Tins of soup contain dramatically higher amounts of Bisphenol-A (BPA), a chemical linked to cancer and impaired sexual development, than those containing no canned ingredients.
Drinking one can per day for a five-day period raises the amount of BPA in the urine by 1,221 per cent, a study by Harvard scientists published in the Journal of the American Medical Association showed.
The chemical, which is used in the lining of tin cans as well as hard plastic containers such as water bottles, has also been associated with male infertility, behavioural and emotional problems in girls, and an increased risk of heart disease, stroke and diabetes.
Researchers divided 75 people into two groups and asked one to eat a tin of soup every day for five days, while the other was told to eat soup containing no tinned ingredients. After a two-day break, the groups’ diets were switched.
Jenny Carwile, who led the study, said: “We’ve known for a while that drinking beverages that have been stored in certain hard plastics can increase the amount of BPA in your body. This study suggests that canned foods may be an even greater concern, especially given their wide use.”
A separate survey by the Food Standards Agency found that BPA was found in 37 of 62 common supermarket products tested by scientists, including Princes tinned ham, Sainsbury’s fruit cocktail in syrup, Heinz baked beans and Tesco baby carrots.
Levels of the chemical were within official safety limits, but scientists remain uncertain over whether lower levels could pose a health threat.
Moira McMillan, chief executive of the British Coatings Federation, which represents companies making the linings of food cans, admitted the industry was ‘at a loss’ to explain the high levels found in the tinned ham, but said there was no threat to consumers.
A Food Standards Agency spokesperson said: “The Food Standards Agency bases its advice on the body of scientific evidence and the opinion of independent scientists.
“Our current advice is that BPA from food contact materials does not represent a risk to consumers but the Agency will be looking at this study, as it would at any new piece of work, to see if it has any implications for our advice to consumers.”