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.
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