Yasser Arafat
Yasser Arafat Israel news photo: Flash 90

Swiss experts confirmed over the weekend that they had found traces of polonium on clothes belonging to former Palestinian Authority leader Yasser Arafat. The experts said that the findings suggested that Arafat may have been poisoned with the substance; Arafat's wife Suha has long insisted that this was the case.

The findings were published in the British medical journal The Lancet. In interviews, the experts said that they had found polonium traces on Arafat's clothing and other belongings. Arafat died in 2004 at age 75 from unspecified causes, and no autopsy was done on his body. Interest in whether or not Arafat was poisoned skyrocketed after Russian ex-spy and Kremlin critic Alexander Litvinenko was poisoned with polonium in  2006.

Polonium is a highly radioactive element used, among other things, to power spacecraft. Animal studies have found similar symptoms, which lingered for weeks - depending on the dosage – until the subject died. “The primary radiation target… is the gastrointestinal tract,” said an American study conducted in 1991, “activating the ‘vomiting center’ in the brain stem.”

Polonium-210, the isotope found on Arafat's belongings, has a half-life of 138 days, meaning that half of the substance decays roughly every four-and-a-half months, leading many observers to express skepticism at the possibility that Arafat was poisoned - the levels of the isotope on Arafat's belongings are far higher than what scientists would expect after nearly a decade of decay.

But samples of Arafat's personal effects tested in 2012 showed significantly higher levels of polonium than levels that would appear naturally. Based on computer models, the experts said that the samples they had examined indicated that Arafat could have been a victim of mass polonium poisoning, measured perhaps in the billions of becquerels, a radioactivity measuring unit. Naturally occurring polonium only registers a few millibecquerels, usually fewer than 10, at a time.

However, even though the tests indicate Arafat may have been poisoned, they do nothing to suggest who may have been behind it.