This is the difference between low kinetic energy (top) and high kinetic energy (bottom), as illustrated in the 1956 Disney book Our Friend the Atom. It may be useful in visualizing some of the ideas presented in my recent feature on space radiation.

From Fresh Photons, a fantastic blog chock full of science pictures.

Space is full of radiation. It's impossible to escape. Imagine standing in the middle of a dust storm, with bits of gravel constantly swirling around you, whizzing by, pinging against your skin. That's what radiation is like in space. The problem is that, unlike a pebble or a speck of dirt, ionizing radiation doesn't bounce off human flesh. It goes right through, like a cannonball through the side of the building, leaving damage behind.

Last week, researchers at the University of Rochester Medical Center published a study that suggests long exposures to galactic cosmic radiation — like the kind astronauts might experience on a trip to Mars — could increase the risk of developing Alzheimer’s disease.

Reading stories about that paper made me curious. We've now been sending people into space for more than 50 years. We've been able to track a generation of astronauts as they aged and died and we're constantly monitoring the people who travel in space today. Research like what was done at the University of Rochester is conducted on lab animals, mice and rats. It's meant to help us prepare for the future. But what do we know about the past? How has radiation affected the people who have already been to space? How is it affecting the people who are there now?

There is one key difference between the astronauts of today and those of the future. That difference is the Earth, itself.

Galactic cosmic radiation — also called galactic cosmic rays — is the kind of radiation that researchers are most worried about. It's made up particles, bits and pieces of atoms that were probably flung off from the aftermath of supernovas. The majority of this radiation, roughly 90%, is made up protons ripped from atoms of hydrogen. These particles travel around the galaxy at almost the speed of light.

And then they hit the Earth. This planet has a couple of defense mechanisms that protect us here on the ground from the impact of galactic cosmic radiation. First, Earth's magnetic field both pushes away some of the particles and blocks others completely. Then, the particles that make it through that barrier start to encounter the atoms that make up our atmosphere.

If you drop a big tower made of Legos down the stairs it will break apart, losing more pieces every time it hits a new step. That's a lot like what happens to galactic cosmic radiation in our atmosphere. The particles collide with atoms and break apart, forming new particles. Those new particles hit something else and also break apart. At each step, the particles lose energy. They get a little slower, a little weaker. By the time they "come to a stop" at the ground, they aren't the galactic powerhouses they once were. It's still radiation. But it's much less dangerous radiation. Just like it would hurt a lot less to be hit with one Lego block, than with a whole tower of them.

All of the astronauts we've sent into space so far have, at least partially, benefited from Earth's protective barriers, Francis Cucinotta told me. He's the director of the NASA Space Radiobiology Program, the go-to guy for finding out how radiation hurts astronauts. He says, with the exception of Apollo flights to the Moon, the human presence in space has happened within the Earth's magnetic field. The International Space Station, for instance, is above the atmosphere, but still well inside the first line of defense. Our astronauts aren't exposed to the full force of galactic cosmic radiation.

They're also exposed to it for a relatively limited amount of time. The longest spaceflight ever lasted a little over a year. And that matters, because the damage from radiation is cumulative. You simply can't rack up as much risk on a six month jaunt to the ISS as you could, theoretically, on a multi-year excursion to Mars.

But what's interesting, and concerning, is that even with those protections we do see signs of radiation damage to astronauts, Cucinotta told me.

The big thing is cataracts — changes in the lens of the eye that make it more opaque. With less light able to get into their eyes, people with cataracts lose some of their ability to see. In 2001, Cucinotta and his colleagues looked at data from the ongoing Longitudinal Study of Astronaut Health, and found that astronauts who had been exposed to higher doses of radiation (because they'd flown more missions in space, or because of the specifics of the missions they'd been on*) were more likely to develop cataracts than those who had been exposed to lower doses.

There's also probably an increased risk of cancer, though it's difficult to estimate how much, exactly. That's because we don't have human epidemiological data about the kind of radiation astronauts are exposed to. We know the rates of cancer for survivors of the nuclear bombs dropped on Hiroshima and Nagasaki, but that radiation isn't really comparable to the stuff in Galactic Cosmic Radiation. In particular, Cucinotta is concerned about particles known as HZE ions.

These particles are very heavy and very fast and we don't experience them here on the ground. They're the kind of things that get filtered out and broken down by Earth's defense systems. But HZE ions can cause more damage, and different kinds of damage, than the radiation scientists are really familiar with. We know this because scientists actually compare samples of astronauts' blood before and after a spaceflight.

Cucinotta calls this pre-flight calibration. Scientists take a blood sample from an astronaut before the launch. While the astronaut is in space, the scientists divide that blood sample up and expose it to various levels of gamma rays — the kind of damaging radiation we're used to dealing with on Earth. Then, when the astronaut comes back, they compare those gamma ray-affected samples to what has actually happened to the astronaut while in space. "You see about a two-to-three fold difference across the population of astronauts," Cucinotta told me.

One example of how HZE ions are different: They seem to be able to affect cells they don't even touch. In non-human trials, these non-targeted effects can happen in cells up to a millimeter away from the cells that have actually been irradiated and we don't really know what that means yet. But it definitely changes the way we think about radiation risks, which is a model based on the assumption of a direct, linear connection between dose and risk. With HZE ions, that might not be true.

All of this explains why studies like the one published last week are going on. It's not that we're seeing horrible effects in astronauts who've been to space in the last half-century. Instead, there are two things those astronauts have shown us. First, there are genetic changes and damage happening even within the relatively safe confines we've traveled thus far. Second, there is a hell of a lot we don't know about how radiation exposure and risk works in outer space. It's almost like we can smell gas in our house, but we don't yet know whether there's a serious leak, or we just left a stove burner on for a couple minutes.

If our future really does lie in the stars, then this is a mystery we're going to have to figure out.

FURTHER READING:
• The new paper on Galactic Cosmic Radiation and Alzheimer’s disease
• An introduction to the space radiation environment
• NASA primer on cosmic rays
• A 2006 essay in The Lancet, written by Francis Cucinotta, about cancer risk and Galactic Cosmic Rays
• Cucinotta's 2001 paper on cataracts in astronauts
• A 2004 NASA Science News piece that also explores cataracts in astronauts

X-Ray Specs — the cheap glasses that ostensibly allow you to see the bones in your own hand and/or ladies' undergarments — are instantly familiar to anybody who read comic books in the 20th century. Last week, The Onion AV Club shared a fascinating video showing that immature gags about x-ray vision began long before the Marvel Comics' advertising department was even a glimmer in somebody's eye.

"The X-Ray Fiend" was a short film produced in 1897 — just two years after William Rontgen gave x-rays their name. It's basically an X-Ray Specs gag writ large, with the aforementioned fiend checking out the insides of a necking couple. You can watch it at The Onion.

That video sent me toodling around through some of the fascinating history surrounding x-rays in pop culture. Rontgen wasn't the first to discovery x-rays, but he was the first person to really study them in depth and his x-ray photograph of his wife's hand kicked off a public sensation. To give you an idea of how into x-rays everybody was for a while, the AV Club story actually includes a link to a 19th century Scientific American how-to that promised to teach the reader to make their own x-ray machine at home. You know. For funsies.

It's kind of crazy how popular x-rays became, considering how dangerous they can be. The Scientific American piece, for instance, now comes with a 21st century disclaimer warning that "Many operators of the early x-ray systems experienced severe damage to hands over time, often necessitating amputations or other surgery." Which brings us to Clarence Dally ...

In 1895, Dally was working for Thomas Edison, one of the enthusiastic engineers clocking 90-hour work weeks in Edison's proto-Silicon Valley tech startup. He jumped into x-ray research, attempting to take the new discovery from parlor toy to medical tool. But, in the process, Dally managed to expose himself (repeatedly, and for hours at a time) to levels of radiation that were, by today's standards, incredibly high. Within five years, he had made himself very sick. Here's a Smithsonian story, describing what happened to Dally:

By 1900, he began to show lesions and degenerative skin conditions on his hands and face. His hair began to fall out, then his eyebrows and eyelashes, too. Soon his face was heavily wrinkled, and his left hand was especially swollen and painful. Like a faithful mucker committed to science, Dally found what he thought was the solution to prevent further damage to his left hand: He began using his right hand instead. The result might have been predictable. At night, he slept with both hands in water to alleviate the burning. Like many researchers at the time, Dally assumed he’d heal with rest and time away from the tubes.

By the following year, the pain in Dally’s hands was becoming intolerable, and they looked, some people said, as if they’d been scalded. Dally had skin grafted from his leg to his left hand several times, but the lesions remained. When evidence of carcinoma appeared on his left arm, Dally agreed to have it amputated just below his shoulder.

It took stories like this to turn average people off from being home x-ray fiends.

• Read the story of Clarence Dally at Smithsonian
• The Onion AV Club, Best Films of the 1890s
• Scientific American shows you how to build an x-ray machine, which you really should not do

At Grist, Jess Zimmerman has an interesting piece about a lake near a notoriously leaky former Soviet nuclear research site, where the radiation level is so high that an hour on the beach can be enough to kill you.

You can’t really blame Lake Karachay for acting up — it comes from a really rough area. The lake is located within the Mayak Production Association, one of the largest — and leakiest — nuclear facilities in Russia. The Russian government kept Mayak entirely secret until 1990, and it spent that period of invisibility mainly having nuclear meltdowns and dumping waste into the river. By the time Mayak’s existence was officially acknowledged, there had been a 21 percent increase in cancer incidence, a 25 percent increase in birth defects, and a 41 percent increase in leukemia in the surrounding region of Chelyabinsk. The Techa river, which provided water to nearby villages, was so contaminated that up to 65 percent of locals fell ill with radiation sickness — which the doctors termed “special disease,” because as long as the facility was secret, they weren’t allowed to mention radiation in their diagnoses.

Read the rest at Grist

Science blogger Ed Yong whipped up this awesome graphic and made me a one-off tshirt to wear to radiation treatment for breast cancer.

Cancer patients, radiation oncologists, radiation therapists, and the people who love them all can make their own t-shirts and stickers with the JPEG if you are so inclined!

Thanks, Ed!

]]> http://boingboing.net/2012/09/10/for-those-with-cancer-make-yo.html/feed 7 http://boingboing.net/2012/06/05/radiation-is-like-an-angry-wif.html http://boingboing.net/2012/06/05/radiation-is-like-an-angry-wif.html#comments Tue, 05 Jun 2012 15:19:11 +0000 Rob Beschizza http://boingboing.net/?p=164766 compared radiation to a nagging wife. Apologies have been made. Reuters' Miki Kayaoka:

The Japanese Atomic Energy Agency devoted a page on its website to an effort to "make the hard words used in the nuclear power industry" more easy to understand, particularly for women.

A public info campaign in Japan compared radiation to a nagging wife. Apologies have been made. Reuters' Miki Kayaoka:

The Japanese Atomic Energy Agency devoted a page on its website to an effort to "make the hard words used in the nuclear power industry" more easy to understand, particularly for women. The page, which included a cartoon of an angry, fist-waving wife and her cowering husband, compared the wife's yell to radiation. It continued the metaphor by saying that the women's increasing agitation could be compared to "radioactivity", while claiming the wife herself was comparable to "radioactive material".

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Science blogger Lee Falin has a potentially useful analogy for putting radiation dose and risk into perspective—treat it like currency. Part of the problem with explaining radiation is that there are multiple units of measurement in play and they're all unfamiliar to the average Joe and Jane. The numbers get confusing quickly and when numbers get confusing, most people just tune them out. "Blah blah blah blah radiation blah blah" is both an unhelpful message, and an often terrifying one.

Falin tries to get around that problem by putting radiation doses into a number system that everybody knows and uses every day—money. He starts by deciding arbitrarily that 1 sievert of exposure is worth $1000. Once you've got that established, it's easier to understand relative doses. In this system, getting $4000 all at once is a deadly dose. Most of us get $2.00-$3.00 a year in background radiation exposure. A mammogram is worth .40.

This is not a perfect method. In particular, it seems to work best for acute exposure. Falin still hasn't totally solved the problem of explaining the accumulation of radiation over time. But I think that this idea—thinking of radiation doses in terms of money—could go a long way to helping some people understand this stuff a little better. I really liked how he explained cancer risks, for instance:

What about the long term risk of cancer caused by radiation exposure? According to the EPA, an average of 2,000 out of every 10,000 adults will die from some form of cancer. If you expose everyone in that group to an extra $10.00 of radiation in one year, the number will jump to about 2,005 people.

Read the rest at Everyday Einstein

After much discussion and review with the Safecast team, we decided that a key component of the user experience should be a graphic display, instead of a 7-segment LED readout. Therefore, a 128×128 pixel OLED panel was incorporated into the design. The OLED panel would be mounted behind a continuous outer shell, so there would be no seams or outward design features resulting from the introduction of the OLED. However, as the OLED is not bright enough to shine through an opaque white plastic exterior shell, a clear window had to be provided for the OLED. As a result, the naturally black color of the OLED caused the preferred color scheme of the exterior case to go from light colors to dark colors. User interaction would occur through a captouch button array hidden behind the same shell, with perhaps silkscreen outlines to provide hints as to where the buttons were underneath the shell. I had originally resisted the idea of using the OLED because it’s very expensive, but once I saw how much an LND7317 tube would cost in volume, I realized that it would be silly to not add a premium feature like an OLED. Due to the sensor alone, the retail price of the device would be in the hundreds of dollars; so adding an OLED display would help make the device “feel” a lot more valuable than a 7-segment LED display, even though the OLED’s presence is largely irrelevant to the core function of the apparatus.

Safecast Geiger Counter Reference Design ]]> http://boingboing.net/2012/03/15/bunnie-huangs-open-geiger-co.html/feed 12 http://boingboing.net/2011/11/10/hacking-geigers-safecast-crow.html http://boingboing.net/2011/11/10/hacking-geigers-safecast-crow.html#comments Fri, 11 Nov 2011 02:21:27 +0000 Xeni Jardin http://boingboing.net/?p=128642 Online "Hacker" Group Crowdsources Radiation Data for Japanese Public on PBS. See more from PBS NEWSHOUR.On PBS NewsHour tonight, a report I helped the program's science correspondent Miles O'Brien produce about the challenge people in Japan face of finding and sharing reliable data about radiation contamination, after the disaster at the Fukushima Daiichi nuclear plant.]]>

Watch Online "Hacker" Group Crowdsources Radiation Data for Japanese Public on PBS. See more from PBS NEWSHOUR.

On PBS NewsHour tonight, a report I helped the program's science correspondent Miles O'Brien produce about the challenge people in Japan face of finding and sharing reliable data about radiation contamination, after the disaster at the Fukushima Daiichi nuclear plant.

Embedded above, a conversation between Miles and NewsHour host Hari Sreenivasan about our report, which focuses on a grassroots group called Safecast that measures, maps, and publishes data on radiation contamination levels throughout the country.

While in Tokyo, Miles spoke to Hari Sreenivasan about his trip with Safecast workers into the voluntary exclusion zone around the Fukushima Daiichi nuclear plant, where they detected levels reaching the equivalent of six X-rays per day.

He also filled us in on his conversations with Japanese officials working in evacuated areas and Japanese residents eager for more information about the consequences of the nuclear accident.

I'll post the video for the full feature when it's available online.

That last source of exposure works because the higher you get, the less you can rely upon Earth's atmosphere to shield you from radiation in space. It's the same reason why there's an increase in radiation exposure associated with climbing a mountain. All of these exposures are small. Small enough that most people don't need to worry about them. (For instance, a pregnant woman can safely take an airplane trip. You'd have to be a pregnant flight attendant, regularly working long-haul flights, before the exposures would start adding up to a quantifiable risk.)

But because we use these small-dose numbers to talk about relative risk and when radiation should and shouldn't scare us, it's interesting to know where they're coming from ... and how accurate they are. That's why I was interested in something weird noticed by Ellen McManis. She operates a research nuclear reactor at Reed College in Portland, Oregon, and like many of us, she's curious about how much radiation people are actually being exposed to as a part of everyday life. Unlike us, however, McManis actually has access to things like dosimeters. With the help of her colleague, Reuven Lazarus, she recently took one on a cross-country plane flight—from Portland to DC, with a layover in Chicago. To her surprise, she found that the dose her dosimeter registered was actually a lot lower than the dose she'd been expecting.

I was using a RADOS RAD-60 dosimeter, which gives you an instant reading of how much radiation you've been exposed to while the dosimeter is on. We use them for visitors and people who don't have their own permanent dosimetry yet. Over the course of ~5 hours on the plane, I got a total of 0.3 millirem (or 3 microsieverts). I usually see a number quoted of 1 millirem per hour [for airplane exposure], or 3-to-5 millirem per cross-country flight, so that's an order of magnitude lower than expected.

Now that is interesting. If you look at Randall Munroe's Radiation Dose Chart (my favorite source for putting these small doses into context), you'll see that his well-researched numbers estimate an exposure of 40 microsieverts (the same thing as 4 millirem) for one cross-country plane flight. McManis' real-life reading was definitely a lot lower than the go-to estimate.

But why?

The truth is that McManis didn't really know. Her dosimeter was recently calibrated. She also checked it against a known source of radiation in the lab, and had turned up a result that was completely normal, so it seemed like this wasn't an issue of a wonky dosimeter.

Luckily, off-duty nuclear scientists aren't the only people taking measurements of in-flight radiation exposures. The official estimates, the ones used by people like Randall Munroe, come from an organization called the French Institute for Radiological Protection and Nuclear Safety.

Back in 1996, the European Union started counting radiation exposure on board airplanes as an occupational safety hazard. Remember, travelers generally don't have anything to worry about. But, for people who work on airplanes, the risk is large enough to be worth paying attention to, especially on certain routes. EU-based air crews are limited to 100 millisieverts of exposure every 5 years, and 50 millisieverts in any given year*.

How do they track that? You could, theoretically, give a personal dosimeter to every person working onboard an airplane. But that gets expensive, for reasons we'll talk about later. Instead, the EU has chosen to manage this with a system based on computer models—models that have been verified against more than 10,000 hours worth of real-world dosimeter readings.

It's called the Sievert System, and it works because the sources of radiation at 30,000 feet are fairly constant. Subatomic particles come from the Sun and from deep space to bombard our atmosphere. Reactions between those particles and our atmosphere produce secondary particles. Those secondary particles penetrate airplanes, and our skin, where they can damage our DNA.

There are factors that can alter the dose. Solar activity, for instance, means an increase in subatomic particles striking the atmosphere. Altitude matters, because the higher you are, the less atmosphere there is to protect you. Finally, latitude is also important. The particles penetrate our atmosphere more easily at the poles, says Jean-François Bottollier-Depois, head of the External Dosimetry Department at the French Institute for Radiological Protection and Nuclear Safety. By the time you get to 60 degrees latitude, he says, you will be experiencing a dose 2x as high as that at the equator. (Again, remembering that we're talking about very small doses.)

But these are all issues that can be factored into a computer model. All you need to know is the routes a pilot or crew member will fly in a given month, and the level of solar activity. The Sievert System uses that information to calculate monthly exposures for individuals.

Bottollier-Depois says the System also checks its work. Back in the early 90s, his team tracked the doses received by cosmonauts aboard Mir, so they know what the dose is in space. Earthside, they sent dosimeters on numerous flights, choosing a variety of routes, and taking measurements in different locations on the planes. They also used multiple dosimeters on each flight, so they could be sure that the dose recorded was accurate. And they still do these practical tests today, updating the Sievert System database to account for long-term changes in solar activity.

With all that experience under his belt, Bottollier-Depois had a pretty good idea of why Ellen McManis' measurements came out so wrong. In fact, it has to do with why the EU chose a model-based system, rather than real-time, individual dosimetry. All dosimeters are not created equal.

"If you use a classical dosimeter, it is measuring photons and electrons, but those account for less than 40% of the total dose aboard aircraft," he says. "The difference comes from the fact that you have other particles like neutrons, and those represent most of what you receive in a dose aboard an airplane. They can't be detected with classical dosimeter. You need very specific technology for that."

Expensive, specialized dosimeters pick up the particles that are most common at flight altitudes. Normal, old dosimeters don't. To McManis, that difference makes a lot of sense.

"I was using a personal alarm dosimeter that relies on ionizations to work, and neutrons don't ionize things," she says.

For more information, check out these links:

French Institute for Radiological Protection and Nuclear Safety — How far advanced is research on the health effects of low doses?

Sievert System page — You can calculate your own flight exposures here, and learn more about how the system works. (Heads up: In my experience, the site is often not working. If it won't load, check back in a couple days.)

The good news: This has nothing to do with Fukushima. It turned out to be an extremely localized hotspot, and officials found the real source nearby.

The bad news: The real source turned out to be something the AP is describing as "mystery bottles" stored under someone's house. No. Really.

So, I guess the takeaway to this story should be something like: Japanese officials find source of radiation hotspot, and are no longer worried that it's being caused by Fukushima. Instead, they are now worried about why somebody in Tokyo is storing bottles of a radioactive substance under a house.

My old employers, mental_floss magazine, have a new editor and some cool new stories out in their September/October issue. One is about a kid who built a nuclear reactor at age 14. No, not that kid. Meet Taylor Wilson, a kid who shares some hobbies with the more-famous "Radioactive Boy Scout" David Hahn, but with, apparently so far, less tragic results. (It helps that Wilson, unlike Hahn, discussed his plans with adults who helped set him up with the right safety environment to build his reactor in.) Another difference: Wilson's interests lie with fusion, not fission.

By the time Wilson stumbled across Fusor.net, 30 hobbyists worldwide had managed to produce the reaction; Wilson was determined to become the thirty-first. He started amassing the necessary components, such as a high-voltage power supply (used to run neon signs), a reaction chamber where fusion takes place (typically a hollow stainless steel sphere, like a flagpole ornament), and a vacuum pump to remove air particles from the chamber (often necessary for testing space equipment).

Wilson also funneled money collected from Christmases and birthdays toward buying radioactive items, many of which, to his surprise, were available around town. Smoke detectors, he learned, contain small amounts of a radio-active element called americium, while camping lanterns contain thorium. In antique stores, he found pottery called Fiestaware that was painted with an orange uranium glaze. Wilson trolled websites such as eBay for an array of nuclear paraphernalia, from radon sniffers to nuclear fuel pellets, and came to own more than 30 Geiger counters of varying strengths and abilities. Most of Wilson’s radioactive acquisitions weren’t dangerous, given their small quantities. But a few—vials of powdered radium, for example—could be fatal if mishandled, which is why he’s never opened them. (Although he’s been tempted.)

There's a longer preview of the story online. The rest is in the new print issue.

During the early weeks of the Japan 3/11 crisis, after a tsunami critically damaged the Fukushima Daiichi nuclear power plant, we talked on Boing Boing about why Americans on the West Coast didn't need to worry about exposure to radioactive fallout. Shorter version: The levels of radiation that made it across the Pacific were far too low to cause a serious health concern.

Now here's something really interesting: The levels of fallout that made it across, while too low to pose a risk to humans, were detectable by extremely sensitive scientific equipment. And those measurements are now being used to document what happened at the site of the disaster.

In the process of trying to cool down the overheating reactors, officials in Japan dumped sea water and reaction-slowing boric acid into the reactor cores. The resulting chemical reaction—chloride ions in salt water combining with fast-moving neutrons from the reactor—produced a form of radioactive sulfur. Meanwhile, scientists at the University of California, San Diego, were already measuring sulfur particles in the air as part of climate research. Days after the crisis began, their instruments picked up the radioactive sulfur that had crossed the ocean.

Now, using modeling and some basic knowledge about how particles behave, they've been able to use the information they gathered in California to estimate how high radiation levels were in Fukushima in the early days of the crisis. A couple of things they've found: Further evidence that at least one of the reactor cores suffered a meltdown, and evidence suggesting that the damaged reactors didn't re-start after the emergency began—a possibility that has been pointed out by other scientists. I'll have a more in-depth look at this study later this week. For now, check out the write ups at Nature News and USA Today.

The full research paper is at The Proceedings of the National Academy of Sciences.

(Thanks, Miles O'Brien + Jenny Marder of PBS NewsHour)

This image shows two spots at the Fukushima nuclear power plant in Japan, at the bottom of a ventilation stack between the No.1 and No.2 reactors, where radiation levels are still high enough to kill a human being. I'm talking about the quick-death-by-radiation-poisoning sort of "kill," not the possible-death-by-cancer-at-some-point-in-the-future sort. At the colored spots, radiation levels were measured at 10 sieverts (10,000 millisieverts) per hour.

The image was captured using a gamma ray camera, the same sort of equipment that researchers use to track radioactive isotopes in the human body as part of medical treatments.

Via David Biello and the Atlantic Wire

Irradiating food doesn't make it radioactive, and it does kill dangerous bacteria, like the E.coli that killed many Europeans this summer. But it's also not a panacea against food poisoning and it's definitely not the most popular idea ever thought up. In a column in the New York Times, Mark Bittman examines the evidence behind irradiation, and how that evidence does and doesn't get considered in the choices we make about food.

When it comes to irradiation, you might need a primer. (I did.) Simply put, irradiation — first approved by the FDA in 1963 to control insects in wheat and flour — kills pathogens in food by passing radiation through it. It doesn’t make the food radioactive any more than passing X-rays through your body makes you radioactive; it just causes changes in the food. Proponents say those changes are beneficial: like killing E. coli or salmonella bacteria. Opponents say they’re harmful: like destroying nutrients or creating damaging free radicals.

Many people are virulently for or against. Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, says that irradiation “could do for food what pasteurization has done for milk.” (The main difference between irradiation and pasteurization is the source of the energy used to kill microbes.) Wenonah Hauter, the executive director of Food & Water Watch — which calls irradiation “a gross failure” — told me it was “expensive and impractical, a band-aid on the real problems with our food system.”

There are a few people in the middle. Former assistant secretary of the Department of Agriculture (USDA) Carol Tucker-Foreman is mostly anti-, but said that if she ran a nursing home or a children’s hospital — a place where people with weaker-than-average immune systems were cared for — it “might be something I wanted to do.” Marion Nestle, a New York University nutrition professor and the author of “Safe Food: The Politics of Food Safety” (and a food-movement icon), allows that “the bottom line is that it works pretty well if done right, and I’m not aware of any credible evidence that it does any worse harm to foods than cooking. But it isn’t always done right, and foods can become re-contaminated after irradiation.”

The current evacuation zone in Fukushima is only 20-30 kilometers. The Japanese government has compensated the evacuees from inside that zone and has financially supported them in moving out of it. However, as more and more high levels of radiation are being discovered outside of the evacuation zone, many more Fukushima residents (and many others located nearby Fukushima) want the government to also help them logistically and financially so that they can move out further away from the nuclear plants. Especially since many children are now being exposed. But the government does not want to do this at all and many people are getting very upset. This video was filmed in Fukushima at the Corasse Fukushima Building on July 19, 2011. The meeting was entitled "Japanese Government Discussion - Demands for Evacuation Authority". This meeting was attended by residents of Fukushima and some Representatives for the Nuclear Safety Commission Of Japan. It was filmed by some anonymous members of the "Save Child" website. This site includes Japanese news about the Fukushima Nuclear disaster, advice on how to avoid contamination, and many, many related videos. This site is much like enenews.com on steroids! I checked domaintools.com and the name of the registration is private. You can see the original Japanese videos of this meeting on the Save Child website here (English), and on Youtube here. This video was translated by pejorativeglut. And, for sure, the English subtitles are correct. I was not involved in the production of this video.