Identification and Quantification of Radionuclides in Contaminated Drinking Waters and Pipeline Deposits

There is broad international interest, particularly with Homeland Security and first-responder organizations, in developing a range of effective, robust, and rapid analytical tools to identify terrorist assaults. Accidental or intentional radionuclide contamination of drinking water supplies would have significant public health, social, political, and financial implications even where the real risk might be small given public perception. Rapid identification and assessment of the magnitude of any contamination is critical in managing any threat and ultimately in allaying public and regulator concerns and in steering subsequent remediation operations. Conventional screening techniques do not provide information of the radionuclide present, and subsequent identification techniques are too time-consuming and require some prior knowledge of the nuclide identity to permit accurate quantification. The development described here presents a novel, rapid, and effective radiometric approach using industry-standard liquid scintillation counting equipment that can both identify and quantify alpha and beta radionuclide contamination within 1 h of sample receipt. The liquid scintillation counting (LSC) or liquid scintillation analysis (LSA) method, though widely used by the life science and the ¹⁴C scientific communities since the 1960s, has greater potential than is often used. The technique developed here, which uses multiple quench parameters for nuclide identification, has been tested on both contaminated drinking waters and pipeline scales with compositions typical of those that might be encountered. It is shown to be highly effective both in terms of rapidly identifying the radionuclide and providing a measure of the quantity of radionuclide present. The whole procedure is about to be developed into an integrated analytical system for use by untrained personnel. It is notable that the development could also be readily applied as a QC procedure in routine radioanalytical measurements.