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Food Irradiation
What You Need to Know
Food irradiation (the application of ionizing radiation to food) is a technology that improves the safety and extends theshelf life of foods by reducing or eliminating microorganisms and insects. Like pasteurizing milk and canning fruits andvegetables, irradiation can make food safer for the consumer.
The Food and Drug Administration (FDA) isresponsible for regulating the sources of radiationthat are used to irradiate food. FDA approves asource of radiation for use on foods only after it hasdetermined that irradiating the food is safe.

Why Irradiate Food?

Debunking Irradiation Myths
Irradiation does not make foods radioactive, compromise
nutritional quality, or noticeably change the taste, texture, orappearance of food. In fact, any changes made by irradiation
are so minimal that it is not easy to tell if a food has been
irradiated.

Irradiation can serve many purposes.
•Prevention of Foodborne Illness – irradiation
can be used to effectively eliminate organismsthat cause foodborne illness, such as Salmonella
and Escherichia coli (E. coli).

•

Preservation – irradiation can be used to destroy
or inactivate organisms that cause spoilage anddecomposition and extend the shelf life of foods.

•Control of Insects – irradiation can be used todestroy insects in or on tropical fruits imported
into the United States. Irradiation also decreases
the need for other pest-control practices that may
harm the fruit.

•Delay of Sprouting and Ripening – irradiation
can be used to inhibit sprouting (e.g., potatoes)
and delay ripening of fruit to increase longevity.

•Sterilization – irradiation can be used tosterilize foods, which can then be stored foryears without refrigeration. Sterilized foods
are useful in hospitals for patients with severely
impaired immune systems, such as patientswith AIDS or undergoing chemotherapy. Foods
that are sterilized by irradiation are exposed to
substantially higher levels of treatment than thoseapproved for general use.

How Is Food Irradiated?
There are three sources of radiation approved for use on foods.
•Gamma rays are emitted from radioactive forms of the element
cobalt (Cobalt 60) or of the element cesium (Cesium 137).
Gamma radiation is used routinely to sterilize medical, dental
and household products and is also used for the radiation
treatment of cancer.

•X-rays are produced by reflecting a high-energy stream ofelectrons off a target substance (usually one of the heavy metals)
into food. X-rays are also widely used in medicine and industry
to produce images of internal structures.

•Electron beam (or e-beam) is similar to X-rays and is a streamof high-energy electrons propelled from an electron accelerator
into food.

Did you know?

National Aeronautics and Space
Administration (NASA) astronauts
eat meat that has been sterilizedby irradiation to avoid getting
foodborne illnesses when they flyin space.

June 20111

Is Irradiated Food Safe to Eat?

What Foods Have Been
FDA has evaluated the safety of irradiated food for more Approved for Irradiation?
than thirty years and has found the process to be safe. The
World Health Organization (WHO), the Centers for Disease
Control and Prevention (CDC) and the U.S. Departmentof Agriculture (USDA) have also endorsed the safety ofirradiated food.

FDA has approved a variety of foods for irradiation in theUnited States including:
•••
••••
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Beef and Pork
Poultry
Molluscan Shellfish(e.g., oysters, clams, mussels, and scallops)
Shell Eggs
Fresh Fruits and Vegetables
Lettuce and Spinach
Spices and Seasonings
Seeds for Sprouting (e.g., for alfalfa sprouts)

How Will I Know if My Food Has Been Irradiated?
FDA requires that irradiated foods bear theinternational symbol for irradiation. Look for theRadura symbol along with the statement “Treatedwith radiation” or “Treated by irradiation” on
the food label. Bulk foods, such as fruits andvegetables, are required to be individually labeled
or to have a label next to the sale container. FDA
does not require that individual ingredients in
multi-ingredient foods (e.g., spices) be labeled.

It is important to remember that irradiation is not a
replacement for proper food-handling practices byproducers, processors and consumers. Irradiatedfoods need to be stored, handled and cooked in
the same way as non-irradiated foods, because
they could still become contaminated withdisease-causing organisms after irradiation if therules of basic food safety are not followed.

Everyone can practice safe food handling by following these four steps:

For more information, contact: The U.S. Food and Drug Administration Center for Food Safety and Applied Nutrition Food Information
Line at 1-888-SAFEFOOD (toll free), 10 AM to 4 PM ET, Monday through Friday. Or visit the FDA Web site at www.fda.gov

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