The small amount of energy that does not pass through the food is retained as heat. This energy is able to kill bacteria, molds, insects, and parasites. The safety of food irradiation has been researched for the past 50 years and approval for irradiation of certain food items started in the 1960 s. Herbs and spices have been irradiated since the 1980 s. There are many advantages to food irradiation. It can replace many chemicals, currently used for this purpose, that further pollute our air and water.
Irradiation also extends the shelf life of certain foods by preventing spoilage.
Ultimately this leads to cost savings for the consumer. Animal research over the past 40 years has failed to show any harmful effects from eating irradiated food. You can identify those foods which have been irradiated because they are required to carry an identifying label. Currently, foods that are irradiated in the US are herbs and spices, citrus fruits, tropical fruits, strawberries, tomatoes, mushrooms, potatoes, onions, and poultry. It is important to remember that irradiation does not eliminate the need for proper food handling and storage.