Uranium concentration in typical Pakistani diet.

To strengthen the radiation protection infrastructure in Pakistan, the uranium concentration in daily diet was measured and its associated radiation risks were estimated for the adult population. Food samples were collected from major cities and districts of the country by the market basket method, from which daily diets were prepared. These diet samples were analyzed using inductively coupled plasma mass spectrometry (ICP-MS) at the National Institute of Radiological Sciences, Japan, the regional Central Reference Laboratory of the Reference Asian Man Project. The measured values of the uranium content were found to vary from 2.3 ng (g dry)(-1) to 11 ng (g dry)(-1). The geometric mean concentration and geometric standard deviation were 4.5 x//1.7 ng (g dry)(-1). This leads to a daily dietary intake of 2.6 x// 1.7 microg d(-1) or 33 x// 1.7 mBq d(-1), which is approximately 40% higher than the ICRP value. The measured value, i.e. 33 mBq d(-1), contributes 12 Bq y(-1) to annual intake of 238U activity and 0.54 microSv to the committed effective dose to the adult population. This is a very small fraction of the ICRP annual effective dose limit of 1 mSv for the general public. Therefore, it would pose no significant health hazard.