In the current climate crisis we face today, we inevitably come into contact with air pollution mixed in the air. Air pollution contains key compounds such as Carbon monoxide, Nitrogen dioxide, Ozone, Sulphur dioxide, as well as PM10 and PM2.5 dust particles, which may contain toxic substances hidden within these fine particles, including mercury, cadmium, or lead.
When we have to live with air filled with these polluted dust particles, it is not only harmful to the body, including the respiratory and cardiovascular systems, but it also significantly affects our eyes, both in the short and long term. Especially the conjunctiva and cornea, which are directly exposed to dust particles. Normally, the surface of our eyes is protected only by a thin layer of tears. If exposed to polluted and dense dust conditions, especially fine PM2.5 dust, abnormal symptoms will occur immediately, such as irritation, discomfort, conjunctivitis, red eyes, increased dry eye condition, blocked or infected eyelid glands, and abnormalities in the retinal blood vessels.
How does air pollution affect eye diseases?
- The conjunctiva is the area directly exposed to external factors. When abnormal, symptoms include itchy eyes, tearing, light sensitivity, and conjunctivitis. Prolonged exposure to pollution causes cellular changes, abnormal shapes, stimulates secretion of inflammatory substances, leads to allergic eye conditions, chronic dry eye, and increases susceptibility to secondary infections.
- Dry eye disease: Levels of dust pollution and humidity in the air are related to dry eye symptoms, causing the tear film to evaporate faster than normal. Contact lens wearers or those with pre-existing dry eye conditions are more sensitive to dust effects.
- Meibomian gland dysfunction, a cause of dry eye, has been found in research to worsen with poor air quality, increasing inflammation and blockage of the eyelid glands.
- Blepharitis caused by fine dust and smoke leads to irritation combined with bacterial infection, resulting in styes.
- Effects on the cornea: PM2.5 dust causes changes and reduced function in the outer corneal cells, affecting vision levels.
- Retina: Research shows that exposure to fine dust such as PM2.5, PM10, and carbon dust, even for a short period, causes narrowing of retinal blood vessels, leading to abnormal blood circulation and retinal hypoxia, which can result in abnormal vision.
Additionally, air pollution may be associated with the development of cataracts and glaucoma.
Regarding the continuously increasing PM2.5 dust situation, when living with poor air quality, it is important to be aware of its relationship with eye diseases.
Recommendations for protecting and caring for the eyes
- Avoid staying outdoors for long periods.
- Wear glasses to protect against wind and dust when going outside.
- Regularly use artificial tears to lubricate the eye surface and dilute irritants from air pollution.
- Do not rub your eyes when irritated, as this may cause secondary infections.
- If experiencing itchy or swollen eyes, cold compresses can help relieve symptoms initially.
- Clean the face and around the eyes with clean water; eyelashes can be washed with warm water or mild baby shampoo.
- Contact lens wearers or those with pre-existing eye conditions such as dry eye, allergic conjunctivitis, pterygium, or pinguecula may be more sensitive to dust and at higher risk of complications. If other abnormal symptoms occur, consult a specialist for a thorough eye examination.
Dr. Kittikamon Wongpaisansin
Ophthalmologist specializing in cornea and vision correction
Eye Clinic, Phyathai 3 Hospital
