Plastic accumulation in the Mediterranean sea

PLoS One. 2015 Apr 1;10(4):e0121762. doi: 10.1371/journal.pone.0121762. eCollection 2015.


Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Humans
  • Mediterranean Sea
  • Particle Size
  • Plastics / chemistry*
  • Waste Products
  • Water Pollution*


  • Plastics
  • Waste Products

Grant support

The present study was funded by the EU's Framework Programme 7 and the Spanish Ministry of Economy and Competitiveness through projects MedSeA (EU contract number FP7-2010-265103), ESTRESX (ref. CTM2012-32603) and MEGAN (ref. CTM2013-49048-C2-1-R). Andrés Cózar is grateful for the funding of a "Salvador de Madariaga" stay to continue the study of the plastic pollution in the Mediterranean Sea (Spanish Ministry of Education, Culture and Sport, ref. PRX14/00743). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.