Summary
Light is electromagnetic radiation. Generally, electromagnetic radiation is hazardous. Sunlight can cause sunburn and damage our eyes. Light at night can interfere with our hormonal processes, leading to disease. Light impacts our mood. Blue light is especially hazardous, but is also critical for controlling our circadian rhythms. Therefore, if we use artificial light sources, we must take great care.
LEDs emit electromagnetic radiation in the Visible Light portion of the spectrum. However, the only similarity between LED light and traditional light sources such as the sun, a candle, and even an incandescent light bulb is that we can detect the LED light with our eyes, skin, and nerves. Other than that, there are essentially no similarities between LED Visible Light radiation and sunlight or candlelight, or incandescent light. LED light should have remained confined to the laboratory rather than having been released into our environment.
Spatially, LEDs emit light from a flat surface, which creates a directed energy beam of non-uniform energy (a Lambertian mathematical shape), whereas a traditional light source such as the sun emits spatially uniform energy. Spectrally, LEDs often emit extreme levels of blue wavelength light, with no counterbalancing red light, whereas sunlight at noon emits nearly the same level of each visible wavelength. Temporally, LEDs exhibit square wave flicker, especially with low quality electronics or with the use of Pulse Width Modulation, whereas incandescent light bulbs emit sine wave flicker.
The categories of harm from LED light include photobiological harm, neurological harm, psychological harm, and hormonal harm. The intensity of the light from a flat surface LED chip is called luminance. The luminance from today’s LEDs can be millions of times more than the intensity of light reflected from a tree or a street. The hazards of high luminance LED light is amplified by the spectral properties of LED light, and further amplified by the digital pulsing of LED light. There are no government regulations to protect the public from this hazardous Visible Light electromagnetic radiation.
Photobiological (Eye) Damage
LED radiation is dense in the center and will cause eye damage. Gearlight, a maker of LED flashlights, warns users to not look directly at the light or shine it into anyone’s eyes.
Toolmaker Ryobi also warns users that LED light beams remain dense and dangerous even at long distances.
The rest of the industry, however, is not warning the public of the dangers of LED radiation. There is no warning on an LED streetlight that tells the public not to look directly at the light. Car headlights are aimed directly at oncoming drivers, but there is no warning about how much damage is being done to the eyes. These warnings were not necessary for traditional light sources such as High Pressure Sodium or tungsten filament because the light intensity is low and contains little blue.
Risk Groups
Neurological (nervous system) Interference
LED radiation causes epileptic seizures, migraines, psychological trauma, and thoughts of suicide.
Epilepsy – Details on how LEDs affect people with epilepsy.
April, 2021 – What is Photobiological Safety Standard? –
May, 2020 – Light Emitting Diodes: Implications for Safety – Quote: “Currently, as noted below in the section on LED specifications, the state-of-the-art SLEDs can emit as much as 50 W cm−2 sr−1 (500 kW m−2 sr−1).” = 341,500,000 nits of luminance at 555nm.
July, 2019 – High-radiance light sources with LED-pumped luminescent concentrators applied to pump. – Quote: “By power scaling of LEDs pump concentrators we demonstrated a visible light source (centered at 550 nm) producing 294 W with a radiance of 668 W/cm2 /sr in the air.”
June, 1976 – Very High radiance edge-emitting LED – Quote: “In this paper we describe a new light-emitting diode (LED) whose radiance is 1000 W/cm 2 sr, an order of magnitude higher than any previous LED.”
IEC-EN-62471 – Requirements for Risk Group Classifications – Exposure Times – Any lamp that causes poses a hazard even for momentary or brief exposure is classified as Risk Group 3. If a lamp poses a retinal thermal hazard or blue-light hazard in less than 1/4 of a second, then that lamp is classified as Risk Group 3. A lamp that poses a retinal thermal hazard after at least 1/4 of a second, but less than 10 seconds, is Risk Group 2.
Conversion of luminance to radiance at 555nm.
1 nt = 1.4641288433382E-7 watt/sq. cm/steradian (at 555 nm)
1 watt/sq. cm/steradian (at 555 nm) = 6830000 nt [f]
Conversion formulas: http://www.dfisica.ubi.pt/~hgil/Fotometria/HandBook/ch07.html
Light Measurement Handbook: http://www.noveldevicelab.com/files/2018-11/Light%20MeasurmentHandbook.pdf
Read these personal stories to get a feel for how harmful LED radiation devices are.
Quotes from Individuals Harmed by LED Exposure – This paper contains quotes from real people who have been injured by LED light beams.
The Negative Effects of Artificial Light – This document by the Soft Lights Foundation lists numerous studies that confirm that artificial light at night is a toxin. This document also contains the studies that show that artificial light at night does not increase safety or reducing property crime. Light trespass is a nuisance. The document is double-spaced so that it can be submitted to the Courts.
One-third of us At Risk – The Medical Science of LEDs – This paper summarize the history of the LED fraud and how the impacts of LED light beams are ignored for large parts of the population, including babies, teenagers, the elderly, and those with autism and epilepsy. The paper contains a lengthy list of links to original research.
Psychological Disturbance
Panic attacks, anxiety.
Hormonal Interference
Artificial light at night, especially blue wavelength light, greatly increases the risk of thyroid cancer, prostate cancer, breast cancer, diabetes, heart disease, mood disorders, premature birth, and early mortality.
April, 2019 – ANSES – On the “effects on human health and the environment (fauna and flora) of systems using
light-emitting diodes (LEDs)”
June, 2018 -European Commission Scientific Committee on Health, Environmental, and Emerging Risks – Opinion on Potential Risks to Human Health of Light Emitting Diodes –
September 2015 – Blue Light Hazard and Risk Group Classification of 8 W LED Tubes –
LED Incident Reports
The Soft Lights Foundation collects reports of harm from exposure to LED Visible Light radiation which are reported here.