Radionuclide contamination is a serious health issue caused by nuclear experiments and plant accidents, as seen for the Chernobyl and Fukushima nuclear plants. Italy has been especially interested in ...northwestern alpine regions, as have several other nations. The aim of this work was to indagate 134Cs and 137Cs contamination in wild boars, which were considered bioindicators sampled in the Chisone/Germanasca Valley and the Pellice Valley districts (Piedmont, Italy) in two hunting seasons (2014 and 2016). In the 2014 season, only the livers of the animals (n = 48) were sampled, whereas in 2016, five different anatomical sampling sites were sampled for each animal (n = 16). The analyses were conducted in an accredited laboratory (Agenzia Regionale per la Protezione dell'Ambiente-ARPA) by the aid of an HPGe detector (Ortec) with a relative efficiency of 50%. In general, the contamination levels registered in 2014 were under the detection limit for 134Cs and low for 137Cs (Chisone/Germanasca valley: min: 0.0, max: 23.9 median 11.0 Bq/kg vs Pellice valley: min 0, max: 31.7, median: 9.6 Bq/kg) and no health concern can be supposed. In the first-year samples, the liver showed a negative correlation between age and contamination level. In the second year of sampling, low levels were confirmed (min: 3.1 Bq/kg, max: 113.3; median 17.7 Bq/kg). Multiple sampling from the same animal showed that the diaphragm (median = 27.7 Bq/kg) kidney (27.4) and tongue (27.6) were more contaminated than the liver (17.7) and spleen (15.3). Moreover, a linear mixed model revealed a negative organ-by-age interaction, meaning that interorgan differences in contamination level were greater in younger (5-11 months) than in older (18-36 months) animals. Different feeding habits can be the explanation. Our paper shows that muscle sites (diaphragm and tongue) can be useful for radionuclide pollution surveillance in wild boar populations and that younger animals show more interorgan variability in contamination levels than older animals. More investigations are needed to confirm this correlation and to fulfill the request for more data to achieve better risk assessment.
Summary
The occurrence of radiocesium in food has raised sharp health concerns after nuclear accidents. Despite being present at low concentrations in contaminated soils (below μm), cesium (Cs+) can ...be taken up by crops and transported to their edible parts. This plant capacity to take up Cs+ from low concentrations has notably affected the production of rice (Oryza sativa L.) in Japan after the nuclear accident at Fukushima in 2011. Several strategies have been put into practice to reduce Cs+ content in this crop species such as contaminated soil removal or adaptation of agricultural practices, including dedicated fertilizer management, with limited impact or pernicious side‐effects. Conversely, the development of biotechnological approaches aimed at reducing Cs+ accumulation in rice remain challenging. Here, we show that inactivation of the Cs+‐permeable K+ transporter OsHAK1 with the CRISPR‐Cas system dramatically reduced Cs+ uptake by rice plants. Cs+ uptake in rice roots and in transformed yeast cells that expressed OsHAK1 displayed very similar kinetics parameters. In rice, Cs+ uptake is dependent on two functional properties of OsHAK1: (i) a poor capacity of this system to discriminate between Cs+ and K+; and (ii) a high capacity to transport Cs+ from very low external concentrations that is likely to involve an active transport mechanism. In an experiment with a Fukushima soil highly contaminated with 137Cs+, plants lacking OsHAK1 function displayed strikingly reduced levels of 137Cs+ in roots and shoots. These results open stimulating perspectives to smartly produce safe food in regions contaminated by nuclear accidents.
Significance Statement
After nuclear accidents, production of safe food is challenged by the presence of radiocesium in the environment, since crops take up cesium (Cs+) from contaminated soils and transport it to edible parts. Here we report that inactivation with the CRISPR‐Cas system of the main transporter that takes up Cs+ from the soil in rice, OsHAK1, leads to strikingly reduced levels of 137Cs+ in shoots when grown in highly contaminated soil from Fukushima.
Hrvatsko društvo za zaštitu od zračenja (HDZZ) održalo je 13. simpozij s medunarodnim sudjelovanjem u Poreču od 18. do 21. travnja 2023. godine. Suorganizatori simpozija bili su Institut za ...medicinska istraživanja i medicinu rada (IMI), Institut Ruder Bošković (IRB) te Hrvatsko društvo za medicinsku fiziku (HDMF). Branko Petrinec iz Instituta za medicinska istraživanja i medicinu rada. Brojni sponzori i izlagači dali su svoj doprinos simpoziju: glavni sponzor simpozija LKB Vertriebs GmbH, srebrni sponzori Radosys Dosimetric Microscopy i Nuklearna elektrana Krško, te brončani sponzori Dositracker Ltd., Mjerne tehnologije d.o.o., Jasika d.o.o. i Institut za medicinska istraživanja i medicinu rada. Opće teme u znanosti od zračenju, Nuklearne prijetnje - izazovi, Dozimetrija zračenja, Biološki učinci zračenja, Izloženost stanovništva zračenju, Zaštita od zračenja u medicini, Radioekologija, Radon, Neionizirajuća zračenja te Instrumentacija i mjerne tehnike. Ured za ISSN Nacionalne i sveučilišne knjižnice dodijelit će zborniku ISSN broj, što predstavlja priznanje HDZZ-u za redovno publiciranje ovakvog izdanja, a ujedno i obvezu za nastavak izdavačke djelatnosti Društva. Na izboru za nabolje izlaganje prvu je nagradu osvojio Luka Pasariček izlaganjem naziva „Utjecaj parametra „idelt" u programskom paketu phits i metode računanja na iznos linearnog prijenosa energije primarnih protona u radioterapiji" (IRB). Drugo mjesto dodijeljeno je Mihaeli Mlinarić za izlaganje „Kontrola kvaliteta terapijskih distribucija doze u robotiziranoj radiokirurgiji korištenjem dvodimenzionalnog diodnog detektora", dok je treće mjesto pripalo izlaganju Nikole Šegedina „Odredivanje korekcijskih faktora na volumno usrednjavanje za ionizacijske komore različitog volumena u uskim snopovima 60Co". Na izboru najboljeg postera prvu nagradu osvojio je poster „Koncentracija aktivnosti 137Cs u suhim i zamrznutim vrganjima" prve autorice Nore Miljanić (IMI), dok je drugu nagradu osvojio poster „Odredivanje radionuklida u površinskim i vodama za piće te atmosferskim precipitatima na širem području općine Dvor" Petre Tagliaretti (IMI). Održana je i redovita sjednica Zbora članova HDZZ-a, na kojoj je izloženo i prihvaćeno izvješće o radu i financijsko izvješće za proteklu godinu te plan rada i financijski plan za 2023. i 2024. godinu. Za vrijeme predsjedništva Márije Ranogajec-Komor, HDZZ je steklo medunarodni ugled u zajednici zaštite od zračenja kao rezultat znanstvene aktivnosti, uspješne organizacije i suorganizacije regionalnih kongresa IRPA-e i suradnje s drugim društvima za zaštitu od zračenja u Europi. Postignuta je financijska stabilnost Društva koja je omogućila mnogobrojne aktivnosti, izmedu ostalog i provedbu programa za potporu pri sudjelovanju mladih znanstvenika na kongresima IRPA-e. Rad Márije Ranogajec-Komor medunarodno je prepoznat te je 2006. godine primila nagradu „Počasna igla" Austrijskog društva za zaštitu od zračenja za dugogodišnji doprinos medunarodnoj zajednici za zaštitu od zračenja. Madarska akademija znanosti za unapredenje znanstvenog i umjetničkog životu Madara u Hrvatskoj te značajni doprinos suradnji izmedu hrvatskih i madarskih znanstvenika-istraživača 2009. dodijelila joj je medalju „Arany János".
Pacific Northwest National Laboratory has been tasked with demonstrating the unit operations for the Low Activity Waste Pretreatment System with actual Hanford tank waste. Crystalline silicotitanate ...(CST) ion exchange media is planned to be used to remove cesium (
137
Cs) from the aqueous phases of the tank wastes. Washington River Protection Solutions requested that Hanford tank waste collected from tank 241-AP-107 be processed using conceived pretreatment steps (suspended solids removal by filtration, Cs removal by ion exchange), then vitrified. Removal of Cs from these wastes is an important processing step in preparing the waste for long-term safe storage. Batch contact testing was performed to find the Cs load capacity at the equilibrium feed condition. Bench-scale ion exchange testing with approximately 9 L of filtered AP-107 supernate was conducted using CST. Column testing was performed using prototypic LAWPS operations in a lead-lag column arrangement using 10-mL CST beds. Feed was processed until the lag column effluent reached the Hanford Tank Waste Treatment and Immobilization Plant waste acceptance criteria (WAC) for receiving supernatant waste for vitrification (a function of the Na and 137Cs concentrations), at which point, a new lag column was needed to continue processing and the original lag column was moved to the lead position. Greater than 99% of the Cs processed through the ion exchange system was collected on the CST in the columns. The AP-107 feed and column processing effluent underwent extensive characterization to better define waste characteristics and assess fractionation to the CST. Selected batch contact and lead column samples were analyzed to assess particular metal analyte load characteristics. Results of these analyses will be discussed.
Radionuclide contamination in terrestrial ecosystems has reached a dangerous level. The major artificial radionuclide present in the environment is cesium-137 (137-Cs). In humans, animals, and plants ...cesium ion (Cs+) behaves like potassium ion (K+) and it is localized mainly inside the cells. Pancreas and salivary glands secrete Cs in the intestine thus eliminating about 14% of ingested Cs with the feces, the remaining 86% is eliminated by the kidney with the urine. Ingested radiocesium can also cause in humans several cases of pancreatitis with secondary diabetes (type 3c), which are both on the rise in the world. The Author studied the correlation between the geographical map of mortality from pancreatic cancer (PC) and the map of nuclear plant accidents, atomic bomb testing, and radioactive fallout. The worldwide death rate of PC is increasing, but the exact cause is still not known. Published data in medical literature at World, European and Italian levels are reviewed and compared. 137-Cs, with a half-life of about 30 years, is still present in the environment for about 300-600 years. Autoradiographic studies in mice have shown that 137-Cs is concentrated in greater quantity in the pancreas, particularly in exocrine cells, where most malignant PCs originate. Some methods of radiocesium removal and PC prevention are also suggested. But there is still a persistent, and not entirely disinterested, the controversy between damage from high and low exposure to ionizing radiations.
The risks of radioactive waste water release Smith, Jim; Marks, Nigel; Irwin, Tony
Science (American Association for the Advancement of Science),
10/2023, Letnik:
382, Številka:
6666
Journal Article
Recenzirano
In 2011, the east coast of Japan suffered an earthquake and tsunami that resulted in the meltdown of three of the reactors at the Fukushima Daiichi nuclear plant. This led to an uncontrolled release ...of large amounts of radioactive material to the surrounding land and to the Pacific Ocean. More than 10 years later, new releases of radioactive wastewater to the Pacific Ocean from the Fukushima plant have started. The historical ocean contamination from Fukushima included large quantities of long-lived radioactive cesium-137 (137Cs), so there is widespread concern over these new wastewater discharges. However, these releases will result in much lower total radiation doses to people and aquatic ecosystems than the contamination caused by the accident (1–3). Furthermore, aquatic ecosystems, including those around the Chernobyl disaster site, have been shown to be remarkably resilient to radiation (4–7). Thus, the new Fukushima releases are not expected to cause substantial effects on seafood consumers or the marine ecosystem.
Understanding the release and sequestration of specific radioactive signatures into the environment is of extreme importance for long-term nuclear waste storage and reactor accident mitigation. ...Recent accidents at the Fukushima and Chernobyl nuclear reactors released radioactive 137Cs and 134Cs into the environment, the former of which is still live today. We have studied the migration of fission products in the Oklo natural nuclear reactor using an isotope imaging capability, the NAval Ultra-Trace Isotope Laboratory’s Universal Spectrometer (NAUTILUS) at the US Naval Research Laboratory. In Oklo reactor zone (RZ) 13, we have identified the most depleted natural U of any known material with a 235U/238U ratio of 0.3655 ± 0.0007% (2σ). This sample contains the most extreme natural burnup in 149Sm, 151Eu, 155Gd, and 157Gd, which demonstrates that it was sourced from the most active Oklo reactor region. We have discovered that fissionogenic Cs and Ba were captured by Ru metal/sulfide aggregates shortly following reactor shutdown. Isochrons from the Ru aggregates place their closure time at 4.98 ± 0.56 y after the end of criticality. Most fissionogenic 135Ba and 137Ba in the Ru migrated and was incorporated as Cs over this period. Excesses in 134Ba in the Ru point to the burnup of 133Cs. Cesium and Ba were retained in the Ru despite local volcanic activity since the reactor shutdown and the high level of activity during reactor operation.
The presence of anthropogenic radioisotopes in the environment may be due to inappropriate discards, nuclear tests and accidents, which requires and justifies constant monitoring to ensure the safety ...of nuclear applications. The radiometric analysis is a necessary condition for exporting sugar for world consumption. The investigation of
134
Cs and
137
Cs in a sugar matrix is required to predict radiometric anomalies. This work aimed to standardise a semi-empirical radiometric model to characterise and quantify caesium isotopes in sugar. The research was carried out with high-resolution gamma spectrometry, a non-destructive method. The results were applied to the analysis of different types of sugar for export. The models allowed us to determine with excellent resolution the minimum quantifiable activities of 0.74 Bq kg
−1
and 0.48 Bq kg
−1
for
134
Cs and
137
Cs, respectively, which are lower than 600 Bq kg
−1
, reference values adopted by the EU for isotopes in food.
Two cylindrical compacts containing tristructural isotropic (TRISO)-coated particles with kernels that contained a mixture of uranium carbide and uranium oxide (UCO) and two compacts with UO2-kernel ...TRISO particles have undergone 1600°C safety testing. These compacts were irradiated in the US Advanced Gas Reactor Fuel Development and Qualification Program's second irradiation test (AGR-2). The time-dependent releases of several radioisotopes (110mAg, 134Cs, 137Cs, 154Eu, 155Eu, 90Sr, and 85Kr) were monitored while heating the fuel specimens to 1600°C in flowing helium for 300h. The UCO compacts behaved similarly to previously reported 1600°C-safety-tested UCO compacts from the AGR-1 irradiation. No failed TRISO or failed SiC were detected (based on krypton and cesium release), and cesium release through intact SiC was very low. Release behavior of silver, europium, and strontium appeared to be dominated by inventory originally released through intact coating layers during irradiation but retained in the compact matrix until it was released during safety testing. Both UO2 compacts exhibited cesium release from multiple particles whose SiC failed during the safety test. Europium and strontium release from these two UO2 compacts appeared to be dominated by release from the particles with failed SiC. Silver release was characteristically like the release from the UCO compacts in that an initial release of the majority of silver trapped in the matrix occurred during ramping to 1600°C. However, additional silver release was observed later in the safety testing due to the UO2 TRISO with failed SiC. Failure of the SiC layer in the UO2 fuel appears to have been dominated by CO corrosion, as opposed to the palladium degradation observed in AGR-1 UCO fuel.
Radioactive contamination of fruits in the northern Marshall Islands, resulting from the US nuclear weapons testing program in the 1940s and 1950s, is still a human health concern, in particular ...pertaining to island population resettlement and the economic benefit from farming. Over 200 fruits, primarily coconuts and pandanus, were collected on 11 islands from four atolls in the northern Marshall Islands in 2017. The energy spectra from nuclear gamma decays were measured on a research vessel for each fruit in situ. From these recordings, the level of cesium-137 (137Cs) contamination was determined for individual fruits. Comparisons of the results are made to past studies and international food safety standards. There is a broad distribution of values, ranging from below detectable radiation levels to relatively high levels; safety concerns are largest for Bikini Island. A noticeable fraction of fruits from Bikini have significantly higher levels of 137Cs contamination compared with those from all other measured islands.
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