Ten Most Commonly Asked Questions About Food Irradiation


In September 1992, USDA's Food Safety and Inspection Service approved guidlines for use of irradiation in raw, packaged poultry. The FSIS decision followed a May 1990 FDA rule, which concluded that poultry irradiation at the absorbed dose of 3 kiloGray does not pose a safety hazard to consumers and is effective in controlling foodborne illness.

Following are commonly asked questions and answers about food irradiation.

1. Why is food irradiated?

Food is irradiated to make it safer and more resistant to spoilage. Irradiation detroys insects, fungi or bacteria that cause human disease or cause food to spoil. Irradiation makes it possible to keep food longer and in better condition.

Because irradiation destroys disease causing bacteria, the process has been used by hospitals to sterilize food for immunocompromised patients.

2. Are irradiated foods still nutritious?

Yes, irradiated foods are wholesome and nutritious. In fact, even at the higher doses of irradiation used to extend shelf-life or control harmful bacteria, nutritional losses are less than, or about the same as cooking and freezing. At lower doses, nutrient losses are either not measurable or insignificant. The fact is, all forms of food processing -- cooking, freezing, canning, and even storing foods -- lower the amounts of some nutrients.

Irradiation produces virtually no heat within food, and most people cannot detect any changes in flavor or texture.

3. Does irradiation make food radioactive?

No. The energy used in food irradiation is not strong enough to cause food to become radioactive. Irradiation involves passing food through an irradiation field, but the food never touches a radioactive substance. During irradiation, energy passes through food much like a ray of light passes through a window. This energy destroys most of the bacteria that can cause disease, yet allows food to retain its high quality.

Since the energy involved in irradiation is not strong enough to change the atoms of the food, and since the food never actually touches the radioactive source, the food cannot become radioactive.

4. Does eating irradiated food present health risks?

No. Scientists from the Food and Drug Administration, U.S. Department of Agriculture, U.S. Department of Energy, as well as from many universities within the United States reviewed several hundred studies on the effects of food irradiation before reaching conclusions about its safety.

Independant scientific committees in Denmark, Sweden, the United Kingdom, Canada and the World Health Organization have also endoresed food irradiation. Food irradiation has been approved in 37 countries for more than 40 products.

5. Does irradiation destroy all bacteria, resulting in a sterile product?

No. Irradiation pasteurizes food by using energy, just as milk is pasteurized using heat. At the level used, most harmful bacteria will be destroyed. Afterwards, surviving bacteria could start to multiply if the food were mishandled; for example, stored at an improper temperature. The level of irradiation used also does not kill certain spoilage organisms. This is for the protection of consumers. Spoilage bacteria will multiply and alert consumbers not to use a product which has been improperly handled.

As with any food, consumers must take appropriate precautions, such as refrigeration and proper handling and cooking, to make sure that potentiall harmful organisms do not present a problem.

6. Does irradiation cause chemical changes in food, perhaps producting substances which are not present in non-irradiated foods?

Any kind of processing causes changes in food. Heat produces chemicals that could be called "thermolytic products", while irradiation produces similar chemicals called "radiolytic products". Radiolytic products are so minor they are measured in parts ber billion and can only be detected with sensitive laboratory equipment. Thermolytic products, on the other hand, can be smelled, tasted, and seen.

"Free Radicals" are atoms or molecules that are unstable and very reactive. They can be formed during irradiation, and also by toasting, frying, freeze-drying, but they quickly change into other, more stabile forms.

Despite extensive research, there is no evidence that irradiated foods present any increased risk of exposure to harmful substances over conventionally processed foods.

7. Will my risk of radiation exposure increase significantly if I live next to an irradiation processing plant?

No. In fact you receive more radiation exposure during a transcontinental airline flight. Irradiation facilities must include many safety features to prevent both environmental and worker exposure. A food irradiation plant is not a nuclear reactor. There is no chance of meltdown. The use and tranportation of radioactive materials -- including the equipment and the facilities in which they are used -- is closely monitered by the Nuclear Regulatory Commission, state agencies, and the Department of Transportation.

8. For what other purposes is irradiation technology now used in the United States?

Irradiation is used for sterilizing medical products such as surgical gloves, destroying bacteria in cosmetics, making nonstick cookware coatings, purifying wool, performaing security checks on hand luggage at airports, and making tires more durable.

9. Are irradiated foods on the U.S. market now?

Until recently only bulk dried spices were irradiated in the United States. Since January 1992 irradiated produce has begun to appear in some American supermarkets. At least a dozen different irradiated foods are being sold.

10. How can irradiated foods be identified in the market?

By law all irradiated foods must be by labeled with the international symbol for irradiation, simple green petals (representing the food) in a broken circle (representing the rays from the energy source). This symbols must be accompanied by the words, "Treated by Irradiation" or "Treated with Radiation".


For more information about food irradiation,
call the Meat and Poultry Hotline,
1-800-535-4555.
In the Washington, D.C. area,
call (202)720-3333.


United States Department of Agriculture
Food Safety and Inspection Service
Revised Augues 1993