Which environmental exposure is a risk factor for pterygium?

Which environmental exposure is a risk factor for pterygium?

• A. Excessive UV exposure
• B. Smoking
• C. Low humidity environment
• D. Bacterial infection

Answer: (A)

Excessive ultraviolet exposure is the main environmental trigger for pterygium. UV light, especially UV-B, damages the conjunctival and limbal tissues, promoting fibrovascular growth that can extend onto the cornea. This is why pterygium is common in people who spend a lot of time outdoors in sunny, dusty, or windy environments, and why protective measures like UV-blocking sunglasses reduce risk. Smoking, low humidity, and bacterial infection are not established causes of pterygium. Smoking is linked to other eye problems, not this fibrovascular growth; low humidity may irritate the eye but doesn’t drive pterygium formation; bacterial infections can cause conjunctivitis but not the degenerative-libial process that leads to pterygium.

Excessive ultraviolet exposure is the main environmental trigger for pterygium. UV light, especially UV-B, damages the conjunctival and limbal tissues, promoting fibrovascular growth that can extend onto the cornea. This is why pterygium is common in people who spend a lot of time outdoors in sunny, dusty, or windy environments, and why protective measures like UV-blocking sunglasses reduce risk.

Smoking, low humidity, and bacterial infection are not established causes of pterygium. Smoking is linked to other eye problems, not this fibrovascular growth; low humidity may irritate the eye but doesn’t drive pterygium formation; bacterial infections can cause conjunctivitis but not the degenerative-libial process that leads to pterygium.