Most Ocean Plastic May Come From Only 10 Rivers

Researchers may have come one step closer to identifying the ocean-plastic supply chain, as it seems most ocean plastic may come from only 10 rivers

Ocean plastic is a major problem worldwide, threatening marine life in a multitude of ways. In fact, as much as 8 million metric tons of plastic reaches the oceans every year. But now a new study by the American Chemical Society shows that as much as 4 million metric tons is carried to the sea by rivers.

Rivers and plastic

Here at Scuba Diver Life, we’ve already reported on a 2015 study, which found that five countries in the world are responsible for as much as 60 percent of all ocean plastic. These countries are China, Indonesia, Vietnam, Thailand and the Philippines. This was an important breakthrough in the understanding of where the plastic in our oceans comes from.

Now, research indicates that we can perhaps narrow down this focus even further. It seems that as much as 95 percent of the plastic in our oceans that arrives via rivers (4 million metric tons, as mentioned above) is carried there by only 10 rivers worldwide. Not surprisingly, given the countries mentioned above, eight of these rivers are found in Asia. China came in at first place in the 2015 study, and unsurprisingly, the Yangtze River was the No. 1 river contributing to the oceans’ plastic problem. Eight of the rivers are in Asia, and the full list includes:

  • Yangtze River, Yellow Sea, Asia
  • Indus River, Arabian Sea, Asia
  • Yellow River (Huang He), Yellow Sea, Asia
  • Hai River, Yellow Sea, Asia
  • Nile, Mediterranean Sea, Africa
  • Meghna/Bramaputra/Ganges, Bay of Bengal, Asia
  • Pearl River (Zhujiang), South China Sea, Asia
  • Amur River (Heilong Jiang), Sea of Okhotsk, Asia
  • Niger River, Gulf of Guinea, Africa
  • Mekong River, South China Sea, Asia

However, the problem doesn’t just exist in Asia. In the 2015 study, the U.S. came in at 20th place when it comes to ocean-plastic debris. That rivers are a major contributor to ocean plastic isn’t surprising, as we’ve long known that ocean plastic doesn’t just come from careless disposal of plastic near the coast. We know that plastic makes its way from far inland to the sea, carried by waterways such as rivers and streams. But until now it was unclear just how much.

Stemming the flow of ocean plastic

The American Chemical Society study helps illuminate the supply chain of ocean plastic, which will potentially make it easier to create measurements allowing us to stem the flow. Following the 2015 study, Indonesia pledged to help combat its role as a contributor to ocean plastic. The more we know, the easier it will be to pressure local governments around the world to make changes. Knowing the role of rivers — specifically which rivers — are the biggest polluters, can help these governments create programs where the efforts will have the greatest effect.

What can you do?

Many scuba divers are deeply concerned for the state of the oceans, and for good reason. We see firsthand the damage that is being done. So what can we as divers do?

First and foremost, eliminate plastic from your life as much as possible, especially the disposable kind. Plastic straws are a perhaps surprisingly big problem, so stop using them. Plastic bags are a problem, too, so choose a reusable shopping bag instead. And choose rags, sponges, and personal hygiene products that don’t contain micro-plastic. And of course, when you dive, remove any plastic and other polluting elements if you can do so safely.