The discovery of traces of Polonium-210 -- a radioactive agent -- on clothing reportedly worn by Yasser Arafat in his final days reignited a slew of conspiracies Wednesday about his mysterious death that occurred in 2004.

Francois Bochud, who heads the Institute of Radiation Physics in Lausanne, Switzerland, which was commissioned by Arafat's widow to conduct tests, told the Associated Press on Wednesday that his lab had discovered "very small" quantities of polonium-210, which is naturally present in the environment. But levels found in blood and urine samples taken from the clothing were well above normal.

Bochud said an "elevated" level of more than 100 millibecquerel, a measurement of radioactivity, was found on Arafat's belongings. That's compared with levels of some 10 millibecquerel in some control samples.

He said Arafat's wife told him she had stored the items in her lawyer's office after her husband died. It was not clear why she waited so long to test them. NPR too has voiced its opinion on some questionable, or at least unclear, facts from Al Jeezera's original report on the investigation:

[...] two things stand out to us in the al-Jazeera report:

— The clothing and other effects, according to Arafat's widow, had been stored at her lawyer's office since shortly after his death nearly eight years ago. That raises questions about who had access to them.

— Al-Jazeera writes that "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. 'Even in case of a poisoning similar to the Litvinenko case, only traces of the order of a few (millibecquerels) were expected to be found in (the) year 2012,' the [Institut de Radiophysique in Lausanne, Switzerland] noted in its report to Al Jazeera. But Arafat's personal effects, particularly those with bodily fluids on them, registered much higher levels of the element. His toothbrushes had polonium levels of 54mBq; the urine stain on his underwear, 180mBq."

Here's what we don't get:

Why would the polonium-210 levels still be so high if Arafat had been poisoned with the radioactive element so long ago?

Bochud stressed that the discovery did not provide proof that Arafat had been poisoned. That would require further testing.

Still, what do U.S. military experts think? The Special Operations Forces Report (SOFREP) reports a source with black side intel saying it is "most likely" the case that Arafat was assassinated. The source doesn't expound upon whether he or she thinks Polonium-210 was the cause though.

Just what is Polonium-210 and what does it do? Polonium-210 is one of the world's rarest elements, discovered in 1898 by scientists Marie and Pierre Curie and named in honor of her country of origin, Poland. It occurs naturally in very low concentrations in the Earth's crust and also is produced artificially in nuclear reactors. In small amounts, it has legitimate industrial uses, mainly in devices to eliminate static electricity.

If ingested, it is lethal in extremely small doses. Less than 1 gram (0.04 ounces) of the silver powder is sufficient to kill. A 2007 study by radiation experts from Britain's Health Protection Agency concluded that once polonium-210 is deposited in the bloodstream, its potent effects are nearly impossible to stop. A poisoning victim would experience multiple organ failure as alpha radiation particles bombard the liver, kidneys and bone marrow from within.

Scientists caution that traces on Arafat's clothing aren't sufficient proof of poisoning. Exhuming his body would a surer method. Derek Hill, a radiological science expert at University College London, said eight years after Arafat's death in 2004, any polonium would have decayed and would be far less radioactive than it was at the time. But he says it would still be much higher than normal background levels, and with an autopsy it should be possible to tell "with a pretty high confidence" whether Arafat had polonium in his body when he died.

In terms of next steps after testing, if Arafat's death is confirmed an assassination by polonium-210, the world will be asking "who did it?" SOFREP has some speculation on this topic:

[...] who would have access to this element? Even though this type of assassination was a signature KGB move,  you don’t have to look to far to see who else has nuclear capability and would be motivated most to kill Arafat.  The Mossad is very good at this, just look at the Dubai assassination and the Mossad’s mission.

Watch Al Jazeera's report on the investigation to learn more of the details (Note: It's about 50 minutes long):

The Associated Press contributed to this report.