Media retracts reports on Zinc in canned food based on flawed data

Recently there had been a number of media reports claiming high levels of Zinc in canned foods together with claims of adverse health effects. These were prompted by a scientific paper published in the journal Food and Function which is seriously flawed, miscalculating the concentration of Zinc in canned foods quoting figures up to 500 times the actual levels which are, in fact, well below any level of concern.

The journal Food and Function have now officially retracted the article "ZnO nanoparticles affect intestinal function in an in vitro model" which was published early April 2018. The article can be downloaded here.

The Royal Society of Chemistry (RSC) which is responsible for the journal Food and Function had published an “Expression of Concern” regarding the flawed content of the scientific paper warning that the data in the paper is “unreliable”. This was the first stage in retracting the article due to its flaws.

The flaws in the study have also been fully recognised in a report on the NHS (UK National Health Service) website which confirms the Metal Packaging Europe Food Contact Commission expert findings regarding the paper.

As well as the gross error in calculating the concentration of Zinc in canned food samples, the paper also assumed, without basis, that all the Zinc found in the food is in the form of Zinc Oxide nanoparticles and that it comes from the can internal coating.

Zinc Oxide is used by the metal packaging manufacturing industry in some cans as a fully approved internal coating pigment/additive to avoid unsightly staining of the metal substrate with certain sulphur containing foods. It is not used in can coatings for its antimicrobial properties as stated in the paper.