Abstract
We studied activity concentrations of radionuclides in the Kopački Rit Nature Park using mosses as bioindicators. This area of intact nature is at the tripoint of Croatia, Hungary, and ...Serbia, being located basically at the centre of the middle Danube River basin. Therefore, it can be easily affected by airborne pollution from various locations in the Middle Europe and beyond. The goal of our research was to assess whether the Park could serve as a location where any new radioactive contamination could be sensitively detected, which implied a necessity for low activity concentrations at the present time. Our gamma-ray spectrometry revealed the presence of only one anthropogenic gamma emitter, that is,
137
Cs. Its activity concentration in the mosses ranged from 0.7 to 13.1 Bq kg
−1
, being low indeed. Another radionuclide in our focus was
210
Pb. Generally, its elevated concentrations may signify ecologically undesirable human activities that involve naturally occurring radioactive matter. The activity concentration of
210
Pb in the mosses was in the range from 183 to 690 Bq kg
−1
. This did not depart from the results of other similar studies and was again low enough for a detection of possible excess amounts of this radionuclide in the future.
Papuk Nature Park, unlike most similar parks and preserves in the world, contains active quarries. Quarries dig stone from the ground, creating dust and exposing deeper, potentially more radioactive ...layers. Since the forest trails in the Park lead right up to the quarries, we believed it was important to determine the radiological impact of the quarries on the Park environment. We measured ambient dose rate equivalent
(10) and sampled moss at 26 Park locations along two of four quarries, along the road between them, and near Lake Orahovac, a very popular tourist destination close to the quarries. Moss is a standard bioindicator of exposure to heavy metals, including radionuclides. Using-gamma ray spectrometry we determined the activity concentration of
Cs and of representative naturally occurring radionuclides –
U,
Ra,
Pb,
Th, and
K – in sampled moss.
(10) at selected locations was similar to the background
(10) measured continuously all over Croatia. The ranges of measured activity concentrations of
Cs and naturally occurring radionuclides in moss did not differ significantly from other parts of Croatia and nearby countries.
Phosphogypsum (PG) is a waste by-product (residue) originating from the production of phosphoric acid and phosphate fertilisers. PG contains chemical and radioactive impurities, which is why it is ...mostly stockpiled in controlled areas. Worldwide, only about 15 % of PG is recycled or reused. Today, policies and business strategies prioritise sustainable development through circular economy, which certainly includes PG. This provides new opportunities for Croatia to manage its PG and make an effort to use it as an additive in different industries, such as agriculture and construction. Due to its chemical and radiological properties, PG can potentially cause problems for the environment and human health. Hence, before using PG, detailed knowledge of potential hazards is necessary to protect people and the environment. The aim of this review is to summarise available data on Croatian PG, compare them with other countries, and to identify knowledge gaps and the lack of data on potential hazardous substances in PG in order to assess the opportunities of using PG in Croatia.
gamma ray spectrometry was developed to quickly measure large areas of land following nuclear accidents. However, a proper calibration of detectors for
measurements is a long and complicated process. ...One tool designed to make this calibration quick is the InSiCal software. We compared 5,000 s
measurements with two different HPGe detectors calibrated using the InSiCal software and laboratory measurements of samples collected at the same locations. Our findings suggest that
gamma spectrometry using InSiCal software can provide reasonably accurate data, but some improvements are needed.
The aim of this study was to characterise the elemental and radiological composition of strawberry tree (Arbutus unedo L.) leaves and tea preparations and compare it with commercial Uvin H herbal ...mixture, widely used in treatment of urinary tract infections. The concentration of 17 elements and the activity concentration of selected radionuclides were measured in strawberry tree leaves/Uvin H herbal mixture, as well as in herbal tea prepared by infusion or decoction of leaves for 5 or 10 min. In both leaves and tea preparations, Ca, K, Mg, and Na were the most abundant elements, while the lowest levels were measured for As, Co, Mo, and Se. Only
Cs and
K were detected in analysed leaves/herbal mixture, while the activity of radionuclides in tea preparations was below the detection limit. The maximum possible health benefits can be obtained by a 10-min decoction of leaves, which resulted in the highest total phenolic content and antioxidant activity and levels of K, Ca, Mg, Na, Fe, Mn, and Se in comparison to the other preparation methods evaluated in this study. The calculated intake of potentially toxic elements and radionuclides does not represent a health risk to consumers.
There are few studies related to the radionuclide remediation options, which comply to the demands of the environmentally non-destructive physical remediation methods. So far, most of the research ...was conducted on the phytoremediation capacity of different energy crops, as well as the established miscanthus hybrids which involved metal and heavy metal contaminants. Hence, the objective of this research was the radioecological characterization of the examined agroecosystem, including the initial source of the radionuclides (soil) as well as different miscanthus hybrids grown on the same soil. The results have shown that the radioactive content of soil was similar to the global averages. All measurements of the activity concentration of 137Cs in miscanthus samples were below the detection limits. There is also an indication that 210Pb is leaching into the lower layers (or is being taken up by miscanthus plant from the upper layers). Moreover, transfer factors (TFs) for radionuclides, as a more precise parameter for evaluating the phytoremediation potential, were calculated; the TFs were found to be very low for 226Ra (≤0.07), TFs for 40K (≤0.39) and for 232Th (≤0.21) were in the lower limits, whereas the TFs for 238U were found to be the highest (≤0.92). For 210Pb, the TFs were not calculated, since the expectation was that a significant part of the measured quantity came from the air, and not through the soil. Having in mind the sustainability and the circularity aspect of the radionuclide phytoremediation system, the appropriate management method should be applied for the disposal and utilization of the biomass contaminated with radionuclides. This research has shown that the radiological content in miscanthus is high enough and the ash content is low enough that miscanthus ash could be considered as a NORM (Naturally Occurring Radioactive Material), and it can be further used for the construction industry (i.e. concrete, tiles), in mixtures with other materials with certain limitations, similar to the utilization of ash from other sources such as coal or wood.
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The assessment of environmental radioactivity much relies on radionuclide content in soil. This stems from the significant contribution of soil to both external and internal exposure to ionising ...radiation via direct emission of gamma radiation and soil-to-plant radionuclide transfer, respectively. This motivated us to carry out a systematic research on the radioactivity of soil in Croatia to obtain relevant data that can be used as a basis for understanding the related effects of geomorphological, biogeographical, and climatological properties of the environment. We collected samples of the surface layer of uncultivated soil (0–10 cm) at 138 sites from all over the country and measured them for radionuclide activity concentrations by means of high-resolution gamma-ray spectrometry. This resulted in radioactivity maps containing data on activity concentrations of representative radionuclides in the environment. In this paper, which is the first in our two-part presentation, we focus on the naturally occurring
Th and
U decay chains and their correlations with the diversity of Croatian regions. For both of the chains, activity concentrations were the highest in the Dinaric region, the lowest in the Pannonian region, and intermediate in the Adriatic region. Relatively high concentrations of
Ra in the soil of the Dinaric region implied a possibility of an enhanced emanation of its progeny
Rn into the air. Activity concentrations of
Pb were additionally elevated in areas with dense vegetation, most probably due to an atmospheric deposition of airborne
Pb onto the surface of plants and their eventual decomposition on the ground.
Fly bioash (FBA) as a by-product of biomass-fuelled facilities exhibits alkaline properties and is enriched with phytonutrients, thereby offering the potential to effectively ameliorate acidic and ...nutrient-deficient soils. However, concerns about health risks due to a potential FBA radioactive contamination are still not well studied, notably under field conditions. This study examined pH changes and concentrations of natural (238U, 232Th, 226Ra, 40K) and anthropogenic (137Cs) radionuclides after application of very alkaline (pH > 12) FBA in: (i) highly acid (pHKCl = 4.1) Luvisol and (ii) sunflower (Helianthus annuus L.) seeds, grown in organic farming and rain-fed conditions. FBA (originated from a modern cogeneration, fuelled on certified deciduous forest wood chips) was applied at increasing doses; 0, 4.5, 8.6, 13, and 17.2 t/ha. After 54 months of application, FBA significantly increased soil pHKCl by up to 1.8 unit and the seed yield by 15%, compared with no amended Control, without compromising soil electrical conductivity (salinity). The activity concentrations (Ac) of all observed radionuclides, measured using high-resolution gamma-ray spectrometry, were not altered under FBA application, neither in the surface (0–30 cm) Luvisol horizon nor in the sunflower seed. Moreover, the Ac of 238U, 232Th, and 137Cs in the seed were below detection limit, whereas the Ac of 40K and 226Ra were lower by up to 2.6 and 61 times, respectively, than their corresponding Ac in the soil treatments. The radiological footprint of FBA exhibited lower Ac for most of the observed radionuclides compared with both (i) Croatian non-arable topsoils (with reductions of 238U 3.6 times, 232Th 1.8 times, 226Ra 1.7 times, and 137Cs 1.5 times) and (ii) widely used mineral N/P/K fertilisers in conventional agroecosystems (with reductions of 238U 12.5 times; 226Ra 1.3 times, and 40K 2.4 times). Our findings provide evidence that the application of FBA as a soil conditioner does not pose radiological health or environmental risks, contributing to more sustainable agri-food production and circular bioeconomy. However, it is essential to conduct further studies to comprehensively investigate the effects of FBA application on soil and crop quality across diverse environmental conditions and extended spatiotemporal scales.
We took samples of uncultivated soil from the surface layer (0–10 cm) at 138 sites from all over Croatia and measured their radionuclide activity concentrations with high-resolution gamma-ray ...spectrometry. This second part of our report brings the results on
K and
Cs to complement those on the
Th and
U decay chains addressed in the first part. Together they give the most complete picture of radioactivity of Croatian soil so far. Activity concentrations of
K were the highest in the Pannonian region, and there was an opposite trend for
Cs. We found that the concentrations of
Cs tended to increase with altitude, annual precipitation, and vegetation density. The concentration ratio of
Cs and K in soil, which indicates the potential for
Cs entering food chains via uptake by plants, was the lowest in agriculturally important areas in the east of the Pannonian region. In addition, we used the obtained results on activity concentrations to calculate the related absorbed dose rate as a measure of external exposure to ionising radiation from soil. The sum of the absorbed dose rates for naturally occurring radionuclides and
Cs showed that external exposure was generally the highest in the Dinaric region and Istrian Peninsula.
Fosfogips (FG) otpadni je nusproizvod (rezidua) koji potječe iz proizvodnje fosforne kiseline i fosfatnih mineralnih gnojiva. FG je kontaminiran kemijskim i radioaktivnim tvarima, stoga se uglavnom ...odlaže na kontroliranim odlagalištima. U svijetu se samo oko 15 % FG-a reciklira i ponovno koristi. U današnje vrijeme, političke i poslovne strategije stavljaju na prvo mjesto održivi razvoj kroz kružno gospodarstvo, a tu svoje mjesto može pronaći i FG. Time se stvaraju nove prilike u Republici Hrvatskoj za korištenje FG-a kao aditiva u različitim industrijama, od poljoprivrede do građevinske industrije. Zbog svojih kemijskih i radioloških svojstava, korištenje FG-a može potencijalno prouzročiti probleme za okoliš i ljudsko zdravlje. Stoga je prije korištenja nužno detaljno znanje o potencijalnim opasnostima FG-a kako bismo zaštitili ljude i okoliš. Cilj je ovoga preglednog rada sažeti dostupne podatke o FG-u u Republici Hrvatskoj, usporediti ih sa svjetskim podatcima i prepoznati nedostatke i manjak podataka o riziku koji nose potencijalno opasne tvari u FG-u.
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