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Article

Assessment of 137Cs and 40K Transfer Factors in Croatian Agricultural Systems and Implications for Food Safety

1
Institute for Medical Research and Occupational Health, Ksaverska Cesta 2, HR-10000 Zagreb, Croatia
2
Faculty of Dental Medicine and Health, Josip Juraj Strossmayer University of Osijek, Crkvena 21, HR-31000 Osijek, Croatia
*
Author to whom correspondence should be addressed.
Environments 2025, 12(8), 269; https://doi.org/10.3390/environments12080269 (registering DOI)
Submission received: 20 June 2025 / Revised: 30 July 2025 / Accepted: 31 July 2025 / Published: 2 August 2025

Abstract

Croatian agricultural legislation acknowledges the significance of radionuclides as pollutants in agricultural lands; however, it lacks specific thresholds or reference values for contamination levels, in contrast to other contaminants. This absence highlights the necessity for a comprehensive assessment of radionuclides across various agricultural systems in Croatia. This study investigates the transfer of radionuclides 137Cs and 40K from soil to agricultural crops throughout Croatia and estimates the consequent annual ingestion dose for the population. The samples collected comprised food crops and animal feed, with corresponding soil samples analyzed to calculate transfer factors. Activity concentrations of 137Cs exhibited regional and crop-type variability, reflecting the uneven distribution of fallout and differing soil properties. Transfer factors were found to range from 0.003 to 0.06 for 137Cs and from 0.15 to 3.1 for 40K, with the highest uptake occurring in kidney beans. The total estimated annual effective ingestion dose was calculated to be a maximum of 0.748 mSv/year for children aged 2–7, predominantly attributable to 40K. Given the homeostatic regulation of potassium in the human body, the dose associated with 137Cs poses a more significant radiological concern. These findings underscore the need for radionuclide-specific agricultural legislation in Croatia and offer a baseline for recommending reference values and informing future regulations regarding agricultural soil contamination.

1. Introduction

The uptake of long-lived radionuclides such as 137Cs and 40K from the soil to the plant by plant roots is the primary pathway for the transfer of radionuclides from soil to the human food chain [1]. Long-term monitoring of the environment has been one of the bases for assessment of the impact of radionuclides on humans through ingestion and inhalation. Part of the monitoring program is measuring 137Cs and 40K in foodstuffs, animal feed and soil in three main regions of Croatia [2]. The selected radionuclides include 137Cs, an anthropogenic radionuclide that resulted from the Chernobyl disaster. As an alkaline metal, cesium in the soil is highly accessible for uptake by plants and subsequently into the food chain. Food products represent the main route for the transfer of 137Cs from soil to humans [3]. Consequently, the EU has established specific regulations regarding 137Cs levels in food [4]. It is widely recognized that one of the factors influencing the transfer of cesium from soil to plants is the concentration of potassium in the soil [3,5,6,7]. To address potassium’s role in cesium uptake by plants, analyses of 40K were incorporated into this study. 40K is a naturally occurring radionuclide found in the environment and within human bodies. Moreover, these two radionuclides are included in this investigation as a standard element of the monitoring program, in contrast to other potentially more significant radionuclides (such as 226Ra, 210Pb, 210Po, 90Sr, etc.), concerning the estimation of a dose for humans. The presence of radionuclides in agricultural soils can lead to bioaccumulation in crops, entering the food chain and potentially exposing consumers to radiation. While Croatian agricultural legislation recognizes radionuclides as high-priority pollutants, it currently lacks specific regulatory limits or reference values for their contamination in agricultural products [8]. This contrasts with the detailed regulations established for other agricultural pollutants. Currently, many countries, including Croatia, lack explicit national thresholds for radionuclide levels in agricultural soils, particularly for anthropogenic radionuclides like 137Cs or naturally occurring ones like 40K. The overview of the current implementation of foodstuff monitoring in the EU countries is given by Mate et al. [9]. Merz et al. [10] conclude that there is a lack of harmonized international standards for acceptable levels of radionuclides in food, which can lead to public confusion and mistrust. The authors also emphasize the need for transparent, science-based and internationally coordinated guidelines to build public trust and ensure food safety [10]. The use of transfer factors can potentially fill this regulatory gap by providing a science-based method for back-calculating safe soil radionuclide activity levels. This study addresses this gap by investigating the transfer of radionuclides from soil to crops in Croatian agricultural systems.
For the purpose of evaluating the dynamics of radionuclides from soil to plants, transfer factors are used. A transfer factor is defined as the ratio of the dry weight concentration in the plants to the dry weight concentration in the specified soil layer for the uptake of any radionuclide from soil to plants [11,12]. The most extensive database of soil-to-plant transfer factors is Technical Report Series No. 472—Handbook of Parameter Values for the Prediction of Radionuclides Transfer in Terrestrial and Freshwater Environments published by the International Atomic Energy Agency in 2010 [12].
In this investigation, the existing long-term data (2010–2024) on radionuclide concentrations were used to determine the transfer factors and analyze the impact of soil properties, plant species and environmental factors on radionuclide uptake. Furthermore, we evaluated the potential risks to human health through dietary exposure by comparing the measured radionuclide concentrations in crops with existing radiation protection guidelines. The aims of this study were to estimate the transfer factors from soil to plants, both sampled during the last 14 years; to estimate the transfer factors in different regions of Croatia; and to potentially cover the gap in missing legislative limits and give recommendations on assessment of reference values for agricultural soil radioactivity.
Transfer factors were calculated for each radionuclide in each plant and foodstuff species using the ratio of radionuclide concentration in edible parts of the plant to that in the soil [13,14].
The primary limitation of this study is the varying sampling locations for both food items and soil. The sites designated for environmental radioactivity monitoring in Croatia are established by the national monitoring plan and have remained unchanged for several decades. The samples reflect different regions of Croatia and are typically not collected simultaneously. Food samples are predominantly sourced from open markets in major urban centers, while soil samples are gathered from rural areas and are consistently obtained from the same locations over the years, and they represent the region in which they are sampled. For the purposes of this study, the measurement data collected over the past 14 years can be adequate for estimating the transfer factors, with the final aim of formulating recommendations to enhance agricultural soil legislation.

2. Materials and Methods

2.1. Sampling and Laboratory Analysis

The sampling locations were established in accordance with an annual plan and program for monitoring radioactivity in the environment. This framework is delineated by the Ministry of Interior of the Republic of Croatia—Civil Protection Directorate (prior to 2019, it was overseen by the State Office for Radiological and Nuclear Protection). The sampling effort was categorized into three distinct regions: North-western and Central Croatia, Eastern Croatia and the Coastal Region. For this study, data were collected from the measurements conducted over the period from 2010 to 2024.
Food items—specifically leafy vegetables (lettuce, spinach, cabbage), tubers (potatoes), cereals (wheat) and other vegetables (kidney beans)—were obtained from open markets in major Croatian cities, reflecting the regions under study. Plant samples intended for animal feed, such as grass, lucerne and silage, were collected in proximity to the soil sampling sites or within the same relevant region. The quantity of samples collected depended on the typical water content associated with the samples, addressing losses incurred during the drying and ashing preparation phases.
Soil sampling was carried out according to the standardized procedures for studying environmental pollutants [15]. The topsoil (0–20 cm) was sampled at three (utilizing a triangular sampling design) or five points (employing a cross-sampling scheme), with each point situated 10 m apart based on the designated sampling locations. Subsamples weighing 1.5–2 kg were homogenized, and 1.5–3 kg of the final composite sample was processed further. In the laboratory, the soil samples were sieved (maximum grain size of 2 mm), dried at 105 °C for 3 days and ashed at 400 °C.
Ashed samples were packed in sealed cylindrical containers of 100 mL, 200 mL or Marinelli beakers (1 L) depending on the amount of sample. The activity concentrations of gamma-ray-emitting radionuclides, including 137Cs and 40K, were determined using gamma-ray spectrometry. The systems used in this investigation were high-purity germanium coaxial photon detectors: Ortec GMX (ORTEC/AMETEK, Oak Ridge, TN, USA), with a relative efficiency of 74.2% and a full photo peak width at half maximum of 2.24 keV at 1.33 MeV 60Co, and Ortec HPGe (Oak Ridge, TN, USA), with a relative efficiency of 21% and a full photo peak width at half maximum of 1.75 keV at 1.33 MeV 60Co. Energy and efficiency calibrations were performed with certified calibration sources of the appropriate geometry (CBSS2 MIX and MBSS2 MIX, produced by Eurostandard CZ, Czech Republic). The measurement time was at least 80,000 s, and the spectra were analyzed using the ORTEC Gamma Vision software (Gamma Vision 32, ORTEC/AMETEK, Oak Ridge, TN, USA). The typical detection limits for 137Cs and 40K were 4 Bq/kg and 0.4 Bq/kg, respectively. Validation of the gamma-ray spectrometry systems included assessments of trueness, precision/repeatability, detection limits, matrix variations and measurement uncertainties [16]. The uncertainty budget for the measurements encompassed factors such as emission probabilities, coincidence corrections, self-attenuation corrections, detector efficiencies, counting rates and sample mass (with background radiation subtracted). The laboratory operates under accreditation in accordance with the ISO/IEC 17025 standard [17].

2.2. Transfer Factors

The transfer factor (TF) is a crucial concept in the field of environmental science and radiological protection, particularly for assessing the dynamics of radionuclides from the soil into plants. Defined as the ratio of the concentration of a specific radionuclide in the edible portions of dry plants to its concentration in the dry soil sample, the transfer factor serves as an indicator of potential bioaccumulation in agricultural systems [11,16]. The transfer factors are calculated as follows:
T F = A i c r o p A i ( s o i l )
where
Ai is the activity concentration of a radionuclide I in a crop and corresponding soil sample of interest in Bq/kg.

2.3. Annual Effective Dose Calculations

The annual effective dose E from the intake of food was determined for each of the foodstuff of interest. Average values of detected activity concentrations of 137Cs and 40K for each plant group were used to estimate the annual ingestion dose. The effective doses were calculated as follows:
E = CDiAi
where
E is the effective dose in Sv;
C is the average annual per capita ingestion of food in kg (from [18]);
Di is the dose conversion factor for radionuclide I (from IAEA [19]);
Ai is the mean activity concentration of a radionuclide I in a specific vegetable of interest in Bq/kg.

3. Results and Discussion

3.1. Activity Concentrations of 137Cs and 40K in Food, Animal Feed and Soil

The results of activity concentration measurements are shown in Table 1, Table 2 and Table 3 for food, animal feed and soil, respectively. The number of samples in each food group is shown in parentheses, and the foodstuff categories are divided according to legislation [10,17]. The activity concentrations of 137Cs and 40K differ between the food groups, as expected. The results are similar to other investigations conducted in Croatia [11,20,21,22] and Austria [23].
The soil serves as a fundamental s”urce’of radionuclides for food and animal feed crops. The activity concentrations of 137Cs and 40K in soil vary at different sampling sites due to the geochemical diversity present in Croatian soils [21].
As illustrated in Figure 1a, the activity concentrations of 137Cs in topsoil samples exhibit a declining trend from 2010 to 2024. This observation is expected, given the decay characteristics of 137Cs released during the Chernobyl disaster. By 2024, approximately 38 years will have elapsed since the Chernobyl incident, suggesting that roughly 35% of the original 137Cs remains in the soil samples at present. The remaining two-thirds have undergone decay due to the natural radioactive decay process, as well as environmental factors such as soil erosion, leaching, plant uptake and bioturbation [24,25,26]. An exception to this trend is observed in the coastal regions of Croatia, which were not initially affected by the Chernobyl plume following the accident [20]. The residual effects of the Chernobyl incident and the global fallout are also evident in feed samples from the eastern part of Croatia, as depicted in Figure 2a. In contrast, the activity concentrations of natural 40K have shown a gradual increase over the past 14 years (see Figure 2b).

3.2. Transfer Factors from Soil to Plant

Transfer factors were estimated using Equation (1) for each distinct food category and specific radionuclide present. The results, which include mean values, standard deviations, as well as both minimum and maximum recorded values, are presented in Table 4. The transfer factors for animal feed are shown in Table 5.
It is established that various soil characteristics influence the transfer factors [27,28]. However, for the aims of this study, the precise values of transfer factors hold less significance. The estimation of values relevant to each region of interest is of greater importance. The limitations of these estimations are characterized by significant uncertainties; however, the soil sampling sites have remained consistent for over 50 years and accurately reflect the typical soil types of the region in question. This consistency also applies to the samples of foodstuffs and animal feed.
Notably, the transfer factors associated with kidney beans exhibit the highest recorded values in relation to the activity concentrations observed within foodstuffs and the soil samples. This significant finding indicates that kidney beans possess a remarkable capacity to accumulate considerable amounts of radionuclides from the surrounding soil, especially in samples sourced from the coastal region of Croatia (Figure 3). Such a phenomenon undoubtedly warrants further investigation in order to understand the mechanisms involved. However, the values of transfer factors for other foodstuffs are similar to the values from other studies [11,12].

3.3. Effective Dose from Ingestion

The annual effective dose was determined for four distinct age categories in accordance with regulatory guidelines [18]: children aged 2–7 years, those aged 7–12 years, adolescents aged 12–17 years and adults over 17 years of age. Table 6 presents the contributions of different food groups to the dose, calculated using Equation (2). The consumption rates are provided by the guidelines [18]. The maximum total dose derived from both 137Cs and 40K is 0.748 mSv/year for the 2–7-year-old group, which remains below the 1 mSv/year limit recommended by the International Commission on Radiological Protection [27]. Given the elevated activity concentrations of 137Cs and 40K found in kidney beans, it is anticipated that the most significant contribution to the dose will arise from kidney beans, which account for an average contribution of 43%, as illustrated in Figure 4. It is important to note that 40K contributes significantly to the total dose, as it is a naturally occurring radionuclide that is subject to homeostatic regulation in the human body. Unlike anthropogenic radionuclides, such as 137Cs, the biological system maintains a relatively stable internal potassium concentration regardless of dietary intake, limiting the health relevance of its radiological dose. For this reason, ICRP and other international bodies typically do not consider 40K a regulatory concern in routine radiological protection evaluations [29]. In this study, while the maximum ingestion dose approaches 0.748 mSv/year, over 90% of this dose originates from 40K. The 137Cs dose component, estimated at 0.009 mSv/year, is more relevant for health risk assessment and regulatory consideration. This distinction has implications for legislative frameworks. Merz et al. [10] highlight that international legislation in post-nuclear-accident contexts often suffers from inconsistencies in threshold values and a lack of harmonized standards, especially regarding which radionuclides should be subject to regulation. Their study underscores the importance of distinguishing between natural and artificial radionuclides not only in public risk communication but also in the design of intervention levels and food trade policies.
One of the aims of this study was to address the absence of legislative thresholds and to propose recommendations for evaluating the reference values concerning radioactivity in agricultural soils. The intent was to ascertain whether long-term monitoring data could serve as a foundational basis for this purpose. Notwithstanding the study’s inherent limitations, our findings aligned closely with those of prior research conducted in Croatia, providing data that could act as a preliminary basis for developing recommendations for future reference values. The Ordinance on the Protection of Agricultural Land from Pollution [8] recognizes radionuclides as contaminants; however, it does not delineate specific reference values, indicating that radiation protection legislation serves as the primary framework. Nevertheless, through the methodology employed in this study, coupled with a more thorough investigation, the potential for introducing different reference values becomes evident.
One of the main motivations of this study was to support the formulation of guidelines or reference values for radionuclide concentrations in Croatian agricultural soils. Although the current Croatian legislation acknowledges radionuclides as contaminants [8], it does not provide specific thresholds. Based on our findings, we propose the following recommendations: i. Establish soil reference levels for 137Cs. Utilizing our transfer factor data and ingestion dose estimates, preliminary screening levels for 137Cs in soil could be implemented in a way that would align them with EU food safety thresholds (e.g., 600 Bq/kg for general food). Specifically, soils in sensitive crop-producing regions with 137Cs concentrations exceeding 20–30 Bq/kg should be subject to monitoring; ii. Given the biological homeostatic regulation of 40K, it should not be prioritized in regulatory frameworks. Anthropogenic radionuclides such as 137Cs and 90Sr or plutonium isotopes are contingent on the availability of future data; iii. The transfer factors calculated in this and other studies present a pragmatic approach to back-calculating permissible soil activity concentrations. It is vital to standardize the transfer factor methodology, which necessitates co-located soil and crop sampling, to ensure consistency. These proposals are intended to serve as a foundational basis for further expert dialog and legislative advancements aimed at enhancing food safety and environmental protection within Croatia.

4. Conclusions

The transfer factors from soil to plants can serve as an indicator of potential soil contamination with radionuclides and can provide valuable insights into environmental safety. The results obtained from this study demonstrate that the existing gaps in legislative documents can be effectively addressed by conducting an analysis of long-term monitoring data regarding the levels of radioactivity present in the environment. The findings from this study prove to be instrumental in informing the formulation and development of more effective regulations aimed at managing radionuclide contamination in agricultural products, thereby enhancing overall food safety and protecting public health in Croatia. Furthermore, these findings hold potential relevance for other countries that are confronting similar challenges related to radionuclide contamination in their agricultural systems, ultimately fostering a broader dialog on food safety and environmental health on an international scale.

Author Contributions

T.B.: Writing—Original draft, Data analysis, Writing—Editing; B.P.: Writing—Review and editing, Methodology, Data analysis; D.H.: Data analysis, Writing—Review; S.S.: Original idea, Conceptualization, Writing. All authors have read and agreed to the published version of the manuscript.

Funding

Funded by the European Union—NextGenerationEU under the project “Transforming bio-waste to innovative hydroponic solutions—Was2Grow” No. NPOO.C3.2.R3-I1.04.0143. The views and opinions expressed are solely those of the authors and do not necessarily reflect the official position of the European Union or the European Commission. Neither the European Union nor the European Commission can be held responsible for them.

Data Availability Statement

The data of this study are available from the corresponding author upon reasonable request.

Acknowledgments

The authors would like to acknowledge the staff of the Division for Radiation Protection of the Institute for Medical Research and Occupational Health who contributed to sampling, sample preparation and analysis. During the preparation of this manuscript, the authors used Mendeley Desktop (Version 1.19.8) for the purposes of reference formatting. The authors have reviewed and edited the output and take full responsibility for the content of this publication.

Conflicts of Interest

The authors declare that they have no competing interests.

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Figure 1. Activity concentrations of 137Cs (a) and 40K (b) in soil samples in three regions of Croatia.
Figure 1. Activity concentrations of 137Cs (a) and 40K (b) in soil samples in three regions of Croatia.
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Figure 2. Activity concentrations of 137Cs (a) and 40K (b) in animal feed samples in Eastern Croatia. The lines represent the trend.
Figure 2. Activity concentrations of 137Cs (a) and 40K (b) in animal feed samples in Eastern Croatia. The lines represent the trend.
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Figure 3. Transfer factors in foodstuff samples per plant group and region. Columns represent the mean value, and error bars represent the minimum and maximum values.
Figure 3. Transfer factors in foodstuff samples per plant group and region. Columns represent the mean value, and error bars represent the minimum and maximum values.
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Figure 4. Contribution to the annual effective dose per type of food.
Figure 4. Contribution to the annual effective dose per type of food.
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Table 1. Activity concentrations of 137Cs and 40K (Bq/kg) in food per plant group. The mean value is listed with standard deviation.
Table 1. Activity concentrations of 137Cs and 40K (Bq/kg) in food per plant group. The mean value is listed with standard deviation.
RegionFoodstuff Group
(Number of Samples)
Activity Concentration (Bq/kg)
137Cs40K
North-western and
Central Croatia
Leafy vegetables (42)Mean0.04 ± 0.0583 ± 38
Min–Max0.008–0.21532–225
Tubers (14)Mean0.05 ± 0.05124 ± 20
Min–Max0.01–0.1697–159
Cereals (12)Mean0.08 ± 0.01140 ± 63
Min–Max0.06–0.1090–295
Kidney beans (13)Mean0.17 ± 0.13535 ± 290
Min–Max0.04–0.53252–1440
Eastern CroatiaLeafy vegetables (32)Mean0.05 ± 0.08120 ± 92
Min–Max0.009–0.39733–553
Tubers (12)Mean0.1 ± 0.1158 ± 69
Min–Max0.02–0.42102–342
Cereals (16)Mean0.12 ± 0.12140 ± 29
Min–Max0.02–0.3697–176
Kidney beans (12)Mean0.17 ± 0.13475 ± 36
Min–Max0.03–0.48431–531
Coastal CroatiaLeafy vegetables (44)Mean0.06 ± 0.1175 ± 24
Min–Max0.009–0.62259–106
Tubers (15)Mean0.03 ± 0.01123 ± 22
Min–Max0.01–0.0697–164
Cereals (6)Mean0.14 ± 0.12171 ± 109
Min–Max0.03–0.37108–392
Kidney beans (11)Mean0.41 ± 0.27674 ± 92
Min–Max0.10–1.01376–1270
Table 2. Activity concentrations of 137Cs and 40K in animal feed sampled in Eastern Croatia region. The mean value is listed with standard deviation.
Table 2. Activity concentrations of 137Cs and 40K in animal feed sampled in Eastern Croatia region. The mean value is listed with standard deviation.
RegionAnimal Feed
(Number of Samples)
Activity Concentration (Bq/kg)
137Cs40K
Eastern CroatiaLucerne (16)Mean0.7 ± 1.1807 ± 522
Min–Max0.1–4.6106–1420
Silage (16)Mean0.3 ± 0.3369 ± 378
Min–Max0.008–1.300130–1720
Grass (13)Mean0.4 ± 0.3935 ± 346
Min–Max0.1–1.3530–1670
Table 3. Activity concentrations of 137Cs and 40K in soil samples. The mean value is listed with standard deviation.
Table 3. Activity concentrations of 137Cs and 40K in soil samples. The mean value is listed with standard deviation.
RegionActivity Concentration (Bq/kg) in Soil
137Cs40K
North-western and Central CroatiaMean16 ± 6513 ± 120
Median15 ± 6512 ± 120
Min6.9 ± 0.2325 ± 4
Max28.7 ± 0.2822 ± 5
Eastern CroatiaMean7 ± 5599 ± 98
Median6 ± 5619 ± 98
Min0.7 ± 0.6370 ± 3
Max18.1 ± 0.1736 ± 3
Coastal CroatiaMean10 ± 5599 ± 98
Median10 ± 5619 ± 98
Min2.2 ± 0.2370 ± 3
Max20.5 ± 0.2736 ± 3
Table 4. Transfer factors in foodstuff samples per plant group and region of Croatia. The mean value is listed with standard deviation.
Table 4. Transfer factors in foodstuff samples per plant group and region of Croatia. The mean value is listed with standard deviation.
RegionFoodstuff Group
(Number of Samples)
Transfer Factors
137Cs40K
North-western and
Central Croatia
Leafy vegetables (42)Mean0.003 ± 0.0030.16 ± 0.08
Min–Max0.0003–0.01630.05–0.42
Tubers (14)Mean0.003 ± 0.0040.25 ± 0.06
Min–Max0.0004–0.01210.18–0.36
Cereals (12)Mean0.005 ± 0.0030.29 ± 0.12
Min–Max0.003–0.0130.15–0.52
Kidney beans (13)Mean0.010 ± 0.0081.0 ± 0.5
Min–Max0.001–0.0370.6–2.5
Eastern CroatiaLeafy vegetables (32)Mean0.01 ± 0.010.15 ± 0.15
Min–Max0.0009–0.05240.06–0.89
Tubers (12)Mean0.02 ± 0.030.30 ± 0.23
Min–Max0.003–0.070.17–0.93
Cereals (16)Mean0.02 ± 0.020.22 ± 0.06
Min–Max0.004–0.0700.15–0.38
Kidney beans (12)Mean0.03 ± 0.050.8 ± 0.1
Min–Max0.006–0.1670.6–1.1
Coastal CroatiaLeafy vegetables (44)Mean0.006 ± 0.0090.35 ± 0.18
Min–Max0.0001–0.05410.1–1.0
Tubers (15)Mean0.004 ± 0.0040.57 ± 0.30
Min–Max0.0005–0.01480.2–1.2
Cereals (6)Mean0.02 ± 0.011.2 ± 0.8
Min–Max0.006–0.0420.6–2.8
Kidney beans (11)Mean0.06 ± 0.063.1 ± 2.6
Min–Max0.01–0.210.8–8.9
Table 5. Transfer factors in animal feed from Eastern Croatia. The mean value is listed with standard deviation.
Table 5. Transfer factors in animal feed from Eastern Croatia. The mean value is listed with standard deviation.
RegionAnimal Feed
(Number of Samples)
Transfer Factors
137Cs40K
Eastern CroatiaLucerne (16)Mean0.16 ± 0.251.4 ± 1.0
Min–Max0.013–0.9540.2–2.9
Silage (16)Mean0.06 ± 0.620.6 ± 0.6
Min–Max0.002–2.850.2–2.9
Grass (13)Mean0.10 ± 0.111.6 ± 0.6
Min–Max0.1–1.30.02–0.42
Table 6. Annual effective dose (in mSv/year) from ingestion of foodstuffs (leafy vegetables, tubers, cereals and kidney beans) for different age groups.
Table 6. Annual effective dose (in mSv/year) from ingestion of foodstuffs (leafy vegetables, tubers, cereals and kidney beans) for different age groups.
Annual Effective Dose (mSv/year)
Age Group2–7 y.o.7–12 y.o.12–17 y.o.<17 y.o.
Leafy vegetables0.0140.0110.0080.007
Tubers0.1280.0970.0560.046
Cereals0.2530.1860.1260.103
Kidney beans0.3540.2550.1490.139
Total0.7480.5490.3390.296
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MDPI and ACS Style

Bituh, T.; Petrinec, B.; Hasenay, D.; Stipičević, S. Assessment of 137Cs and 40K Transfer Factors in Croatian Agricultural Systems and Implications for Food Safety. Environments 2025, 12, 269. https://doi.org/10.3390/environments12080269

AMA Style

Bituh T, Petrinec B, Hasenay D, Stipičević S. Assessment of 137Cs and 40K Transfer Factors in Croatian Agricultural Systems and Implications for Food Safety. Environments. 2025; 12(8):269. https://doi.org/10.3390/environments12080269

Chicago/Turabian Style

Bituh, Tomislav, Branko Petrinec, Dragutin Hasenay, and Sanja Stipičević. 2025. "Assessment of 137Cs and 40K Transfer Factors in Croatian Agricultural Systems and Implications for Food Safety" Environments 12, no. 8: 269. https://doi.org/10.3390/environments12080269

APA Style

Bituh, T., Petrinec, B., Hasenay, D., & Stipičević, S. (2025). Assessment of 137Cs and 40K Transfer Factors in Croatian Agricultural Systems and Implications for Food Safety. Environments, 12(8), 269. https://doi.org/10.3390/environments12080269

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