KARACHI - Pakistan’s largest city Karachi ranked first among the top ten most polluted cities in the world on the Air Quality Index (AQI). Average air quality index reading of Karachi recorded 220, while Lahore remained third from the top of the list. It is to be mentioned here that AQI as high as 151-200 is considered unhealthy, while an AQI reading between 201 to 300 is more harmful and AQI rate over 300 mark is extremely hazardous. The AQI calculation is based on five categories of pollution: ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide. Health experts have raised the alarm, warning that pollution can have detrimental effects on public health. Individuals with conditions such as eye discomfort, allergies, and respiratory issues are at a higher risk.