[ RadSafe ] RadSafe Digest, Vol 1445, Issue 1

Mon Nov 18 13:49:54 CST 2013

I agree that there are big problems with the article (I've thought of
getting involved with writing and editing wiki articles, but down that
road madness lies).

The biggest is that much of the "total" activity is short half-life
isotopes.  For example, all the I-131 is gone.  While one might discuss
the effect that it might have, or might have had, on people who were
exposed to it in the first couple months, present amounts do not factor
into anything, because there isn't any left.  This is true with most of
the isotopes that made up most of the activity during the initial
release.

Half the Cs-134 is gone.  Doesn't matter where it got off to; half of it
has decayed away.  

Even when phrases like "Bq per liter" are used, almost never is it a
particularly relevant measure when trying to calculate health effects.
If you have GBq/l in water leaking out of the plant at Fukushima, I
would strongly advise against drinking it or bathing in it (NOTE: to be
fair, I always advise against drinking or bathing in water seeping out
of any ruined industrial facility).  However, once  the millions of
liters have entered the ocean and been diluted by a factor of just short
of infinity, I become less concerned (I still would advise against
drinking it, because it is salt water, and that isn't good for you).  

I wish you the very best of luck in making this make sense to the
general public.

-----Original Message-----
From: radsafe-bounces at health.phys.iit.edu
[mailto:radsafe-bounces at health.phys.iit.edu] On Behalf Of Rick Maltese
Sent: Monday, November 18, 2013 10:47 AM
To: radsafe at health.phys.iit.edu
Subject: Re: [ RadSafe ] RadSafe Digest, Vol 1445, Issue 1

Thanks Mike. That does help clarify to me what is involved. I was hoping
to provide a response to people who have seen reports of seawater being
affected by Fukushima.

The wikipedia article
http://en.wikipedia.org/wiki/Radiation_effects_from_the_Fukushima_Daiich
i_nuclear_disaster

"On 24 May 2012, more than a year after the disaster, TEPCO released
their estimate of radiation releases due to the Fukushima Daiichi
Nuclear Disaster. An estimated 538,100 terabecquerels (TBq) of
iodine-131,
caesium-134 and caesium-137 was released. 520,000 TBq was released into
the atmosphere between 12 to 31 March 2011 and 18,100 TBq into the ocean
from
26 March to 30 September 2011. A total of 511,000 TBq of iodine-131 was
released into both the atmosphere and the ocean, 13,500 TBq of
caesium-134 and 13,600 TBq of
caesium-137.[55]<http://en.wikipedia.org/wiki/Radiation_effects_from_the
_Fukushima_Daiichi_nuclear_disaster#cite_note-55>
In
May 2012, TEPCO reported that at least 900 PBq had been released "into
the atmosphere in March last year [2011]
alone"[56]<http://en.wikipedia.org/wiki/Radiation_effects_from_the_Fukus
hima_Daiichi_nuclear_disaster#cite_note-56>
[57]<http://en.wikipedia.org/wiki/Radiation_effects_from_the_Fukushima_D
aiichi_nuclear_disaster#cite_note-57>
up
from previous estimates of 360-370 PBq total."

I think you see the problem. They are using the numbers as quantity
rather than rates. I am assuming we should be saying "per kilogram"
after each of the amounts mentioned. I think the article needs to be
corrected and that what has been reported needs fixing so the numbers
make sense. We would need to know how many grams of each element was
released to understand the meaning of the numbers. Am I correct?

It is unfortunate that this is rarely explained. If the quantities
released are less than a kilogram then the figures are very misleading.
The general public does not see it as a rate. But the article gets it
right in several other places where they say "per kilogram"

Do I have this correct?

> Today's Topics:
>
>    1. Re: RadSafe Digest, Vol 1444, Issue 1 (Rick Maltese)
>    2. Re: RadSafe Digest, Vol 1444, Issue 1 (Brennan, Mike  (DOH))
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Mon, 18 Nov 2013 02:01:52 -0500
> From: Rick Maltese <malteserick at gmail.com>
> Subject: Re: [ RadSafe ] RadSafe Digest, Vol 1444, Issue 1
> To: radsafe at health.phys.iit.edu
> Message-ID:
>         <CAPpaKi5Xq-XA--tWV_1YFznzrSfrnnYT=iu1oL5Suet5=
> qsqJQ at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Can anyone help me put together a paragraph that explains Becquerels 
> to the layman. I am creating a document to help explain radiation. 
> Especially in relation to scary media about Fukushima. You can take a 
> look at what I've got so far.
>
>
>
> http://deregulatetheatom.com/reference/radiation/quick-radiation-refer
> ence-guide/
>
>
> If there is also a graphic I would be very grateful.
>
>
> Rick Maltese
> 647-379-9655
>
> webcompose.ca  webdesign services
>
> leadsheetz.com  music services - transposing, composing, teaching etc
>
> rickmaltesemusic.com  piano gig page
>
>
> ------------------------------
>
> Message: 2
> Date: Mon, 18 Nov 2013 09:43:13 -0800
> From: "Brennan, Mike  (DOH)" <Mike.Brennan at DOH.WA.GOV>
> Subject: Re: [ RadSafe ] RadSafe Digest, Vol 1444, Issue 1
> To: "The International Radiation Protection (Health Physics)
>         MailingList"    <radsafe at health.phys.iit.edu>
> Message-ID:
>
<37C41083D3480E4BBB478317773B845D0D5CE6B3 at dohmxtum31.doh.wa.lcl>
> Content-Type: text/plain;       charset="us-ascii"
>
> How is this:
>
> Radioactive material is radioactive because atoms change, or "decay", 
> from one element into another.  The unit for measuring this decay in 
> the International System of Units (SI, or what most Americans think of

> as
> "metric") is the Becquerel (Bq).  One Becquerel is equal to one decay 
> per second.  Because we are often interested in amounts of 
> radioactivity much larger than that, we use the standard set of 
> prefixes (mega-, giga-, etc.) when talking about activity.
>
> There are a couple of things to keep in mind when talking about 
> activity, in Bq or other units, because they work differently than, 
> say, miles per hour or pounds per square inch.  One is that the 
> instruments used to measure activity usually can measure only certain 
> types, and only certain energies of radiation.  Even for the type and 
> energy it can measure it only measures the radiation that hits the 
> detector (and not the radiation that goes in other directions), and 
> only a portion of that.  It is important to know what material is 
> being measured, and how it is being measured.
>
> Another thing to keep in mind is that when an atom decays and changes 
> into a different element, it is no longer an atom of the original 
> element.  It may not be radioactive anymore, or it may be radioactive 
> in a different way.  If the half-life of the original radioactive 
> material is long decay might not affect the number of Bq in the amount

> of time we care about, but if the half-life is short the number of Bq 
> could change so fast that you need to keep calculating new numbers.
>
> -----Original Message-----
> From: radsafe-bounces at health.phys.iit.edu
> [mailto:radsafe-bounces at health.phys.iit.edu] On Behalf Of Rick Maltese
> Sent: Sunday, November 17, 2013 11:02 PM
> To: radsafe at health.phys.iit.edu
> Subject: Re: [ RadSafe ] RadSafe Digest, Vol 1444, Issue 1
>
> Can anyone help me put together a paragraph that explains Becquerels 
> to the layman. I am creating a document to help explain radiation.
> Especially in relation to scary media about Fukushima. You can take a 
> look at what I've got so far.
>
>
> http://deregulatetheatom.com/reference/radiation/quick-radiation-refer
> en
> ce-guide/
>
>
> If there is also a graphic I would be very grateful.
>
>
> Rick Maltese
> 647-379-9655
>
> webcompose.ca  webdesign services
>
> leadsheetz.com  music services - transposing, composing, teaching etc
>
> rickmaltesemusic.com  piano gig page
>
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