Families living under electricity cables are concerned about their children's health after research carried out in Oxford showed that high voltage wires may cause childhood cancer.

Scientists at Oxford University have published a study stating that youngsters living within 200m of overhead power lines when they are born have a 70 per cent increased risk of developing leukaemia compared to those living more than 600m away.

Their results -- the largest study of its kind -- suggest that five out of every 400-420 cases of the illness are connected to electricity cables.

But the research team, led by Gerald Draper, an honorary senior research fellow at the university's Childhood Cancer Research Group, point out that biological work needs to be done to prove their findings.

The results have prompted the electricity industry to start discussions about possible changes to the safety limits of power lines with the Government and regulators.

The study has caused concern among parents living in Ladygrove, Didcot, where cables from the nearby power station overshadow the housing estate.

Mother-of-two Elaine Connolley, 34, lives in Synderford Close with her children Samuel, 14, and Ellie-Jean, one.

She said: "I've always worried about why the cables were not put underground, like they are in Scotland.

"We're actually moving in a couple of weeks and it's a bit of a relief."

Claire Brown, 26, of Washford Glen, said she was not happy about moving to her home with children Natasha, five, and Tyler, three.

She said: "I moved to Didcot because of my husband's work and we got put here by the council.

"I've never seen so many power cables in one housing development."

One in every 2,000 children develops childhood leukaemia, which affects the blood. In Oxfordshire, there were seven new cases in 2000-2002.

Researchers have investigated a variety of possible links, including genetics and electromagnetic fields.

Scientists have been concerned since 1979 about the link between cancer and power cables, which produce low frequency electric and magnetic fields.

Mr Draper and his team looked at 29,000 children under 14 with cancer, and compared them to a group of youngsters individually matched for gender, date of birth and where they were born.

They calculated how far each child lived from the nearest high voltage power line, and found those who lived within 200m were most at risk.

There was also a slight increased risk for those who lived 200-600m from the cables. Mr Draper said: "The most obvious explanation of the association with distance from a line is that it is indeed a consequence of exposure to magnetic fields.

"We have no satisfactory explanation for our results in terms of causation by magnetic fields and the findings are not supported by convincing laboratory data."

Dr John Swanson, scientific advisor to the Energy Networks Association, said: "The study strengthens the evidence that childhood leukaemia rates are slightly higher near power lines, but leaves the question of what causes this more confused than before."