The invention of plastic and its gradual refinement were greeted with enthusiasm in the last century: an inexpensive, durable material with almost endless applications had been created. Yet, less than a hundred years later, plastic represents one of the greatest environmental catastrophes of our time. Every year, eight million tonnes of plastic are dumped into the planet's oceans; some waste can take decades to decompose, while other pieces crumble into tiny fragments known as microplastics, which are ingested by marine organisms and then work their way up the entire food chain until they reach our plates. The problem of plastic affects the entire planet, yet some areas are more polluted than others. A new study has revealed that of the 4 million tonnes of plastic transported by rivers to the sea each year, up to 95 per cent comes from just ten rivers.

Asia the worst offender

According to the study, conducted by a group of German researchers and published in the journal Environmental science & technology of the American chemical society, ten waterways alone are responsible for between 88 per cent and 95 per cent of all the plastic carried into the sea. Of these rivers, eight are located in Asia, confirming another study from 2015 which maintained that eleven of the twenty most plastic-polluted countries were on the Asian continent. According to the researchers, Asia is so vulnerable to this phenomenon because of its population density and inadequate waste management.

How to halve the waste

Despite the situation appearing compromised — at this rate, by 2050 there will be more plastic in the sea than fish — the authors of the study believe that better management of the ten most polluted waterways would be able to reduce by half the waste reaching the sea, eliminating roughly 45 per cent of it.

The 10 rivers responsible

While it is alarming that almost all of the plastic comes from such a small number of waterways, it will (would) on the other hand be easier to intervene. Here are the ten rivers that carry the most plastic in the world: the Yangtze river, which flows into the Yellow Sea, in Asia; the Indus river, Arabian Sea, Asia; the Yellow river, Yellow Sea, Asia; the Hai river, Yellow Sea, Asia; the Nile river, Mediterranean Sea, Africa; the Meghna/Brahmaputra/Ganges rivers, Bay of Bengal, Asia; the Pearl river, South China Sea, Asia; the Amur river, Sea of Okhotsk, Asia; the Niger river, Gulf of Guinea, Africa; and the Mekong river, South China Sea, Asia.

The role of fishing

The immense quantity of plastic floating in the Earth's waters — around 150 million tonnes, according to a statement by UN Secretary-General António Guterres — does not, however, come only from rivers. It is estimated that one fifth of the plastic is dumped into the sea by fishermen, ships and oil platforms.

The world's great rivers meet in Rome

A summit is due to take place in Rome in the coming days, from 23 to 25 October, bringing together for the first time the authorities responsible for the world's largest rivers. The aim of the summit, called I grandi fiumi del mondo si incontrano and organised by the Ministry of the Environment, is to find solutions to safeguard water resources, which are threatened by pollution and climate change.

Alliance of Italian businesses for water and climate

During the event — attended by the authorities responsible for managing the 47 principal water basins in the world, the municipalities bordering them, and major financial institutions — the Alleanza delle imprese italiane per l'acqua e il clima will be presented, with all of the country's most important companies having joined it. At the close of the summit, the managers of the water basins will sign a Dichiarazione di Roma, which will call for water to be included in the climate negotiations at COP23 in Bonn in November.

A shared fate

"We will bring together in Rome the representatives of all the world's great rivers to address the issues of climate change and how water scarcity in certain seasons and too much water in others causes 90 per cent of the world's environmental disasters," declared Environment Minister Gian Luca Galletti ahead of the meeting. "We will do so in a different spirit, knowing that either we all win together, or we all lose together. First and foremost, we must all agree on what to do and how to do it. The Rome Declaration on rivers will provide the main guidelines on how to act. The ethical and moral message is extremely powerful: either we start placing environmental policies as a priority for all countries, or climate events will drag us towards a worse and more dangerous world."