During this time, many provinces in the northern region are still facing smog and toxic dust. including smog from burning in the area In addition, there is also smog that burns in neighboring countries being blown across the border by the wind. making the western side of the northern region both Mae Hong Son and Chiang Mai Filled with dense smog Hourly levels of toxic dust in some areas are higher than 700 micrograms per cubic meter. And Chiang Mai Mai still periodically ranks among the world's most polluted cities. Source: Thai News Agency