Air Pollution Is Harming Children’s Eyes – A New Study Reveals the Link

Children are particularly sensitive to air pollution. Air pollutants such as nitrogen dioxide (NO₂) and fine particulate matter (PM2.5) can impair vision, especially in younger children. Image: AI Generated

Myopia, or nearsightedness, is on the rise worldwide, particularly among children living in urban areas across East Asia. While genetics, screen time, and lack of outdoor activity have long been cited as key risk factors, a new and often overlooked element is now drawing attention: air pollution.

A large-scale study from China, published in the Proceedings of the National Academy of Sciences (PNAS), offers new evidence that pollutants in the air may have a direct impact on children’s vision. Researchers analyzed data from nearly 30,000 schoolchildren in the city of Tianjin and found a clear pattern: Better air quality is associated with better uncorrected visual acuity. In other words: clearer vision without glasses or contact lenses.

Machine Learning Uncovers a Hidden Risk

What sets this study apart is not just its size but also its method. Instead of using traditional statistical analysis, the researchers employed AutoML,  an automated machine learning model capable of recognizing complex patterns in large datasets. The model incorporated a broad range of variables, including genetic predisposition (such as whether the parents were myopic), time spent outdoors, screen time, academic pressure, local green space, and exposure to fine particulate matter (PM2.5) and nitrogen dioxide (NO₂).

The results were striking. Children who were exposed to cleaner air had measurably better eyesight. The effect was particularly strong in younger children and those with mild or moderate myopia. In older students or those with more severe vision problems, the impact of environmental factors was less pronounced – suggesting that early prevention is key.

How Polluted Air Affects the Eyes

There are several biological explanations for why air pollution might harm children’s vision. Nitrogen dioxide can cause inflammation on the surface of the eye. Fine particulate matter leads to oxidative stress, a process in which harmful molecules attack healthy cells. Together, these effects can interfere with the normal development of the eyeball and retina.

Additionally, polluted air reduces the quality of natural light outdoors and natural light is essential for regulating eye growth and preventing myopia. In young children, whose visual systems are still developing, this disruption can have lasting consequences. At the same time, their eyes remain adaptable, which means they also benefit the most from cleaner air.

What Schools and Cities Can Do

The researchers highlight that children spend a significant portion of their day on or around school ground.. As a result, schools are key environments for exposure to polluted air.

The study proposes several targeted interventions:

• Installing mobile or centralized air filtration systems in classrooms

• Creating “clean air zones” around schools that restrict high-emission traffic

• Increasing green space in and around school campuses

These actions wouldn’t only improve children’s vision, they could also enhance concentration, reduce allergy risks, and support overall well-being.

Air Quality: A Risk We Can Actually Control

Perhaps the most important takeaway from this study is that air quality is a modifiable risk factor unlike genetics, which we can’t change. This makes it especially powerful from a public health perspective. By improving air quality through policy, technology, and design, we can help protect children’s vision at a time when their eyes are most vulnerable.

Myopia is no longer just an individual condition – it’s becoming a widespread public health issue. This new study from China clearly shows how air pollution is linked to the development of nearsightedness in children. Early investments in cleaner learning environments, especially better air, can have long-term benefits. For children. For families. For society.

Source:

Zhang et al. (2024): “Air pollution and visual acuity in school-aged children: A machine learning approach.”

Available on PMC – National Library of Medicine