W artykule przedstawiono historię oraz stan obecny rozwoju radiochemii, radioekologii oraz analizy radiochemicznej na Pomorzu Gdańskim. Szczególną uwagę poświecono badaniom naukowym realizowanym na Wydziale Chemii Uniwersytetu Gdańskiego.
Jamske Pleso lake is one of almost 200 lakes located in the Tatra Mountains. This post glacial water reservoir is set on a strictly protected area. In this work, sediment samples taken from Jamske Pleso Lake were analysed for radioactivity of natural 226Ra, 210Po, 210Pb and artificial 137Cs. The sediment core was taken by use of Limnos corer. After preparation of the physical sample, gamma measurements were executed in hermetically closed vessels. A preliminary study showed that concentration of natural radionuclides is in typical values for lakes located in this area. An elevated concentration of 226Ra (mean 57 ± 29 Bq ∙ kg–1) is an effect of uranium rich bedrock of the lake. Radioactivity of 137Cs is close to that reported in other Tatras lakes. Using 137Cs as an indicator allowed a preliminary estimate of the depth of the sediments deposited in 1960s.
PL
Jamski Staw (słow. Jamské Pleso) to jeden spośród niemal 200 tatrzańskich stawów. Ten zbiornik o charakterze polodowcowym położony jest na terenie objętym ochroną ścisłą. Celem niniejszej pracy było wyznaczenie poziomu radioaktywności naturalnych 226Ra, 210Po i 210Pb oraz sztucznego 137Cs w profilach osadów dennych pobranych z Jamskiego Stawu. Profile rdzeniowe osadów pobrano przy pomocy czerpaka firmy Limnos. Po wstępnej obróbce próbek i umieszczeniu ich w szczelnych naczyniach pomiarowych poddano je analizie z wykorzystaniem spektrometru promieniowania gamma. Wstępne wyniki pokazały, że radioaktywność naturalnych izotopów jest na zbliżonym poziomie, do notowanej w innych stawach tego regionu. Podniesiony poziom radioaktywności 226Ra (średnia 57 ± 29 Bq ∙ kg–1) jest związany z zawierającym uran, granitowym trzonem podłożem skalnym jeziora. Radioaktywność 137Cs jest na podobnym poziomie co w innych stawach tatrzańskich. Wykorzystanie 137Cs jako znacznika czasu pozwoliło na wstępną identyfikację warstw osadów nagromadzonych w latach 60. XX wieku.
Chemistry - radiochemistry, radiation chemistry and nuclear chemical engineering play a very important role in the nuclear power development. Even at present, the offered technology is well developed, but still several improvements are needed and proposed. These developments concern all stages of the technology; front end, reactor operation (coolant chemistry and installation components decontamination, noble gas release control), back end of fuel cycle, etc. Chemistry for a partitioning and a transmutation is a new challenge for the chemists and chemical engineers. The IVth generation of nuclear reactors cannot be developed without chemical solutions for fuel fabrication, radiation-coolants interaction phenomena understanding and spent fuel/waste treatment technologies elaboration. Radiochemical analytical methods are fundamental for radioecological monitoring of radioisotopes of natural and anthropological origin. This paper addresses just a few subjects and is not a detailed overview of the field, however it illustrates a role of chemistry for a safe and economical nuclear power development.
This work presents the distribution of radioactive caesium in several types of forest soil originating from the Lesisko reserve (Opole Province, Poland). Vertical distribution of 137Cs isotope was determined in the profiles related to physicochemical properties of different types of soils and their location. Thickness of emerging genetic horizons, structure and morphology of soil profiles were determined. The highest 137Cs activities were found in Of and A horizons. At the same time, there was a sudden drop of 137Cs activity in mineral horizons of soil profiles. By analysis of caesium radioisotope content and its distribution in soil profiles significant correlations were observed between certain physicochemical properties (e.g. pH value, hydrolytic acidity, granulometric composition) of soils in selected forest habitats.
Effects are described of internal exposure doses of ionizing radiation in above- and underground parts of test plants under natural conditions and in roots of Lepidium sativum L. from accumulated 137Cs under laboratory conditions. In the region most contaminated after the Chernobyl accident, in the tested 10 plant species for 137Cs ionizing radiation the internal exposure doses 3.5 times exceeded those in the Ignalina Nuclear Power Plant environment. Under laboratory conditions the effect of low internal (0.6-600 mSv) and external (40-5500 mSv) exposure doses from 137Cs on garden cress, Lepidium sativum L. roots was, practically, the same. Both internal and external exposure doses stimulated the plant root growth by 12 and 33%, respectively. Different effect of external and internal exposure on the developing plant cells was observed by analyzing the results of morphometric investigations of the primary root cap cells of Lepidium sativum L.
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The accident at the of nuclear power plant at Chernobyl resulted in surface contamination of soils across large areas of Europe, including Poland. Mappings aimed of defining the scale of contamination were done in Poland in 1993, using gamma spectrometry. Maps of uranium, thorium, potassium, post-Chernobyl caesium (a sum of radioisotopes 134Cs + 137Cs) content and of gamma dose rate have been published in scale 1 : 750,000 basing on data from over 20,000 measurement points, located regularly each 1000 m along traverse lines (40 traverses) oriented N-S and spaced each 15"longitude in the whole country. In Poland several areas with increased concentration of caesium isotopes were identified. The largest one is so the called Opole anomaly located in the south-western Poland. In 1994 in the area of Opole anomaly were realised the precise mappings in 1 : 100,000 scale. During these studies the first geochemical soil profiles of caesium distribution and of caesium bioaccumulation in grasses were obtained. The results shown that in 1994, 8 years after the fall-out of radioactive caesium, 80-90% of it resides in the top, 10 cm thick, layer of soil in turn leading to a higher caesium content in grasses. In 1996-1997 the spectrometric analyses and studies of distribution of natural and artificial radioisotopes in soil profiles were repeated in the Opole region. They included also concentration analyses of post-Chernobyl caesium within plants and duffs. In 189 soil samples the concentrations of caesium radioisotopes: (137Cs and 134Cs) and of natural radionuclides were determined. Results of radioecological analysis indicate a lack of caesium radioisotope concentrations higher than doses accepted for edible crops. Thus, the studied regions, although the most contaminated in the whole Poland area, are not areas of radiological hazard.
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