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Japan Earth Stats

One Trillion Bq Released By Nuclear Debris Removal At Fukushima So Far 190

AmiMoJo writes The operator of the damaged Fukushima Daiichi nuclear plant says more than one trillion becquerels of radioactive substances were released as a result of debris removal work at one of the plant's reactors. Radioactive cesium was detected at levels exceeding the government limit in rice harvested last year in Minami Soma, some 20 kilometers from Fukushima Daiichi. TEPCO presented the Nuclear Regulation Authority with an estimate that the removal work discharged 280 billion becquerels per hour of radioactive substances, or a total of 1.1 trillion becquerels. The plant is believed to be still releasing an average of 10 million becquerels per hour of radioactive material.
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One Trillion Bq Released By Nuclear Debris Removal At Fukushima So Far

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  • by Anonymous Coward on Thursday July 24, 2014 @09:05PM (#47527811)

    So....is that bad?

    • Re: (Score:2, Funny)

      by Anonymous Coward
      It's terrible. We have, what, seven billion people on earth? Now there's a population explosion and all of a sudden we have a trillion Scott Becquerels. They can't create Quantum Leap reboots fast enough, and everyone is scrambling to keep all Star Trek-related scripts away from them.
    • by gweihir ( 88907 )

      Depends. If you are a nuclear apologists, it is irrelevant. If you want real numbers, its a few 1000 more cases of cancer that unfortunately cannot be identified individually as having been caused by this.

    • Not as bad as one million trillion microbecquerels.

      Oh, wait....

    • So....is that bad?

      One becquerel = 27 pico curie.

      One trillion becquerel = 27 curie.

      Sounds a lot less frightening now.

      However, one curie is an awful lot of radiation. You wouldn't go near that. On the other hand, becquerel and curie are measures of "radiation per hour", so "1 trillion becquerel released" doesn't make sense.

  • by Anonymous Coward on Thursday July 24, 2014 @09:07PM (#47527821)

    in miles per hour. No but seriously, Bq is disintegrations per second. It's a convenient way to quantify radiation if you have one isotope or it's contained in a small area, but is absolutely ass for a situation like this.

    • by msauve ( 701917 )
      Bq seems a fair measure to me. It's a measure of radioactivity. Would you prefer pounds (or kilograms) of X, with no measure of the rate X is releasing radiation?

      To follow your analogy, if the concern is how fast something travels,then MPH is a reasonable measure.

      Time (rate) seems an important component of the measure to me. What SI unit do you propose they use?
      • While it's not a good thing, using Becquerels is a convenient way to make something sound worse than it actually is. It's 27 Curies, which is about 0.18% of the activity of the sources they use for some gamma sterilization machines (which can be around 15000 Curies or 555,000,000,000,000 Bq). Now that is a scary amount of radiation.

        • by msauve ( 701917 )
          The Curie is not an SI unit. It is, however, locked to the Becquerel by a fixed ratio. They measure exactly the same thing, so in what way do you claim Bq are "bad?" The GP seems to want a measure of disintegrations without regard to time, which makes zero sense. It's like claiming you did work or expended energy when trying to lift a 1 Kg rock with 1 N of force.
          • by Artifakt ( 700173 ) on Thursday July 24, 2014 @11:26PM (#47528543)

            Even though they measure the same thing, the Becquerel is a very, very small unit. If somebody was talking about the risk of a dam breaking, and used the cubic centimeter for measuring the volume of water behind that dam, perhaps with a note that a single cc of water can killl a person if they choke on it just right as a justification, wouldn't you still prefer a unit such as gallons, or cubic feet or cubic meters, Wouldn't that be better in helping asses the real consequences of a dam failure even though we are measuring the same thing? Or wouldn't it be better to give information on just how many acres downstream would be flooded and how many people live on that floodplain, even though that's all a very different kind of measurement? There are plenty of cases where either a similar measurement that uses units more in keeping with the situation or a measurement of something different may either or both be better.
                      Using SI units is a good thing overall, but what if those units are many orders of magnitude outside of the thing they were designed to measure and there's a non-SI unit that isn't? Or, what's the point in preferring Km./liters over miles/gallon if we are talking about how much fuel it took to send Voyager 1 outside the heliopause? Neither one is very useful when we are not exactly sure just where the edge of the solar system is, or how to measure it, and Voyager will keep on coasting many light years farther in the end, if its trajectory even has an end in the lifetime of the universe.
                        I see using becquerels in this case as similar to someone being opposed to a government project, so they give how much it costs in the currency of some nation currently undergoing hyperinflation, so the project costs a bajillion, bajillion, Saganillion Elbonian Smerdlaps, That's not the same thing as writing about the US economy for a European audience and converting to Euros, or writing about the European economy for Japan and converting to Yen. Even though we know a conversion rate for the uints, and it's fixed as of a given date,,using some units for currency could still be an attempt to make the numbers sound so large they prejudice the average reader more than they inform. You should look at what level of information the average person reading an article from that particular source will have in deciding whether a difference of units is simply a difference or if there's some intent to mislead - and since you asked it as in what way X is :bad?", hopefully we can agree attempts to mislead are bad.

            • Oooops! I would drop an 's' from assess and make it asses. Why just mispell something when you can make what someone will probably call a Freudian slip, after all? Please excuse me.

            • by AmiMoJo ( 196126 ) *

              The units are not that important, what matters is the relative numbers. The point of the story is that TEPCO is failing to prevent the release of radioactive material from the plant in enough measure to contaminate nearby crops and make them worthless. Relatively speaking the amount of released material is lower now, but expected to rise once they start further decommissioning work.

              In this case the unit used by TEPCO and the government is Becquerels, and there has been a great deal of discussion about it in

          • Perhaps I should have been more clear. I think it's a bad unit to use, because it's being used to purposefully scare people. The large order of magnitude of the measured values is misleading. Saying 1 Trillion Becquerels makes it sound a lot worse than it actually is.

            • by msauve ( 701917 )
              The article was reporting on a relative increase, and actual harm. Radioactive material is normally being released to the atmosphere from the site at a rate of 10 MBq / hr. The article points out that there was some recent work which released it at a rate of 280 GBq / hr, over a period of 4 hours. That's 28,000X the normal rate (over 3 years' worth), and it resulted in radiation contaminated crops 20 km away.

              You're making it sound a lot better than it actually is.
              • by msauve ( 701917 )
                That should be "over 3 years worth per hour..."

                1.12 TBq would normally take 112000 hours (over 12.7 years) to be released.
      • by fnj ( 64210 )

        MPH is a reasonable measure ... What SI unit do you propose they use

        Meters per second springs to mind. Base units make the most sense.

        • by Altrag ( 195300 )

          Just measure in Planck units. Don't get much more base than that!

          I think his issue wasn't in the units but in the dimensional analysis. Its like saying "I walked a total of 3mph!" Uhhh.. total? You can't really compute a total of "X per unit time." At least not in any way that makes physical sense. You could add up all of the individual units (or integrate over it if you want to go continuous) but then you're effectively removing that "per unit time" bit and the original statement still doesn't make s

      • by Solandri ( 704621 ) on Friday July 25, 2014 @01:16AM (#47528971)

        Bq seems a fair measure to me. It's a measure of radioactivity. Would you prefer pounds (or kilograms) of X, with no measure of the rate X is releasing radiation?

        It's a bad unit to use in this context because it's a measure of individual atomic decays per second. It's kinda like you asking me how far you have to walk to get to the nearest bus stop and me telling you the distance in angstroms. The scale is just completely devoid of any common reference frame for the number to be intuitively useful (not that most people have a common reference frame for radioactivity). That's why Bq is commonly used by people trying to scare the public about radioactivity - when you're talking about a lot of material like, oh, a field, it results in really, really big numbers.

        Let's put it this way. A block of soil one square mile by 1 foot deep (790,000 m^3) has a natural radioactivity of 653 billion Bq [isu.edu]. If they excavated 1.1 trillion Bq of radioactive material from Fukushima, then they removed about as much radioactive substances as is naturally contained in 1.7 square miles of soil one foot deep. Of course the piece of information that we're missing (and no it's not in TFA) is how much volume of material they removed. If we knew that, we could come up with a ratio and say "Ah hah! The stuff they removed is x times more radioactive than the natural radioactivity of dirt!"

        • by MrL0G1C ( 867445 )

          It's worse than that it's like asking someone how far the bus stop is and the person answering 10mph.

          I can't help but notice that the lack of any meaningful measurements was used by several slashdotters to say the radiation was low and then several modders conveniently overlooked the fact that their math made no sense whatsoever and modded them up because the message is pro-nuclear.

        • by msauve ( 701917 )
          "It's kinda like you asking me how far you have to walk to get to the nearest bus stop and me telling you the distance in angstroms."

          No, it isn't. Angstroms are not an SI unit. It's more like asking how far the next town is, and getting an answer in meters instead of km.

          "The scale is just completely devoid of any common reference frame for the number to be intuitively useful"

          So, the public has an intuitive understanding of Curies? OK.
          • by Rich0 ( 548339 )

            "It's kinda like you asking me how far you have to walk to get to the nearest bus stop and me telling you the distance in angstroms."

            No, it isn't. Angstroms are not an SI unit. It's more like asking how far the next town is, and getting an answer in meters instead of km.

            More like nanometers. Bq is measuring events on an atomic scale. nm is actually a little too big, but it is getting close.

            When diluted into even a pond (let alone an ocean) trillions of Bq aren't actually all that much. People eat about 9 trillion Bq of potassium each year from bananas alone, so if humanity collectively drank the entire pacific ocean they might double their dose (and have one heck of a sewer bill).

            • by msauve ( 701917 )
              The headline here was way off - this was over 1 TBq being release to the atmosphere recently over a single 4 hour period. It resulted in radioactive contamination of crops 20 km away. The total amount of radioactive material released from the site is obviously much, much greater.
              • As everyone else has said a milion times already, Bq is not a quantifiable "amount" of radiation, its a rate. You cannot release x Bqs in y period of time, any more than you can travel 50mph in 2 hours. You could say "I travelled 100 miles", or "I am currently travelling at 50mph", or "over 2 hours I averaged 50mph", but mph is not , itself, a quantity. Same with Bq.

                From Wikipedia [wikipedia.org]
                One Bq is defined as the activity of a quantity of radioactive material in which one nucleus decays per second.

                • by msauve ( 701917 )
                  Oh, bullshit.

                  You really have no clue what you're talking about. When one says X Bq were released, the meaning is that radioactive material which releases radiation at that rate has been released.
                  • No, thats not what theyre saying:
                    On Wednesday, Tokyo Electric Power Company presented the Nuclear Regulation Authority with an estimate that the removal work discharged 280 billion becquerels per hour of radioactive substances, or a total of 1.1 trillion becquerels.
                    Theyre treating Bq as if its a quantity of radiation. They dont know what theyre talking about. They multiplied 280 billion by 4, and ended up with 1.12 trillion-- which isnt how rates work.

                    • by msauve ( 701917 )
                      You're in the "slow classroom," aren't you?
                    • Except that they dont list what material they are talking about, and anyone who has done 5 minutes of research know that units like the Sievert and the Gray are far more useful when talking about human exposure, because they compensate for the different sorts of radiation and their effects.

                      Saying "1 curie" doesnt tell you much if you dont know what its 1 curies worth of, or how much total matieral we're talking about.

        • by gewalker ( 57809 )

          Conveniently, there is an even better comparison. You have to disperse all of the radioactive soil into the air to make a similar comparison. We don't actually pump soil into the air though. We do however burn coal.

          Webpage [blogspot.com] According to the National Council on Radiation Protection and Measurements (NCRP), the average radioactivity per short ton of coal is 17,100 millicuries/4,000,000 tons, or 0.00427 millicuries/ton. This figure can be used to calculate the average expected radioactivity release from coal co

      • Would you prefer pounds (or kilograms) of X, with no measure of the rate X is releasing radiation?

        Yes, absolutely. I can look up what kinds of radiation X emits and its specific activity.

  • by Anonymous Coward

    Can someone with experience comment on whether that is a lot or not? Obviously it's not what anyone wants released into the environment, but as a non-becquerel expert it's hard to have some sort of relevance.

    Please no car analogies though.

    • Re: (Score:3, Informative)

      by calidoscope ( 312571 )
      Not that much. A typical Tc99m scan involves injection a bit over a billion (10E9) bq per person, albeit half life is only 6 hours. Reminds me of a "warning sticker" for a CB radio - "Danger 5,000 milliwatts".
      • by AmiMoJo ( 196126 ) *

        This is a common misunderstanding of the way the released radioactive particles affect humans. The material from Fukushima bioaccumulates inside the body. It has already been found to be doing this in wildlife and people near the plant. Once inside the body's organs it can remain for decades, slowly damaging the DNA and leading to cancer. Things like x-rays are one-off events that deliver a single dose, much of which is blocked by tissue (that's why parts of the image are dark), this stuff bypasses all the

        • The material from Fukushima bioaccumulates inside the body.

          Nothing about being "from Fukushima" has any affect on what the material does. Its makeup does. Is it radioactive Iodine? Potassium? Thorium? Uranium? Cobalt-60?

  • by Anonymous Coward

    Why not list what Sv of exposure people might be exposed to instead of a measure like Bq which produces large, meaningless numbers for headlines?

    You don't even want to know how many Bq the Sun releases, but what matters is who is exposed to what danger.

    • by sjames ( 1099 )

      Because that wouldn't have people ripping their hair out in a panic.

      • by msauve ( 701917 )
        In Fukushima, radiation rips hair out for you!
  • Since the becquerel has units of reciprocal seconds and one hour is 3 600 seconds, the number quoted 10 as million becquerels is 36 000 million with no units. Hmmm...?
    • Since the becquerel has units of reciprocal seconds and one hour is 3 600 seconds, the number quoted 10 as million becquerels is 36 000 million with no units. Hmmm...?

      Yes and no.

      Bq is the measure of radioactive events per second. Multiply that by time and you just get a (unitless) count of the number of events.

      Except they are dividing it by time giving events/s^2. That indicates that the number of events per second is increasing. As in things are getting more radioactive.

  • I was kind of keen on visiting Japan during the fall months. I have no idea how this impacts my decision.

  • A trillion Bq is a fairly small number, especially when spread over a large area. That's pretty insignificant.
    • A trillion Bq is a fairly huge number, especially when spread over a very small area. That will cook you like fried chicken exposed to the afterburner on an F18.

      Of course they didn't give us any idea which of our both-true statements reflects reality.

      Without context is no.
      • by AC-x ( 735297 )

        1 trillion Bq is about 0.3g worth of Cs-137 [wolframalpha.com].

        You wouldn't want to swallow it, but it's not going to be "cooking" anything.

      • There are two types of comments in this thread.

        * Comments by people providing definitions for what a Bq is, talking about equivalent measures, giving conversion forumulas, and providing hard facts; generally these are saying that the number is either irrelevant, and / or not really that big.

        * Comments by people who are being quite vague, and warning of various undefined threats to various undefined organs because of how big the number is.

        Which type of comment do you find more credible?

  • by Irate Engineer ( 2814313 ) on Thursday July 24, 2014 @10:34PM (#47528335)
    (holds pinkie to corner of mouth).."one *TRILLION* Becquerel!" (uproarious laughter from nuclear engineers)
  • For your information, an average human body contains natural radioactive isotope of potassium - 40K. Every second there are approx. 3000 decays (Bq) of that isotope in your body. It means that every man is approx. 9 billions Bq "on release" per year. 40K emits 1460 keV gamma-ray (that easily goes out of your body) in about 10% of decays, the rest ends in beta-particle only, that stays inside. That's one of the problems of measuring release in Bq, which is not a good idea. Anyway, your one trillion Bq is e
  • by Required Snark ( 1702878 ) on Friday July 25, 2014 @01:37AM (#47529063)
    Now that the Slashdot Pundits have made fun of a number, here's what's happening in the real world.

    According to researchers, monkeys in the vicinity of Fukushima City had detectable levels of radioactive cesium in their muscles, while the northern monkeys did not. Researchers also found that the Fukushima simians had significantly lower white and red blood cell counts compared with macaque troops almost 200 miles away.

    The researchers suggested their findings mirrored studies conducted on human health impacts following the Chernobyl disaster, where researchers found decreased blood cell counts in people living in contaminated areas.

    http://www.latimes.com/science/sciencenow/la-sci-sn-fukushima-monkeys-20140724-story.html [latimes.com]

    The Chernobyl site is in the process of having a New Safe Confinement [wikipedia.org] structure built, which will keep radioactive material from the disaster site from entering the environment for 100 years. Once it is in place some of the radioactive material will be broken up and moved to long term buried storage.,

    In contrast, one of the articles states "The plant is believed to be still releasing an average of 10 million becquerels per hour of radioactive material." The quoted 1.1 trillion BQ figure was the result from recent debris removal.

    Up to 1.12 trillion becquerels of cesium was dispersed last summer as debris was removed from the battered building of reactor 3 at the Fukushima No. 1 nuclear plant, with tainted rice later being found in Miniamisoma, Fukushima Prefecture, according to Tokyo Electric.

    The amount of cleanup and debris handling remaining is immense compared to the work done in this last operation. This means that the impact of future work will be proportionally larger.

    Beyond that, the three damaged cores are still not stable or safe. There is no solid information on the state of cores, or even if the core material is in the containment structure. At least one of the cores is believed to have suffered a complete meltdown and become corium [wikipedia.org].

    The already severely damaged reactors are still at risk for future earthquakes, tsunamis and typhoons. Any one of these events could result in another large scale radiation event. The Fukushima disaster is not necessarily over. It's just less active.

    So go on and giggle over a number. It shows that you have the collective intelligence of a retarded 11 year old.

    • by AmiMoJo ( 196126 ) *

      Thanks. The comments on every single nuclear story on Slashdot seem to miss the point entirely. The units are just a way to measure the relative efficiency of the work being done to prevent leakage. The effects are observable, there is no need to guess based on the numbers. This is apparently too complex for most commentators to understand :-(

    • FUD, now in "patronizing" flavor.

      To suggest that critiquing a stupid unit of measure is somehow trivializing the problem is itself a strawman.

      If I said that I'm 1,930,400,000,000 picometers tall, people SHOULD mock me for using a stupid unit of measure. When people are primed to overreact to an event like Fukushima and then confronted by a number in public reporting that uses just such an inappropriate unit of measure, one can either mock the report for being foolish, or condemn it for being deliberately i

    • The story about Chernobyl is far from clear. See, for example:

      http://unconventionaltravel.co... [unconventionaltravel.com]
      http://www.sciencedaily.com/re... [sciencedaily.com]

      And, in my view most impressive:

      http://www.bbc.co.uk/pressoffi... [bbc.co.uk]

      Note that human beings are mammals; so, if other mammals thrive in an area, presumably human being would too (if not excluded by regulations).

  • Not to trivialize Fukushima Daiichi but the current release of 10 MBq/h could be compared to the single dose of 33 MBq my baby daughter has injected last week. I was not happy with that because it seemed that the examination was for no useful purpose.

    Still, the Fukushima mess has convinced me that nuclear power is a too dangerous path to thread. Unfortunately.

  • by sjwt ( 161428 )

    Now lets use my favourite dosage level, and all radiation related matters should be in the everyday standard of BED (Banana Equivalent Dose)

    We are talking about an exposure of 8,461,539 KG's of Bananas. Or about One 17th the level that Bananas expose humans to in a year. (@140Bqs per KG)

    Did you know that Humans are radioactive and rated at about 100Bqs per KG, so we are talking about a release of radiation equal to about 11 million KGS of ppl or less than what the ppl in a city with around 180,000 populatio

  • Becquerels are tiny units. In the first 3 months after the accident 14 Quadrillion (1.5x10^16) becquerels were released. For comparison Chernobyl released 14 Quintillion (1.4x10^19) becquerels in total. (source [nature.com]).

    Compared to that, 1 trillion (1.1x10^12) becquerels is a big improvement in rate of release and according to Wolfram Alpha [wolframalpha.com] represents around 300mg of Cs-137.

  • 1 trillion becquerels is 27 curies, or the radioactivity of 27 grams of radium-226.
    It's also 66.6 times less than Ted Sprague's base output in Heroes.

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