Addressing air pollution — time to change tack?

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Last winter Karachi and Lahore were, once again, classified among cities with the most polluted air in the world. High air pollution compelled the government to take drastic measures including shutting schools and public offices, closing off parks and other public spaces, and advising people to stay indoors.

But these are simply short-term emergency actions and do not influence the long-term effects of breathing bad air. It is estimated that air pollution in Pakistan contributed to the premature death of over 200,000 people, caused a loss of 6.5% of GDP and lowered average life expectancy by almost 3 years.

With the arrival of spring, the air is clearing. People can now literally start breathing once again. But will the problem return in 8-9 months? And, more to the point, are there things we can do to prevent or at least reduce this annual phenomenon?

The causes of the poor air quality in our cities are well understood. It is a mix of human activity in and around the city, exacerbated by ambient factors such as temperature, air currents and topography.

Air pollution comprises a cocktail of chemicals, usually expressed in terms of the concentration of fine particulate matter - which in itself comprises different types of chemicals with different toxicities. The finest among these (PM2.5) are considered the most toxic since they easily enter the human body.

In Pakistan, the main sources of pollution are: transport and traffic; power plants, industrial units and factories, including the much maligned brick kilns; and burning of crop stubble, other agriculture residues and solid municipal waste, including plastic waste.

Pollution peaks in the winter months as air currents are weak and rainfall is low. As a result, chemicals and particulates are not blown away by the wind or washed away by rain. Local pollution stays local. Another factor is temperature inversion. Cold air is trapped at ground level by a layer of warmer air above it - like a pot with a lid. Particulate matter and other pollutants thus remain trapped in the lower atmosphere where it is most harmful for humans.

Moreover, if the difference between day and night temperatures is substantial, ground fog can also form, particularly in the morning hours. This is a phenomenon that particularly affects Lahore and other cities in Punjab.

The fog particles are tiny droplets of water suspended in the air. Chemicals such as nitrogen dioxide and sulphur dioxide react with these water particles to form corrosive acids. Dust, ash and other particles also piggy back on these water droplets.

This mix of corrosive acids and particulate matter play havoc with the delicate membranes in the nose and lungs, restricts the absorption of oxygen, and also enters into the blood and other organs. It is associated with strokes, cardiovascular diseases, lung cancer and arthritis. Babies and young children are particularly vulnerable, and there is strong evidence linking air pollution and permanent damage on the development of their brains.

The actions needed to address the problem are well understood and are well articulated in the Clean Air Policy approved in 2023.

First, reduce traffic related pollution by improving mass transport systems; raising emission standards and fuel quality; incentivising the use of electric vehicles, particularly motorcycles which have detachable batteries that do not need fixed charging points; and selective restrictions on the use of the most polluting vehicles, such as diesel trucks, when pollution levels rise above a certain level.

Second, reduce emissions from industrial sources. Currently there are few zoning restrictions which mean that factories, workshops and power generations units can be set up almost anywhere. New industrial activities must adhere to higher standards. They also need to be located keeping in mind topography and wind directions - two factors that are critical determinants of how their emissions are dispersed. As importantly, existing laws on emissions should be applied and, where necessary, highly polluting units close to cities should be relocated.

Third, stop the burning of crop residues that not only creates pollution but also kills most of the organisms living in the soil. This negatively affects soil fertility and health, and eventually the productivity of crops. There are well-proven technologies that do not require burning of crop residues and can, in fact, reduce cost and increase yields. A strong extension effort, combined with government restrictions, could substantially reduce, or even eliminate, burning of crop residue. There is an analogous situation with urban solid waste, including plastics, that could easily be disposed much better than is being done now.

Although both the problem and the solutions are well-known, the government has consistently demonstrated its incapacity to significantly improve the situation. Undoubtedly, there are some real obstacles. One of them is the lack of public funds that could, for example, be used to incentivise greater use of public transport or reduce improper disposal of solid municipal waste. Another obstacle is the lack of technically competent and dedicated government staff - particularly at local level - that could, for example, interact with farmers to explain the damage to soil caused by burning of crop residue.

However, in our opinion the most critical obstacle is the unwillingness of the government to take the political risks of decisive action such as restrictions on traffic and emissions; zoning for industrial units; and banning the burning of crop residues.

Given this lack of political will, policy reports, strategy documents, academic articles and press reports will unlikely have impact.

So maybe the time has come to completely change tack - move away from expecting government to take action and try to use "market based solutions". One way to move forward would be to engage with the rapidly growing market for carbon credits i.e. companies that cannot easily reduce their carbon footprint could "buy" carbon offsets. Thus if a large petroleum firm cannot reduce it emissions, it could pay others to do so on their behalf. Typically such carbon offsets are related to production of renewable energy or reforestation. However, why not try to use carbon offsets to pay farmers to not burn crops, or to get highly polluting units to install air filter systems?

Going down this path would require substantial work. Maybe some of the large private sector companies or multinationals operating in Pakistan could take the lead, possibly also engaging with various industry associations and Chambers of Commerce.