It breaks down into tiny particles eaten by plankton, which are then eaten by small fish, which are eaten by larger fish until they end up in the fish we eat.
Indeed, sea salt, beer, honey, sugar, tap water and the air we breathe all contain microscopic particles and a 2017 study showed we all have these tiny plastic particles in our bodies.
It would be impossible to dredge the plastic off the seabed; it is too deep and too melded to the marine life there but we can stop it getting worse.
“We have to stop plastic entering the oceans in the first place,” says Simon Bernard, 27, leader of the Plastic Odyssey project in Bordeaux, which is developing a converter to turn plastic into fuel and building materials.
The idea is to show it has a value and stop it being dumped. “We’re building a boat with the machines to travel the world like a floating laboratory, showing people how to build similar machines to turn waste into valuable commodities.
“Then plastic won’t end up in the sea.”
He and a team of volunteer techies and engineers have built a quarter-size prototype, called Ulysse, and are making the plans patent-free and open-source so they are free for others to use.
Mr Bernard said: “It is providing data to improve the design of Odyssey. We are now looking for technical partners and finance, to help build it, and for partners around the world, especially in the worst hit countries, to publicise the project and prepare for our arrival.
“It’s never too late. It would have been better if we had stopped before, but we can still stop polluting the oceans now.”
As a former merchant seaman he saw damage round the world and says while the government can take small steps and ban plastic straws it is a global problem.
“Plastic which enters the sea in France can end up anywhere in the world.”
Collecting plastic off the beach, they feed it into a shredder to make plastic chips which are fed into a small pyrolysis chamber at 450C to create an oil that is ‘cracked’ into petrol and diesel to drive the boat motor and other systems.
Odyssey will be powered by waste plastic on its global trip and although it is a daunting task, he is optimistic.
“The further we go, the more support we get. People are joining us, offering time and expertise for free. We feel like we’re going with the flow not against it.
“Lots of people contact us from Africa, as they want to do something, to join in, get the machines themselves.”
Plastic Odyssey’s voyage will show how to create energy from waste and their designs will be available for free.
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