An expert in radioactivity measurements told ITV News that while he believes the scientists who concluded Arafat was poisoned did a "thorough and careful job" and considered factors that could impact their findings, the seven-year delay makes the statistical certainty of their conclusions "limited".
The number of polonium atoms which were initially present at the time of his death would have reduced by a factor of at least one million compared to what could be measured now, seven years later...thus any radioactivity from such a sample would be much harder to measure now compared to a time period closer to his time of death.
The measurements are further complicated by the fact that 210-Polonium is present in measurable amounts in the natural background radiation in the earth's crust and in normal, healthy biological materials such as human bone.
– Paddy Regan, Professor of Radionuclide Metrology at Surrey University
The widow of Yasser Arafat, Suha, has described how weak the former Palestinian leader was before his death after it was revealed that scientists have found a high level of polonium 210 in his exhumed body.
Mrs Arafat said: "Words can't express my deep sorrow and the sorrow of my daughter, but mostly the anger - we are so angry. It's a political crime, a political assassination. It is so hard, we are mourning him again."
Suha Arafat, the widow of the late Palestinian leader said: "When they came with the results, I’m mourning Yasser again. It’s like you just told me he died. I will not stop. Me and my daughter will go to all courts in all over the world to punish who did this crime."
Some experts have questioned whether Arafat could have died of polonium poisoning, pointing to a brief recovery during his illness which is not consistent with radioactive exposure. They also noted he did not lose all of his hair.
But Professor David Barclay said neither fact was inconsistent with the findings.
Since polonium loses 50% of its radioactivity every four months, the traces in Arafat's corpse would have faded so far as to have become untraceable if the tests had been conducted a couple of years later, Professor Barclay said.
Arafat fell ill in October 2004, displaying symptoms of acute gastroenteritis with diarrhoea and vomiting. At first Palestinian officials said he was suffering from influenza.
He was flown to Paris in a French government plane but fell into a coma shortly after his arrival at the Percy military hospital in the suburb of Clamart, where he died on 11th November.
The official cause of death was a massive stroke but French doctors said at the time they were unable to determine the origin of his illness and no autopsy was carried out.
Polonium- 210 was responsible for the death of defecting Russian spy Alexander Litvinenko in 2006 after it was slipped into a cup of tea in a London hotel. From his deathbed, Litvinenko accused Russian President Vladimir Putin of ordering his murder.