5 ms·

X-rays and Gamma and all the way down to UV are ionizing which is why they are harmful. Radio waves are way below light and infrared as was stated. Forget body

X-rays and Gamma and all the way down to UV are ionizing which is why they are harmful. Radio waves are way below light and infrared as was stated. Forget body heat, why does no one care we are walking around 60w terahertz radiators in our home! Then we go outside and bathe in 1000 watt per meter sunlight which includes ionizing UV. Cell phones put out the equivalent of a low power LED light I am not sure way everyone assumes they cause harm but seem to ignore light bulbs.

phkahler 9y ago
Cell phones emit RF signals that penetrate the body. Lightbulbs for the most part do not. I've always considered the notion of antennas important. Your circulatory system may act as antennas of all different lengths and that would put the received energy right into the blood where it can cause leukemia or other similar cancers. Just speculation of course, but the proposed mechanism applies to RF and not light bulbs.
- ThrowawayR2 9y ago
  > Lightbulbs for the most part do not. 1) Take a flashlight 2) Put a finger over the bulb and turn it on 3) Observe the surprising amount of light that passes through your finger.
  - manmal 9y ago
    Grandparent is right though since most of the blue and green light parts are reflected or absorbed in the top skin layers. Starting with red and infrared, deep tissue penetration is possible. The higher the frequency, the lower its ability to penetrate. That’s why RF can pass through bodies while UV light can’t.
    - SigmundA 9y ago
      Its not as simple as that, X-rays also penetrate but are much higher frequency than UV. The difference as far as health concerns is X-rays cause DNA damage, RF will simply increase temperature. Increase temperature enough and you cause tissue damage of course, but we are talking milliwatts at the transmitter point source that falls off at inverse square, again similar to the amount of heating you would get from a low power LED held near your skin, actually less since as you pointed out RF mainly passes right through us rather than being absorbed. This stuff should continue to be studied, but so should the effects of much higher power light bulbs just in case there is some damaging mechanism yet to be discovered beyond heating your flesh.
- manmal 9y ago
  About the blood-vessels-as-antennas theory, I just want to throw in that blood vessels absorb infrared light well (well duh, blood is quite dark), so at least at that frequency energy is very much absorbed, rather than passed through.
- kobeya 9y ago
  How? “Into the blood” isn’t a mechanism. When was the last time you saw a lump of meat arc and spark? This is fear mongering.
  - userbinator 9y ago
    When was the last time you saw a lump of meat arc and spark? Actually, Google "microwave meat sparking" and you'll find plenty of videos --- but in almost all the cases, the meat is cut in a very specific shape (with sharp edges) that makes it concentrate the RF, and of course being a microwave oven the power density is very high. A human body is, to a rough approximation, a bag of water. It will heat, mostly evenly, when exposed to RF (some parts like the eyes do not have good cooling, hence are more dangerous to irradiate, but this is still a conversation about power levels many orders of magnitude higher than a phone would produce.)
    - kobeya 9y ago
      Microwaves aren’t RF. The frequency has a very specific interaction with water.
      - keenerd 9y ago
        > Microwaves aren’t RF. Yes they are: https://en.wikipedia.org/wiki/Microwave_transmission https://en.wikipedia.org/wiki/Microwave_transmission > The frequency has a very specific interaction with water. No it doesn't: http://wtamu.edu/~cbaird/sq/2014/10/15/why-are-the-microwaves-in-a-microwave-oven-tuned-to-water/ http://wtamu.edu/~cbaird/sq/2014/10/15/why-are-the-microwave...
        kobeya 9y ago
        Your link takes an award for missing the point. There is a resonant frequency of liquid water in the microwave range which is why tabletop microwaves use that range. They don’t emit a single frequency, no, but I don’t know anyone who claims they do...

phkahler 9y ago

Cell phones emit RF signals that penetrate the body. Lightbulbs for the most part do not. I've always considered the notion of antennas important. Your circulatory system may act as antennas of all different lengths and that would put the received energy right into the blood where it can cause leukemia or other similar cancers. Just speculation of course, but the proposed mechanism applies to RF and not light bulbs.

ThrowawayR2 9y ago
> Lightbulbs for the most part do not. 1) Take a flashlight 2) Put a finger over the bulb and turn it on 3) Observe the surprising amount of light that passes through your finger.
- manmal 9y ago
  Grandparent is right though since most of the blue and green light parts are reflected or absorbed in the top skin layers. Starting with red and infrared, deep tissue penetration is possible. The higher the frequency, the lower its ability to penetrate. That’s why RF can pass through bodies while UV light can’t.
  - SigmundA 9y ago
    Its not as simple as that, X-rays also penetrate but are much higher frequency than UV. The difference as far as health concerns is X-rays cause DNA damage, RF will simply increase temperature. Increase temperature enough and you cause tissue damage of course, but we are talking milliwatts at the transmitter point source that falls off at inverse square, again similar to the amount of heating you would get from a low power LED held near your skin, actually less since as you pointed out RF mainly passes right through us rather than being absorbed. This stuff should continue to be studied, but so should the effects of much higher power light bulbs just in case there is some damaging mechanism yet to be discovered beyond heating your flesh.
manmal 9y ago
About the blood-vessels-as-antennas theory, I just want to throw in that blood vessels absorb infrared light well (well duh, blood is quite dark), so at least at that frequency energy is very much absorbed, rather than passed through.
kobeya 9y ago
How? “Into the blood” isn’t a mechanism. When was the last time you saw a lump of meat arc and spark? This is fear mongering.
- userbinator 9y ago
  When was the last time you saw a lump of meat arc and spark? Actually, Google "microwave meat sparking" and you'll find plenty of videos --- but in almost all the cases, the meat is cut in a very specific shape (with sharp edges) that makes it concentrate the RF, and of course being a microwave oven the power density is very high. A human body is, to a rough approximation, a bag of water. It will heat, mostly evenly, when exposed to RF (some parts like the eyes do not have good cooling, hence are more dangerous to irradiate, but this is still a conversation about power levels many orders of magnitude higher than a phone would produce.)
  - kobeya 9y ago
    Microwaves aren’t RF. The frequency has a very specific interaction with water.
    - keenerd 9y ago
      > Microwaves aren’t RF. Yes they are: https://en.wikipedia.org/wiki/Microwave_transmission https://en.wikipedia.org/wiki/Microwave_transmission > The frequency has a very specific interaction with water. No it doesn't: http://wtamu.edu/~cbaird/sq/2014/10/15/why-are-the-microwaves-in-a-microwave-oven-tuned-to-water/ http://wtamu.edu/~cbaird/sq/2014/10/15/why-are-the-microwave...
      - kobeya 9y ago
        Your link takes an award for missing the point. There is a resonant frequency of liquid water in the microwave range which is why tabletop microwaves use that range. They don’t emit a single frequency, no, but I don’t know anyone who claims they do...