Related Experiment Video
Updated: Sep 27, 2026

Determining the Toxicity of UV Radiation and Chemicals on Primary and Immortalized Human Corneal Epithelial Cells
Published on: July 22, 2021
Photokeratitis and other phototoxic effects on the cornea and conjunctiva
1School of Optometry and Department of Biology, University of Waterloo, Waterloo, Ontario, Canada. acullen@uva.uwaterloo.ca
Abstract:
Except when sleeping, the cornea and interpalpebral conjunctiva are exposed to the ambient environment, both natural and man-made. Levels of solar ultraviolet irradiance reaching the eye may exceed the damage threshold under a number of circumstances. The consequences of overexposure may be acute after a latent period, sequelae to an acute exposure, or long-term chronic effects. Previously derived action spectra for photokeratitis and photoconjunctivitis due to incoherent ultraviolet are presented. These reveal interspecies similarities for the levels of radiant energy reaching each tissue. The initial in vivo (clinical) signs of photokeratitis are due to lost or damaged epithelial cells with other signs produced by this primary response. The conjunctival signs include injection and chemosis. Chronic exposure to solar ultraviolet is a factor in climatic droplet keratopathy and pterygium. Phototoxic compounds or their by-products potentially can reach the cornea from the air, via the tears or aqueous humor, or from the limbal capillaries. However, the human cornea appears to be much less susceptible to the influence of phototoxic agents than the skin.
Related Concept Videos
Photoreceptors and Visual Pathways
Microbiome of the Eye
Glaucoma: Overview
Diabetic Retinopathy
Skin Diseases and Disorders
Gram-positive Staphylococcus spp. and Streptococcus spp. are responsible for many of the most common skin infections. However, many...
Ophthalmic Drug Delivery Systems

