Measurement of radioactivity in spa waters using gamma spectrometry and evaluation of health risks

Abstract

Exposure of human beings to radiation from natural sources is a permanent and unavoidable part of life on earth, in this study; we are interested in measuring the concentrations of naturally occurring radionuclides in spa water, such as 40K, 232Th, 235U, 226Ra and 238U, using gamma spectrometry with a hyper pure germanium (HPGe) detector. We analysed four samples from different regions of Algeria. The samples were imbedded in 1L vials and stored for at least 21 days to achieve secular equilibrium between 226Ra and its short-lived daughter products before analysing by gamma ray spectrometry. To assess the radiological effects of these four samples, we calculated the annual effective dose AED. The doses received by the public are calculated based on the values of specific activities of 226Ra, 232Th, 238U, 40K and 235U. The average activity concentrations for the samples were 7.4± 0.7 to 10.78± 0.70 Bq/L for 238U; 1.53± 0.09 to 3.5± 0.15 for 226Ra; 0.08± 0.01 to 1.4± 0.08 for 232Th; 2.30± 0.12 to 5.51± 0.2 for 235U and 8.06± 0.4 to 40.30± 2.11 for 40k.The estimated doses for 226Ra exceed the WHO and UNSCEAR recommended values of 0.26 mSv/y and 0.29 mSv/y respectively in all samples. The total annual effective doses for sample S02 exceed the ICRP recommended limit 1 mSv/y.