Spatial distribution of soil contamination by 137Cs and 239,240Pu in the village of Dolon near the Semipalatinsk nuclear test site: new information on traces of the radioactive plume from the 29 August 1949 nuclear test.

The village of Dolon located about 60 km northeast from the border of the Semipalatinsk Nuclear Test Site in Kazakhstan is one of the most affected inhabited settlements as a result of nuclear tests by the former USSR. Radioactive contamination in Dolon was mainly caused by the first USSR nuclear test on 29 August 1949. As part of the efforts to reconstruct the radiation dose in Dolon, Cs and Pu in soil samples collected from 26 locations in the vicinity of and within the village were measured to determine the width and position of the center-axis of the radioactive plume that passed over the village from the 29 August 1949 nuclear test. Measured soil inventories of Cs and Pu were plotted as a function of the distance from the supposed center-axis of the plume. A clear shape similar to a Gaussian function was observed in their spatial distributions with each maximum around a center-axis. It was suggested that the plume width that contaminated Dolon was at most 10 km and the real center-axis of the radioactive plume passed 0.7-0.9 km north of the supposed centerline. A peak-like shape with the maximum near the center-axis was also observed in the spatial distribution of the Pu/Cs activity ratio, which may reflect the fractionation effect between Pu and Cs during the deposition process. These results support the recently reported results. The data obtained here will provide useful information on the efforts to estimate radiation dose in Dolon as reliably as possible. Health Phys. 94(4):328-337; 2008.     

Determination of radiostrontium isotopes: A review of analytical methodology

A great number of analytical methods have been developed and applied for the determination of ⁹⁰Sr and ⁸⁹Sr in environmental and nuclear samples using various measuring techniques, i.e. beta counting, liquid scintillation spectrometry and mass spectrometry. This paper is intended to give an overview about the development of the radiochemical procedures for the separation of strontium and/or yttrium including the classical procedure based on a series of semi-selective precipitations, the ion exchange and solvent extraction procedures and the recently developed extraction chromatographic ones offering high selectivity. An outlook to the procedures under development aiming the technological separation of strontium from radioactive wastes and process solutions is also given. Nuclear measuring techniques and mass spectrometric techniques will be comparatively evaluated.     

Ogoya underground laboratory for the measurement of extremely low levels of environmental radioactivity: review of recent projects carried out at OUL.

Recent topical measurements performed in the Ogoya Underground Laboratory are briefly summarized. The paper deals mainly with the following topics: measurements of variations of airborne 222Rn, 210Pb, 210Po and 7Be with high temporal resolution; the depth profile of 137Cs in Pacific water collected in 1957; cosmic-ray-induced 22Na in surface air, rain, river and lake waters; 152Eu in granite exposed to the Atomic Bomb in Hiroshima in 1945; and depleted uranium used in the Iraq War 2003.     

Validation of rapid methods for the determination of radiostrontium in milk

A rapid method of ⁸⁹Sr and ⁹⁰Sr comprising ion chromatography for preconcentration and Sr extraction chromatography for separation of Sr from Ca, Ba and Y was validated with spiked milk samples. An ⁸⁹Sr/⁹⁰Sr activity ratio of up to 12 showed the relative bias was within ±20%. The separation time of Sr was 7 h and the chemical recovery of Sr ranged from 80% to 95%. The detection limit for 500 mL milk and 90 min counting time was 0.1 Bq L⁻¹.     

Atomic bomb induced 152Eu: reconciliation of discrepancy between measurements and calculation

In order to resolve the discrepancy between the measured and calculated 152Eu activity induced by the atomic bomb at Hiroshima, extremely low background gamma-ray spectrometry was performed for 17 granite samples collected from 134 m to more than 3 km from the hypocenter. Measurements agreed well with theoretical calculations based on DS02 up to 1.4 km from hypocenter.     

Developmental toxicity of cesium in the mouse

• 1.1. Maternal intake of 1 mEq CsCl in drinking water at conception until weaning the offspring mice resulted in certain maternal mediated neonatal and developmental toxicity.
• 2.2. Initial reduction in body and brain weights were determined in male offspring due to maternal exposure to Cs salt before they attained the control levels.
• 3.3. Offspring from both sexes showed increased spleen weight from control as a consequence of maternal exposure to Cs. This may precipitate delayed immunotoxicity.
• 4.4. Maternal Cs exposure did not alter litter size or specific activities of offspring heart lactate dehydrogenase isoenzymes from respective controls.
• 5.5. Maternal exposure to Cs altered specific activities of offspring liver alcohol- and aldehyde dehydrogenase during development compared to controls.
• 6.6. The results indicate neonatal and developmental toxicity of Cs as a function of maternal intake of CsCl during pregnancy and breast feeding.

     

Variation of uranium isotopic composition in soil within the JCO grounds from the 30 September 1999 criticality accident at JCO,Tokai-mura,Japan

Following the 30 September 1999 criticality accident at JCO, 29 surface and 3 core soil samples were collected inside and outside the JCO grounds to evaluate possible contamination by 235U-enriched uranium (18.8%) being handled at the time of the accident. Uranium (234U, 235U, and 238U) and thorium (228Th, 230Th, and 232Th) isotopes were determined by alpha-spectrometry and ICP-MS after radiochemical separation. Concentrations of 238U and 234U ranged from 11.3 to 63.5 and 11.6 to 360 mBq g(-1), respectively. Higher amounts of 238U and/or 234U were found in the vicinity of the uranium conversion building. The calculated 234U/235U activity ratios ranged from a 1.0 radioactive equilibrium value to an unusually high 5.7 value. Several of the soil samples showed considerably higher 235U/238U atomic ratios (1.06-4.37%) than 0.725% for natural uranium. Based on the assumption that measured U-series nuclides in soil samples taken from the JCO grounds were almost at radioactive equilibrium up to 230Th, excess uranium could be calculated for each sample. The results suggest that the excess uranium in the soils have lower 235U/238U atomic ratios (a few %) than the 18.8% enrichment of the precipitation tank uranium.     

Determination of 240Pu/239Pu isotopic ratios in human tissues collected from areas around the Semipalatinsk Nuclear Test Site by sector-field high resolution ICP-MS

Information on the 240Pu/239Pu isotope ratios in human tissues for people living around the Semipalatinsk Nuclear Test Site (SNTS) was deduced from 9 sets of soft tissues and bones, and 23 other bone samples obtained by autopsy. Plutonium was radiochemically separated and purified, and plutonium isotopes (239Pu and 240Pu) were determined by sector-field high resolution inductively coupled plasma-mass spectrometry. For most of the tissue samples from the former nine subjects, low 240Pu/239Pu isotope ratios were determined: bone, 0.125 +/- 0.018 (0.113-0.145, n = 4); lungs, 0.063 +/- 0.010 (0.051-0.078, n = 5); and liver, 0.148 +/- 0.026 (0.104-0.189, n = 9). Only 239Pu was detected in the kidney samples; the amount of 240Pu was too small to be measured, probably due to the small size of samples analyzed. The mean 240Pu/239Pu isotope ratio for bone samples from the latter 23 subjects was 0.152 +/- 0.034, ranging from 0.088 to 0.207. A significant difference (a two-tailed Student's t test; 95% significant level, alpha = 0.05) between mean 240Pu/239Pu isotope ratios for the tissue samples and for the global fallout value (0.178 +/- 0.014) indicated that weapons-grade plutonium from the atomic bombs has been incorporated into the human tissues, especially lungs, in the residents living around the SNTS. The present 239,240Pu concentrations in bone, lung, and liver samples were, however, not much different from ranges found for human tissues from other countries that were due solely to global fallout during the 1970's-1980's.     

Epstein–Barr virus-associated leukemic lymphoma after allogeneic stem cell transplantation

Leukemic Epstein–Barr virus (EBV)-associated post-transplant lymphoproliferative diseases (PTLD) following allogeneic hematopoietic stem cell transplantation are extremely rare. We can successfully treat an EBV-associated leukemic lymphoma patient with rituximab, cidofovir, and donor lymphocyte infusion (DLI). In the present case, EBV-specific T cells that were present in the peripheral blood before rituximab administration treatment rapidly increased after DLI in association with a decrease in the EBV-DNA load.     

人体内铅-210和钋-210的浓度

使用低本底α谱仪和²⁰⁹Po放射性示踪剂测定了22例日本人体内胸骨、肝、肾、肺、脾、胆囊、胰腺、性腺和肌肉中²¹⁰Po、²¹⁰Pb的浓度。9种脏器或组织中,胸骨、肝和肾中浓度较高,²¹⁰Po浓度分别为1.29、1.69、1.22Bq·kg^-1湿重;²¹⁰Pb浓度分别为1.27、0.56、0.43Bq·kg^-1湿重。除肝和肾中放射性浓度比明显大于l外,其他组织比值的均值在0.8～1.2之间。根据IcRP参考人数据估算全身负荷量,²¹⁰Po为19.1Bq,²¹⁰Pb为15.8Bq。