Identification of volatile compounds from polyolefin used for food packaging

Identification of volatile compounds from different virgin polyolefin FCMs was carried out by GC-MS with both HS-SPME and ultrasonic extraction (UE), with the aim to obtein the most amount of volatile compounds from polyolefin. Seventy compounds were identified with 90% reliability by GC-MS with NIST 14 library, most of them are NIAS.                   &nbsp

The migration of NIAS from ethylene-vinyl acetate corks and their identification using gas chromatography mass spectrometry and liquid chromatography ion mobility quadrupole time-of-flight mass spectrometry

An exhaustive migration study of eight corks, made of ethylene–vinyl acetate, was carried out to identify any non-volatile and volatile compounds using an untargeted approach. The challenge associated with the structural elucidation of unknowns was undertaken using both ultra-high-performance liquid chromatography coupled to an ion-mobility separation quadrupole-time of flight mass spectrometer and gas chromatography mass spectrometry. A total of fifty compounds were observed to migrate from the corks, and among these additives such as antioxidants (Butyl 4-hydroxybenzoate, Irganox 1010, Irganox 1075, Irgafos 168 and BHT) or lubricants (EBO and octadecanamide, N,N'-1,2-ethanediylbis-) were identified. A high proportion (84%) of the detected compounds was non-intentionally added substances (NIAS), and included several cyclic oligomers with different chain sequences. NIAS, such as 2,6-bis(1,1-dimethylethyl)-4-ethyl and 7,9-ditert-butyl-1-oxaspiro[4.5]deca-6,9-diene-2,8-dione, break-down products, including hexa-, hepta- and nonadecanamide, N,N'-1,2-ethanediylbis-, and oxidation products were also identified. One cork was found to be unsuitable for use as a food contact material

Migration of contaminants from printed masks for children to saliva simulant using liquid chromatography coupled to ion mobility-time of flight-mass spectrometry and gas chromatography-mass spectrometry

The COVID-19 pandemic has led to children using polymeric FFP2 and polymeric surgical masks on a daily basis. Children often bite and suck on such masks as they wear them closed to their mouths. In this work, the migration of contaminants from printed and unprinted children`s masks to a saliva simulant has been studied. Liquid chromatography coupled to ion-mobility quadrupole time-of-flight mass spectrometry has been used for the detection and identification of non-volatile migrants. An orthogonal projection to latent structures – discriminant analysis (OPLS-DA) was applied to compare the data from the printed masks against the data from the unprinted ones. Headspace solid phase microextraction coupled to gas chromatography mass spectrometry was used to assess the migration of volatile compounds. Thirteen compounds were found in the masks with concentrations ranging from 5 ng/g to 254 ng/g. Toluene, chlorobenzene, irganox 1076 and 2-(2-butoxyethoxy)ethyl acetate were all found to migrate from the masks studied. Moreover, differences between the migrants from printed and unprinted FFP2 masks were found. Octocrylene, 4-(dimethylamine)benzoate, methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate and tris(3-methylphenyl)phosphate were found to migrate only from printed masks. Toluene that migrated from all the masks studied and tris(3-methylphenyl)phosphate, that migrated only from printed masks, have been listed as hazardous priority substances

Prediction of Collision Cross-Section Values for Extractables and Leachables from Plastic Products

The use of ion mobility separation (IMS) in conjunction with high-resolution mass spectrometry has proved to be a reliable and useful technique for the characterization of small molecules from plastic products. Collision cross-section (CCS) values derived from IMS can be used as a structural descriptor to aid compound identification. One limitation of the application of IMS to the identification of chemicals from plastics is the lack of published empirical CCS values. As such, machine learning techniques can provide an alternative approach by generating predicted CCS values. Herein, experimental CCS values for over a thousand chemicals associated with plastics were collected from the literature and used to develop an accurate CCS prediction model for extractables and leachables from plastic products. The effect of different molecular descriptors and machine learning algorithms on the model performance were assessed. A support vector machine (SVM) model, based on Chemistry Development Kit (CDK) descriptors, provided the most accurate prediction with 93.3% of CCS values for M + H](+) adducts and 95.0% of CCS values for M + Na](+) adducts in testing sets predicted with <5% error. Median relative errors for the CCS values of the M + H](+) and M + Na](+) adducts were 1.42 and 1.76%, respectively. Subsequently, CCS values for the compounds in the Chemicals associated with Plastic Packaging Database and the Food Contact Chemicals Database were predicted using the SVM model developed herein. These values were integrated in our structural elucidation workflow and applied to the identification of plastic-related chemicals in river water. False positives were reduced, and the identification confidence level was improved by the incorporation of predicted CCS values in the suspect screening workflow

A collision cross section database for extractables and leachables from food contact materials

The chemicals in food contact materials (FCMs) can migrate into food and endanger human health. In this study, we developed a database of traveling wave collision cross section in nitrogen ((CCSN2)-C-TW) values for extractables and leachables from FCMs. The database contains a total of 1038 (CCSN2)-C-TW values from 675 standards including those commonly used additives and nonintentionally added substances in FCMs. The (CCSN2)-C-TW values in the database were compared to previously published values, and 85.7, 87.7, and 64.9% M + H](+), M + Na](+), and M - H](-) adducts showed deviations <2%, with the presence of protomers, post-ion mobility spectrometry dissociation of noncovalent clusters and inconsistent calibration are possible sources of CCS deviations. Our experimental (CCSN2)-C-TW values were also compared to CCS values from three prediction tools. Of the three, CCSondemand gave the most accurate predictions. The (CCSN2)-C-TW database developed will aid the identification and differentiation of chemicals from FCMs in targeted and untargeted analysis

Identification of Polyamide 6 and Polyamide 66 Oligomers Using Ion Mobility Time-of-flight Mass Spectrometry and Risk Assessment Study of Their Migration from Kitchenware to Foodstuff

Ion mobility time-of-flight mass spectrometry has been used for the identification the PA 6 and PA 66 oligomers through their accurate m/z, CCS values and fragmentation pattern. An extraction method for the oligomers from sunflower oil, cooked beans, soup and whole milk has been developed with recoveries ranging from 87 to 102 %

Application of Ion Mobility-High Resolution Mass Spectrometry and In Silico Tools for Identifying Non-Volatile Substances in Food Contact Material

The use of ion mobility separation (IMS) in conjunction with high-resolution mass spectrometry has proved to be a reliable and useful technique for the characterization of small molecules from food contact materials (FCMs). Collision cross section (CCS) values derived from IMS can be used as a structural descriptor to aid compound identification. One limitation of the application of IMS to the identification of chemicals from FCMs is the lack of published empirical CCS values, thus, this thesis firstly established a CCS database for extractables and leachables from FCMs. On the other hand, many chemicals in FCMs don't have commercial standards, their experimental CCS values cannot be obtained, in this case, machine learning approaches were used to build the models to predict the CCS values for chemicals in FCMs. A support vector machine (SVM) model, based on Chemistry Development Kit (CDK) descriptors, provided the most accurate prediction with 93.3% of CCS values for [M + H]+ adducts and 95.0% of CCS values for [M + Na]+ adducts in testing sets predicted with Besides the CCS values, the retention time (RT) is also very important for the unknown identifications. therefore, we also developed a prediction model to generate the predicted RT values. Based on the in-silico RT and CCS prediction models, a workflow to identify nonvolatile migrates from FCMs was proposed using liquid chromatography-ion mobility-high-resolution mass spectrometry. This workflow was evaluated by screening the chemicals that migrated from polyamide spatulas, we found that the predicted RT and CCS values can reduce the number of candidates and increase the confidence of identification in targeted and suspect screening analysis. The development of a database containing predicted RT and CCS values of compounds related to FCMs can aid in the identification of chemicals in FCMs.<br /

ESTUDIO DE MIGRACIÓN DE COMPUESTOS DESPRENDIDOS DESDE PAJITAS DESECHABLES DE PAPEL

Se trata de un estudio donde se identifica y cuantifica los compuestos migrados desde pajitas de papel a alimentos (gaseosa). Se emplea la cromatografía de gases con SPME para su análisis. Como conclusión, se compara la cantidad migrada con la legislación correspondiente para verificar su legalidad.<br /

Aptitud sanitaria de materiales reciclados para contacto alimentario.

Los materiales para contacto alimentario contienen múltiples aditivos en su composición. Ciertas sustancias que los componen pueden acabar formando parte del alimento o generando otras sustancias no intencionadamente añadidas que cambien las propiedades del envase o del alimento debido a su migración al mismo, por ello es de vital importancia poder analizar los migrantes y ver que los niveles de sustancias que podrían ser tóxicas, no superan los límites establecidos por la legislación vigente. En este trabajo se optimiza un método analítico para poder cuantificar dos tipos de aminas generadas a partir de la reacción de los diisocianatos provenientes de un adhesivo utilizado en corchos con el agua contenida en bebidas alcohólicas. El objetivo es crear un método analítico con una alta selectividad debido a que se va a trabajar con matrices complejas (alimento). El método deberá tener además alta sensibilidad para poder detectar trazas de los migrantes. La técnica empleada es la cromatografía líquida de ultra-alta resolución (UPLC) acoplada a un espectrómetro de masas tipo triple cuadrupolo. <br /

Estudio De Sustancias No Volátiles Procedentes De Materiales Reciclados Para Contacto Alimentario

Hoy en día, las cuestiones medioambientales son de una importancia global. Entre ellas destaca el tema de los plásticos y su excesivo uso y producción en masa. Es por ello por lo que el reciclaje y la reutilización de plásticos es de vital relevancia para evitar la producción de nuevos plásticos y favorecer la economía circular.Este trabajo de fin de grado se centra en el estudio de migración de sustancias contenidas en polietileno de alta densidad (HDPE) reciclado utilizado para la fabricación de envases de leche. Como simulante alimentario de la leche para los ensayos de migración se ha utilizado etanol al 50% en agua. Los análisis se han realizado mediante cromatografía liquida, concretamente cromatografía de ultra alta resolución acoplada a espectrometría de masas tipo cuadrupolo y analizador de tiempo de vuelo (UPLC-MS-QTOF). El estudio se había iniciado previamente con identificación de compuestos no volátiles en extractos del HDPE reciclado. En este trabajo se identificaron los compuestos que habían migrado al simulante, y se llevó a cabo su cuantificación.Por una parte, se observa que, a mayor porcentaje de material reciclado en el envase, la contaminación en las muestras es mayor. Por otro lado, no se superan los límites legales establecidos para ningún contaminante, así que no se compromete la seguridad alimentaria de los consumidores.Por todo esto, he de destacar que el reciclaje y reutilización de este tipo de plásticos es una alternativa viable y un punto muy importante en la producción presente y futura de la industria del plástico.<br /