Air pollution is one of the biggest silent killers in the world, taking the lives of 19,000 people every day – more than HIV/AIDS, tuberculosis, malaria and car accidents combined. Why have we got to this stage and what can be done about it? Sustainability journalist Tim Smedley travelled around the world, gleaming insights from scientists, politicians and people affected, to find out. Read on to find out about what he’s discovered.

Clearing the Air, published by Bloomsbury Sigma, is out now

When did you realise air pollution and the air we breathe was a serious issue?

It was 2014, I had just become a father, and a headline in the Evening Standard caught my eye: “Boris Johnson accepts scientists' claims Oxford Street has worst diesel pollution on Earth.” This came as something of a surprise to say the least: the shopping street where I had taken my daughter to pick out her first pram had some of the most polluted air in the world?! Where were the health warnings, the public information signs, the protesters marching? All I could see were happy, oblivious shoppers (like myself). Weeks later came another headline: ‘Oxford Street pollution levels breached EU annual limit just five days into 2015’. Then the smog in Beijing became so bad that it was dubbed the ‘Airpocalypse’. The toxic smog in Delhi began to make international headlines, too. Many of the questions I was asking were being asked by many others too: what is air pollution? Where does it come from? And what can we do about it? As I searched for the answers, I started to write a book about it – and that book became Clearing the Air.

What are the implications for our health?

There are so, so many. In the book I describe it as the ‘life course of air pollution’, because it affects us at every stage of life, from reduced lung capacity in children, to cancers in adults, and dementia in the elderly. While asthma and lung disease are most commonly linked with air pollution, in fact cardiovascular disease is the biggest killer. The very smallest particles (known as nanoparticles) can pass through the lungs and into our blood stream, where they can raise blood pressure and cause blockages, leading to strokes and heart attacks. Cumulatively, this is reducing our quality of life and our life expectancy. A recent paper in the European Heart Journal estimates that life expectancy in Europe is reduced by about 2.2 years in Europe (1.5 years in the UK, and 2.8 year in Poland where coal is still king). Putting all these premature deaths together, in 2018 the World Health Organisation (WHO) announced that outdoor air pollution caused over 4.2 million deaths worldwide. More recently however, two separate papers in major international health journals suggest annual deaths from outdoor air pollution reach 8.79 million and 8.9 million, respectively. This is double the WHO estimate, and higher even than annual deaths from smoking (7.2 million). Smoking, however, is a choice – breathing in pollution is not.

Air pollution is responsible for thousands of deaths on a daily basis

What surprised you most during your research?

I could talk about the time I landed in Delhi shortly after a smog that was so bad the street dogs were dying from it. Or the study that found the lungs of children in London had been permanently stunted, thanks to traffic fumes. But in terms of the sheer callous disregard for health, I think that ‘award’ must go to shipping. For the last 30 years or so most cargo ships have been burning residual fuel, the very dregs from the oil-refining process (memorably described to me during my research for the book as being ‘like tarmac’). The oil industry was very keen for the shipping industry to use residual fuel because they had nothing else they could do with it. A mid-size cruise ship can burn through 150 tonnes of this stuff each day, emitting as much particulate matter as one million cars, as much NOx as 421,000 cars, and the sulphur emissions of 376 million cars (yes, you read that right). 

How can we make a difference?

Here’s the good news – we have the solutions to air pollution. Unlike climate change there is no ‘2 degrees’ scenario, no knowledge that suggests ‘things are going to get worse whatever we do’. Urban air pollution is local, short-lived, and can be stopped at the source. Last month (March, 2019) I visited the Hackney ‘School Streets’ initiative – a temporary closure of roads around five local schools at drop off and pick up times. The difference it makes to both children’s exposure to pollution and to the mood and stress levels of the parents is dramatic. A recent Public Health England review of air quality interventions has called for more such ‘spatial zoning’, and to make walking and cycling easier, as a top priority. They also call for councils to introduce no-idling zones outside hospitals, more low emission zones, and infrastructure for electric cars. Building green walls of plants and trees makes a big difference too – planting vegetation in cities can reduce street-level concentrations of NO2 by 40% and particulate matter by 60%. Cleaner air leads to a healthier, happier, economically more productive world. My hope is that Clearing the Air can inspire people to achieve this in their city, town or village too.

A snippet of the global scale of the problem

Clearing the Air: the Beginning and the End of Air Pollution, by Tim Smedley, is published by Bloomsbury Sigma and available to buy here.