Study of hotmelt adhesives used in food packaging multilayer laminates. Evaluation of the main factors affecting migration to food

Abstract

Hotmelt adhesives are widely used in the manufacture of multilayer laminates, commonly used as food packaging materials. For this reason, it is very important to determine the composition of the adhesives and to identify which compounds could migrate from the laminate to the food. Twenty four compounds were identified in 2 different hotmelt adhesives, some of them with high toxicity levels according to theoretical model of Cramer, such as 9,10-dihydroanthracene and retene. Some physicochemical properties of these compounds, such as their partition and diffusion coefficients in the different materials used in the laminates, provide useful information for evaluating their potential migration to the food. The determination of the partition and diffusion coefficients was performed with two different laminates made of cardboard or polypropylene cardboard substrates and the adhesive. Partition and diffusion coefficients of the migrants in the adhesives and substrates were calculated from the experimental results. It was found that diffusion was always lower in the adhesive than in the cardboard. All diffusion coefficients determined increased with temperature while the partition coefficients showed the opposite effect. Migration results confirmed that the migration value of a compound was closely related to the calculated partition and diffusion coefficients. None of the migrants exceeded the recommended Cramer exposure values.

Analytical tools for identification of non-intentionally added substances (NIAS) coming from polyurethane adhesives in multilayer packaging materials and their migration into food simulants

“…The first step in the analysis was the extraction of the compounds from the adhesives and the individual films used as substrates. Volatile and semivolatile compounds were extracted and analyzed directly by HS-SPME-GC-MS, following the procedure previously optimized by Nerín et al [6], Vera et al [4], and Aznar et al [3]. Due to the wide range of potential compounds with different polarities likely present in these samples, the mixed fiber PDMS-DVB was selected.…”

“…Recommendations about adhesives for food packaging materials are also reported by BfR (Bundesinstitut für Risikobewertung) in Germany [15]. Additionally, the EU Project MIGRESIVES (Research Programme on migration from adhesives in food packaging materials in support of European legislation and standardization) provided scientifically based risk assessment of the use of different compounds in adhesives and created a mathematical model for predicting the migration of adhesive compounds into food, which could form a basis for future specific EU legislation [1][2][3][4][5][6]16].…”

“…Again, this time, the use of MS as detector was essential for the identification of unknowns, and further quantification was achieved. Vera et al [4] identified 24 volatile and semivolatile compounds in a previous screening carried out by SPME-GC-MS in two different hotmelt adhesives, in which alkanes and BHT, among others, migrated from cardboard packaging and polypropylene (PP) laminated cardboard, glued with these hotmelt adhesives, into Tenax®. Liquid extraction and further injection into gas chromatography-mass spectrometry (GC-MS) confirmed the identification.…”

“…Although a small amount of adhesive is used (up to 5 %) [1], it can provide more than 4,000 different substances as potential migrants to be transferred into food in contact with the packaging. Therefore, the risk of adhesives in food safety is a real issue [2][3][4][5][6].…”

UPLC–ESI-Q-TOF-MSE and GC–MS identification and quantification of non-intentionally added substances coming from biodegradable food packaging

“…The migration study was done with poly(2,6-diphenyl-pphenylene oxide) (Tenax®) following the procedure optimized in previous work [25][26][27]. The cutouts of each multilayer, 5 cm×5 cm, were placed in Petri dishes and covered with 1 g of Tenax®, forming a uniform layer (4 g Tenax® per square decimeter of laminate in accordance with UNE-EN 14338 [28]).…”