In an earlier post, I linked to this video interview with Arafat's personal physician, who said that Yasser Arafat had AIDS.
A month before that interview, Arafat's fellow terrorist Ahmed Jibril, the head of the PFLP-GC (Popular Front for the Liberation of 'Palestine' - General Command) told Hezbullah's al-Manar television that Arafat had AIDS. You can find that interview here.
Viewed in context, the entire claim that Israel poisoned Arafat is part of a 'Palestinian' blood libel in which the 'Palestinian people' have never been given another narrative. Most 'Palestinians,' who view no media other than their own, have never heard anything other than 'the Israelis murdered Arafat.'
You can find a history of the Israel murdered Arafat libel here.