A new study has shown that when air pollution improved in Stockholm, children’s lung health improved.
Researchers from Karolinska Institutet have discovered that when air pollution decreased, lung health and capacity of children and adolescents improved. They consider the results important since establishing good lung health in the young affects the risk of chronic lung diseases as they age.
“Fortunately, we’ve seen a decrease in air pollutants and therefore, an increase in air quality in Stockholm over the past 20 years,” commented the study’s last author Erik Melén, paediatrician and professor at the Department of Clinical Research and Education, Karolinska Institutet. “We therefore also wanted to examine if the lungs of children also improved during this period.”
The research is published in the European Respiratory Journal.
The impact of air quality on lung health
The impact of airborne pollutants on children’s lung health is well-recorded. The researchers noted that changes in air quality and the effect on lung development in children and adolescents are less studied.
The team used data from the BAMSE project which followed 4,000 individuals born between 1994 and 1996. All the children were given a questionnaire to answer and spirometry examinations to test their lung function at eight, 16 and 24 years old.
The researchers estimated concentrations of airborne pollutants, mostly attributed to traffic, at sites where the participants lived from birth until early childhood.
Generally, air pollution levels were 40% lower in Stockholm between 2016 and 2019 than it was between 2002 and 2004. However, in some locations, such as Hornsgatan on Södermalm, it had decreased by 60%, and in others, there was no significant difference in air quality.
“When we compare the individuals living in the areas in which air quality has improved and those in which it hasn’t, we find that lung function improved by a few per cent in the participants in the young adult age bracket,” said the study’s first author Zhebin Yu, postdoc researcher at the Institute of Environmental Medicine, Karolinska Institutet. “But above all, we could see a 20% lower risk of having significantly impaired lung function.”
Low exposure led to better lung function in early adulthood
The researchers conclude that lower exposure to airborne pollutants, even at low levels, is associated with improvements in the development of lung function from childhood to early adulthood.
The results are important, said Professor Melén, since optimal lung development during childhood is a powerful determinant of good health in adulthood.
“It is ultimately of great importance since the lung function that children and adolescents develop as they grow up persists into adulthood,” he explained. “If you have reduced lung function as an adult, you run a greater risk of chronic lung diseases like COPD, cardiovascular disease and premature death. So, by improving air quality, we reduce the likelihood of children developing chronic diseases later in life.”
Previous studies from the BAMSE project have shown that lung function growth can both improve and deteriorate over time, and these new results show the important role that air pollution plays in this.
“Airborne pollutants that are by nature persistent are a great worry, and our study clearly indicates that efforts to improve air quality have paid off, with quantifiable improvements in child and adolescent health,” said Professor Melén.
The researchers are planning to examine potential advantages of cleaner air for lung diseases like asthma, bronchitis and prodromal COPD and cardiometabolic diseases, such as cardiovascular disease and type 2 diabetes.
