Organic pollutants in microplastics from two beaches of the Portuguese coast J.P.G.L. Frias a,⇑ , P. Sobral a , A.M. Ferreira b a IMAR – Instituto do Mar, Departamento de Ciências e Engenharia do Ambiente, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, 2829-516 Monte de Caparica, Portugal b IPIMAR – INRB, Instituto Nacional dos Recursos Biológicos, Avenida de Brasília, 1449-006 Lisboa, Portugal article info Keywords: Microplastics PAHs PCBs DDTs Plastic pellets Portugal abstract Microplastics pose a threat to coastal environments due to their capacity to adsorb persistent organic pol- lutants (POPs). These particles (less than 5 mm in size) are potentially dangerous to marine species due to magnification risk over the food chain. Samples were collected from two Portuguese beaches and sorted in four classes to relate the adsorption capacity of pollutants with color and age. Polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and DDTs were analysed on pellets through gas chromatography mass spectrometry (GC-MS), and types of plastic were identified using Fourier trans- formed infra-red spectroscopy (micro-FTIR). Microplastics were mostly polyethylene and polypropylene. Regarding sizes, some fibres ranged from 1 to 5 lm in diameter and were 500 lm in length. The majority of samples collected had sizes above 200 lm. Black pellets, unlike aged pellets, had the highest concen- trations of POPs except for PAHs in Fonte da Telha beach. PAHs with higher concentrations were pyrene, phenantrene, chrysene and fluoranthene. Higher concentrations of PCBs were found for congeners 18, 31, 138 and 187. Further investigation is necessary to understand the relationship between plastic degrada- tion and adsorption for different pollutants. Ó 2010 Elsevier Ltd. All rights reserved. 1. Introduction Marine debris have become a pervasive pollution problem affecting all of the world’s oceans, being direct cause of injuries and death to marine animals and birds, either because they be- come entangled in drift nets and other debris or mistake plastic for food (Allsopp et al., 2006). Fauna close to case study beaches may be affected after ingesting marine debris, especially micro- plastics, as some studies suggest (Cadée, 2002; Vlieststra and Par- ga, 2002; Endo et al., 2005). Plastic fragments on beaches are derived either (1) from inland sources and are transported to coasts by water courses, wind, drainage systems or human activity, or (2) directly from the oceans where low density floating varieties accumulate and are trans- ported across great distances. Floating plastic fragments in the world’s oceans have been reported since the early 1970’s with the amount of debris showing a documented exponential increase into the early 1990’s (Corcoran et al., 2009). Lightweight plastics also reach the ocean from inland urban areas via storm drain sys- tems leading to rivers and the sea. Storms are the main source of transport from inland industries and cities directly to water courses, rivers and seas (Allsopp et al., 2006). The characteristics that make plastic materials so useful are the same that are prejudicial to the environment (high persistence, resistance to corrosion, low electric and thermal conduction) (Bockhorn et al., 1999). Broken or discarded fishing gear, pellets, scrubbers, microplastics, films and flakes are the most common plastic debris on beaches and at sea (Carpenter and Smith, 1972; Colton et al., 1974; Moore et al., 2001; Derraik, 2002; Thompson et al., 2004). Plastics can be found worldwide in coastal areas, and due to environmental dynamics they can attain small sizes (Moore, 2008). Plastic resin pellets and fragments of plastic resulting from breakdown of larger objects are known sources and sinks of xenoestrogens and persistent organic pollutants (POPs) in marine and aquatic environments (Moore et al., 2005; Mato et al., 2001) and can be readily ingested by invertebrates at the base of the food web (Thompson et al., 2004). Polyethylene and polypropylene, for instance, are widely employed as packaging media and constitute the main components of plastic waste from domestic refuse (Bock- horn et al., 1999). By adsorbing hydrophobic substances such as polycyclic aro- matic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), microplastics pose a higher environmental risk to marine organ- isms and though this subject has not been addressed consistently, it is likely that the whole food chain is affected due to the presence of plastics in all sizes and all depths in the ocean. Thus, the phys- ical, chemical and biologic components of the ecosystem may be 0025-326X/$ - see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.marpolbul.2010.07.030 ⇑ Corresponding author. Tel.: + 351 96 67 85 912. E-mail address: jpfrias@fct.unl.pt (J.P.G.L. Frias). Marine Pollution Bulletin 60 (2010) 1988–1992 Contents lists available at ScienceDirect Marine Pollution Bulletin journal homepage: www.elsevier.com/locate/marpolbul