Tuesday last week the local Montreal english-language daily newspaper carried a FRONT-PAGE Dirty Bomb story complete with fancy color graphics, titled "Is Montreal ready to handle a dirty-bomb attack ?" (you can see it at http://www.canada.com/montreal/montrealgazette/archives/story.asp?id=7E9C80F2-922A-4613-B40A-B6EA1635B294 -- make sure you click on the small picture to see the full graphics which appeared in the printed version).
I agree with Stewart & others that many people are using the "dirty bomb" threat to maximize public fear and even panic.
My reply to the newspaper story was as follows :
From: Franta, Jaroslav
Sent: Thursday June 13, 2002 10:03 AM
To: 'Editor of The Gazette'
Subject: RE: "Is Montreal ready to handle a dirty-bomb attack ?"
To the Editor,
While I was pleased to learn that DND is conducting training courses for emergency workers in Montreal ("Is Montreal ready to handle a dirty-bomb attack ?" 12 June 2002), I am amazed that such a story can make front-page news with fancy color graphics etc.
Although it is true that "many radioactive materials are stored in non-secure facilities," it is completely misleading to go on from there to imply that these common types of radiation sources can cause the kind of devastation claimed in the article.
Its like saying that "many explosive materials are stored in non-secure facilities," therefore terrorists can wipe out a couple of downtown blocks with a 100-tonne bomb.
If you don't believe me, think of the sodium azide in your car's air bag, definitely a "non-secure facility": Just because everyone has a gram of the stuff in their garage, that can hardly be interpreted to mean that its trivial to get 100 tons of it and blow up downtown Montreal.
This absurdity is only more true of radiation sources. We all have a few kilobecquerels of naturally-occurring radioactive potassium-40 and carbon-14 in our bodies (another "non-secure facility"). But that doesn't make it easy to obtain radioactive sources comprising many terabecquerels - that's billions of times more - the kind of quantity which might pose a radiological threat when dispersed over a not-too-large area. (Those particularly at risk in such an event would be people immobilized in that area by the initial explosion and emergency workers trying to dig survivors out of the rubble left by the explosion).
I suspect that somewhat more sophistication would be required than the knives and forks used by the 9-11 highjackers. Those of us working in the nuclear business know for a fact that when not shielded, radioactive sources are at their most hazardous when they are concentrated in one spot. Any dispersal or dilution weakens them just as it does any other poison or drug. Of course its easier to keep them safely shielded when they are contained in one spot rather than spread around.
In fact, multi-terabecquerel gamma radiation sources require large, heavy shielding containers - often weighing a tonne or more - which make handling, transport and weaponization (i.e. pulverization of the radioactive metal or ceramic) extremely difficult.
Handling it without the shielding would be lethal within hours, but simply attaching explosives to the side of the shielding vessel or even the source itself would do little more than launch it on a random trajectory. The result would be one or more dangerous "hot spots" somewhere in the vicinity, but no general area contamination in and around the city, as depicted in the Gazette graphics.
Moreover, such powerful radiation sources are - contrary to the quoted Greenpeace claims - fairly rare. They are typically part of large, fixed industrial or medical irradiation facilities. They are NOT the "every day shipment" radiopharmaceutical variety used in diagnostic and treatment procedures of every hospital's nuclear medicine department.
This latter, while hazardous when concentrated in their flask and unshielded, would likely not even require site decontamination if dispersed over a few blocks. After all, patients who receive such radiopharmaceuticals eventually urinate them into the same sewer system as everyone else. Rain would tend to have a similar cleansing effect on outdoor contamination. These radioactive materials are short-lived isotopes, which loose their radioactivity within days or less - that's why they need to be shipped around by suppliers all the time - in contrast to the large fixed gamma radiation sources, which typically last for years. Radiopharmaceuticals tend not to be strong gamma sources, but rather beta radiation sources, which are of little concern unless ingested or left unwashed on one's skin.
Nor is it as though we had no knowledge of what the consequences of radioactive contamination with large sources can be.
The 1987 radiation incident in Goiania, Brazil, is particularly relevant to this issue. In this case, some scavengers got hold of a large Cesium-137 source from a medical facility, an abandoned medical clinic. They carted the heavy shielded container home, and after a few days succeeded in opening it partially using various power tools. Later they spread small amounts of the Cesium-137 on their bodies and distributed it to their family and friends because it looked interesting (it glowed a pretty blue color in the dark). A total of about 250 people were exposed to it, but of those people, only four actually died from radiation exposure. Close to a quarter million people demanded the government test them to make sure that they weren't contaminated. Its public fear that is the worst enemy.
This was an extreme example, which subsequently led to increased regulation and security measures around the world. Details of it appeared in the January 1991 special issue of Health Physics journal, a 100-plus page (solid text) volume subtitled "The Goiania Radiation Accident."
As the specialist physicians of the Instituo de Radioprotecao e Dosimetria of Brazil explained, "participation of the doctors of the city of Goiania and the Hospital's medical staff itself... was greatly reduced due to fear or misinformation... instead of helping us by explaining exactly what was happening, and printing integral interviews with scientists working on the project... irresponsible yellow journalism stirred fear in the population ...hysteria instigated by the media was very expensive for the government and extremely painful to those involved... the victims of Cesium 137 were rejected by an entire city and its population... as much discriminated against by society (as are) AIDS patients."
How many times have reporters gotten burned trying to get technical information from bogus sources like Greenpeace ? Yet they keep doing it ! How about debunking this nonsense in another front-page article ? Not likely, huh ?
Regards,
Jaro
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I will let you know if & in what condition the article got printed....