BEFORE the dangers of radiation poisoning were discovered, radium-226 was routinely used to manufacture the luminous paint needed to make aircraft dials glow in the dark for pilots.

Young women working in factories were known to lick the bristles on their paintbrushes so that they would form a point that made it easier to apply the fine lines and numbers.

The resulting ingestion of radioactive radium caused cancers and disintegration of their jaw bones, similar to 'phossy jaw'.

Although the hazard was eventually recognised in 1925 and incidence of radium-induced osteonecrosis largely eradicated by 1950 as phosphorescent- or tritium-based light sources replaced it, the deadly reputation of radium persists.

READ MORE: MoD admits old war planes contaminated Dalgety Bay

In Scotland, it has become synonymous with Dalgety Bay in Fife, where particles of radium-226 from incinerated old military planes were first discovered on a stretch of coastline near the Sailing Club in 1990.

They are believed to have been dumped there before 1959 by the nearby HMS Merlin airbase, which was involved in the servicing and disposal of aircraft fitted with parts luminised with radium paint.

In 2011, restrictions were put in place to fence off the area after particles were found with "significantly higher" radioactivity than those previously identified.

This sparked fears that local residents could have been exposed to dangerous levels of radioactivity, increasing their risk of developing certain cancers.

In 2014, a report by UK Government advisers at Comare (the Committee on Medical Aspects of Radiation in the Environment) warned that contamination in the popular walking spot posed "a potential risk to public health".

The same report initially concluded that the incidence of two specific forms of cancer - non-Hodgkin lymphoma and primary liver cancer - was higher than expected during the period from 2000 to 2009.

However, a clinical review subsequently concluded that it was "very unlikely" this was linked to radium-226. In any case, non-Hodgkin lymphoma is rarely caused by radiation exposure, and liver cancer only "occasionally" associated with it.

Now the most comprehensive analysis of the area's cancer statistics to date by ISD Scotland has found "no significant increase in overall cancer risk" for those living in any part of Dalgety Bay.

READ MORE: Dalgety Bay awash with radioactive military waste - but MoD refuses to clean it up 

Even for cancers with a known link to radiation, such as myeloid leukaemia, thyroid cancer or female breast cancer, no significant increased risk was found.

Between 2008 and 2017, 113 people in the area were diagnosed with one of these three cancers. That compared to a predicted number of 104 cases, based on an analysis of the population's age, sex and socioeconomic profile.

The discrepancy was not considered to be statistically significant enough to be definitively linked to radiation exposure as opposed to chance, however.

There were nine cases of liver cancer, compared to a predicted 7.6, and 65 cases of lung cancer - also occasionally associated with radiation compared to a predicted 55.

However, the incidence of all the other forms of cancer known to be caused at times by radiation exposure, were lower than expected.

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There were a total of 92 cases of brain tumours, stomach, colon, oesophagus, bladder or ovarian cancer compared to the 106 predicted by the ISD Scotland modelling.

The report states: "Cancer incidence - or risk - was not significantly higher than the rest of Scotland overall, nor was it significantly higher in any individual group of cancers.

"This includes the two types of cancer (liver and non-Hodgkin lymphoma) that were found to have a higher than expected incidence in the previous report (2000-2009)."

The statisticians divided Dalgety Bay into 13 datazones based on cancer records and postcodes, but added that "none of the cancer sites showed evidence of a significantly higher than expected incidence rate".

The report was commissioned by Comare as a follow-up to a previous ISD Scotland data collection which had looked at cancer incidence in the area between 1975 and 2009, and found no elevated rates.

However, yesterday's report did admit that it is difficult to rule out the risk altogether given the likely delay between radiation exposure and cancer onset, and the probability that many residents will have moved in and out of the area over the decades.

It said: "The period of time between exposure and the diagnosis of cancer, and the mobility of the population, mean that a true association might not be apparent.

"Some exposed individuals may have moved elsewhere before a cancer was diagnosed, but conversely, some individuals may have just moved into the area and not been exposed to any local risk factors yet have been diagnosed with cancer."

Meanwhile, a Ministry of Defence action plan to cleanse and contain the site, which was delayed this summer reportedly due to Brexit, is now expected to be carried out in 2020.