Friday, April 22, 2011

Fukushima Nuclear Power Risks and a Real World Example

Everyday, at the very top of this blog, you can see a link to what the daily radiation rates are in Tokyo and Tsukuba (75 miles north of Tokyo, towards Fukushima). The rates have fallen well within safe limits (actually hundreds of times within safe limits since the earthquake on March 11, 2011). 
Beach Boys - Don't Worry Baby
Nevertheless, I still get comments from people who mention nonsense along the lines of "background radiation levels are not the same as ingested radiation levels." Oh really? Thanks for all the Little Einstein's who have popped up recently and have become experts at radiation. No, ingested levels of radiation are not the same as background radiation levels. Absolutely correct.

That's why I do not show levels of radioactivity at the Fukushima power plant. I only show the levels in Tokyo and surrounding areas. I'm sure that if you are one of the few hundred people working at or in the plant for clean up then there is a danger. But I am not talking about the levels at Fukushima. I am talking about the levels in Tokyo. 

Tokyo is 230 kilometers away from Fukushima. No one in Tokyo is inhaling Plutonium... I'm sure there's lots of things people in Tokyo are inhaling, but Plutonium or other dangerous airborne radioactive particles are not some of them.



Once again, as I have written before, the issue comes down to facts and technology. Tabloid sensationalism that the mass media is giving the public is pure and simple nonsense.   

Why do people have such short memories? Don't people remember how the mass media said that Swine Flu was going to kill over 50 million people? As I wrote just 5 days into the nuclear accident in: Japan Nuclear Disaster Update & Strong Criticism of Western Media Sensationalism:

Actually, it astounds me that people do accept what what the media says as gospel truth. Don't forget that this is the very same media that told us 3 years ago that Swine Flu was going to kill more than 50 million people worldwide. This was the same media that told us that the USA had to invade Iraq because of Saddam's nooklar weapons. This was the same media that told us that SARS also was a killer virus that was going to wipe out entire populations. This was the same media that told us that Bird Flu was going to do the same.

As of today, worldwide 
deaths from Swine Flu: 82. No nuclear weapons for Saddam (if he had any, do you really think we would have invaded Iraq?). Worldwide deaths from SARS: 100. Worldwidedeaths from Bird Flu: 80. Don't even get me started on Man Made Global Warming!

Fact of the matter is that this is the same media who constantly exaggerates stories in order to sell advertising space to an extremely gullible public. When will people ever learn? If history is any example then the answer is: Never. They'll never learn.

Just wait a year or three for the next killer disease and we can start all over again. 

I've stated it over and over; we live in a world of hype versus reality. You can choose which to believe. It seems that far too many wish to believe tabloid hype. 

Well, now, once again, a technlogy publication has come out with the facts to try to battle it out with those who are spouting off nonsense.

Today's recommended article comes from Boing Boing, one of the premiere technology publications in the world today. In this article, they break down the facts very simply. I'd like to quote it in full:


chartthing.jpg
Last night, Xeni posted a link to this chart, showing radiation readings taken in all of Japan's different prefectures, except for Fukushima. I thought it might be useful to put this chart in context with what I've learned about radiation dosages and health from speaking with several health physicists over the last couple of days.
First off, a little bit of background. These measurements are coming from the Japanese government, and they're only showing what's going on at one place in each prefecture. It's entirely possible that other people, taking measurements at other locations, would get different numbers. Also, as you can see in the image above, this is showing change in radiation levels over the course of this Wednesday, Thursday, and Friday—March 16 through March 18. The measurements might have been higher or lower in the days preceding this sample, or in the days to come.
Disclaimers thus made, let's talk about what these charts show ...



The Basics

• Thanks to the magic of Google Translate, we can see that the measurements are taken in micrograys per hour. There are a lot of different units of measurement for radiation levels. I've been working mostly in either millisieverts or rems. So I'm going to convert this: 1 microgray = .001 millisievert
• So, now let's look at the prefecture with the highest spike in radiation levels. That would be Ibaraki Prefecture. If I'm understanding the chart correctly, the name in parenthesis tells you where, in general, the measurement was taken within the prefecture. So, in this case, the measurement comes from Mito, a city about 2.5 hours North and East of Tokyo.


On Wednesday, radiation levels at this one location in Mito spiked at .001 millisievert per hour (1 microgray), but didn't stay there for very long. Before Thursday, levels had fallen back to 0.00025 millisievert per hour, and they've mostly stayed about that level ever since—though it looks like the levels might be falling further today.



What The Doses Mean

• Let's look back at the dose and risk table put together for BoingBoing by the Mayo Clinic health physicist Kelly Classic. There's no entry for .001 millisievert on that table. The lowest it goes is .04 millisievert—the equivalent of a flight from New York to LA. It's a dose so small that it isn't associated with any increase in the lifetime risk of cancer.
• But time matters too, not just dose. This isn't just .001 millisievert, but .001 millisievertper hour. If you were exposed to that steadily, for 12.5 days, you'd end up with an actual dose of .3 millisievert—the equivalent of 30 days of natural background radiation, according to Kelly Classic's dose table. That's well above normal levels, but, again, even .3 millisieverts is still a dose that's so low, scientists can't find any evidence that it raises the lifetime risk of cancer.
More importantly, the radiation readings in Mito were only picking up .001 millisievert per hour for a short period of time. So, while that spike was big, it's unlikely to represent an equally significant increase in health risk.
• There's one final thing that matters here, though. Radiation levels in Mito started out at .00025 millisieverts an hour on Wednesday morning. That's where they fell back to after the spike. And they've been roughly around that same level ever since.
.00025 millisieverts an hour isn't normal. And that can start to add up.
There's 72 hours in three days. At .00025 millisieverts an hour, that gets you to a true dose of .018 millisieverts. Assume the spike lasted 3 hours, and that means the people of Mito have probably gotten close to .021 millisieverts over the last few days—about half the radiation exposure of a flight from New York to LA. The good news is that their overall risk is still low. To reach the point where your lifetime risk of cancer increases by 1%, you'd have to be exposed to 100 millisieverts. That could happen, if radiation keeps leaking out of Fukushima long enough, or if levels go up. But, so far, even though the dose is far higher than normal, the risk is lower than you might think.



Putting It All Together

• I think this is a really useful example, because it does a particularly good job of showing you how radiation dosages can add up for people living in the direct path of radioactive fallout—there's a reason why we're worried right now about the people who live in places like Mito. But it also demonstrates how fear can be larger than risk. This far from the nuclear power plant—Mito is three hours south of Fukushima—it would take a much larger output of radioactive materials and/or a much longer crisis to really put people at any noticeable risk. (Tokyo is easily 4.5 hours by car - traveling at 80 km per hour - south of Fukushima).


Right now, according to these numbers, the only people in serious danger are still the ones working inside the damaged power plant, and the only people with measurable risks are the ones who live very close nearby.


Here is a chart showing the radiation levels in Tokyo as of right now:


The levels today are a about twice as high as they were on March 1, 2011. Which still makes Tokyo having a radiation level at about 1/4th that of the daily levels in Rome, Italy.

The facts speak for themselves. In spite of that, if you still want to panic, be my guest. It's doing nothing but ruining your mental health.

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