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Anti-Nuclear Quote of the Day.

with 8 comments

Doctors now estimate that about 160,000 children below the age of seven living in the Ukraine in radioactively contaminated areas are at risk of developing thyroid cancer from radioactive iodine 131.

No, there are no children in the Ukraine below the age of seven who are at an elevated risk of developing thyroid cancer due to the Chernobyl accident. In fact, there are no people in the Ukraine, or Belarus, below 19 or so years of age who are at any increased risk of developing thyroid cancer due to the Chernobyl accident.

Why? Because they were never exposed to any radioactive iodine-131 source term.

I-131 has a short half-life: 8 days.

The Chernobyl Forum puts the release of I-131 from Chernobyl at 1.8 EBq – that’s 1.8 x 10^18 Bq; a hell of a lot of radioactivity. Because of what happened to Chernobyl Unit 4, and because Iodine is so volatile and reactive, that represents nearly the entire amount of I-131 in the nuclear fuel.

1 year after the disaster, 0nly 0.88 microcuries of I-131 remained in the environment, undecayed. (I-131 has a specific activity of 1.2 * 10^5 Ci/g).

After 1.83 years – one year and 10 months – there is a 90% chance that there is not one single I-131 atom left undecayed. This is all rather straightforward to calculate – I won’t bore you all with it, unless somebody wants to challenge my calculations – feel free.

There are no children being exposed to I-131 from Chernobyl today. The only people with an increased risk of thyroid cancer are those who were there in 1986-1987, during and immediately after the accident, when the I-131 was present.

Written by Luke Weston

January 21, 2008 at 8:55 am

8 Responses

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  1. Where are you getting these quotes?

    bryfry

    January 21, 2008 at 11:05 am

  2. Well, that one was from Helen Caldicott’s autobiography.

    Admittedly, I can’t recall when it was published – if it was within 8 years or so of Chernobyl, which it might have been, then it’s a not unreasonable statement.

    enochthered

    January 21, 2008 at 1:59 pm

  3. I believe it was published in 1996.

    Sovietologist

    January 21, 2008 at 4:44 pm

  4. I’m a believer in making the extra effort to understand as playing my part in communication, so in my world you’ve picked on the wrong aspect of this quote to criticize, although Caldicott’s mangled constructions do lend themselves to misinterpretation.

    Let’s assume that the reference was dated from say 1988, or that “below the age of seven” referred to the age of the children at the time of the reactor’s destruction. Even then, being “at risk of developing thyroid cancer” is not the same as actually developing it. And even with thyroid cancer, the probability of completely successful treatment is very high, better than 99%. So if this is one of the “strong” arguments on how terrible nuclear power is, it’s still very weak.

    Every child in the world is “at risk” of being struck by lightning; the useful and intersting question is, how many will actually be hit?

    Joffan

    January 21, 2008 at 8:45 pm

  5. Citation:

    [quote]
    The only people with an increased risk of thyroid cancer are those who were there in 1986-1987, during and immediately after the accident, when the I-131 was present.[/quote]

    Your “only” is a hit in the face of all the victims. Your “only” shows that your’re not a medic and this is your problem.

    I’ve seen children in contaminated areas in Belarus, with benign thyroid cancer.

    So, what does that mean?
    It means a lifelong hormone therapy, optional extraction of the paratyroid.
    Not so easy for the poor people living in contaminated areas, isn’t it?

    But this is the greatest lack of knowledge and a sea of ignorance, citation:

    [quote]Every child in the world is “at risk” of being struck by lightning; the useful and intersting question is, how many will actually be hit?[/quote]

    This is a barbarian view, a kind of substantial equivalent and an attack on children with thyroid cancer.
    Even the IAEA had to accept thyroid cancer as a cancer caused by radiation, cause they couldn’t deny it any longer – the numbers were too high.
    But still today they AND YOU try to ignore every scientific proven links between disease and radiation.

    This is one of the worlds worst propaganda blog sites. It is neither scientific nor is it ethic.

    regards,

    T.

    tekknorg

    August 10, 2008 at 1:36 pm

  6. And, btw the way: 72% of Chernobyl fallout with I-131 went down on Belarus.
    Millions were affected.

    Answer!

    regards,
    T.

    tekknorg

    August 11, 2008 at 4:47 pm

  7. Can you show me the calculations you did to derive the 1.83 year answer you got with Iodine-131? Also how did you derive the 90% chance that there is not one single Iodine-131 left?

    Sincerely “Just another curious High School student”

    HS Student

    November 14, 2008 at 8:07 pm

  8. Sure thing, HS Student.

    In the beginning, there is 1.8 x 10^18 Bq of I-131.

    The specific activity of Iodine-131 – how much radioactivity per gram of material – is 1.2 x 10^5 Curies per gram. 1.2 x 10^5 curies per gram is 4.44 x 10^15 Bq per gram, and therefore, the total mass of I-131, initially, was 405.4 g.

    405.4 g of iodine is 3.195 moles, and therefore that’s 1.92 x 10^24 atoms of iodine. The half-life of I-131 is eight days. Now, we can consider the exponential decay characteristic of radioactivity:

    0.1 = 1.92 * 10^24 * 2^(- t / 8 days)

    Saying that “there is a 90% chance that there is not a single I-131 atom left” is the same thing as saying that there are 0.1 atoms remaining, in the context of the exponential decay mathematics. Of course, you can’t have 0.1 of an atom – this exponential decay curve becomes quantized when you get down to the scale of very small numbers of atoms.

    Now, we need to fiddle with the algebra and solve the above expression. When you do so, you change the base of the logarithm from base 2 to a standard base, and you have something like the following to compute:

    t = 8 days * log((1.92 * 10^24) / 0.1) / log(2)

    Calculate that, and you ultimately end up with an answer of 1.83 or 1.84 years or so, depending on how accurately the calculation is performed.

    Luke Weston

    November 16, 2008 at 5:19 am


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