ISLAMABAD: The eastern Pakistani city of Lahore was ranked the second most polluted city in the world on Thursday morning, according to an IQAir listing, which showed it had an Air Quality Index (AQI) of 470, which is considered ‘hazardous.’
An annual global survey by the Swiss maker of air purifiers had put Lahore as the city with the worst air in the world in 2022.
Last week heavy pollution-fueled smog forced authorities to close schools and markets in Pakistan’s most populous province of Punjab, of which Lahore is the capital.
By Thursday afternoon, Lahore’s AQI had slipped to 252, which is considered “unhealthy.”
Heavy smog has blanketed Lahore since last week, reducing visibility and leading residents to complain of a threat to their health.
“PM2.5 concentration in Lahore is currently 40.4 times the WHO annual air quality guideline value,” said IQAir, which measures air quality levels based on the concentration of lung-damaging airborne particles known as PM2.5.
The WHO recommends a maximum PM2.5 concentration of 5 micrograms per cubic meter.
Schools, offices, restaurants and businesses, aside from priority services like pharmacies, hospitals and courts, remained closed last week in Punjab to limit residents’ movement outside, according to a directive from the provincial government.
While Delhi topped the list of most polluted cities on Thursday, Pakistan’s Karachi was also ranked at number 3, with an AQI of 179, which is considered “unhealthy.” PM2.5 concentration in Karachi is currently 21.9 times the WHO annual air quality guideline value
Growing industrialization in South Asia in recent decades has fueled growing pollutants emanating from factories, construction activity and vehicles in densely populated areas.
The problem becomes more severe in cooler autumn and winter months, as temperature inversion prevents a layer of warm air from rising and traps pollutants closer to the ground.