Ham and bacon sold in major UK supermarkets contain cancer-causing chemicals

Supermarket giants including Tesco and Marks and Spencer have come under fire for selling ham and bacon containing cancer-causing chemicals. Wiltshire ham has been singled out as the product with the highest levels of nitrites, following an analysis that pitted it against cooked ham and unsmoked bacon. Despite WHO declaring in 2015 that nitrites are unsafe, all 21 meat products tested in a recent laboratory study were found to contain the preservatives.

Tesco's Wiltshire ham topped the charts with a staggering 33 milligrams of nitrites per kilogram - compared to 2.88mg/kg in its own cooked ham and 8.64mg/kg in its unsmoked bacon. It also far exceeds the 1.84mg/kg detected in Morrisons's bacon. Other brands' Wiltshire hams, such as those from M&S (28.6 mg/kg), Sainsbury's (21.1mg/kg), and Morrisons (19.2mg/kg) also contained high nitrite concentrations, although Asda's version was comparatively lower at 8mg/kg.

Campaigners calling for a nitrite ban have branded these findings "alarming". Cancer charities are urging the public to minimise processed meat consumption, linking it to an increased risk of bowel cancer.

According to Cancer Research UK, processed meat could be responsible for 13% of the 44,100 bowel cancer cases diagnosed annually in Britain.

The new research, conducted by Food Science Fusion and laboratory specialists Rejuvetech, revealed that nitrite levels in all 21 products remained well beneath the 150mg/kg legal threshold.

Coalition Against Nitrites, which commissioned the analysis, said: "It's nearly a full decade since the WHO classified nitrite-cured processed meats as a group one carcinogen and it is disappointing and alarming that we continue to see products on sale containing high levels of nitrites.

"Consumers are increasingly aware of the dangers of nitrites in processed meats, yet they continue to be exposed to their risks."

Wiltshire ham contains such high nitrite concentrations due to its manufacturing method, where pork receives nitrate injections, similar to cooked ham preparation.

It's then soaked in a brine and nitrite solution, providing its colour while safeguarding against lethal bacteria. During this stage, nitrates are converted into nitrites.

Several food companies, including Finnebrogue and Waitrose, have taken steps to address growing concerns about nitrites by offering bacon that is free of them.

A Tesco spokesperson said: "We follow all UK and EU requirements, alongside guidance from the UK Food Standards Agency, to ensure we get the right balance of improving the shelf life and safety of our products with limited use of additives.

"The nitrites levels in all of our products, including our traditionally cured Finest Wiltshire ham, fall significantly below the legal limits in the UK and EU.

"Nitrates and nitrites are an important part of the curing process for some meats and they are used to prevent the growth of harmful bacteria that cause serious food poisoning."