Beyond skin, eyes also require protection from sun exposure. Excessive exposure to ultraviolet (uv) radiation can cause temporary damage to this organ.

Cornea can be damaged

When eyes are overexposed to ultraviolet (uv) radiation, the outermost layer of corneal cells can be damaged and peel off, exposing sensitive nerve endings underneath. This condition is known as uv keratitis (photokeratitis), often likened to a "sunburn of the eye".

The cornea is the transparent, dome-shaped layer at the front of the eye, focusing light for clear vision. The conjunctiva, a thin membrane covering the white of the eye and the inside of the eyelids, can also be affected.

Ultraviolet (uv) radiation from sunlight can temporarily damage the cornea. *AI-generated image*

Eyes may sting and feel gritty

Uv keratitis typically affects both eyes due to simultaneous exposure to the uv source. Symptoms include a gritty sensation in the eyes, pain or burning, redness, swelling, tearing, light sensitivity, and headaches. In rare cases, temporary vision changes or loss of sight may occur.

Symptoms may not appear immediately after uv exposure. They typically begin 6-12 hours post-exposure, meaning an individual might feel normal outdoors but start experiencing pain, grittiness, or light sensitivity that evening or the next morning. Longer and more intense exposure can lead to earlier and more severe symptoms.

Direct sunlight is not the only source of eye damage. Uv rays can reflect off water, sand, concrete, and snow, entering the eyes from various angles. The risk also increases at high altitudes due to stronger uv radiation.

Symptoms tend to resolve on their own within 24-48 hours as the corneal surface cells regenerate. During this period, affected individuals should avoid rubbing their eyes, remove contact lenses, rest, and limit exposure to bright light.

Closing eyes, applying a cool compress, and using preservative-free artificial tears can alleviate discomfort. Over-the-counter pain relievers may be used if suitable for one's health.

The best way to reduce the risk of uv eye damage is to wear sunglasses that block 100% of uva and uvb rays. Glasses should fit relatively close to the eyes and can be paired with a wide-brimmed hat when outdoors.

Polarized lenses reduce glare but do not guarantee full uv protection. Therefore, when selecting eyewear, it is still essential to check for uva and uvb protection information. Specialized protective eyewear or equipment is necessary when working outdoors in intense sunlight or performing welding tasks.

Bao Bao (compiled)