It's visible in satellite images from just off Sri Lanka's coast: a thin grey film that snakes three kilometres out to sea before disappearing into the waves.
When a fire broke out on the deck of the M/V XPress Pearl cargo ship on May 20, 2021, an estimated 70-75 billion pellets of preproduction plastic material, known as nurdles, spilled into the ocean and along the Sri Lankan coastline. That spill of about 1,500 tons of nurdles, many of which were burnt by the fire, has threatened marine life and poses a complex clean-up challenge.