There is categorically no evidence that living near nuclear power stations increases the rate of childhood cancers, says a report.
The research is the largest to date
The Committee on Medical Aspects of Radiation in the Environment based its conclusions on data on 32,000 childhood cancer cases from 1969-93 in the UK.
Overall, children living within a 25km radius of a site were no more likely to get cancer than those living elsewhere.
However, there was a cluster of cases close to the Rosyth nuclear dockyard.
There were slightly more cases of leukaemia and non-Hodgkin lymphoma within the immediate vicinity of the Rosyth site than was expected, which conflicts with previous studies of this nuclear installation.
The authors said there were many possible explanations for this other than radiation and recommended more research as soon as possible.
Past and the current data show similar clusters close to other nuclear (but non-power station) sites, such as Aldermaston, Burghfield and Harwell in the area of Berkshire and South Oxfordshire.
The latest research is the largest study so far looking at the cancer risk posed, if any, by power stations.
Professor Bryn Bridges, chairman of COMARE during the preparation of this, its 10th report, said: "We think this is as definitive a study as one can do.
"There is no evidence from this very large study that living within 25km of a nuclear generating station in Great Britain is associated with any increased risk of childhood cancer."
"We can give power stations a clean bill of health," said Professor Bridges.
Critics maintain power stations do pose a cancer risk.
Chris Busby of Green Audit, an environmental consultancy and review organisation, said: "By looking at a 25k radius they are not dealing with the actual real world movement of radioactivity from power stations to people.
"The wind blows in particular directions and the materials are released into the environment in particular ways. Much of it ends up in the sea and the coastline. We have told them this. These radial studies are meaningless.
"Also, they should be looking at adult cancers, particularly female breast cancers, as well.
"Childhood leukaemia is a rare disease and the numbers involved are going to be so small that it is much more difficult to get the levels of statistical significance that you need to see an effect."
But Professor Bridges said it was better to look at childhood cancers because children were more sensitive to the effects of radiation and they were less likely to have moved around a lot geographically, making it easier to check for any link.
A spokesman from the Department of Health said: "It is important to reassure the public that this research found no evidence of an excess of cancer cases around any of the nuclear power stations in the UK.
He said that although there was no evidence of a causal link for cancer clusters around nuclear sites, other than power stations, the department recognised it was an important issue.
"The department has an ongoing programme of radiation protection research set up to address these issues," he said.
Cancer Research UK's Professor John Toy said: "We are extremely pleased that this report found no evidence for an excess number of cases of cancer in children who live near nuclear power stations.
"However, the excess incidence of certain childhood cancers near some types of nuclear installation sites remains a real worry.