Relative recent evidence has shown that the southward flowing Canary Current is leaving on the Canary Islands important amounts of marine debris, specially plastic, from the open North Atlantic Ocean, mainly on North and Northeast exposed beaches [1-3]. However, up to the development of this study by the end of 2018, no works had focused on the study of the presence of microplastics in beaches of the occidental islands (Tenerife, La Palma, La Gomera and El Hierro), which is highly necessary in order to fully evaluate their content, distribution and also the possible detection of “hot spots” or “black points” with an extremely high content of microplastics. In this work, the occurrence and composition of microplastics (1-5 mm) was evaluated in six beaches of the island of Tenerife for the first time [4]. Two of them were located at the North coast (El Socorro and San Marcos) and the rest in the South littoral (Leocadio Machado, El Porís, Los Abriguitos and Playa Grande). Sampling was developed during the months of October, November and December 2018 (depending on the beach). Isolated microplastics were identified by attenuated total reflection Fourier transform infrared spectroscopy. All beaches showed a relatively low content of microplastics, except Playa Grande, which showed an average content of 98.97 g/m2. The major polymers found were polyethylene, polypropylene and polystyrene, accounting for 69 %, 18 % and 4 %, respectively. References [1] A. Herrera et al., Mar. Pollut. Bull., 2018, 129, 494–502. [2] C. Edo et al., Mar. Pollut. Bull., 2019, 143, 220–227. [3] J. Baztan et al., Mar. Pollut. Bull., 2014, 80, 302–311. [4] C. Álvarez-Hernández et al., Mar. Pollut. Bull., 2019, 146, 26–32.