An Italian laboratory has said there is no proof vegetables are behind the E.coli outbreak.
It comes as the death toll in Europe from the outbreak has now risen to 19, after an 80-year-old woman died in Germany.
Up to 1,800 people in twelve countries are infected.
It is thought the source is probably something that women eat more than men, given that more women have been infected.
Agriculture Minister Simon Coveney is expected to join EU colleagues for talks on the poisoning, later this month.
More in this section