"Bangkok's smog crisis forces 437 schools to close after governor warns 'children might be harmed'", 30 January 2019

More than 400 schools in Bangkok were ordered to close...as the Thai capital's air pollution intensified. Officials said the pollution exceeded acceptable levels in 39 separate areas and the city's governor, Aswin Kwanmuang, warned "children might be harmed".

Concentration of harmful fine particles known as PM2.5 increased at the end of December and has since remained above the World Health Organisation's safe threshold of 50 microgrammes per cubic metre.

..."[I]t will get worse as a result of El Nino that will take place very soon," says Tara Buakamsri, Thailand country director for Greenpeace Southeast Asia.

..."PM2.5 is hazardous to human health," says Somnuck Jongmeewasin, a lecturer on environment at the Thai Silpakorn University. "It causes acute and chronic effects to the respiratory and cardiovascular systems in the short and in the long run."

...According to the Pollution Control Department, as quoted by the Bangkok Post, the main reasons for the hazardous levels in the air are diesel-powered .

According to Witsanu Attavanich, an associate professor of Economics at the Kasetsart University, it is unlikely the government or industries will take the actions necessary to reduce air pollution because "it hurts the business".

"Economic benefit comes over the environment," he says.

However, there is some concern among the tourism and travel industry about the long-term effects of pollution.