In January this year, a nuclear trafficking case made the international news headlines. The United States Department of Justice announced that Takeshi Ebisawa, an alleged Japanese gangster, had pleaded guilty to charges of major narcotics trafficking as well as conspiring to traffic nuclear materials. The indictment states that Ebisawa believed he was offering the materials—including uranium and plutonium—to representatives of the Iranian government, but they were in fact US agents. He claimed to be selling the nuclear material on behalf of a Myanmar rebel group in return for guns.
The Ebisawa case and how it has been covered highlight important questions about how the issue of nuclear materials trafficking is reported in the media, and how serious a security threat it really poses today. To separate the facts from the myths, SIPRI talked to nuclear expert Robert E. Kelley, a veteran of the US nuclear weapons complex, nuclear analyst and SIPRI Distinguished Associate Fellow.
Interview by Caspar Trimmer, Senior Communications Officer, with additional input from Vitaly Fedchenko, Senior Researcher in the SIPRI Weapons of Mass Destruction Programme.
Q. How big a problem is nuclear materials trafficking today?
RK: Overall, I’d say that trafficking in nuclear materials [see the box] is something we need to be worried about, because it's illegal and because it suggests that there are holes in the regulatory, accounting and border control systems of several states. However, the cases we do see tend to be small and overhyped and generally involve natural, depleted or only slightly enriched uranium, not weapons-grade material.
I know of no cases so far where trafficked nuclear materials have come close to the minimum amount needed to make a nuclear explosive. In most of the reported cases the materials being offered for sale posed little or no risk of nuclear proliferation. And often, like in the Ebisawa case, they are sting operations, where the supposed buyer has been an intelligence or law enforcement agency. In fact, government sting operations have created a market in some cases.
Ebisawa’s main business was trafficking large quantities of narcotics and gunrunning. From reading the indictment, my impression is that the uranium offer seems to have been an afterthought. In addition, anyone with the millions of dollars that potential traffickers ask for should also be smart enough to know they have zero chance of building a bomb out of low-enriched uranium fuel pellets or raw ore.
Q. Media stories about nuclear materials trafficking tend to treat all materials as if they were a major security threat, which can be misleading. As you say, most of the reported attempted trafficking cases involve natural uranium or nuclear source materials. Could these pose a serious proliferation risk if they were trafficked?
RK: Practically speaking, the answer is no. Uranium ore is found in the ground in many parts of the world and has low radioactivity levels. It's not regulated by any security or IAEA [International Atomic Energy Agency] safeguards accounting procedures until it has been concentrated and refined a good deal. So the amount of uranium ore that someone could steal is virtually unlimited, but it still would not be a serious proliferation risk.
‘Yellowcake’, or uranium ore concentrate, has appeared in some headline-grabbing cases, including the Ebisawa case. But again, you would need tons of it and a very sophisticated industrial process to convert and enrich it enough to make weapons-grade material. Even for a state, it would take months of work and millions of dollars. Only a handful of states currently have the necessary enrichment facilities.
The IAEA recognizes yellowcake as a nuclear source material, but IAEA safeguards agreements impose only very limited accounting requirements on it. However, because yellowcake is relatively valuable, the people who produce and ship it tend to keep careful track of it for financial and safety reasons.
Thorium is also mentioned in the Ebisawa case. Thorium is used very widely in industry and household applications—for example in sandpaper, welding rods, the mantles of gas lamps. The IAEA considers it a nuclear source material because it can be turned into uranium-233 (U-233), which could be used in a bomb. But it is extremely hard and expensive to do, and U-233 is very difficult to handle safely. Only a handful of countries have ever bothered trying to produce U-233 in this way.
The other nuclear source material recognized by the IAEA is depleted uranium. This is a by-product of enrichment that has lower concentrations of fissile isotopes than natural uranium. The IAEA imposes some accounting requirements on depleted uranium because it can be put into a reactor to create plutonium. But it’s not a problem in practice. Even if someone stole 20 tonnes of depleted uranium—which the IAEA defines as a significant quantity of that material—you still have an accounting problem but not a serious proliferation risk.
Q. How much do the proliferation risks change when you get to trafficking of special fissile materials?
RK: Further along the fuel cycle you have the special fissile materials, chiefly enriched uranium and plutonium.
Low-enriched uranium(LEU) is a mildly radioactive compound most commonly used in nuclear fuel. Because of the global market, a lot of LEU moves between countries. Most nuclear fuel shipments are subject to IAEA safeguards. However, even if there were diversion, the proliferation risk would be minimal. It is just not going to be useful as a nuclear explosive without significant further processing and enrichment that is beyond the resources of all but a few states.
When you get to 20 per cent enrichment [i.e. where the isotope U-235 comprises 20 per cent of the total mass of the material] you have highly enriched uranium (HEU). This threshold is often used to shape non-proliferation policy, but here definitions are unfortunate. You really need something closer to 70 per cent enrichment to make a useful nuclear explosive. In fact, 80 per cent is normally considered the threshold of interest.
Plutonium only exists in nature in tiny quantities and any significant amount has to be made in a nuclear reactor. Some forms of plutonium can be used to make nuclear warheads. However, the facilities needed to produce plutonium—nuclear reactors and plutonium separation plants—are hard to conceal from detection using satellite imagery, environmental sampling and other methods. Plutonium is also highly toxic and difficult to handle.
You can find small amounts of plutonium in most of the nuclear industry, because it’s a by-product of uranium fuel reprocessing. It may be found occasionally in tiny amounts on the outside of shipping containers used in the industry as well as in environmental samples—but that does not mean there has been any trafficking. In fact, if you look hard enough you could detect stray microparticles of ‘weapons-grade’ plutonium pretty much anywhere. Small amounts of it remain in the environment as fallout from nuclear testing done by various states decades ago.
As for the trafficking risks, acquiring enough plutonium or HEU on the black market to make a nuclear explosive is challenging because they are extremely valuable strategic materials, and governments and people who own them really go out of their way to make sure no-one can steal them. However, if kilograms of HEU or plutonium did go missing, it would be very, very serious.
Q. Are there other ways that nuclear materials could be weaponized, short of creating a nuclear explosive device?
RK: One term that is often associated with nuclear materials trafficking, especially when it comes to terrorism, is ‘dirty bombs’—or more accurately, radioactive dispersal devices or RDDs. The theory behind dirty bombs is that dangerous material is scattered about using conventional explosives. There is no nuclear reaction, just dispersal of a poisonous or hazardous substance.
I don’t believe a dirty bomb has ever been used in the real world, but they are theoretically possible. When it comes to nuclear materials, plutonium isotopes are a threat when inhaled and so in powder form they could be dispersed using an RDD to cause harm.
This is the one very disturbing item in the Ebisawa case: the reported detection of ‘weapons-grade’ plutonium in the samples he provided. It seems unlikely that he would have access to the kilograms needed to produce a nuclear explosive, but just a few grams could be a public health risk, including in an RDD. The completely unscientific language used in the DoJ indictment makes it impossible to know whether the samples contained significant quantities of plutonium or just microparticles from atmospheric pollution. That is overwhelmingly the most important element of the case to follow up.
On the other hand, if a dirty bomb were made using uranium or thorium it would not pose much of a danger, because once the material was widely dispersed its concentration, and therefore the danger, would be greatly reduced. It would be more of a clean-up nuisance—a weapon of mass disruption rather than mass destruction. But because of the public’s fear about radioactive substances a dirty bomb could still have a disproportionate psychological impact.
Q. What systems are in place to identify potential cases of nuclear materials trafficking?
RK: If we discount intelligence and sting operations, as in the Ebisawa case, there are a couple of ways that this is done. First, of course, there are accounting and verification systems, including nuclear safeguards. The accounting system might begin to detect that materials are missing, or that materials are there, or being produced, that shouldn’t be. These are separate from nuclear security arrangements. Nuclear security is the responsibility of states and takes the form, colloquially speaking, of ‘guns, guards and fences’.
Another way is radiation detection at transportation choke points. Airports are a good example. There’s a lot of investment in detecting radiation sources—especially nuclear materials. The USA has spent a huge amount of money on radiation detection sensors in major container ports in Europe, China and Singapore because it is worried about nuclear weapons or nuclear materials being transported into the USA in a container.
Q. Could nuclear materials trafficking become a more serious problem in the future?
RK: While trafficking of yellowcake and even HEU at lower levels of enrichment does not pose a serious future threat, there are certainly risks when it comes to weapons-grade nuclear materials.
For example, there have been concerning developments in North Korea. North Korea is already thought to have accumulated enough HEU to build up to 90 weapons. This is a very large stockpile for a small country and it wants even more. Kim Jong Un has instructed the country’s centrifuge enrichment facilities to accelerate production. There is a genuine risk that he is trying to develop an international nuclear proliferation network like that of [Pakistani metallurgist] AQ Khan, which passed nuclear secrets to Iran, Libya and North Korea. If North Korea directly exports weapons-grade HEU, a new nuclear-armed actor may emerge without warning. As I said, trafficking in weapons-grade material—very highly enriched uranium or plutonium—would create very serious risks.
Also, it is not just states that will be of proliferation concern in the coming decades. Individuals with unparalleled power are appearing in several regions of the world. We have never been in this position before, where one of these individuals could develop their own nuclear programme or manipulate a state programme.
I worked in US government nuclear weapons labs in the 1980s. At that time we laughed at films where arch-villains developed secret nuclear weapons programmes. But today we see private actors with financial resources that are comparable to a government. They are also leading in areas that used to be the exclusive domain of government, like enrichment, and designing and launching rockets. In nuclear weapon states like the USA, the IAEA does not apply safeguards in the same way as it would for non-nuclear weapon states. It is not too far-fetched to imagine a new set of proliferation risks stemming from this combination of factors.
And then there is another set of risks related to the growth of civilian nuclear power generation. In this case it is not the uranium fuel itself, but rather that there will be much greater quantities of plutonium available. All reactors using uranium fuel produce some plutonium, especially breeder reactors, which are currently being built by China, India and Russia. As the feedstock keeps going around the cycle, the plutonium content increases and gets purer. This increases the risk that some will be diverted.
If you look at the new Rokkasho fuel-reprocessing plant being built in Japan, the uncertainty in their measurement systems means they might not catch significant quantities of low-quality plutonium that could be a target for traffickers. In the coming years there are going to be tonnes, or even hundreds of tonnes, of plutonium moving around the world. Because plutonium needs very little processing and no further enrichment in order to be used in a weapon, it would be an attractive material for a proliferator. But this is not a new discovery. Because plutonium is clearly an extremely valuable and dangerous material, it is tightly controlled both for proliferation risk and toxicity reasons.
Q. Any closing thoughts?
RK: Press reports often confuse the risk from different forms of trafficking in radioactive materials. When there are occasional cases involving trafficking of uranium ore, yellowcake, LEU fuel pellets, thorium-based materials and so on, these are of no consequence for public safety, only a sign that controls on valuable industrial materials are inadequate. And a number of nuclear materials trafficking cases are stings, where national authorities posing as buyers have elicited offers to sell. In many cases, exorbitant sums of money are demanded for materials that are virtually worthless. Any potential buyer with that much money would undoubtedly know this.
In contrast to cases like that, trafficking in very highly enriched uranium or plutonium isotopes would be a serious cause for concern. There is only one aspect of the reported trafficking in nuclear materials in the Ebisawa case that is important from a proliferation or public safety risk standpoint. That is the casual reference to ‘weapons-grade plutonium’, which leaves more questions than answers.
In January this year, a nuclear trafficking case made the international news headlines. The United States Department of Justice announced that Takeshi Ebisawa, an alleged Japanese gangster, had pleaded guilty to charges of major narcotics trafficking as well as conspiring to traffic nuclear materials. The indictment states that Ebisawa believed he was offering the materials—including uranium and plutonium—to representatives of the Iranian government, but they were in fact US agents. He claimed to be selling the nuclear material on behalf of a Myanmar rebel group in return for guns.
The Ebisawa case and how it has been covered highlight important questions about how the issue of nuclear materials trafficking is reported in the media, and how serious a security threat it really poses today. To separate the facts from the myths, SIPRI talked to nuclear expert Robert E. Kelley, a veteran of the US nuclear weapons complex, nuclear analyst and SIPRI Distinguished Associate Fellow.
Interview by Caspar Trimmer, Senior Communications Officer, with additional input from Vitaly Fedchenko, Senior Researcher in the SIPRI Weapons of Mass Destruction Programme.
Q. How big a problem is nuclear materials trafficking today?
RK: Overall, I’d say that trafficking in nuclear materials [see the box] is something we need to be worried about, because it's illegal and because it suggests that there are holes in the regulatory, accounting and border control systems of several states. However, the cases we do see tend to be small and overhyped and generally involve natural, depleted or only slightly enriched uranium, not weapons-grade material.
I know of no cases so far where trafficked nuclear materials have come close to the minimum amount needed to make a nuclear explosive. In most of the reported cases the materials being offered for sale posed little or no risk of nuclear proliferation. And often, like in the Ebisawa case, they are sting operations, where the supposed buyer has been an intelligence or law enforcement agency. In fact, government sting operations have created a market in some cases.
Ebisawa’s main business was trafficking large quantities of narcotics and gunrunning. From reading the indictment, my impression is that the uranium offer seems to have been an afterthought. In addition, anyone with the millions of dollars that potential traffickers ask for should also be smart enough to know they have zero chance of building a bomb out of low-enriched uranium fuel pellets or raw ore.
Q. Media stories about nuclear materials trafficking tend to treat all materials as if they were a major security threat, which can be misleading. As you say, most of the reported attempted trafficking cases involve natural uranium or nuclear source materials. Could these pose a serious proliferation risk if they were trafficked?
RK: Practically speaking, the answer is no. Uranium ore is found in the ground in many parts of the world and has low radioactivity levels. It's not regulated by any security or IAEA [International Atomic Energy Agency] safeguards accounting procedures until it has been concentrated and refined a good deal. So the amount of uranium ore that someone could steal is virtually unlimited, but it still would not be a serious proliferation risk.
‘Yellowcake’, or uranium ore concentrate, has appeared in some headline-grabbing cases, including the Ebisawa case. But again, you would need tons of it and a very sophisticated industrial process to convert and enrich it enough to make weapons-grade material. Even for a state, it would take months of work and millions of dollars. Only a handful of states currently have the necessary enrichment facilities.
The IAEA recognizes yellowcake as a nuclear source material, but IAEA safeguards agreements impose only very limited accounting requirements on it. However, because yellowcake is relatively valuable, the people who produce and ship it tend to keep careful track of it for financial and safety reasons.
Thorium is also mentioned in the Ebisawa case. Thorium is used very widely in industry and household applications—for example in sandpaper, welding rods, the mantles of gas lamps. The IAEA considers it a nuclear source material because it can be turned into uranium-233 (U-233), which could be used in a bomb. But it is extremely hard and expensive to do, and U-233 is very difficult to handle safely. Only a handful of countries have ever bothered trying to produce U-233 in this way.
The other nuclear source material recognized by the IAEA is depleted uranium. This is a by-product of enrichment that has lower concentrations of fissile isotopes than natural uranium. The IAEA imposes some accounting requirements on depleted uranium because it can be put into a reactor to create plutonium. But it’s not a problem in practice. Even if someone stole 20 tonnes of depleted uranium—which the IAEA defines as a significant quantity of that material—you still have an accounting problem but not a serious proliferation risk.
Q. How much do the proliferation risks change when you get to trafficking of special fissile materials?
RK: Further along the fuel cycle you have the special fissile materials, chiefly enriched uranium and plutonium.
Low-enriched uranium (LEU) is a mildly radioactive compound most commonly used in nuclear fuel. Because of the global market, a lot of LEU moves between countries. Most nuclear fuel shipments are subject to IAEA safeguards. However, even if there were diversion, the proliferation risk would be minimal. It is just not going to be useful as a nuclear explosive without significant further processing and enrichment that is beyond the resources of all but a few states.
When you get to 20 per cent enrichment [i.e. where the isotope U-235 comprises 20 per cent of the total mass of the material] you have highly enriched uranium (HEU). This threshold is often used to shape non-proliferation policy, but here definitions are unfortunate. You really need something closer to 70 per cent enrichment to make a useful nuclear explosive. In fact, 80 per cent is normally considered the threshold of interest.
Plutonium only exists in nature in tiny quantities and any significant amount has to be made in a nuclear reactor. Some forms of plutonium can be used to make nuclear warheads. However, the facilities needed to produce plutonium—nuclear reactors and plutonium separation plants—are hard to conceal from detection using satellite imagery, environmental sampling and other methods. Plutonium is also highly toxic and difficult to handle.
You can find small amounts of plutonium in most of the nuclear industry, because it’s a by-product of uranium fuel reprocessing. It may be found occasionally in tiny amounts on the outside of shipping containers used in the industry as well as in environmental samples—but that does not mean there has been any trafficking. In fact, if you look hard enough you could detect stray microparticles of ‘weapons-grade’ plutonium pretty much anywhere. Small amounts of it remain in the environment as fallout from nuclear testing done by various states decades ago.
As for the trafficking risks, acquiring enough plutonium or HEU on the black market to make a nuclear explosive is challenging because they are extremely valuable strategic materials, and governments and people who own them really go out of their way to make sure no-one can steal them. However, if kilograms of HEU or plutonium did go missing, it would be very, very serious.
Q. Are there other ways that nuclear materials could be weaponized, short of creating a nuclear explosive device?
RK: One term that is often associated with nuclear materials trafficking, especially when it comes to terrorism, is ‘dirty bombs’—or more accurately, radioactive dispersal devices or RDDs. The theory behind dirty bombs is that dangerous material is scattered about using conventional explosives. There is no nuclear reaction, just dispersal of a poisonous or hazardous substance.
I don’t believe a dirty bomb has ever been used in the real world, but they are theoretically possible. When it comes to nuclear materials, plutonium isotopes are a threat when inhaled and so in powder form they could be dispersed using an RDD to cause harm.
This is the one very disturbing item in the Ebisawa case: the reported detection of ‘weapons-grade’ plutonium in the samples he provided. It seems unlikely that he would have access to the kilograms needed to produce a nuclear explosive, but just a few grams could be a public health risk, including in an RDD. The completely unscientific language used in the DoJ indictment makes it impossible to know whether the samples contained significant quantities of plutonium or just microparticles from atmospheric pollution. That is overwhelmingly the most important element of the case to follow up.
On the other hand, if a dirty bomb were made using uranium or thorium it would not pose much of a danger, because once the material was widely dispersed its concentration, and therefore the danger, would be greatly reduced. It would be more of a clean-up nuisance—a weapon of mass disruption rather than mass destruction. But because of the public’s fear about radioactive substances a dirty bomb could still have a disproportionate psychological impact.
Q. What systems are in place to identify potential cases of nuclear materials trafficking?
RK: If we discount intelligence and sting operations, as in the Ebisawa case, there are a couple of ways that this is done. First, of course, there are accounting and verification systems, including nuclear safeguards. The accounting system might begin to detect that materials are missing, or that materials are there, or being produced, that shouldn’t be. These are separate from nuclear security arrangements. Nuclear security is the responsibility of states and takes the form, colloquially speaking, of ‘guns, guards and fences’.
Another way is radiation detection at transportation choke points. Airports are a good example. There’s a lot of investment in detecting radiation sources—especially nuclear materials. The USA has spent a huge amount of money on radiation detection sensors in major container ports in Europe, China and Singapore because it is worried about nuclear weapons or nuclear materials being transported into the USA in a container.
Q. Could nuclear materials trafficking become a more serious problem in the future?
RK: While trafficking of yellowcake and even HEU at lower levels of enrichment does not pose a serious future threat, there are certainly risks when it comes to weapons-grade nuclear materials.
For example, there have been concerning developments in North Korea. North Korea is already thought to have accumulated enough HEU to build up to 90 weapons. This is a very large stockpile for a small country and it wants even more. Kim Jong Un has instructed the country’s centrifuge enrichment facilities to accelerate production. There is a genuine risk that he is trying to develop an international nuclear proliferation network like that of [Pakistani metallurgist] AQ Khan, which passed nuclear secrets to Iran, Libya and North Korea. If North Korea directly exports weapons-grade HEU, a new nuclear-armed actor may emerge without warning. As I said, trafficking in weapons-grade material—very highly enriched uranium or plutonium—would create very serious risks.
Also, it is not just states that will be of proliferation concern in the coming decades. Individuals with unparalleled power are appearing in several regions of the world. We have never been in this position before, where one of these individuals could develop their own nuclear programme or manipulate a state programme.
I worked in US government nuclear weapons labs in the 1980s. At that time we laughed at films where arch-villains developed secret nuclear weapons programmes. But today we see private actors with financial resources that are comparable to a government. They are also leading in areas that used to be the exclusive domain of government, like enrichment, and designing and launching rockets. In nuclear weapon states like the USA, the IAEA does not apply safeguards in the same way as it would for non-nuclear weapon states. It is not too far-fetched to imagine a new set of proliferation risks stemming from this combination of factors.
And then there is another set of risks related to the growth of civilian nuclear power generation. In this case it is not the uranium fuel itself, but rather that there will be much greater quantities of plutonium available. All reactors using uranium fuel produce some plutonium, especially breeder reactors, which are currently being built by China, India and Russia. As the feedstock keeps going around the cycle, the plutonium content increases and gets purer. This increases the risk that some will be diverted.
If you look at the new Rokkasho fuel-reprocessing plant being built in Japan, the uncertainty in their measurement systems means they might not catch significant quantities of low-quality plutonium that could be a target for traffickers. In the coming years there are going to be tonnes, or even hundreds of tonnes, of plutonium moving around the world. Because plutonium needs very little processing and no further enrichment in order to be used in a weapon, it would be an attractive material for a proliferator. But this is not a new discovery. Because plutonium is clearly an extremely valuable and dangerous material, it is tightly controlled both for proliferation risk and toxicity reasons.
Q. Any closing thoughts?
RK: Press reports often confuse the risk from different forms of trafficking in radioactive materials. When there are occasional cases involving trafficking of uranium ore, yellowcake, LEU fuel pellets, thorium-based materials and so on, these are of no consequence for public safety, only a sign that controls on valuable industrial materials are inadequate. And a number of nuclear materials trafficking cases are stings, where national authorities posing as buyers have elicited offers to sell. In many cases, exorbitant sums of money are demanded for materials that are virtually worthless. Any potential buyer with that much money would undoubtedly know this.
In contrast to cases like that, trafficking in very highly enriched uranium or plutonium isotopes would be a serious cause for concern. There is only one aspect of the reported trafficking in nuclear materials in the Ebisawa case that is important from a proliferation or public safety risk standpoint. That is the casual reference to ‘weapons-grade plutonium’, which leaves more questions than answers.
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