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Polonium!!!. The London Po-210 Poisoning Case: What we know and what we don’t know May 15, 2008. CAPT Michael A. Noska, USPHS Senior Health Physicist U.S. Department of Health and Human Services Food and Drug Administration Center for Devices and Radiological Health. Outline.
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The London Po-210 Poisoning Case:What we know and what we don’t knowMay 15, 2008 CAPT Michael A. Noska, USPHS Senior Health Physicist U.S. Department of Health and Human Services Food and Drug Administration Center for Devices and Radiological Health
Outline • Basic chronology of the events • Internal Radiation Dosimetry 101 • Specifics of Polonium-210 • Dosimetry for Mr. Litvinenko • Health physics, public health and criminal F/U
Chronology 11/1/2006 Litvinenko meets Russians at London hotel. Several hours later, becomes sick with vomiting. 11/4/2006 Litvinenko admitted to hospital 11/11/2006 Condition very bad. Placed under armed guard. 11/19/2006 Report of thallium poisoning. 11/21/2006 Litvinenko critical, suffers heart attack. Russians deny involvement. 11/23/2006 Litvinenko dies. 11/24/2006 Litvinenko’s statement read. Health authorities identify Po-210 as probable cause of death.
Basic Radiation Physics and Dosimetry • Types of radiation: α, β+/β-, γ/x, n • Radioactivity: (units: Ci, Bq) • Half-life • Absorbed dose: energy imparted per unit mass of tissue • Units: rad/rem, Gy/Sv 1 Gy=100 rad; 1 Sv=100 rem
Dose Parameters • Type of radiation • Amount of radioactivity • Half-life • Chemical form • Biodistribution • Biokinetics • Body/organ mass • Time of administration • Route of administration
Polonium-210 (Po-210) • Solid metal at room temperature • Dissolves readily in dilute acids • Decays by alpha particle emission “Pure alpha” • Becomes easily airborne and “creeps” due to alpha recoil energy
Po-210 continued • Uranium series decay product • Physical half-life: 138.38 days • Biological half-life: 50 days • Effective half-life: 36.7 days • Specific activity: 4490 Ci/g
Sources of Po-210 • Naturally occurring in plants and foods (tobacco) • Grazing animals concentrate in body tissues • Nuclear weapons (not currently) • RTGs for space program (not currently) • Anti-static devices (sealed sources) • Nuclear reactors Russia makes ~100 grams per year and exports ~1 gram per year to the US
Radiation Hazard • No external hazard due to very low yield gamma emission • Internal hazard due to α-particle • High LET • Distributes in soft tissue → whole body dose • Concentrates in liver, kidney, RBM, spleen and skin • Excreted via urine, feces, skin
What do we know? • Type of radiation • Amount of radioactivity • Half-life • Chemical form • Biodistribution • Biokinetics • Body/organ mass • Time of administration • Route of administration
What do we know? • Type of radiation YES • Amount of radioactivity • Half-life • Chemical form • Biodistribution • Biokinetics • Body/organ mass • Time of administration • Route of administration
What do we know? • Type of radiation YES • Amount of radioactivity NO • Half-life • Chemical form • Biodistribution • Biokinetics • Body/organ mass • Time of administration • Route of administration
What do we know? • Type of radiation YES • Amount of radioactivity NO • Half-life YES • Chemical form • Biodistribution • Biokinetics • Body/organ mass • Time of administration • Route of administration
What do we know? • Type of radiation YES • Amount of radioactivity NO • Half-life YES • Chemical form NO • Biodistribution • Biokinetics • Body/organ mass • Time of administration • Route of administration
What do we know? • Type of radiation YES • Amount of radioactivity NO • Half-life YES • Chemical form NO • Biodistribution MAYBE • Biokinetics • Body/organ mass • Time of administration • Route of administration
What do we know? • Type of radiation YES • Amount of radioactivity NO • Half-life YES • Chemical form NO • Biodistribution MAYBE • Biokinetics MAYBE • Body/organ mass • Time of administration • Route of administration
What do we know? • Type of radiation YES • Amount of radioactivity NO • Half-life YES • Chemical form NO • Biodistribution MAYBE • Biokinetics MAYBE • Body/organ mass YES • Time of administration • Route of administration
What do we know? • Type of radiation YES • Amount of radioactivity NO • Half-life YES • Chemical form NO • Biodistribution MAYBE • Biokinetics MAYBE • Body/organ mass YES • Time of administration NO • Route of administration
What do we know? • Type of radiation YES • Amount of radioactivity NO • Half-life YES • Chemical form NO • Biodistribution MAYBE • Biokinetics MAYBE • Body/organ mass YES • Time of administration NO • Route of administration NO
Retrospective Dose Assessment • Incomplete information • Assumptions (time, route of administration) • Biological samples • Biokinetic models: ICRP 30, ICRP 68, ICRP 72 • Animal data • Lethal dose (LD50/60) • Acute versus chronic dose
ICRP GI Tract Model Stomach 1 hour 4 hours SI Blood 13 hours ULI f1 = 10% for polonium LLI 24 hours Feces
Mr. Litvinenko’s Dose • He got a snootfull (Sf)! • 1-3 GBq (~25-80 mCi) • 50 mCi? • ~6 micrograms • Dose to RBM ≈ 9 Gy in three weeks • Other organs: liver (25 Gy/GBq), kidneys (40 Gy/GBq), spleen (15 Gy/GBq)* *J. Harrison et al, Polonium-210 as a poison, J. Radiol. Prot. 27 (2007), pp. 17-40.
Health Physics Response • HPA aka NRPB • Surveys • Laboratory analysis • Clean-up/remediation • Total government response (NRC, DOE, EPA equivalents)
Other Contaminated Locations • Offices • Restaurants • Coffee bars • Nightclubs • Football (soccer) stadium • Airplanes • Cars • Hotels (3 primarily)
Public Health Response (UK) • Health Protection Agency • Tracked plane passengers and anyone else who had contact with Litvinenko • Comm. plan (Website, media, call center) • Developed protocols for lab analysis and dose assessment based on urinalysis, ICRP models • Follow-up criteria: <1mSv,1 ≥EDE<6, ≥6 • 738 samples (686/35/17)
Public Health Response (US) • CDC worked closely with UK • State Department, CDC Quarantine program • Public Health message (HAN, Epi-X) • Identified labs and developed analytical plans (similar to UK) • ~100 self-reported, 24 samples analyzed All results <1mSv
The CDC Team Radiation Studies Branch Charles W. Miller, PhD Robert C. Whitcomb, PhD, CHP Armin Ansari, PhD, CHP CDR Jeffrey B. Nemhauser, MD, USPHS Carol McCurley, MS Communications Bernadette Burden, Office of the Director Dagney Olivares, National Center for Environmental Health/Agency for Toxic Substances & Disease Registry Division of Laboratory Sciences Robert Jones, PhD Division of Global Migration and Quarantine Gary W. Brunette, MD Special Thanks: John Croft, PhD, Head of Emergency Response, United Kingdom Health Protection Agency
Criminal Investigation • Poisoning suspected early, type unknown • Discovery of rad contamination (11/21) • Millenium hotel bar and sushi bar closed (crime scene and public health concern) • Easy to follow trail • Suspect identified May 2007
Conclusion • Almost the perfect crime! • Major impact both in UK and internationally • Media frenzy • View to the future? • Could it happen here? It did!
June 29, 1995 • NIH P-32 Incident • 27 people (including pregnant worker) internally contaminated with ~1-500 μCi • Laboratories and researcher’s home contaminated • Massive survey, bioassay and decontamination effort • Local event
Acknowledgement Dr. Charles Miller CDC, Radiation Studies Branch