Research has found that air pollution is slowing the growth of British children’s lungs. Scientists tracked the lung function of more than 5,000 people born in and around Bristol in the 1990s. Their health was assessed from birth, their lungs tested as they grew between ages 8 and 15, and then at age 24, when they should have reached their peak lung function as adults.
Professor Anna Hansell from the University of Leicester, who led the research, said: ‘While much of the evidence on the health effects of air pollution concerns adults or pregnancy, we think it is very likely that air pollution affects the growth and development of children.
“People whose lungs did not grow to their fullest potential during childhood may be more susceptible to respiratory disease later in life because they have less spare capacity. They are also more likely to have poor health in general. For example, poor lung function in adults is associated with the same level of risk for heart disease as high cholesterol. Research also shows that people whose lung health is affected by air pollution may be at higher risk for heart disease.”
Dr Katie Eminson, also from the University of Leicester and lead author of the study, said: “Lung function was measured using spirometry by a trained technician. Participants were asked to take a deep breath and then exhale into a mouthpiece as hard and fast as possible. The machine measured both the amount of air they could exhale and the rate at which they breathed out, providing an indication of how well their lungs were working.”
The researchers calculated the children’s air pollution exposure during each trimester of pregnancy and each year of childhood. This includes nitrogen dioxide, a gas primarily produced by diesel cars and fossil gas boilers, but also particulate pollution.
Mr Hansell said: “We have literally spent years developing particulate air pollution exposure estimates during pregnancy and childhood, including obtaining road traffic data from Bristol City Council that is not available in national databases.”
The researchers also took into account other factors that could affect the child’s health, such as premature birth, breastfeeding, parental smoking, and home environment such as humidity.
Researchers have found that breathing in a lot of air pollution during pregnancy, infancy, and early childhood can slow lung development into early adulthood. The biggest impact is during adolescence, when lung growth accelerates.
Previous research has found that air pollution reduces lung growth in children in east London. Here, the average 9-year-old’s lungs were 90 to 100 milliliters smaller than they should be. This is equivalent to the volume of about 2 chicken eggs.
A study of Swedish children showed that improved air quality increased lung growth. Reduced air pollution may also have allowed the lungs of children in Bristol to grow closer to normal rates.
Professor Eminson concluded: “Although the effects on individual children are small and unlikely to have immediate clinical consequences, they should not be ignored. Lung function tends to be tracked from childhood into adulthood, so small differences early in life can impact long-term health. This reinforces the importance of reducing exposure and protecting children’s environments.”
