A sample of about 1080 kg of mussel (Mytilus galloprovincialis species) was collected in Anse de Carteau, Port Saint Louis du Rhône (43°20”S, 5°10’E), France, by the Institut de Radioprotection et de Sûreté Nucléaire (IRSN, France) in June 2003. The shells were removed and the fresh soft parts (145 kg) and internal fluids (505 kg) were separated from the raw mussels. The sample was reduced by freeze-drying to about 60 kg, finely ground to a powder, sieved at 200 μm, and homogenized in a nitrogen atmosphere. The samples were bottled in brown glass flasks under nitrogen gas, sealed with polyethylene caps and labeled with the code IAEA-437. The bottles containing 200 g of mussel powder each were sterilized according to ISO standards at 25 kGy in an irradiation facility.
This Certified Reference Material is intended to be used for quality assurance purposes in the determination of radionuclides in mussel samples, including development and validation of analytical procedures, preparation and testing of reference methods, quality control, and training of analysts. This material is not to be used as a calibrator.
Certified values for massic activities (Based on dry mass)
Reference date for decay correction: 01 November 2003
| Radionuclide | Certified value [Bq kg-1] | 95% Confidence interval [Bq kg-1] |
| 40K | 373 | 360 - 380 |
| 234U | 2.3 | 2.2 - 2.4 |
| 238U | 1.87 | 1.80 - 1.92 |
| 239+240Pu | 0.0076 | 0.0071 - 0.0082 |
Information values for massic activities (Based on dry mass)
| Radionuclide | Information value [Bq kg-1] | 95% Confidence interval [Bq kg-1] |
| 137Cs | 0.14 | 0.11 - 0.23 |
| 210Po(210Pb)* | 4.2 | 4.0 - 5.4 |
| 226Ra | 0.27 | 0.21 - 0.31 |
| 228Ra | 1.48 | 1.00 - 1.80 |
| 228Th | 0.79 | 0.71 - 0.96 |
| 230Th | 0.16 | 0.15 - 0.40 |
| 232Th | 0.11 | 0.09 - 0.16 |
| 235U | 0.09 | 0.07 - 0.11 |
| 241Am** | 0,020 | 0.008 - 0.034 |
* 210Pb and 210Po are considered to be in equilibrium
** The values should be corrected for in-growth from 241Pu
The assigned values were established on the basis of statistically valid results submitted by 26 laboratories, including expert laboratories, which had participated in an international interlaboratory comparison organized by the IAEA Environment Laboratories, Monaco.
The details concerning all reported results as well as the criteria for qualification as a certified or information value may be found in the respective report (attached).
