Lahore on top again as air quality worsens amid persistent smog

Residents in Lahore continue to breathe toxic air as the city bounced back to the top spot on the global pollution chart on Friday following a brief respite from the smog that has choked Punjab for weeks.

The Punjab government eased the restrictions in Lahore and other smog-hit cities in the wake of an improvement in the provincial capital's air quality on Thursday.

However, the relief was short-lived as the megapolis witnessed a rise in pollution levels again, with the air quality index (AQI) reaching 502 early Friday morning on the Swiss group IQAir's list.

As of 9:30pm, the AQI was recorded at 485 but still above the 300 mark, which is considered hazardous, while the level of PM2.5 particles was also more than 63.6 times higher than the level deemed acceptable by the World Health Organisation.

Meanwhile, India's New Delhi slipped to the second spot in the rankings of cities with worst air quality, after sitting atop the global pollution charts.

In Pakistan, the second most polluted city was Multan, with a "hazardous" 354 AQI. Faisalabad and surrounding areas also witnessed a deterioration of air quality, causing breathing issues and eye infections.

The Punjab government announced on Thursday the resumption of outdoor activities as the air quality and smog crisis improve in Lahore and other cities of the province. 

Punjab, home to more than half of the country's 240 million people, remains blighted by the toxic smog-laden air travelling from neighbouring India due to dust, emissions, and smoke from illegal stubble burning on fields.

The dense smog that hit hazardous levels earlier this month was described by Senior Minister for Environmental Protection Marriyum Aurangzeb as a "national disaster."

However, on Thursday, the provincial government announced the resumption of outdoor activities as the air quality and smog crisis saw some improvement in Lahore and other cities of the province. 

The thickening smog had prompted the authorities to take drastic actions, including the closure of schools and a complete ban on people's entry into park, zoos, playgrounds and all other public places besides open-air cooking at restaurants and construction sites.

Every Lahore winter, a mix of low-grade fuel emissions from factories and vehicles, exacerbated by seasonal crop burn-off by farmers, blanket the city, trapped by cooler temperatures and slow-moving winds.

As per a WHO warning, breathing toxic air has catastrophic health consequences including strokes, heart disease, lung cancer and respiratory diseases due to prolonged exposure.