The researchers identified a band of blue-violet light that is particularly phototoxic to RPE cells.
Blue-violet light has been shown to cause significant morphological changes in RPE cells, such as rounding of the cells and a decrease in cell density, which are symptoms of cell death, or apoptosis. The greatest damage was observed in cells exposed to wavelengths between 415 nm and 455 nm, confirming the high phototoxicity of this specific band.
The eye’s natural protective mechanisms against harmful blue light are not sufficient in the excessive light exposure of modern societies. Experts agree on the need for additional measures
Macular pigment, which consists of carotenoids such as lutein and zeaxanthin, effectively filters short-wavelength radiation before it reaches the photoreceptors and RPE, providing natural protection against blue light damage. However, as we age its levels drop and the lens of the eye begins to yellow, reducing the eye’s ability to filter out harmful blue light. This leads to greater exposure and cumulative retinal damage and can accelerate age-related macular degeneration (AMD).
Given these findings, experts recommend additional protective measures that selectively filter out harmful wavelengths of blue light without affecting beneficial wavelengths that regulate circadian function. Research has identified a specific narrow band of blue-violet light (435 nm ± 20 nm) that is particularly harmful to retinal pigment epithelial cells, and lenses have been developed to block this specific wavelength. Such protective mechanisms could also be an essential element of preventive eye care in the future.
