Sometime early next year the Department of Agriculture should issue final regulations for irradiating red meat, theoretically allowing consumers to eat their hamburger blood rare without risking infection from salmonella or, worse, deadly E. coli 0157:H7.
Although the use of gamma rays to zap pathogenic bacteria is a technology that has been available for several years, only recently has there been anything like a unified push by government and the food industry to implement it.
This year the Grocery Manufacturers Association, which represents food suppliers, and the Food Marketing Institute, a supermarket trade group, have joined the USDA in trying to persuade processors, retailers and shoppers that irradiation makes food safer.
More than 50 years of scientific research has shown that bombarding certain foods with low levels of radioactive ions is an effective way to kill potentially harmful organisms and at the same time extend the foods shelf life. But so far irradiation is used only sparingly, mostly in hospitals and for provisions eaten by astronauts. Only a few retail stores in the U.S. sell irradiated products, and only one facility is licensed to irradiate food (Food Technology Services Inc., in Mulberry, Fla.).
So the food industry now is joining scientists in a campaign to promote food irradiation.
“While not a solution to every food safety problem, irradiation is another weapon in the food-safety arsenal,” says C. Manley Molpus, president of the GMA. It’s “too beneficial for us not to use.”
Calling irradiation a “food-safety tool whose time has come,” Tim Hammonds, president of FMI, says: “We must make consumers an active part of this process. Food irradiation is not something we are going to do for consumers, but something we can only do with consumers.”
Hammonds and Molpus imply that acceptance is just a matter of educatingor persuading-the public. A FMI/GMA joint poll shows that 79 percent of consumers are “somewhat inclined” to buy food labeled thusly: “Irradiated to kill harmful bacteria.”
But others are not so certain that the required “radura” label (indicating a food has been irradiated) should become as common as the USDA Inspected stamp.
“If there are some foods that can be made safe only through irradiation, then maybe it should be considered in limited situations,” says Michael Jacobson, executive director of the Center for Science in the Public Interest, a consumer group in Washington, D.C. “But not across the board.”
Jacobson outlines several reasons to be cautious about food irradiation, none of them new.
Not least important, he says, is that irradiated food will be more expensive because of the costs of equipment and transporting the food to and from irradiation facilities. Another is that radioactive chemicals create a hazard for workers exposed to them. That risk increases as the process is extended to every supermarket chain: The wider the use of the technology, the more potential for poorly trained personnel and thus mistakes, he says.
“Third, the use of irradiation changes the vitamin levels in some foods, such as thiamin in pork. And while eating pork with less thiamin once in a while doesn’t present a health hazard, if it becomes pervasive, it could promote deficiencies.”
Also, irradiation alters the chemistry of the food, so that undetected or unanticipated chemicals possibly could be produced, Jacobson warns. These chemicals-sometimes called radiolytic products-could be dangerous to some individuals.
“Lastly, we feel that people want clean safe food, not dirty safe food,” Jacobson says. “While the food industry will reassure us till the cows come home that they wouldn’t use the irradiation technology to cover up dirty food practices, their record is not completely believable.”
Few scientists concur with CSPI’s outlook, though.
“I am very disappointed that groups who say they are working to protect consumers aren’t demanding irradiation of foods,” says Christine Bruhn, professor of food science and director of the Center for Consumer Research at the University of California, Davis.
“The fact is that irradiation is the only technology that can assure a food is free of pathogens.”
Robert Grodner, professor of food science at Louisiana State University in Baton Rouge who has been studying food irradiation for four decades, says he has heard the “dirty food” objection to irradiation “for umpteen years.”
“Irradiation cannot make bad food good,” Grodner says. “It’s a process that takes the best possible food at the end of the line and then irradiates it to make it cleaner.”
Grodner, who is an adviser to the FDA on irradiation, says the question of whether widespread use of irradiation technology will present a safety hazard is valid.
“But this is not a technology that will be loosed on the retail level,” he says. “Although several facilities irradiate medical supplies, horsemeat and some spices, there is only one plant in the country now that is permitted to irradiate commercial foodstuffs. … It is not something we are going to see in every supermarket.”
The question of undetected radiolytic products also has been raised for years, he says.
“The fact is that we haven’t yet found anything (in irradiated food) we can’t identify, and we haven’t found anything that’s not found elsewhere, something you couldn’t get if you stayed out in the sun too long, for instance.”
So why has there been such reluctance to bring irradiated food into the mainstream?
According to Bruhn, marketers often say, ” `We will offer it when the public asks for it.’ But the public doesn’t ask for technology. They don’t say, `Give me steam pasteurization.’ What they ask for is safe food.”
Companies also worry about their corporate image, she says. If a chicken producer suddenly starts selling irradiated chicken labeled as safe from bacterial contamination, what does that say about the company’s non-irradiated chicken, or about what the company was doing before?
Reinforced by their consumer survey, Molpus and Hammonds believe irradiation will be introduced to the public in an orderly, affordable fashion over time.
For Bruhn it cannot happen soon enough. Recent tests published in Consumer Reports show that despite efforts by processors to control bacteria in chicken, about 70 percent still are contaminated with campylobacter and salmonella, the leading causes of food poisoning nationwide. “This is a serious problem and irradiation is a rational way to solve it,” she says.
Jacobson says he is more interested in alternative ways to control bacterial development, such as feeding cattle a different diet to alter their intestinal acid levels. That can inhibit the growth of pathogens, as can infecting young animals with beneficial bacteria to compete with more dangerous varieties. These kinds of solutions are much less radical than wholesale zapping of the food supply, he says.
HOW TO IRRADIATE A STEAK
Packaged foodstuffs-fresh or frozen-are sent past a radioactive source such as cobalt 60 or cesium that bombards them with gamma rays. The length of time they are bombarded determines the “dose.”
Low-dose radiation (less than 1 kilogray) will kill insects on fruit and grain and can kill Trichinella in pork.
Medium dose (1 to 10 kilograys) will kill most bacteria that cause foodborne illness and spoilage. Doses of 1.5 to 3 kilograys are used on poultry.
Higher doses are used to sterilize meat and to decontaminate spices and herbs.
One kilogray raises the temperature of the irradiated product slightly more than 0.4 degree Fahrenheit. It leaves no residue in the treated product.
Nevertheless it is potent energy, equal to about 1 million chest x-rays and more than one and a half times the dose deemed lethal to humans.
READY FOR IRRADIATION
Although irradiation of some foods has been approved in this country since the early 1960s, the only people who eat it regularly are astronauts in orbit and some hospital patients with weakened immune systems.
Here are the foods currently approved for irradiation by the Food and Drug Administration, though few undergo it routinely.
– Wheat and flour, approved in 1963 to control insect infestation.
– White potatoes, approved in 1964 to inhibit sprouting.
– Herbs and spices, approved variously from 1983 through 1986 to kill insects and microorganisms.
– Pork, approved in 1985 to control Trichinella spiralis, the cause of trichinosis.
– Fresh fruits, vegetables and grains, approved in 1986 to control insects, sprouting and ripening.
– Packaged poultry, approved in 1990 and 1992 to kill salmonella, campylobacter and other bacteria.
– Poultry feed, approved in 1995 to eliminate salmonella.
– Red meat, approved in 1997 to eliminate E. coli 0157:H7, salmonella and other pathogens in ground meats (USDA still needs to approve regulations).
