Ingestion of radionuclides and heavy metals through drinking water and food intake represents one of the important pathways for long-term health considerations. Milk and milk products are main constituents of the daily diet. Radionuclides and heavy metals can be apprehended in the ecosystem of the East Singhbhum region which is known for its viable grades of uranium, copper and other minerals. For the risk assessment studies, samples of milk were collected from twelve villages around Bagjata mining area and analysed for U(nat), 226Ra, 230Th, 210Po, Fe, Mn, Zn, Pb, Cu and Ni. Analysis of the results of the study reveals that the geometric mean of U(nat), 226Ra, 230Th and 210Po was 0.021, 0.24, 0.23 and 1.08 Bq l(-1), respectively. The ingestion dose was calculated to be 12.34 μSvY(-1) which is reflecting the natural background dose via the route of ingestion, and much below the 1 mSv limit set in the new ICRP recommendations. The excess lifetime cancer risk was estimated to be 1.72×10(-4) which is within the acceptable excess individual lifetime cancer risk value of 1×10(-4). The geometric mean of Fe, Mn, Zn, Cu and Ni was 4.91, 0.29, 4.77, 0.56 and 0.48 mgl(-1), respectively; whereas the daily intake was computed to be 0.44, 0.03, 0.43, 0.05 and 0.04 mg/day, respectively. Pb was not detected in any of the samples. The hazard quotient revealed that the intake of the heavy metals through the ingestion of milk does not pose any apparent threat to the local people as none of the HQ of the heavy metals exceeds the limit of 1.

Exposure due to natural radiation is of particular importance because it accounts for the largest contribution (nearly 85 %) to the total collective dose of the world population. An attempt has been made to present the feasibility of uranium occurrence in drinking water samples from different states of India, by laser-induced fluorimetry. The associated age-dependent radiation dose was estimated by taking the prescribed water intake values of different age groups. The concentration of uranium obtained, i.e. 0.1 +/- 0.01 to 19.6 +/- 1.8 microg l(-1), is well below the drinking water guideline value of 30 microg l(-1). The annual ingestion dose due to uranium in drinking water for various age groups is found to vary from 0.14 to 48 microSv y(-1).

Heavy metal pollution of water resources can be apprehended in East Singhbhum region which is a highly mineralised zone with extensive mining of copper, uranium and other minerals. Ten groundwater samples were collected from each site and the heavy metal analysis was done by atomic absorption spectrophotometer. Analysis of the results of the study reveals that the concentration of iron, manganese, zinc, lead, copper and nickel in groundwater of Bagjata mining area ranged 0.06-5.3 mg l(-1), 0.01-1.3 mg l(-1), 0.02-8.2 mg l(-1), 1.4-28.4 μg l(-1), 0.78-20.0 μg l(-1) and 1.05-20.1 μg l(-1), respectively. In case of Banduhurang mining area, the range was 0.04-2.93 mg l(-1), 0.02-1.1 mg l(-1), 0.01-4.68 mg l(-1), 1.04-33.21 μg l(-1), 1.24-18.7 μg l(-1) and 1.06-14.58 μg l(-1), respectively. The heavy metals were found to be below the drinking water standards (IS:10500 1993) except iron (0.3 mg l(-1)) and manganese (0.1 mg l(-1)). The hazard quotients of the heavy metals for drinking water were below 1 posing no threat due to intake of water to the people for both the areas.

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Ground water ecosystem surrounding the uranium processing facility at Jaduguda, India has been studied for natural uranium distribution. Annual intake of uranium through drinking water for members of public residing around the uranium complex is found to be in the range of 41.8 Bquy^–1 - 44.4 Bquy^–1. The intake and ingestion dose is appreciably low (<2 Sv.y^–1) which is far below the WHO recommended level of 100 uSv.y^–1. The excess life time radiological risk due to uranium natural in drinking water is insignificant and found to be of the order of 10^–6. Even the highest concentration of uranium was found to be 28 ug.l^–1 is away (at 1.5 to 5 km distance) from mining industry and well below the acceptable limit. The ground water in the area around the uranium facility is not affected by the mining activity. The ground water in three zones is safe and reflects the natural distribution of uranium