Source and further detail: Belfast Telegraph

Thanks for drawing that to our attention rebbonk,
We read about that and read labels, additives etc. Anything with Aspartame and carrageenan in we don't buy for the reasons you stated. I don't know why the WHO allows those kind of additives.
Colds and Flu powders like Lemsip also contain Aspartame. Never purchase these either. But its possible you can now get these Flu powders without Aspartame, I don't know as we don't buy it .

Aspartame has been suspect for at least 40 years. How one proves toxicity, especially, over decades of use is difficult to say.
Then how do you prove causation? Experiments are not done on humans. So, if product X is dosed at a thousand times the level it would ever be given to a human and is found to cause malignancy in, say, mice, then yes there might be a link. If you take in equally large amounts. And you are a mouse. Bertrand Russell even denied there was any such thing as causation. Even today it cannot be said the smoking causes disease. All we can say is that it comes as close to being a cause as it is scientifically possible to be.

From the reports I've been listening to, this is only part of the story. The next stage is to work out what the safe/dangerous levels of consumption are.