Very low levels of Caesium-137 are observed in foodstuffs from time to time and arise from the trace quantities in Australian soils from global fallout up to 1974.
Australia, in common with all countries in the southern hemisphere, has received fallout from atmospheric nuclear weapons tests by several nations. Generally, fallout has been substantially less in Australia than for countries in the northern hemisphere. Monitoring since the Chernobyl accident has shown no increase in fallout deposits. Very low levels of Caesium-137 are observed in foodstuffs from time to time and arise from the trace quantities in Australian soils from global fallout up to 1974. For information on guideline levels for food, refer to pages 50-54 of the FAO/WHO Codex Alimentarius International Food Standards.
Radionuclides (normally caesium-137 and caesium-134, sometimes ruthenium-103) are measured by high resolution gamma-ray spectrometry.
Amount required
A minimum volume of 250 mL (1 cup) of material is required.
Composite samples
If directed, multiple samples can be mixed and a single composite sample analysed. In this case the result will relate to the composite sample only and does not apply to the individual samples that were mixed together to form the composite sample.
Reporting limit
Except in exceptional circumstances, the reporting limit for the analysis of the radionuclides caesium‑137 and caesium-134 in food samples will be 2 Bq/kg (2 becquerel per kilogram). This value is much smaller than any regulatory limit of which we are aware and much less than the levels of natural radioactivity in many foodstuffs. Where the customer asks that multiple samples be mixed and a single, composite, analysis is performed, the reporting limit will apply to the composite sample only.
Reports
A report will be issued normally within one week, depending on the current workload. Where the result of a measurement exceeds 2 Bq/kg, or may do so after uncertainties have been taken into account, the result will be reported together with an estimated uncertainty.
Food certificates
If requested food certificates for export purposes can be issued. Information required on the certificate must be provided by the client.
