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Ned Potter is the science correspondent for ABC's "World News with Charles Gibson." He has reported on such topics as space exploration, the human genome and climate change.

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Too Hot to Touch

April 11, 2008 4:06 PM

Irridate_080411_main You can wash your lettuce until there's nothing left of it.  But nothing we routinely do in America -- not even rinsing produce in chlorine disinfectants -- will get rid of all the bacteria that cause food poisoning. 

That's the view, at least of a group of Agriculture Department researchers.  They say the most effective solution they see is irradiation -- exposing food to a beam of charged particles.  Brendan A. Niemira, from the USDA's Agricultural Research Service near Philadelphia, was on a team making a presentation yesterday in New Orleans to the American Chemical Society, saying they found irradiation killed 99.9 percent of the E. coli found in spinach and lettuce leaves.  Conventional rinsing, they said, never got past the surface, and were almost useless when bacteria congregated in "biofilms," colonies where they form protective outside layers.

Irradiation is one of those subjects that's festered for years; witness this decade-old BACKGROUNDER from the University of Georgia.  Niemira's colleague Ben Miller, of the University of Rochester, told Dr. Diane Kang of our Medical Unit, "Irradiation has a bad rep with the public," but he called it "great" -- a safe way to remove contaminants from fresh food.  40 other countries have approved its use, and the FDA allows limited use on meats.

The CDC has some background info HERE; the folks who wrote it are all for it.  They say it kills pathogens, and does not make your food radioactive.

But what do you think of when you think of radiation?  Cancer?  Genetic damage?  Unknowable risks?  The FDA has been in the process of reviewing food irradiation for broader use, and has provoked responses such as THIS one last year from the Center for Food Safety: "Radiation can do strange things to food, by creating substances called 'unique radiolytic products.'  These irradiation byproducts include a variety of mutagens -- substances that can cause gene mutations, polyploidy (an abnormal condition in which cells contain more than two sets of chromosomes), chromosome aberrations (often associated with cancerous cells), and dominant lethal mutations (a change in a cell that prevents it from reproducing) in human cells. Making matters worse, many mutagens are also carcinogens."

Believers insist it's safe.  Doubters are not persuaded.  In the meantime, you have to eat.

(Above: the FDA's current symbol, required on food that's been irradiated.  How often have you seen it?)

April 11, 2008 | Permalink | Share | User Comments (17)

User Comments

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Can't say I have ever seen the Irradiation Label.

The thing I wonder about is whether the irradiation is producing more and/or more toxic food than we have now. When we find heavy metals and hormones etc in both our food and our water one has to wonder which is the bigger problem.

Ideally we want natural food but it seems that in order to eat such food one needs an immune system that is 100% complete.

Posted by: Andy Clark | Apr 11, 2008 4:43:13 PM

I dont trust it and am growing my own veggies and this year. I hope more people do because like so many in this country, already battled with cancer, and Im only 35. So many things making us sick,, but theres never real focus on the CAUSES of all these cancers,, (except smoking) just how to 'fix' the problem with slow painful poisoning. Time to go back to more natural living folks,, or pay the price.

Posted by: Jennifer | Apr 11, 2008 4:57:43 PM

We live in a world that's continuously getting more and more steril. We have no immunity to any disease, or any real defenses for said diseases. I for one just eat whatever. I don't even wash any of the foods I eat. I also make it a point to expose myself to germs and pathogens on a regular basis. I do this to get my body used to it, and build up the anti-bodies for said germs and pathogens. As a result, I've been devoid of illness my entire life. I can kick a cold within 24 hours. It takes everyone I know at least 2 to 3 days. Flu? No problem, 1, maybe 2 days. Anything else is gone with in a day or two. And they even don't bother me too much, I can go on with my daily life just like normal, with minimal disturbance. So no, I don't want this. Let me have my germs. This will protect and keep me healthy in the short term, but hamr me over time from lack of germs. People need to realize the sterility and fear of germs is not a good thing. Bring them on I say.

Posted by: Lawrence | Apr 11, 2008 5:18:36 PM

although i grow most of my veggies and prepare for winter by preserving/canning/dehydrating etc. when i find myself purchasing non-organic produce i rinse with hydrogen peroxide or better yet with diluted grape fruit seed extract.

Posted by: sonia trevino | Apr 11, 2008 5:55:16 PM

Since when do we need to have our food germ free? In that case, we still get germs from breathing, from the plate and from utensils so it is still not a solution. It is just an excuse to be able to sell us dung contaminated food. If that is the case, it would be "OK" to sell a package of a vegetable with an irradiated dead rat in it or something similar.

Posted by: PQQAm | Apr 11, 2008 6:16:44 PM

We have to maintain our food quality. An irradiated orange is no longer an orange after irradiation because its chemical composition has been altered. It is not good food quality and it, for sure, is not organic. It is just an excuse to sell previously contaminated food. Expired food could be used for fertilizer or compost.

Posted by: PQQAm | Apr 11, 2008 6:28:04 PM

"CDC estimates that 76 million people get sick, more than 300,000 are hospitalized, and 5,000 Americans die each year from foodborne illness."

All killed by insane paranoia.

Posted by: Neo Politicus | Apr 12, 2008 3:20:50 AM

I have been in favor of food irradiation for years. If it's good enough for NASA, it's good enough for me.

Where does this "Center for Food Safety" get it's information? I don't believe that any real scientific study has come to the same conclusion as these people. Where is their proof?

Food irradiation is already proven to be effective. If all foods were treated there would be no more microbe contaminated food poisoning outbreaks that seem to increase every year. There would be no more recalls where millions of pounds of meat and produce are discarded because of contamination in some small part of the product, saving millions of dollars. With so much starvation in the world, it's a sin to throw out precious food because of a scare.

People of America, stop listening to these self-serving nay-sayers on food irradiation. They don't know what they are talking about and are lying to you. Would you rather have safe, healthy food or continue listening to these idiots and charlatans and throwing out your increasingly expensive foods several times a year?

Posted by: BG | Apr 12, 2008 12:34:53 PM

PQQAm,
Who told you that "An irradiated orange is no longer an orange after irradiation because its chemical composition has been altered"? Where is your proof?

People, an irradiated orange is simply a germ and mold free orange. Nothing more, nothing less. It does not change molecularly. It does not become a "frankenfruit", although it will last longer than a non-irradiated orange. What a bummer... food with longer shelf lives! Who wants that?

All irradiation does is kills pathogens. IT DOES NOT CHANGE FOOD. In case you missed that, I'll repeat: IT DOES NOT CHANGE FOOD.

And yes, there IS scientific evidence to back that statement up, unlike what PQQAm and others would have you believe.

Posted by: BG | Apr 12, 2008 12:47:34 PM

There is a simple solution. Allow irradiation, but require a label. If the majority of people want it, they will sell more irradiated food. Otherwise, they will sell more non-irradiated food. Either way, people can choose for themselves. There is no need to argue.

Posted by: Mark | Apr 12, 2008 5:26:23 PM

Mark, your comment would seem like wisdom, but such a common-sense, market based idea in the public arena, especially having anything to do with radiation, may be shouted down by enviro-do-gooders.

Posted by: Todd | Apr 13, 2008 1:51:23 PM

If it tastes different, which it does, the chemical composition has been altered. Even microwave alters the chemical composition because the consistency is altered.

Whether or not this causes harm is another issue but the chemical composition is altered. It has to do with food quality. Irradiated food cannot be called organic food. I don't like food that does not taste like it was just picked.

I was raised eating fresh fruit right off the trees. I have a real problem with eating any fruit from the supermarket. It is horrible.

Later on down the line, the scientists will realize that I was right about the food quality. It is better to eat Guavas with worms in it than to eat irradiated food.

Babies become acclimated to a region by putting everything into their mouths. They might have the constant runs for a while but they become acclimated to the region.

I went to Europe and if a grain of sand or even a bit of dust got in my mouth, I would get the runs because I was not acclimated to the region.

Sterile is good for the operating room but it is not good for the food that we eat because our immune system needs to be able to protect us. It is like indoor plants that fall over because there are no elements of wind and rain to make them strong.

Our liver matches the viruses that we encounter with the cure. This is a process that is "learned" by our immune system.

How do you expect our digestive system acquire "good bacteria" if everything that we eat is sterile?

People die when their immune systems don't work well enough just like the trees that fell over in the biosphere.

Posted by: PQQAm | Apr 13, 2008 3:14:40 PM

People build up a resistance to animal and insect bites. The same is true with illnesses. People have weak immune systems when they are not exposed to things.

It would be better to study targeted nutrition that helps boost the body's immune system with simple things like coffee, chocolate, cinnamon and other herbs, supplements, nuts and berries.

I laugh at Florida fire ants and mosquitoes when they bit me because I am used to South American fire ants and mosquitoes.

Posted by: PQQAm | Apr 13, 2008 3:32:28 PM

So, PQQAm, you've eaten two oranges from the same tree, picked at the same time, one irradiated, the other not and you tasted a difference? If that is really true, I might tend to consider that more research is needed but I don't really believe it.

Sure, microwaves change chemical composition. They do so the same way as fire, by the action of heat energy, not the microwave radiation. Microwaves cause molecules to vibrate, generating heat. It's this heat, not the microwave energy itself, that cooks the food. Cooked food is indeed chemically different than raw food, whether it's cooked by boiling, frying, roasting, or grilling on an open fire. Just like how wood and charcoal are chemically different. The reason microwaved meat is not that appealing is because it lacks the browning and charring that comes from direct heat, be that from the broiler flame or frying pan, not because of some molecular mutation caused by the microwaves.

Regarding the need for exposure to germs to build the immune system, you all have a good point but I don't think that's really the issue here. Although food irradiation kills the "good germs" along with the bad, the rest of our environment is not sterile and we get plenty of other exposure to microbes. We don't have to ingest salmonella, listeria, or e. coli in order to develop a strong immune system. I'd rather eat irradiated food than worry that I could die from my next hamburger.

Posted by: BG | Apr 13, 2008 5:34:16 PM

Radiation in large enough doses to kill all the pathogens DOES change the appearance and taste of delicate food. IOW, yes you can tell the difference between unradiated and radiated food. IMHO, that's the real reason that, for decades, radiation has been confined to foods whose appearance doesn't change, like spices and nuts.

Here's what the CDC says:

However, not all foods are suitable for irradiation. For example, oysters and other raw shellfish can be irradiated, but the shelf life and quality decreases markedly because the live oyster inside the shell is also damaged or killed by the irradiation. Shell eggs can sometimes be contaminated on the insides with Salmonella. However, irradiation causes the egg whites to become milky and more liquid, which means it looks like an older egg, and may not serve as well in some recipes.

For irradiation to be effective, the food that is to be irradiated already needs to be clean. The more initial contamination there is, the higher dose of irradiation it would take to eliminate possible pathogens, and the greater the change in the taste and quality of the food. The protection of irradiation will be overcome if the contamination levels are too high.

Posted by: googler | Apr 13, 2008 6:02:31 PM

I just knew someone would say something about the microwaves cooking the food.

The point is that the cooked food from the microwave is chemically different than food cooked with fire or heat. I know that I didn't say that but I thought that you would be able to figure it out.

Posted by: PQQAm | Apr 13, 2008 9:01:43 PM

Why do scientists belive in the "big boom" therory and not god?

Posted by: person | Apr 28, 2008 11:59:37 AM

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