SGU Listener, Alex, recently sent me a question about the safety of irradiated food:

“Dr. Samuel Epstein, chair of the Cancer Prevention Coalition, is quoted as saying, “Every man, woman and child who takes a bite of irradiated food increases their chance of getting cancer. It is no exaggeration to say that our government has turned the American people into guinea pigs.” Is there any science to this? Am I irradiating my body by eating bread? Do irradiated bananas give me a double dose of dangerous death rays?”

This is another example of the general rule – for every safe and life-saving technology out there, there is a group of people fearmongering about its risks. Irradiating food is a completely safe and effective way to reduce the risk of food borne illness and contamination. It is an underutilized technology because of unwarranted fears.

Irradiated is not radioactive

Food treated with radiation is not radioactive itself. So you will not get any extra dose of radiation from consuming such food. Radiation has simply passed through it in order to kill bacteria and insects.

There are several methods used. The most common is to expose food to gamma radiation from a cesium or cobalt source. You can also use X-rays or an electron beam. These are all ionizing radiation, meaning that they are high energy enough to break chemical bonds. Inside cells the effects of radiation can create sufficient oxygen free radicals to kill the cell.

There is no way that you could tell from inspection or eating if a food has been irradiated or not – unless the food is obviously contaminated, with mold, for example, in which case it probably has not been irradiated.

There have been 40 years of studies and use of irradiated food, without any evidence of harm or any health risk. Some countries, such as Israel, make liberal use of irradiation for food safety, again without any problems emerging. The World Health Organization has reviewed hundreds of studies and concluded that irradiated food is safe.

Irradiated food is also nutritionally equivalent to non-irradiated food. There are some minor chemical reactions, but any resulting change in the amount of various chemicals is insignificant.

Effectiveness of irradiating food.

The purpose of irradiating food is to reduce contamination and thereby increase the safety and shelf life of the food. This is perhaps most useful in meat, which is at risk of bacterial contamination and a frequent source of food poisoning. Fresh or frozen meat can be safely irradiated without changing is other qualities. Such irradiation is characterized by the log of the amount of bacteria killed. A one log kill will reduce bacteria to 10%, a two log kill to 1%, etc. Different doses can be used for different purposes. Higher doses of radiation can be used to effectively sterilize the food, for special applications such as in the international space station (where long shelf life is essential) or for patients with compromised immune systems.

Right now in the US irradiation is approved from some fruits and vegetables, meats, shell fish, eggs, and spices. It isn’t used for food that have a high fat content, like milk or peanut butter, because fats do tend to chemically change from radiation, affecting their flavor.

Irradiation is likely underused in the US (other developed countries use it more) because of cost and consumer misinformation. Irradiating food also does not replace other food safety measures. Food can always be recontaminated after irradiation if it is not handled properly. But irradiation can be a highly effective method of protecting food – especially in certain vegetables, like lettuce and spinach, and in all meats. These foods are prone to E. coli and other bacterial contamination.

Even in the US, which has arguably the safety food supply in the world, food contamination is still a risk:

CDC estimates that each year roughly 1 in 6 Americans (or 48 million people) gets sick, 128,000 are hospitalized, and 3,000 die of foodborne diseases.

Anything that makes the food supply safer has the potential to reduce death and illness. This is even more true in countries with a higher rate of foodborne illness. Further, the extension of shelf life and reduction of food spoilage will make the food supply more efficient by reducing waste.

The bottom line is that food irradiation is a safe and effective method for reducing contamination in food, making food safer and extending shelf life, with minimal and insignificant changes in the food itself. It is not currently being optimally used primarily out of unwarranted fears.