Natural Radioactivity in Sachet Drinking Water Produced in Ibadan, Oyo State, Nigeria

Abstract

Natural radioactivity in twenty (20) brands of sachet water produced in Ibadan, Oyo state, Nigeria was analyzed using well-shielded, calibrated NaI(Tl) gamma spectroscopy. The measured activity concentration varies from 0.89 ± 0.24 Bql-1 to 11.65 ± 2.83 Bql-1 for 238U, 0.41 ± 0.05 Bql-1 to 8.78 ± 0.97 Bql-1 for 232Th and 4.29 ± 0.4 Bql-1 to 37.48 ± 2.51 Bql-1 for 40K. The mean annual effective dose calculated for the age groups 0–1 y, 1–2 y, 2–7 y, 7–12y, 12–17 y, and > 17 y are 4.82, 0.64, 0.57, 0.59, 0.65, 0.76mSv respectively. The total annual effective dose from consumption of some of the sachet water exceeded the world average values of 0.12mSv reported by United Nations Scientific Committee on the Effects of Atomic Radiation. The values also exceed the World Health Organization and International Commission on Radiological Protection recommended values of 0.1mSv and 1.0mSv respectively. This showed that there might be radiological risks arising from the consumption of the analyzed sachet water.