February 14,1996. Copyright, 1996, Graphic News. All rights reserved

DANGER OVERHEAD: HYPE OR REALITY?
By Nicholas Booth

LONDON, February 14, Graphic News- Scientists at Bristol University have found what they claim is the missing link between power lines and increased incidences of cancer. A team led by Dr Denis Henshaw has found that electromagnetic fields from domestic electrical appliances can attract a shower of potentially harmful radioactive particles. In the same way that magnets attract iron filings, so electromagnetic fields tend to attract naturally-occuring radon Ð an odourless, invisible gas Ð which has been linked to increases in cancers.

Simulations of the stronger fields associated with overhead power lines suggest this may be the mechanism by which cancers can be induced. The Bristol team publishes its findings today in the ÔInternational Journal Of RadiobiologyÕ and they will reach a wider audience tonight as they are featured in Channel 4's ÔDispatchesÕ programme. It has been known for some time that there is a statistical link between close exposure to overhead power lines and certain cancers, particularly leukaemia and childhood cancers. There is, as yet, no mechanism to explain how they are caused. 

Because radon is naturally radioactive, it is unstable and prone to generate Ôdecay productsÕ radioactive in themselves and potentially carcinogenic. The Bristol team has found that these decay products attach themselves to minute particles of water and dust in the air, becoming ever more likely to stick to the skin or be inhaled. These particles seem to oscillate at the same frequency as the electricity mains supply, making them more likely to be absorbed internally. However, the Bristol physicists stress that domestic electrical equipment is unlikely to cause health problems because this phenomenon occurs only in the immediate vicinity to the equipment. 

That may not be the case for power lines, although government scientists suggest caution is warranted. The Bristol team has not made measurements around power lines in the field and the National Radiological Protection Board has called their basic idea ÔimplausibleÕ. The Board suggests that the phenomenon of radon absorption is well known and will tend to make radon decay products less dangerous because most will be deposited on walls and floors in the home and do not reach deep within the lungs. The Board suggests that although radon has been implicated in lung cancers in the home, the issue of electromagnetic fields requires separate research.

Sources: Bristol University, Channel 4, National Radiological Protection Board