A landmark European study has found that people living in built-up areas with limited green space, high levels of pollution, and exposure to artificial light at night face a significantly higher risk of developing asthma.
The findings come from EXPANSE, a major EU-funded project that analysed data from 14 population cohorts across Europe. Researchers studied over 349,000 individuals and identified around 7,400 new asthma cases.
What sets this study apart is its focus on the combined impact of multiple environmental stressors, rather than looking at each in isolation. While individual factors like air pollution or artificial light showed only modest links to asthma, the risk became much clearer when these exposures were assessed together.
“This provides a better picture of environmental risks, as life in a city usually involves exposure to several environmental factors at the same time,” said Zhebin Yu, lead author and assistant professor at the Karolinska Institute in Sweden, which led the research.
Other key findings include:
- Large-scale study: Over 349,000 people across 14 European cohorts were studied; approximately 7,400 new asthma cases were identified.
- Urban environments pose higher risk: People living in densely built areas with little greenery were more likely to develop asthma.
- Air pollution is a key contributor: Higher levels of particulate matter (PM) and nitrogen dioxide (NO₂) were linked to increased asthma risk.
- Cumulative risk is measurable: Researchers created a combined “environmental risk score” — the higher the score, the higher the likelihood of asthma. About 1 in 9 asthma cases could be attributed to poor environmental conditions.
- Women more vulnerable: The study found women to be more sensitive to environmental asthma risks than men.
- Long-term exposure matters: People who had lived at the same address for a long time showed stronger environmental associations with asthma.
- Call to action for urban planners: Findings support the need for city-specific planning strategies to reduce pollution, preserve green space, and prevent excessive urban density.
What does this mean for buildings design and healthy buildings?
Increasingly, more research is being presented regarding the impact of the built environment, and buildings in particular, on our health. But, how do we change structures that already exist? How do we improve the design of new buildings?
Given the variables tested in the experiment, there are practical steps that can be taken in the short term to improve health conditions:
- Incorporate biophilic design. Biophilic design incorporates various aspects of nature into the spaces we create. But this isn’t limited to simply adding a few plants to your office space. There are 15 key patterns in biophilic design that includes integrating natural materials such as wood and stone, simulating patterns and spaces that occur in nature, and even creating a sense of awe in your environment.
- Assess the lighting in your building. What can you do to help mimic natural lighting patterns during the day to support circadian rhythms? Research shows that lighting for different times of day helps people to feel better and boost health, thereby improving the experience of your employees.
- Check that your air filters are up to date. We spend 90% of our time indoors. Our buildings need to be filtering and ventilating air accordingly. Prioritising clean air can help improve workplace productivity and boost wellbeing.
To reach the full report, visit The Lancet.
Sophie Crossley
Sophie Crossley is our Content Editor. She has 5+ years of experience in comms with a focus on wellbeing, the built environment, and lifestyle.
