Elements of Natural Radioactive Decay Series In Iranian Mineral Water and Cigarettes

The Uranium (U) decay series provides the most important isotopes of elements Radium (Ra), Radon (Rn) and Polonium (Po) with half-lives of 1600 years, 3.8 days and 140 days, respectively. Although the chemical structure of radium is very similar to calcium, the fact that it produces a radioactive gas (Radon) complicates its handling in the laboratory and natural environment. The average concentrations of naturally occurring radio nuclide Ra in drinking water at different parts of Iran were used to estimate the annual effective dose equivalent. In another research, concentrations of Po in Iranian cigarettes were measured for the internal intake of this radionuclide and its concentration in the lung tissues. The results indicate that the average concentration of Ra in drinking water is low compared to 100 mBq/l that is recommended by the World Health Organization while the average concentration of Po and Pb in Iranian cigarette is relatively high in comparison with other cigarettes found in the market.