Choking Point: The World’s Most Polluted Cities

9 mins

Residents of cities around the world are breathing in deadly air particles that kill millions per year – and the climate crisis is making it worse

When it comes to air pollution, and the world’s most polluted cities, we need to take a deep breath. Or maybe not. For air pollution is the most severe environmental threat to our health globally – killing millions each year. 

With every breath we take we inhale deadly nano particles that come from dust storms, wildfires, and the combustion of fossil fuels, that can damage our lungs, hearts and brains and has been linked to cancer and millions of premature deaths. 

In many of the most polluted cities, citizens are warned to stay indoors and keep windows and doors shut rather than breathe in the choking atmospheric cocktail of pollutants.

And while many assume that the dire air quality is down to emissions from vehicles and industry, the climate crisis has a pivotal role that is endangering the health of billions worldwide. 

Polluted Cities

polluted city

All but one of the 100 most polluted cities were in Asia last year, according to a report by IQAir that tracks air quality around the globe. The majority – 83 – were in India, and all of them exceeded the World Health Organisation’s air quality guidelines by more than ten times.  

The problem? Fine particulate matter which is measured according to size, the biggest being PM10 (up to 10 micrometres in size) while PM2.5 (up to 2.5 micrometres in size)is the tiniest pollutant of all –and the deadliest. 

Air pollution from fossil fuels kills 5.1 million people worldwide every year while a further 6.7 million die prematurely from the combined effects of household and ambient air pollution

When inhaled it travels further into lung tissue where it can enter the bloodstream. It has been linked to heart and lung disease, cancer, asthma and other respiratory illness along with cognitive impairment in children. 

Deadly Air

child looking out of window at polluted cities and smog

But it is deadly, with air pollution from fossil fuels killing 5.1 million people in polluted cities worldwide every year, according to a study published in the BMJ. A further 6.7 million die prematurely from the combined effects of household and ambient air pollution WHO says

Only a teeny nine per cent of the 7,800 cities whose air quality is analysed globally met the standards set by WHO, which says average annual levels of PM2.5 should not exceed five micrograms per cubic meter.  

The average in the Arab world is 59 micrograms per cubic metre. In the US the mean annual exposure to PM2.5 is seven micrograms per cubic metre. The global average is 46.

‘We see that in every part of our lives that air pollution has an impact,’ IQAir Global CEO Frank Hammes told CNN. ‘And it typically, in some of the most polluted countries, is likely shaving off anywhere between three to six years of people’s lives. And then before that will lead to many years of suffering that are entirely preventable if there’s better air quality.’

Begusarai, a city in northern India’s Bihar state, was the world’s most polluted city last year with an average annual PM2.5 concentration of 118.9 — 23 times the WHO guidelines. It was followed by Guwahati, Assam; Delhi and Mullanpur, Punjab.

The worst performing regions were central and south Asia – home to all four of the most air polluted countries: Bangladesh, Pakistan, India and Tajikistan.

Just 10 countries and territories had ‘healthy’ air quality: Finland, Estonia, Puerto Rico, Australia, New Zealand, Bermuda, Grenada, Iceland, Mauritius and French Polynesia.

Climate Crisis Effect

The IQAir report named the climate crisis, driven by the burning of fossil fuels, for influencing air pollution levels. As climate change alters weather patterns, the changed in wind and rainfall affects the dispersion of pollutants. Extreme heat will only make air pollution worse in our polluted cities as will severe wildfires and more intense pollen seasons. 

‘We have such a strong overlap of what’s causing our climate crisis and what’s causing air pollution,’ Hammes said. ‘Anything that we can do to reduce air pollution will be tremendously impactful in the long term also for improving our climate gas emissions, and vice versa.’

In the UAE, The Ministry of Climate Change and Environment is taking steps to develop a strategy for cleaner air with The UAE National Air Quality Agenda 2031. 

It includes creating cleaner, more sustainable transport with the UAE Railway Programme and the Dubai Autonomous Transportation Strategy, which sets a target of having 25 percent of transport in Dubai running autonomously by 2030. Another target is that all public transport buses, taxis and limousines in Dubai will be electric or hydrogen powered by 2050. 

Clean Air Strategy

traffic jam meaning car fumes pollute the air

The will for change locally is certainly here, as it is globally where governments and NGOs are introducing measures to clean up transportation, particularly in cities. A 2020 study by consultancy firm Kantar predicted that private car trips will drop by 10 per cent on average by 2030 to make up less than half of all city journeys, while public transport, walking and bicycle will all increase in popularity. 

Yoann Le Petit from environmental campaign group Transport and Environment says that growing awareness of pollution and congestion caused by car use was helping to drive change but that polluted cities should go further.

‘We are witnessing this trend, but we should not just relax and lay back,’ he said. ‘We should really make sure that the alternatives to a private car are zero-emission, are shared and are attractive at the same time.’

Not all cities ethical ‘solutions’ are popular. Parisians recently voted to banish public rental self-service e-scooters from their boulevards, 15,000 of which were introduced five years ago and touted as a cheap, easy, environmentally friendly way to get around the congested city. 

However, their use came with risks. They were cited as a contributing factor in several deaths and hundreds of accidents. Anyone who visited Paris in the last few years would also have noticed they were frequently left strewn across pavements and in roads. 

Contractors Lime, Dott and Tier criticised the ban as a step back for sustainable transport ahead of this summer’s Paris Olympics.

The Parisian e-scooter debacle is an example of how good environmental intentions can go awry. In London, for example, a recent roll-out of the city’s Ultra Low Emissions Zone (ULEZ), through which drivers of older vehicles must pay to drive, has proved a political hot potato, deeply unpopular in many of the city’s outer boroughs where people rely more on their cars.

Many owners of old cars have had to scrap their vehicles and buy newer ones. The system has been criticised for penalising people on lower incomes. 

Sustainable Solutions

picture of city half polluted and half green and clean

Other cities have had more success. Braga in Portugal has worked with over 100 companies to pedestrianise streets. The city also organised a ‘Mobility Safari’ to illustrate the importance of decarbonisation and sustainable mobility and launched the first phase of its bike-share service.

Other schemes that have won plaudits are electric buses and pollution-reduction traffic calming measures in Sofia, Bulgaria, and cycle highways in Zagreb, Croatia.

Last year the World Health Organization released details from its world air quality database which showed almost the entire global population (99 per cent) breathes air that exceeds WHO air quality limits and threatens health 

But even Europe, with its reputation of being ahead of the curve in sustainability, could do better. An assessment last year of efforts to get European city dwellers into environmentally friendly transport found many urban centres were lacking. 

Cities were ranked by the Clean Cities Campaign (CCC) according to five criteria: how much space they created for people, how safe their roads are, access to climate-friendly mobility, what policies they have put in place for reducing greenhouse and polluting gases, and their air quality. 

Clean Cities Campaign

Oslo has the cleanest air

The best performers were in northern Europe, in particular the Nordic countries. Oslo topped the list, with Amsterdam second, followed by Helsinki, Copenhagen, Paris and Stockholm. Naples in Italy was bottom, followed by three Polish cities: Krakow, Warsaw and the ‘Tri-city’ coastal agglomeration of Gdansk, Sopot and Gdynia.

Barbara Stoll, director of the Clean Cities Campaign, said: ‘This should be a wake-up call for Europe. Without cities making much bigger efforts we will not get close to reaching zero-emissions by 2050 as promised by the European Green Deal. 

‘This can also be an opportunity for cities to become more liveable. Clean, efficient, and reliable transport makes cities so much more attractive, and millions of Europeans are looking for relief from dirty air. We should acknowledge that Oslo and Amsterdam are not first and second by accident. It is about getting the policies right.’

Much has been made of the bright future that awaits, thanks to emerging technologies such as driverless cars, hydrogen fuel cells and even electric flying taxis and hyperloops, all of which it is hoped will replace gas guzzling cars and lorries at some point in the future. But time is running out. The world is getting warmer and the air in it is getting dirtier.

Last year the World Health Organization released details from its world air quality database which showed almost the entire global population (99 per cent) breathes air that exceeds WHO air quality limits and threatens health. 

The data from over 6,000 cities in 117 countries which monitor air quality showed that people living in them are breathing unhealthy levels of fine particulate matter and nitrogen dioxide, with people in low and middle-income countries suffering the highest exposures.

The data spurred WHO to highlight the importance of curbing fossil fuel use and taking other tangible steps to reduce air pollution levels. Urgent action is needed because if we don’t act soon to reverse the decline, we will reach choking point and face a life trapped indoors while our polluted cities suffocate. 

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