Irradiation is a process in which food is exposed to high doses of radiation in the form of gamma rays, X-rays or electron beams. Irradiation can kill bacteria in food, both good and bad, but has no effect on the infectious agent that causes mad cow disease, or on viruses, 1 such as those that cause hepatitis.
The long-term health consequences of eating irradiated food are still unknown. Irradiation creates a complex series of reactions that alter the molecular structure of food and create known carcinogens, 2 including benzene, and other toxic chemicals, including toluene. 3 In addition, byproducts of irradiation, called 2-ACBs, which do not occur naturally in any food, have been linked to tumor growth in rats 4 and genetic damage in human cells. 5 Animals fed irradiated foods have died prematurely and suffered mutations, stillbirths, organ damage and nutritional deficiencies. 6
Irradiation can also change the flavor, odor, texture, color and nutritional content of food. 3 For example, yolks of irradiated eggs are more watery and have less color and brightness than non-irradiated eggs. 7 Irradiation also destroys the niacin and vitamins in eggs, including up to 24 percent of vitamin A, at just one-third the radiation level approved by the FDA. 7
Irradiation is used to create a false sense of security about food safety. It is promoted as a solution to the overcrowded and unsanitary conditions on factory farms that make animals susceptible to disease, and to the filthy conditions in slaughterhouses that contaminate meat with bacteria. However, since irradiation may not eliminate all bacteria from foods, and since foods can be contaminated or re-contaminated after having been irradiated, the process does not totally eliminate the possibility of foodborne illness. That is why the USDA recommends the same food-handling practices for irradiated foods as for non-irradiated foods. 9
Food is irradiated to extend its shelf life and kill pests like fruit flies. It uses gamma rays with short wavelengths and high frequencies that penetrate food so rapidly that little or no heat is produced. Microwaving, which uses longer wavelengths, causes foods to heat rapidly. 10
Currently, the US Food and Drug Administration has approved irradiation of foods including meat and poultry, shell eggs, fruits and vegetables, herbs, spices and flour. However, only a few of these approved foods are actually produced commercially; currently, irradiated foods are limited to small amounts of ground beef, spices, and some imported fruit such as papayas. Irradiated foods sold in grocery stores are required to be labeled.