Air pollution not only affects lung health but also brain development in children, according to two studies presented at the World Conference on Lung Health (WCLH) held in Denmark recently.

One study from India found that children living in highly polluted areas scored nearly 20 points lower on the intelligence quotient (IQ) than their peers in cleaner environments, immediately limiting their educational potential and life opportunities.

These findings highlight air pollution as not merely an environmental issue but a global health emergency that threatens children’s futures and severely worsens existing lung disease.

Air quality lowers IQ in children

Zeroing in on the link between airborne particulate matter and cognitive ability, new findings from the Kalinga Institute of Industrial Technology (KIIT) in India suggest a significant and close association between children’s IQ development and long-term exposure to ambient air pollution.

The KIIT study, published in the WCLH abstract book, examined the impact of particulate matter PM2.5 and PM10 (particulate matter with a diameter of 2.5 and 10 micrometres) on the cognitive development of children aged 6-8 in the state of Odisha in India. While the effects of air pollution on lung and cardiovascular health are well documented, this research represents a pioneeringl look into its potential to disrupt cognitive development in children.

Setting up a comparative analytical study, researchers assessed two sites between July and December 2022: one with high pollution levels (PM10 above 60 micrograms per cubic metre and PM2.5 above 40 micrograms) and one with low pollution. Children who had lived within a 1.5 km radius of air quality monitoring stations for six years were tested, using Malin’s Intelligence Scale for Indian Children, which measures full-scale, verbal, and performance IQ.

The results were stark. Mean Full-Scale IQ in high-pollution areas was 80.33 compared to 98.12 in low-pollution areas. Children from high-pollution areas had a verbal IQ of 81.60 compared to 99.68 in low-pollution areas, and a performance IQ of 79.02 compared to 96.55 in cleaner areas.

The authors conclude that long-term exposure to air pollution is closely linked to poorer cognitive development in children. The report further suggested that the child’s age and weight, poor kitchen ventilation, maternal education, and family income also made an impact on full-scale IQ, painting a picture of multiple interacting risk factors.

Air pollution affects the poorest the most

“The burden of air pollution and climate change on health is one which sadly continues to grow. And, as with many other determinants of health, it is the world’s poorest who are the most affected,” said Professor Guy Marks, president of the International Union Against Tuberculosis and Lung Disease (The Union).

“New strategies are urgently needed globally to ensure no one’s future is limited simply because of the air they breathe.”

The Union was established in 1920 as the world’s first global health organisation and works towards a world free of tuberculosis and lung disease. Its members, staff, and consultants work in more than 140 countries globally. 

Asthma attacks increase in West Africa

Separately, a direct link between air pollution and the severity of asthmatic conditions in adolescents has been reported in a new study by the Centre Hospitalier et Universitaire de Pneumo-Phtisiologie (CNHUPPC) in Cotonou, Benin, in West Africa.

In Cotonou, where air pollution systematically exceeds World Health Organisation (WHO) thresholds for all pollutants, researchers followed a cohort of 730 asthmatic adolescents over 36 months. The study reported that over one-third 37% of the adolescents experienced at least one respiratory event or asthma attack.

Measuring individual exposure via portable air quality sensors carried in backpacks and fixed sensors in schools and homes, the researchers determined that the adolescents with frequent respiratory events had higher levels of exposure to several pollutants, including nitrogen dioxide, PM1, PM2.5 and PM10. 

The study also noted that asthma symptoms occurred 2.5 times more during the seasonal harmattan period when a cool, dry and dusty wind blows, usually between December and March. This highlights the compounding effect of climate-related atmospheric changes. 

“Fine particulate air pollution remains very high in West Africa and poses a serious risk to the respiratory health of adolescents with asthma who are chronically exposed,” said Dr Attannon Arnauld Fiogbé, chest physician and clinical researcher at CNHUPPC. He suggested that strengthening responses by combining air quality alerts with therapeutic education could significantly improve respiratory health.

Air purifiers in schools 

Proposing a tangible solution to mitigate some of the exposure, Professor Anant Sudarshan from the University of Warwick in the UK, advocates for targeted intervention in schools, especially for low-income communities. 

“Introducing appropriately sized air purifiers in all government schools may be a good policy. Children spend a significant share of their day in classrooms, and any reduction in pollution exposure can have large health benefits,” Sudarshan told Health Policy Watch. 

“This is most important for the poor who cannot afford to purify air at home or who live close to traffic or industry,” Sudarshan added.

Sudarshan explained that children spend roughly one-third of their day at school for two-thirds of the year – around 17% of their lives – so cleaning up the air just in schools could cut a child’s annual pollution exposure by approximately 17%.

This reduction is considered vital because PM2.5 has been shown to have similar effects on cognitive behaviour and productivity as CO2 buildup, impacting both short-term alertness and long-term development. 

For policymakers grappling with this crisis, the evidence is now clear: the fight for lung health must integrate immediate, robust action to protect the cognitive and life-long potential of the world’s children.

Image Credits: Akshar Dave/ Unsplash.