Assurance of safety of recycled paperboard for food packaging through comprehensive analysis of potential migrants is unrealistic

• Safety for food application means absence of toxic compound.
• Safety would presuppose comprehensive analysis of potential migrants.
• With the method applied, more than 250 potential migrants were detected.
• For roughly 2/3 of the substances a tentative identification was possible.
• Recycled paperboard contains too many substances for this approach to be realistic.

A method for determining potentially health-relevant components in paperboard used for packaging dry foods as comprehensively as technically feasible was applied to a sample of recycled paperboard. The task was specified by a detection limit in food of 0.01 mg/kg, from which a detection limit of 0.1 mg/kg in paperboard was derived. Extracts from the paperboard were preseparated into seven fractions by high performance liquid chromatography (HPLC) and transferred on-line to gas chromatography with flame ionization detection (GC-FID). The chromatograms visualize the high complexity of the material that may migrate into foods at toxicologically potentially relevant concentrations. Since only a minority of the substances was also detectable in fresh fiber board, most must have originated from chemicals used in the paper and board fed into the recycling process. Significant variability between recycled paperboards of four manufacturers was observed because of varying feedstocks. Using comprehensive two-dimensional GC (GC × GC) with time of flight mass spectrometry (TOF-MS), more than 250 substances were counted that probably exceeded the detection limit and were probably of sufficient volatility for migration into dry food. It is concluded in three main messages to risk managers: (i) since most potential migrants have not been adequately evaluated, many not even identified, the safety required by Article 3 of EU Regulation 1935/2004 has not been ensured; (ii) the number of substances potentially migrating into food above 0.01 mg/kg is too large to realistically be brought under control; (iii) a barrier reducing the migration into food by a factor of 100 over the life time of a product would keep the migration of all except a few well known substances below 0.01 mg/kg in food.