Table 3.
Studies published in the literature on by-products/side reaction products (NIAS) Identification in different plastic food packaging.
| Food Contact Material | NIAS | Method/Technique | Reference |
|---|---|---|---|
| Active packaging: Polypropylene (PP); PP + green tea; PP/poly (ethylene-co-vinyl alcohol) EVOH; PP/EVOH + oregano; PP/EVOH + citral; EVOH; Polyethylene terephthalate-PET/EVOH + citral; PET/EVOH + cinnamon; PP/EVOH/PP; PP/EVOH + oregano | Degradation of active compounds; impurities from the raw materials; additives used in the manufacture of the active polymer (citral thermal reaction products; oxidation product of citral; decomposition product of adipates used as plasticizers; impurity/reaction product/breakdown product for the additives used in the manufacture of PE materials; xanthenone derivates) | UPLC-QTOF-MS | [86] |
| Polyurethane adhesives in multilayer packaging materials | By-product of the polyester-based urethane 91,6-Dioxacyclododecane-7,12-dione); cyclic adipate; unknown nitrogen-compounds; unknown phenolic compounds; 1,4,7-Trioxacyclotridecane-8,13-dione | HS-SPME-GC-MS | [67] |
| Polyethylene terephthalate (PET), oriented polyamide (OPA), cast polypropylene (CPP), polyethylene (PE) and PE/ethyl vinyl alcohol PE(EVOH) | Primary aromatic amines-PAAs (1,8-diazacyclotetradecane-2,9-dione; caprolactam; 1,8,15-triazacycloheneicosane-2,9,16-trione; 1,3-bis(isocyanatomethyl)-cyclohexane, 1-cyanodecane and 1,4-bis(isocyanatomethyl)-cyclohexane; l-leucyl-l-leucyl-l-leucine; 1,4,7,18,21-pentaoxa-11,14,25,28-tetraazacyclohentriacontane (9CI); l-leucine; l-leucyl-l-leucyl-l-leucyl-l-leucyl-; butanediamide; N4-hydroxy-N1-[(1S)-2-methyl-1-(1-pyrrolidinylcarbonyl)propyl]-2-pentyl-, (2R)-; triethylamine, naphtylethylenediamine; 1,8,15,22-tetraazacyclooctacosane-2,9,16,23-tetrone; urea; N-cyclohexyl, urea, N-cyclohexy-N′-methyl and 1-(cyclohexycarbonyl)piperazine); Dimethyl phthalate | UHPLC–Q-TOF/MSE | [69] |
| Silicone moulds and teats | Side reactions in the polymerization (cyclic and linear polydimethylsiloxanes; oligomeric dimethyl siloxanes) | H-NMR and GC-MS | [89] |
| Multilayer plastic materials (polyethylene (PE) and low-density polyethylene (LDPE) plus nylon | By-products-cyclic ester oligomers made of the monomers adipic acid (AA), phthalic acid (PA), diethylene glycol (DEG), monoethylene glycol (MEG) and neopentilglycol (NPG) | LC-HRAMS and LC-ESI-Q-TOF-MS | [98] |
| Polypropylene food storage containers | By-product Benzothiazole | GC × GC−ToF MS | [77] |
| UV-curable varnishes over polypropylene | 2-propenoic acid,1,1′-[2-[[3-[2,2-bis[[(1-oxo-2-propen-1-yl)oxy]methyl]butoxy]-1-oxopropoxy]methyl]-2-ethyl-1,3-propanediyl] ester is considered a NIAS, as it is a reaction product coming from the monomer TMPTA, 11-diethyl-7-oxo-4,6,10,12-tetraoxopentadecane-3,13-diyl diacrylate | GC-MS/Q and UHPLC-IMS/QTOF | [68] |
GC(×GC)-(EI)TOFLRMS: two-dimensional gas chromatography-electron ionization time-of-flight high-resolution mass spectrometry; GC-MS: gas chromatography-mass spectrometry; H-NMR: Proton nuclear magnetic resonance spectroscopy; HS-SPME-GC-MS: a combination of headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry; LC-ESI-Q-TOF-MS: liquid chromatography-electrospray ionization mass spectrometer quadrupole time of flight; LC-HRMS: liquid chromatography high-resolution mass spectrometry; UHPLC–Q-TOF/MSE: ultra-performance liquid chromatography coupled with a hybrid quadrupole time-of-flight mass spectrometry; UPLC IMS/QTOF: ultra-performance liquid chromatography-ion mobility separation-quadruple time-of-flight; UPLC-QTOF-MS; UPLC–MS(QTOF): ultra-performance liquid chromatography–quadrupole time of flight mass spectrometry.