The Thai capital was behind only Mumbai in India (AQI 207) and Pakistan's Lahore (202). Chiang Mai ranked 13th with an AQI of 164.
Seventy air-quality monitoring stations across Bangkok registered unsafe levels of air pollution as of 7am, the Bangkok Air Quality Centre said.
PM2.5, the most dangerous air pollutant, soared above the safe limit of 50 micrograms per cubic metre of air (µg/m3) across the capital.
Thirty-eight stations detected “red” danger levels of PM2.5, above 90 µg/m3.
Fine PM2.5 dust particles can penetrate deep into the lungs and cause premature death from lung and heart conditions, especially among the elderly and those with health complications.
The 10 areas of Bangkok with highest PM2.5 levels on Thursday are:
The centre warned that air pollution will be high until Saturday (February 4) due to poor air circulation. It advised people in areas where smog is bad to avoid outdoor exercise and check the air quality before stepping outdoors.
PM2.5 levels are posted at bangkokairquality.com, the Bangkok Environment Department, Air Quality and Noise Management Division, the BMA Facebook page and the AirBKK smartphone app.
Bangkok’s air quality index on Thursday was higher than seven other world cities notorious for smog, namely Kuwait City (192 AQI), Karachi (189), Kabul (180), Chongqing (172), Delhi (172), Yangon (169), and Skopje (168).
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