Written By Anuradha Varanasi 

Globally, children and adolescents have being growing up in areas with high levels of air pollution since the Industrial Revolution took off. According to the World Health Organization, more than 90% of the world’s children below the age of 15 breathe air with such high levels of air pollution that it puts them at a severe risk of developing chronic diseases. But since the last three decades or so, developed countries have not only identified, but also gotten rid of several air pollutants after implementing stringent regulations on vehicle emissions and industries. This has given scientists the opportunity to study how cleaner air is benefitting children, who are the most vulnerable to air pollution exposure as their lungs are still developing.

In a recent study, a group of Sweden-based researchers found that in Stockholm, as air pollution levels started declining since the early 2000s, children and adolescents had improved lung capacity. One of the study’s authors, Erik Melén, who is a paediatrician and professor at Karolinska Institutet said, “Fortunately, we’ve seen a decrease in air pollutants and therefore an increase in air quality in Stockholm over the past 20 years. 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.”

Published in the European Respiratory Journal, the researchers analyzed data of 4000 people who were born within a two year span from 1994 to 1996. Each one of them answered questionnaires and underwent spirometric examinations to determine how their lungs were functioning when they were 8, 16, and 24 years old. The researchers then compared those time periods to the levels of estimated air pollutants from vehicles emissions at the locations where the participants resided.

Compared to 2002 and 2004, in Stockholm, air pollution levels were far lower from 2016 to 2019 ranging from 40% to 60% lesser air pollutants in the lower atmosphere. “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 Zhebin Yu, the lead author of the study who is a researcher at Karolinska Institutet’s Institute of Environmental Medicine, in a press release. “But above all we could see a 20 per cent lower risk of having significantly impaired lung function.”

According to the American Lung Association, 80% of a person’s air sacs start developing after birth. These sacs are solely responsible for transferring oxygen to the blood. Children also breathe twice as fast as adults and take in more air for each unit of their body weight. Because their immune systems are still developing, they are more vulnerable to air-borne bacilli and viruses. Previous studies have found that the lung capacity of children who are exposed to high levels of air pollution from birth is 20% lower than those whole live in areas with clean air. That also puts them at a far higher risk of developing asthma and other respiratory problems later in life. At present, Asia accounts for the highest number of deaths that could be attributed to air pollution, as per a UNICEF report.

“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,” added Melén. “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.”