Lahore tops world's 'most polluted' cities' list for second day

• Citizens have been advised to avoid outdoor exercise.
• New Delhi retains its position as second most polluted. 
• Karachi's air quality drops as megapolis ranks third.
  

Lahore topped the list of the most polluted cities in the world on Wednesday for the second time in a row, with an even higher air quality index (AQI) than yesterday as the smog situation worsens in the provincial capital.

The IQAir data released today showed that Lahore's air quality dropped to 503 on the US AQI. 

As per the air quality classification by IQAir, the atmosphere becomes "hazardous" to health after the AQI crosses the 300 mark. 

An AQI of 0-5 is considered "good", 51-100 is considered "moderate", 101-150 is "unhealthy for sensitive groups", 151-200 is simply "unhealthy", 201 - 300 is "very unhealthy", while more than 301 degrees indicates "hazardous". 

IQAir measures air quality levels based on the concentration of lung-damaging airborne particles known as PM2.5 — and this is 55.6 times more than the World Health Organisation (WHO) air quality guideline value in Lahore.

Meanwhile, New Delhi, India, retained its position as the second most polluted city on the scale, with an AQI of 366. 

The third most polluted city in the world today is Karachi, where the AQI is 166. 

Here, the air quality is "unhealthy" for the citizens. 

Medical experts have advised those with respiratory issues such as asthma and dust allergies to practice extreme caution to stay safe from the effects of air pollution. 

In the wake of existing situation, Punjab Environmental Projection Department issued separate guidelines for schools and other sectors. 

As per the notification, school timings have been changed to 8:45am, taking effect from October 28 till January 31, 2025. The school administrations have been directed to organise students' assemblies indoors. 

Citizens have been advised to avoid outdoor exercise, keep their doors and windows closed to prevent dirty air, wear mask and check their vehicles' fitness among other precautionary measures. 

Meanwhile, activities like fireworks have been banned till January, 31, 2025. 

The provincial authorities rush to tackle the worsening smog crisis with all arrangements made to deal with the situation, Senior Punjab Minister Marriyum Aurangzeb said last week.

The government may also adopt the option of artificial rain to reduce increasing smog.

The quality of air deteriorates when colder days approach, as pollution spirals with cooler temperatures taking hold. Lahore and New Delhi are mostly the most polluted cities.

Bad air quality is a major threat to the health as citizens in the polluted cities develop several medical issues, especially respiratory problems.

According to a report published last year which flagged the growing burden of hazardous air on health, rising air pollution can cut life expectancy by more than five years per person in South Asia, one of the world's most polluted regions. 

According to environment lawyer and activist Ahmad Rafay Alam, the perception that poor quality is a seasonal Lahore issue is not true. 

"Air pollution is a regional and year-round public health emergency."