Does Irradiation Make Foods Radioactive?

(From The American Dietetic Association Position: Food irradiation, and the Utah State University Extension Fact Sheet)

Radioactivity in foods could only occur if the foods were contaminated with a radioactive substance, or by penetration of energy into the nuclei of the atoms that make up the food. In food irradiation, the food itself never contacts a radioactive substance, and the ionizing radiation used is not strong enough to disintegrate the nucleus of even one atom of a food molecule. A small number of new compounds are formed when food is irradiated, just as new compounds are formed when food is exposed to heat. Early research described these new compounds as "unique radiolytic products" because they were identified after food was irradiated (8). Subsequent investigations have determined that free radicals and other compounds produced during irradiation are identical to those formed during cooking, steaming, roasting, pasteurization, freezing, and other forms of food preparation (8,10,12). Free radicals are even produced during the natural ripening of fruits and vegetables (22). All reliable scientific evidence, based on animal feeding tests and consumption by human volunteers, indicates that these products pose no unique risk to human beings. In fact, people requiring the safest food, hospital patients receiving bone marrow transplants, are routinely given irradiated foods. Furthermore, because spices, being of tropical origin, are often microbe laden, irradiated spices are preferred for routine use in hospital foodservice for patients. Thus, as with pasteurization, the evidence suggests that food irradiation can make a quality food supply better.


Prepared Summer 1997 by Bernadene Magnuson, Ph.D.
University of Idaho, Dept. of Food Science and Toxicology - EXTOXNET FAQ Team.