2 million cases linked to automobile pollution in large cities

THE ESSENTIAL

• In children, asthma is the most common chronic disease and the leading cause of school absenteeism. In France, at least 10% of children suffer from it.
• Two million new cases of childhood asthma are caused by nitrogen dioxide air pollution generated by automobile traffic.
• Improvements in air quality have been observed in Europe and the United States over the years.

Prematurity, bronchiolitis, history of allergy … Several factors can promote the onset of pediatric asthma. A study, published in the journal The Lancet Planetary Health January 1, 2022, highlighted another cause of this chronic respiratory disease in children. This is nitrogen dioxide pollution created by automobile traffic in large cities.

“We have sought to estimate the global emissions of nitrogen dioxide (NO2)”, a pollutant emitted by car exhaust pipes, “as well as trends in concentrations and incidence on pediatric asthma in 13,189 cities from 2000 to 2019”, the research authors said. For the purposes of the work, they analyzed data on annual concentrations of nitrogen dioxide from a satellite observation of the presence of this substance to the nearest kilometer. The NO2 levels were crossed with the number of new cases of asthma in children identified each year between 2000 and 2019.

Areas most affected by nitrogen dioxide air pollution

“We estimated that 1.85 million new cases of pediatric asthma worldwide were attributable to NO2 in 2019, of which two-thirds were in urban areas,” scientists have reported. According to the results, the rates of cases of asthma in children attributable to nitrogen dioxide fell from 20% in 2000 to 16% in 2019. The territories most affected by the deterioration in the quality of air are South Asia (+ 23% for the rate of nitrogen dioxide pollution), sub-Saharan Africa (+ 11%) and the Middle East (+ 5%). In contrast, air quality has improved in Europe and the United States.

“Despite improvements in some regions, road traffic-related NO2 pollution continues to have a significant impact on pediatric asthma worldwide, particularly in cities. Improving air pollution should be a critical component of public health strategies for children “, the researchers concluded.