Note: This article has been updated / corrected as of 9am Tuesday 16th August.
What is Electromagnetic Radiation?
Radiation is a form of energy that emanates in waves. It is emitted from a variety of sources such as radio & television transmission towers, the sun and X-ray machines (refer diagram below). Electromagnetic Radiation (EMR) has electric and magnetic components and travels at the speed of light (300,000 kilometres / second). One of the classic ways of categorising radiation is to distinguish between ionising and non-ionising radiation. Ionising radiation (for example X-rays or gamma rays from radioactive material) is small in size, penetrates easily and is powerful enough to strip electrons off atoms. It is well established as cancer causing. Some research is also pointing to a number of negative health effects from non-ionising radiation, including possibly cancer. Below is the entire spectrum of radiation illustrated: Electromagnetic radiation was first understood by physicists in the late 1800’s and has been since harnessed in all manner of medical, communications & heating technologies.
Mobile phones use microwave radiation to operate.
Mobile phones use electromagnetic radiation travelling at the speed of light to carry sound to mobile phone base station antennas. In Australia the frequencies used for these signals are between 700Mhz and 2.1Ghz (2100Mhz). These frequencies belong to the range of frequencies known as microwave radiation. It is this type of radiation that is also used in microwave ovens (2.4Ghz). However while microwave ovens operate at up to 1,000 watts of power and base stations between 25 and 60 Watts, mobile phones operate below 2 watts (3G and UMTS phones).
Cell phone radiation is absorbed by the head and body.
Mobile phones transmit microwave radiation from a point within centimetres of the brain. The radiation emitted is powerful enough to reach a base station sometimes up to a few kilometres away, even passing through buildings to enable a call. This radiation also penetrates into the head, hand and body. The government measure used to estimate the amount of radiation absorbed is called S.A.R. (the Specific Absorbtion Rate). It is estimated by a leading Australian bioeffects researcher that localised brain temperature increases by as much as 0.1 of a degree as a result of mobile phone use. While the body’s natural heat dispersion capabilities can manage this, some questions remain over other health effects.
We live in a sea of radiation so what’s the big deal?
Modern cities are as flooded with artificial forms of radiation as we are to daylight. Wherever you are that receives mobile phone, radio or television reception you are being exposed to weak electromagnetic radiation. Digital wireless systems (data communication networks and Bluetooth [2.4Ghz]), also produce similar radiation. Most of our exposure to this radiation comes from far away transmission antennas and is continuous. Radiation from these sources penetrates buildings, irradiates the whole body and exposes an entire community. Power levels however drop dramatically the further you get away from a base station and are very low. There are concerns in some quarters that this constant low level electrical bombardment impacts public health but such effects are not widely recognised.