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August 2017

LED and its Possible Health Effects – Part 2

Read the first part of this article to understand how the research was conducted and which population groups may be at risk. In this second part of the article, learn more about research results on the effects of LED lamps on general health, the eyes and the circadian system.

The Effect of LED Lamps

They didn’t find evidence of an increased risk of photosensitivity to LED lamps when compared to other lighting technologies. Actually, the absence of ultraviolet radiation from general LED lamps may reduce the risk of photosensitivity for a number of these conditions.

But LEDs do have issues in terms of flicker, dazzle, distraction and glare.

Due to the point-source of some LED lighting, studies have shown that the type of light diffused leads to discomfort and glare.

Some lamps available on the market today incorporate “point” LED sources without diffusers, which can cause a glare when viewed. This was also reported to be a concern with some LED street lights.

Flicker from some LED lamps can result in stroboscopic effects. A small number people claimed adverse health effects such as migraine or headaches. There appear to be no technical reasons why LED lamps need to flicker since many models do not. This is why it is critical to carefully select your LED provider.

Additional Aspects to Consider

The worst-case viewing condition is generally on-axis viewing of a LED source, for example, staring at a screen or an LED lamp. If a source is safe for viewing on axis, it will be safe under all other viewing conditions at the same distance.

Flashing LED sources in the peripheral vision are more likely to cause distraction than those on-axis. LED lamps used for area illumination are usually more energy-efficient than other sources. Take, for example, incandescent lamps. For the same colour temperature, the blue light component of the optical emission is similar to an incandescent lamp. However, infrared (and possible ultraviolet) emissions are greatly reduced, or absent, which might influence the normal human bioprocesses. This aspect is still under investigation.

Circadian System

This topic raises an important question: Does optical radiation from LEDs and artificial light present in indoor lighting and screens have an effect on the circadian system in real life compared to natural light sources? Further research will need to consider emission wavelengths, time of day and duration of exposure, as well as any other confounding factors, such as the activity being carried out, prior light history and the age of subjects.

It is currently not known if the effects on the circadian system remain, are enhanced or reduced after repeated and ultimately, chronic exposure such as currently occurs in real life. Moreover, the potential disturbance caused by LEDs and/or artificial light to the circadian system remains to be investigated. Further investigations will reveal whether these factors are negative health effects, like shift work is to the circadian rhythm.

Effect on the Eyes

There is insufficient knowledge about the actual exposure to optical radiation from LED sources and the total exposure to all optical radiation sources. Information concerning the general healthy population’s exposure is needed to assess potential health effects. It is suggested that exposure assessments should consider different age groups. For example, babies, young children, adolescents, as well as adults into old age.

They recognized that early-to-market LED lamps produced a significant blue emission. Further research is being conducted in order to improve LED lamps to make them similar to traditional types of lighting, such as incandescent lamps. However, it is acknowledged that exposure of the general population to optical radiation from LEDs is likely to be insignificant compared to exposure to natural light outdoors; nevertheless, any additional health burden must be considered.

More Information

Read the first part of this article to understand how research was conducted and which population groups may be at risk.

This article was built on excerpts taken from the article Literature Review Gives LEDs Qualified Pass on Possible Health Effects published by Lighting Design & Specification on August 3rd. Read the full article to learn more about potential health effects of particular LED sources (toys, car lights), the effect on the eyes and the skin and as well as on the circadian system.

Read the entire report on work conducted by the European Commission’s Scientific Committee on Health, Environmental and Emerging Risks:

Read the entire report