An article published on April 12, 2017 in the peer-reviewed journal Food Additives & Contaminants: Part A investigated the presence of several bisphenols in paper and cardboard products made of virgin and recycled fibers.
The authors Jurek and Leitner from the Institute of Analytical Chemistry and Food Chemistry, Graz University of Technology, Graz, Austria, developed a sensitive analytical method based on gas chromatography (GC) – tandem mass spectrometry (MS/MS) to measure bisphenol A (BPA, CAS 80-05-7) and its analogues bisphenol AF (BPAF, CAS 1478-61-1), bisphenol B (BPB, CAS 77-40-7), bisphenol E (BPE, CAS 2081-08-5), bisphenol F (BPF, CAS 620-92-8), and bisphenol S (BPS, CAS 80-09-1).
The analyzed products included six different paper and board samples used in the production of food and hygiene packages. The samples were obtained in 2015 directly from different European paper and board manufacturers. Three of these products were made of fresh fiber, and three contained an unknown proportion of recycled content.
All target bisphenols, except BPAF and BPB, could be detected at least in some of the analyzed samples. The limit of detection for BPAF and BPB was 0.23 and 0.35 µg/kg, respectively. Products with recycled content had up to 9’641 µg/kg and up to 106 µg/kg BPA and BPS, respectively. These concentrations were much higher than in two virgin fiber products, which contained up to 112 µg/kg BPA, and BPS below the limit of quantitation. However, the third virgin product showed a relatively high content of BPA and BPS, namely 3’179 µg/kg and 11 µg/kg, respectively. This was attributed to the presence of an organic lining on one side of this product. The content of BPF and BPE was comparable in both virgin and recycled products, reaching up to 83 µg/kg for the former and up to 6.8 µg/kg for the latter.
The significant content of BPA analogues demonstrates that “there is a beginning process of the substitution of BPA by other bisphenols,” the authors noted. BPS could also be introduced during recycling, particularly from thermal paper.
Calculation of potential migration according to the ‘worst-case’ scenario (100% migration assumed) showed that all measured concentrations were well below the specific migration limits for BPA and BPS. This indicates that the products analyzed in this study “can be assumed to be safe regarding the migration of bisphenols,” the authors concluded.
Jurek, A., and Leitner, E. (2017). “Analytical determination of bisphenol A (BPA) and bisphenol analogues in paper products by GC-MS/MS.” Food Additives & Contaminants: Part A (accepted author version posted online April 12, 2017).