Monday, 10 October 2011

Radium contamination of Dalgety Bay in Scotland

Since the discovery of radium contamination on the beach at Dalgety Bay in Scotland in the early 1990s there appears little evidence that the problem has been properly addressed and the source of the contamination removed preventing the re-population of the beach with highly radioactive fragments of radium.  SEPA in their recently published report concluded that :- 

“Work undertaken by Defence Estates has confirmed the typical number, size and
activities of point sources at Dalgety Bay. It has also shown that the beach area
continues to re-populate with high activity point sources once cleared and that it is
estimated that over a year these will number about 100 in total. Thus there remains a
hazard to the public at Dalgety Bay from these point sources, and the total number of
radioactive sources at Dalgety Bay remains unknown.

Based on the results of solubility testing, indicative committed effective doses could
range up to 128 mSv for a 3 month old infant, with the majority of the dose being from radium daughters. However, the 2010 work has indicated that the solubility of these sources may be greater than previously expected (25% rather than up to 15%). Doses could also be greater if the relatively small number of samples subjected for leaching was not representative of the population as a whole. Overall our 2006, 2009 and this 2011 report have shown that several of the sources recovered from Dalgety Bay could give committed effective doses in excess of the relevant value for some age groups, prescribed in the Statutory Guidance issued to SEPA by the Scottish Government for Radioactive Contaminated Land.

Direct measurements of point sources to determine potential skin doses have been
undertaken. The results have been reported separately which indicate that it is unlikely the dose rate from the Dalgety Bay sources could exceed the relevant criteria specified in the guidance issued to SEPA by the Scottish Government for Radioactive Contaminated Land.

The potential committed effective doses from Dalgety Bay point sources remain
significant. The primary pathway of concern is via ingestion and as any potential effects (e.g. cancer) may take many years to be expressed and be unlikely to be easily attributable to an exposure from a visit to Dalgety Bay.

The locations and suitability of the current signage, as an optimal intervention measure, should be reviewed. Given the numbers of people using the beach there is also a need for an ongoing monitoring and recovery programme to reduce the hazard present on the beach. In the longer term, as radium has a half life of 1600 years, a programme of work to determine the primary source of the contamination at Dalgety Bay beach and isolate it from the environment may be the only manner in which the level of contamination can be reduced to a negligible level where no further interventions are needed. Given the potential costs involved of developing any robust risk assessment this approach to isolate the contamination from the environment may be the most cost effective approach to mitigating the contamination in the long term. 

The absence of any programme to isolate the radioactive contamination at source will mean that sources which pose a significant hazard to health will continue to be present on the beach at Dalgety Bay. It is concluded that a programme to identify the primary source or sources is needed to reduce the number and hazard of these sources to the public using the beach at Dalgety Bay. “

A point to note is that a recent Press report indicates that material from the beach has been used in children’s sandpits; I do not believe that the risk assessments took account of this possibility.

The Committee on the Medical Effects of Radiation (COMARE) has been tasked to provide advice on the health effects of radium exposure at Dalgety Bay, but has yet to publish its findings.

“Dalgety Bay
The appearance of radium particles at Dalgety Bay first came on the committee’s work programme back in 1990. The discovery of much smaller particles recently has seen this item reappear for further consideration. A site visit by members of the Dounreay Working Group was carried out on 13th May 2008. The committee is continuing to liaise with the MoD and SEPA on this matter. The committee will also be kept aware of other similar contaminated sites as and when issues arise.”

Background information about the historic use of radium by the Ministry of Defence and the problems this created with regard to contaminated land can be found in a report by RWMAC dating back to 2000.

Most recent Press articles as of October 2011
I find it most surprising that after 20 years the beach still  remains contaminated and a significant risk to those who use it; that SEPA, has so far failed to make the “polluter pay”  to clean this contamination up and make the beach safe for unrestricted use. The present publicity relates to the beach little has been said about the potential contamination inshore from the beach.

In response to the press reports the MoD insisted that it took safety very seriously. “We have yet to see the latest findings from SEPA,” said a ministry spokeswoman. “Should significant risks present themselves then SEPA  has the necessary statutory powers to address these.”

This shows how the MOD is doing its best to wash its' hands of this issue and leaving it to others to clean up, so much for MOD saying it takes safety seriously

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