London: Air pollution “pandemic” is shortening people’s lives worldwide by an average of nearly three years, says a study which suggests that the deadly impact of dirty air is far greater than wars and other forms of violence, parasitic and vector-borne diseases such as malaria, HIV/AIDS and smoking.
The research showed that air pollution had a greater effect on shortening lives in older people, with the exception of deaths in children aged under five in low income countries, such as Africa and South Asia.
Globally, about 75 per cent of deaths attributed to air pollution occur in people aged over 60 years, according to the study published in the journal Cardiovascular Research.
“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’,” said Thomas Munzel of University Medical Centre of the Johannes Gutenberg University in Mainz, Germany.
Using a new method of modelling the effects of various sources of air pollution on death rates, the researchers estimated that globally air pollution caused an extra 8.8 million premature deaths a year in 2015.
This represents an average shortening of life expectancy of nearly three years for all persons worldwide.
In comparison, tobacco smoking shortens life expectancy by an average of 2.2 years (7.2 million deaths), HIV/AIDS by 0.7 years (1 million deaths), diseases like malaria that are carried by parasites or insects such as mosquitoes, ticks and fleas by 0.6 years (600,000 deaths), and all forms of violence (including deaths in wars) by 0.3 years (530,000 deaths).
“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,” said Professor Jos Lelieveld from the Cyprus Institute Nicosia, Cyprus.
“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 9, alcohol by a factor of 45, and drug abuse by a factor of 60,” Lelieveld said.
The researchers looked at the effect of air pollution on six categories of disease: lower respiratory tract infection, chronic obstructive pulmonary disease, lung cancer, heart disease, cerebrovascular disease leading to stroke, and other, non-communicable diseases, which include conditions such as high blood pressure and diabetes.
They found that cardiovascular diseases (heart disease and cerebrovascular disease combined) are responsible for the greatest proportion of shortened lives from air pollution: 43 per cent of the loss in life expectancy worldwide.
The researchers estimate that if air pollution was reduced by removing fossil fuel emissions, the average life expectancy worldwide would increase by just over a year, and by nearly two years if all human-made emissions were removed.
However, there are large differences between regions due to the diversity in emissions.
In East Asia, which has the highest loss of life expectancy due to avoidable air pollution, three of the average of four years of lost life expectancy could be prevented by the removal of human-made emissions.
In Africa, where population growth is rapid and pollution from dust predominates, only 0.7 of 3.1 years lost could be prevented.
In Europe, there is an average of 2.2 years of lost life expectancy, 1.7 of which could be prevented, and 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, said the study.
“When we looked at how pollution played a role in several diseases, its effect on cardiovascular disease was by far the largest — very similar to the effect of smoking. 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,” Lelieveld added.
