Plastic waste dominates seafloor litter in Mediterranean and Black Sea surveys

Source: Science for Environment Policy

Researchers have trawled coastal areas of the Eastern Mediterranean and Black Sea for waste and found up to 1211 items of litter per km2. Plastic bags and bottles were some of the most commonly found items. They present the results in a recent study, which they say supports Marine Strategy Framework Directive (MSFD) implementation, as well as efforts to discourage plastic carrier bag use.

Marine litter has a range of damaging impacts. For instance, marine creatures can become entangled in floating nets or eat the litter. Floating litter can also transport non-native species into new environments and tiny plastic fragments, ‘microplastics’, have been shown to be long-term sources of pollutants, such as phthalates.

This study, conducted under the EU PERSEUS project1, assessed marine litter on the seafloor of five areas in the Eastern Mediterranean and the Black Sea — three gulfs in Greece, one gulf in Cyprus and one bay in Romania.

The researchers say this study highlights the need for action to tackle marine litter and is relevant to ‘descriptor 10’ of the MSFD. This is one of eleven qualitative criteria describing ‘good environmental status’ listed by the Directive and states that ‘Properties and quantities of marine litter do not cause harm to the coastal and marine environment‘. An important first step in satisfying this descriptor is to quantify marine litter. There is only limited information on quantities in the Mediterranean and Black Sea, however.

The study trawled the seabeds of the five areas for litter at a total of 94 sampling stations in early 2013. The researchers point out that rocky areas cannot be trawled, and that they focused on fishing grounds with sandy or muddy floors.

In total, 5398 items of marine litter were collected. The majority (3269) came from the Saronikos Gulf near Athens, where 1211 items were gathered per km2 of area trawled. The Limassol Gulf in Cyprus was the cleanest area, with 46 items collected and a litter density of 24 items/km2.

In all areas except the Constanta Bay in Romania, the majority of items were made of plastic. Nearly all (95%) items from the Saronikos Gulf were plastic, which exceeds the global average of 75%. Between 60-67% of finds in the Limassol Gulf, the Gulf of Patras and the Echinades Gulf were plastic. The figure was 45% in the Constanta Bay.

Half of all plastic items (49.6%) were bags. This result provides further support for the EU decision to reduce the use of plastic bags, the study says. Bottles accounted for 17.5% of plastic waste and sheets 13.5%. Fishing debris, such as lines and nets, contributed 6.7% of all plastic litter. After plastic, metals were the most common material, at 8.7%–22%, depending on the area, of items found. Glass and ceramics accounted for 6–22% of litter.

In all areas, over half (50.8–71.8%) of litter was between 5 x 5 cm and 20 x 20 cm in size. Small items, under 5 x 5 cm, also made up a significant percentage of litter, with ranges between 7% and 23%. Small fragments are a particular concern because they are difficult to remove from the sea, and are more likely to be ingested by animals or to transfer pollutants.

1. PERSEUS (Policy-oriented marine Environmental Research for the Southern European Seas) is supported by the European Commission under the Seventh Framework Programme. See:

Source: Ioakeimidis, C., Zeri, C., Kaberi, H. et al. (2014). A comparative study of marine litter on the seafloor of coastal areas in the Eastern Mediterranean and Black Seas. Marine Pollution Bulletin 89(1): 296–304. DOI:10.1016/j.marpolbul.2014.09.044.



Distribution and assessment of marine debris in the deep Tyrrhenian Sea (NW Mediterranean Sea, Italy)

Source: ScienceDirect

Authors: Michela Angiolillo, Bianca di Lorenzo, Alessio Farcomeni, Marzia Bo,
Giorgio Bavestrello, Giovanni Santangelo, Angelo Cau, Vincenza
Mastascusa, Alessandro Cau, Flavio Sacco, Simonepietro Canese


Marine debris is a recognized global ecological concern. Little is known about the extent of the problem in the Mediterranean Sea regarding litter distribution and its influence on deep rocky habitats. A quantitative assessment of debris present in the deep seafloor (30–300 m depth) was carried out in 26 areas off the coast of three Italian regions in the Tyrrhenian Sea, using a Remotely Operated Vehicle (ROV). The dominant type of debris (89%) was represented by fishing gears, mainly lines, while plastic objects were recorded only occasionally. Abundant quantities of gears were found on rocky banks in Sicily and Campania (0.09–0.12 debris m−2), proving intense fishing activity. Fifty-four percent of the recorded debris directly impacted benthic organisms, primarily gorgonians, followed by black corals and sponges. This work provides a first insight on the impact of marine debris in Mediterranean deep ecosystems and a valuable baseline for future comparisons.

Spatial pattern and weight of seabed marine litter in the northern and central Adriatic Sea

Source: ScienceDirect

Authors: P. Strafella, G. Fabi, A. Spagnolo, F. Grati, P. Polidori, E. Punzo, T. Fortibuoni, B. Marceta, S. Raicevich, I. Cvitkovic, M. Despalatovic, G. Scarcella


The present study analyzes spatial distribution and typology of marine litter on the seabed in the FAO Geographical Sub-Area 17 (northern and central Adriatic Sea). Two surveys were conducted during fall 2011 and 2012 and 67 stations were sampled each year. Litter items were collected using the “rapido” trawl, a modified beam trawl commonly used by the Italian fishermen to catch flat fish and other benthic species. Marine litter in the catches was sorted and classified in 6 major categories (plastic, metal, glass, rubber, wood, other). Plastic litter was further subdivided in 3 sub-categories based on its source: fishing nets, aquaculture nets and other. Plastic was dominant in terms of weight followed by metal and other categories. The highest concentration of litter was found close to the coast likely as a consequence of high coastal urbanization, river inflow and extensive navigation associated with the morphological and hydrological features of the basin.

Modelling the transport and accumulation of floating marine debris in the Mediterranean basin

Source: Science Direct

Authors: J. Mansui, , A. Molcard, Y. Ourmières


In the era of plastic and global environmental issues, when large garbage patches have been observed in the main oceanic basins, this work is the first attempt to explore the possibility that similar permanent accumulation structures may exist in the Mediterranean Sea. The questions addressed in this work are: can the general circulation, with its sub-basins scale gyres and mesoscale instabilities, foster the concentration of floating items in some regions? Where are the more likely coastal zones impacted from open ocean sources?

Multi-annual simulations of advected surface passive debris depict the Tyrrhenian Sea, the north-western Mediterranean sub-basin and the Gulf of Sirte as possible retention areas. The western Mediterranean coasts present very low coastal impact, while the coastal strip from Tunisia to Syria appears as the favourite destination. No permanent structure able to retain floating items in the long-term were found, as the basin circulation variability brings sufficient anomalies.


A comparative study of marine litter on the seafloor of coastal areas in the Eastern Mediterranean and Black Seas

Source: ScienceDirect

Authors: C. Ioakeimidis, C. Zeri, H. Kaberi, M. Galatchi, K. Antoniadis, N. Streftaris, F. Galgani, E. Papathanassiou, G. Papatheodorou


In the present work, abundance, spatial distribution and qualitative composition, of benthic marine litter, were investigated in five study areas from the Eastern Mediterranean and Black Seas (Saronikos, Patras and Echinades Gulfs; Limassol Gulf; Constanta Bay). Surveys were performed using the monitoring protocol proposed by the Technical Group for Marine Litter. Densities ranged from 24 items/km2 to 1211 items/km2, with the Saronikos Gulf being the most affected area. Plastics were predominant in all study areas ranging from 45.2% to 95%. Metals and Glass/Ceramics reached maximum values of 21.9% and of 22.4%. The size distribution of litter items showed that ⩾50% fall into medium size categories (10 × 10 cm, 20 × 20 cm) along with an elevated percentage of small-sized (<5 × 5 cm) plastic litter items. The comparative analysis of the data highlighted the dependence of the marine litter problem on many local factors (human sources and oceanographic conditions) and the urgent need for specific actions.

Levels and fate of perfluoroalkyl substances in beached plastic pellets and sediments collected from Greece

Source: Marine Pollution Bulletin

Authors: Marta Llorca, Marinella Farré, Hrissi K. Karapanagioti, Damià Barceló


Plastic debris damages marine wildlife and ecosystems becoming an important source of marine pollution. In addition, they can sorb, concentrate and stabilise contaminants acting as toxic carriers to the marine food web. In this context, the presence of 18 perfluoroalkyl substances (PFASs) in plastic pellets (n = 5) and beach sediment (n = 9) samples widely distributed around Greek coastal areas was assessed.

The results, mainly, showed the sorption of PFASs onto pellet surface from surrounding water with concentrations from method limit of quantification to 115 ng/kg for C5, C7, C8 and C10 carboxylic acids and C8 sulfonate acid. A similar pattern was found by comparing plastic pellets and sediment for the same sampling locations that could indicate a common origin of contamination in both types of samples. However, since the number of analysed samples is limited, a more comprehensive study with a higher number of samples should be performed in future research.

Floating debris in the Mediterranean Sea

Source: ScienceDirect

Authors: Giuseppe Suaria, Stefano Aliani


Results from the first large-scale survey of floating natural (NMD) and anthropogenic (AMD) debris (>2 cm) in the central and western part of the Mediterranean Sea are reported. Floating debris was found throughout the entire study area with densities ranging from 0 to 194.6 items/km2 and mean abundances of 24.9 AMD items/km2 and 6.9 NMD items/km2 across all surveyed locations. On the whole, 78% of all sighted objects were of anthropogenic origin, 95.6% of which were petrochemical derivatives (i.e. plastic and styrofoam). Maximum AMD densities (>52 items/km2) were found in the Adriatic Sea and in the Algerian basin, while the lowest densities (<6.3 items/km2) were observed in the Central Tyrrhenian and in the Sicilian Sea. All the other areas had mean densities ranging from 10.9 to 30.7 items/km2. According to our calculations, more than 62 million macro-litter items are currently floating on the surface of the whole Mediterranean basin.