Optimisation of enrichment methods and evaluation of errors for high sensitivity measurement of 222Rn in natural waters

  • H. MartindaleEmail author
  • U. Morgenstern
  • R. Singh
  • B. Stewart


Radon-222 (222Rn) is increasingly being used to measure and map groundwater-surface water interactions in natural waters. However, the direct measurement, without prior enrichment of 222Rn, allowing for a lower limit of detection of 0.2 BqL−1 is not sensitive enough to study 222Rn concentrations in the water close to or below 0.2 BqL−1. 222Rn enrichment prior to measurement, to increase the number of measured 222Rn decays, enables for improved measurement sensitivity. Here we show the influence of every parameter of 222Rn measurement and enrichment to enable optimisation of the 222Rn measurement.


Environmental isotopes Liquid scintillation counting Radon measurement Isotope enrichment 



Martindale was affiliated with GNS Science at the time this work was undertaken and is currently affiliated with the Ministry for the Environment in New Zealand.


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  1. 1.GNS ScienceLower HuttNew Zealand
  2. 2.Ministry for the EnvironmentWellingtonNew Zealand
  3. 3.Institute of Agriculture and EnvironmentMassey UniversityPalmerston NorthNew Zealand

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