Karachi remains on top in air pollution in Pakistan
KARACHI: The port city ranked atop in pollution in Pakistan as the level of hazardous particles in air reached to 238 in Karachi on Wednesday morning, ARY News reported.
According to recent reading of the Air Quality Index (AQI) this noon hazardous particulate matter in Karachi was recorded at 182.
AQI as high as 151-200 is considered unhealthy, while an AQI between 201 to 300 is more harmful and an AQI over 300 is dubbed extremely hazardous.
Air pollution of particulate matter in Lahore was recorded 152, Peshawar 153, Indian capital New Delhi 234, Kolkata 185 and Dhaka 172, as per the AQI reading.
Dr Zafar Iqbal, an environment expert, has said that in winter an increase in air pollution witnessed, change in the wind speed, wind direction and dropping minimum temperature increases air pollution, he said.
The smoke from factories and vehicular traffic in cities are among some factors adding to the air pollution, he added.
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, severely compromising the air quality.
Although southwestern winds blowing from the sea may work as a filter for the air in the city, these winds remain mostly suspended during winter, experts said.
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.