With accelerated rates of urbanization and growing densities of urban communities, it has become more crucial than ever to keep the global pollution levels in check. Cities make up only 2% of the world’s area but this area contributes to more than 60% of greenhouse gas emissions in the world, while at the same time consuming 78% of the world’s energy.
Urban pollution is measured by various factors such as air quality, condition of water bodies, access to clean drinking water, waste management, cleanliness of public spaces, and presence of green spaces. Factors like public safety as well as light and noise pollution during the night are also to be examined.
With regard to the mentioned criteria, the following cities are the ten world’s most polluted cities in 2021.

1. Kathmandu, Nepal | World’s most polluted cities

Haphazard expansion of the capital city due to uncoordinated planning makes Kathmandu one of the world’s most polluted cities in 2021. The Bagmati river in Kathmandu is highly contaminated due to insufficient wastewater treatment facilities and low levels of awareness among the people concerning waste disposal. Building construction processes and vehicular exhaust emissions add to air pollution as well as noise pollution. 

Deteriorating air quality levels also occur due to winter inversion, wildfires, and cross-border industrial pollution. Smoky fires used in rural neighbourhoods add to the high levels of air contamination. This consequently has led to chronic illnesses among people such as diabetes, heart diseases, and lung diseases. 

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The Bishnumati River in Kathmandu which feeds into the even more polluted Bagmati River theculturetrip.com
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A smoggy day in Kathmandu, Nepal, March 30, 2021 _©dailysabah.com

2. Tetovo, North Macedonia

The most polluted city in Europe, Tetovo, is located in the northwest of North Macedonia, on the foothills of the Šar mountains. The city is largely dependent on the highly polluting lignite coal-powered industry which serves domestic heating purposes. Automobile emissions from old obsolete vehicles are another major cause of pollution. Improper waste disposal and harmful gases released from industries add to the toxicity of the air. 

As per 2018 statistics, 38% of all deaths in Tetovo are directly caused because of air pollution. Illegal logging in the nearby mountain forests reduces the green cover and this, in turn, harms the ecosystem even more. Drinkable water is also lacking in Tetovo because industrial waste is continuously dumped into the city’s rivers.

10 world's most polluted cities in 2021 Sheet3
Air pollution in Tetovo _©vimeo.com

3. Faridabad, India

Faridabad, located in Haryana, is the satellite city of India’s capital, New Delhi. Being a major industrial hub, it has witnessed uncoordinated urban sprawl with a large number of construction sites and road repair works. This adds a huge amount of micropollutants to the air, including hazardous heavy metals. 

Additionally, the open burning of mixed garbage containing synthetic materials like plastic and rubber mixed with wood and dry leaves results in high levels of carbon emissions in the city. The use of outdated vehicles in the city has also contributed to high levels of pollutants in the air. Faridabad has air pollution levels that are 25 times higher than the safe limit.

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Air pollution is 25 times higher that safe limits in Faridabad _©dailypioneer.com

4. Kabul, Afghanistan

In Kabul, one of the most polluted capital cities in the world, about 3000 people die annually due to respiratory diseases caused by contaminated air. The use of poor-quality fuel, raw coal, and even plastic materials and car tires, majorly contributes to the dangerous levels of air contaminants. 

On top of this, a lack of forestland has led to a situation where there is no carbon sink in the city to absorb the threatening amount of carbon emissions. Irregular usage of groundwater, lack of sufficient infrastructure, and low rainfall have led to a scenario where 80% of drinking water is polluted, causing food poisoning and other diseases.

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Aerial view showing Kabul amid heavy smog conditions in 2021 _©aa.com.tr

5. Accra, Ghana | World’s most polluted cities

In Accra, the capital city of Ghana, diseases like asthma and cardiovascular diseases are very common. Poisonous fumes from automobiles, open burning of waste, and unhealthy heating methods for cooking are the main reasons for the unimaginable levels of air pollution. The pollution levels change with the changing seasons and are particularly high during the dry season due to the rising desert dust. 

In 2018, Accra became the first African capital city to join the ‘BreatheLife movement’ by the Urban Health Initiative. Many community initiatives have been taken since then, but there is a long way to go towards completely clean air conditions.

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The polluted Odaw River divides the Old Fadama slum from the Agbogbloshie scrapyard _©medium.com
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A worker throws a mass of cables into a fire already burning in 2018 _©medium.com

6. Ulaanbaatar, Mongolia

Ulaanbaatar is characterized by a thick, sooty atmosphere caused by the extensive usage of coal for domestic purposes. Industrial emissions and road transport pollution are other factors that cause diseases like pneumonia to be rampant in the city. Many people in this highly polluted city are almost oblivious to the fact that healthy lungs can exist. 

In schools, air purifiers are used in every single room so that the kids can grow healthily. Lack of electricity and basic infrastructure led to the widespread use of unhealthy fuel causing the city to reach this state of noxiousness socially and environmentally.

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Dust-filled air over Ulaanbaatar _©blogs.ntu.edu.sg

7. Beirut, Lebanon

The city of Beirut faces high levels of air pollution due to the presence of many industries like cement, food processing, mineral production, oil refineries, etc. Irresponsible waste disposal is observed in the coastal tourist hub. The highest levels of air pollution are during the winter due to the fuels used in heating. 

On August 4, 2020, almost 3000 tonnes of ammonium nitrate exploded in Beirut’s port, releasing toxic gases like nitrogen oxides and ammonia into the atmosphere. Sewage and medical waste from the COVID-19 pandemic are said to have polluted the city’s waters. Large numbers of dead fish were washed up on the Litany River shore in Beirut due to high toxicity levels in the water.

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Dead fish washed upon Litany river’s shore _©reuters.com
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Beirut Explosion in 2020 _©middleeasteye.net

8. Ghaziabad, India

In Ghaziabad, high air pollution levels are chiefly due to traffic congestion and crop burning activities. Post winter in 2021, slow winds coupled with smog caused the pollutants to settle down densely in the air without dispersing. The ingestion of heavy metals in the peri-urban and urban-industrial clusters in the city has resulted in poor groundwater quality. 

There have even been nauseating instances where the supply water has been mixed with sewer water causing diseases to many. Poor quality construction has caused the collapse of many residential and commercial buildings and 102 buildings are said to be at risk according to an audit for which smart retrofitting has been recommended.

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Industrial pollution in Ghaziabad _©delhincrnews.in

9. Dhaka, Bangladesh

Being one of the most densely populated cities in the world as well as one of the least developed nations in the world, Dhaka, the capital city of Bangladesh is faced with a challenging situation to deal with. The majority of the air pollution in Dhaka comes from brick kilns which use coal and wood as their primary energy source. The government has planned on enforcing an end to the usage of all brick kilns by 2025. 

The burning of rubber tires is another reason why highly toxic gases are produced. Vehicular and industrial emissions are also major contributors to harmful living conditions in Dhaka. Industrial waste and sewage discharge into the rivers around Dhaka City have given rise to very unhygienic conditions around the water bodies.

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Textile dyes polluting rivers in Dhaka _©iamrenew.com
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Industrial Waste dumped near Dhaka rivesr _©en.prothomalo.com

10. Noida, India | World’s most polluted cities

Noida is the most polluted city as well as the most unsafe city in India. There is an almost permanent cloud of dust in Noida. Lack of cleaned public spaces and non-adherence to dust-control rules at construction sites has led to such severe conditions. 

Constant migration to Noida from the surrounding cities, towns, and villages, due to its proximity to New Delhi has caused a rapid growth of population which has not been balanced by adequate infrastructure. This has led to sprawl, unhealthy settlements, and irresponsible maintenance of the urban fabric by the communities as well as the government.

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Smog in Noida _©hindustantimes.com

Transformation of polluted cities into breathable and beautiful urban spaces can happen only with a change in public policies, nature-friendly urban planning, and adaptable urban design. Creating awareness among the public about environmentally friendly practices is another big step that can make or break the situation, especially in developing countries. 

In the future, urbanization need not be associated with pollution, disease, and unhealthy living standards. Research indicates that by 2050, 70% of the world population will move to urban areas. People migrating to cities is inevitable, and hence it is time to turn the development of polluted cities into something that revives the ecological as well as socio-economic layers of the city.


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Devaki Kesh is an architect passionate about regenerative building techniques and revival of urban landscapes. She is a lifelong learner and loves to express herself through writing, art and music. She is a mother to five cats and two dogs.