It is known that air pollution has direct repercussions on our respiratory and cardiovascular health. But did you know that it also poses a silent threat to our eye health? Recent scientific research highlights a concerning link between chronic exposure to fine particles and the increased risk of glaucoma, particularly in predisposed individuals.
As opticians and visual health professionals, at Michils Opticians, we believe that informing our patients is the first step in prevention. Let's take stock of what science says.
What do scientific studies say?
Several large epidemiological studies have examined the impact of air quality on vision. One of the most notable, conducted by British researchers and published in the prestigious British Journal of Ophthalmology, analysed data from over 110,000 people over several years.
The conclusions are unequivocal: individuals living in areas where concentrations of fine particles (PM2.5 and PM10) exceed recommended thresholds have a significantly higher risk of developing glaucoma and experiencing degradation of their optic nerve.
How do fine particles impact our eyes?
Glaucoma is an optic neuropathy that progressively destroys the fibres of the optic nerve, often linked to elevated intraocular pressure (IOP). Air pollution contributes to this process through several biological mechanisms:
Oxidative stress and inflammation: PM2.5 particles are so tiny that they pass through the pulmonary alveoli to enter the bloodstream. They induce widespread oxidative stress and inflammatory reactions that weaken nerve cells, including at the level of the eye.
Alteration of blood circulation: Pollution causes endothelial dysfunction (alteration of the blood vessel wall), which can reduce the micro-perfusion of blood supplying the optic nerve. A less well-perfused optic nerve is more vulnerable.
The direct impact on eye pressure: Although research is ongoing, local chronic inflammation could disrupt the drainage of fluid inside the eye, leading to an increase in intraocular pressure.
Who is most affected?
Glaucoma is a multifactorial condition. While everyone is exposed to urban pollution, the risk is particularly heightened for the predisposed individuals, that is to say:
Those with a family history of glaucoma.
Individuals with detected ocular hypertension.Subjects over 45 years old.
City dwellers exposed daily to heavy road traffic (high concentrations of diesel particles and brake dust).
How to protect yourself?
How to protect yourself?
It is difficult to completely escape urban pollution, especially in a large city like Brussels. However, a few habits can help limit the risks:
Monitor air quality: In case of a spike in fine particle pollution, avoid intense physical exertion outdoors (which increases respiratory rate and pollutant absorption).
Protect your eyes from wind and dust: Wearing prescription or sunglasses outdoors already acts as a first physical barrier against direct projections and polluted air flows.
Do not neglect your regular check-ups: Glaucoma is a sneaky disease as it is completely painless and does not lead to an immediate decrease in vision (peripheral vision deteriorates last). An annual check-up with your ophthalmologist, combined with monitoring your visual health with your optometrist, remains your best ally for early detection.
Reference sources :
British Journal of Ophthalmology - Studies on the association between air pollution (PM2.5, PM10) and the prevalence of glaucoma.
Recommendations from the World Health Organization (WHO) on air quality thresholds and health impact.