Gross alpha and beta activity concentrations in spring waters in Balaton Upland, Hungary

Assessment of physicochemical properties and radioactivity in groundwater at households living in bac Lieu province, vietnam

This paper presents findings on groundwater physiochemical composition and radioactivity levels in households in Bac Lieu province, Vietnam. Through discriminant analysis, it was observed that groundwater quality exhibits spatial variations corresponding to saline intrusion zones. The paired-samples T-tests revealed significantly different ratios of Ra-224, Ra-226, and Ra-228 isotopes between Na-Cl and Ca-Na-HCO3 water types. All three water types had a ratio of Ra-226/Ra-228 of approximately one, indicating the presence of groundwater aquifers beneath the crust and fluvial marine sediment. Furthermore, strong associations between sulfate and calcium suggest that CO2 enrichment in groundwater aquifers indicates anoxic aquatic environments. Twenty-five of the thirty-three evaluated samples exceeded the national technical regulations for domestic water quality with parameters such as chloride, sulfate, sodium, gross alpha, or total dissolved solids. Fifteen samples exceeded gross alpha's allowable contamination threshold of 0.1 Bq/L. The combination of Ra-226 and Ra-228 did not surpass the U.S. Environmental Protection Agency's recommended limit of 0.185 Bq/L. However, nineteen samples exhibited annual committed effective doses of radium isotopes for infants that exceeded the WHO recommendation of 0.1 mSv/year.

Assessment of radiation exposure and public health before and after the operation of Sanmen nuclear power plant

Introduction

Sanmen nuclear power plant (SNPP) operates the first advanced passive (AP1000) nuclear power unit in China.

Methods

To assess the radiological impacts of SNPP operation on the surrounding environment and the public health, annual effective dose (AED) and excess risk (ER) were estimated based on continuous radioactivity monitoring in drinking water and ambient dose before and after its operation during 2014-2021. In addition, the residents' cancer incidence was further analyzed through authorized health data collection.

Results

The results showed that the gross α and gross β radioactivity in all types of drinking water were ranged from 0.008 to 0.017 Bq/L and 0.032 to 0.112 Bq/L, respectively. The cumulative ambient dose in Sanmen county ranged from 0.254 to 0.460 mSv/y, with an average of 0.354 ± 0.075 mSv/y. There is no statistical difference in drinking water radioactivity and ambient dose before and after the operation of SNPP according to Mann-Whitney U test. The Mann-Kendall test also indicates there is neither increasing nor decreasing trend during the period from 2014 to 2021. The age-dependent annual effective doses due to the ingestion of drinking water or exposure to the outdoor ambient environment are lower than the recommended threshold of 0.1 mSv/y. The incidence of cancer (include leukemia and thyroid cancer) in the population around SNPP is slightly higher than that in other areas, while it is still in a stable state characterized by annual percentage changes.

Discussion

The current comprehensive results show that the operation of SNPP has so far no evident radiological impact on the surrounding environment and public health, but continued monitoring is still needed in the future.

Radiological investigation of natural carbonated spring waters from Eastern Carpathians, Romania

The current study presents a radiological water-quality assessment on 64 spring water samples from four Romanian counties. The study area is abundant in CO2-rich spring waters consumed by locals and tourists. Gross alpha activities ranged between 21 ± 2 and 7530 ± 658 mBq L−1, with 27% of the samples exceeding the WHO threshold. Gross beta values ranged from 40 ± 2 to 5520 ± 430 mBq L−1, with 29% exceeding the recommended values. Radionuclide activities fluctuated between 0.6 ± 0.08 and 81 ± 6 Bq L−1 for 222Rn, 15 ± 2 to 1154 ± 112 mBq L−1 for 226Ra, and from 18 ± 2 to 64 ± 5 mBq L−1 for 210Po. The annual effective doses attributed to radium varied between 0.002 and 0.23 mSv yr−1.

Risk assessment of drinkable water sources using gross alpha and beta radioactivity levels and heavy metals

The increase in economic activities as a result of population surge in Dutsin-Ma has culminated into increase in waste and environmental quality degradation. Hence, this study examined the risk associated with different drinking water sources (dam water (DM), borehole water (BW), Hand dug well water (WW) and tap water (TW)) in Dutsin-Ma, Katsina using concentrations of gross alpha (α) and gross beta (β) activity, and heavy metals cadmium (Cd) and lead (Pb) in the water. A total of Thirty six (36) samples were collected from the study area. Standard methods were deployed for the determination of pH, concentration of gross alpha and gross beta activity and concentrations of Cd and Pb in the water samples were done using chemical fraction method. The results of the pH showed values not within the recommended limits for drinking water quality with exception of 8.30 (WW). Also, the measured activity concentrations of gross alpha in all water samples are below 0.1 Bq/L with few exceptions, while the measured activity concentrations of gross beta in 50% of the total water samples collected are higher than 1.0 Bq/L permissible limit. The mean annual dose equivalent all the water sources is higher than 0.1 mSv recommended dose for radionuclides in water, hence the life cancer risk assessment showed higher values, indicating the water are unsafe for drinking. The results in this study showed that Cd and Pb in all the water fractions (mobile, dissolved, total and particulate) are above the WHO recommended limit of 0.003 and 0.01 mg/L in drinking water. Similarly, the hazard index (HI) for the water samples are greater than one (1), hence, a possible concern for potential carcinogenic effect for consumer of the water sources.

Simultaneous Determination of Gross Alpha/Beta Activities in Groundwater for Ingestion Effective Dose and its Associated Public Health Risk Prevention

This paper presents information on the gross alpha and gross beta activity concentrations of two hundred twenty-six groundwater samples collected by gas flow proportional counters in southern Vietnam. The gross alpha results in the water samples ranged from 0.024 to 0.748 Bq L^-1 with a mean of 0.183 ± 0.034 Bq L^-1, and the gross beta results in the water samples ranged from 0.027-0.632 Bq L^-1 with a mean of 0.152 ± 0.015 Bq L^-1. The values obtained in this work were compared with those previously published for various regions or countries. Next, untreated and treated groundwater samples were analyzed to assess their influences on the treatment process. The results showed that there were differences in the minimum detection concentrations and the mean activity values between the untreated and treated groundwater samples (The p-value of the mean comparison tests is significant with p < 0.05). In both sample groups, there was a strong positive correlation of the gross alpha versus the gross beta results (r > 0.6). This means that among the radionuclides, the major sources of beta radiation are uranium and thorium decay series radionuclides. Finally, the annual effective dose for adults (>17 years) was calculated based on the assumption that major radionuclides have the highest effective dose conversion factors. In general, the results for Pb-210, Ra-226, and Ra-228 were observed to be lower than the recommended reference values established by the World Health Organization and the International Atomic Energy Agency, except for the value of Po-210.

Transient nature of riverbank filtered drinking water supply systems - A new challenge of natural radioactivity assessment

In Hungary the drinking water supply is mainly based on groundwater, in which radionuclides are common components. Since the mobility of the most common radionuclides, uranium and radium, is strongly influenced by the geochemical conditions, knowledge on the geochemical parameters of water is required. This depends on the flow system and the flow regime. Therefore, hydrogeology has a crucial role in revealing the origin of elevated activity concentrations. This research presents a case study in Hungary where the drinking water supply is provided by bank filtered and karst wells. In most of the wells of the research area the gross alpha values are above the screening level, 0.1 Bq L^-1. The aim of this study is to determine which radionuclides may cause the elevated radioactivity and explain their occurrence using the hydrogeological approach. All samples of the study were analysed for (U-238+U-234), Ra-226, Rn-222. Alpha spectrometry applied on Nucfilm discs was used to measure the uranium and radium activity while radon activity was determined by liquid scintillation. The study revealed the correlation between the river water level fluctuation and the uranium content of the wells. The results of this study highlighted the transient nature of river bank filtered systems, which should be taken into account in the monitoring and water supply strategy.

Radioactivity and hydrochemical properties of certain thermal Turkish spa waters

The study aims to determine the radioactivity levels of thermal waters which have been used seasonally or permanently in spas for therapeutic intentions. Samples were collected from spas in different regions of Turkey. Some radionuclides (⁴⁰K, ²³²Th, ²²⁶Ra, ¹³⁷Cs), gross alpha (GA) and gross beta (GB) activities, and physical and some chemical parameters were measured. Gamma radiation measurements for ²²⁶Ra, ²³²Th and ⁴⁰K radionuclides were performed by using a high purity germanium (HPGe) detector. The results of the gamma spectrometry ranged from 1.385 to 11.025 Bql^-1 for ²²⁶Ra, <minimum detectable activity to 3.477 Bql^-1 for ²³²Th and 9.679 to 36.989 Bql^-1 for ⁴⁰K. GA and GB activity concentrations were detected by using ultra-low level α/β counter. The GA and GB activity ranged from 43 to 3,182 mBql^-1 and 54 to 1,950 mBql^-1, respectively. Based on calculated annual effective dose equivalent, the total dose originated mostly from ²²⁶Ra and slightly from ⁴⁰K. Furthermore, waters with high Cl content were enriched with ⁴⁰K, ²²⁶Ra isotopes, and the source of GA and GB activity in these waters was mostly ²²⁶Ra. Strong high positive correlation between Cl, ²²⁶Ra and total dissolved solids in Cl-enriched samples indicated that the nuclides formed from dissolved minerals in these waters.

Radioactivity measurements and risk assessments of spa waters in some areas in Turkey

The current study presents the results of the activity of radionuclides in spa waters, and evaluates their radiological influences on the population consuming these waters in the Central and Eastern Black Sea regions of Turkey. Since these waters are used for therapy and consumption purposes unconsciously, their radiological impact on the people was computed by taking into consideration the annual intake through ingestion of ²²⁶Ra, ²³²Th, ⁴⁰K, ¹³⁷Cs and ²²²Rn. The mean activities were estimated to be 11.35 for gross alpha, 6.23 for gross beta, 2.96 for ²²⁶Ra, 0.42 for ²³²Th, 0.069 for ¹³⁷Cs, 0.19 for ⁴⁰K, and 267 Bq L^-1 for ²²²Rn, respectively. The estimated effective doses from spa water were found to be 49.77 µSv a^-1 (²²⁶Ra), 5.95 µSv a^-1 (²³²Th), 0.07 µSv a^-1 (¹³⁷Cs), 0.83 µSv a^-1 (⁴⁰K) and 56.03 µSv a^-1 (²²²Rn). These values were evaluated and compared with related verified values from literature. Also, physico-chemical characterizations of spa water samples considered in the current study were investigated. This study would be useful for consumers and official authorities for the assessment of radiation exposure risk due to usage of the considered spa waters.

(238)U and total radioactivity in drinking waters in Van province, Turkey

As part of the national survey to evaluate natural radioactivity in the environment, concentration levels of total radioactivity and natural uranium have been analysed in drinking water samples. A survey to study natural radioactivity in drinking waters was carried out in the Van province, East Turkey. Twenty-three samples of drinking water were collected in the Van province and analysed for total α, total β and (238)U activity. The total α and total β activities were counted by using the α/β counter of the multi-detector low background system (PIC MPC-9604), and the (238)U concentrations were determined by inductively coupled plasma-mass spectrometry (Thermo Scientific Element 2). The samples were categorised according to origin: tap, spring or mineral supply. The activity concentrations for total α were found to range from 0.002 to 0.030 Bq L(-1) and for total β from 0.023 to 1.351 Bq L(-1). Uranium concentrations ranging from 0.562 to 14.710 μg L(-1) were observed in drinking waters. Following the World Health Organisation rules, all investigated waters can be used as drinking water.

Radioactivity of drinking-water in the vicinity of nuclear power plants in China based on a large-scale monitoring study

The public concern for radioactivity of drinking-water has been increasing in recent years after the rapid development of nuclear power plants, and especially after the Fukushima nuclear accident. In this study, the radioactivity of water samples collected in the vicinity of nuclear facilities from seven provinces in China was measured and an average annual equivalent effective dose derived from drinking-water ingestion was calculated. The results showed that, in winter and spring, the activities of gross α and β ranged from 0.009 Bq/L to 0.200 Bq/L and from 0.067 Bq/L to 0.320 Bq/L, respectively. While, in summer and autumn, the activities of gross α and β varied from 0.002 Bq/L to 0.175 Bq/L and from 0.060 Bq/L to 0.334 Bq/L. Our results indicated that the gross α and β activities in these measured water samples were below the WHO recommended values (0.5 Bq/L for gross α and 1.0 Bq/L for gross β) and the annual equivalent effective dose derived from drinking-water ingestion was at a safe level.

Natural radioactivity in bottled mineral and thermal spring waters of Turkey

Radiological assessment of bottled mineral waters and thermal spring waters collected from various natural sources in Turkey was carried out using gross alpha and gross beta counting techniques. For 40 samples of bottled mineral water, the mean gross alpha activity concentration was determined to be 164 mBq l(-1) (min.:7 mBq l(-1); max.: 3042 mBq l(-1)), whereas the gross beta activity concentration was found to be 555 mBq l(-1) (min.: 21 mBq l(-1); max.: 4845 mBq l(-1)). For 24 samples of thermal spring water, the mean gross alpha activity concentration was obtained to be 663 mBq l(-1) (min.: 18 mBq l(-1); max.: 3070 mBq l(-1)). The gross beta activity concentration for these samples, on the other hand, was determined to be 3314 mBq l(-1) (min.: 79 mBq l(-1); max.: 17955 mBq l(-1)). These values lead to the average annual effective doses of 313 µSv for mineral waters and 1805 µSv for thermal spa waters, which are found to be higher than those recommended for drinking waters by the World Health Organization. It should be noted, however, that one will get less dose from mineral waters since the daily consumption is much lower than 2 l that these calculations assume.