This symbol indicates that the food has been irradiated, a method of food preservation approved for use on produce by the Food and Drug Administration.
Irradiation kills microorganisms that spoil food.
Irradiated food isn't radioactive, irradiation leaves no residue on food, and it doesn't affect flavor. Proponents of irradiation say it reduces the need for chemicals typically used to keep food fresh longer. Those who oppose irradiation say essential nutrients in food may be destroyed, that eating food that's been irradiated may cause cancer or other debilitating conditions, and that irradiation may be hazardous to the employees and residents of the area surrounding a food irradiation site. But studies haven't conclusively identified any harmful effects of food irradiation. American Institute for Preventive Medicine.