Smoky haze from Laos raised PM2.5 levels sharply in the Northeast with the fine dust exceeding safe limits in 34 provinces, according to the Pollution Control Department.
Attapon Charoenchansa, director-general of the department, said inbound smoke from the neighboring country was affecting Issan.
Air quality will be good in greater Bangkok and moderate in the North during the Songkran festival, but particulate matter 2.5 micrometers and less in diameter may thicken on April 18 and 19 when air is expected to be stagnant.
Attapon said Tuesday’s PM2.5 was at unsafe levels in 34 provinces including Bangkok.
According to data from the IQAir, website which ranks worldwide air quality, PM2.5 in Bangkok was the fifth worst with its air quality index at 156, which indicated health hazard to everyone.
The website also reported that PM2.5 concentration in Bangkok was 13 times as much as the standard of the World Health Organization.