KOH LARN, Chonburi — An oily substance resembling engine oil washed up along more than one kilometre of beach on the western side of Koh Larn on Sunday afternoon, leaving tourists covered in the sticky residue after swimming.
Around midday on August 9th, 2026, beach umbrella operators and speedboat operators reported and photographed a strange film-like substance floating in the sea. Waves pushed the material ashore along Tien Beach and Samae San Beach in Village 7.
Photos showed large patches of the oily film being carried onto the sand, where it formed small clumps stretching continuously for more than a kilometre along the western coastline of the island.
Tourists who had been swimming emerged from the water with the substance smeared across their bodies and hurriedly washed it off. There have been no reports so far of anyone suffering allergic reactions or other health effects from contact with the material.
Pattaya City Mayor Poramese Ngamphichet told local news reporters that officials from the city clerk’s office are being sent to the site to investigate. Authorities expect to determine the nature of the substance and its origin.
