Shortly after the tragic events of September 11, 2001, concern about the possible use of anthrax to terrorize Americans turned to a grim reality. Letters spreading anthrax, illness, and immeasurable anxiety were delivered to an already stressed U.S. population. With the U.S. Postal Service identified as a launching pad for the infection of citizens, public health workers and bioterrorism experts evaluated viable methods of controlling this very dangerous situation.
Safeguarding the Mail
With offices, mailrooms, and entire post offices closed for decontamination, the U.S. Postal Service turned to irradiation to kill bacteria and sanitize the mail. Irradiation, defined as the application of radiation, especially for therapeutic purposes, is a relatively obscure technology that is used worldwide as a tool to help researchers in the scientific, medical, and environmental fields. It has now been thrust to center stage and is being used in a new and practical way-to safeguard the mail. This new attention to irradiation has generated consumer interest in learning more about irradiation and its many uses.
Radiation, Health, and the World Around Us
Our world is naturally radioactive. Our bodies contain naturally occurring radioactive substances, and cosmic radiation is present in the air and space around us and in both natural and artificial substances that we consume each day.
Until the invention of the X-ray tube in 1895, the only radiation in existence was natural radiation. One year later in 1896, natural radioactivity was discovered and was used for medical and research purposes until 1934, when the first man-made radioactive materials were produced.
Despite irradiation's many positive contributions to society, knowledge and understanding of irradiation are far from widespread, leading to questions about its safety. Some concern is understandable; but, in the case of the judicious use of radiation, the many benefits to society far outweigh the risks.
Irradiation technology is already being used in the United States on a daily basis to protect consumers, for example, to sterilize medical equipment (surgical gloves and bandages), in hygiene (tampons), and in products' packaging (plastic containers for sealed, individual-size cream containers). Now it is being used to disinfect the mail.
Based on years of scientific research, irradiation (in much smaller doses than that used to safeguard the mail) has also been approved for use to destroy illness-inducing bacteria in poultry and meat and is used to make germ-free herbs and spices.
Food Irradiation 101
Food irradiation, simply speaking, is the treatment of food with a certain type of energy. The irradiation process involves exposure of the food, either packaged or in bulk, to carefully controlled amounts of ionizing radiation for a prescribed period of time to achieve specific objectives.
Food irradiation can prevent the growth of microorganisms that cause food spoilage, such as bacteria and molds. It can also lengthen the period of ripeness of fruits and vegetables. This technology can prolong the freshness of many foods and prevent certain foodborne illnesses.
Food has been safely irradiated in the United States for over 30 years, and more than 40 countries around the world approve the process. In the United States, the Food and Drug Administration has approved the use of food irradiation for fresh meat (including ground beef, pork, lamb, and poultry), fresh fruits and vegetables, seeds for sprouting, shell eggs and spices.
How Does Food Irradiation Work?
Because food irradiation kills the spoilage- and disease-causing bacteria in food without significantly raising the temperature of the food, it is often called "cold pasteurization." Conventional heat pasteurization, which eliminates bacteria in liquids such as milk, beer, and wine, is a widely accepted and proven method of enhancing the safety of certain foods and beverages. However, the heat pasteurization of "solid" foods, such as meat and produce is not practical because it changes the products to a cooked form rather than a raw form.
During the food irradiation process, the food passes through an enclosed irradiation chamber where it is exposed for a precise period of time to a source of ionizing energy. One of three types of ionizing energy can be used: gamma rays, X-rays, or electron beams. All three types of ionizing energy have the same ability to inactivate spoilage- and disease-causing microorganisms without causing any harmful changes to the food. The food remains uncooked and completely free of any radiation residues.
Why Use Food Irradiation?
The most significant public health benefit of food irradiation is that it stops the spread of foodborne disease by dramatically reducing or eliminating the number of disease-causing bacteria and other harmful organisms that threaten our food supply and us. Most consumers have heard of outbreaks of foodborne illnesses caused by such organisms as Salmonella, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, Campylobacter jejuni and Toxoplasma gondii. Food irradiation could have greatly reduced or completely prevented many of these outbreaks.
When food is irradiated, the irradiation process breaks down the DNA molecules of the harmful organisms. An added advantage is that food can be irradiated in its final packaging-fresh or frozen-which prevents the possibility of contamination in the distribution system, at the store, or even in the home, before the package is opened.
Increased Public Confidence in Irradiation for Food
Consumer research has shown that when people learn why food is irradiated-for safety and other public health benefits-their attitudes change from concern to support for this technology that can provide such important public health benefits. Continued consumer education is necessary to further increase public understanding of food irradiation.
At the same time, consumers should know and accept that food irradiation is not a magic bullet that absolves them of their responsibility to handle food safely. Irradiation cannot hide spoilage, nor can it prevent cross contamination with other foods during the preparation process in the restaurant, the food service arena, or the home. The basic rules of food safety still apply as shown above in the Fight BAC! tips.
Who Regulates Food Irradiation?
In the United States, the Food and Drug Administration, U.S. Department of Agriculture, U.S. Department of Defense, U.S. Army, and National Aeronautics and Space Administration are among the governmental organizations that either approve or establish guidelines for food irradiation.
Several of the organizations listed above as well as independent researchers in the fields of industrial radioactive materials transportation and plant worker safety have assessed the public safety of food irradiation. These tests have consistently concluded that workers in food irradiation plants as well as citizens in surrounding communities face a very minimal risk of contamination with radioactivity. The safety record of this technology is excellent.
All irradiated foods in the United States and other countries where food irradiation technology is approved for use are required to be labeled with the international symbol for irradiation, the radura, and statements such as "Treated with Radiation" or "Treated by Irradiation." The U.S. government has also recently approved packaging with the statement, "Irradiated for Food Safety."
Strict regulations and ongoing food irradiation research protect consumers from the risks that may arise from the processing, storage, handling, and consumption of irradiated foods. In fact, the World Health Organization, the renowned global authority on public health states, "Food irradiation is a thoroughly tested process and when established guidelines and procedures are followed, it can help ensure a safer and more plentiful food supply."
Food irradiation has the ability to provide benefits to consumers by improving the safety of the worldwide food supply. This important and rapidly evolving field is covered in greater depth in a new IFIC brochure, developed in partnership with the International Consultative Group on Food Irradiation, an intra-governmental body with the goal of providing governments with scientifically accurate information on food irradiation technology. Food Irradiation: A Global Food Safety Tool will be available on-line in early 2002 at http://ific.org.
Quick Questions to Ask
When reading or viewing reports of health- and nutrition-related studies, consumers should ask themselves the following questions. A well-reported news story should contain the answers.
- What type of study is being reported?
- How many people were studied and for how long?
- Was the study published in a peer-reviewed journal?
- Do the study author's credentials indicate nutrition expertise?
- How does the study relate to the context of the larger body of evidence on this subject?
- What are the actual versus relative numbers?
Fight Bac Tips
When preparing meals for yourself or your family, it is important to remember these four simple steps to keep your food safe from harmful bacteria. It's as simple as 1-2-3-4.
- Clean: Wash hands and surfaces often
- Separate: Don't allow cross contamination between raw and cooked foods
- Cook: Cook to proper temperatures
- Chill: Refrigerate promptly
Resources for more information
