Effect of mobile phone signals on health

Based on available scientific evidence, radio waves from mobile phones and base stations are probably not a significant threat to health.

The only known effect of low level radio waves from mobile phones is that of heating. Such an effect is not a threat to health, just as body heating from other sources, including sunshine or home heaters, is not.

It must be noted that mobile telephony waves are a non-ionising form of radiation. Whereas ionising radiation, such as gamma rays and X-rays, may cause chemical changes in living organisms, non-ionising radiation does not.

The justification for setting limits to exposure is to avoid excessive heating. For the head and trunk, the limit set is 2W/kg. Most hand sets are well within this limit. For base stations, the exposure to non-ionising radiation is a fraction of this amount and, hence, the heating effect is negligible.

Various experiments have been carried out including studies of a large sample of the population, studies on mice and in vitro studies. Some studies focused on the possibility of non-ionising radiation in inducing cancer - this being the primary concern of the public. For live cells subjected to non-ionising radiation, no changes to the DNA or to chromosones were observed.

A study was also carried out whereby mice ate less than normal because of the heating resulting from the non-ionising radiation. No other effect on health was observed. Complaints have been received relating to fatigue, lethargy, sleep disturbances and headaches but no direct link could be established between these symptoms and exposure to non-ionising radiation.

It ought to be pointed out that studies have to be carried out in a rigorous scientific manner if they are to provide any conclusions.

Research programmes are underway in a number of countries to fill gaps in knowledge and so help to make a more complete assessment of any risk to health.

Having said that, it is really up to society to decide on whether to adopt a precautionary principle - scientists can only give the conclusions derived from research.

The above are highlights from a presentation made by Dr Sienkiewicz, from the National Radiological Protection Board of the UK, at an event organised by the Malta Group of the Professional Engineering Institutions, in collaboration with the Institution of Electrical Engineers - UK.

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