayed with glyphosate.

“It’s a single weed management system that relies on one herbicide on half of the cultivated cropland in the United States, for god sake. If the Roundup Ready system had not been so excessively relied upon, we wouldn’t have anywhere near the problem that we do now,” he said.

Benbrook said herbicide tolerant crops can also cause soil in these fields to degrade and nearby water to have elevated levels of glyphosate.

GMOs could be good for the environment

On the other side: genetically modified crop supporters say there isn’t a problem now. If anything, researchers say, genetically modified crops can help solve environmental problems.

Margaret McCormick works with Targeted Growth, an agricultural biotechnology company.

“The farmers don’t have to till their soil as much. There’s a lot of environmental benefits from less tilling – mainly conserving soil fertility, lessening runoff, basically lessening soil erosion,” McCormick said.

She said when farmers use tractors less often, they also use less energy.

McCormick said researchers are also engineering crops to better deal with climate change -- crops that are more drought resistant or need less nitrogen in fertilizers. “We need to make sure we have the seeds that will actually grow and thrive in these environments. The pace of climate change is actually happening far faster than a traditional breeding program usually happens,” McCormick said.

One measure for how high the stakes are on Initiative 522: opponents to the GMO labeling bill have spent more than $17 million fighting it. That’s more money than has ever been spent fighting an initiative in Washington state.

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