Replacing CFL, Halogen and LED light bulbs

            back to: Practical advice

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.

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

H. Peter Aleff: "Baby-blinding retinopathy of prematurity and intensive care nursery lighting" (Latrogenics, 1991)

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" (2016)

  • 3. Interference:

LEDs can also over-ride DAB (Digital Audio Broadcasting) radio signals and cause other interference.

Dangers of Dirty Electricity transients

Replacement light bulbs

You should replace all CFLs 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.

Research into Photobiology

Light at night, cancer, melatonin, cryptochrome, magnetocereception

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
0.3Moonlit night
3Street lamp through bedroom curtains

Light at night: increased depression in elderly.*

Light at night: increased subclinical carotid atherosclerosis in elderly.**

100-300Artificially lit room
Light in evening: suppresses melatonin.***
300-500Typical office lightingShiftwork involving circadian disruption: 2A (probable) carcinogen: WHO/IARC.****
1000-2000Daylight, winter, cloudy
30 000-100 000Daylight, summer, clear sky

* Obayashi K et al, 2018

** Obayashi K et al, 2015

*** Gooley JJ et al, 2011

****WHO/IARC, 2007