Widespread smog blankets Ho Chi Minh City as air quality deteriorates

Despite bright sunshine, the city’s sky remained hazy, and numerous skyscrapers appeared shrouded in the mist. The widespread smog limited visibility on many central streets, with particularly dense patches affecting various areas.

According to the Southern Regional Hydro-Meteorological Center, the phenomenon was caused by a cold air mass moving southward, combined with high humidity levels near the ground.

Such occurrences have been frequent in the late months of the year and are expected to persist on several days leading up to the Lunar New Year.

The real-time air quality monitoring platform IQAir, headquartered in Switzerland, ranked Ho Chi Minh City as the world’s third most polluted city this morning, following Hanoi and Dhaka, Bangladesh. Between 6 a.m. and 11 a.m., air quality levels in the southern metroplis ranged from 197 to 201 on the Air Quality Index (AQI).

In some areas, pollution exceeded the “red” category and entered the “purple” zone (AQI 201–300), indicating very unhealthy air conditions that pose health risks to residents.

Specific locations reported alarming AQI readings, such as 262 at the Saigon Pearl International School in Binh Thanh District and 243 at the German International School in An Phu, Thu Duc City.

In An Phu, fine particulate matter (PM2.5) concentrations reached 168.2 µg/m³, 33.64 times higher than WHO’s annual air quality guideline of 5 µg/m³.

Even suburban areas like Long Binh Ward (Thu Duc City) and Hiep Phuoc Commune (Nha Be District) recorded AQI levels of 239 and 220, respectively.

Although pollution levels slightly decreased by noon as the sun intensified, most monitoring stations continued to report AQI readings in the “red” and “purple” zones, signaling hazardous air quality.