Do pylons carry something more dangerous than electricity? 5/3/01

MATTHEW HILL:
You can't see them or feel them, but electromagnetic radiation at high level could certainly be traced this afternoon on a new estate in Nailsea near Bristol. It was built between two overhead power lines despite protests by locals.

PROFESSOR DENIS HENSHAW:
UNIVERSITY OF BRISTOL
We've been getting magnetic field levels at six times higher than those at which a doubling of childhood leukaemia has been seen. We're also getting a significant level of corona ions emission that's ionised particle emission, from these power lines.

HILL:
Until now, the Government body responsible for safety, the National Radiological Protection Board, has always maintained there's no risk to the public from overhead cables, but it's expected that tomorrow they will acknowledge a possible link with childhood cancer. They commissioned the epidemiologist Sir Richard Doll to analyse the results of other international studies. They're not prepared to talk about his findings until tomorrow, but Newsnight has discovered that, only two months ago, a bulletin from the NRPB acknowledged the validity of two recent studies from Sweden and America. They both concluded that there was a doubling of risk of childhood leukaemia in homes at high levels of exposure, that's above 0.4 micro teslas. In their bulletin of December last year, the NRPB said such levels are rarely encountered in the UK, but on this estate today, we found levels six times higher.

REPORTER:
Is that something we should be concerned about?

HENSHAW:
Well, it is implying an increase in risk of illnesses associated with these corona ions as well as the magnetic fields. I think the risk to the individual is small, but a small increasing risk applied across the whole population does imply a sizeable number of cases that might be linked to ill-health and power lines, and therefore of public health significance.

HILL:
Professor Henshaw has his own theory about the biological mechanism that may be causing cancer. He believes microscopic particles of pollution are attracted to the electromagnetic fields around power lines, and when those sticky particles, known as corona ions, are breathed in, they're more likely to cause damage. New research about to be published not only draws upon this theory, but has found a direct relationship with real power lines in the field. For the past four years, Alan Preece's team at Bristol University has been mapping overhead pylons in relation to 50,000 households in and around Avon. By adding further data from the cancer registry of deaths, he's found people living close to power lines to be 50% more likely to contract mouth cancer and up to 30% more likely to suffer from lung cancer.

ALAN PREECE:
MEDICAL PHYSICS DEPT, BRISTOL UNIVERSITY
We have to make the assumption that a large proportion of cancers must be due to pollution and items you inhale, whether it's cigarette smoke or anything else, and if the effect of these aerosols and the charging mechanism, the two mechanisms that have been suggested, are working, then they may well cause pollutant particles in the atmosphere to stick more closely as you inhale them. I think it's interesting that there is this rather larger excess in mouth cancer, which is relatively rare, but nevertheless we've found more of them than we expected downwind of these lines.

HILL:
Alan Preece's team have modified their study under the advice of Sir Richard Doll, chairman of the NRPB, but the NRPB are not talking this evening in any detail about their announcement tomorrow. One member of their team said the increase was associated with very high mains power fields, which were not usual in Britain. The National Grid referred us to a written statement put out by the Electricity Association. It said:
"We would be extremely surprised if the report did indeed state that either power lines or the electric and magnetic fields they produce were now known to be a cause of childhood cancer." But in a reference to the American and Swedish studies, they did admit that:
"there remains some uncertainty about the very highest fields, experienced by around one in 250 children in the UK." They stress the evidence falls short of establishing cause and effect. On this estate, it's hardly surprising there are heightened sensitivities about the issue of electromagnetic radiation. In Sweden, you wouldn't see a landscape like this, as cables there are buried deep under ground and it's unlikely that planning permission would be granted for this type of estate. But even if these measures were introduced in the UK, it would be too late for thousands, and phenomenally expensive. One thing everyone agrees with, including the Department of Health, is the urgent need for further research.