Air pollution is a bigger cause of premature death than smoking، killing an estimated 8.8 million people globally per year، a study has claimed، daily mail reported.
The research suggests that the deaths can be attributed to dirty particulate from vehicle exhaust pipes، factories and power plants.
A World Health Organisation estimate for 2015 says that tobacco smoking was responsible for an extra 7.2 million deaths a year.
In the UK، air pollution was thought to have caused 64،000 deaths in the UK the same year، including 17،000 fatal cases of heart and artery disease.
Co-author Professor Thomas Munzel، from the University Medical Centre Mainz in Germany، said: 'Smoking is avoidable، but air pollution is not.'
In Europe alone the researchers put the excess death toll figure at 790،000، twice the previous estimate.
More than 29،000 other British deaths linked to air pollution were due to a range of conditions such as cancer، diabetes and chronic lung disease.
The study involved computer simulations of interacting natural and man-made chemicals combined with information about population density، disease risk factors، and causes of death.
Average life expectancy was reduced by 1.5 years among people in the UK dying as a result of air pollution، according to the study.
However، Britons were not as badly affected as some of their European neighbours.
In Germany، air pollution was said to have been responsible for an extra 124،000 deaths in 2015 and 2.4 years of lost life expectancy.
During the same year an estimated 81،000 people were killed by air pollution in Italy، 67،000 in France and 58،000 in Poland.
Professor Munzel said that the number of deaths from cardiovascular disease that can be attributed to air pollution is much higher than expected.
'In Europe alone، the excess number of deaths is nearly 800،000 a year and each of these deaths represents an average reduction in life expectancy of more than two years.'
Worldwide، air pollution was found to account for 120 extra deaths per 100،000 people per year.
In Europe the picture was even worse with 133 per 100،000 deaths attributed to inhaled pollutant chemicals.
Cases of lung and cardiovascular disease were mainly caused by microscopic 'PM 2.5' particles that become lodged in lungs and enter the bloodstream، said the researchers.
Diesel road vehicles are one of the biggest producers of particulate pollution in developed countries such as the UK.
Other sources of the lethal particles include fossil fuel-burning industrial processes، power plants and domestic heating.
Co-author Professor Jos Lelieveld، from the Max-Planck Institute for Chemistry in Mainz، said: 'The high number of extra deaths caused by air pollution in Europe is explained by the combination of poor air quality and dense population، which leads to exposure that is among the highest in the world.'
Writing in the European Heart Journal، the scientists called for more stringent curbs on particulate pollution.
Currently the average safety limit for PM2.5 particles in the European Union is 25 micrograms per cubic metre of air.
This is more than double the WHO recommendation of 10 micrograms.
'Many other countries، such as Canada، the USA and Australia، use the WHO guideline،' said Professor Munzel. 'The EU is lagging a long way behind in this respect.'
WHAT ARE THE HARMFUL EFFECTS OF VEHICLE EXHAUST? The excess emissions of harmful nitrogen oxide (NOx) exhaust gases can be linked to 38،000 premature deaths worldwide، according to the new research.
NOx can damage lung tissue but also reacts with chemicals in the atmosphere to produce ground-level ozone and ultra-fine particles، both of which are harmful.
Ozone irritates the airways and aggravates lung diseases such as asthma and bronchitis، while inhaling fine particles is strongly linked to heart and artery disease.
The study، published in the journal Nature، found that diesel vehicles around the world produced 4.5 million tons more NOx than they should do under international emission standards.
WHAT IS THE AIR QUALITY INDEX? The Air Quality Index (AQI) is a measure used by environmental agencies and other public bodies around the world to measure how clean the air is.
The lower the index is، the better the quality of the air.
The AQI provides a number which is easy to compare between different pollutants، locations، and time periods.
Exactly how this score is categorised varies from country to country، but each category in the AQI corresponds to a different level of health risk.
The daily results of the index are used to convey to the public an estimate of air pollution level.
An increase in air quality index signifies increased air pollution and severe threats to human health.
The AQI centres on the health effects that may be experienced within a few days or hours after breathing polluted air.
AQI calculations focus on major air pollutants including: particulate matter، ground-level ozone، sulfur dioxide، nitrogen dioxide، and carbon monoxide.
Particulate matter and ozone pollutants pose the highest risks to human health and the environment.
For each of these air pollutant categories، different countries have their own established air quality indices in relation to other nationally set air quality standards for public health protection.