Yusof, AMTing, SWWang, LKAkyil, S2019-10-272019-10-2720010236-57310236-5731https://hdl.handle.net/11454/357505th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC-V) -- APR 09-14, 2000 -- KAILUA-KONA, HAWAIIThe determination of Sr-90 and the gross cc-particle activity originating from radium isotopes was performed on water samples at various stages of treatment taken from water treatment plants before distribution to the consumers. Four stages of analyses were involved in the radiostrontium determination, namely scavenging-precipitation as a pre-purification step, separation of 90Sr and Ca from the matrix constituents, separation of Sr-90 from calcium and finally the purification of Sr-90. Both the detection and chemical efficiencies were performed using standard Ra-226 solution in the gross alpha -particle activity determination. The Sr-90 and gross a-particle activities were measured using a Canberra Alpha/Beta System Model 2400 low alpha/beta counter. The average activity reported for Sr-90 for the drinking water samples was 0.52 0.07 Bq/l, which is lower than the maximum permissable level (MCL) of 1.11 Bq/l allowed by WHO. The average reading recorded from 12 water samples from different treatment plants for gross a-particle activity was 0.396 +/- 0.039 Bq/l and this is much lower than the maximum contaminant level (MCL) suggested by the USEPA which is 0.555 Bq/l. However the specific activity for Ra-226 for clean water was 0.268 +/- 0.035 Bq/l, higher than the MCL of 0.185 Bq/l. Generally the treatment process has effectively reduced the natural radioactivity concentrations in all water samples taken at various stages of the process. The results obtained from this study were also discussed in the context of the source of raw water and its environment.eninfo:eu-repo/semantics/closedAccessArticle2491233238WOS:000170616400038Q2Q3