Have you ever looked at pictures of a city skyline and noticed a haze blurring or shrouding the view? Unless it’s a naturally foggy day there’s a very good chance that that’s air pollution. When we’re in cities it isn’t always something we can see but, in just about every city around the world, it’s there.

Whilst living in Perth almost 20km away from the city centre this was something I saw regularly. One major problem for the city was dust and small particles were blasted into the air from mining in Western Australia and carried by winds across the city.

Back to the UK and today is Clean Air Day – an annual campaign to highlight just how big a problem air pollution is and the dangers of not tackling it. But why is it such an important issue and why are we so far behind other major cities in Europe?

The Importance of Having Clean Air

We can’t always see it but air pollution in many of our cities is a huge problem. The World Health Organisation (WHO) has set limits for air pollution that are unsafe to human health if they are passed. In the UK alone, there are almost 2000 locations around the country that regularly surpass that safe limit.

In many busy urban areas it’s even worse – levels of air pollution are often recorded at three times the WHO safe daily limit. For those of us living in cities and busy urban areas we can be exposed to harmful pollutants every day for an extended period of time which can become increasingly dangerous.

It’s estimated that around 36,000 people die in the UK from respiratory-related diseases compounded by air pollution. Illnesses and other diseases related to air pollution are also on the rise and are putting increasing amounts of pressure on health services in the UK and around the world.

So tackling air pollution is not just for the environment. It’s not just for our health and the benefit of society either. There is an economic argument for reducing air pollution as low as we can, and we need to do it as soon as we possible!

WHO Limits

The WHO has set out a number of safe limits for PM2.5, PM10, O3, NO2 and SO2 in our cities. The figures below show the safe limits to be exposed to each of the pollutants across an entire year and the daily, or smaller, maximum safe limits. All figures are measured in micrograms per metre cubed.

PM2.5 Annual mean 10µg/m3
Daily mean 25µg/m3
PM10 Annual mean 20µg/m3
Daily mean 50µg/m3
O3 8-hour maximum 100µg/m3
NO2 Annual mean 40µg/m3
1-hour mean 200µg/m3
SO2 Daily mean 20µg/m3
10-minute mean 500µg/m3

Exceeding those limits in the short and long term can have devastating health impacts. In areas of China that are heavily industrialised and suffering with incredibly poor air quality, asthma and respiratory-related diseases are increasing rapidly. Schools are often shut on days when it is particularly bad with people encouraged to stay inside.

Current UK Air Pollution

Yesterday morning I looked at the UK air pollution data collected by the Air Quality Index (AQI) to see what the air quality across the UK was like. The numbers on the map below are based on PM10 data and safety limits. Anywhere green and below 50µg/m3 is considered good, even if it exceeds the safe annual average for us to be exposed to. If the numbers are yellow then they exceed WHO guidelines daily limit and present a danger to human health. Unfortunately, my home town of Southampton is one of these locations.

Screenshot 2019-06-19 at 09.44.23.png

In the past, the UK has had to answer to the European Court of Justice for its poor air quality a number of times. EU legislation is particularly stringent when it comes to air pollution and the UK is struggling to tackle it.

The UK Government has released a clean air strategy for 2019 (that can be found here) in an attempt to reduce air pollution in UK cities. Given the dangerous levels of particulates in the air that continue to plague our urban areas, it will be interesting just how big an impact this strategy has, especially as we leave the EU, and very likely the strict legislation we have struggled to abide by.

Our Cities are Choking

As more and more of the global population move into urban areas, ensuring good air quality is becoming increasingly vital in our cities. Higher populations usually mean more cars on the road and cities become hubs for different industries that can also impact the air quality of urban areas.

To understand the impact of car and transport use in busy urban areas, measurements of air pollution were taken on a number of Sundays and the Sunday of the London Marathon when a number of streets were closed. Results from that study found that there was 97% less air pollution during the Marathon than the other Sundays measurements were taken.

Not all cities around the world are struggling with air pollution, however.

Tallinn, Estonia

Data collected by the AQI for the Estonian Capital shows that air pollution is not a huge problem. Measurements recorded yesterday put Tallinn barely above the safe annual limit for PM10 and other air pollutants. The eastern European city regularly features in lists of cities with the cleanest air in the world, so what are they doing right?

The city of Tallinn holds one big advantage over many cities around the world when it comes to keeping air pollution levels low. When the old city was designed, cars were still hundreds of years from creation. Tight streets and narrow roads limit car access to many parts of the city meaning alternative forms of transport can thrive. However, it would be unfair to attribute the successes of Tallinn to its urban design alone.


The old city streets of Tallinn makes it difficult for cars to move around


For those who register with the Tallinn Municipality, a network of buses, trams and trolley-buses are available to use for free. For all others then a flat rate (that isn’t overly expensive) is offered. Giving residents a free transport option encourages many to leave the car at home, dramatically reducing air pollution in the city.

Zurich, Switzerland

Another city that is tackling harmful air pollution is the Swiss city of Zurich.

In terms of its urban design, Zurich is a much similar match to London and many other UK cities. Whilst we continue to struggle reducing air pollution, Zurich seems to have identified the problem and found ways to tackle it.

As I’ve mentioned already, car use in our cities has a huge impact on air pollution. So that’s exactly where Zurich has started. The city has capped the number of parking spaces in the city meaning that only so many cars can travel in to and park in the city.


Zurich is taking cars off the road and becoming a cleaner and healthier city!


Zurich is also limiting the areas where cars can drive around the city. An increasing number of areas are becoming car-free or entirely pedestrianised in order to further discourage the use of cars in the city. By reducing the benefits of car use, people are discouraged to use them and will choose other forms instead.

And they’re not the only city targetting car use to reduce air pollution. More people in Copenhagen, Denmark, and Amsterdam, The Netherlands, are using bikes to travel around. In both cities, there are now more bicycles than people!

Learning from Others

Cities around the world are slowly beginning to tackle the problem of air pollution, but in the UK we’re still a long way behind. Excessive car use continues to choke our urban areas but alternatives that are much cleaner and cost-effective are limited. Cities around the world are finding ways to deal with it, so there is absolutely no reason why we in the UK can’t.

So if you are out and about on this Clean Air Day, consider getting around on a different, cleaner mode of transport. Whether that’s public transport, the bike that’s been gathering dust in storage, or even walking! Every journey not taken in a car has a huge impact and there is no better day than Clean Air Day to consider the impact we all have on air pollution.





One thought on “Why are we still Struggling with Air Pollution?

  1. A recent study found that young Londoners could have over a billion toxic particles in their hearts!! It is crucial that we solve this, whether it’s by looking at how other cities are designed or adopting new tech (electric cars).

Leave a Reply