The re-emergence of evidence that Sellafield’s plutonium is found in children’s teeth has brought the expected response from British Nuclear Fuels and Sellafield’s pro-nuclear Member of Parliament Dr Jack Cunningham. Both have ventured that the plutonium might have come from nuclear weapons fallout rather than from Sellafield’s reprocessing operations. Whilst it suits BNFL’s purpose to deflect attention away from its reprocessing plant and towards nuclear weapons fallout, there is little evidence to support their suggestion.
A 1997 report commissioned by the Ministry of Health showed that children living close to Sellafield had twice the level of plutonium in their teeth as children living 140 miles away. The research, undertaken by Dr N.D.Priest, then of the Atomic Energy Authority’s ’s biomedical research department at Harwell, was reported in The Science of the Toatl Environment 201 (1997) 235-243 and also in the News Scientist Journal (2.8.97). The recent resurrection by the Sunday Observer newspaper of the original report has prompted questions to be raised in the House of Commons.
Current claims by Health Minister Melanie Johnson, siezed upon by BNFL, that the minute levels of plutonium found in teeth ‘are no risk to public health’ have been challenged by a leading expert on blood disorders. Professor Eric Wright of Dundee University says that even tiny specks of plutonium might cause cancer. Other critics have stated that even if there was little risk from plutonium in the dead tissue of tooth enamel, its presence during the formation of tooth enamel would indicate a parallel inclusion in bones where the potential for harm is much greater.
Evidence of BNFL’s overwhelming contribution to general plutonium levels is well documented. Weapons fallout is small by comparison and can be positively distinguished from Sellafield’s material by its isotopic fingerprint. In the late 1980’s, an analysis of samples of house dust taken from houses along the West Cumbrian coast showed levels of plutonium from Sellafield significantly raised over fallout level. In one house the level was almost 1000 times higher than fallout. Other research has shown that along the coastal strip as a whole, levels of Sellafield’s plutonium in grassland samples (from the top 15cm of soil) represent a 100% increase over fallout levels.
That this highly toxic, carcinogenic and long-lived material, deliberately discharged by BNFL from the Sellafield site, is found in any part of the human body is hardly surprising. A study on autopsy tissues by the National Radiological Protection Board (NRPB) in 1986 revealed that a number of Sellafield workers had varying concentrations of plutonium in their bodies – in one case 600 times higher than in the general population. Even locals who did not work at Sellafield were found to have 50%-250% higher plutonium levels than the general population.
The presence of BNFL’s plutonium legacy is readily identified in the local environment where river estuary samples show Plutonium 239 & 240 (Pu239 &240) to be present at a level of almost 7000 Bq/kg. A recent study by University College Dublin showed that plutonium contamination of the Solway Firth north of Sellafield was 100 times greater than previously thought. The report also confirmed earlier studies which has shown how, through storm and tidal action, plutonium deposits on the sea bed around Sellafield’s discharge pipeline are driven shorewards and concentrated in sea spray. On land the dried out dust particles are resuspended in air and become available for human intake via inhalation and ingestion. It is estimated that over half a ton of plutonium has been discharged from Sellafield into the Irish Sea over the last 50 years. Pu 239 has a radioactive half-life of 24,000 years, Pu 240 6,500 years and Pu 241 14.4 years.