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The four-month-long, nationwide salmonella outbreak from peanut butter—coming on the heels of other, widespread food-borne illnesses—raises the question: Why not just zap all of our food with radiation to destroy contaminants?
The U.S. Food and Drug Administration (FDA) last summer okayed irradiation to destroy pathogens in fresh iceberg lettuce and spinach in the wake of an Escherichia coli (E. coli) outbreak traced to the latter in 2006. Since the early 1980s, irradiation has also been approved for that same purpose in meats as well as to both extend the shelf life of and kill insects in fruits, veggies and spices.
But radiation isn't commonly used to treat most foodstuffs in the U.S. because of cost, consumer wariness and the worries of some about its long-term safety. Food & Water Watch (FWW), a Washington, D.C.–based advocacy group, frowns on the process, which it says degrades the nutritional value of foods and has the potential to mask but not remedy unsanitary conditions at plants that led to it in the first place.
We asked Sam Beattie, a food safety extension specialist at Iowa State University in Ames, to fill us in on the controversial process and why it hasn't been used more often, especially in light of the recent deadly outbreaks. There is an irradiation facility at the university, but it's used only for studies and Beattie, a microbiologist, has no affiliation with companies that make irradiation devices or zap their food.
[An edited transcript of the interview follows.]
What is food irradiation, and how does it work?
Irradiation is done by exposing food or bacterium to a dose of ionizing radiation, which disrupts the DNA or protein of pathogenic bacteria that make people ill.
When we talk about the sources for irradiation, we're looking at two major ones: radioactive elements—like cobalt 60—and the electron beam, or e-beam. Cobalt 60 is an isotope, or a traceable radioactive version of the element, that emits the type of radiation called gamma rays, whereas the e-beam is an electron-based radiation source. We also are experimenting now with x-rays, which are generated from an electron beam hitting a piece of metal, as a potentially new technology for irradiating food
The potential problems of the irradiation processes are fairly limited. As cobalt decays, it becomes less effective, so you have to monitor that. E-beams don't penetrate as deeply as cobalt, so you have to irradiate less of a food at a time. And generating x-rays takes an extra step, so it may not be as efficient as e-beam.
Cobalt 60 has historical precedence with food. It's been used for a long time with meats, fruits and vegetables. It is a safe source: When it decays, it becomes a stable, less radioactive element — in this case nickel, so disposing of it is less of a problem than with isotopes used at, say, nuclear plants. And there is no direct contact between the cobalt and the food or its packaging.
How long does it take to zap bugs in food?
It depends on the kind of radiation you're using. Cobalt 60 is a lower dose rate, so it takes longer—a minutes type of exposure. E-beam is a more intense, higher dose rate and we're looking at seconds.
Which foods is irradiation most used on?
Among fresh produce, the FDA has only approved irradiation to reduce food-borne illness in leaf spinach and iceberg lettuce. We're not exactly sure why only those two, because there's very little difference between cut greens when it comes to whether or not they turn to mush under an e-beam at the approved levels.
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15 Comments
Add CommentI, for one, do NOT want my food irradiated. If we eat locally produced food that is raised with cleanliness this problem would not arise. We really don't know how irradiation will affect our health way down the line.
Reply | Report Abuse | Link to thisWanting to irradiate our foods for longer shelf life and because they don't want to clean up their act smacks of corporate greed once again.
I see farmworkers harvesting in fields with nothing more than a moveable portapotty nearby. Handwashing facilities should be supplied and handwashing enforced by growers or people hired to supervise harvesting by hand. Washing in packing faciities can't aways remove fecal bacteria.
Reply | Report Abuse | Link to thisuser659callifornia, I agree! Here in Oregon, I picked strawberries as a kid and I noticed that most of the workers didn't have the best sanitary standards! If people knew that the guy that picked their fruit or vegetables had gone to the bathroom and not washed his hands, would they be fine knowing they just rinsed their fruit in a bit of cold water?
Reply | Report Abuse | Link to thisIrraditation would prevent many deaths and countless cases of sickness, but people have such an irrational fear of anything "radioactive" that they'd rather play Russian Roulette with their food than have it irradiated!
PLEASE IRRADIATE MY food! I have zero issue with this and I've been an advocate of this since I first heard about this in the 80's. People have died because of germs in the food supply. This would have already saved lives. If this were a clinical trial it would be unethical to not irradiate food at this point!
Reply | Report Abuse | Link to thisI know radiation sounds like to boogie man but in this application it's not.
Workers in the field are not the only issue. The last outbreak of salmonella was attributed to a water supply.
Reply | Report Abuse | Link to thisI 100% agree that the best solution is a clean environment. However realistically speaking that aint gona happen! So irradiation is a good answer to mass produced food,
Urania: You are living in an elitist fantasy world. Locally-grown food is impossible for the mass population. You didn't mention that you want to pay a LOT more for your food, which is what will happen if quality is increased (unless you hold a paranoid belief that 'other' people intentionally produce contaminated food because they don't care [like you, of course, do] or are just plain mean spirited). I've personally met this person Corp. Greed. Do you know where he lives?
Reply | Report Abuse | Link to thisIrradiate all of it...especially milk and ganges beef! Remember that irradiation never makes anything radioactive...unless the food is wound thru a neutron flux. Uhmm tasty!
Reply | Report Abuse | Link to thisI am also for food irradation. However I feel there should be lable showing the food was processed in this way. This has made Genticaly modified foods a problem because people do not understand the process involoved.
Reply | Report Abuse | Link to thisFor food irradation you use a radio active source to destroy all harmful parasite bactreria fungie etc. Nothing can survie the radation. The food is safe to eat and there is no lingering radioactivity. The food is much much safer to eat and is easer to handle. I used to work in the food processing environment and microbacterial buildup is always a issue in food processing equiptment. Souds like the people got sloppy in washing the equiptment and the inspections failed to catch it .
I am surprized there is no radom sampling done as part of a quality control. If random samples were pulled sooner or latter the bad batch would have shown up.
While irradiation can reduce contamination by viable microbes, I am concerned that processors will rely on it and abandon the few contamination-mitigating practices that they currently use.
Reply | Report Abuse | Link to thisI think irradiation is great. It is especially valuable for organicly grown foods, where disease carrying manures are used for fertilizer, where Pateurization is avoided, and where preservatives are left out. All three of these situation increase the danger of food poisonings. I support buying locally grown foods, but they aren't saintly when it comes to diseases.
Reply | Report Abuse | Link to thisSCI-AM, I would appreciate better editing on your part when it comes to scientific names. Genera, such as Salmonella, should always be capitalized. Species, such as the coli of E. coli, should always be in lower case. Thank-you.
Reply | Report Abuse | Link to thisI'm older, now 60, and am having trouble with my balance in the dark house at night. Please irradiate my food!
Reply | Report Abuse | Link to thisI am very comfortable with the idea of being my own night-light!
This is the result of overdoing the processing of foods. Yore, no such sickness, how come it exist now? The answer is just simple...we tend to overdo everything and failed to see the possible negative output. But its not yet too late.
Reply | Report Abuse | Link to thisI would like to know what the studies are that show 2-Alkylcyclobutanones (2-ACBs) are safe. The research I read found it to be a mutagen, carcinogenic and to promote tumor growth.
Reply | Report Abuse | Link to this# Raul, F. et al. "Food-Borne Radiolytic Compounds (2-alkylcyclobutanones) May Promote Experimental Colon Carcinogenesis". Nutrition and Cancer, 44(2): 188-191, 2002.
# Delincee, H. and Pool-Zobel, B. "Genotoxic Properties of 2-dodecylcyclobutanone, a Compound Formed on Irradiation of Food Containing Fat". Radiation Physics and Chemistry, 52:39-42, 1998.
I wonder if it may be the causative factor in the rise in colon and prostate cancers.
Irradiation is expensive and adds cost to food. It changes the fats and nutritional content. Sure cooking does to, but we are not talking about replacing cooking with irradiation. This means the end product is even more nutritionally deficient.
Irradiation plants expose workers and the environment to harmful radiation. All we are doing is exchanging one poison for another.
If irradiation of food stuffs became common, could we use radioactive waste for a source of radiation? If so, could it reduce the problem waste products?
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