Do you ever get scared that cell phones and WiFi signals are giving you cancer/causing harm?

ABSOLUTELY!!!

This is a valid question and concern that everyone should be aware of as the longer you use the phone the greater the adverse affects are likely to be and certainly use of phones by young children should be avoided altogether, due to their skull and brain is still developing.

Although there is no proof to indicate that mobile phones can cause cancer, there is sufficient debate to cause doubt as to the relative safety. The thing is, it is a mutlibillion dollar industry and it will not be quashed without definite proof, which may not arise for some decades. As a telecommunications engineer I am aware of the power density levels produced by mobile phones and the effect they can have on different people.
Mobile phones transmit using radio frequency radiation (RFR). Dependant on the network this can range between 800MHz and 2GHz. These are radio waves located within the electromagnetic spectrum. X-rays which are known to cause cancer through ionizing radiation are also within the electromagnetic spectrum, however, RFRs cannot cause cancer in the same way as x-rays because RFRs are non-ionizing.

However, high levels of RFRs can cause health effects through heating the human body (thermal effects). To address this health effect, the Radiocommunications (Electromagnetic Radiation Human Exposure) Standard 1999 specifies limits on public exposure to RF radiation from mobile phones. The limits set by this Standard are only a fraction of the levels needed to cause thermal effects.

Whilst it cannot be shown at this point in time that the thermal effects from mobile phones are a health hazard there is a considerable body of scientific literature which describes the effects of RFR in biological systems that cannot be directly attributed to heating. These effects are referred to as non-thermal and have been demonstrated to cause alteration in animal behaviour, or changes in the functioning of cell membranes.

To limit the possible adverse effects mobile phones may have I would suggest that anyone concerned about their use should;

- Limit the prolonged use of mobiles to under a couple of minutes at a time.
- Use the phone in handsfree speaker mode.
- Avoid using the phone in a confined space (such as in the car or building) as this causes the phone to radiate at the higher power levels to get a signal out.

Personnaly I avoid using the phone as much as possible and if I need to use it I keep it under a few minutes or use hands free.