Abstract. In this study, after the pulse shape calibration of a liquid scintillation counting (LSC) spectrometer (Quantulus 1220), the effi ciency was determined depending on sample quenching parameters. Then, gross alpha and beta activities in two spiked water samples obtained from International Atomic Energy Agency (IAEA) were used for the validation of the ASTM D7283-06 method, which is a standard test method for alpha and beta activity in water by LSC. Later, the drinking water samples (35 tap water and 9 bottled water) obtained from different districts of Ankara, Turkey, were measured. The maximum gross alpha activities are measured to be 0.08 Bq/L for tap waters and 0.13 Bq/L for bottled waters, whereas the maximum gross beta activities are found to be 0.18 Bq/L for tap waters and 0.16 Bq/L for bottled waters. These results indicate that these drinking water samples are below the required limits, which are 0.1 Bq/L for alpha emitting radionuclides and 1 Bq/L for beta emitting radionuclides. As a result, gross alpha and beta activities in drinking water of Ankara were determined accurately by this validated LSC method. It is also worth noting that LSC is a rapid and accurate method for the determination of gross alpha and beta activities without requiring a tedious sample preparation.

The radionuclide activities were measured in sea sediment and coastal sand samples taken from the Black Sea to improve the understanding on coastal pollution as sediments and sand act as a sink for inorganic contaminants from various sources. The core sediments were taken from the Black Sea near to Varna city and sand samples were collected from in the Black Sea Coastal of North Anatolia. Their radionuclide contents were measured using a high resolution gamma-ray spectrometry. The activity results are found to be on the average, 65 ± 9 Bq · kg−1 for 210Pb, 13 ± 1 Bq · kg−1 for 137Cs, 36 ± 4 Bq · kg−1 for 226Ra, 25 ± 3 Bq · kg−1 for 232Th, and 403 ± 13 Bq · kg−1 for 40K in slices from the sediment core. The radionuclide activities in sand samples collected from the Black Sea coastal are measured for 7Be (2.4 ± 0.4 to 5.8 ± 0.4 Bq · kg−1) and for 137Cs (2.0 ± 0.1 to 3.7 ± 0.2 Bq · kg−1). In sand samples, other natural occurring radionuclides 226Ra (6.8 ± 1.1 to 12.5 ± 1.3 Bq · kg−1), 232Th (6.5 ± 0.8 to 16.9 ± 1.4 Bq · kg−1) and 40K(139 ± 8 to 376 ± 16 Bq · kg−1) were also observed, as expected. The present results indicate that there is still noticeable radionuclide contamination in sediments and coastal sands due to mainly the Chernobyl nuclear accident and other conventional industrial wastes.

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