An expert report for a Department of Health advisory committee on radiation has found a marked increase in liver and blood cancers close to the site of the contamination, the Sunday Herald can reveal.
The scientists have recommended an investigation into potential links between the radioactive site and cancer levels.
The report pointed out that liver cancers were concentrated in communities near the polluted foreshore. This "reinforces the suspicion" they were linked to the discarded radium that has littered the area for decades, the report said.
Yesterday, the revelations provoked concern among local residents, who demanded an in-depth inquiry. They were backed by their local MP, former prime minister Gordon Brown, who also called for further investigation. The MP for Kirkcaldy and Cowdenbeath told the Sunday Herald last night: "Local residents will rightly want and expect more detailed studies done with the greatest of precision to reassure them about their safety."
Last month, the UK Government's Health Protection Agency (HPA) issued advice that public health risks from radiation at Dalgety Bay were low.
But this has now been undermined by the report for the Committee on Medical Aspects of Radiation in the Environment (Comare), which advises ministers in Westminster and Holyrood.
The "Preliminary Report on Cancer Rates around Dalgety Bay" was presented to Comare's last meeting on October 10. Its findings were released to the Sunday Herald in response to a request under freedom of information legislation.
The report revealed there has been a statistically significant excess of liver cancers around Dalgety Bay between 2000 and 2009. Instead of the four cases that would be expected, there had been 10.
All cases were found in the "data zones" nearest the contaminated foreshore. There was "a pronounced tendency for the observed cases to be close to the headland", the report concluded. "It is recommended that there should be further investigation of these cases and an analysis of earlier data if available."
There was also a significant excess in lymphomas (cancers of white blood cells), the report said. There were 27 cases around Dalgety Bay, where 16 would have been expected.
Alex Elliott, a Glasgow University physics professor who chairs Comare and an expert group on Dalgety Bay, accepted there was a possibility the liver cancers were linked to the contamination, but stressed there could be other causes.
"While exposure to radium cannot be excluded as a cause, there are other risk factors more closely associated with this disease," he said.
Comare is now conducting further investigations with the aim of producing a final report next year. Elliott has previously been critical of the HPA's reassuring line on public safety.
Colin McPhail, chairman of the Dalgety Bay and Hillend Community Council, said he was concerned about the findings. "There should be a detailed investigation by NHS Fife," he said. "The local residents are owed that."
The Scottish Environment Protection Agency (Sepa) pointed out that some of the particles found at Dalgety Bay could pose a "significant hazard" to people who encountered them.
"We believe that the public should be protected from such an encounter as far as is practical," said Sepa's radioactive substance specialist, Dr Paul Dale.
"While there continues to be uncertainty about the risks, Sepa believes that it needs to be precautionary in its approach and will continue to act to protect the public and the environment, when there is a significant possibility of harm."
The HPA defended its advice that public health risks were low, and was backed by the Ministry of Defence (MoD), which many people blame for the contamination. "The MoD continues to assist Sepa on a voluntarily basis without prejudice to determine the scope of any action," said an MoD spokesman.
The Scottish Government promised to work with other agencies to investigate whether there was an elevated heath risk. A spokeswoman said: "We fully appreciate the considerable anxiety this long-running issue has caused the local community and hope the MoD continues to deal with this as a matter of urgent concern."
Radioactive contamination was first discovered at Dalgety Bay, a popular sailing resort, in 1990. It is thought to come from radium used to illuminate the dials of aircraft disposed of in the area after the second world war.
More than 2500 radioactive hotspots have been found on the foreshore in the past 22 years, more than 1000 since September 2011. They have ranged in size from tiny specks to lumps as big as half-bricks and include some of the most lethal found on public beaches.
Parts of the foreshore have been closed for the past year and an official ban on harvesting shellfish has also been put in place.
An investigation into the contamination is under way.