Contents lists available at ScienceDirect Marine Pollution Bulletin journal homepage: www.elsevier.com/locate/marpolbul Microplastics in edible mussels from a southern Mediterranean lagoon: Preliminary results on seawater-mussel transfer and implications for environmental protection and seafood safety Takwa Wakkaf a,b , Radhouan El Zrelli a,c , Mikaël Kedzierski d , Rafik Balti b , Moez Shaiek e,f , Lamjed Mansour g , Sabiha Tlig-Zouari a , Stéphane Bruzaud d , Lotfi Rabaoui a, ⁎ a University of Tunis El Manar, Faculty of Science of Tunis, Laboratory of Biodiversity, Parasitology and Aquatic Ecosystems (LR18ES05), University Campus, 2092 Tunis, Tunisia b University of Jendouba, Higher Institute of Biotechnology of Béja, Research Unit of Functional Physiology and Bio-Resources Valorization (UR17ES27), Habib Bourguiba Avenue, Béja 9000, Tunisia c SADEF, 30 Rue de la Station, 68700 Aspach-Le-Bas, France d Université Bretagne Sud, IRDL, UMR CNRS 6027, Lorient, F-56100, France e Association Méditerranée Action Nature, 1 Rue d’Istanbul 7000 - Bizerte, Tunisia f Thetis-Conseil, 1 Rue d’Istanbul 7000- Bizerte, Tunisia g Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia ARTICLE INFO Keywords: Plastic pollution Mytilus galloprovincialis Filter-feeders Seawater Seafood Mediterranean Sea ABSTRACT This study assesses the microplastics (MPs) levels in mussels (Mytilus galloprovincialis) and seawater from a southern Mediterranean lagoon (Bizerte lagoon, Northern Tunisia) and discusses the potential effects of its consumption on human health. Polyethylene was the most abundant in mussels and seawater, followed by polypropylene and cellophane. The lowest and highest average MPs concentrations were recorded in the lagoon channel and southern area of the lagoon, respectively, for both mussels (2.6 ± 1.7–12.0 ± 1.4 items mussel -1 ) and seawater (0.2 ± 0.1–0.7 ± 0.2 items L -1 ). Mussels in areas highly polluted with fibers and polyethylene were found to have higher potential to ingest and/or adhere higher numbers of these particles. The annual dietary intake of MPs by Tunisians through the consumption of local mussels was estimated at 4.2 items ca- pita -1 year -1 . Even though MPs are not biodegraded and can be excreted by humans, their potential human health risks are discussed in this paper. 1. Introduction Plastic pollution in the marine environment has become along the past decade an emerging environmental issue that made the subject of hundreds of studies around the globe (e.g. Eriksen et al., 2014; Clunies- Ross et al., 2016; Arossa et al., 2019; Cincinelli et al., 2019; Kedzierski et al., 2019a). Indeed, the wide use of plastic in our modern life (clothing, food wrappers, computers, cars…) has exploded their pro- duction which went from 2 (1950) to 359 million metric tons in 2018 (Geyer et al., 2017; PlasticsEurope, 2019). Up to early 2000, the management of plastic wastes had not been considered as an environ- mental priority, leading therefore to the continuous enrichment of marine environment with these contaminants. The presence of plastic micro-particles (of a size ranging between 0.1 and 5000 μm), called microplastics (MPs), was reported in throughout the world's oceans from the shallow coastal areas to the deep oceanic trenches (Wright et al., 2013; Law and Thompson, 2014; Cole et al., 2014). Within this context, the Mediterranean Sea was reported to be one of the most impacted regions with regards to MPs, with the highest concentrations of floating plastics in the world (Lebreton et al., 2012; Eriksen et al., 2014; Suaria et al., 2016; Kedzierski et al., 2019a). Reaching such highest records was mainly driven by the limited outflow of surface waters, combined with the important urban development along the coasts and the related anthropogenic pressures such as fishing, ship- ping, touristic and industrial activities which generate thousands of tons of litter that end in the Mediterranean waters (Suaria et al., 2016). According to van Sebille et al. (2015), the Mediterranean Sea retain between 21% and 54% of plastic particles and between 5% and 10% of the global plastic mass, so that between 3.2 and 28.2 × 10 12 particles and between 4.8 and 30.3 thousand tonnes. https://doi.org/10.1016/j.marpolbul.2020.111355 Received 19 May 2020; Accepted 4 June 2020 ⁎ Corresponding author. E-mail address: lrabaoui@gmail.com (L. Rabaoui). Marine Pollution Bulletin 158 (2020) 111355 Available online 24 June 2020 0025-326X/ © 2020 Published by Elsevier Ltd. T