Dirty air is linked to glaucoma and cataracts in a review of 41 studies

What happened

People who live in areas with dirtier air appear more likely to develop two of the most common eye conditions, glaucoma and cataract. That is the finding of a large piece of research presented on 15 September 2026 at the 44th Congress of the European Society of Cataract and Refractive Surgeons, one of the biggest eye surgery meetings in the world. The work was presented by Dr Ahmed Alnabihi of the King Khaled Eye Specialist Hospital and Research Center in Riyadh, Saudi Arabia. His team did not run a new experiment. Instead they gathered the results of 41 observational studies, covering millions of people, mainly from East Asia and the United Kingdom, and pooled them together. They looked at several pollutants: fine particles known as PM2.5 and PM10, nitrogen dioxide, sulphur dioxide, ozone and carbon monoxide. The clearest link was with PM2.5. These are tiny particles, small enough to be breathed deep into the lungs, produced by vehicle exhausts, wood burning, industry and smoke. People living in the most polluted areas had up to 70 per cent higher odds of glaucoma than those living in the cleanest areas. Across the studies, each step up in pollution exposure was linked to roughly an 8 per cent rise in the risk of glaucoma and about a 4 per cent rise in the risk of cataract.

Why this matters

Glaucoma and cataract are not rare conditions. In the UK, cataract surgery is the most common operation the NHS performs. Glaucoma affects around 700,000 people in the UK, and it is one of the leading causes of sight loss that cannot be reversed. Glaucoma is particularly worth understanding because of how quietly it starts. It damages the optic nerve, usually because of raised pressure inside the eye. The damage begins at the edges of your vision, where the brain is very good at filling in the gaps. Many people have no idea anything is wrong until a significant amount of sight has already gone, and sight lost to glaucoma does not come back. Cataract is different and much more hopeful. The lens inside the eye clouds over, vision becomes misty or glary, and a routine operation replaces the lens. Most people see well again afterwards. So a study linking both to air pollution touches on something most of us cannot easily change on our own. You can stop smoking. You cannot single-handedly clean up the air on a busy road. That is part of why this kind of evidence tends to be used in arguments about clean air policy rather than personal choices.

What the evidence actually says

The researchers themselves are careful here, and so should we be. Every one of the 41 studies was observational. That means researchers watched what happened to large groups of people. They did not, and could not, randomly assign some people to breathe dirty air. So these studies can show that pollution and eye disease tend to occur together. They cannot prove that one causes the other. That gap matters, because the places with the dirtiest air are often different in other ways too. They tend to be poorer, busier and more built up. People living there may be more likely to smoke, to have diabetes, to work night shifts, or to have less easy access to routine eye checks. Good studies try to adjust for these things. No study adjusts for everything. There is also the question of where the data came from. The studies were mostly from East Asia and the UK. Pollution levels in some East Asian cities are far higher than anything most British residents experience, which makes the 'most polluted' end of the scale hard to translate directly. What gives the finding some weight is that it is biologically plausible. Fine particles are known to cause inflammation and what scientists call oxidative stress throughout the body. The eye is not sealed off from that. There is already good evidence linking air pollution to heart disease, stroke and dementia. Eye disease fitting the same pattern is not a surprise. So the honest summary is: a real and consistent association, across a lot of people, that is plausible but not proven.

Qurexa perspective

There is one genuinely practical thread here, and it is about glaucoma treatment rather than pollution. Glaucoma is usually treated with eye drops, used every single day, often for the rest of someone's life. They do not make you feel better. They do not relieve any symptom. All they do is protect the sight you still have. That combination, daily effort with no immediate reward, makes glaucoma drops one of the treatments people most often fall behind with. Studies have repeatedly found that a large share of patients do not use them as prescribed. This is exactly the kind of gap our prescription delivery and medication adherence support is built for. Getting drops to someone's door before they run out, and a reminder that it is time to reorder, removes two of the commonest reasons people miss doses: the bottle ran out and nobody noticed, and getting to the pharmacy was difficult that week. If you or a relative is on glaucoma drops and keeps running short, that is worth sorting out. It does not have to be with us. But it is worth sorting out with someone, because the sight those drops protect cannot be got back.

Practical advice

You cannot fix air quality by yourself, but there are things within reach. Get your eyes tested regularly. This is the single most useful thing on this list. A routine sight test at an optician checks for glaucoma as well as your glasses prescription, and it can pick up the damage long before you would notice anything. Adults should generally go at least every two years, or more often if your optometrist advises it. In England, NHS sight tests are free if you are over 60, under 16, have diabetes or glaucoma, or are aged 40 or over and have a parent, brother, sister or child with glaucoma. Know your family history. Glaucoma runs in families. If a close relative has it, tell your optician, and get checked from 40 onwards. Reduce the pollution you can control. Indoor air matters too. Do not smoke indoors. Use an extractor fan or open a window when cooking, especially when frying. If you have a wood burner, be aware that it is a significant source of PM2.5 in your own home. On high pollution days, if you have a heart or lung condition, consider quieter routes and less strenuous outdoor exercise. UK air quality forecasts are published by Defra. And if you are already on glaucoma drops, keep taking them, even when nothing feels wrong. That is the point of them.

What to know

Research pooling 41 observational studies, presented at the European Society of Cataract and Refractive Surgeons congress on 15 September 2026, found that people in more polluted areas were more likely to have glaucoma and cataract. The strongest link was with PM2.5, the fine particles from traffic, industry and smoke. People in the most polluted areas had up to 70 per cent higher odds of glaucoma. Because the studies were observational, they cannot prove that pollution causes these conditions, and most of the data came from East Asia and the UK. The most useful action for an individual is unrelated to pollution: have regular sight tests. Glaucoma causes no symptoms until sight has already been lost, and that loss is permanent. Sources: News-Medical, 'Air pollution linked to higher risks of glaucoma and cataract', 15 September 2026, https://www.news-medical.net/news/20260915/Air-pollution-linked-to-higher-risks-of-glaucoma-and-cataract.aspx. Scimex, 'Air pollution linked to glaucoma and cataracts', 15 September 2026, https://www.scimex.org/newsfeed/air-pollution-linked-to-glaucoma-and-cataracts. European Society of Cataract and Refractive Surgeons, 44th Congress, https://www.escrs.org/. This article is for general information and does not replace advice from a doctor, pharmacist, optometrist or other qualified healthcare professional. If you notice any sudden change in your vision, seek urgent medical advice.