Lahore's sick lungs.

WHEN environmental lawyer Ahmad Rafay Alam started the cycling group Critical Mass Lahore 14 years ago in the city, his plan was to promote 'sustainable urban transport' as well as the idea that 'women have a right to be in public spaces'. Both ideas caught on and have found resonance in Karachi and Islamabad, but Alam himself gave up cycling because of the traffic, which had become too dangerous to navigate.

HRCP director Farah Zia says cycling brings not only 'immense pleasure' to her but also a sense of 'freedom'. Sadly, like Alam, the sea of vehicles keeps her from pedalling to work every day, so she restricts herself to cycling around her neighbourhood.

Alam resumed cycling during the 2021 Covid-19 lockdown. He recalled that 'once in a lifetime' event when the 'air was cleaner, the sky bluer' and the roads rid of motorbikes and cars. But life was back full throttle in 2022 and has picked up even more speed since then.

No lessons were learnt from the lockdown, it seems, and the 2022 World Air Quality Report, published earlier this month, is evidence of this. IQAir, a Swiss air quality technology company which published the report, ranked Lahore as the most polluted city in the world. It had ranked 15th in 2021. Peshawar, at fifth position, did not fare any better, and came fourth in the Central and South Asia region.

Two recent reports underscore the urgency of collective action to curb emissions.

What is making Lahore's air sick?

To understand this, we need to first acquaint ourselves with the very tiny but extremely hazardous particulate matter (PM), found in the air in solid or droplet form. These can be 10 micrometres, 2.5 micrometers or even less in diameter. By way of comparison, PM2.5 is one-thirtieth the width of a human hair, which is between 70 to 90 micrometres.

The smaller particles are so tiny that several thousand can fit in the full stop at the end of this sentence. These miscreants (including sulphates, nitrates, black carbon and ammonium) travel deep into our lungs and enter our bloodstream, causing serious lung and heart diseases. In fact, scientists say, air pollution has reduced the average life expectancy across Pakistan by up to 2.7 years.

The WHO global air quality guidelines to help governments and civil society reduce human exposure to air pollution and its adverse effects have recommended an annual PM2.5 guideline level of 5 ug/mA3 and a daily PM2.5 guideline level of 15 ug/mA3.

The report by IQAir has listed...