Lahore continues to top the list of world's most polluted cities consecutively for the past few days, as its Air Quality Index (AQI) on Wednesday morning was recorded at the 'Hazardous' level of above 320.

According to IQAir, a Swiss air quality monitor, Lahore had the highest level of pollution in its air in the world on Wednesday also, which was categorised as ‘Hazardous’ with its air quality index measured at 323 in the morning.

The PM2.5 (particulate matter) concentration in the capital city of Punjab was recorded at 54.5 times higher than the WHO annual air quality guideline value.

PM2.5 refers to fine particulate matter with a diameter of less than 2.5 micrometers. The term is employed to characterize the levels of particles in both outdoor and indoor environments.

Also Read: Lahore, Karachi among top 3 most polluted cities in the world

Within Lahore, the most polluted areas were found to be The Mall road area with the highest AQI of 374, followed by the Lahore American School area and Polo Ground in Cantt.

The air quality of Lahore has consistently remained unhealthy, not just over the past couple of months, but also in the last few years with the onset of the ‘fifth season’ of smog. The air quality levels continue to dip after September until at least February.

According to the IQAir data, the second most polluted city in the world was New Delhi, India, with an air quality index of 210 ('Very Unhealthy'). The third most polluted city in the world on Wednesday morning was Chengdu in China with an air quality index of 179, categorized as ‘Unhealthy’.