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

A time-saving and sensitive method for monitoring low concentration (activities) of 210 Pb, 232 Th, and 230 Th and 238 U, 234 U, and 235 U 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 0.6Bqm −3 for uranium, 0.29Bqm −3 for thorium, and 2.5Bqm −3 for 210 Pb. More than 150 different waters were analysed for uranium content and only 30 for lead and thorium. The investigations are still in progress.