Groups representing supermarket stalwarts are challenging a Vermont labeling law. ChinaFotoPress/Getty Images Trade groups representing food industry giants are asking a federal court to strike down a Vermont law that would require companies to label products that contain genetically modified organisms (GMOs).

The law is scheduled to go into effect in July 2016, and would make Vermont the first state to force companies to let consumers know when food products have been genetically engineered via an insertion of DNA from another plant, animal, or micro-organism.

The law will also prohibit manufacturers from describing genetically engineered products as "natural."

Though Food and Drug Administration commissioner Margaret Hamburg has said foods containing GMOs are not "materially different" from those that do not, many consumers worry that there has not yet been enough research on the longterm effects of consuming such products.

In their lawsuit, the Grocery Manufacturers Association, the Snack Food Association, the International Dairy Foods Association, and the National Association of Manufacturers claim that the law would unfairly infringe on their First Amendment rights to free speech, and that it is unreasonable to expect out-of-state producers to create and distribute special packaging just for Vermont.

The complaint, filed Thursday, said the law was additionally unfair because it exempted restaurants and dairy producers from having to comply, thereby protecting Vermont's tourism and cheese industries at the expense of other companies.

"The State is forcing the costs of this experiment on out-of-state companies and citizens to which it is not politically accountable, and it is undermining and impeding the federal government's interest in uniform, nationwide standards for food labeling prescribed by duly authorized expert federal agencies," the complaint said.

Labeling of GMO foods has been a hot-button issue for proponents of organic foods for some time, with the organic-focused grocer Whole Foods voluntarily creating a labeling program of its own last year and the Mexican food chain Chipotle promising to phase out GMOs over time.

The case in Vermont could have wide-ranging implications for how companies can market genetically engineered products, which in 2012 accounted for 93% of soybeans planted in the U.S., and 88% of the nation's corn.

Connecticut and Maine both have labeling laws similar to Vermont's on their books, but those laws will not go into effect unless the states that border them also enact GMO labeling legislation.