Swiss scientists this week reported that they found high concentrations of polonium in body fluids on items used by late PLO arch-terrorist Yassir Arafat before his death in 2004.
The announcement rekindled accusations that Arafat may have been poisoned. Many have named Israel as suspect one. But what is polonium?
Polonium, also known as Radium F, is a rare but naturally occurring metalloid found in uranium ores that emits highly-hazardous positively-charged particles.
Before being cited this week as a possible factor in Arafat’s death, Polonium came to prominence in the case of Alexander Litvinenko.
Litvinenko, a former Russian spy and dissident, died in a London hospital in 2006 showing symptoms of polonium poisoning.
Small doses of polonium 210 exist in the soil and atmosphere, and even in the human body, but in high doses it is highly toxic and can deal severe damage to the body's tissues and organs, especially if it is ingested or inhaled.
It is one of the rarest natural elements: in 10 grams of uranium there is a maximum of a billionth of a gram of polonium.
Safe doses of Polonium are used industrially for its alpha radiation (positive charge) in research and medicine, and as a heating source for space components.
Small doses are also found in tobacco, derived from the soil and phosphate fertilizers used on tobacco plants.
However, Polonium can be fatal even in relatively minute doses if it is ingested or inhaled, which is what many believed happened to Arafat.
It has also been opined the late PLO leader may have died of AIDS or cancer, but French authorities have yet to release his medical files due to stringent privacy laws.
Marie and Pierre Curie in 1898 discovered polonium while they were doing research in France on the cause of radioactivity in the mineral pitchblende, the chief ore-mineral source of uranium.
For their discovery of polonium, radium and their work on radioactivity, the Curies won the 1903 Nobel Prize in Physics. It was shared with Antoine Becquerel of France.