Assessment of marine debris on the Belgian Continental Shelf Lisbeth Van Cauwenberghe a,⇑ , Michiel Claessens a,1 , Michiel B. Vandegehuchte a , Jan Mees b,c , Colin R. Janssen a a Ghent University, Laboratory of Environmental Toxicology and Aquatic Ecology, Jozef Plateaustraat 22, 9000 Ghent, Belgium b Flanders Marine Institute (VLIZ), Wandelaarkaai 7, 8400 Oostende, Belgium c Biology Department, Marine Biology Research Group, Ghent University, Krijgslaan 281/S8, 9000 Ghent, Belgium article info Keywords: Marine debris Southern North Sea Abundance Composition Plastics Microplastics abstract A comprehensive assessment of marine litter in three environmental compartments of Belgian coastal waters was performed. Abundance, weight and composition of marine debris, including microplastics, was assessed by performing beach, sea surface and seafloor monitoring campaigns during two consecu- tive years. Plastic items were the dominant type of macrodebris recorded: over 95% of debris present in the three sampled marine compartments were plastic. In general, concentrations of macrodebris were quite high. Especially the number of beached debris reached very high levels: on average 6429 ± 6767 items per 100 m were recorded. Microplastic concentrations were determined to assess overall abun- dance in the different marine compartments of the Belgian Continental Shelf. In terms of weight, mac- rodebris still dominates the pollution of beaches, but in the water column and in the seafloor microplastics appear to be of higher importance: here, microplastic weight is approximately 100 times and 400 times higher, respectively, than macrodebris weight. Ó 2013 Elsevier Ltd. All rights reserved. 1. Introduction Our seas and oceans are subjected to different kinds of threats of which the accumulation of anthropogenic debris is a major and worldwide problem. Although the origin of these polluting materials is both land- and waterway-related, land-based sources are considered to be more significant since they account for over half of the world’s marine debris (GESAMP, 1991; Sheavly, 2007). Despite widespread recognition of the problem, evidence suggests that debris pollution is still increasing (Barnes et al., 2009; Moore, 2008; Ryan et al., 2009). As marine debris is quite variable in type so are its environmen- tal and economic implications. It is aesthetically displeasing, mak- ing shorelines unattractive and forcing coastal communities to invest in beach maintenance. It can also be a nuisance to boaters and the shipping industry, and result in damage to vessels and equipment (McIlgorm et al., 2011). The deleterious effects most widely reported are those imposed on marine biota (Derraik, 2002; Laist, 1997). Marine organisms can be entangled in nets, fishing line, ropes and other debris, which can inflict cuts and wounds or cause suffocation or drowning. Ingestion of marine lit- ter may cause obstructions in throats or digestive tracts. Finally, marine litter can also pose a threat to human health and safety, as beach visitors can be harmed by broken glass, medical waste and syringes (Sheavly and Register, 2007). Decades ago, most of our waste was composed of organic, degradable materials. Now, our solid wastes often contain syn- thetic elements, plastics in particular. Plastics have a range of un- ique properties, making them popular for use in everyday life: they can be used at a very wide range of temperatures, provide an excellent oxygen/moisture barrier, are bio-inert, strong and though but lightweight at the same time, durable, and above all, they are cheap (Andrady, 2011; Andrady and Neal, 2009; Laist, 1987). However, some of these characteristics (durability, strength, light weight, etc.) are properties that make plastics a serious envi- ronmental contaminant (Pruter, 1987). Approximately 58 million tons of plastic are produced annually in Europe; globally annual production increases to 280 million tons per year (PlasticsEurope, 2012). Despite the magnitude of this potential problem, little quantitative information is available on the quantity of plastics that eventually ends up in the marine environment, although it is estimated that up to 10% of all newly produced plastics will eventually find their way to our seas and oceans (Thompson, 2006). This would mean that presently approximately 28 million tons of plastics per year end up in the marine environment. Plastics account for the major part of marine litter and it has been esti- mated that plastics contribute from 60% to 80% of the total marine debris (Gregory and Ryan, 1997). Other types of debris found in considerable quantities in the marine environment are glass and 0025-326X/$ - see front matter Ó 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.marpolbul.2013.05.026 ⇑ Corresponding author. Tel.: +32 9 264 37 07; fax: +32 9 264 37 66. E-mail address: lisbeth.vancauwenberghe@UGent.be (L. Van Cauwenberghe). 1 Present address: DuPont Coordination Center, Antoon Spinoystraat 6, 2800 Mechelen, Belgium. Marine Pollution Bulletin xxx (2013) xxx–xxx Contents lists available at SciVerse ScienceDirect Marine Pollution Bulletin journal homepage: www.elsevier.com/locate/marpolbul Please cite this article in press as: Van Cauwenberghe, L., et al. Assessment of marine debris on the Belgian Continental Shelf. Mar. Pollut. Bull. (2013), http://dx.doi.org/10.1016/j.marpolbul.2013.05.026