Study reveals a link between air pollution and child health
Studies have shown air pollution is a major risk factor for respiratory infection – the leading cause of death among children under five – but bad air’s specific impacts on developing bodies have remained somewhat of a mystery.
A Stanford-led study reveals a link between tiny airborne particles and child health in South Asia, a region beset with air pollution and more than 40 percent of global pneumonia cases. The analysis, published in Environmental Pollution, estimates the effect of increased particulate on child pneumonia hospitalizations is about twice as much as previously thought, and indicates a particular industry may play an outsized role in the problem.
The findings could help public health officials and policymakers better target emissions reduction programs to improve child health.
Everybody wants to protect kids’ health. Now, we have evidence of a clear health benefit to children from reducing ambient PM2.5 emissions in Dhaka.”
Allison Sherris, study lead author, postdoctoral research fellow in Earth system science at Stanford’s School of Earth, Energy & Environmental Sciences
For many of the 21 million residents of Dhaka, Bangladesh – the study’s focus area – air pollution is an all-too-regular part of life, especially in winter, when coal-burning brick kilns around the city operate. Of special concern is PM2.5, airborne particles 2.5 micrometers wide or smaller. The larger of these particles are about one-thirtieth the width of a human hair, small enough to inhale deep into the lungs.
Once inside the lungs, these particles can cause inflammation and impair the body’s ability to fight infection. But particles from different sources can have different shape, size and chemical composition, and it’s not clear what specific components of PM2.5 might be most harmful.
Few studies have evaluated the health effects of PM2.5 in infants and young children, especially in low-income countries where children are more than 60 times as likely to die from air pollution exposure as children in high-income countries, according to the World Bank. Among studies that have, most focused on the indoor environment, where the use of biomass-burning cookstoves has been associated with child respiratory infection.
“Specifying the impact of industry-generated air pollution on child health provides compelling evidence to support interventions to reduce pollution,” said study senior author Stephen Luby, a professor of infectious diseases at Stanford University. “This is often more salient to politicians than the marginal contribution of emissions to global climate change.”
Sherris, Luby and their colleagues analyzed long-term PM2.5 monitoring data alongside community health surveillance of respiratory infections from the Atomic Energy Centre, Dhaka, and the International Centre for Diarrhoeal Disease Research, Bangladesh. They found pneumonia incidence among children under 5 increased by 3.2 percent for every…