Dangerous levels of arsenic in a northern Thai river contaminated by chemicals used in mines across the border in Myanmar risk unleashing an unprecedented ecological disaster on the kingdom’s waterways, environmentalists have warned, as images of the orange-yellow waters go viral. Bangkok is seeking renewed talks with Myanmar’s junta to stop the toxic sediment flowing downstream into the Kok River, which runs from Shan State, in Myanmar through Thailand’s border province of Chiang Rai. But the urgency of the health crisis for riverside communities – who have been warned not to wash, drink or eat fish from the contaminated waterway they depend on – is compounded by the fact that the mines are located in territory controlled by the Wa, an ethnic armed group notorious for drug production, unchecked resource extraction and opaque business ties to China. Thai villagers started to notice the discolouration of the water in March. However, satellite imagery suggests the contamination began as early as last September, when large upstream forest areas in Myanmar were cleared for mining – initially thought to be for gold, but now suspected to involve rare earths, based on the volume of chemical effluent released into the river. “The river has gone an awful colour, almost yellow-orange,” Penchom Saetang, founder of Earth (Ecological Alert and Recovery Thailand), told This Week in Asia after a visit to the site.

Full report : Authorities say arsenic levels in the Kok Thai river now exceed safety limits, sparking fears of ecological disaster.