ErgoPractice News – October 2015
Exposure to Extreme Blue LED Headlights Negatively Affects Ocular Health
The same type of blue light in a curing light is in other light sources, such as the sun. Then why is indirect sunlight not dangerous to our eyes? Because the dangerous blue light is mixed with other color lights and our eyes can react accordingly. Our eyes detect the bright light and our iris’ close down, to prevent overexposure. However, strong blue light sources are not natural, our iris’ don’t react as they should and lets in all the dangerous blue light.1
Many LED Headlights have a blue tint to their beam color because they have a strong peak near the 445nm wavelength.2 This is why such lights give our eyes the ‘bright sensation.’ Our eyes are trying to tell us our iris’ cannot adjust and we should look away. Research indicates possible effects from long-term exposure to ‘extreme-blue’ LEDs may include early-onset macular degeneration, photokeratitis (cornea burns) and retinal cell damage.3
I had read about these issues in various journals many years ago. At that time I decided SurgiTel had to develop a technology to ensure the safety of our customers, in the same way our ergonomics loupes support long term clinician health. This is why we developed the patented, multi-lens, achromatic beam optics which help create a ‘natural,’ safe color balance in our Micro & Mini LED Headlights. (See Color Balance Examples)
And yet, even today, extreme cool LED Headlights with non-achromatic (color-dispersed) beams are being sold as safe equipment. One reason is many mistakenly believe greater brightness equals greater image quality. Thus, clinicians are led to blue LEDs giving the ‘brightness’ sensation. Another is there are no OSHA or other guidelines limiting blue light emissions of LEDs.
Catherine Stamatacos D.D.S. and Janet L. Harrison D.D.S. utilized their research into the blue light hazard to create a continuing education course titled “The Possible Ocular Hazards of LED Dental Illumination Applications”
This piece discusses the technology behind LED lights and what role blue light plays in the spectral emissions. They reveal the difference between the 555 nm peak, the 445 nm peak, and what a balance of these mean. And, following, they explore the possible health implications of these factors.
- Clinicians Report, Is your LED headlamp damaging your eyes?, A Publication of CR Foundation, March 2013, www.CliniciansReport.org
- Stamatacos, Catherine, DDS, and Janet L. Harrison, DDS. “The Possible Ocular Hazards of LED Dental Illumination Applications.” TDA Journal – Continuing Education 93-2 #51 (2013): 25-31. Web. 22 Oct. 2015.
- Price Curing Lab. “The Blue Light Hazard in Medicine and Dentistry.” YouTube. Price Curing Lab, 22 July 2012. Web. 24 Apr. 2015. <https://youtu.be/VfCmL4Kz2iw>.