Improving forensic investigation for polonium poisoning.

At the time of publication, the remains of Yasser Arafat have been exhumed and are being investigated for cause of death as a result of the fi ndings of the case reported here. On Nov 11, 2004, Arafat died at the age of 75 years of an unidentifi ed illness in Percy Hospital, France. He presented with a medical history that began in Ramallah on Oct 12, 2004, with nausea, vomiting, abdominal pain, and diarrhoea. Shortly after, his general health deteriorated with continuing gastrointestinal symptoms, thrombocytopenia, apyrexia, but the absence of infl ammation and myelosuppression. On Oct 29, he was admitted to Percy Hospital. He had diarrhoea, nausea, vomiting, and generalised abdominal pain with mild liver and kidney failure that was associated with dissem inated intravascular coagulation syndrome. His condition worsened, with acute renal failure, aggravation of a cholestatic jaundice, and neurological coma. He was transferred to the intensive care unit, where he died of a cerebral haemorrhage. Despite numerous toxicological and clinical investigations, the cause of his illness remained unknown. There was no evidence of infectious, vascular, or cancerous disease and the treatment had been symptomatic only. Poisoning was considered but never confi rmed by toxicological analyses. After the death of Alexander Litvinenko in 2006, 210Polonium (210Po) poisoning was considered as a possible cause of Arafat’s death. Although the absence of myelosuppression and hair loss does not favour acute radiation syndrome, symptoms of nausea, vomiting, fatigue, diarrhoea, and anorexia, followed by hepatic and renal failures, might suggest radioactive poisoning. From a medico-legal perspective, this hypothesis is justifi ed given the absence of a characterised cause of illness and the absence of toxicological evidence, including γ radiations, as well as the dearth of scientifi c literature in this topic. In February, 2012, Arafat’s widow made his medical records and his late belongings available to us. DNA analysis (see appendix) confi rmed that the belongings were Arafat’s. Toxicological elemental analyses done on his hair were unremarkable. Further investigations on several belongings did not reveal any known poison. To assess the possibility of 210Po ingestion, we focused our radiotoxicological analyses on visible body fl uid stains from specifi c belongings (underwear, chapka, toothbrush, hospital cap, sportswear). We did 210Po analyses on 75 samples, 38 of them taken from Arafat’s belongings (see fi gure in appendix). The remaining 37 samples were references, which were not artifi cially contaminated with 210Po. These included cotton items that had been kept for 10 years and protected from dust and products of radon decay in an attic (appendix). Several samples containing body fl uid stains (blood and urine) contained higher unexplained 210Po activities than the reference samples. These fi ndings support the possibility of Arafat’s poisoning with 210Po. According to biokinetic modelling (see appendix), the measured activities of 210Po of several mBq per sample are compatible with a lethal ingestion of several GBq in 2004. Moreover, his clinical presentation could not rule out 210Po poisoning. Although myelo suppression and hair loss are expected in acute radiation syndrome after whole-body external exposure, these symptoms are poorly docu mented in the case of internal exposure of ingested 210Po. In radionuclide therapy, side-eff ects include nausea, vomiting, fatigue, and abdominal pain, with hair loss being less common. Toxicity can occur in bone marrow and, to a lesser extent, kidneys and liver. Myelosuppression varies greatly between patients. In Arafat’s case, low marrow cellularity associated with ageing and non-bone-seeking biodistribution of 210Po might have attenuated myelosuppression. Since ingested 210Po is eliminated primarily through faeces, the gastrointestinal syndrome, associated with multiple organ failure, could be a pre dominant cause of death. The fact that around 20 half-lives had elapsed was clearly a challenge for measurement of 210Po. However, on the basis of this forensic investigation, there was suffi cient doubt to recommend the exhumation of his body in 2012. Three scientifi c teams are currently analysing body, shrine, and earth samples. Because of legal procedures, the date of publication of the detailed results of the exhumation analyses is unknown. An autopsy would have been useful in this case because although potential polonium poisoning might not have been identifi ed during that procedure, body samples could have been kept and tested after wards. The international medical community should continue to consider toxicological analyses of body samples in cases presenting with unknown cause of death.