Her eyes were teary. She felt a little bit of tightness in her heart. Her breathing became heavy. No, she was not suffering from a broken heart and she did not have mental anxiety either. Like many other residents of Kathmandu, she was showing some health symptoms of the effects of air pollution. Smoke, dust and harmful gases such as carbon mono-oxide, nitrogen oxides and sulphur oxides have filled Kathmandu’s air. And their effects have become more pronounced in recent years.

The health problems caused by air pollution could be varied in terms occurrence, impact and severity. It could be in a relatively less detrimental form such as occasional headache, coughing and sneezing. However, long-term exposure can severely affect respiratory health and heart condition, and the affected ones are likely to develop asthma, pneumonia and even lung cancer. Besides human health, air pollution can affect various elements of nature. The accumulated pollutants have the potential to reduce visibility and diminish the aesthetic beauty of a place. The oxides of nitrogen and sulphur intermingle with rain resulting in acid rain, which can damage crops, buildings and water bodies.

Kathmandu’s air pollution rose to higher levels during the dry period of March 2016. The Pollution Index portal of a Serbia-based research website ranked Kathmandu as the third most polluted city in the world, with a pollution index of 96.66. Now, in September, 2016 even after heavy monsoon, the pollution level is almost the same. At present, Kathmandu is in the fourth position with a pollution index of 96.38. Both statistics show the critical condition of the air that the valley residents breathe.

Causes and effects

The polluted air of Kathmandu is the consequence of multiple interrelated factors. First, the rate of increase in pollution became quite rapid in Kathmandu especially after the pro-democratic movement of 1990. Kathmandu’s population increased from 675,341 in 1991 to 1,744,240 in 2011—a growth rate of 4.67 per annum. The centralised governance system with opportunities for better education, employment and health encouraged people to migrate to Kathmandu. More people mean more demand for resources, more consumption and more household emissions.

Along with an expanding population, Kathmandu witnessed a dramatic rise in the number of private as well as public vehicles in the past decade. The Department of Transport Management has estimated the annual motorisation rate to be 12 percent. In 2010, 575,417 vehicles were registered in Kathmandu and the number of registration in the Bagmati zone increased to 688,028 in 2012-13. These vehicles have not only contributed to air pollution, but have also become one of the leading causes of traffic congestion in Kathmandu.

Traffic congestion was at least partly responsible for the road expansion drive that the government initiated, but it further deteriorated Kathmandu Valley’s air quality. More than 2,000 trees have been felled for this expansion project. The removal of trees not only tarnished the beauty of the place, but also damaged the natural air filter. A study has shown that tree leaves can capture more than 50 percent of

particulate matters. Now, Kathmandu has lost a significant portion of its trees that were capable of combating air pollutants.

Since Kathmandu is the economic hub of the country, it is the place with numerous small and large scale industries related to food, beverages, cement, textile and metallurgy. These industries directly or indirectly harm the local atmosphere with emission of toxic fumes and gases. Moreover, due to regular power cuts, the use of diesel generator by industries has increased, which further adds air pollutants to the atmosphere. The industrial statistics of 2013-14 reported that about 137 industries were registered during that period in Kathmandu. This indicates an additional growth of industries in the future and could be correlated with decreasing air quality.

Besides anthropogenic factors, the valley topography itself is responsible for exacerbating the air pollution problem. The bowl-shaped structure created by the surrounding hills often restricts the wind movement and capture the air pollutants in lower atmosphere. Therefore, air pollutants remain in atmosphere for a longer period.

Right to clean air

Living in a healthy environment is a basic human right of every citizen. Necessary measures should be taken to control and manage air pollution. Environmental policies and regulations should be revisited and effective implementation should be carried out at local, regional and national levels. Emissions from vehicles and industries should be regularly monitored and certain fines and penalties should be imposed on heavy polluters.

Similarly, the government should promote and subsidise cleaner transport systems. Road expansion should not be carried out in a haphazard manner. And industries should adopt appropriate technologies for reducing harmful emissions. All the pollutants cannot be controlled immediately and the results may not be instant. Yet, it is high time all stakeholders started adopting suitable approaches to restore our environment to its former condition.

Shrestha is a researcher at the Institute for Social and Environmental Transition-Nepal