# Do mobile phones produce radiation harmful to humans? [closed]

What are the health effects of mobile phone radiation (if any)? Does using a mobile phone without an SIM card change the answer?

## closed as off-topic by David Hammen, ACuriousMind♦, Kyle Kanos, Ben Crowell, Brandon EnrightNov 14 '14 at 2:58

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• This question appears to be off-topic because it is (probably) about health effects of technology. – ACuriousMind Nov 14 '14 at 0:07
• The question presupposes facts not in evidence. – dmckee Nov 14 '14 at 2:27
• Health effects are still a physiological response to certain stimuli; this is still outside the realm of physics. – Kyle Kanos Nov 14 '14 at 19:46
• @KyleKanos should physics.stackexchange.com/questions/10789/… and physics.stackexchange.com/questions/18471/… also be off-topic? Does the question "How does light of a certain frequency interact with the human body" not fall in the realm of the biophysics tag? I'm new, sorry, just trying to understand what's acceptable & what's not. – pentane Nov 14 '14 at 20:45
• @pentane: Note that both questions are old and that policies change over time (hence the need for the meta site). I would say that any question asking about the interaction of the human body and any stimuli is not biophysics (or any other subset of physics). – Kyle Kanos Nov 14 '14 at 21:01

Mobile phones output UHF and long microwave frequency radiation; roughly 1GHz. These are not ionising radiations, which begin at ultraviolet light frequencies and above (several eV photon energies and above). 1eV is about 250THz, or five orders of magnitude greater than GHz photons in energy per photon. GHz photons thus have negligible effect on atoms and molecules, so there is therefore negligible risk of the mutagenic effects that go with e.g. radiation from nuclear processes.

On the other hand, microwaves induce local heating effects in living tissue. This is simply dissipative losses as ions are vibrated by the electromagnetic radiation (the $\vec{J}=\sigma\,\vec{E}$ term in a linear material). One therefore cannot altogether rule out the risk of some permanent tissue damage from mobile phone use in some case. Reasons for further believing the risk is low are:

1. The brain is the most heavily envasculated organ so that its temperature can be kept rock solid stable by the blood that carries heat off elsewhere: even a $41{\rm C}$ fever doesn't often lead to brain damage, even thought the brain dies at this temperature. The brain is kept at a much lower temperature than the main body in a fever. So there should be a resilience to local heating.

2. We now have fairly good epidemiological data for the effects of their use, given that almost all of first world citizens have had them glued to their ears for at least 10 years.

Lack of a SIM card makes no difference: the phone is still trying to talk to the network and is therefore outputting EM radiation. However, you're not likely to use a mobile for very long if it lacks one!

1) Increased risk of crashing when driving.

2) Increased risk of being hit by a car when crossing the street

3) Increased risk of being robbed (at least in some countries such as Argentina)

• ... increased risk of falling off a cliff whilst texting. This happenned to my next door neighbour and she was left hobbling around on a full leg cast for nigh on a year! – WetSavannaAnimal Nov 14 '14 at 1:06
• haha, you really made me laugh! (I am sorry for her of course, but luckily she is alive!) – Wolphram jonny Nov 14 '14 at 1:10

There are no bad effects, only possibly psychological effects caused by worrying too much about the dangers of electromagnetic radiation that in reality do not exist. Note also that in much more serious cases where there is potentially a big risk due to ionizing radiation like in case of the Fukushima disaster and in Chernobyl, the main health problems in the local population was purely psychological, see e.g. here:

What is accepted by all the experts Horizon talked to is that for the victims of Chernobyl the real problem is not radiation - but radiophobia, the fear of radiation, which has caused acute psychological trauma.

• +1 The Horizon obervation is very interesting, but I'm not sure that "radiophobia" gives an accurate impression of the trauma. The word implies an irrational fear, whereas the cause of the trauma is a prolonged period of not knowing whether or not there are rational grounds for a threat that could well be real. I should imagine this would often lead to full blown PTSD. I don't think this situation is comparable to worries about moblys. – WetSavannaAnimal Nov 14 '14 at 1:03