The tests revealed 'contamination' with the metal, known to hinder brain development and cause potentially fatal lung damage

Traces of methylmercury, which is particularly dangerous for pregnant women and children, were found in nearly all tins of tuna purchased in France, Italy, Spain, Germany and Britain, in the study

A warning has been issued that some cans of tuna contain a toxic metal, leading people to say they are 'scared' and have thrown tins away - but doctors have previously said it's fine in moderation