Over the last six decades, according to one estimate, 9.1 billion tons of plastic has been produced worldwide and 7 billion tons of it has ended up as waste. Much of that waste has infiltrated our oceans. And, according to another estimate, more than 8 million tons of plastic is dumped into the sea each year.
Researchers from the Helmholtz-Center for Environmental Research in Germany, think they’ve nailed down a crucial detail about plastic pollution: how it gets into the ocean. And, they found, just 10 rivers account for 90 percent of the plastics flowing into the seas. Their study is published in the journal Environmental Science & Technology.
The problem of our plastic-filled oceans has been studied for years, but until now there has been little information on how the plastic gets there. Christian Schmidt, a hydrogeologist at the center who led the study, believes that to get plastic out of the ocean, we must first figure out how it is getting in.
“For the ocean science community, it’s important to understand how plastic debris spreads in the oceans,” Schmidt told Seeker. “[Until now] it has been sufficient to know that 80 percent of ocean plastic is generated from land, but current research is more directed to the sources of the problem.”
Just 10 river systems are responsible for 90 percent of the plastic flowing into the oceans. Eight are in Asia and two are in Africa. Ranked from the highest amount of plastic waste to the lowest, they are: the Yangtze River, Indus River, Yellow River, Hai He River, Nile River, Ganges River, Pearl River, Amur River, Niger River, and the Mekong River.