Overhead power lines do not represent a significant risk to human health, despite two studies that have linked them to childhood leukaemia cases, according to a British expert on the issue.
Dr Mike Crumpton last night discussed the extensive research effort under way to measure health hazards associated with overhead power lines during a public information lecture at Trinity College Dublin.
A trustee and scientific adviser to a UK charity funding research into the issue, Dr Crumpton acknowledged the need for more research to address health questions raised by two independent studies published in 2000. Both suggested a small increased risk of leukaemia in children exposed to the electro-magnetic fields (EMF) that surround power lines.
The health hazard was very small, possibly accounting for two of the 500 leukaemia cases diagnosed each year in the UK, he said.
While the epidemiological risk was low, these two extra cases represented a tragedy in human terms. For this reason, a great deal of time, effort and money was being spent on research into health effects from power-line EMFs.
One of the key problems was finding a causal link between the fields and human disease.
"In scientific terms there is no known physical mechanism for such a weak magnetic field producing a biological response," he said during the Academy Times lecture, organised by the Royal Irish Academy, The Irish Times and DEPFA Bank.
He advises the UK EMF Biological Research Trust, a body funded by donations from National Grid Transco plc, the company that owns the high-voltage electricity transmission network in England and Wales. The trust, in turn, supports independent research groups looking at EMF health hazards.
He accepted that using funding from the electricity industry allowed opponents to dismiss research findings supported by the trust.
An independent scientific advisory committee oversees the research, however, so it could not be influenced by the industry, he said.
"The epidemiological studies are no more than indicative, and unless we underpin them with a good scientific mechanism, then we should not do anything in response to the epidemiological studies," Dr Crumpton stated.
"I do not think there is a satisfactory scientific case for putting power lines underground or moving people out of houses near power lines," he added.
The health risks associated with moving heavy furniture, the stress and the hazards of driving to a new home probably made moving a greater danger to health than remaining in a house near a power line, he said.
A former director of laboratory research at the Imperial Cancer Research Fund, Dr Crumpton is a leading researcher into cell mechanisms and chairs the scientific advisory committee of the Breakthrough Breast Cancer charity.
The lecture is available at www.ria.ie