Ultra Low-Dose Radiation: Stress Responses and Impacts Using Rice as a Grass Model

We report molecular changes in leaves of rice plants (Oryza sativa L. - reference crop plant and grass model) exposed to ultra low-dose ionizing radiation, first using contaminated soil from the exclusion zone around Chernobyl reactor site. Results revealed induction of stress-related marker genes (Northern blot) and secondary metabolites (LC-MS/MS) in irradiated leaf segments over appropriate control. Second, employing the same in vitro model system, we replicated results of the first experiment using in-house fabricated sources of ultra low-dose gamma (γ) rays and selected marker genes by RT-PCR. Results suggest the usefulness of the rice model in studying ultra low-dose radiation response/s

Radiation monitoring using imaging plate technology: A case study of leaves affected by the Chernobyl nuclear power plant and JCO criticality accidents

This paper describes the use of a photostimulable phosphor screen imaging technique to detect radioactive contamination in the leaves of wormwood (Artemisia vulgaris L) and fern (Dryopteris filix-max CL. Schoff) plants affected by the Chernobyl nuclear power plant accident. The imaging plate technology is well known for many striking performances in two-dimensional radiation detection. Since imaging plate comprises an integrated detection system, it has been extensively applied to surface contamination distribution studies. In this study, plant samples were collected from high- and low-contaminated areas of Ukraine and Belarus, which were affected due to the Chernobyl accident and exposed to imaging technique. Samples from the highly contaminated areas revealed the highest photo-stimulated luminescence on the imaging plate. Moreover, the radio nuclides detected in the leaves by gamma and beta ray spectroscopy were 137Cs and 90Sr, respectively. Additionally, in order to assess contamination, a comparison was also made with leaves of plants affected during the JCO criticality accident in Japan. Based on the results obtained, the importance of imaging plate technology in environmental radiation monitoring has been suggested

Residual neutron-induced radionuclides in a soil sample collected in the vicinity of the criticality accident site in Tokai-mura, Japan: A progress report

金沢大学理学部Residual neutron-induced radionuclides were measured in a soil sample collected in the vicinity of the location where a criticality accident occurred (in Tokai-mura, from 30 September to 1 October, 1999). Concentrations of 24Na,140La,122Sb,59Fe,124Sb,46Sc,65Zn,134Cs and 60Co in the soil sample were determined by γ-ray spectrometry, and neutron activation analysis was carried out for selected target elements in the sample. Tentative estimates of the apparent thermal and epithermal neutron fluences which reached the sample were obtained through combined analyses of 59Fe/58Fe,124Sb/123Sb,46Sc/45Sc,65Zn/64Zn,134Cs/133Cs and 60Co/59Co. (C) 2000 Elsevier Science Ltd

Determination of uranium and its isotopic composition in human hair by microwave digestion and inductively coupled plasma mass spectrometry

The determination of trace elements in hair has been a subject of continual interest from the viewpoint of biomedical and environmental sciences. However, the level of the elements in normal population should be established. Determination of uranium and its isotope ratios is required in environmental monitoring of nuclear contamination in nuclear safeguards, nuclear accidents and nuclear forensic medicines. 238U, 235U and 234 U are naturally occurring alpha-emitting long-lived radionuclides which are taken up daily at low levels with food and drinking water. A microwave-assisted digestion procedure with nitric acid and hydrogen peroxide of the hair has been developed. The uranium concentration in the diluted sample was determined using ICP-MS and limit of detection was 0.01ng/g for a 50 mg of sample. Natural isotopic composition of 235U/238U =0.00725. Therefore, isotope ratio measurements are important because they can provide information on the origin of uranium. The isotope ratios of uranium, 234U/238U and 235U/238U were measured by using a VG Sector 54 thermal ionization mass spectrometer (TIMS) equipped with a WARP Filter. Precision of 235U/238U ratio was achieved by a correction factor of 0.35% amu as a function of intensity with sample loads of 100 ng of U.17th International Mass Spectrometry Conferenc

Distribution of transuranium elements and other trace elements in environmental samples of South Serbia

Anthropogenic processes (mining, milling, industries, and automobiles) including the modern trends in the agriculture contaminated the soil and water affecting the biogeochemical cycling of many elements. This resulted in the degradation of soil-water system causing damage to the environment and the ecosystem. In addition to this, since depleted uranium (DU) could also have been used in the Balkan conflict 1999, there has been a concern about the possible consequences of its use for the people and for the environment of this region. Therefore, management of fresh water resources is utmost important in the 21st century for the sustainable development. In this context, isotope geochemistry is a very useful tracer tool not only to establish the origin of pollutants and their relative contributions from various sources (natural and anthropogenic) but also the effect on the soil-water system. Isotope studies can be carried out using thermal ionization mass spectrometry (TIMS) and inductively coupled plasma mass spectrometry (ICPMS), and results of such studies are very useful and precise in delineating the source(s) of contaminants, tracing the flow-path of ground water and aid us in planning better management of freshwater resources. We have collected a few well water samples, ground water samples and soil samples in south Serbia region. The sample preparation procedures are critical analytical steps and influence the quality of the final results. The representativeness of the samples examined, a digestion procedure which ensures the quantitative conversion of transuranium elements and other trace elements into a suitable complex and elimination of matrix effects are essential while measuring uranium isotopes, especially in the analysis of environmental materials. Special procedures for the purification of reagents and reaction vessels are required in order to reduce the blank below the limits of detection of the most sensitive detection techniques, such as ICP-MS or TIMS. Method. The soil samples were decomposed using microwave digestion with a mixture of HNO3, HF and HClO4. Water samples were open dried with HNO3. Determination of transuranium elements as well as other trace elements were performed using an ICP-MS. Uranium was isolated from soil and water samples by chemical separation procedure based on the use of anion-exchange resin and UTEVA extraction chromatography. The isotope ratios were measured with a magnetic sector, thermal ionization mass spectrometer equipped with a multiple ion collector system for simultaneous detection of the ion currents. The results and distribution of transuranium elements in water and soil samples will be presented in the lecture. TIMS shows the highest precision and accuracy and capable of detecting depleted uranium in soil samples affected due to conflicts.Promotion of New Electrochemical Etching Facility and Its Applications to Natural Radiation Studies in Western Balkan Countrie