Open Letter Regarding Blue Light Research & Blue Light Filtering Lenses
By Essilor Canada
With a mission to improve lives by improving sight, Essilor is committed to vision correction and protection. In recent years, numerous studies from some of the world’s foremost eye health authorities have shown that blue light is one risk factor in the long term health of the eye.
While it is still early on in the exploration of blue light’s health impact, we believe that as a leader in the industry, it is important for us to inform and educate customers (eyecare professionals) and consumers about the potential risks of blue light and to offer technology that can reduce potential negative effects of exposure. This is a serious topic which needs to be addressed with the highest scientific rigor and utmost accuracy in the communications relating to this issue.
Blue Light Research
In addition to the growing body of evidence from the research community, Essilor has conducted with Paris Vision Institute several studies on the impact of blue light on the eye and on the benefits of blue filtering lenses, for which rigorous protocols were scientifically approved by recognized scientists. Our protocols were notably designed to simulate the cumulative effect of blue-violet light on the eye. This led to numerous publications to support our conclusions and claims (see list of publications below, including four independent scientific peer-reviewed papers, among which a recent paper published in Cell Death and Disease where we bring the proof that blue-violet light is a strong inducer of oxidative stress and a strong inhibitor of antioxidant defences).
The largest source of blue-violet light comes from the sun; however, indoor exposure to blue-violet light has been on the rise due to increased use of new artificial light sources as well as screens (cold-white LED’s, LED backlit displays etc.). Research shows that long-term, cumulative exposure to blue-violet light wavelengths (415-455 nm) may be harmful to retinal cells. This type of exposure is one of many risk factors, such as age, genetics, diet, lifestyle and smoking and may contribute to age-related macular degeneration (AMD).
Essilor strives to promote better vision health. We have confidence in the science that our claims are based on. Our wearer tests, which are systematically conducted for each new lens we market, are carried out with the same scientific rigour so as to confirm wearer satisfaction on visual performance and comfort. Our lenses have been developed to filter at least 20% of blue-violet wavelengths, without affecting vision. Additionally, several roundtable discussions involving international boards of experts, including renowned clinicians, researchers and eye care professionals have led to conclude on the precautionary principle and to recommend adequate eye protection.
Research on the harmful effects of blue-violet light is constantly progressing. We remain committed to increasing awareness whilst furthering research efforts to offer our consumers the most advanced vision and protection solutions available.
Blue Light and Visual Fatigue
With regards to visual fatigue and discomfort reduction with blue filtering lenses, we are conscious that scientific evidence with objective measurements still need to be built further, so as to complement subjective questionnaires, and include sufficient mechanism-specific tests to cover most underlying factors, from external to internal symptoms: blinking, ocular surface quality, accommodation and vergence, pupillary light reflex, cognitive and sensory-cortical fatigue. Yet, many wearer real-life studies with subjective assessment report significant alleviation of visual fatigue and discomfort with blue-filtering lenses, all the more when combined to near-vision additional power in a single vision lens. We pursue our research efforts in that field as well.
SCIENTIFIC PUBLICATIONS & COMMUNICATIONS
(1) Sui G.Y. et al. Br. J. Ophthalmol. 2012.
Is Sunlight Exposure a Risk Factor for Age-Related Macular Degeneration? A Systematic Review and Meta-Analysis.
(2)** Nagai H. et al. JCRS 2015.
Prevention of increased abnormal fundus autofluorescence with blue light-filtering intraocular lenses.
Note: fifty-two eyes with a yellow-tinted IOL and 79 eyes with a colourless IOL were included. Two years after cataract surgery, significant differences were seen in the progression of abnormal fundus autofluorescence between the 2 groups. The incidence of AMD was lower in eyes with a yellow-tinted IOL.
(3)** Pipis A. et al. Eur J Ophthalmol 2015
Prevention Effect of blue filter intraocular lens on the progression of geographic atrophy
Note: the clinical data from 66 eyes of 40 patients, 27 with a blue filter and 39 with a non-blue filter IOL strongly support a photoprotective role of blue light-filtering IOLs on the progression of the atrophic form of dry age-related macular degeneration after cataract surgery.
(4) Marquioni-Ramella M.-D. et al. Photochem. Photobiol. Sci. 2015
Photo-damage, Photo-protection and Age-Related-Macular-Degeneration.
(5) Van Norren D. et al. Photochem. Photobiol. 2011.
The action spectrum of photochemical damage to the retina: a review of monochromatic threshold data.
(6) Krigel A., Behar-Cohen F. et al. Neuroscience 2016.
Light-induced retinal damage using different light sources, protocols, and rat strains reveals LED phototoxicity.
(7) Jaadane I., Martinsons C., Behar-Cohen F. et al. Free Radical Biol. and Med. 2015
Retinal damage induced by commercial light emitting diodes (LEDs)
(8) Shang Y.-M., Sliney D. et al. EHP 2014.
White Light-Emitting Diodes (LEDs) at Domestic Lighting Levels and Retinal Injury in a Rat Model.
(9)* Arnault E., Picaud S. et al. PLoS ONE 2013
Phototoxic Action Spectrum on a Retinal Pigment Epithelium Model of Age-Related Macular Degeneration Exposed to Sunlight Normalized Conditions
(9 bis) Marie M. et al. Light action spectrum on oxidative stress and mitochondrial damage in A2E-loaded retinal pigment epithelium cells. Cell Death and Disease (2018) 9:287
(10) Chamorro E., Sanchez-Ramos C. et al. Photochem Phobobiol 2013
Effects of Light-emitting Diode Radiations on Human Retinal Pigment Epithelial Cells In Vitro
(11)** Zhou J., Sparrow JR. Optom Vis Sci 2011
Light filtering in a retinal pigment epithelial cell culture model.
(12)** Park S-I, Jang YP. Ophthalmic Res. 2017
The Protective Effect of Brown-, Gray-, and Blue-Tinted Lenses against Blue LED Light-Induced Cell Death in A2E-Laden Human Retinal Pigment Epithelial Cells
(13)** Sparrow JR, Miller AS, Zhou J. JCRS 2004
Blue light-absorbing intraocular lens and retinal pigment epithelium protection in vitro
(14) ANSEES 2019 (Agence Nationale de Sécurité Sanitaire Alimentation, Environment, Travail)
Environment and Humain Health (Fauna and Flora) Effects from Light Emitting Diode (LED)
ARVO – Poster Communications
(15)* Marie M., Bigot K., Picaud S. et al. ARVO 2015 Poster ref. 4256-C0265
Blue light-induced oxidative stress in an in vitro model of AMD
(16)* Marie M., Picaud S. et al. ARVO 2016 Poster ref. 608-B0081
Blue light decreases oxidative stress defence in an in vitro model of AMD
(17)* Marie M., Barrau C., Picaud S. et al. ARVO 2017 Poster ref. 5859-B0451
Blue light decreases VEGF in an AMD in vitro model of AMD
(17 bis)* Marie M. et al. ARVO 2018 Poster ref. 598-B0270.
In vitro photoprotective effect of optical filters on retinal pigment epithelium cells exposed to moderate daylight-mimicking conditions.
Roundtables on blue light - Publications
(18)* Position Paper from Round Table held in New York City in 2013,
Blue Light Hazard: New Knowledge, New Approaches to Maintaining Ocular Health
(19) Position Paper from Round Table held in London in 2016,
Exploring the latest findings and research in blue light
(20) Position Paper from Round Table held in Paris in 2016,
Ocular light toxicity and the requirement for protection
* Publications and Communications including Essilor researchers
** Publications on blue light filtering lenses and retinal protection