BBC HomeExplore the BBC
This page has been archived and is no longer updated. Find out more about page archiving.

24 September 2014
Science & Nature: TV & Radio Follow-upScience & Nature
Science & Nature: TV and Radio Follow-up

BBC Homepage

In TV & Radio

Contact Us

You are here: BBC > Science & Nature > TV & Radio Follow-up > Horizon
First shown: BBC Two, Thursday 30 January 2003
Dirty Bomb

Dirty Bomb - transcript

NARRATOR (BERNARD HILL): In the last year the world has started to hear about a new kind of terrorist weapon, a weapon designed deliberately to spread fear and create a cancer time bomb. It might sound unreal, but experts say it's not.

DR JACK CARAVELLI (US Department of Energy): We simply don't have the luxury of saying to terrorists we're not prepared for this, so please wait until we're ready. We don't have that luxury.

NARRATOR: But could it really happen to us and how much damage would it do? What would happen if we were attacked by a dirty bomb? The dirty bomb threat first materialised when a very strange incident took place in Moscow. Crack teams from the city's police department descended on a park near the Kremlin. They had received a tip-off. Somewhere in the park there was a bomb.

COLONEL STANISLAV LEKAREV (Federal Security Service (retired)): The danger seemed to be serious. Nobody wanted this kind of problem right next to the Kremlin.

NARRATOR: The message also claimed that there was something different about this bomb, but it didn't say what. Then deep inside the park, buried beneath leaves, the police found a package.

STANISLAV LEKAREV: When they cut the tape around the package nobody knew whether they might cut some wiring connected to a detonator and blow themselves up.

NARRATOR: And then they discovered what made the bomb so different. It was packed with radio-active material.

STANISLAV LEKAREV: It was the first time the Russian Secret Service had dealt with situation like this. The whole incident was taken very seriously at the highest levels.

NARRATOR: The lethal package was removed to Secret Service laboratories, but if it had detonated radioactive material could have spread across central Moscow. This strange event should have been a warning to the world, but the Russian government hushed it up. Few in the West would realise that, for the first time ever, terrorists had shown they could build a dirty bomb. The dirty bomb is perhaps the least understood of all terrorist weapons. We have all heard of it, but few of us know what it would do. Wrongly it is sometimes called the poor man's nuclear weapon.

JACK CARAVELLI: A dirty bomb is not a nuclear weapon, but it is a real threat. It is a weapon that could reek havoc in ways far beyond its physical consequences and that makes it an ideal terrorist weapon.

NARRATOR: The aim of a real nuclear bomb is destruction. Just one can destroy an entire city. But a nuclear bomb is also difficult and expensive to build. It needs highly specialised equipment and weapons-grade radioactive material, like plutonium. Not even Al Qaeda can lay claim to these. But terrorists wouldn't need any of these to build a dirty bomb.

JACK CARAVELLI: In many ways it's low-tech and that is one of the most concerning things. The dirty bomb really is not a, a major technical challenge.

NARRATOR: That's because a dirty bomb is just ordinary explosives mixed with low grade radioactive material.

VINCENT CANNISTRARO (Former Chief of Counter Terrorism, CIA): It just requires the knowledge of making a conventional bomb. All you need to do to make it a dirty bomb is to add some kind of radioactive material.

NARRATOR: The dirty bomb is not then about creating a huge nuclear explosion. The blast could be tiny, perhaps killing no one at all. But the dirty bomb does share one chilling characteristic with its nuclear sibling: both produce a cloud of smoke infested with radioactive particles - fall-out - and these particles emit one of the most powerful forms of energy known to man: gamma-rays. They can penetrate the building blocks of the human body, the DNA in our cells and tear them apart. This is radiation sickness and it can kill.

PROF. STEVE JACKSON (Cambridge University): Radiation sickness has a number of features - hair loss, sickness, vomiting - and this is really because the cells in your body sustain very high levels of radiation and that is actually damaging the DNA and other components of the cell to such a degree that those cells are actually dying.

NARRATOR: But even small radiation doses can be dangerous. Bit by bit they cause mutations in your cells and those can lead to deadly long-term consequences, like cancer.

STEVE JACKSON: Radiation's a very strange thing because potentially a very small amount of radiation could lead to changes that, for example, could trigger cancer in the long-term. All you really need for a disease such as cancer is for one cell to go wrong.

NARRATOR: But for years all our intelligence efforts were focussed on stopping our enemies developing the dirty bomb's mighty nuclear sibling. The dirty bomb itself just seemed too small. The simple truth was that no one believed it was a threat to us in America or Britain. But as the war in Afghanistan drew to an end a worrying discovery was made. It was a cache of documents suggesting Al Qaeda were interested in a new kind of weapon.

VINCENT CANNISTRARO: One of these documents spells out in very great detail how to make a dirty bomb. The understanding was basically at a fairly advanced physics level. It was a pretty well thought out scenario on how to make the most deadly kind of dirty bomb imaginable.

NARRATOR: Yet even after this, some experts were still sceptical that Al Qaeda would embrace the dirty bomb. And then US Intelligence got some news. An American citizen called José Padilla was working with Al Qaeda and he appeared to be planning something.

VINCENT CANNISTRARO: José Padilla apparently went to Al Qaeda and said look, give me some money and I'll carry out an operation for you, including a dirty bomb. Al Qaeda said OK, fine. Then they gave him $10,000.

NARRATOR: But just as Padilla landed on American soil carrying Al Qaeda's $10,000 the FBI swooped.

JOHN ASHCROFT (US Attorney General): We have disrupted an unfolding terrorist plot to attack the United States by, by exploding a radioactive dirty bomb, dirty bomb, dirty bomb.

NARRATOR: Suddenly our governments woke up to a new reality. Massive intelligence efforts were directed at stopping rogue states from acquiring the nuclear bomb, but we were completely unprepared for a dirty bomb. Most important of all, we had done almost nothing to stop terrorists obtaining the dirty bomb's key ingredient: low-grade radioactive material. But deep in the heart of Europe there is a man who has been worrying about the dirty bomb for years. Dr Abel Gonzalez works for the International Atomic Energy Agency. He and his team monitor all types of radioactive material around the globe. It is a much harder job than tracking just weapons-grade material, like plutonium.

DR ABEL GONZALEZ (International Atomic Energy Agency): Following Hiroshima and Nagasaki there was a big effort in the world to keep nuclear materials like plutonium and uranium very, very well under control. This has not happened with radioactive material, with low-grade material. Was not felt that this was needed. Everybody knew that you could not do a nuclear weapon with that. For why? To have that control.

NARRATOR: And then in December 2001 the Agency received some troubling news. It would ultimately show just how real the dirty bomb threat could be.

ABEL GONZALEZ: I received a telephone call from the Head of my Emergency Unit saying to me look, something is going on in Georgia.

NARRATOR: Reports, from this remote corner of the former Soviet empire, said that two men were in hospital with terrible radiation burns. They had spent a night deep in the Georgian forest beside some small, warm metal canisters.

ABEL GONZALEZ: That was the first flush that we got that could be a serious problem of sources.

NARRATOR: Only a radioactive source of remarkable power could have caused such severe injuries so quickly, but the mystery was: no one could think what it might be.

ABEL GONZALEZ: I was convinced that my people either have drunk too much vodka, or that they have made a mistake for we were absolutely convinced that was impossible that the source of such an amount of activity would existed.

NARRATOR: The Agency's first priority was to recover the mysterious radioactive canisters. They were in a remote mountain range accessible only by dirt track. Within moments of arriving, it was clear what the recovery teams were dealing with. The two canisters contained a low-grade radioactive material called strontium. Radioactivity can be measured in units known as gigabequerels and these canisters registered a massive one million gigabequerels each. That meant that each contained the same amount of strontium as had been spewed out across Europe during the Chernobyl accident.

ABEL GONZALEZ: For me that was shocking 'cos I knew the amount of contamination that the Chernobyl accident has created.

NARRATOR: The radiation levels were so high that the rescue team could only operate in short bursts.

ABEL GONZALEZ: The radiation was so strong that our people who work near that source only for 40 seconds.

NARRATOR: One by one the strange canisters were carefully levered out from between rocks. Any longer than 40 seconds each and the team would have been risking exposure to the radiation. 25 men worked around the clock to recover the deadly canisters finally loading them into a lead-lined drum.

ABEL GONZALEZ: For me it was very nervous times until my people call me and said the source is secure.

NARRATOR: But back in Vienna Dr Gonzalez now faced urgent questions. How many other radioactive sources like the ones in Georgia could be out there? He scoured the scientific literature and eventually stumbled on an obscure Soviet manual from 1983. It contained plans for a kind of generator powered by huge amounts of radioactive strontium.

ABEL GONZALEZ: This was opening the Pandora Box. What is all this about, how many we have of these, from where we can get information?

NARRATOR: It became clear that thousands of these generators had been built. It meant the key ingredient for a dirty bomb was all over the former Soviet Union.

ABEL GONZALEZ: Was not that we have found one source and the problem was over. Many of these has been produced in the former Soviet Union.

NARRATOR: And there was more serious news to come. Agency inspectors turned up more strange devices. Mounted on trucks they were part of a vast and forgotten attempt to make Soviet farming more productive by blasting seeds with radiation. The strange machines contained a radioactive material: caesium chloride, and for anyone building a dirty bomb caesium chloride has one uniquely attractive feature.

ABEL GONZALEZ: Caesium chloride is really a talc powder, like a talc powder. Very, very, very dispersible.

NARRATOR: Powdery material could spread the contamination far and wide.

ABEL GONZALEZ: You know what happen in your home if you open a talc powder box. After a few hours you will have talc all over your home.

NARRATOR: It is now clear that for decades Russia had been conducting a secret love affair with radioactivity. Agency inspectors have established that the country is littered with forgotten caesium and worryingly, no one knows whether any of it has already fallen into the wrong hands. So how much damage could a bomb using Soviet material actually do? Horizon asked a specialist team of scientists to devise a credible dirty bomb scenario.

GRAHAM SMITH (Enviros Consulting): The factors that we have to consider are the type…

MICHAEL LEVI (Federation of American Scientists): …the technical threshold here is much lower… …type of challenge that we could be faced with…

GRAHAM SMITH: …or what the explosion probably…

NARRATOR: Horizon commissioned Enviros, a consultancy that advises nuclear authorities around the world, to model a fictional explosion. The results were then cross-checked by Michael Levi, the defence expert at the Federation of American Scientists.

MICHAEL LEVI: Typical wind speed is about 10km/h…

GRAHAM SMITH: …the obvious question is what's the weather like?

NARRATOR: In this fictional scenario the dirty bomb contains about 10lbs of an explosive, like Semtex, together with 74,000 gigabequerels of caesium chloride. That's the contents of just one Soviet seed irradiator, a pile of powder you could hold in your hands. In the model the target is Trafalgar Square. The terrorists themselves would not survive. Anyone handling the caesium for long enough to build a bomb would die within weeks from radiation sickness, but the one thing we do know about Al Qaeda is that they are not afraid of death.

VINCENT CANNISTRARO: When a group is willing to die handling this kind of material then there really aren't any limits on their ability to carry out a nightmare scenario.

NARRATOR: The blast could kill perhaps 10 people immediately. Then, within minutes, the emergency services would discover that this was no ordinary bomb. Because, as Horizon's model shows, the real purpose of the dirty bomb lies in what could follow next.

GRAHAM SMITH: The simple buoyancy of the air that's been heated by the explosion may carry the radioactive material perhaps tens of metres up into the air.

NARRATOR: Loaded with millions of tiny radioactive particles the heated air would very quickly begin to spread.

GRAHAM SMITH: If we're talking about wind speeds of metres per second, five metres per second perhaps, then to go 100m that's 20 seconds, to go a kilometre that's only a minute or so.

NARRATOR: In seconds, depending on the direction of the wind, the plume could reach Whitehall. A minute later Charing Cross. The City would be next. In just half an hour radioactive smoke could reach London suburbs 10km away.

GRAHAM SMITH: We've got contaminated air moving across a section of London and in general nobody would be aware that that contamination was there.

NARRATOR: Then as the plume cools the tiny radioactive particles would lose their buoyancy. They would fall onto people who would be completely unaware of the danger around them. The particles would drift into drains and settle on grass and trees in nearby parks. The good news is that the dirty bomb would result in few immediate problems. The levels of radioactivity are low enough to ensure that almost no one would suffer radiation sickness. Instead Londoners would face a different problem, a long-term one.

GRAHAM SMITH: The problem that would arise would be that in the longer term these people would have an increased risk of cancer due to that radiation exposure.

NARRATOR: And this is where the dirty bomb's threat really lies because radioactivity doesn't disappear. Left undisturbed, the particles could remain harmful for up to 200 years. Gradually the radiation would start to alter the cells in our bodies.

STEVE JACKSON: A very important thing to bear in mind about cancer is that it's a disease that evolves over time and in order for a cell in your body to become fully cancerous it's got to accumulate multiple mutations. Low levels of radiation over a considerable period of time can slowly, gradually cause those mutations to take place.

NARRATOR: Radiation doses are measured in units called millisieverts. Every year we receive about two millisieverts due to natural background radiation. The model shows that five kilometres from the blast doses would be just one millisievert above background. People who stayed there would face a tiny increased risk of dying of cancer, just one in 1,000, but one kilometre away radiation doses would go up to six times background. Anyone remaining there would face an increased cancer risk of about one in 100.

STEVE JACKSON: We're moving into territory that is very significant and I think it would be very difficult to justify individuals being exposed to that kind of additional risk on a day-to-day basis.

NARRATOR: Then the model measured risks half a kilometre away.

GRAHAM SMITH: Out to about 500m or so in the down-wind direction the risk to people dying of cancer as a result of this radiation exposure would be about one in 50. One person in 50 could be dying as a result of the weapon exploding.

NARRATOR: 200m from the blast radiation doses would reach 160 millisieverts a year.

STEVE JACKSON: We are really talking about very significant increases in radiation here. This is 80 times the normal background level of radiation.

NARRATOR: Doses this high could equate to a one in seven increased risk of dying of cancer.

GRAHAM SMITH: The people who continue to use the land there if there were no decontamination work would be at risk, an increased risk of dying of cancer of about one in seven.

NARRATOR: The exact threat would depend, of course, on the amount of radioactivity used. The Horizon model shows that a weapon built from just one Soviet seed irradiator could leave a cancer time-bomb hanging over London. There would be only one solution: a massive clean-up. No-one really knows what such a huge clean-up would involve, so scientists are turning to a nearly forgotten accident for clues. Dr Abel Gonzalez saw first-hand what happened. Fifteen years ago Brazilian scrap merchants stole a shiny canister and got more than they bargained for. It contained caesium chloride.

ABEL GONZALEZ: When they cut at the source and the powder got out then the contamination problems started.

NARRATOR: Radioactive powder drifted around the Brazilian city. Nearly 200 people were contaminated. Four would later die, including a little girl. Cleaning up the city turned out to be a mammoth task. Streets, pavements, shops and bars all needed to be decontaminated. Poisoned soil had to be dug up and carted away. Some homes were beyond salvation.

ABEL GONZALEZ: They were so contaminated that they have to, to demolish.

NARRATOR: The clean-up took six months and scientists worrying about the dirty bomb have noticed that it also created a completely unexpected problem.

MICHAEL LEVI: You don't get rid of radioactivity, you just transfer it to different material, so whatever it was transferred to, whether it would be water or some kind of a cloth, would have to be disposed of still in the way we dispose of radioactive waste.

NARRATOR: A handful of caesium had created a phenomenal 3,000 cubic metres of contaminated rubbish.

MICHAEL LEVI: The waste material produced by the clean-up was enough to cover a football field to waist height.

NARRATOR: And in the wake of a dirty bomb London would face the same problem, but on an even bigger scale.

MICHAEL LEVI: A dirty bomb incident using the same radioactive material would produce a much larger contaminated area and a much larger amount of waste simply because in the Goiânia case there wasn't even the intent to spread the material widely. In the dirty bomb that will be precisely the point.

NARRATOR: London's problems might not stop there. Some parts of the city may simply be too difficult to clean, others may be too expensive. It seems a dirty bomb built from just one Russian seed irradiator could lead to an almost unpalatable solution.

MICHAEL LEVI: In some cases either the cost of the technical barriers will be prohibitive to decontaminating an area and if people aren't willing to accept the radioactivity in that area the only feasible option will be to abandon that space.

NARRATOR: The effects could last a decade.

MICHAEL LEVI: It seems ridiculous to think that we might demolish, or abandon chunks of a city, but in some cases it may simply be that that will become our choice, that will become our preferred approach.

NARRATOR: A dirty bomb attack on this scale is plausible, but there is no real proof that terrorists have yet obtained radioactive material from Russia. In the meantime our government has woken up to the threat. Efforts are underway to make our borders more secure, but it is possible that this may not be enough because there is another way that would-be dirty bombers could get hold of the critical ingredients and it is a way that is much, much closer to home.

BRINT WHITMYER: 8.12., I'm Brint Whitmyer and you're listening to the Murphy in the Morning Show on 1075 KCL. Cold weekend. This is about as warm as it's going to get right now for the entire…

NARRATOR: In March 1998 the people of Greensboro, North Carolina woke up to what they thought was a perfectly normal spring day.

BRINT WHITMYER: …right now 43 Greensboro, 43 Winston-Salem, 44 at High Point…

NARRATOR: Chief Executive Tim Rice set off for work at the town's general hospital with a routine day ahead of him. He had no idea it would turn out to be the most extraordinary day of his life. That morning Rice would get a call from one of his doctors with urgent news.

TIM RICE (Moses Cone Hospital): I could hear in his voice he was very concerned and very disturbed and that was my first inkling that I've got a problem here.

NARRATOR: 19 tiny medical instruments had simply vanished from the hospital. Used for treating cancer, they were known as brachy therapy needles and they contained caesium.

TIM RICE: I had to kind of stop and scratch my head at first and ask the question: Joe, what is the caesium, what do we use it for? and he started to remind me we did keep about 15/17 doses of caesium, a radioactive substance, that we used for cervical cancer.

NARRATOR: Rice tried to keep up the illusion of normality as he ordered a top to bottom search of the 500-bed hospital.

TIM RICE: We were trying not to frighten people, but we were walking around the facilities with Geiger-counters. We were going room by room through the basements, through the crawl spaces, just everywhere we could think of that it could be.

NARRATOR: It became increasingly clear that the needles had not just been misplaced.

TIM RICE: The more I asked the less sense anything made. It was just gone. It became obvious we had to get other people involved who had more expertise.

NARRATOR: So they turned to Marion Eaddy, Chief Investigator for the state's Radiation Protection Division.

MARION EADDY (North Carolina Division of Radiation Protection): We immediately recognised the significance of 19 caesium sources that were unaccounted for.

TIM RICE: I asked about anybody stealing it for any reason, could you make a bomb with it, could you, what could you use it for, has it got street value?

MARION EADDY: We tried to think of scenarios where this radioactive material could have gone. If someone did take it on purpose where would it be?

NARRATOR: Armed with sensitive monitoring equipment Eaddy's team launched a city-wide search.

MARION EADDY: The fact that they could be essentially anywhere did make the search extremely difficult on us because of the sheer size of Greensboro.

NARRATOR: Helicopters were drafted in to join more than 60 officers combing the area.

MARION EADDY: We had the aerial monitoring flying low checking out the remainder of the city, we had everything but boats.

NARRATOR: But the radioactive caesium was never recovered. Someone out there, for some reason, still has it. The worrying truth is you don't even have to steal radioactive material in America. Some of it is just lying around. In February 2002 a North Carolina scrap yard took delivery of a twisted bundle of metal junk and found a nasty surprise inside.

MARION EADDY: It's the same source as was involved in the Moses Cone incident, the caesium again.

NARRATOR: This time the caesium was inside an industrial gauge. The gauge was used in factories for measuring levels and contained three times as much caesium as the Moses Cone needles, but it had been simply been thrown away. Thousands of radioactive devices have gone missing, from US hospitals, factories and building sites. No smaller than the sources from the former Soviet Union, many may still be suitable for building a dirty bomb.

JACK CARAVELLI: It's not just Russians, put it that way. We, we certainly have responsibilities and problems in our backyard. Do I worry about the possibility that a dirty bomb could be fabricated from US material, US sources, US sources of origin, the simple answer is yes I do worry about that.

NARRATOR: So Horizon decided to find out what could happen if a dirty bomb were built using a small American source.

MICHAEL LEVI: The main way that people are exposed to radiation from caesium…

GRAHAM SMITH: …there is in terms of measured radioactivity.

NARRATOR: In this fictional scenario the terrorists simply mix the caesium from an industrial gauge with the contents of a store-bought firework. The gauge contains 1,000 times less caesium that was used in London. In this scenario the target is Washington's Metro, used by half a million commuters every day. There is a small flash as the mixture beside the track ignites. Almost immediately a highly effective dispersal mechanism is at work: the trains. They push radioactive particles down the track towards commuters.

MICHAEL LEVI: There won't be any immediate signs that the dispersal of radioactive materials has occurred. We can't see or hear or taste them.

NARRATOR: But the caesium particles would quietly begin to spread. Radioactive dust would enter carriages as the doors opened.

MICHAEL LEVI: People could track/trap them on their feet, underneath their shoes. Trains could move them actively between stations.

NARRATOR: While some particles would be carried on to the next stop, others would move via the Metro's ventilation system and no one in Washington would know until 24 hours later when the terrorists announce they've attacked the Metro.

VOICE: Terror alert. America under attack. Washington on alert.

NARRATOR: In this scenario Horizon's model shows that the risks would turn out to be very low. Commuters travelling for 50 minutes would receive just twice the dose they get each year from background radiation. That's a tiny increase in their cancer risk - just one in 4,000.

MICHAEL LEVI: Individual riders are unlikely to be affected even if the material remains there for several hours without being disclosed simply because any one person doesn't spend all that much time in the station.

NARRATOR: The only people in danger would be staff. After a day's work their fatal cancer risk could rise by one in 100.

STEVE JACKSON: They would have to be carefully monitored and I'm sure they'd actually want to be monitored for a considerable period afterwards.

NARRATOR: So the direct health risks of such an attack really are low, but there is another way that a small dirty bomb could cause havoc: panic.

VOICE MONTAGE: The authorities said they were urgently trying to establish the scope of radio… …scale of radioactive contamination… …who travel into the city by Metro… …the threat of a further dirty bomb attack… …stay put, don't panic message…

NARRATOR: When news of the attack breaks people would be desperate to know the extent of the contamination.

JACK CARAVELLI: The news media comes on and says a small device has exploded in Washington, what is the reaction of the populace, how do you control that, what do you say to them? Do you say a lot, do you say very little?

VOICE: Officials stress the need for calm…

NARRATOR: The problem is it could be hard to provide answers as fast as people want them. Contamination could be patchy, high in some places, low in others, making it difficult to be sure for a day or two how serious the attack had been.

JACK CARAVELLI: It may be unclear for perhaps some period of time exactly what the radioactivity was, how much there was of it.

NARRATOR: And that short period of uncertainty could be enough to fuel our fears.

JACK CARAVELLI: The objectives are to terrorise. I don't know that many people would make the distinctions between a small radioactive source and the larger radioactive source. Those distinctions may be totally lost on the population, so for that reason even the smallest of radioactive source if they're used in a dirty bomb scenario could be very disruptive.

NARRATOR: Once again the best road map we have for people's likely reaction is what happened in Brazil. In the wake of the caesium accident crowds of fearful residents took to the streets.

ABEL GONZALEZ: It became a soup of, of panic.

NARRATOR: In fact the numbers affected turned out to be far less than originally feared. In a city of a million residents barely 200 were contaminated, but nobody knew that to start with. More than 100,000 people, 10% of the city's population, queued for radiation screening.

ABEL GONZALEZ: Everybody want to be monitored, even if you say to them don't worry, you were very far away, there is no chance that… No, no, I want to be monitored.

NARRATOR: Hospitals and clinics were swamped.

ABEL GONZALEZ: People want the absolute reassurance that they are out of the problem.

NARRATOR: Now experts are trying to draw lessons from Brazil to help us prepare for the aftermath of even a small dirty bomb.

MICHAEL LEVI: Take as an example the accidental dispersal of caesium in Goiânia, Brazil where 10% of the city's population demanded screening for exposure to radiation. Those kinds of things are likely to overwhelm our public health system and if 10% of Washington shows up at the hospital you've got some things to confront.

NARRATOR: First step towards reassuring a frightened American public would be a thorough decontamination of the Metro. That could be disruptive and expensive.

MICHAEL LEVI: We would shut down the subway in order to carry out the clean-up and that would result in massive inconveniences and economic losses.

NARRATOR: This then is possibly the biggest threat from the dirty bomb. A device using the material thrown away in North Caroline need not be lethal. It would not cause cancer. It is not a weapon of mass destruction, but it could frighten us and cost us money and that makes it a true tool of terrorism.

MICHAEL LEVI: Radiological terrorism can leverage public fear of radiation to take what would normally be considered a very small amount of radioactive material, something not all that dangerous, and turn it into a weapon that can have massive psychological and economic impact.

NARRATOR: Understanding this should help us to cope with any dirty bomb attack. In the meantime, efforts continue to try and make sure we don't ever have to find out.

JACK CARAVELLI: We know that the interest on the part of terrorists exists, that it's real, we know that the sources are out there, we know that many of them are not secured properly and that combination leads us to work feverishly to attack this problem.

Back to top of page

Science Homepage | Nature Homepage
Wildlife Finder | Prehistoric Life | Human Body & Mind | Space
Go to top

About the BBC | Help | Terms of Use | Privacy & Cookies Policy