A new method for faster analysis of chemicals in paper and board food packaging materials has been developed in a PhD project at the National Food Institute, Technical University of Denmark. The method can be used to increase existing knowledge of which chemicals in packaging materials are potentially harmful.
Paper and board is used extensively in food packaging materials e.g. in baking paper, microwave popcorn bags and cereal packaging, which come into direct contact with the food. Despite the extensive use of this type of packaging there is only limited knowledge about both the chemical composition of the packaging and the toxicological effects of these chemical substances.
Screening strategy developed
In her PhD project at the National Food Institute, Linda Bengtström has developed a screening strategy, which can be used to examine and assess the safety of food packaging materials made from paper and board. In the screening chemical substances are first extracted from the packaging materials. The substances are then separated into smaller fractions, and the toxicity of the fractions is measured in several in-vitro cell assays.
This makes it possible to focus on the fractions, which potentially contain endocrine disrupting or carcinogenic substances. These ”toxic” fractions are separated into individual substancesand the harmful substances are identified through mass spectrometry.
Mass spectrometry is a very sensitive and accurate method of analysis, which can determine molecular mass and structure. In the mass spectrometer, the individual molecules are broken into smaller fragments, which are characteristic of the specific chemical, whereby it is usually possible to identify the chemical.
New database of chemical substances
To make it easier and faster to identify the individual substances in the packaging, Linda Bengtström has built a database of more than 2,100 chemical substances, which have previously been found in board and paper. In the future the aim is that the database is incorporated in the mass spectrometric analysis to further automate the identification of the individual substances which would otherwise be done manually.
Harmful compounds detected
Using her screening method Linda Bengtström has found board and paper packaging containing compounds with endocrine disrupting effects, which originated from contaminated recycled fibers and from glue used in new fibers.