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.
More top news
Nigel Farage said Ukip's campaign would be separate from two existing No campaigns ahead of the 2017 referendum.
Murder charges against an Irish nanny, who spent more than two years in prison accused of killing a baby in the USA, have been dropped.
Charities face probe after claims they may have been involved in buying and selling widower's details.