Analytical methods for the screening of potential volatile migrants from acrylic-base adhesives used in food-contact materials

Abstract

Two different analytical techniques were studied for screening the volatile compounds present in pure adhesives and those from the adhesives in different laminates. Three different adhesive formulations were used for the study, all acrylic-based and supplied by different producers. Laminates with polypropylene and paper, polypropylene and polyethylene, and aluminium and polyethylene as substrates were prepared and studied. Adhesives themselves were acetonitrile extracted and volatiles identified by time-of-flight mass spectrometry based on accurate mass measurement of molecular and main fragments. The volatiles in the films themselves were determined by a headspace solid-phase microextraction analysis followed by gas chromatography-mass spectrometry. Significant differences were found within the adhesive formulations. Compounds detected in the screening were assessed in terms of migration through the laminate polypropylene and paper into polyethylene used as a matrix-simulating food. The concentration of the compounds in the polyethylene ranged from 0.04 to 1.6 µg dm⁻² in the polypropylene side, and from 0.27 to 28 µg dm⁻² in the paper side. The most toxic compound detected in the screening, 2,4,7,9-tetramethyl-5-decyne-4, was not found in any of the sides. Analytical features were also calculated to provide the conditions for quantitative purposes. Sensitivity was at low ng dm⁻² of polyethylene and the relative standard deviation was below 10%.

Keywords:

• chromatographic analysis
• chromatography–gas chromatography-mass spectrometry (GC/MS)
• clean-up–solid-phase microextraction (SPME)
• headspace
• additives general
• food-contact materials
• migration
• packaging

Acknowledgements

This work was supported by the European Union under the Collective Research Programme Contract No. COLL-CT2006-030 309 MIGRESIVES. The findings and conclusions in this paper are the responsibility of the authors alone and should not be taken to represent the opinion of the European Commission. Financial support was also received from Grupo Consolidado de Investigación T-10 from Gobierno de Aragón, Spain. E. Canellas acknowledges the grant from Gobierno de Aragón.