WASHINGTON, Aug. 12 -- Every year, food manufacturers in the United States make hundreds of quiet decisions that determine what chemicals Americans consume. Under a regulatory framework unchanged in its essentials since the Eisenhower administration, those decisions rarely involve the government agency charged with protecting the food supply.

The Food and Drug Administration on Sunday moved to change that. The agency published a proposed rule that would require food manufacturers, for the first time, to formally notify the FDA whenever they determine a substance qualifies as "Generally Recognized as Safe," a designation known as GRAS that has become the primary pathway for introducing chemical ingredients into the American food supply wi...