Investigation into corn pesticide

Courtesy WSJ

The Environmental Protection Agency said Wednesday it is launching an investigation into whether the herbicide atrazine, popular among U.S. corn farmers, causes cancer and birth defects.

"Our examination of atrazine will be based on transparency and sound science, including independent scientific peer review, and will help determine whether a change in EPA's regulatory position on this [herbicide] is appropriate," said Steve Owens, an EPA assistant administrator.

But agribusiness giant Syngenta AG, maker of atrazine for 50 years, said the chemical has already been proved safe. The company, in a recent statement, said the EPA, the World Health Organization and others have previously reviewed the drug and pronounced it safe.

Sherry Ford, a spokeswoman for Syngenta, said the EPA re-licensed atrazine for sale in the U.S. in 2006 and said the chemical wasn't likely to cause cancer.

U.S. corn farmers have come to rely on the herbicide to control weeds in their fields. Ken McCauley, former president of the National Corn Growers Association, said Wednesday that atrazine is used on most corn fields in the U.S.

Syngenta's Ms. Ford said about 60% of the corn, 75% of the sorghum and 90% of sugarcane grown in the U.S. is done so with the aid of atrazine.

"When EPA re-registered it in 2006...they estimated that atrazine saves corn farmers about $28 per acre in herbicide costs and yield advantages," Ms. Ford said.

Mr. McCauley, who farms 4,500 acres in Kansas, said he relies on the herbicide to "enhance" the effects of other chemicals. While he and many farmers rely heavily on atrazine, they use less of it than when the chemical was first sold on the market. Initially, atrazine was used as a primary herbicide and farmers would use about three to five pounds per acre. Now, Mr. McCauley said, it is common practice to use about a pound or less.

Use of the herbicide makes it possible for many corn producers to conduct "no-till" farming, Mr. McCauley said, a practice that eliminates plowing to protect against soil erosion.

U.S. farmers are currently in the midst of harvest and are expected to produce about 13 billion bushels of corn on 80 million acres of land, according to USDA data.

Atrazine is already regulated by the EPA, which warns of human health threats from contamination of drinking water. The EPA said atrazine may cause "congestion of heart, lungs and kidneys; low blood pressure; muscle spasms; weight loss; damage to adrenal glands" if "people are exposed to it at levels above [three parts per billion] for relatively short periods of time."