A recent study revealed nitrites in all 21 tested processed meat products from major retailers, with Wiltshire ham exhibiting the highest concentrations, for instance, 33mg/kg in Tesco's version.
Although present, the nitrite levels in all analysed products were found to be below the 150mg/kg legal limit set in the UK and EU.
Cancer Research UK estimates that around 13 per cent of the 44,100 bowel cancer cases diagnosed annually in the UK are associated with processed meat consumption.
While nitrites are used for preservation, experts highlight the availability of less harmful alternatives, though some supermarkets, like Tesco, state their products comply with legal limits and safety requirements.