Plastic gradually fragments into smaller pieces forming microscopic fractions of less than 5 mm commonly known as microplastics. These microplastics have become one of the most persistent pollutants of the sea and beaches, due to their small size, their ubiquity and global distribution [1]. An estimated 80% of microplastics pollution comes from land, while about 18% of these marine debris is attributed to the fishing industry [2]. Moreover, previous studies reported up to 44% of raw pellets and values above 100g/l of sand in the coastal zones of the Canary Islands. The Canary Islands constitutes an area of accumulation of microplastics, being found this type of pollution even in beaches infrequently visited [3]. Microplastics represents a major threat to the environment due to the following reasons [4]: • Are typically hydrophobic with large surface areas and high adsorption capacity of POPs (Persistent Organic Pollutants) and PBTs (Persistent, Bioaccumulative and Toxic substances). • As they adsorb POPs, microplastics can result in a double-entry pollution vector: as a POPs vector and by the plastic itself. • High abundance and long residence time. • Absorption and ingestion by aquatic organisms and subsequent transfer to higher trophic evels. Given that microplastic is a relatively new environmental problem and their newly increased pollution levels, it is important to better understand their impact. The establishment of standardized analysis procedures for their chemical characterization is required among the scientific community. A total of 10 microplastic samples collected in the Canary Islands were optically characterized and analysed using pyrolysis-gas chromatography coupled to mass spectrometry (Py-GC/MS). The pyrolysis temperature was 400 ºC for 1 minute and the chromatographic conditions and compound assignment procedure are described elsewhere in [5]. The studied microplastics were mainly light polyolefins (polyethylene, PE and polypropylene, PP) but one that was found to be composed mainly of cellulose. Other compounds and additives associated with the microplastics, such as fatty acids, ketones and plasticizers (phthalates) were found with discriminant value to differentiate different polymers. Py-GC/MS was found an appropriate tool for microplastic research. In this work it was possible to identify the nature of all samples studied, elucidate they polymer composition if any and also provide valuable information about origin and production line.

[1] Andrady, A.L. (2011). Microplastics in the marine environment. Mar. Pollut. Bull. 62: 1596―1605. [2] Rochman, C.M. (2018). Microplastics research—from sink to source. Science 360 (6384): 28―29. [3] Herrera, A., Asensio, M., Martínez, I., Santana, A., Packard, T., & Gómez, M. (2018). Microplastic and tar pollution on three Canary Islands beaches: an annual study. Mar. Pollut . Bull. 129: 494―502. [4] Anderson, J.C., Park, B.J., & Palace, V.P. (2016). Microplastics in aquatic environments: Implications for Canadian ecosystems. Environ. Pollut. 218: 269―280. [5] González-Pérez J.A., Jiménez-Morillo N.T., de La Rosa Arranz J.M., Almendros G., González-Vila F.J. (2015). Pyrolysis-gas chromatography-isotope ratio mass spectrometry of polyethylene. J. Chrom. A 1388: 236―243.

Layla M. San Emeterio ‘Ministerio de Ciencia, Innovación y Universidades’ grant BES-2017-079811. Projects CGL2016-78937-R co-financed by FEDER Funds. Desiré Monis and Alba Carmona for technical assistance.

Póster (P-EA-22) presentado en la XVIII Reunión de la Sociedad Española de Cromatografía y Técnicas Afines (SECyTA 2018), Granada, del 2 al 4 de Octubre de 2018.

Peer reviewed