Radiochemical determination of lead-210 in environmental water samples using Cerenkov counting

A relatively simple method has been developed for the determination of210Pb via its β-emitting daughter,210Bi. Lead-210 was separated from interfering elements as lead sulphate. The precipitate was dissolved in an alkaline solution of EDTA and the Cerenkov signal produced by the build-up of210Bi was counted 30 days after storage using tritium channel of a liquid scintillation counter. Cerenkov counting efficiency was found to be approximately 20%. A lower limit of detection of 5.1 mBq/1 (based on 3σ of the background with 500 minute counting time) was achieved. Chemical recoveries in the range of 70–100% were determined gravimetrically. Interference associated with currently used methods is avoided. Data from from both spiked samples and natural samples are presented.