Air pollution is reducing global life expectancy by three years, scientists find

Air pollution is reducing global life expectancy by three years, killing 8.8million people a year, a study shows.

More people are dying early from breathing toxic air than some of the largest killers, including malaria, HIV, war and smoking.

Scientists led by Germany fear the world is facing an air pollution ‘pandemic’ after analysing deaths in every country.  

Life expectancy has been cut short in East Asia, including countries such as Japan and India, by almost four years, and 2.2 years in Europe.  

Long-term exposure to air pollutants was found to predominantly kill by affecting the heart and blood vessels which supply the brain.  

Around two-thirds of deaths are deemed avoidable because they were attributable to human-made pollution, such as from fossil fuels.

The international team of authors, led by Professor Jos Lelieveld of Max Planck Institute for Chemistry, Mainz, examined the relationship between air pollution exposure and people’s ‘loss of life expectancy’.

Computer models were able to calculate that life expectancy across the world has been reduced by 2.9 years, or two years and ten months. 

By comparison, tobacco smoking shortens life expectancy by an average of 2.2 years, and HIV/Aids by 0.7 years.

Diseases like malaria that are carried by parasites or insects such as mosquitoes shortens lives by 0.6 years, and all forms of violence – including deaths in wars – by 0.3 years. 

Using new modelling techniques, the authors estimated that globally, air pollution caused an extra 8.8million premature deaths in 2015.

Tobacco kills some 7.2million people a year, HIV/AIDS one million, malaria 600,000 and violence 530,000.

Air pollution had a greater effect on shortening lives in older people – globally, about 75 per cent of deaths attributed to air pollution occur in people aged over 60 years.

Writing in their new paper, published in the journal Cardiovascular Research, the authors said that ambient air pollution is one of the ‘main global health risks’.  

Professor Lelieveld said: ‘It is remarkable that both the number of deaths and the loss in life expectancy from air pollution rival the effect of tobacco smoking and are much higher than other causes of death.

‘Air pollution exceeds malaria as a global cause of premature death by a factor of 19; it exceeds violence by a factor of 16, HIV/Aids by a factor of nine, alcohol by a factor of 45, and drug abuse by a factor of 60.’ 

Co-author Professor Thomas Münzel said: ‘Since the impact of air pollution on public health overall is much larger than expected, and is a worldwide phenomenon, we believe our results show there is an “air pollution pandemic”.  

‘In this paper we distinguished between avoidable, human-made air pollution and pollution from natural sources such as desert dust and wildfire emissions, which cannot be avoided. 

‘We show that about two-thirds of premature deaths are attributable to human-made air pollution, mainly from fossil fuel use; this goes up to 80 per cent in high-income countries. Five and a half million deaths worldwide a year are potentially avoidable.’

The researchers suggested that without human-made emissions, global life expectancies would increase by nearly two years.

Without fossil fuels alone, life expectancy would increase by one year. 

However, there are large differences between regions due to the diversity in emissions. 

Despite Africa being one of the worst affected by air pollution, losing three years of life expectancy, only 0.7 years lost could be prevented. 

This is because Africa has mostly pollution from dust. By comparison, East Asia could prevent three of the average of four years of lost life expectancy lost by removing its main source of pollution – human-made emissions.

In Europe, there is an average of 2.2 years of lost life expectancy, 1.7 of which could be prevented. In North America there is an average of 1.4 years of lost life expectancy, of which 1.1 could be prevented, mostly by phasing out fossil fuels. 

Commenting on the findings, Dr Samuel Cai, a senior epidemiologist at University of Oxford, said: ‘This study once again shows that air pollution is a leading risk factor for health worldwide. It is not a secret that air pollution is the “new tobacco”.

‘I do not feel there is any overspeculation in the findings of this study as they are supported by the good science. It sounds like the word “pandemic” qualifies.’ 

The research looked at the effect of air pollution on six categories of disease.

They found that cardiovascular diseases – including of the heart and blood vessels to the brain – are responsible for the greatest proportion of shortened lives from air pollution, at 43 per cent of the loss in life expectancy worldwide.

Professor Lelieveld said it is important for air pollution to be added to ‘risk factors’ for heart and blood vessel disease along with smoking, diabetes and high blood pressure and cholesterol, in official guidelines. 

He said: ‘Air pollution causes damage to the blood vessels through increased oxidative stress, which then leads to increases in blood pressure, diabetes, stroke, heart attacks and heart failure.’

Jacob West, executive director of healthcare innovation at the British Heart Foundation (BHF), said: ‘This study presents further evidence that air pollution is a public health emergency that can worsen or shorten lives.

‘Up to 11,000 deaths due to a heart attack or stroke are associated with toxic air each year in the UK. Current legal limits do not go far enough to drive the improvements we need to the quality of our air.’ 

Professor Kevin McConway, emeritus professor of applied statistics, The Open University, said the findings were ‘statistically sound’.

However, he added: ‘I don’t think we can be confident that ambient air pollution kills more people than tobacco smoking. There is too much uncertainty about the exact numbers.

‘The comparison between air pollution and tobacco certainly doesn’t mean that it’s just as bad for you to go out into a street with high air pollution as it is to smoke some cigarettes.’