Enhancing the determination of European Union Watch List Organic pollutants adsorbed on microplastic debris by single-step ultrasound-assisted extraction coupled with ultra-high performance liquid chromatography tandem mass spectrometry

• Microplastics (MPs) can adsorb and transport organic pollutants. • Twenty-five emerging organic pollutants from the EU Watch list were studied. • The UAE-(UHPLC-MS/MS) method presents high efficiency and precision. • The method was applied for monitoring the presence of target analytes in microplastic debris samples. • The presence of various micropollutants was observed. Microplastics (MPs) have become a concerning environmental issue for their ubiquity and potential to adsorb organic pollutants, and for posing risks for ecosystems and human health. This study presents an effective optimised method to determine the variability of the concentrations of 25 emerging organic pollutants from the latest EU Watch List adsorbed on MP debris. The method involves a single-step ultrasound-assisted extraction (UAE), followed by ultrahigh-performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS), for their determination, which results in enhanced efficiency and precision in pollutants identification. By this approach, the linearity for all the analysed compounds exhibited correlation coefficients (r 2 ) over 0.990, with limits of detection (LOD) and limits of quantification (LOQ) ranging from 0.03 to 8.55 ng/g and 0.07 to 28.50 ng/g, respectively. The mean recovery of 71–106 % was achieved and relative standard deviations (RSDs) were less than 15 %. Subsequently, the method was applied to screen for the target analytes in the MPs debris samples collected from many sandy beaches on the Tenerife Island (Canary Islands, Spain). The results indicated the presence of the selected micropollutants at concentrations ranging from 15 to 824 ng/g, with the highest concentrations for UV filter octocrylene, which was present in 83.3 % of the analysed samples. The proposed method offers a streamlined environment-friendly approach for adsorbed pollutants extraction from stranded MP debris, which emphasises its significance as a potential source of pollution in various environments.