WASHINGTON – The U.S. House on Thursday passed the nation's first federal law that requires food distributors to label products that contain genetically modified organisms, known as GMOs.

The House, which earlier this year approved a bill to ban mandatory on-package GMO labels, reversed course and accepted a Senate compromise that will force food distributors to disclose the presence of genetically engineered ingredients with words, a symbol or a smartphone scan code.

Skeptics of genetically modified foods have long pushed for tighter regulation because they worry about possible health and environmental risks. The industry says those fears are misplaced, but food companies generally prefer nationwide rules to a state-by-state approach.

In a speech before the House vote, Rep. Collin Peterson of Minnesota, the ranking Democrat on the House Agriculture Committee and a supporter of voluntary GMO labels, said the fact that states were starting to adopt their own laws made passage of the Senate bill necessary.

"This legislation is needed to avoid a situation where 50 states set up 50 different labels," Peterson said, "which would only create confusion for consumers, farmers and food companies."

The vote was 306-117. Seven of Minnesota's eight House members, including four Democrats and three Republicans, voted for the bill. Rep. Keith Ellison did not vote because he was in Minnesota for the funeral of Philando Castile, who was shot to death last week by a police officer.

The labeling now heads to the White House, where President Obama has indicated he will sign it.

Many consumer groups opposed the labeling bill, saying the scan code would be confusing and hard to access. Opponents also contended that the bill's definitions of genetic engineering could be narrowly interpreted to exclude thousands of products.

Supporters of the bill said the scan code's presence on food packages would signal the presence of GMOs, just as words or a symbol would, and allow buyers who do not want to eat genetically engineered products a choice.

The food industry, which failed in its attempt to get a national ban on mandatory on-package GMO disclosure, supported the Senate compromise.

The bill supersedes a state labeling law that took effect July 1 in Vermont. The federal bill also pre-empts future state labeling laws.

Minnesota's food and agriculture industries wanted a voluntary GMO labeling standard, but eventually supported the compromise. General Mills and Hormel have already changed labels to comply with the Vermont law, along with other major brands, such as Mars candies and Campbell's Soup. Those labels appear to meet the requirements of the federal law, but the U.S. Department of Agriculture (USDA) will offer the definitive answer.

"Today is a very good day for consumers and for farmers, including our member-owners," Land O'Lakes CEO Chris Policinski said in a statement. "This bill lets food manufacturers engage directly with consumers in an orderly, ongoing, factual dialogue regarding where their food comes from."

The lobbying battle now shifts to the USDA, which has two years to develop definitions of genetic engineering for mandatory labeling purposes. The USDA will set other rules for implementation.

Labeling advocates will fight to keep the definition of genetic engineering as broad as possible.

A major concern critics noted with the bill was its distinction between foods that contain GMOs and foods that were made with GMOs but contain virtually no traces of them after processing.

The former would need to be labeled. Critics fear that the latter will not, saying that opens the door to having products made with sugar beets as well as vegetable oil exempted from labels.

The smartphone code, which designates the presence of GMOs, is another contentious piece of the bill. Its appearance on packages will let consumers know the product contains GMOs. But critics worry that its use in lieu of words or a USDA-developed symbol will confuse consumers.

To that end, the bill requires the USDA to study consumer problems with the scan code within a year after it goes into use.

Jim Spencer • 612-270-1266