Recycled packaging used for food products may pose a health risk, according to a BBC investigation.

Cereal firms such as Jordans, Kelloggs and Weetabix are said to be taking action to reduce the amount of potentially harmful chemicals found in recycled cardboard.

The chemicals, known as mineral oils, are found in the ink used in newspaper publishing. Newspapers are a prominent part of the recycled materials used in food packaging.

Swiss scientists have found that food manufacturers have often included between 10 and 100 times the agreed limit of mineral oils in their packaging, despite links being found with the inflammation of internal organs and cancer.

Jordans has stopped using recycled packaging altogether, whilst other firms are looking to reduce the risks from the chemical, which was found to pass through the protective inner bags of cereal packaging in one German study.

The Food and Drink Federation has suggested the Swiss study was a "good starting point," but further evidence was needed to justify discontinuing the use of recycled cardboard.