A03026: Investigation of the migration of inorganic contaminants into dry food from packaging made from recycled paper and board
Wednesday 18 June 2003
This research project aims to establish whether there is a need for a safety review with respect to inorganic contaminants in recycled paper and board in contact with dry food.
Study Duration: June 1999 to May 2000
Contractor: Imperial College of Science, Technology and Medicine
Background
Recycling of wastepaper is believed to increase the concentrations of metals in the recycled product. Although it is generally assumed that there is no risk of migration of chemical contaminants from recycled paper and board into dry food, there is some evidence that this might occur. Therefore it is important to carry out research on whether migration occurs into all or only certain types of dry food; which elements migrate and to what extent. This study was carried out to determine the presence of inorganic contaminants in recycled paper and board, which is intended for contact with dry foods; to investigate whether there is migration into these foodstuffs; and to determine whether they are potentially of concern to human health.
This purpose of this project is to establish whether there is a need for a safety review with respect to inorganic contaminants in recycled paper and board in contact with dry food.
The first objective was to compare the concentrations of trace elements in the recycled paper and board used in contact with dry food with those found in virgin paper and board packaging, to see if the concentrations are higher in recycled material. The second objective was to investigate whether there is migration of trace elements from recycled paper and board packaging into dry food. Finally a dry food ‘simulant’ (a chemical compound used to mimic the behaviour of real food in a migration test) was investigated.
Research Approach
Twenty samples of recycled paper and board packaging, used in contact with dry food were obtained through manufacturers and retailers. Twenty samples of virgin paper and board used in contact with dry food were also collected for comparison. Products included flour, rice, pulses, cereal, biscuits, salt, fruit and pasta. Samples of recycled paper and board were also obtained direct from the paper mill. The samples were analysed using a very sensitive, multielemental technique for the detection of trace elements down to very low concentrations. Samples of the paper and board were analysed to determine 64 elements in total, including those of physiological/ toxicological interest.
Following analysis, the samples were tested for migration of the elements by keeping the food in contact with the packaging for a period of up to 90 days. Ten examples of packaging with potential for migration were selected for the study, with products including salt, rice, oats, tea, fruit, pasta, fries and pizza. The food was tested for signs of migration at regular intervals: (1, 8, 21, 30, 60 and 90 days). At the end of the contact period of 90 days the foods were shaken vigorously to see if any physical abrasion of the packaging might enhance migration.
Results and findings
In general the concentrations of all the elements in recycled paper and board packaging are higher than those found in virgin paper and board, and closely reflect the values obtained from the samples of recycled paper and board provided by the mill. The concentration factor for the recycled samples appears to be around tenfold. However, the physical nature of the paper and board also affects the concentration of elements regardless of their origin, indicating that additives used in the manufacturing process also have a role to play.
Samples of rice, oats, custard powder, mushrooms and fries showed traces of zinc and iron migration from the packaging. The amount of iron and zinc found in the food was between 0.02 and 0.04% of the recommended daily intake for these elements considered necessary for a healthy human diet.
Finally the food simulant was tested, to establish whether it could be used to mimic the behaviour of food. There as no measurable migration of zinc into the simulant but the zinc migrating into food was close to the detection limit of the method so the test was not conclusive.
The project has shown that recycled paper and board does contain higher levels of many elements compared to virgin paper ad board. However, there was no appreciable migration of the elements in recycled paper and board packaging into food, on 90 days storage at ambient temperature, or when the packaging is shaken.
Dissemination information
Final report is available from the FSA Library and Information centre. To obtain a copy, please contact the Enquiry Desk, Dr. Elsie Widdowson Library and Information Services, Food Standards Agency (020 7276 8181/8182 or at library&info@foodstandards.gsi.gov.uk).
See Also