Alphagalileo > Item Display

Cleaner air has increased life expectancy by up to 1 year

The residents of Stockholm, Gothenburg and Malmö live one year longer today than 25 years ago. The reason is that the levels of air pollutants from road traffic have fallen. This is shown in a new study published in the discussion forum of the scientific journal Atmospheric Chemistry and Physics by researchers at the Department of Environmental Sciences and Analytical Chemistry (ACES).

The research group has used results from measurement stations centrally located in each city: In Stockholm, the instruments are placed on a roof at Torkel Knutssongatan at Södermalm, in Gothenburg on a roof in Östra Nordstan and in Malmö on the roof of the City Hall. The measurements have included nitrogen oxides, ozone and particles in the air from 1990 to 2015. Now scientists can draw certain conclusions about the causes of changes in levels over time and what health effects this gives for the residents of the three cities:

In the case of nitrogen oxides, concentrations have fallen noticeably in all three cities, but the levels of ozone have risen somewhat, and for particles, the measurements show slightly different results for the three cities.

“Overall, this means that the air quality has improved in all three cities, which has led to improved public health, and it is estimated that life expectancy has increased by up to one year. This is mainly due to reduced levels of exhaust emissions from road traffic”, says Henrik Olstrup, PhD student in atmospheric science at ACES.

Nitrogen oxides are mainly produced by combustion processes in engines and, in large part, the reduction of nitrogen oxides in the air can be explained by stricter rules for new vehicles in terms of exhaust emissions, researchers say. Nitrogen oxides are indicators of combustion-related air pollutants from traffic. The health benefits that have taken place are unlikely to be linked only to reduced nitrogen oxides, but rather a result of a general reduction of exhaust emissions, involving a wide range of gases and combustion-related particles.

In both Stockholm and Malmö, the amount of nitrogen oxides in the air has fallen from about 40 micrograms per cubic meter in 1990 to about 20 micrograms per cubic meter in 2015. In Gothenburg, the levels of nitrogen oxides in the air have fallen from about 60 micrograms per cubic meter in 1990 to about 40 micrograms per cubic meters in 2015, so the decrease has been about the same in all three cities, although the overall levels are higher in Gothenburg. The reason for the higher levels of nitrogen oxides in Gothenburg can be the several highways through the city and also the presence of major motorways close to the city.

The fact that the ozone content has risen slightly during the measurement period, the researchers believe is largely due to the decrease of nitrogen monoxide, which reduces the importance of photochemical reactions with ozone, so that higher ozone concentrations can be built up.

“But the higher ozone levels give a relatively small effect on health, as opposed to reduced exhaust gas exposure. And for coarse particles, which mainly arise through road wear from studded  tires, there are no clear changes in the levels during the period 1990-2015, which means that the impact on the expected life expectancy becomes insignificant”, says Henrik Olstrup.

The calculations of how life expectancy is affected by air pollution are based on previous studies of exposure to air pollution and mortality, and partly on statistics on, among other things, population size and age structure. The calculations have also taken into consideration how the levels vary across the cities and where people live.

That air pollution exposure can shorten life and make people sick has been known for a long time.

“The average life expectancy in the three cities has increased by approximately 4-5 years from 1990 to 2015. Significant causes for this increase include, among other things, more effective treatment methods for cardiovascular diseases and reduced smoking among the population. The reduced air pollution exposure is expected to contribute up to 20 percent of this increase, which can be considered as a very significant effect. It shows that emission control measures can give major health benefits”, says Henrik Olstrup.

The article “Trends in air pollutants and health impacts in three Swedish cities over the past three decades” is published in the discussion forum of the scientific journal Atmospheric Chemistry and Physics.
Attached files
  • Hornsgatan%20Foto%20Astrid%20Va%CC%8Agen%20Wikimedia%20Commons.jpg
Keywords: Health, Environmental health, Policy, Science, Environment - science


For well over a decade, in my capacity as a researcher, broadcaster, and producer, I have relied heavily on Alphagalileo.
All of my work trips have been planned around stories that I've found on this site.
The under embargo section allows us to plan ahead and the news releases enable us to find key experts.
Going through the tailored daily updates is the best way to start the day. It's such a critical service for me and many of my colleagues.
Koula Bouloukos, Senior manager, Editorial & Production Underknown
We have used AlphaGalileo since its foundation but frankly we need it more than ever now to ensure our research news is heard across Europe, Asia and North America. As one of the UK’s leading research universities we want to continue to work with other outstanding researchers in Europe. AlphaGalileo helps us to continue to bring our research story to them and the rest of the world.
Peter Dunn, Director of Press and Media Relations at the University of Warwick
AlphaGalileo has helped us more than double our reach at SciDev.Net. The service has enabled our journalists around the world to reach the mainstream media with articles about the impact of science on people in low- and middle-income countries, leading to big increases in the number of SciDev.Net articles that have been republished.
Ben Deighton, SciDevNet

We Work Closely With...

  • BBC
  • The Times
  • National Geographic
  • The University of Edinburgh
  • University of Cambridge
Copyright 2021 by DNN Corp Terms Of Use Privacy Statement