Smog Surges Over Thailand’s Two Major Cities

Smog over Bangkok Jan. 15.
Smog over Bangkok Jan. 15.

BANGKOK — Thailand featured two of the world’s most-polluted cities Wednesday morning, according to independent – not government – monitoring.

Chiang Mai and Bangkok ranked seventh and ninth respectively in a list of polluted urban centers, according to data from AirVisual. The capital’s air quality was indexed at 166, while Chiang Mai’s was 180, both of which are considered “unhealthy.”

However, the official government source of air quality information still offered a much rosier assessment. According to the Pollution Control Department’s Air4Thai app, most of Bangkok was shown to be only moderately polluted.

“Air4Thai is not real-time. The reported results are four hours behind. The reporting system needs to change,” said Tara Buakamsri, director of Greenpeace Thailand. “We’ve all had to rely on other apps, which are real time.”


Tara said the air in both cities was unhealthy. Exercising outdoors and opening windows is discouraged and the use of masks and air filters is strongly recommended.

Tara said the smog is expected to lay stagnant over the cities for the next couple of days, since there is little wind to flush it out over the Gulf of Thailand.

“Many spots in Bangkok will cage in the smog as well, especially between tall condos as big as malls. Even if the air quality is good in Bangkok on many days, some spots will continue to hold in dust,” he said.

Thai cities have been on alert since January for high levels of PM2.5 particles – the smallest and most harmful type – while the government has continued to field discredited solutions such as spraying water into the air.

Schools were closed for several days at the end of January and the public has scrambled to purchase masks.

Smog in Chiang Mai, known for its unclean air, is caused by both transportation emissions and slash-and-burn farming.

Related stories:

As Bangkok Clears, Provinces Choke on Seasonal Smoke

Bangkok Schools Ordered Closed Due to Smog

‘I Don’t Know What to Do’ About Smog: Bangkok Governor

Bangkok’s Air More Toxic Than You Think: Greenpeace

Worsening Smog Spreads Across Metropolitan Bangkok

Rail Construction Halted, Drivers Fined as Smog Persists


Bangkok Pollution Has Always Been Bad – So Have the Solutions: Experts

Burning Sugarcane Stalks Contributes to Smog: Activists

Chiang Mai Has Worst Small Particle Pollution in Thailand: Greenpeace