Does electromagnetic energy cause cancer?

No one knows for sure if electromagnetic fields (EMF) do cause cancer. Research has looked into the electromagnetic radiation (EMR) caused by power lines as a possible cause of leukaemia. But as yet no conclusive link has been found.

A report in 2001 from the National Radiation Protection Board (NRPB) showed that there may be a very slight increased risk for leukaemia in children. The electromagnetic radiation talked about in this report was mostly from domestic use of electricity. 20 out of every 100 homes (20%) with high level magnetic fields were close to pylons or overhead power cables. The high levels in the other 80 out of every 100 homes (80%) were the result of the electricity supply in the home. Out of 500 cases of childhood leukaemia the risk from electromagnetic fields might add another 2 cases a year. Over two years, 1 of the 4 extra cases would be related to overhead power lines.

A study in 2005 looked at how close children lived to high voltage power lines when they were born. The aim of the study was to find out if this affected their chance of getting leukaemia. It found that children who lived within 200 metres from these lines had an increased risk of getting leukaemia. It also showed a smaller increase in risk for children living between 200 and 600 metres from these lines. This would mean that up to 5 cases of childhood leukaemia per year could be related to overhead power lines. But these results are not straightforward. No one can say for sure if living close to high voltage power lines increases the risk of leukaemia, and even the researchers say these results could be due to other factors or chance.

In 2005, the NRPB became part of the Health Protection Agency, as the radiation safety division. In 2006 their Advisory Group on Non Ionising Radiation (AGNIR) looked into the evidence on electromagnetic radiation and breast cancer risk. The theory was that exposure to electromagnetic fields could lower levels of a hormone called melatonin and that this could increase risk of breast cancer. After looking at all the available evidence, the group said that exposure to electromagnetic fields did not appear to increase risk of breast cancer. And that EMF exposure didn't appear to affect melatonin levels either.

A Danish review of studies published in 2008 looked at electromagnetic fields and childhood leukaemia. The review stated that children exposed over a long time to electromagnetic fields do seem to have a slightly increased risk of leukaemia. But scientists cannot explain why and it could be due to chance. Some studies in Australia and Italy have reported childhood leukaemia clusters close to high power radio and television broadcast transmitters. But recent, large, well designed studies in Korea and Germany show no such effect.

Mobile phones give off radiofrequency energy. Radiofrequency energy is a form of non ionizing electromagnetic radiation. Currently, there is no consistent evidence that non ionizing radiation from mobile phones is associated with cancer risk. The World Health Organisation say that the electromagnetic fields produced by mobile phones are classified by the International Agency for Research on Cancer as possibly a carcinogen in humans. And that studies are ongoing to fully assess potential long term effects of mobile phone use. The WHO also say that a large number of studies have been done over the past twenty years to assess whether mobile phones pose a potential health risk. So far no adverse health effects have been found as being caused by mobile phone use. Mobile phones were not used widely until the early 1990s and so longer term effects are not yet known. Animal studies of long term exposure to electromagnetic fields have not shown any increased cancer risk.

There are gaps in our knowledge of all these areas and research is likely to continue. But it seems unlikely that electromagnetic fields cause cancer. If there were strong links, they are likely to have shown up in the research that has been done so far.