From BBC News:
The artificial sweetener aspartame is not linked to cancer, according to a report just released by the European Food Safety Authority (EFSA). The European food watchdog undertook an urgent review of the additive following a study, published in 2005, which suggested aspartame was carcinogenic. But a working party said the incidence of tumours could not be linked to the artificial sweetener.
Dr Iona Pratt, chair of AFC’s working group, said: “The Ramazinni Foundation’s study showed an increase of cancers of the blood – lymphoma and leukaemia – in the rats.” But, she said, the working group concluded that these tumours were not related to aspartame. AFC said the rate of the tumours was not related to the dose of aspartame, which would have been expected if there was a link. The working group believes that a respiratory disease, found in many of the rats that took part in the study, was the likely cause of the tumours.
More here.