A new study says people living in heavily polluted areas face a higher risk of severe medical conditions, including permanent blindness in children.
Researchers in China assessed 30,000 schoolchildren for myopia, or nearsightedness, a condition that affects nearly half of Americans. While they found that severe cases were most strongly linked to genetic factors and younger age, milder cases were found to be tied to modifiable risk factors, like environmental contaminants emitted by cars.
It is believed that air pollution can inflame the eye and disrupt the tear film, a protective barrier that surrounds the eye. Pollutants may also be responsible for damaging the cornea and driving scarring.
Notably, the researchers found that reducing chemical contaminants by approximately 20% resulted in improved vision scores among children with mild myopia. They theorize that reducing pollution levels while children’s eyes are developing could help improve vision before more severe, lasting effects take hold.
“While genetics and screen time are long recognized as contributors to childhood myopia, this study is among the first to isolate air pollution as a meaningful and modifiable risk factor,” said Professor Zongbo Shi, co-supervisor of the study and professor of atmospheric biogeochemistry at the University of Birmingham in the UK, per the Daily Mail.
“Clean air isn’t just about respiratory health – it’s about visual health too. Our results show that improving air quality could be a valuable strategic intervention to protect children’s eyesight, especially during their most vulnerable developmental years.”
Roughly 81% of severe myopia cases were found to be directly tied to non-modifiable risk factors, like genetics, but just 4.3% were tied to environmental factors. With milder myopia, however, environmental factors explained 12% of cases. Moreover, behavioral factors, such as sleep and the amount of time spent in green spaces, accounted for almost 14% of cases.
“This pattern indicates that in children with school myopia, differences in pollution exposure have a stronger impact on vision, whereas in severe myopia cases, vision impairment is mainly driven by demographic factors, leaving environmental influences less influential,” the researchers concluded.