Research suggests 3000 tonnes of the material is floating on the surface, with more added every year. And because the Sea is almost fully enclosed the plastic is trapped, taking decades to break down.
Not only are tourists swimming in the debris, marine creatures are mistaking it for food.
Scientists at the Society for the Protection of Turtles in Northern Cyprus are watching the plastic tide with alarm.
Postmortems on dead turtles have identified fragments inside their stomachs.
Robin Snape, project coordinator for the group, said: “In the green turtle it’s really common. The vast majority of them have some plastic in their gastro-intestinal tract. It’s more than 90%.”
The conservationists took us to a bay on the Karpaz Peninsula, close to one of the most important nesting beaches for the endangered green turtle.
We saw plastic packaging, straws and sheeting piled into large drifts along the high tide line.
Labels suggested some of the plastic had been swept by the wind and current from as far away as Turkey, Lebanon and North Africa.
Originally published on Sky News.