As the body of iconic Palestinian leader Yasser Arafat is exhumed and tested for polonium poisoning, SBS takes an in-depth look at the rare radioactive substance itself.
Although the outcome of the tests on Arafat's remains won't be known for a while, polonium has been used in assassinations throughout history.
What is polonium? And why is it used in assassinations?
WHAT IS POLONIUM?
Polonium is a naturally occurring radioactive material found in very low concentrations in the environment. It was the first element to be discovered by physicist and chemist Marie and Pierre Curie.
Polonium is produced during the natural decay of uranium, but it can also be manufactured artificially by bombarding the element bismuth with neutrons in nuclear reactors. According to Al-Jazeera, Russia produces most of the world's supply of polonium.
There are more than 25 isotopes of polonium, with polonium-210 (Po-210) being one of the most common types. High levels of polonium-210 were found on the clothing of deceased Palestinian leader, Yasser Arafat.
Polonium-210 releases 'alpha' particles which means it travels at a very short distance, whilst retaining most of its radioactive energy. The World Health Organisation (WHO) reports that it is 5,000 times more radioactive than radium. It has a half-life of 138 days.
According to the WHO, Po-210 is not a health risk if it remains outside the body, since it can't penetrate through surfaces like paper or skin. Most traces of the substance can be removed via thorough hand-washing and showering. You will not be contaminated if you are simply exposed to the substance.
WHY CAN IT BE USED AS A POISON?
Po-210 is a radiation risk if it is inhaled, ingested or contaminates a wound. About 45 per cent of Po-210 gets into the spleen, liver, kidney, and 10 per cent remains in bone marrow. Only a small amount is needed for it to be deadly.
Because alpha radiation travels at a short distance, it is relatively hard to detect, which makes it easy for those in possession of the substance to slip under the radar. However, only a few countries are known to have large reserves of the radioactive substance, so in theory, it wouldn't be difficult to deduce responsibility for Po-210 poisoning.
WHAT ARE THE SYMPTOMS?
Severe radiation poisoning from Po-210 is similar to the remaining stages of cancer: nausea, vomitting, diarrhoea, hair loss, yellowing of the skin, loss of white blood cells, and failure of vital organs like the kidneys and liver.
CASES OF POLONIUM POISONING
In 2006, Russian dissident Alexander Litvinenko was allegedly poisoned by Po-210 after he had tea with two Russians in a London hotel. The former KGB agent accused Russian president Vladimir Putin of being behind the attack before he died a few days later.
Polonium is also believed to have killed French scientist Irene Joliot-Curie (Marie Curie's daughter), and two employees working on Israel's nuclear program.
