BANGKOK: Thailand's capital was covered in smog on Monday (Sep 30), placing Bangkok's air quality among the most polluted globally.
As at 9.45am local time, air pollution in the city was ranked third in the world, the Bangkok Post reported, citing data from monitoring site IQAir AirVisual.
A total of 33 areas in Bangkok breached the safety threshold with PM2.5 readings above 50, local news site Khaosod also reported, citing the Pollution Control Department.
The worst PM 2.5 reading was recorded in Bangkok's Bang Kholaem district, with a figure of 78 microgrammes per cubic metre of air in the past 24 hours.
The neighbouring provices of Nonthaburi, Pathum Thani, Samut Prakan, Samut Sakhon and Nakhon Pathom were reportedly also shrouded in toxic dust.
The department’s director-general Pralong Damrongchai said the poor air quality was caused by winds and high humidity amid changing seasons.
Meanwhile, Prime Minister Prayut Chan-Ocha has advised people to wear masks outdoors.
Posting on social media, the premier appealed to factories and construction sites to reduce their smoke and dust emissions.
Industrial emissions, construction, crop burning and vehicle fumes have caused pollution levels to spike in Thailand in recent years.
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The region has suffered from poor air quality caused by Indonesian forest fires in the past few weeks.
Hazy conditions eased in the last week, after rain in parts of Indonesia's Sumatra and Kalimantan brought down the number of hotspots.