Gross Alpha and Gross Beta Activities of Tap Water Samples from Different Locations of Dhaka City

Abstract

Gross alpha and gross beta activities were determined for twenty tap water samples collected from different locations in Dhaka city. The instrumentations used to count the gross alpha and gross beta activities were ZnS scintillation detector and gas proportional counter, respectively. Concentrations ranging from 1.88 ± 0.03 mBq / l to 8.16 ± 0.03 mBq / l with an average 3.76 ± 1.50 mBq / l and from 29.305 ± 0.06 mBq/ l to 115.74 ± 0.16 mBq / l with an average 60.41 ± 23.57 mBq /l were observed for the gross alpha and gross beta activities, respectively. The results showed that the natural activities of alpha and beta emitting radionuclides in tap water samples did not exceed WHO recommended levels and were comparable with the data available in other parts of the world. It suggests that the radioactivity in tap water for the people residing in Dhaka city is not yet a problem. To ensure the safe level of radioactivity in drinking water, however, periodic monitoring of water quality for compliance is necessary. DOI: http://dx.doi.org/10.4038/sljp.v13i1.3917 Keywords: Gross Alpha; Gross beta; Tap water; ZnS Scintillation Counter and Gas Proportional Counter Sri Lankan Journal of Physics, Vol. 13(1) (2012) 01-08