Application of in-house method for determinationof radium isotopes in environmental samples usingthe Liquid Scintillation counting technique

Abstract

A method for determination of 226 Ra and 228 Ra in environmental samples using the α-β coincidence liquid scintillation counting (LSC) has been developed. Radium were preconcentrated from environmental samples by coprecipitation with BaSO 4 , then purified from others radionuclide interferences using the cation column exchange (Bio-Rad AG 50 W-X4 resin with 200 -400 mesh size and H + form) and operating in warm temperature which is between 70˚C -80˚C. Then, the Ba(Ra)SO 4 precipitate was filtered through the Millipore filter paper, dried and weighed to calculate chemical yield. The activity concentration of radium isotopes in mixture of liquid scintillation cocktails were measured using LSC after being stored for over 21 days to allow the growth of the progeny nuclides. The method has been validated with a certified reference material supplied by the International Atomic Energy Agency and reliable results were obtained. The radiochemical yields for radium were 59% -90% and recovery was 97% and 80% for 226 Ra and 228 Ra, respectively. Sixteen seawater and fish flesh samples collected in Kapar coastal water have been analyzed with the developed method. The obtained radium activity concentrations in seawater were in the range of 2.08 ± 0.82 mBq/L to 3.69 ± 1.29 mBq/L for 226 Ra and 6.01 ± 3.05 mBq/L to 17.07 ± 6.62 mBq/L for 228 Ra. Meanwhile, the activity concentrations of 226 Ra and 228 Ra in fish flesh were in the range of 11.82 ± 5. Bq/kg dry wt., respectively.

Assessment of Radiation and Heavy Metals Risk due to the Dietary Intake of Marine Fishes (Rastrelliger kanagurta) from the Straits of Malacca

“…In all of these cases, the results are very much lower than that of present observations. Conversely, Ariffin et al 2011 [ 48 ] have reported average activity ranges for 226 Ra and 228 Ra in the soft tissue of fish collected from Kapar, Klang, Malaysia (near to Port Klang and very near to the 2420 MW Kapar coal-fired power plant) of 11.82 ± 5.23 to 16.53 ± 6.53 Bq kg −1 and 43.52 ± 16.34 to 53.57 ± 19.86 Bq kg −1 respectively, being considerably greater than the present study.…”