Investigation of radioactive lead, uranium, and thorium in environmental waters by extraction chromatography resins

Abstract

A time-saving and sensitive method for monitoring low concentration (activities) of ²¹⁰Pb, ²³²Th, and ²³⁰Th and ²³⁸U, ²³⁴U, and ²³⁵U in water samples has been developed. Through the combination of co-precipitation and extraction chromatography by 3M RAD disks and UTEVA (Eichrom) columns effective radiochemical separation of the analytes was carried out. Thorium and uranium activities were determined by alpha spectrometry and lead activity by LSC, respectively. The minimal detectable activities obtained were 0.6 Bq m⁻³ for uranium, 0.29 Bq m⁻³ for thorium, and 2.5 Bq m⁻³ for ²¹⁰Pb. More than 150 different waters were analysed for uranium content and only 30 for lead and thorium. The investigations are still in progress.

Keywords:

• Extraction chromatography
• Natural radioactivity
• Water

Acknowledgements

We are grateful to ‘Service Géologique’ of Luxembourg and Harald Hofmann for the sample collection and geological help for our analysis.