BANGKOK – Ultrafine dust blanketed much of Thailand on Monday, with unsafe levels of PM2.5 pollution recorded in Bangkok and 45 provinces over the past 24 hours, according to data released by the Geo-Informatics and Space Technology Development Agency (Gistda). The readings highlight a severe and persistent air quality crisis affecting the Central Plains, Northeast, and North regions of the country.

Bangkok Gripped by Severe PM2.5 Pollution, Health Warnings Issued

As of 8 a.m., PM2.5 concentrations—fine particulate matter measuring 2.5 micrometres or less in diameter—ranged from 39.4 to 60.7 microgrammes per cubic metre (µg/m³), far exceeding the government’s safe threshold of 37.5 µg/m³. The highest level was recorded in Samut Sakhon, west of Bangkok, at 60.7 µg/m³.

In the capital, the average PM2.5 concentration rose to 53.6 µg/m³, up from 49.1 the previous afternoon, with all 50 districts reporting unhealthy air. Nong Khaem district remained the most affected area in Bangkok, with levels climbing to 59.4 µg/m³. Other provinces with critically high pollution included Samut Songkhram, Nong Khai, Nonthaburi, and Nakhon Pathom.

Ultrafine dust was at unsafe levels in Bangkok and 45 provinces over the past 24 hours, as of Monday morning, according to the Geo-Informatics and Space Technology Development Agency (Gistda).

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In contrast, only eight provinces—primarily in the far south and north—enjoyed good air quality, with PM2.5 levels between 16 and 24.9 µg/m³. These were Mae Hong Son, Chiang Mai, Satun, Songkhla, Phuket, Nakhon Si Thammarat, Narathiwat, and Lampang. A number of other provinces reported moderate air quality.

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The Meteorological Department warned that poor air ventilation is expected to persist on Monday, Tuesday, and Sunday, likely trapping pollutants close to the ground. A brief respite is forecast from Wednesday to Saturday as a high-pressure system is expected to bring stronger winds and improved dispersion conditions. Health authorities continue to advise vulnerable groups to limit outdoor exposure and wear protective masks.

-Thailand News (TN)