Academic Integrity Exercise 1
Food Irradiation: The Fears, the Facts by Mary Ann Hawkins
Early this year (1992), when the first irradiation plant in the U.S. designed to process food sent a truckload of irradiated strawberries to market, local television was on the scene and an activist group picketed. The sale of the berries was viewed by many as an important test of whether or not consumers would buy irradiated food. Did they? Yes; irradiated berries sold as well as nonirradiated ones. Irradiation, a controversial food-processing technology currently used in about 20 countries around the world, was first approved on a limited basis by the Food and Drug Administration (FDA) almost 30 years ago. It is endorsed as safe by the World Health Organization and many in the scientific community.
There is also a small but vocal opposition to irradiation: antinuclear activists, some scientist who say more research is needed and those who think benefits might be offset by safety risks that would be posed by large numbers of irradiation facilities around the country. To date, at least three states have placed a temporary ban on the sale of irradiated food in response to consumer concerns.
Why irradiate? Irradiation at the levels used on food kills harmful organisms, such as salmonella in chicken. It can also kill insects in food, halt the sprouting of onions and potatoes and extend the shelf life of perishable fruits such as berries. Proponents hail irradiation as a major food-safety breakthrough. Food poisoning, which irradiation could help control, costs billions of dollars each year in medical bills and lost productivity. Some say irradiation could also make a dent in the amount of food lost to waste or spoilage.
How is irradiation done? Food is moved into a thick-walled room and exposed for several minutes to a strong dose of ionizing radiation, usually generated by the radioactive metal cobalt-60. When radiation passes through food, some molecular bonds are broken and new compounds form. An FDA panel that studied these new compounds in 1980 found that approximately 90 percent of them also occur in foods that have not been irradiated.
"But what about the other 10%" asks J.J. Steinberg, M.D., associate professor of pathology, radiation biology and oncology at Albert Einstein College of Medicine in New York. "Some compounds that occur through radiation are unique and not naturally occurring." Some are mutagenic and may increase cancer risk, he says. "The risk is probably small, but to say there is not risk is foolish." Others disagree: "The mutagens in irradiated food are nothing more than what you find in food anyway," counters Sanford Miller, M.D., dean of the graduate school at the University of Texas Health Science Center in San Antonio.
When foods are irradiated, some nutrients are lost. But every form of foodprocessing caused nutrient loss, says Manfred Kroger, Ph.D., professor of food science at Pennsylvania State University in University Park: "When you cook carrots on the stove, you destroy one third to one half of the vitamins. When milk is pasteurized, it loses vitamin C, thiamin and riboflavin. The nutrient loss that occurs with irradiation at the levels approved here is probably comparable to that which occurs through pasteurization."
Possible benefits, alternatives: If the technology does become accepted and widely used, irradiation could reduce food poisoning and provide an alternative to certain postharvest pesticides and chemicals. If new uses are approved, irradiation could be used to kill salmonella in eggs and bacteria and parasites in fish and shellfish. Benefits aside, "It's unfortunate that more use has not been made of the technology that irradiates food without using radioactive materials," says Dr. Miller. "You could accomplish the same thing using other electromagnetic energy--basically a huge X-ray machine. When the switch goes off, the power goes off. It's easier and safer."
Do we really need irradiation? "No, we don't really need it," says Dr. Kroger. "But when there is a new process that will have a potential benefit, I say why not use it--if it provides another choice in the market place? And there will be a choice because food will be labeled. Some more conservative people would prefer to wait ten years or so until more is known. But if it is properly done, no harm will come to operators or to the food or to consumers."