LAHORE: Smog continuing to haunt Punjab with bad air quality as Lahore remains on the top of the list of world cities having worst air quality, ARY News reported on Monday.
Lahore remained the most polluted city of the world with average 322 reading on the Air Quality Index, while Indian capital city, New Delhi remained the second on the AQI with 319 points.
China’s Wuhan remained third with regard to the worst air quality with 231 reading.
According to the reports of international media, burning of crop residue and garbage in northern Indian states causes dangerous hike in environmental pollution in the region.
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 termed extremely toxic.
According to experts, 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 a city.
The smoke produced by burning crop remnants, factories and burning coal, garbage, oil or tyres enters the atmosphere and the effects of this appear at the onset of winter and remain till the season’s end, experts said.
Thus, air pollution reaches to extremely dangerous levels, severely compromising the air quality.
The AQI is calculated on the basis of five categories of pollution: ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide.
