Chances are you've never seen the word "irradiation" on food in a supermarket.

And if the U.S. Food and Drug Administration approves a proposal to relax the labeling requirements on irradiated foods, you probably never will. A 90-day public comment period on this proposal ends Tuesday.

Since 1986, the FDA has allowed food companies to zap certain foods -- including spices, ground beef, and poultry -- with high-energy rays to kill harmful bacteria.

But the agency also has required those products to carry the "radura" label -- a seedling inside a dashed green circle -- and a message saying that the food has been irradiated. Leery of spooking shoppers, nearly all food makers have opted to stay away from the technology -- and its mandatory label.

"The words 'irradiation' and 'radiation' raise a red flag for the consumer," said Jeffrey Barach, who directs the Center for Technical and Laboratory Services at the Grocery Manufacturers Association, a trade group representing most major food companies.

For years, the FDA declined to act on industry requests to relax the labeling requirements as well as expand the list of foods approved for irradiation.