Cell/Mobile Phone & Wi-Fi Signals Dangerous?

[ChrisTheFeral]

I was wondering if there was any real science behind the claims that radiation from routers and phone towers are dangerous. It would seem that the radio waves that many devices work on are lower energy than that of light. My thought is that turning a light on would be more dangerous than turning on a Wi-Fi router simply based on the energy of the radiation.

Edited May 21, 2011 by ChrisTheFeral

[Klaynos]

None that I've ever seen, some has suggested that very close continuous use of mobile antenna can lead to warming of the brain. But others have found differently.

 

There's two things which could feasibly lead to it being dangerous imo... microwave radiation has a longer wavelength than optical, so it will be more penetrating (there are other factors as well, but it will penetrate further into the skin/body), water (and other chemical present in humans) have high absorption peaks at microwave frequencies, which can lead to excessive heating (microwave ovens as an example). But that is more likely to happen on the edges of the skin, as that is where the highest fields are, with reduced penetration from the wavelengths that are at the high absorption locations, because well they're getting absorbed quicker...

 

I think I should point out I'm not a biologist, but a physicist, I do work with microwave emitters and detectors very regularly though...

[ChrisTheFeral]

None that I've ever seen, some has suggested that very close continuous use of mobile antenna can lead to warming of the brain. But others have found differently.

 

There's two things which could feasibly lead to it being dangerous imo... microwave radiation has a longer wavelength than optical, so it will be more penetrating (there are other factors as well, but it will penetrate further into the skin/body), water (and other chemical present in humans) have high absorption peaks at microwave frequencies, which can lead to excessive heating (microwave ovens as an example). But that is more likely to happen on the edges of the skin, as that is where the highest fields are, with reduced penetration from the wavelengths that are at the high absorption locations, because well they're getting absorbed quicker...

 

I think I should point out I'm not a biologist, but a physicist, I do work with microwave emitters and detectors very regularly though...

 

Ah k, that's interesting. That's actually something else I've been wondering about, I thought that higher frequency waves were more penetrating because of the amount of energy they had - I've been wondering how microwaves work exactly to heat food. So, basically what you're saying is that the radiation reacts differently depending on the material?

 

Thanks for the response

[Klaynos]

Yes, the electric field interaction is controlled by the permittivity of a material and the magnetic field by the permeability. For most of what I work with the relative permeability is taken to be 1, so is the same as free space. These are wavelength dependent, hence rainbows through prisms.

 

For penetration depth, if we consider the skin depth (which isn't really fair as we are not good conductors) I'm failing to find a good reference at the moment, but it scales with wavelength. So the longer the wavelength the deeper the penetration, this is true for most EM phenomena, radiation of any given wavelength will do the most interesting things when interacting with stuff of the same order of magnitude in size...

[ChrisTheFeral]

Yes, the electric field interaction is controlled by the permittivity of a material and the magnetic field by the permeability. For most of what I work with the relative permeability is taken to be 1, so is the same as free space. These are wavelength dependent, hence rainbows through prisms.

 

For penetration depth, if we consider the skin depth (which isn't really fair as we are not good conductors) I'm failing to find a good reference at the moment, but it scales with wavelength. So the longer the wavelength the deeper the penetration, this is true for most EM phenomena, radiation of any given wavelength will do the most interesting things when interacting with stuff of the same order of magnitude in size...

 

That makes so much sense now, thanks for explaining!