"We found that the overall rates of cancer and mortality in general were fairly similar amongst those who took part in the tests and those who didn't," Dr Colin Muirhead, of the NRPB, said in an interview.

"But there is still some suggestion there may be a raised risk of leukaemia, other than chronic lymphatic leukaemia (CLL), among the people who took part in the tests," he added.

CLL is a type of leukaemia which is not thought to be induced by radiation.

Muirhead and his colleagues followed up the two groups from 1952-1998 to determine the impact of their exposure on the development of cancer. They said their findings were in line with results from earlier British and American research.

"There is some degree of consistency with other studies," said Muirhead, who reported the results in the journal Occupational and Environmental Medicine.

The veterans who participated in the nuclear testing had various jobs. Some flew over test sites, others were involved in decontamination procedures. But the scientists said they found no indication that a particular job was associated with any difference in cancer risk.

Leukaemia is a relatively rare cancer of the white blood cells. Like most cancers, scientists believe people may have a genetic predisposition to the disease that makes them vulnerable to exposure to cancer-causing agents. The period between exposure to the development of symptoms is up to 10 years.