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Environmental Health

Image of Irradiation symbolFood Irradiation  
Information from the University of California - Division of Agricultural and Natural Resources

Frequently Asked Questions About Food Irradiation:

Why should I be interested in irradiated food?    


  •   Irradiation improves food safety and quality. Even though the United States food supply has achieved a high level of safety, hazards exist. The Centers for Disease Control and Prevention has estimated that 76 million illnesses, 325,000 hospitalizations, and 5000 deaths occur each year due to foodborne illness. Although all are at risk, children, people over age 55 or 60, diabetics, and those whose immunity is compromised are especially vulnerable.
  • Irradiation provides extra protection against foodborne illness which is unavailable by any other means. Even when meat, poultry, or eggs are prepared with the most advanced sanitation measures possible, harmful bacteria may be present. Irradiation provides an additional safeguard for the consumer, destroying 99.9% or more of E. coli 0157:H7, Salmonella, Campylobacter, Listeria, or other harmful bacteria that may be in raw food.

High quality tropical fruits can be shipped to California or other states because irradiation destroys harmful fruit flies, such as the Mediterranean fruit fly, before they become an infestation problem in our state.

Irradiation increases the shelf life of several fresh foods because it slows the ripening of fruit and prevents potatoes and onion from sprouting. Spices and herbs have been fumigated to increase safety. Irradiation can replace chemical fumigation, producing safe, high quality spices and herbs.

The U.S. Food and Drug Administration (FDA) may soon approve the use of irradiation to increase the safety of fresh sprouts because it can destroy harmful bacteria that may be under the sprout seed coat. The FDA may also soon approve irradiation of prepared luncheon meats, and other ready-to-eat foods, because the process can increase the safety of such prepackaged foods.

What is food irradiation?

  • Irradiation exposes food to ionizing energy for a specific length of time, depending on the purpose of the treatment. This treatment compliments good manufacturing practices and increases overall food safety.
  • Food is irradiated in a special processing facility where it is exposed to an electron beam, or X-Ray, generated from electricity or gamma rays produced from cobalt 60. The food is monitored to assure that the exact treatment level is achieved.

Is irradiated food safe?

  • Yes. Irradiated foods are safe and wholesome. After reviewing hundreds of studies on the effects of irradiation on food safety and quality, scientists from the U.S. Food and Drug Administration, the U.S. Department of Agriculture, and health organizations such as the World Health Organization, the American Medical Association, and the American Dietetic Association have endorsed the safety of irradiated food. To ensure their health, astronauts have eaten irradiated food since the beginning of the space program.  

Does irradiation cause chromosome damage, cancer, tumors, or other health problems?

  •  No. The FDA has evaluated irradiation for 40 years and found the process to be safe. Numerous scientific studies conducted world wide clearly confirm that there are no health problems or toxicity concerns associated with irradiation.   
Does irradiation make food radioactive?
  •  No. During the irradiation process, food moves through an energy field, but never touches the energy source and does not become radioactive. The amount of energy and type of radiation used to irradiate food is enough to kill foodborne bacteria, but it does not make the food radioactive, just as luggage does not become radioactive after passing through a security checkpoint at the airport.
  • Many common items, such as cotton balls, adhesive bandages, baby bottles, and medical supplies are irradiated for safety. None are made radioactive.

Do I handle irradiated food differently than other foods?

  •  No. Handle irradiated food as you would any other perishable food. Irradiation destroys 99.9% or more of harmful bacteria like E.coli 0157:H7 and Salmonella. However, it reduces by does not destroy all spoilage bacteria. Meat and poultry should still be refrigerated to slow the growth of spoilage bacteria and maintain food quality. Irradiation leaves no chemical residue in the food, so irradiated foods could be accidentally contaminated after treatment; therefore, proper handling and preparation should be followed to assure food safety.  
If thorough cooking destroys harmful bacteria, what is the advantage of irradiated meat and poultry?
  •  Irradiation destroys harmful bacteria before they come into the kitchen. Eating irradiated foods should reduce foodborne illness that results from accidental cross contamination or cooking at too loa a temperature. Food irradiation provides an additional level of protection for consumers.

Is irradiated food still nutritious?

  • Irradiated food is nutritious and flavorful. Nutritional changes produced by irradiation of food are less comparable to those produced when food is cooked or frozen. Thiamin is reduced when pork is irradiated and some vitamin A is reduced when eggs are irradiated, however the difference is so small that it has no effect on the American diet.
  • Changes in the nutritional value of fruits and vegetables are insignificant. Some irradiated fruits may even be more nutritious and flavorful because irradiated fruits can stay on the tree longer than those treated by other methods that guard against the accidental transport of tropical insects.

Is food irradiation approved by the government?

  • Food irradiation has been approved by the Food and Drug Administration after a thorough food safety review. Irradiation is the most researched food technology in U.S. history. Scientists with the FDA have evaluated numerous studies that have examined the safety and nutritional value of irradiated food. The U.S. Department of Agriculture has evaluated and approved irradiation of meat and poultry. Food irradiation has been approved by more than 40 countries worldwide and endorsed for safety by the World Health Organization.

How do I know when food has been irradiated?

  • Irradiated food has a distinctive logo: Image of Irradiation symbol
    and the words "Irradiated" on its packaging. Some may also describe the process as "cold pasteurized" or "electronically pasteurized" for better consumer understanding.

Is worker and community safety protected in food irradiation facilities?

  • Yes. Irradiation facilities are strictly regulated. Facilities using gamma rays must be constructed to withstand earthquakes and other natural disasters without endangering surrounding communities or workers. Electron beam and X-ray facilities must follow the same safeguards used by hospitals. Workers are trained in the safe operation of irradiation equipment, and their personal safety is protected by multifaceted protection system within plants. Companies must follow state and local government requirements as well as those issued by the Environmental Protection Agency, the Occupational and Safety Health Administration, and Department of Transportation.

Who says irradiated food is safe?

  • U.S. Food and Drug Administration
  • U.S. Department of Agriculture
  • American Medical Association
  • American Dietetic Association
  • Centers for Disease Control and Prevention
  • World Health Organization
  • U.S. Public Health Service
  • American Public Health Association
  • California Environmental Health Association
  • and many more.

Where can I get additional information on food irradiation?

  • Visit the websites listed or call the Center for Consumer Research at the University of California, Davis, for more information: (530) 752-2774. At each site, click on "food irradiation", or type "irradiation" in the search box.