Replacing CFL, Halogen and LED light bulbs

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Dangers of CFL Light Bulbs

There are two main health dangers from Compact Fluorescent light bulbs.

1. They give off strong radiation. Some authorities warn about this and provide limits for exclusion zones around such light bulbs.

2. They cause Dirty Electricity on the household wiring circuit. This causes harmful radiation close to wiring near to the light bulb.

Dangers of Fluorescent Tube Lights

There are two main health dangers from Fluorescent Tube lights.

1. They often give off strong magnetic fields from the electronic balance or booster. Some authorities warn about this.
2. They also cause Dirty Electricity on the household wiring circuit. This causes harmful radiation close to wiring near to the light bulb.

Dangers of Halogen bulbs

Halogen bulbs usually put Dirty Electricity frequencies and transients onto house wiring.

Dangers of LED bulbs

1. Dangerous wireless radiation:

​Some LED (Light Emitting Diode) bulbs (GU10) emit VHF radio frequencies, typically in the 30–300 MHz range.

2. Dangerous effects of blue spectrum (a) on the retina and (b) on melatonin, especially at night:

There can also be health damage from these the light spectrum frequencies which produce predominantly UV blue light.

(a) Excess UV blue light can damage the eye. 
Because LED light is so concentrated and has high blue content, it can cause severe glare, resulting in pupillary constriction in the eyes.

Blue light scatters more in the human eye than the longer wavelengths of yellow and red, and sufficient levels can damage the retina.

This can cause problems seeing clearly for safe driving or walking at night.

(b) Used at night in the home or in street lighting this can reduce melatonin in the body and cause circadian disruption. 
Light at night for night workers is rated a 2A probable human cancer agent, partly because of its effect in reducing melatonin.

"Some LED lights are harmful when used as street lighting.
- Discomfort and disability from intense, blue-rich LED lighting can decrease visual acuity and safety,

resulting in concerns and creating a road hazard.
Residents nearby:
- Blue-rich LED streetlights operate at a wavelength that most adversely suppresses melatonin during night.

It is estimated that white LED lamps have 5 times greater impact on circadian sleep rhythms than conventional street lamps.

Recent large surveys found that brighter residential nighttime lighting is associated with reduced sleep times,
dissatisfaction with sleep quality, excessive sleepiness, impaired daytime functioning and obesity.
- Excessive outdoor lighting disrupts many species that need a dark environment. For instance, poorly designed LED lighting
disorients some bird, insect, turtle and fish species, and U.S. national parks have adopted optimal lighting designs
and practices that minimize the effects of light pollution on the environment.
(a) minimize blue-light content:
-The AMA encourages communities to minimize and control blue-rich environmental lighting by using the lowest emission
of blue light possible to reduce glare. The AMA recommends an intensity threshold for optimal LED lighting that minimizes blue-rich light.
(b) shielding and dimming in off-peak periods:
-The AMA also recommends all LED lighting should be properly shielded to minimize glare and detrimental human health
and environmental effects, and consideration should be given to utilize the ability of LED lighting to be dimmed for off-peak time periods."

           American Medical Association: "Community Guidance to Reduce the Harmful Human
and Environmental Effects of High Intensity Street Lighting"

Dangers of Dirty Electricity Transients

Replacement Light Bulbs

You should replace all CFLs and, if possible, LEDs in your house with other light bulbs.

The safest are traditional tungsten filament light bulbs.

These give off almost no radiation and do not cause Dirty Electricity frequencies on household wiring.

They are usually the ideal bulbs but are less energy efficient than some other light bulbs.

Also halogen DC bulbs avoiding dirty electricity are recommended by Dr. Alexander Wunsch: see below.

Health effects of LEDs compared with incandescent lights and practical advice:


Dr J Mercola: "The Dangers of LED Lighting: An Interview With Dr. Alexander Wunsch" (2016):

  • Visible blue light (in visible light, the colour blue has the shortest wavelength and highest frequency) causes physiological effects, such as oxidative stress, disruption of the body’s circadian rhythm and reduction of melatonin, a cancer suppressor.
  • Visible blue light at night, as in shift-work, was classified in 2007 by the World Health Organization’s IARC as a 2A probable human carcinogen.
  • LEDs produce blue light and use a fluorescent sheet to transform some of this blue light into longer wavelengths, such as yellow, but the result is skewed towards blue. Blue causes the greatest oxidative stress but there is insufficient red light and far-infra red radiation, as from incandescent light, at longer wavelengths to help repair tissue damaged by this oxidative stress, especially in the retina, endocrine system, and pineal gland producing melatonin.
  • Sunlight, candles and incandescent lights have a CRI (Colour Rendering Index) of 100 and this should be the health standard for LEDs too.
  • True colour temperature is 5,500 Kelvin for the sun and up to 3,000 Kelvin for incandescent lights.
  • Correlated colour temperature is based on a variety of calculations and assumptions about what may reach the eye and is unreliable for measuring cellular biological harm. If the LED has 3 white LED filaments and one red LED filament, the cellular biological effects of the 3 white LEDs is not compensated for by the red LED, even though the resulting light may appear less blue.
  • The healthiest and most energy efficient light source for 400-1,400 nanometers is a halogen incandescent bulb running on 6 or 12 volts DC. This is much more energy efficient than LEDs. Direct current also eliminates the dangerous dirty electricity and flicker from LEDs. Halogen is up to 100% more energy efficient compared with some other incandescent lamps and for light hygiene produces the infra-red vital for the retina.

Research into Photobiology

Light at Night, Cancer, Melatonin, Cryptochrome, Magnetoreception

Shiftwork with light at night is classified as a human carcinogen.
Blue light, common in LEDs, smart phones and computers, reduces melatonin. 
Melatonin both helps defend against cancer and helps control circadian rhythms and the body clock. 
Blue light has an effect on cryptochromes by the radical pair mechanism.
Cryptochromes are found in both animals and humans, 
Cryptochromes are part of the magnetoreception system in animals.

Some health effects of different light levels:

Amount of light
(Lux = 1 lumen per square meter)
 Source of light, 
​or location 
 Health effects  
Moonlit night

3Street lamp through bedroom curtains

Light at night: increased depression in elderly.*
Light at night: increased subclinical carotid atherosclerosis in elderly.**
Artificially lit room


Light in evening: suppresses melatonin.***
Typical office lighting
Shiftwork involving circadian disruption: 2A (probable) carcinogen: WHO/IARC.****
Daylight, winter, cloudy

30 000-100 000 
 Daylight, summer, clear sky

Obayashi K et al, 2018
** Obayashi K et al, 2015
*** Gooley JJ et al, 2011
****WHO/IARC, 2007

The Microworld/Infrared, Visible Light, the Nanoworld/Ultraviolet, X-rays

  • The Microworld (Infrared Spectrum):
    Wavelength:   0.1 mm = 100 micrometers  to  1 micrometer = 1,000 nanometers
    Frequency:     0.3 - 700 THz
    ​Size:                Human Hair width:  60-120 micrometers
                            Red Blood Cells:       7-8 micrometers

  • Visible Light (Visible Spectrum):
    Wavelength:   790 (red) - 390 (violet) nanometers.
    Frequency:     430 – 770 THz

  • The Nanoworld (Ultraviolet Spectrum):
    ​Wavelength:   0.1 micrometer = 100 nanometers  to   1 nanometer
    ​Frequency:     750 - 30,000 THz
    Size:                 ATP synthase and proteins:  10 nanometer
                             DNA:                                          0.5-2 nanometer
  • X-ray Spectrum:
    Wavelength:   0.01 to 10 nanometers,
    Frequencies:  30 petahertz to 30 exahertz (3×10-16 Hz to 3×10-19 Hz)