LAHORE: Punjab’s capital city and Pakistan’s cultural hub Lahore remains on the top of the world’s most polluted cities list on Thursday, ARY News reported.
Overall reading of Lahore on the Air Quality Index measured 348 today. In some parts of the city the AQI reading crossed 400 level. The air quality in Gulbarg area of the city measured 461 on the air pollution scale.
The air quality reading recorded 422 at Lahore’s posh locality Johar Town.
The AQI is calculated on the basis of five categories of pollution: ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide.
AQI as high as 151-200 is considered unhealthy, while an AQI rating between 201 to 300 is more harmful and AQI over 300 is extremely toxic.
According to experts, an increase in air pollution used to be recorded in the winter. A change in the wind speed, wind direction and sliding minimum temperature increases air pollution.
The air becomes heavier in the winter as compared to summer, causing poisonous particles in the atmosphere to move downwards and making the atmosphere polluted. As a result, a layer of polluted particles, including large amounts of carbon and smoke, covers an area.
The smoke produced by burning crop remnants, factories and burning coal, garbage, oil or tyres enters the atmosphere and the impact of this appear at the onset of winter and remains till the season’s end, experts said.