Hanoi became the world’s most polluted city according to a ranking by IQ AirVisual on June 7.

The air quality index (AQI) ranking by Air Visual displayed 193 for Hanoi at 11.30 pm on June 7. Indonesia's Jakarta followed with AQI at 158.

On Pamair Application, some areas in Hanoi were marked with red and purple which meant that air quality was bad and very bad. For example, some areas with purple mark (very bad) included Ba Trieu Street in Hai Ba Trung District with AQI Index of 224; Vinh Hung in Hoang Mai District with AQI 222; and Dai La in Hai Ba Trung District with AQI 217.

Some other areas with a red mark (bad) included Doi Can Street in Ba Dinh District; Thuong Dinh in Thanh Xuan District; Cau Dien in Nam Tu Liem District; and Hoang Cau in Dong Da District.

According to Air Visual, the air quality index over 100 is considered bad and people with respiratory and heart diseases are advised to stay home. If the index increases to over 150, all citizens are affected.

Hanoi is being hit with an extreme hot spell with temperatures reaching to 37 degrees centigrade on June 7.

According to the National Centre for Hydro-Meteorological Forecasting, the hot spell would last until next Friday with a top temperature of 39 degrees centigrade. Tien Phong/Dtinews

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