Gross alpha and beta activity analysis in water--a routine laboratory method using liquid scintillation analysis.

The generally accepted method for gross alpha and beta activity analysis of drinking water in Australia is based on ISO methods; ISO9696, water quality--measurement of gross alpha activity in non-saline water--thick source method, and ISO9697, water quality--measurement of gross beta activity in non-saline water. A liquid scintillation (LSA) based method that requires smaller sample quantities, less sample preparation time and operator intervention, and produces adequate minimum detection levels for local drinking water guidelines has been developed. A synthetic groundwater sample was analysed using the LSA method and compared with results from ISO method techniques used by two independent Australian laboratories. The results show that the LSA method exceeds performance of the ISO methods in measurement accuracy.