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1

Comparison of beta (LSC) and gamma (HPGe) spectrometric methods for lead-210 in chronological study

Mikalauskienė R., Mažeika J., Petrošius R., Szwarczewski P.

Geochronometria

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2018

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Vol. 45, no. 1

34--43

EN

The sediments of two lakes located in the Baltic Uplands, the western part of the East European Plain (East Lithuania and North East Poland), were studied. Activity concentration of 210Pb was determined using two nuclear analytical techniques: determination of 210Pb in equilibrium with its beta emitting daughter 210Bi using liquid scintillation counter (LSC), and direct determination of 210Pb (and other radionuclides) by low-background gamma-ray spectrometer with a well type HPGe detector. For the 210Pb determination by LSC the methodology of lead separation based on the anion exchange resin in Cl– form (Eichrom) was used. Several steps of radiochemical procedures and respective parameters were investigated additionally. The optimized procedures for LSC method were used for case study with two lake cores. The activity concentration of 210Pb in lake sediment samples based on both nuclear analytical techniques (LSC and HPGe) were compared. 210Pb dating of cores was performed according to Constant Rate of 210Pb Supply (CRS) model with some modifications. Both techniques in the range of uncertainties gave similar results. From two considered lakes, the more eutrophic one exhibited higher sediment mass accumulation rate (MAR) values.

2

Pb-210 isotope as a pollutant emission indicator

Dołhańczuk-Śródka A., Ziembik Z., Kříž J., Hyšplerova L., Wacławek M.

Ecological Chemistry and Engineering. S

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2015

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Vol. 22, nr 1

73--81

EN

Passive biomonitoring using 210Pb was used in the paper to evaluate pollutant deposition. Well-developed epiphytic foliose lichens Hypogymnia physodes growing on spruce branches were used in the studies. The samples of mosses Pleurozium schreberi and soil (raw humus) were collected from the area around the tree from which the samples of lichens were collected. The studies have shown that it is possible to identify dust emission sources using a radioactive lead isotope (210Pb). The highest activity of 210Pb was observed in areas with increased deposition of other pollutants, such as Ni, Cd, Cu and Pb, which may indicate that 210Pb is one of the emission components.

PL

W pracy zastosowano biomonitoring pasywny, z wykorzystaniem 210Pb, do oceny depozycji zanieczyszczeń. Do badań wykorzystano dobrze wykształcone epifityczne porosty listkowate Hypogymnia physodes, porastające gałęzie świerka. Wokół drzewa, z którego pobrano próbki porostów, pobierano próbki mchów Pleurozium schreberi oraz gleby - próchnicy nadkładowej. W prowadzonych badaniach stwierdzono, że możliwa jest identyfikacja źródeł emisji pyłu przy wykorzystaniu radioaktywnego izotopu ołowiu - 210Pb. Największe aktywności 210Pb zaobserwowano na terenach o zwiększonej depozycji innych zanieczyszczeń, np. Ni, Cd, Cu i Pb, co może wskazywać, że 210Pb jest jednym z komponentów emisji.

3

Sedimentation rates in the Lake Qattinah using 210Pb and 137Cs as geochronometer

Alhajji E., Ismail I. M., Al-Masri M. S., Salman N., Al-Haleem M. A., Doubal A. W.

Geochronometria

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2014

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Vol. 41, no. 1

81--86

EN

The constant rate of supply (CRS) of excess 210Pb model was successfully applied to assess 210Pb data of two sediment cores from the lake Qattinah, Syria. Gamma spectrometry was used to determine 137Cs and 210Pb activity concentrations. The bottom of the cores was 210Pb-dated to years 1907 and 1893. The accumulation rates were determined using 210Pb method and found to vary similarly in both cores from 0.10 ± 0.01 to 3.78 ± 0.57 kg m-2 y-1 during the past century. 137Cs was used as an independent chronometer. The two distinct peaks observed on the 137Cs record of both cores, corre-sponding to 1965 and 1986, have allowed a successful validation of the CRS model.

4

Sediment geochronology and spatio-temporal and vertical distributions of radionuclides in the Upper Bonny Estuary (South Nigeria)

Omokheyeke O., Sikoki F. D., Laissaoui A., Akpuluma D., Onyagbodor P. O., Benkdad A., Benmansour M.

Geochronometria

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2014

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Vol. 41, no. 4

369--376

EN

Surface deposits and sediment cores were collected from the Upper Bonny Estuary, located in Southwest Nigeria, and analyzed to determine spatio-temporal and vertical distributions of radio-nuclide activities expressed in Bq·kg−1 dry weight. The results of activities of naturally occurring radionuclides of 226Ra (15 ± 2–34 ± 3 Bq·kg−1), 228Ra (32 ± 5–48 ± 6 Bq·kg−1), 40K (264 ± 29–462 ± 36 Bq·kg−1) were found to be all within the range of typical values reported for coastal regions. Ratios of 226Ra to 228Ra suggested accretion for all samples with low sediment accumulation registered during rainy months. In addition, vertical distributions at the three sampling sites were also studied with the initial aim of establishing chronologies from the decay of excess 210Pb. In two cores, excess 210Pb, estimated by subtracting 226Ra from total 210Pb on a layer-by-layer basis, exhibit relatively constant activity with discrete minima and maxima. Therefore, these cores were excluded from radiometric dating. Only the third core could be dated by the constant rate of supply model, and 137Cs was utilized to validate the 210Pb chronology.

5

Analysis of naturally occurring radioactive material using neutron activation analysis and passive Compton suppression gamma - ray spectrometry

Landsberger S., George G., Lara R., Tamalis D., Louis-Jean J., Dayman K.

Nukleonika

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2012

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Vol. 57, No. 4

461-465

EN

Naturally occurring radioactive material (NORM) still remains a problem in oil and gas exploration. Radioactive wastes from oil and gas drilling take the form of produced water, drilling mud, sludge, slimes, or evaporation ponds and pits. In many parts of the USA the soil contains radioactivity that is then concentrated in mineral scales on the pipes, storage tanks and other extraction equipment. The radionuclides 226Ra and its one of daughter products 210Pb and 228Ra from 232Th are the primary radionuclides of concern in the waste. We have investigated the concentrations of heavy metals in NORM using neutron activation analysis (NAA) as well as using passive radioactivity counting using Compton suppressed gamma-ray spectrometry. With a low-energy germanium counter and the Compton suppression system low detection limits were achieved to measure 226Ra, 228Ra and 210Pb. Results have shown very elevated amounts for these radionuclides as well as the heavy metals of barium and strontium.

6

Development of lead-210 measurement in peat using polonium extraction. A procedural comparison

De Vleeschouwer F., Sikorski J., Fagel N.

Geochronometria

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2010

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Vol. 36

1-8

EN

Two chemical treatments for lead-210 measurement were compared on the sub-surface samples of a core from an ombrotrophic bog from East Belgium. The classical procedure involves a concentrated acid extraction of polonium. However, this treatment represents substantial health risks together with unknowns regarding both the degree of cleanliness and the Po extraction rate, and most importantly, is rather time consuming. We developed here an improved procedure involving an ashing step prior to acid extraction. This allows substantial improvements such as: 1/ the use of a relatively small amount of acid compared to the classical procedure and 2/ the substantial reduction of a total sample digestion time. Measurements of 210Pb concentrations were conducted by alpha spectrometry. Results show a good agreement of unsupported 210Pb activity obtained for both procedures, although some unknowns remain concerning the adsorption of 210Po on the plastic test tube, the volatilization of a small amount of ash, or the absorption of alpha particle at the alpha source surface. This however should not affect the 210Pb measurement as all the samples are spiked prior to ashing (i.e. the recoveries are fully monitored). Through this study, we are suggesting researchers to follow this new procedure in order to increase safety, cleanliness, better recovery and substantial time gain.

7

Aktywność 210Pb w wybranych wodach podziemnych z obszaru Karpat polskich

Chau N. D., Rajchel L., Duliński M.

Biuletyn Państwowego Instytutu Geologicznego

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2009

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nr 436, z. 9/1

35-40

PL

W pracy przedstawiono rezultaty analiz aktywności ołowiu 210Pb w 31 próbach wód pobranych ze źródeł i odwiertów na obszarze Karpat polskich. Badaniami objęto trzy typy chemiczne wód. W 23 przypadkach były to szczawy, reprezentowane zarówno przez wody przeznaczone do spożycia, jak i wykorzystywane w balneologii do kąpieli leczniczych. Drugim typem (3 próbki) były wody siarczkowe, stosowane głównie do kąpieli leczniczych. Trzeci typ (5 próbek) stanowiły wody chlorkowe o mineralizacji od 3,5 do 8,0 g/l, stosowane w kuracji pitnej, oraz o mineralizacji od 19 do 28 g/l - wykorzystywane do zabiegów kąpielowych. Jakkolwiek w świetle uzyskanych wyników izotop 210Pb (pojedynczo) nie stanowi zagrożenia radiologicznego, niemniej jednak powinien być uwzględniany przy szacowaniu obciążającej dawki skutecznej, wynikającej z zawartości wszystkich izotopów promieniotwórczych obecnych w wodach podziemnych dostępnych dla ogółu ludności. Szczególną uwagę należy zwrócić na zagrożenia, które mogłyby wynikać w sytuacji podawania niektórych z tych wód niemowlętom i małym dzieciom.

EN

Activity of 210Pb measured in some groundwaters of the Polish Carpathians proves that this isotope is not radiologically hazardous. However, it should be incorporated in calculations of the total effective dose resulted from intake of radionuclides present in drinking waters. A special care should be taken in situations when some of these waters are used in diet of babies and young children.

8

Sedimentation rates and dating of bottom sediments in the Southern Baltic Sea region

Suplińska M. M., Pietrzak-Flis Z.

Nukleonika

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2008

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Vol. 53, suppl. 2

105--111

EN

Sedimentation rates and dating of bottom sediments were estimated in two sampling stations of the Gulf of Gdańsk and in four stations in the open sea area. Estimations were based on vertical distributions of 210Pb, 137Cs and 239,240Pu activity concentrations in sediment core samples taken in 1998–2007. Two dating models based on changes of activity concentrations of 210Pbunsup were used: 1) CF:CS (Constant Flux Constant Sedimentation rate-model) and 2) CRS (Constant Rate of Supply-model). 137Cs and 239,240Pu were applied as time markers. 137Cs originates mostly from the Chernobyl accident in 1986, whereas 239,240Pu comes from the global fallout in 1963. The validation of the 210Pb methods was performed by activity peak of 137Cs and 239,240Pu. Sediment accumulation rate (g·cm–2·y–1) was constant along sediment core. Annually accumulated layer, (mm·y–1) decreased with sediment depth in all the locations. In the Gulf of Gdańsk sedimentation rate in the upper layer was about 3.6 mm·y–1, and it decreased in the deeper layers to about 1.1 mm·y–1. Sedimentation rates in the open sea area were lower than in the gulf region and the lowest was observed in the Bornholm Deep, being about 0.95 mm·y–1 in the upper layer and 0.35 mm·y–1 in the deeper layer. The growth of a 5 cm thick layer took 27–37 years in the Gulf of Gdańsk, and 61–105 years in the open sea area. It is suggested that the mean values obtained from the models would give a most reliable estimation of the sedimentation rates.

9

Application of α and γ spectrometry in the 210Pb method to model sedimentation in artificial retention reservoir

Sikorski J., Bluszcz A.

Geochronometria

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2008

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Vol. 31

65-75

EN

The paper describes the application of the 210Pb method for creating a comprehensive model of sedimentation in the retention reservoir Kozłowa Góra during the 60 years of its use. The model takes into account the temporal and spatial change in the sedimentation conditions. Because of the specific conditions of the young artificial lake, the techniques available to date are not sufficient and it was necessary to modify the 210Pb method. The paper describes such modification of the method and its application to dating the sediments in the reservoir. For a young lake it is impossible to estimate the activity of authigenic 210Pb with the application of alpha spectrometry because even the oldest sediments contain allochthonous 210Pb. The determination of the activity of authigenic 210Pb in the sediments of the studied reservoir was possible only thank to gamma spectrometry. The gamma ray spectrometry consists of measurements of gamma photons emitted by 210Pb, 214Pb and 214Bi isotopes. Analysis of the 210Pb gamma spectrum line yields information about total activity of 210Pb, while the assessed activity of 214Pb and 214Bi equals to the activity of authigenic 210Pb.

10

Wykorzystanie 210Pb i metali ciężkich do oceny tempa współczesnej sedymentacji zanieczyszczonych osadów fluwialnych w dolinie górnej Warty

Łokas E., Ciszewski D., Wachniew P., Owczarek P.

Przegląd Geologiczny

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2006

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Vol. 54, nr 10

888-894

EN

River floodplains have been recognized as an important sink for suspended sediments and associated contaminants mobilized from upstream catchments. However, information on rates of overbank sedimentation within time span of several tens of years is impossible to obtain using conventional sediment traps. Measurements of the 210Pb content in floodplain sediments provide an alternative approach for obtaining estimates of medium-term (100–150 years) rates of overbank sediment deposition. The use of 210Pb method and heavy metals concentration profiles allowed to obtain retrospective estimates of recent sedimentation rates on floodplain of the Warta River (the Cracow Upland, southern Poland). The results are compared with dating of sediment layers by characteristic peaks of heavy metal concentrations. The highest sediment accretion rate, of the order of 1 cm/year, was found in a levee along river bank. Sediment deposition in flood basin is much slower and usually does not exceed 1 mm/year.

11

Recent changes in sediment accumulation rates in Adventfjorden, Svalbard

Zajączkowski M., Szczuciński W., Bojanowski R.

Oceanologia

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2004

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No. 46 (2)

217-231

EN

Recent sediment accumulation rates in Adventfjorden (Svalbard), a small subpolar fjord, were determined by 210Pb and 137Cs dating. Modern rates in the central basin decrease downfjord from 1.87 to 0.87 cm y-1 (2.6 to 1.19 g cm-2 y-1). Comparison of the modern values (1986-2001) with older ones (1963-86) reveals a marked increase in sediment accumulation rates in the last ten years. This correlates well with recent climate changes (warming and increase in precipitation). Comparison with particulate matter flux data indicates that a portion of the sediment is passed on to Isfjorden.

12

Estimating recent sedimentation rates using 210 PB on the example of morphologically complex lake (Upper Lake Raduńskie, N Poland)

Tylmann W.

Geochronometria

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2004

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Vol. 23

21-26

EN

Upper Lake Raduńskie is a classical channel lake with a typical complexity of lake basin morphology. This study presents the results of 210Pb measurements in four cores of recent sediments taken from different parts of the lake. The unsupported 210Pb activity plotted on a logarithmic scale against the cumulative dry mass decreased almost linearly. Sedimentation rates were determined from the mean slope of the profile (CF:CS model). A diversity of calculated values was significant, the highest value was found in the core RAD02/6 located in the deepest part of the lake. Both 210Pb inventories and fluxes were higher than that expected from atmospheric fallout estimated for this part of Europe. Factors influencing differences between atmospheric fallout and sediment record may include inputs from the catchment and sediment focusing, which seems to be the main reason of sedimentation rates diversity in morphologically complex lakes.

13

Testing applicability of 210Pb method to date sediments of human-made lake Kozłowa Góra

Sikorski J., Bluszcz A.

Geochronometria

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2003

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Vol. 22

63-66

EN

This paper presents results of measurements of 210Pb in sediments of the humanmade lake Kozłowa Góra. The measurements were done on the complete sediment cores taken in 1999 and covering the whole 60 years span of life of the lake. For the first time in Poland, the gamma ray spectrometry was employed, additionally to the alpha spectrometry method, what gave the opportunity to date the sediments and also to determine the sedimentation rates, and to correlate their changes with modification of the dam. Analyses of measured 210Pb radioactivity and dating based on a modified CRS model and led to a model of sedimentation that explains most of experimental results.

14

Inventory of sediments of the dammed lake in Kozłowa Góra and first measurements of 210Pb activities in the lake deposits

Sikorski J., Goslar T.

Geochronometria

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2003

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Vol. 22

55-62

EN

The dammed lake Kozłowa Góra was created in 1939, and has been utilized as a fresh-water reservoir. The lake is situated in Upper Silesia. The paper describes this artificial water reservoir, its sediments, the probes used and the sediment cores collected for analyses of activities of 210Pb. The cores of sediments have been collected in 13 sites, 6 of them along the dam. Sediment cores were gained by the freezing method. 210Pb method has been widely used in dating of lake sediments. The activity of allochthonous 210Pb decreases according to the law of radioactive decay with the half-life of T˝ = 22.26 yr. Thus its activity can be used to determine the age of sediments within the range of several half-lives (100-150 years). Here we present preliminary 210Pb measurements in sediments of dammed lake Kozłowa Góra.

15

210 Pb dating of young holocene sediments in High-mountains lakes of the Tatra Mountains

Kotarba A., Łokas E., Wachniew P.

Geochronometria

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2002

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Vol. 21

73-77

EN

Topmost sediments in two oligotrophic lakes of the High Tatra Mountains were studied in terms of sedimentological characteristics and 210 Pb dating. An alpine lake sediments are important source of information on geomorphic process activity in glacial catchments. Two different sediment transfer models are represented. In Morskie Oko lake basin majority of extreme, short lasting geomorphic events triggered on the surrounding slopes are registred in lake sediments (minerogenic laminae), while in Zelene Pleso lake only an effect of pro-longed flooding periods are to be seen. The sedimentation rates in both lakes are similar.

16

First measurements of natural radioactivities of 210Pb in the Institute of Physics, Silesian University of Technology

Goslar T., Ganowicz M., Czernik J., Sikorski J.

Geochronometria

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2000

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Vol. 18

29-34

EN

In this paper we describe the first measurements of 210Pb concentrations in sediments, performed in the Institute of Physics, Silesian University of Technology, Gliwice. The reliability of our method has been tested by the 210Pb measurements in the sediments of Lake Gościąż. The reasons for the non-monotonic profile of 210Pb in these sediments have been discussed. We also report and discuss the 210Pb measurements in the sediments formed in front of the Skeidarar glacier (Iceland).