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Recent studies estimate that tyre and road wear particles (TRWP) are the largest single source of synthetic polymer particles in the microscopic size range (1 to 1000 µm). Fourier transform infrared (FTIR) spectroscopy has been widely used for microplastic (MP) identification. However, as tyre particles contain black carbon, the infrared light is absorbed causing a potential under-reporting of TRWP. To overcome this limitation, the attenuated total reflection (ATR) mode could be an alternative for strongly-absorbing samples. Due to the complex chemical composition of TRWP, specific markers are needed to detect them in the environment. Several inorganic and organic tyre components have been proposed e.g., metals as Zn or organic compounds as benzothiazoles. The accurate quantification of TRWPZn is limited by the presence of other Zn-species and particulates in the matrix. Therefore, a density separation is required to isolate this TRWPZn fraction, considering that TRWP have higher densities than "classic" MP. In this study, a chemical characterisation of tyre wear (TW) and tyre wear particles (TWP) is presented using spectroscopic methods. Several used vehicle classes tyres were collected, shredded and sieved to generate a ¡ 1 mm TWP fraction. ATR-FTIR was explored to generate an in-house TW/TWP spectra library for future identification. Elemental analysis of individual TWP and a composite sample (TWPmix) was conducted using ICP-MS after microwave digestion. Furthermore, salts of different densities were evaluated for the isolation of TRWPZn. The developed method will support the environmental monitoring of TRWP, providing a more comprehensive characterization of these particles. This work was supported by the EU Funding for Research&Innovation (H2020-LABPLAS project, Ref. 101003954-H2020-SC5-2020-2) and by the Galician Government (Ref. ED431C 2021/56). M.E.C.B. also thanks the Next Generation EU and the Spanish Government for her María Zambrano Grant (RSU.UDC.MZ08). J.T.B. acknowledges Xunta de Galicia for his postdoctoral Grant (ED481B-2021-090). Also see: https://micro2022.sciencesconf.org/426806/document, In MICRO 2022, Online Atlas Edition: Plastic Pollution from MACRO to nano

The presence of plastic additives in the marine water, some of them classified as toxic substances and included in REACH, has gained concern in the last decades. Plastic additives include a wide range of substances with different physical-chemical characteristics, including substances that acts as plasticizers, ignifugants, antioxidants, UV filters, or antimicrobials. The development of an automatic, sensitive robust and reliable analytical method for the analysis of these kind of substance becomes essential for the marine water quality monitoring. In this work, an arrow solid-phase microextraction method with gas chromatography and tandem mass spectrometry determination, was optimized for the analysis of 48 plastic additives comprising phthalates, organophosphate flame retardants, benzotriazoles, benzophenones, bisphenols, adipates, etc... Univariate and multivariate approaches were used in order to optimize the parameters: desorption time, percentage of organic modifier, split vent time and flow, extraction time and temperature. Other parameters were fixed previous to the optimization (fibre, incubation time, desorption temperature, sample salinity...). Once all the parameters were optimized, the analytical performance characteristics of the method were calculated for all the compounds. The sensitivity was different depending on the compounds, varying the quantification limit between 0.0017µg L-1 (DiBP) and 81 µg L-1 (TCEP). Good recoveries, between 70 and 130% for all the analytes except vitamin E (57%), with a good precision (relative standard deviation Also see: https://micro2022.sciencesconf.org/426810/document, In MICRO 2022, Online Atlas Edition: Plastic Pollution from MACRO to nano

Polypropylene is one of the most produced plastics in the world which is eventually discarded into the environment. Once released, plastics may degrade through several agents, as formation of biofouling in the polymer surface that can alter the weathering process affecting their flotability, or slowing photochemical degradation through light screening. In the frame of the MicroplastiX project (JPI Oceans) 9 different polymers, were exposed to marine environment throughout the summer season in Ría de Ares, A Coruña. Samples were subsampled at T0, T7, T15, T30, T60 and T90 days of exposition. This study focuses on the characterization of the changes that biofouling growth produces in polypropylene using ATR-FTIR, identifying new bands in its spectrum and studying how this process interferes with natural weathering and with the identification in monitoring studies of plastics and microplastics. Measurements of biofouled and non-biofouled PP are made after soft digestion (10% H2O2, 40ºC) to identify the origin of the new bands in their IR spectra. Moreover, SEM microscopy was also done in order to study the changes caused by biofouling growth or natural weathering, and even to identify some of the organisms growing on the surface of the plastic. Preliminary results indicate that biofouling growth is visible in the spectrum within a few weeks of exposure to the marine environment, producing, at T90, a significant change in the ATR-FTIR spectrum. It also appears that, the growth of biofouling on the surface of the polymer exerts a protection against ageing (mainly photo-oxidation). Acknowledgements: MicroplastiX (Grant PCI2020-112145) supported by JPIOceans Program, MCIN/AEI/10.13039/501100011033 and European Union "Next Generation EU"/PRTR"; LABPLAS (Grant H2020- 101003954) and "ChemPlas" Project supported by the Agencia Estatal de Investigación (Grant PID2019- 108857RB-C31/AEI/10.13039/501100011033). The Program 'Consolidación e Estructuración de Unidades de Investigación Competitivas" (Xunta de Galicia) is also acknowledged (Grant ED431C 2021/56). Also see: https://micro2022.sciencesconf.org/426870/document, In MICRO 2022, Online Atlas Edition: Plastic Pollution from MACRO to nano

The number of studies dealing with microplastics pollution in the atmosphere is increasing. But sampling methods and sample treatment protocols are not standardized yet and, so, comparison of results is hardly possible. Some kind of general-use methodology would be welcome, mostly to monitor what is going on with the atmosphere at different places of the World. On the other hand, a relatively novel instrumental technique based on the use of Quantum Cascade Lasers in the IR spectral region (LDIR) offers nice possibilities to perform monitoring although some parameters need further optimization. In the present work 2 different passive sampling methods were tested: a commercial system known as Depobulk (with a 22 cm diameter aperture) and another home-made one (with a 11 cm diameter aperture) to evaluate their collection capabilities. Also, 3 digestion methods (two alkaline-oxidative and an oxidative one) were assessed, with good results, both, but with important operational differences. In addition, we have optimised some parameters of the LDIR measurement: 1) we propose an automatic classification system for fibres and particles with a hit rate higher than 93%; 2) to be stricter to get positive matches between the spectra of the unknowns and the databases in order to avoid false positives (which have been found in different polymers). Finally, we studied the atmospheric deposition of MPs (dry and wet) in a sub-urban area NW of Spain, classified in different particle size ranges. The results showed a mean value of 500 MP/day/m2 with a relevant number of MPs in the smaller 50-20 µm fraction (400 MP/day/m2), especially polyurethane, polyethylene and polypropylene. Support: European Union LABPLAS project (Grant H2020- 101003954) and Program of Consolidation and Structuring of Units of Competitive Investigation SUG (Xunta de Galicia) cofinanced by ERDF-Operative Program of Galicia 2021-2024 (ED431C 2021/56). Also see: https://micro2022.sciencesconf.org/426898/document, In MICRO 2022, Online Atlas Edition: Plastic Pollution from MACRO to nano