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The determination of natural radionuclide concentrations plays an important role for assuring public health and in the estimation of the radiological hazards. This is especially true for high level radiation areas. In this study, 226Ra, 228Ra and 238U concentrations were measured in well waters surrounding eight of the high-level natural radiation areas in northern Vietnam. The 226Ra, 228Ra and 238U activity concentrations vary from −3–2.7 (0.46), −3–0.43 (0.07) and −3–5.32 Bq/L (0.50 of median), respectively. 226Ra and 238U isotopes in most areas are in equilibrium, except for the DT-Thai Nguyen area. The calculated radiological hazard indices are generally higher than WHO (World Health Organization) recommendations. Average annual effective dose and excess lifetime cancer risk values due to drinking well water range from to 130 to 540 μSv/year and 7.4 × 10−6 to 3.1 × 10−5, respectively.

Data, despite being crucial for internal dose assessment, is lacking on the transfer of artificial radionuclides from the environment to the food supply. Expanding the available information on these factors is important for the improvement of dose models for specific scenarios. This paper describes the results of a 70 day field experiment with broiler chickens on the dynamics of excretion of 137Cs and 241Am from the muscle, liver and bone of broilers after a 30 day application of contaminated feed. The radionuclide concentrations in the feed and the thigh muscle, thigh bone and liver of 54 chickens divided between grass meal and soil contaminated feed groups were evaluated by gamma spectrometry for 241Am and 137Cs. The obtained results confirm previous data on the dynamics of the excretion of cesium from organs, which can be described with a fast and a slow exponential curve of excretion. On the 70th day, following the 30-days application, 2-8% of the first-day activity concentrations of 137Cs in organs (muscle, liver, bone) were detected. In the first two days, activity concentration of 241Am decreases twofold in both liver and bone. 35% of the maximum activity concentration of 241Am remained in bone and 15% in liver on the last day of the experiment.

The Acacia auriculiformis is a tree common in tropical Asian countries, capable of growing in many different soil types, so it could be used for biomonitoring for high natural radionuclide areas in tropical and subtropical climates. The transfer factor (TF) of radionuclides from soil to A. auriculiformis in eight uranium and rare earth element (REE) mining areas of North Vietnam was investigated. The activity concentrations 226Ra, 238U, 137Cs, 228Ra, and 40K in both soil and A. auriculiformis showed considerable variation. The TFs of these radionuclides also varied in a wide range. In most of the eight areas, the highest TF was observed for 137Cs and 228Ra. While the TFs for 226Ra and 238U were smallest. In addition, the TFs for radionuclides near REE mines were similar to those observed near uranium mines. The TFs for A. auriculiformis were within the ranges of TF reported for other plants, except for 137Cs.

The study of staple food products is crucial to assure public safety and provides input for predictive dose assessment models. To further this goal, the activity concentrations, transfer factors, and radiological hazards of 226Ra, 232Th, 40K, and 137Cs were studied for ten pairs of selected vegetables and soils in Tien Le near Hanoi in Vietnam. This is the first study in this area for Vietnamese vegetable samples. The ten most popular vegetables in Vietnamese diet were selected, namely choy sum, crown daisy, lettuce, cabbage, Malabar spinach, beans, sweet potato, potato, kohlrabi and carrot. The research results showed that the activity concentrations observed in vegetable crops did not present the previously reported strong correlation to those in soil. The ranges of TFs of 226Ra, 232Th, and 40K were 4 × 10−2 – 6.9 × 10−1, 8 × 10−2 – 9.7 × 10−1; and 1.0 × 100–1.6 × 101, respectively. Values for leafy vegetables and tubers exceed previous world range figures for Th and K. The soil has been evaluated for radiological hazard indices, which predict almost no risk to human health in the study area.

Horses are important food sources in several countries however, data on their radionuclide uptake is less available than for many other farm animals. Information on the transfer of artificial radioisotopes from the environment to the food supply is necessary for internal dose assessment and assuring the safety of the population relying on this food source. This study provides data for a less studied farm animal and, in the case of 241Am and 239+240Pu, relatively poorly studied radionuclides with respect to transfer to animal products. The transfer parameters for 239+240Pu, 241Am, 137Cs and 90Sr to the organs of 1-year old fillies, 10-year old mares and through the placental barrier into foetuses were quantified after 60-days feeding with contaminated soil or diet contaminated by a leachate solution. The transfer of radionuclides from ingested soil to tissues was generally lower, by up to three orders of magnitude, than from a diet contaminated by a leachate solution. The ingestion of soil is a particularly important source of radionuclide intake to grazing animals in the Semipalatinsk Test Site. For 241Am there is a lack of available data, the two singular entries for mutton and beef in the IAEA handbook are higher than all values observed in the current study. The maximum observed transfer factor for 241Am was 72 ± 22*10−5 d kg−1 FW in the liver of the mare fed with leachate contaminated feed. For 239+240Pu the maximum transfer factor was 31.8 ± 8*10−5 d kg−1 FW observed also in the liver of the mare fed with leachate contaminated feed. The filly fed with leachate contaminated feed had the highest transfer parameter value for 137Cs, 35.3*10−3 d kg−1 FW. The highest 90Sr transfer factor was found in the ribs of the filly fed leachate contaminated feed, 720 ± 144 *10−3 d kg−1 FW. The results presented in this paper can be used to improve the current internal dose estimates from the ingestion of horse meat produced in the area, however they are based on a low sample size; future studies need to use a larger number of animals.

Naturally occurring radionuclides are present in the Earth crust; however, their distribution is not homogeneous. When primary or secondary raw materials containing relatively low concentrations of naturally occurring radionuclides are introduced in an industrial process then the radionuclides can become more concentrated in the produced (by-)products. For example, during the production of purified metals, throughout the purification process, also other elements, such as naturally occurring radionuclides, become concentrated in the by-products. In order to assure radiation protection of the population, it is important to map the potential exposure for workers and the general public. There is an extensive literature available regarding the presence of naturally occurring radionuclides in various by-products; however, it can be hard to review and even to interpret for the regulators and members of the industry in order to assure the safe use of by-products for example in construction. To solve this problem data mining and text processing have been applied to the ever-increasing numbers of publications (More than 39,000 filtered publications have been processed up to the Jan. 6, 2017), and the NORM4Building database has been compiled based on the analysis of the collected data. Based on this database using text analysis methods the most NORM prone raw materials and industries have been identified. This chapter gives a concise overview on the parameters to be considered during the selection of NORM by-products as feedstock for the construction industry, specifically for the production of cement, concrete, and ceramics. In the frame of this chapter the technical and radiological properties of the most representative industrial processes (such as coal mining and combustion; iron and steel production; the alumina, the zirconia, and the phosphate industry; etc.) and their by-products are discussed, especially considering the needs of the construction industry and the new European Basic Safety Standards.