A federal judge has dismissed a class-action lawsuit against General Mills over the company's use of "natural" to describe the oats in its Nature Valley granola bars.

The group of citizens who filed the lawsuit last August argued General Mills misled the public by claiming the bars were "Made With 100% Natural Whole Grain Oats." The plaintiffs said a third-party laboratory detected 0.45 parts per million of glyphosate in the bars and believe the oats are "most likely the source" of the commonly used herbicide.

But Judge Michael J. Davis of U.S. District Court of Minnesota said the plaintiffs' particular claims made in the case "are simply not plausible." Davis said the plaintiffs' argument holds the Nature Valley bars to more stringent standards than the federal government holds organic products. Foods labeled as organic are allowed to contain chemical pesticide residue of less than 5 percent of the Environmental Protection Agency's tolerance level.

The term "natural" lacks a federal standard, and the case hinged on what is reasonable for a consumer to assume about such a claim. Davis said consumers either conflate the meaning of natural foods with organic foods — which do have specific federal standards — or they believe an organic label is more restrictive than a natural label.

In his ruling last week, Davis added that "even if the glyphosate traces are present on the oats, there is no allegation that the oats, themselves, are not natural. The packaging does not state that the product, as a whole, is '100% Natural.' "

The case again raises the unsettled issue of what "natural" means on food packaging. Last spring, the FDA requested public comments on the topic, indicating the agency's intention of creating a definition for the label, but has not published any new information since the comment period closed last May. General Mills, Austin-based Hormel Foods Corp., Dole and other food manufacturers have been sued in the past over use of the term. Post Foods is facing pending litigation for its use of "natural" on its Shredded Wheat cereal boxes.

General Mills said Monday it is "pleased with the court's ruling."