Blue Light Exposure: Ocular Hazards and Prevention—A Narrative Review

Abstract

Introduction Exposure to blue light has seriously increased in our environment since the arrival of light emitting diodes (LEDs) and, in recent years, the proliferation of digital devices rich in blue light. This raises some questions about its potential deleterious effects on eye health. The aim of this narrative review is to provide an update on the ocular effects of blue light and to discuss the efficiency of methods of protection and prevention against potential blue light-induced ocular injury. Methods The search of relevant English articles was conducted in PubMed, Medline, and Google Scholar databases until December 2022. Results Blue light exposure provokes photochemical reactions in most eye tissues, in particular the cornea, the lens, and the retina. In vitro and in vivo studies have shown that certain exposures to blue light (depending on the wavelength or intensity) can cause temporary or permanent damage to some structures of the eye, especially the retina. However, currently, there is no evidence that screen use and LEDs in normal use are deleterious to the human retina. Regarding protection, there is currently no evidence of a beneficial effect of blue blocking lenses for the prevention of eye diseases, in particular age-related macular degeneration (AMD). In humans, macular pigments (composed of lutein and zeaxanthin) represent a natural protection by filtering blue light, and can be increased through increased intake from foods or food supplements. These nutrients are associated with lower risk for AMD and cataract. Antioxidants such as vitamins C, E, or zinc might also contribute to the prevention of photochemical ocular damage by preventing oxidative stress. Conclusion Currently, there is no evidence that LEDs in normal use at domestic intensity levels or in screen devices are retinotoxic to the human eye. However, the potential toxicity of long-term cumulative exposure and the dose-response effect are currently unknown.

Polydopamine Nanoparticles as Mimicking RPE Melanin for the Protection of Retinal Cells Against Blue Light-Induced Phototoxicity

“…Ocular phototoxicity involves damage caused by exposure to light, particularly short-wavelength blue light, leading to harmful reactions in ocular tissues. Although ordinary ambient sunlight exposure does not cause phototoxicity, the concern is that prolonged or intense blue light exposure could contribute to ocular phototoxicity [32,35] . Short-wavelength blue light easily penetrates through the lens to reach the RPE cells, and then interacts with accumulated lipofuscin, as well as photosensitizers such as flavin and porphyrins within abundant mitochondria in retina cells [5,12] .…”

“…Blue light and its potential connection to ocular phototoxicity have been subjects of scientific investigation [4,[32][33][34] . Ocular phototoxicity involves damage caused by exposure to light, particularly short-wavelength blue light, leading to harmful reactions in ocular tissues.…”

The potential retinal blue hazard from dental examination lamps at different ages

“…Even though dentists and attending staff are unaffected by indirect viewing of light, eye protection is important. Concerns are developing that the population is exposed to increased blue light from multiple sources [25]. The widespread usage of blue light-emitting sources concerns all ages [25].…”

Shifting landscapes: The environmental impact of urbanisation on childhood myopia, obesity and diabetes

“…20 Young children are especially susceptible to their visual environment 21 and more sensitive to the blue light spectrum than adults due to their clear crystalline lens. 22 Exposure to blue-rich white light from screens and digital devices in the evening and at night disrupts sleep and natural ocular diurnal cycles, potentially impacting choroidal thickness and axial growth. For instance, Burfield et al 23 identified diurnal variations in ocular parameters such as choroidal thickness, axial length, intraocular pressure and ocular perfusion pressure.…”

“…Rapid urbanisation and related lifestyle changes have long been linked to a significant increase in myopia globally 20 . Young children are especially susceptible to their visual environment 21 and more sensitive to the blue light spectrum than adults due to their clear crystalline lens 22 . Exposure to blue‐rich white light from screens and digital devices in the evening and at night disrupts sleep and natural ocular diurnal cycles, potentially impacting choroidal thickness and axial growth.…”