The leaders of Thailand and its neighboring Myanmar and Laos held video talks to discuss the problem of transboundary haze pollution on Friday. In recent weeks, smoke from forest fires and farmers burning crop stubble has blanketed the northern Thai city of Chiang Mai and the central area bordering Myanmar. The fine particulate matter, PM2.5 dust particles, has affected 1.32 million people nationwide, causing respiratory diseases, skin and eye infections.