Nuclear Weapons: The Final Pandemic Preventing Proliferation and Achieving Abolition Dangers Associated with Use of Highly Enriched Uranium in Medical Isotope Production Martin B. Kalinowski Director, Carl Friedrich von Weizsäcker Center for Science and Peace Research (ZNF), Germany

Nuclear Weapons: The Final Pandemic – Preventing Proliferation and Achieving Abolition Session: HEU and Medical Research Reactors: A Hidden Source of Nuclear Terrorism The dangers associated with the use of highly enriched uranium in medical isotope production London, 3-4 October 2007 Martin B. Kalinowski, Britta Riechmann, Matthias Tuma Carl Friedrich von Weizsäcker-Centre for Science and Peace Research University Hamburg

The dangers associated with the use of highly enriched uranium in medical isotope production Abstract: The use of highly enriched uranium (HEU) for medical isotope production is of concern for nuclear weapons proliferation, because it is a direct use material for nuclear weapons. The Reduced Enrichment for Research and Test Reactors (RERTR) program was initiated in 1978 with the goal to minimize the HEU accessibility. The goal is to convert all reactors to low enriched uranium (LEU), i.e. down below 20% enrichment in uranium-235. Even 30 years later, this program had only limited success in the area of isotope production for medical applications. While the global demand of HEU for research reactors is declining from more than 2,000 kg per year in to projected 500 kg/y in a few years, the use of HEU for medical isotope production is increasing and likely hitting an annual consumption level of 100 kg soon. This is four times the significant quantity of 25 kg of HEU assumed to be sufficient for the construction of one nuclear bomb. Not only the driver fuel of isotope production reactors often uses HEU; it is typically used as target material as well at 90% enrichment and higher. The latter is of even higher proliferation concern since only about 2% of the HEU is consumed. Most radioactivity is removed by chemical separation and as a result the radiation barrier is low. The isotope production from uranium irradiation adversely affects the verification of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). The chemical separation releases radioactive xenon that is used as atmospheric indicator for nuclear explosions. First experiences with the international monitoring system show that most detections are caused by a few facilities known to produce medical isotopes. A global radioxenon emission inventory shows that these are by far the strongest sources. A single extraction plant can release in the order of 10E15 Bq of xenon-133 per year. This is as much as all nuclear reactors of the world taken together are emitting in the same time. In addition, due to the short irradiation time, the isotopic activity ratios of isotope production may be difficult to distinguish from the signature that is characteristic for nuclear explosions. In order to study the HEU and xenon issues, detailed information would be required. Unfortunately, the companies and national authorities are very cautious in providing any data, in order to protect proprietary interests in light of a highly competitive isotope production market and due to the general sensitivity of the nuclear industry regarding public scrutiny. Can doctors help? Information about national demand for molybdenum-99 would be pivotal. Since this is the most widely used medical isotope, the amount of irradiated HEU could be estimated from its cosumption rate. And the released activity of xenon-133 could be estimated as well.

Index – 7 steps  Global stocks of HEU  Civilian use of HEU  Conversion from HEU to LEU  HEU in Targets for medical isotope production  Radioxenon monitoring for the CTBT  Global radioxenon emission inventory  Mo-99 key for HEU reduction and CTBT verification

Index – 7 steps  Global stocks of HEU  Civilian use of HEU  Conversion from HEU to LEU  HEU in Targets for medical isotope production  Radioxenon monitoring for the CTBT  Global radioxenon emission inventory  Mo-99 key for HEU reduction and CTBT verification

Global stocks of HEU National stocks of highly enriched uranium as of mid-2007 Source: Second Report of the International Panel of Fissile Material (IPFM); Global Fissile Materials Report 2007; Significant Quantity: 1 SQ = 25 kg

Index – 7 steps  Global stocks of HEU  Civilian use of HEU  Conversion from HEU to LEU  HEU in Targets for medical isotope production  Radioxenon monitoring for the CTBT  Global radioxenon emission inventory  Mo-99 key for HEU reduction and CTBT verification

Civilian use of HEU HEU consumption in civilan steady-state research reactors (Top 20) – 2007 Source: IPFM-Report- Ole Reistad, Morten Bremer Mærli; Non-Explosive Nuclear Applications Using Highly Enriched Uranium, Conversation and Minimization towards 2020, in publication progress 2007 (Reistad et.al., 2007)‏

Civilian use of HEU Core-size in HEU-fuelled reactors (Top 20 annual consumption – 2007)‏ (Reistad et.al., 2007)‏

Index – 7 steps  Global stocks of HEU  Civilian use of HEU  Conversion from HEU to LEU  HEU in Targets for medical isotope production  Radioxenon monitoring for the CTBT  Global radioxenon emission inventory  Mo-99 key for HEU reduction and CTBT verification

Conversion of civilian use of HEU to LEU Reduced Enrichment for Research and Test Reactors (RERTR) program to convert from HEU to LEU fuel started in years later?

Conversion of civilian use of HEU to LEU Number of converted HEU-fuelled research reactors and associated HEU consumption (cumulative) (Reistad et. al., 2007)‏

Shut-down of civilian HEU reactors Number of shut-down HEU-fuelled civilian staedy-state research reactors (cumulative) and associated HEUconsumption (kg) (Reistad et.al., 2007)‏

Civilian use of HEU Number of operational HEU-fuelled civilian steady-state research reactors distributed by nominal power, amd associated HEU consumption (kg) (Reistad et.al., 2007)‏ HEU consumption: 1600 → 900 kg/y

Military and civilian use of HEU HEU consumption in research reactors, propulsion reactors (1978 – 2007) and Mo-99 production (Reistad et.al., 2007)‏ HEU use: kg/y

Index – 7 steps  Global stocks of HEU  Civilian use of HEU  Conversion from HEU to LEU  HEU in Targets for medical isotope production  Radioxenon monitoring for the CTBT  Global radioxenon emission inventory  Mo-99 key for HEU reduction and CTBT verification

99 Mo production using HEU targets

95-99% of all 99 Mo is produced by irradiation of highly enriched uranium (HEU) targets less than 5 % of the global 99 Mo production is derived from the irradiation of low-enriched uranium (LEU) targets

99 Mo production facilities using HEU targets 8000Ci/week10 000Ci/week 5000 – 6000Ci/batch (several batches per week)‏ Production [3] 10% [1] -15% [2] 25% [1] 20% [1] -30% [2] 40 % [1] Production capacity (% of world demand)‏ 1. Safari I (South Africa)‏ 1. HFR (The Netherlands)‏1. BR-2 (Netherlands)‏ 2. Osiris (France)‏ 3. HFR (The Netherlands)‏ (4. HFR (France))‏ 1. NRU (Canada)‏ (2. Maple I and II (Canada))‏ Research Reactor for target irradiation South AfricaNetherlandsBelgiumCanadaCountry Necsa/NTPMallinckrodt MedicalIRE FleurusMDS NordionGeneral Informations [1] Henri Bonet and Berbard David; National Institute for Radioelements (IRE) - Fleurus - Belgium and Bernard Ponsard; Nuclear Research Centre (CEN-SCK) - Mol - Belgium; Production of Mo 99 in Europe: Status and Perspectives, ENS RRFM 2005; Transaction Session 1, 9 th International Topical Meeting; Research Reactor Fuel Management; April 2005 [2] Charles D. Ferguson, Tahseen Kazi, Judith Perera: Commercial Radioactive Sources: Surveying the Security Risks; Occasional Paper No.11; Monterey Institute of Internatonal Studies, Center for Nonproliferation Studies; January 2003 [3] IAEA-TECDOC 1051; Management of radioactive waste from 99 Mo production; November 1998 Table 1: Major production facilities for molybdenum-99

Conversion from HEU to LEU in isotope production IAEA Coordinated Research Projects (CRP) “Production of Mo-99 Using LEU Fission or Neutron Activation” Provide interested countries with access to non- proprietary technologies and methods to produce Mo-99  using LEU foil or LEU mini-plate targets  utilizing (n,gamma) neutron activation, e.g. through the use of gel generators

Conversion from HEU to LEU in isotope production None/largeBWXT (USA)‏USA (initiated by ANL)‏Homogenous reactors Small/mediumKazakhstan, RomaniaIndiaGel-technology (activation of Mo)‏ Small/largeUSA (MURR), Romania, Chile, Pakistan, Libya BATAN (Indonesia) (initiated by ANL)‏ LEU foil target and modified Cintichem process Small/largeCNEA (Argentina) ANSTO (Australia)‏ CNEA (Argentina) (initiated by ANL)‏ LEU dispersion plate targets Current/future production scale Potential producersOrigin of technologyLEU Technology Table 2: Main non-HEU production technologies of Mo-99 (Reistad et. al., 2007)‏

HEU in Targets for medical isotope production Projected Mo-99 production, target size and U-235 consumption in research reactors – based on 10% annual growth and market size figures for 1996 and 2005 (Reistad et.al., 2007)‏ Almost no information available → crude estimate → need better data

Index – 7 steps  Global stocks of HEU  Civilian use of HEU  Conversion from HEU to LEU  HEU in Targets for medical isotope production  Radioxenon monitoring for the CTBT  Global radioxenon emission inventory  Mo-99 key for HEU reduction and CTBT verification

Radioxenon monitoring for the Comprehensive Nuclear-Test-Ban Treaty (CTBT)‏ Facilities of the CTBT International Monitoring System International Monitoring System  337 Einrichtungen des International Monitoring System darunter 80 Messstellen für atmosphärische Radioaktivität  International Data Centre (IDC) zur Datenauswertung  Global Communications Infrastructure (GCI) für Datenaustausch Purpose Facilities of the CTBT International Monitoring System

Radioxenon isotope characteristics Separation line Reactor domainTest domain INGE data Critical area: Signal caused by isotope production

Index – 7 steps  Global stocks of HEU  Civilian use of HEU  Conversion from HEU to LEU  HEU in Targets for medical isotope production  Radioxenon monitoring for the CTBT  Global radioxenon emission inventory  Mo-99 key for HEU reduction and CTBT verification

Global radioxenon emission inventory

A Mo-99 production plant can release in the order of GBq/a

Global radioxenon emission inventory

Comparison of annual xenon-133 emisssions: European reactors: 0.27 PBq North American reactors: 0.26 PBq A single Mo-99 production plant can release in the order of 1 PBq

Index – 7 steps  Global stocks of HEU  Civilian use of HEU  Conversion from HEU to LEU  HEU in Targets for medical isotope production  Radioxenon monitoring for the CTBT  Global radioxenon emission inventory  Mo-99 key for HEU reduction and CTBT verification

Mo-99 key for HEU reduction and CTBT verification In order to study the HEU and xenon issues, detailed information would be required. Unfortunately, the companies and national authorities are very cautious in providing any data, in order to protect proprietary interests in light of a highly competitive isotope production market and due to the general sensitivity of the nuclear industry regarding public scrutiny. Can doctors help? Information about national demand for molybdenum-99 would be pivotal. Since this is the most widely used medical isotope, the amount of irradiated HEU could be estimated from its cosumption rate. And the released activity of xenon-133 could be estimated as well.

Conclusion Mo-99 production has impact on nuclear arms control: Danger of nuclear proliferation through use of nuclear weapons material HEU (highly enriched uranium)‏ Reactor fuel Target material Interference with verification of the CTBT (Comprehensive Nuclear-Test-Ban Treaty)‏ Isotopic signature in the nuclear test domain Single sources as large as all regional reactors together