Background
The Mediterranean Sea is almost completely enclosed, bordered by the coastlines of 23 countries in Southern Europe, Northern Africa and Asia. From the Strait of Gibraltar on the West, a 14 km-wide opening towards the Atlantic Ocean, to the mouth of the Dardanelles (a 1.2 to 6 km-wide opening towards the Black Sea) and the Suez Canal (a 365 m-wide opening towards the Red Sea), the Mediterranean extends over more than 2.5 million square kilometres.
Due to its tightly enclosed geographical situation, the intensity of maritime transport and fishing, as well as industrial and tourist activities, the Mediterranean Sea is particularly sensitive to plastic pollution. Directly thrown into the sea or drained by river waters, plastic waste accumulates and breaks up into pieces that can no longer be recovered. The Mediterranean Sea therefore harbours between 1 and 10 million plastic particles per square kilometre, i.e. between 5 and 10% of the global plastic mass [4] . The sixth largest global accumulation zone after the 5 Ocean gyres*, it is considered to be the most polluted sea in the world [8].
Legislation
To combat the plastic scourge, some countries in the Mediterranean region have already implemented regulations. For example, single-use plastic bags have been banned in France, Italy, Morocco and Tunisia, have to be paid for in Cyprus and Turkey, whilst there is an eco-tax for them in Malta and Greece [9].
In 2018, the European Commission adopted the first European strategy for plastic products, which forms part of the transition towards a circular economy**. The aims of this strategy are: to reduce consumption of single-use plastic, to increase recycling and to limit the intentional use of micro plastics. Furthermore, this strategy encourages European Union members to aim for 55% of all household waste to be recycled by 2025 and 65% by 2030. Member states must also be capable of recycling all plastic packaging by 2030.
However, despite the existence of regional action plans, legally binding measures and the common will of all the countries concerned to combat plastic pollution, its reduction is made difficult due to the heterogeneity of the demographic, economic and geopolitical situations of the coastal countries.
*The five ocean gyres are found in the middle of the North Atlantic, the South Atlantic, the Indian Ocean, the South Pacific and the North Pacific. They are huge rotating ocean currents resulting from the convergence of marine currents. Under the action of a significant centripetal force, waste accumulates in their centre.
**The circular economy refers to an economic model whose objective is to produce goods sustainably, based on the re-use of used products. Consequently, raw materials are extracted once only, then transformed into a product that is consumed after which it is reused or recycled. It is in contrast to the linear economy whose model is to extract, transform, consume and discard.