As environmental responsibility – or at least a semblance of such – continues to seep into the core values of companies around the world, the use of recycled materials has dramatically risen in importance. This is especially true for food processors and the packaging industry, which are traditionally material-intensive sectors.

In March this year, however, the mainstream media highlighted a potential public health risk stemming from this eminently popular eco-friendly practice. Word started to spread that potentially harmful mineral oils contained within recycled cardboard packaging were able to transfer to dry food products inside. Some studies have linked the build-up of these chemicals with organ damage and even cancer, although there is still insufficient data for these links to be substantiated – all solid data comes from studies on rats. The primary food products under threat are cereals, dried pasta and rice, but any recycled food contact material is potentially at risk.

The source of these concerns was a study led by Dr Koni Grob at the Food Safety Laboratory of the Canton of Zurich, Switzerland. The element of the report that was highlighted by the international media was the fact that potentially harmful mineral oils, also called mineral hydrocarbons, were detected in many samples of dry food packaging made from recycled cardboard (119 samples were taken from the German market), and that in many cases these chemicals were able to migrate from the packaging to the food inside. The study highlighted that much of the transferred mineral oil could be sourced back to ink from recycled newspapers. 

Most alarmingly, the study noted that mineral oil levels detected were frequently between 10 and 100 times higher than acceptable daily intake (ADI) levels set by international bodies like the World Health Organisation (WHO). It should be noted, however, that no legal ADI levels for mineral oils have been set thus far, and all levels set are simply guidelines.

“The source of these concerns was a study led by Dr Koni Grob at the Food Safety Laboratory of the Canton of Zurich.”

Mineral oils: gauging the risk

Although media outlets have been emphasising the potential health risk of mineral hydrocarbon migration into foods, with some more sensationalist tabloids employing phrases like “Cornflakes Cancer Scare” in headlines, but in truth a lack of data about mineral oils and the threat they pose to public health is hindering a clear view on the topic.

Awareness of the transfer of mineral hydrocarbons into food from packaging isn’t a recent development. Nor is it specific to recycled cardboard. In January 2003, the UK’s Food Standards Agency (FSA) published a report entitled “Mineral Hydrocarbons in Food Contact Materials”. FSA’s survey found that mineral hydrocarbons were present in 42 of 64 samples of food contact materials (not just recycled card), and in many cases migrated to the food contained within.

However, the report concluded that this transfer did not represent a risk to the public. “Migration of mineral hydrocarbons into food is not a health concern,” the study noted. “Consumer intakes of wax and oil migrating into food were within ranges of Acceptable Daily Intakes set by the European Union’s Scientific Committee for Food and Joint FAO/WHO Expert Committee on Food Additives.”

Even Grob has stressed that the Swiss report is only an early step in ascertaining whether mineral oil absorption in humans is a risk in humans. “One month or less has no real effect, so there is no emergency” he told reporters. “Consumers should not make any rapid changes. We have to think about it.”

“Awareness of the transfer of mineral hydrocarbons into food from packaging isn’t a recent development.”

Grob’s belief that more work needs to be done has been echoed by food organisations in the UK. The FSA said that it is currently “gathering information” on mineral oils in the UK food market, but noted that so far there was no evidence to suggest a threat to public safety or health.

Furthermore, in response to our enquiries FSA spokesperson Emer Timmins emphasised that there are many types of mineral oils, only some of which have recommended ADIs. “The Swiss researcher used the lowest possible acceptable daily intake when setting the migration limit in his own research (0.6mg/kg of food) and applied it to all mineral oils even though the research does not identify the types of mineral oils present.”

The industry responds

Even if Grob’s study simply represents the first foray into a little-explored public health topic, comment and pre-emptive action has come thick and fast since March. According to reports by the BBC, the German Government is requesting packaging manufacturers and affected food producers to take immediate action and is even considering mandatory limits to mineral oil levels in food contact packaging.

Food and Drink Foundation (FDF) director of food safety and science Barbara Gallani responded to the study in March. “The Food Standards Agency has indicated that there is not a need for immediate action,” she said. “It is carrying out a survey of food packaging materials including recycled cardboard and will report back in the summer. In the meantime FDF has revised guidance for food manufacturers on recycled carton board in food packaging.”

“Recycling is an important pillar of the industry’s green commitments, and a delicate balance must be struck between consumer safety and environmental responsibility.”

FDF is currently not being drawn on the specifics of these new guidelines. Spokesperson Nicki Hunt responded to our request for further information: “The new guidance and the information contained within it has been circulated to FDF members and is not available more widely at present. It has been developed by the FDF Food Safety and Science team and its overarching advice is to review packaging on a case by case basis in line with industry best practice.”

Companies have responded with various degrees of assertiveness. After all, recycling is an important pillar of the industry’s green commitments, and a delicate balance must be struck between consumer safety and environmental responsibility. Many believed that cereal producer Jordans switched to Forestry Stewardship Council-certified cardboard in response to the perceived risks associated with recycled board. The company’s initial statement debunked this rumour, however. “The latest research emerging from Switzerland on the content of recycled board is relatively new and Jordans did not change to use accredited board specifically in response to this issue,” the company said. “However, we will be discussing improved supply of recycled board that avoids content from newspapers with the industry and our suppliers.”

Other brands such as Weetabix and Kellogg’s have also released statements expressing the desire to find packaging alternatives that limit the migration of mineral oils while remaining compatible with recycling. According to a statement by Kellogg’s, “While experts tell us there’s no immediate health concern, we are looking at our packaging. We are working with our suppliers on new packaging which allows us to meet our environmental commitments but will also contain significantly lower levels of mineral oil. We are also looking at alternative inner liners for our packets.”

Although no companies have yet gone into any detail about how they plan to reduce mineral oil content in packaging or block the chemical’s migration into food, the study noted that one of the only materials effective in disrupting migration was aluminium, a revelation that may herald a widespread shift toward foil-based inner linings once clearer regulatory guidance on mineral oils is released.

Given that all experts agree there is no immediate emergency, it’s clear that many affected companies are attempting to bide their time and wait for more thorough data to emerge, while also ensuring the public that they are exploring this issue with due seriousness. It’s equally clear that Dr Grob’s study was merely the first drop in a river of research that remains to be completed on mineral oils and their relationship with dry foods and, indeed, the health of the human body. Until then, the industry is making the right noises and waiting for the results.