KARACHI: Country’s busiest metropolises Lahore and Karachi ranked fourth and tenth respectively on the latest global Air Quality Index (AQI) on Saturday.
Bahawalpur was measured to have 327 hazardous particulate matter. Lahore recorded a reading of 194, Rawalpindi 189, Raiwind 170, Karachi 167, and Multan 165, according to the index.
AQI between 151-200 is considered unhealthy, between 201 to 300 harmful and over 300 is hazardous and may prompt emergency condition alerts.
“Air pollution […] claims tens of thousands of lives, devastates the health of millions, and denies other rights, like the right to education, when children cannot go to school,” said Omar Waraich, South Asia campaigns director for Amnesty International.
“This is a human rights crisis,” he said.
According to experts, 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 the city.
The smoke produced by factories and by 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 extremely dangerous levels in cold weather, severely compromising air quality.
Although southwestern winds blowing from the sea in Karachi may work as a filter for the air, these winds remain mostly suspended during winter, according to experts.
They noted that winds blowing from the northeast increase the concentration of hidden polluted particles, and a healthy atmosphere in such a situation is subject to rainfall, which washes off all polluted particles.
The AQI is calculated based on five categories of pollution: ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide.
