The evidence from these studies is unequivocal, researchers point out: air pollution is a direct threat to children’s intellectual growth, disproportionately affecting the vulnerable.

Researchers have found that young children exposed to high levels of airborne pollutants in the state of Odisha scored nearly 20 points lower on IQ tests compared to their peers in cleaner areas. This drop not only hampers immediate educational outcomes but also casts a long shadow over lifelong opportunities, turning what was once seen as an environmental nuisance into a profound public health crisis.

Presented at the World Conference on Lung Health (WCLH) held in Denmark in November, these findings underscore that air pollution’s reach extends far beyond respiratory issues. It infiltrates brain development, potentially robbing generations of their full intellectual capacity.

Experts warn that without urgent interventions, this could exacerbate social inequalities, as the poorest communities bear the brunt of polluted air. The studies highlight air pollution as a global health emergency, demanding immediate action to safeguard children’s futures and mitigate its role in worsening lung diseases.

Air Quality Lowers IQ in Children

Delving deeper into the connection between particulate matter and cognitive growth, the groundbreaking study from the Kalinga Institute of Industrial Technology (KIIT) in India has illuminated the severe impacts of long-term exposure. Published in the WCLH abstract book, the research focused on children aged 6-8 in Odisha, comparing those in highly polluted zones – where PM10 levels exceeded 60 micrograms per cubic meter and PM2.5 surpassed 40 micrograms – with counterparts in low-pollution environments.

The methodology was rigorous: participants had resided within a 1.5-kilometer radius of air quality monitoring stations for at least six years, ensuring chronic exposure was accurately captured. Using Malin’s Intelligence Scale for Indian Children, the team measured full-scale, verbal, and performance IQ. The results painted a grim picture. In high-pollution areas, the mean full-scale IQ was 80.33, starkly lower than the 98.12 recorded in cleaner zones. Verbal IQ averaged 81.60 versus 99.68, while performance IQ stood at 79.02 compared to 96.55.

These disparities suggest that pollutants like PM2.5 and PM10 may interfere with neural pathways during critical developmental windows, leading to impaired cognitive functions. The study also identified compounding factors, including the child’s age and weight, inadequate kitchen ventilation, lower maternal education, and reduced family income, which interacted with pollution to further depress IQ scores. This multifaceted view reveals how environmental hazards amplify socioeconomic vulnerabilities, creating a cycle of disadvantage.

Professor Guy Marks, president of the International Union Against Tuberculosis and Lung Disease, emphasised the inequity: “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.” Marks called for innovative strategies to prevent air quality from dictating life outcomes.

Air Purifiers in Schools: A Practical Solution

Amid these alarming insights, experts are proposing actionable measures to curb exposure, particularly in educational settings where children spend much of their time. Professor Anant Sudarshan from the University of Warwick in the UK advocates for installing air purifiers in government schools, especially in low-income areas.

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

He highlighted that this is crucial for impoverished families who lack resources to purify air at home or who reside near heavy traffic or industrial sites. Children typically spend about one-third of their day at school for two-thirds of the year – equating to roughly 17 per cent of their overall lives. By purifying school air alone, annual pollution exposure could drop by approximately 17 per cent, yielding substantial cognitive and health gains.

Sudarshan drew parallels between PM2.5’s effects and those of CO2 accumulation, noting both impair short-term alertness and long-term brain development. This intervention could serve as a targeted, cost-effective step for policymakers, bridging the gap until broader air quality improvements are achieved.

The evidence from the study is unequivocal, researchers point out: air pollution is a direct threat to children’s intellectual growth, disproportionately affecting the vulnerable. As global leaders grapple with this crisis, integrating robust protections for lung and brain health is essential. Failure to act risks condemning millions to diminished potentials, underscoring the need for policies that prioritise clean air as a fundamental right, experts say.

Image: World Bank