Wednesday, February 22, 2017

Some Numbers on the European Radioactive Iodine Story

An interesting little story popped up this week about radiation being detected across Europe, spreading from Norway to Spain.  In a way, it's as strong a click bait headline as anything they could put up, but there are some interesting details about this.  The US dispatched a specially modified aircraft, called a WC-135 to the area.  Think of it as a KC-135 (Boeing 707) modified to sample and monitor for radiation.
An interesting part of this story is that the isotope being reported is Iodine 131 which has the rather short half-life of  8.04 days (.04 days is just under 1 hour).  That means the release of this material has to have been rather recent.  It was reported by the French nuclear agency (ISRN) on February 13th that it was first detected six weeks prior to that.
Iodine-131 (131I), a radionuclide of anthropogenic origin, has recently been detected in tiny amounts in the ground-level atmosphere in Europe. The preliminary report states it was first found during week 2 of January 2017 in northern Norway. Iodine-131 was also detected in Finland, Poland, Czech Republic, Germany, France and Spain, until the end of January.
Anthropogenic, of course, means that it's typically only created by human efforts.  Certainly, it could have come from a fission bomb, but there are global networks to detect nuclear tests and they don't report anything suspicious.  Where else does it come from?  It turns out that this isotope is routinely produced for medical testing.  Could it be a lab accident?  

Let's ignore that for a moment and talk numbers.  The ISRN report says
In France, particulate 131I reached 0.31 µBq/m3 and thus the total (gaseous + particulate fractions) can be estimated at about 1.5 µBq/m3. These levels raise no health concerns.
What's a µBq/m3?  It gets a bit dense with details for a bit here, so I'm going to lift most of this explanation  from PJ Media's Charlie Martin.  That abbreviation represents a rate, and means 1 micro (millionth of) 1 Bequerel per cubic meter.  A Bequerel is a measure of how much radioactive material there is. 1 Bq means that one atom is decaying every second.  Saying 1.5 micro Bequerel implies one millionth of one atom is decaying but that just can't happen; atomic decay only applies to whole atoms.  To turn that into a whole number, you have to multiply the whole thing by 2 million, which says 3 atoms are decaying in 2 million cubic meters per second.

Two million cubic meters is a big volume, but does it help you visualize it better if I say 3 atoms are decaying in 70.63 million cubic feet?  Does it help if I convert that to 528 million gallons?  Neither of those help me visualize this large number, but Charlie Martin used an interesting example.  Remember seeing the picture of a German airship called the Hindenberg?  It had a volume of 200,000 cubic meters.   That's convenient because it means 10 of these Zeppelins would have 3 atoms of Iodine 131 decaying. 
Perhaps that's not a convenient visualization.  I find a lot of people have heard of the Banana Equivalent Dose (BED), an indication of the amount of radioactivity contained in a typical banana.  There's a little unit shuffling here (we're not talking cubic meters, after all), but it turns out that a BED is 15 Bequerels, or five times as much radioactive decay as in 10 Hindenbergs. 

The French ISRN stated almost immediately the levels were so low that this 131I is not a risk to health, and we see it's about equal to eating 1/5 of a banana.  Those agree since we know bananas aren't dangerous, except possibly calorically, if you have 27 bananas in one pie all in one sitting. 

The question, then, is still "where did it come from?"  131I is actually an important medical isotope, used for treatment mainly of thyroid disease -- thyroid cancer or Grave's disease. When it's used, the patient basically eliminates it through urine, and yes, the urine has to be treated as low-level radioactive waste, but inevitably a little bit escapes, especially places where maybe they aren't quite as careful as in the United States. Then it gets into the atmosphere, possibly from spray treatments of sewage, or something that creates an aerosol. 

It almost certainly wasn't from a nuclear weapons test, and there's a good discussion of why here.  In short form, other signs would have been detected. 

The most likely scenario, then, is  that some patients were given 131I for a thyroid disease, and went home.  Within a few hours, they urinated most of it into the sewer system, where some of it seems to have been discharged into the environment.  Maybe something malfunctioned at the sewage facility.  The radioactive decay will be gone within a couple of months (8 half lives would be 64 days) but was never a health hazard.  The only reason we know about it is that we can detect radiation at such absurdly low levels.


13 comments:

  1. Not related to the radiation did you know that the Boeing 707 can flip over and power dive breaking the sound barrier and pull out of the dive near sea level? Neither did I. Many years ago a friend in the AF was a Russian interpreter flying in a military 707 somewhere off the coast of Kamchatka. They were listening in to Russian transmissions and monitoring Russian aircraft. As often happened Russia scrambled a MIG and it was tracking them. My friend said it wasn't unusual and no one was worried because the Russian pilots weren't even allowed to sneeze without getting explicit permission from their control so nothing was going to happen except maybe a flyby. As the MIG came closer he locked his firing system on the 707. Again more or less standard practice in this situation to intimidate. But this time it was different. This time the MIG pilot repeated to his controller something along the lines of target locked on, missile armed... 'fire'! My friend looked at the man who was monitoring the radar for confirmation and got it and he flipped the switch to connect to the pilot and used a code phrase to let the pilot know what just happened. The next second the 707 flipped upside down, nosed down and headed for the ocean some 6 miles below them. My friend was wearing his seat belt and received minor injuries from manuals and other items flying around inside the cabin. About five guys were not belted in and hit the ceiling, then various consoles and finally came to rest under something when the plane leveled out just above the ocean. The was, as everyone discovered, the evasive maneuver for the 707 if a missile was fired at it. My friend said that he remained on the radio listening to the Russian pilot who had never actually physically seen the 707. The Russian was astonished to find that the 707 disappeared from his radar and began to wonder if there was really a target out there. His controller expressed some anger over the missile firing then disbelief that a plane could just disappear and finally skepticism about what the pilot and the ground radar had shown. The 707 just disappeared. It leveled off a few hundred feet above sea level and headed back to Anchorage to get the injured taken care of. This is quite a serious maneuver for a 'airliner'.

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  2. The 707 is/was one rugged airplane!

    As far as the radiation was concerned, yep, we can detect it at levels far below what it takes to cause any harm.

    But the press hears "Radiation", and instantly goes "ZOMG!!!! GODZILLAZ!!!".

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  3. There is also the possibility that the radiation levels are higher at the source. If iodine-131 is the only isotope, a medical release is possible. If it turns out that cesium-137, then there is another reason entirely.

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  4. Had a radioactive stress test some years ago. Interesting on several levels.
    The radioactive tracer is only good for a day, because of halflife.
    The nurse had a film badge on her finger, as well as one on her scrubs.
    I had planned on going straight to work after the test, and I left my uniform, kevlar, gun, and gunbelt in the car. On a whim I turned on the radiation pager and found it would alarm from 5 or 10 feet away. I called work and had a day off.
    When I went back to work more than 24 hours later, I still could not turn on my radiation pager, and when I walked close to my coworkers they would look at their gunbelts and get that particularly concerned look. (we kept the pagers on vibrate)

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  6. I saw a video, most likely on YouTube, of a 707 doing a barrel roll, and it's pretty darned impressive. I've read that Boeing's design philosophy has always been the pilot in command is in command, and he should be able to put that plane into any position he needs to.

    It's also kind of cool that the basic 707 airframe has been flying since the mid '50s.

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  7. That was Tex Johnston, Boeing's Chief Test Pilot, and he was flying the "Dash 80", the prototype for the 707. That airplane is now at the Smithsonian after Boeing refurbished it.

    The Dash 80, which Boeing had hoped to sell to both the USAF as the KC-=135, and the airlines, but the airlines wanted a wider cabin, requiring the whole airplane to be slightly redesigned.

    https://en.wikipedia.org/wiki/Boeing_367-80

    Tex's barrel roll can be seen here:

    https://www.youtube.com/watch?v=AaA7kPfC5Hk

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  8. Hello, new here. If the radiation can be traced in such small amounts. Is Fukishima being ignored?

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    1. I grew up in a house with a granite stone foundation. Granite is radioactive. In fact anywhere the scaremongers want to direct you to in the U.S. and feed your fear about radioactivity supposedly from Fukishima that scary radioactivity they are talking about is less than the granite was emitting every second of every day I lived there. Your clay flower pot also emits radioactivity. Depending on where you live the ground emits radioactivity. The good news is we can measure the smallest amount of radioactivity. The bad news is because we can measure it and categorize it and label it the fear mongers will try to scare you with it.

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    2. Far from ignored, I don't think you'd hear a word about Fukushima if not for the ability to detect radiation in very low doses.

      The other day, I saw a map that was supposed to be depicting the radiation detected from Fukushima, and it was a map of the expected tsunami heights from the event that started it all.

      To emphasize a little bit of Anon 10:32's point, if you go to Grand Central Station in New York City as thousands of people do every day, you walk into a place built of granite. If Grand Central Station were a nuclear power plant, it would be shut down for exceeding the maximum allowable annual dose of radiation for employees. That being said, it's not actually a dangerous place. That's how strict the rules are and how sensitive the detectors are.

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  9. Do ya think? enenews.com

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  10. Since I got cancer I have had about 25 CT scans and numerous xrays. Two of those CT scans were in conjunction with biopsies of the lung which are actually multiple CT scans as they try to stick the needle into the right spot. One CT scan is 70,000 banana equivalent doses. I now set off the scanners at Walmart when I exit the store LOL.

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    1. LOL. Do you have an expectation of how long that will last? Has it caused issues with air travel?

      On one business trip returning from Canada, I was standing in line for security and suddenly a guy showed up beside me with a little box in his hand. I didn't get a good look at it, but it was the size of a modern handheld radio (say 2 x 4 x 1" thick) only it wasn't a radio. I saw a couple of lights. He calls out "over here", another few guys join him, and they close in on a woman in the next waiting line over. She explains she had radiation treatment of some sort, showed them a letter, and after a few minutes of talk, everything concludes with a cheerful, "have a nice day" all around. I was impressed that they picked out this one woman in one of several lines of people from across the room. Those are some good sensors.

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