Diver and filmmaker Tahsin Ceylan swims to inspect the sea covered with a plague of sea snot, a thick slimy layer of the organic matter, also known as marine mucilage, spread through the Sea of Marmara and which poses a threat to marine life and the fishing industry, on the shores of Istanbul, Turkey June 8, 2021. REUTERS/Umit Bektas
The Sea of Marmara continues to be clogged up by slimy pollution. Reuters

Sea slime is not just Turkey's problem