Flexo Wash
Cleaning Technology for the Flexographic, Gravure and Offset Package Printing Industries
Food packed in recycled paperboard has got a bad press over the risk of mineral oil contamination. Nick Kernoghan, UK director of Pira International, examines the facts behind the headlines and warns the industry to take the time to find the right solutions.
On 8 March 2011, BBC Radio and the Daily Telegraph in the UK ran stories about mineral oil contamination of food packed in recycled paperboard packaging, followed on 9 March by the Daily Mail.
By the morning of 10 March a Google search on mineral oil in recycled paper and board brought up 4,430 citations. News travels fast in the modern world.
However, news does travel somewhat slower from the scientific community to the wider world.
The evidence cited in the media coverage came from two studies undertaken by the Official Food Control Authority of the Canton of Zurich, both published in the journal European Food Research and Technology.
The first study was published in February 2010 and identified the inclusion of newsprint in recycled paper and board as the main source of the mineral oil and highlighted quite high levels of migration, as well as the conflict between meeting European recycling targets and controlling migration.
The second study was published in October 2010 and analysed 119 samples of dry food packed in paperboard boxes for migration of mineral oil. Once again mineral hydrocarbons were found in all the foods packed either without an inner plastic bag or with a polyethylene bag, with saturated hydrocarbons at concentrations of 4mg/kg-28mg/kg and aromatic hydrocarbons at concentrations from 0.7 mg/kg-6.1mg/kg depending on the food type and time in contact.
Different hydrocarbons have different toxicological properties as illustrated by the list below:
It appears that it is mainly the technical grades of mineral oils that are used in newsprint and these are the main source of both the paraffinic and the aromatic hydrocarbons being found in foods packed in recycled paperboard. Other sources of mineral oils include:
Toxicological information on mineral oils indicates that they bio-accumulate in the liver, heart valves and lymph nodes and cause inflammation of these organs. Additionally, there are additional concerns of potential carcinogenicity caused by the aromatic fraction.
However, these are all long-term chronic affects and people eating a balanced diet should not suffer any adverse health consequences in the short or medium term, and maybe not in the longer term unless their exposure is particularly high. Therefore there is time to develop solutions to this problem and the industry can afford to avoid knee-jerk decisions such as switching packaging to all virgin fibre.
The German BfR carried out a risk assessment of mineral oil exposure in 2009.
They concluded that there is an urgent need to reduce the exposure from recycled paperboard, but did not introduce any specific legislation.
The Swiss authorities have concluded that consumers who eat a balanced and varied diet are safe.
In the UK the Food Standards Agency (FSA) has stated that it does not believe that the current data shows there to be a health risk to consumers who eat a balanced and varied diet, but the organisation is keeping the situation under review and carrying out research of its own.
Once again these opinions point to a conclusion that there is time to develop solutions to this problem.
There probably will not be a universal solution that fits all cases. It will vary for different combinations of pack, food and shelf life. However, possible solutions, in no particular order, include those listed here:
There are undoubtedly others, but the important thing is that industry is allowed the time to develop solutions.
Cleaning Technology for the Flexographic, Gravure and Offset Package Printing Industries
End-of-Line Casepacker, Carton Erector and Crate Packer Systems
Sustainable Packaging Paper and Board for Multiple Applications