I have a DISCLAIMER, that among other things points out clearly that I am not an expert. Basically, I just google around and throw things together the best I can and add my opinion here and there. In short: think for yourself.
But please do comment if you spot an error.
(For the data that suggest that Fukushima = 3000+ times Hiroshima Cesium & 20,000+ times Nagasaki Strontium, see Conclusion & After-thoughts at the end of this blogpost.)
Well over a year ago, on May 25, 2012, I pointed out that “Fukushima’s Cs-137 is NOT “Four Chernobyls” ! (Russia Today spreading misinformation)“, and in that blog post I clarified how RT was confusing ‘raw data’ with “iodine equivalent” (a x 40 factor).
The data about the scope of the nuclear disaster already showed that Fukushima was on par with Chernobyl (something the industry had yet to publicly admit), but as far as Cesium-137 went, it was still believed to be significantly less severe.
Turns out that was based on extremely limited data. Revelations since June 2013 have changed the understanding of the magnitude of this ongoing disaster. It is now established fact, even for Cesium-137 and Strontium-90, that Fukushima is much worse than Chernobyl. The only good news is that most of this released radioactivity has not left the site of the Fukushima-Daiichi Nuclear Power Plants (yet…), but is being stored in (leaking) water tanks. This blogposts takes you on a walk through various data sources, many of which are not yet fully in agreement…
Sept 5, 2013 — An overview of fission material onsite, as well as estimated radioactive releases (stored or released into earth, water or air):
- First of all, even studies that have been published very recently, such as the “Cesium, iodine and tritium in NW Pacific waters – a comparison of the Fukushima impact with global fallout”, published on August 15, 2013, used long-obsolete data, such as those gathered on the JUNE 2011 Ka’imikai-o-Kanaloa (KOK) international expedition, on which they analyzed for Cs-134, Cs-137, I-129, and H3. Example:
Regarding these June 2011 sample data shown above, they noted: “The Cs, I and H levels in surface seawater offshore Fukushima varied between 0.002–3.5 Bq/L , 0.01–0.8 μBq/L, and 0.05–0.15 Bq/L, respectively. At the sampling site about 40km from the coast, where all three radionuclides were analyzed, the Fukushima impact on the levels of these three radionuclides represents an increase above the global fallout background by factors of about 1000, 50 and 3, respectively.” And then they go on modeling based on those findings, completely ignoring the since-widely-reported massive leaking of highly radioactive water into the Pacific. August 2013, that could perhaps come with a footnote pointing out that recent revelations have rendered those data unfit to be used for such modeling? Nope. Nothing. Odd, because:
- Already in Autumn 2012, the Woods Hole Oceanographic Institution (WHOI) had already made public that, based still-elevated concentrations of certain isotopes, they concluded that (Nov. 2012) “[…] there may be a continuing source of radionuclides into the ocean, either in the form of low-level leaks from the reactor site itself or contaminated sediment on the seafloor. […]” Graphic from the same website:
The above shows fish monitoring data available from the Japanese Ministry of Agriculture, Forestry and Fisheries (MAFF), showing the change (or lack thereof) in total cesium (137Cs + 134Cs in Bequerels per kilogram) in bottom-dwelling (demersal) fish from the five prefectures in East Japan closest to the Fukushima Dai-ichi nuclear power plant. For more from the WHOI, see also http://www.whoi.edu/main/topic/fukushima-radiation
It’s actually very easy to spend hours and hours searching for what should be a pretty simple question:
HOW MUCH (estimates in Bq) of the main radioactive isotopes (Cs-134, Cs-137, I-131, Sr-90, Sr-89,…) has been released (stored or escaped) from Fukushima, SO FAR?
You know, the reports vary widely.
For Cs-137, it appears the estimate has grown from TEPCO’s early estimate of 15 PBq to 100 Pbq, 160 Pbq, more than 212 Pbq in the water tanks + an unknown rest, to 276 Pbq and rising.
A sampling of such reporting:
- The World Nuclear Industry Status Report 2013, published in their July 2013 report the following:
- Cesium-137: 276 PBq (i.e. 40 percent of the reactor core inventory) […]
- […] about 2.5 to 3.3 times [Chernobyl], depending on the estimate, the total amount released into the environment from the Chernobyl accident.
- […] In June 2013, it was revealed that the groundwater sampled from a monitoring well adjacent to the Unit-2 turbine building is contaminated with strontium and tritium, so the highly radioactive water that filled the unit basement has already made its way to the aquifer, whence it can easily flow into the sea. […]
- [Footnote 292] Toru Ebisawa, 2013, Bulletin of the Citizens’ Nuclear Information Center, 465: 12. J. Kanda gives an earlier estimate of 160 PBq [of Cs-137], as of May 2011, Ocean Policy Research Foundation, Kaiyo Hakusho 2012 [annual report in Japanese], p. 45. Seizando-Shoten Publishing, 2012.
- The Atomic Energy (Journal Volume 112, Issue 3), July 2012: Estimation of radionuclide emission during the March 15, 2011 accident at the Fukushima-1 NPP
“According to estimates made by the present authors, the following radionuclides entered the atmosphere on March 15, 2011 (PBq): ~400 iodine, ~100 cesium, and ~400 inert gases.”
“While the amount of radioactivity released into the environment in March 2011 has been estimated as between 10 percent and 50 percent of the fallout from the Chernobyl accident, the 400,000 tons of contaminated water stored on the Fukushima site contain more than 2.5 times the amount of radioactive cesium dispersed during the 1986 catastrophe in Ukraine.”
(85 Pbq x 2.5 = 212.5 Pbq) => > 212 PBq Cs-137 in just the water tanks alone
This rather pathetic August 7, 2013 National Geographic article (including WHOI’s Buesseler citing the 15 PBq Cs-137 total from way back, as well as making totally inappropriate comparisons to external radiation sources such as X-rays (which he did the other day again)), interestingly also included:
“The tanks (on the plant site) have 100 times more strontium than cesium, Buesseler said.”
Going on the CNN report that came out later, above, that would imply 212 PBq x 100 = 21200 PBq of Sr-90. Really? That compares to 1 Pbq of Sr-90 from Chernobyl. If it holds true, that would make Fukushima, in terms of radioactive Strontium, more than 20,000 times Chernobyl. Just in the water tanks alone…
But, enter PBS, they bring it back down the next day, citing someone else…:
PBS NewsHour, on Aug. 8, 2013, puts the estimate of Strontium at “30 times the Cesium”, quoting Arjun Makhijani, nuclear fission engineer, president of the Institute for Energy and Environmental Research:
“So, so far, we have been concerned about an element called cesium, cesium 137 and 134, which is radioactive. But now they have found strontium-90, which is much more dangerous, at levels that are 30 times more than cesium.”
Okay… (30 x 212=) 6360 Pbq then, still more than 6000 times Chernobyl’s Strontium-90 release.
Now, even if we were to go by the long-proven incorrect earliest TEPCO estimate of some 15 PBq of Cs-137 from Fukushima and multiply that by just 30, not 100, then we’re still looking at Fukushima having released AT LEAST 450 times the Strontium released by Chernobyl. If it makes it into one’s body, its effect over time is often bone cancer and Leukemia.
As far as Iodine-131, seems that one may have been less than Chernobyl, I don’t know. It was about 1/3rd Chernobyl at 511 PBq of I-131. My map Fukushima versus Chernobyl fallout map comparison for I-131 also hinted at the possibility that Fukushima’s I-131 release was less than Chernobyl’s, but so much data has proven to be vastly underestimated, so who knows? Maybe it was closer to about equal? In terms of Iodine-131 it must by now be well over the originally reported, especially since fissioning apparently hasn’t fully stopped yet. But I didn’t find much more on that. Comments welcome.
There was also this November 17th, 2011 ENENews Report mentioning: “Absorbed radiation dose of iodine-132 was 10 times higher than iodine-131 in Northern Japan after Fukushima meltdowns — Plus iodine-132 is 9 times more ‘effective’ at irradiating thyroid.”
To summarize, it looks like Fukushima is,
- in terms of radiocesium, 3 to over 4 times Chernobyl;
- in terms of radiostrontium it released more than 400 times Chernobyl (or over 20,000 times, depending on which statements reflect on which data, see Afterthoughts);
- In terms of Iodine-131 it must by now be well over the originally reported “1/3rd of Chernobyl” reported early on. (see above)
- In terms of Noble gasses, like Xe-133, it’s off-the-charts much more than Chernobyl released. See HERE, for instance. These old numbers have only gone up.
CONCLUSION: In any case, given all the revelations this summer (2013), it seems that overall, it is now fair and factual to state: Fukushima is over 4 times Chernobyl. (But much of that luckily, thanks to the hard work of the workers on site, has not made it into the open environment.)
Any news outlet that still uses that line “worst since Chernobyl” is still pathetically trying to maintain the old TEPCO lie that it this is not what we now know it is: the worst nuclear accident in history. Period. Not “since Chernobyl” (as that implies Chernobyl was worse), but in the history of the nuclear industry.
- Already on May 16, 2011, I passed along the news: “Strontium-90 Detected in Waters Near Fukushima Power Plant“.
- June 19, 2013, NBC World News reported that “Radioactive Strontium-90 found in groundwater near Fukushima nuclear reactor“
- Although what has actually leaked into the Pacific seems not fully understood, on the upside, it appears that most of the Strontium-90, as well as most of the Cesium-134 & 137 is currently stored in those water tanks on site. Short-term as all of this is, TEPCO deserves some credit for their efforts.
Comparing Fukushima with fallout from nuclear bombs:
Over 20,000 times the Sr-90 of Nagasaki? Over 3000 times the Cs-137 of Hiroshima?
- If you combine the above CNN‘s statement (2.5 x cs-137 Chernobyl = 2.5 x 85 PBq = 212.5 PBq Cs-137 (in water tanks)) with the above WHOI‘s statement (Fukushima Sr-90 = 100 times Fukushima Cs-137 (in reference to those tanks)), then there’s 21250 PBq Sr-90 in those tanks.
- The ratio 1:87 for Sr-90 compares Nagasaki with Chernobyl [Chernobyl released 87 times Nagasaki’s Sr-90 release]; then simple math brings me to the stunning finding that: in terms of Sr-90, Fukushima = 21750 times the Nagasaki A-bomb Strontium fallout. (Conservative estimate, as the ratio was based on a ground blast, which would release more). And, for Fukushima, that’s also a conservative estimate, as those numbers are for the water storage tanks, not for the whole.
- Comparing Fukushima to Hiroshima in terms of Cesium: If using the data from the recent World Nuclear Industry Status Report 2013, published in July 2013, then Fukushima’s released Cesium-137 stands at 276 PBq (about “2.5 times Chernobyl’s cesium release” is stored in the water tanks or in the ground locally); that’s 276000 TBq (see my Radiation Units page for units and conversions), divided by Hiroshima’s 89 Tbq Cs-137, then that gives us the stunning fact that, in terms of Cs-137, Fukushima is now 3101 times the Hiroshima A-bomb Cesium fallout. Although, again luckily, much of that remains stored on site. I guess the newspapers are running a little behind. Last time I read a comparison like that was two years ago, when they could still pretend that Fukushima caesium leaks ‘equal 168 Hiroshimas’ (UK Telegraph Aug 25, 2011)
- PS: For decent news sources (that tend to weed out the utter nonsense), see my: Nuclear News page. See also more options in the ‘Nuclear’ tab above.
- If you’re looking for reliable news, then websites to be avoided for sure are “Natural News”, “National Report”, “Examiner” and places that repeat anything alarmist, such as “Before It Is News”.
[last updated Sept. 6, 2013; couple small edits Sept 12, 2013]