The research aimed to determine the spatiotemporal distribution patterns of radon activity concentrations in tap water of Yerevan city and assess radon-associated hazards using both deterministic and ...probabilistic approaches. This was accomplished by integrating one-year monitoring data of radon in water with water consumption habits among adult population clusters, which were identified through food frequency questionnaire in Yerevan.
The study findings indicated variations in radon activity levels across administrative districts. The highest average activity concentrations were detected in Davtashen (7.07 Bq/L), while the lowest average was observed in Kanaker-Zeytun (1.57 Bq/L). The overall pattern of spatiotemporal variation during monitoring period revealed higher prevalence of radon in water in the northern and western parts of the city compared to the east and south, indicating different sources of drinking water. The radon-associated hazard assessment from water, using a deterministic approach (e.g., inhalation, ingestion, radon dissolution in blood, total effective dose), revealed values below the individual dose criterion (IDC) of 0.1 mSv/y. Monte Carlo simulation revealed a probability of exceeding IDC in specific water consumption-based groups. Residents of Yerevan who drink more than 3 L water daily with the highest observed activity concentration of 11.4 Bq/L, have an 86.26 % chance of exceeding IDC. Residents consuming 2.1 L water daily have a 7.02 % chance of exceeding IDC.
The study highlights the importance of applied principles and methodologies for radon monitoring, particularly considering actual water consumption data and different risk assessment approaches. Considering the worst-case scenario results, it is recommended to keep tap water consumption up to 3 L per day, keeping the tap open longer to reduce radon levels. It also emphasizes the need for continued monitoring, given the variations in radon activity. The study provides valuable insights into radon exposure assessment, mitigation, and action plans in terms of water safety and public health.
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•The highest radon in water activity was recorded northeast of Yerevan.•Inhalation is the main pathway of internal radon exposure from tap water.•Water consumption data is crucial in radon exposure assessment through ingestion.•Probabilistic assessment indicated exceeded IDC for the highest water consumption.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The risk of human exposure to nanoplastics (NPs) is increasing due to the incomplete decomposition and accumulation of plastic debris in the environment. Dietary intake is the most common way for ...human body to ingest NPs. NPs cannot degrade in vivo and will accumulate in multiple tissues, which result in various tissue damages. Although numerous studies have focused on evaluating the influences of exposure to NPs, the exposure amounts investigated were much higher than the actual exposure level in human daily life. Therefore, it is necessary to evaluate the hazards of exposure to low-dose NPs. Intestinal flora is a generally recognized sensitive indicator for NPs exposure, so determining a safe threshold to intestinal flora can represent the maximal no-effective dose for the human body of NPs exposure. Based on these information, mice were exposed to NPs at concentrations of 0, 0.001, 0.005, 0.01 and 0.1 mg kg−1·BW, respectively. The composition changes of the intestinal flora were investigated after exposing 28 days. The obtained consequences indicated that 0.01 mg kg−1·BW was the maximal no-effective dose to intestinal flora. This study provided a clear safe threshold for investigating the potential adverse effects of low-dose NPs exposures on human health.
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•The no observable effect level of nanoplastics on intestinal flora was investigated.•The no observable effect level of nanoplastics on intestinal flora was 0.01 mg kg−1·BW.•Our investigation identified the threshold of potential adverse effects of low-dose NPs exposure.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In recent years, an increase in the collective dose from medical exposure has been recorded annually, which is associated with an increase in the availability of high-tech methods of medical care and ...an increase of their percentage in the structure of X-ray studies. However, any exposure to ionizing radiation on a patient is associated with an increased risk of stochastic effects. The justification principle is the most effective to ensure the radiation safety of patients. The article considers in detail the experiment on the application of the justification principle in medical organizations. The aim of the study was to evaluate the incidence of unjustified referrals to radiological examinations and their impact on the collective effective dose of patients in outpatient medical organizations. As a result, it was ound, that the collective dose from studies with unjustified referrals contributes 21% to the annual collective dose from X-ray studies in outpatient medical organizations. The result obtained confirms the need to ensure the availability of information on clinical recommendations, the accumulated effective dose and patient characteristics in medical information systems, and proves the importance of using this information when prescribing X-ray radiological studies.
•Estimates were made of number of patients likely receiving cumulative effective dose ≥100 mSv in 5-years from CT exams.•It results in about 2.5 million patients in 35 OECD countries.•Countries were ...classified into Low: 0 to <1, Medium: 1 to <2 and High: ≥2 patients with CED ≥ 100 mSv/1000 population.•There are 2 countries in Low, 24 in medium and 9 in high number group.•Stake holders in patient radiation safety should attend to the issue of high doses to such large number of patients.
To estimate the number of patients in OECD (Organization for Economic Co-operation and Development) countries who receive a cumulative effective dose (CED) ≥ 100 mSv from recurrent computed tomography (CT) exams.
Taking into account recently published data on the number of CTs per patient and the fraction of patients with CED ≥ 100 mSv as well as country-specific data for the number of CT exams/1,000 population from OECD publication, this paper makes estimations for 35 OECD countries.
The estimated total number of patients with CED ≥ 100 mSv for all 35 OECD countries combined in a 5-year period is around 2.5 million (2,493,685) in a population of 1.2 billion (1,176,641,900), i.e., 0.21% of the population. Expressed per 1,000 population, the range is from 0.51 for Finland to 2.94 for the US, a nearly six-fold difference. Countries with more than 2 patients with CED ≥ 100 mSv in a 5-yr period per 1,000 population are: Belgium, France, Iceland, Japan, Korea, Luxembourg, Portugal, Turkey, and US.
The first estimates of the number of patients likely receiving CED ≥ 100 mSv through recurrent CT exams in 35 OECD countries indicate that 2.5 million patients reach this level in a 5-year period. There is an urgent need for various stakeholders including medical physicists, referring physicians, health policy makers, manufacturers of CT equipment and epidemiologists to attend to the issue in the interest of patient radiation safety.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The activity concentrations of 226Ra, 232Th, and 40K from 102 building materials samples were determined using a high-purity germanium (HPGe) detector. The activity concentrations were evaluated for ...possible radiological hazards to the human health. The excess lifetime cancer risks (ELCR) were also estimated, and the average values were recorded as 0.42 ± 0.24 × 10−3, 3.22 ± 1.83 × 10−3, and 3.65 ± 1.85 × 10−3 for outdoor, indoor, and total ELCR respectively. The activity concentrations were further subjected to RESRAD-BUILD computer code to evaluate the long-term radiation exposure to a dweller. The indoor doses were assessed from zero up to 70 years. The simulation results were 92 ± 59, 689 ± 566, and 782 ± 569 μSv y−1 for indoor external, internal, and total effective dose equivalent (TEDE) respectively. The results reported were all below the recommended maximum values. Therefore, the radiological hazards attributed to building materials under study are negligible. Keywords: Annual effective dose, Excess lifetime cancer risk, External dose, Internal dose, Total effective dose equivalent
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study evaluates the radiological risk associated with the consumption of infant powdered milk in Albania. Infant powdered milk is the basic foodstuff for their growth and development in many ...countries around the world. The activity concentration of radionuclides (40K, 226Ra, 232Th and 137Cs) was measured in fourteen types by using the gamma-ray technique. The results indicated that the activity concentration of 40K, 226Ra and 232Th were detected in all selected samples, whereas 137Cs were not detected in most of them. The activity concentration of 40K, 226Ra and 232Th varies from 92.83 ± 4.32 to 400.53 ± 17.00 Bq kg−1, 0.80 ± 0.15 to 4.91 ± 0.28 Bq kg−1 and 0.19 ± 0.02 to 1.89 ± 0.14 Bq kg−1, respectively. The highest value for 137Cs was found to be 0.36 ± 0.03 Bq kg−1. The average values of Annual Effective Dose (AED) due to consumption of powdered milk were found to be 664.54 ± 31.11 μSv y−1 for infants ≤1 year and 138.53 ± 5.40 μSv y−1 for infants 1–2 years. The values of dose in this study were lower than the recommended limit of 1 mSv y−1 set by WHO/FAO and ICRP for all ages. Therefore, brands of powdered milk are safe, so, these can be normally consumed by infants in Albania.
•Radiological risk associated with the consumption of infant powdered milk.•Activity concentration of natural and artificial radionuclides in powdered milk was calculated.•The annual effective dose intake by infants ≤1 year and 1–2 years, due to the ingestion of radionuclides was estimated.•The brands of powdered milk have acceptable radiological risk.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The objective of our study was to compare dose-length product (DLP)-based estimates of effective dose with organ dose-based calculations using tissue-weighting factors from publication 103 of the ...International Commission on Radiological Protection (ICRP) or dual-energy CT protocols.
Using scanner- and energy-dependent organ dose coefficients, we calculated effective doses for CT examinations of the head, chest, coronary arteries, liver, and abdomen and pelvis using routine clinical single- or dual-energy protocols and tissue-weighting factors published in 1991 in ICRP publication 60 and in 2007 in ICRP publication 103. Effective doses were also generated from the respective DLPs using published conversion coefficients that depend only on body region. For each examination type, the same volume CT dose index was used for single- and dual-energy scans.
Effective doses calculated for CT examinations using organ dose estimates and ICRP 103 tissue-weighting factors differed relative to ICRP 60 values by -39% (-0.5 mSv, head), 14% (1 mSv, chest), 36% (4 mSv, coronary artery), 4% (0.6 mSv, liver), and -7% (-1 mSv, abdomen and pelvis). DLP-based estimates of effective dose, which were derived using ICRP 60-based conversion coefficients, were less than organ dose-based estimates for ICRP 60 by 4% (head), 23% (chest), 37% (coronary artery), 12% (liver), and 19% (abdomen and pelvis) and for ICRP 103 by -34% (head), 37% (chest), 74% (coronary artery), 16% (liver), and 12% (abdomen and pelvis). All results were energy independent.
These differences in estimates of effective dose suggest the need to reassess DLP to E conversion coefficients when adopting ICRP 103, particularly for scans over the breast. For the evaluated scanner, DLP to E conversion coefficients were energy independent, but ICRP 60-based conversion coefficients underestimated effective dose relative to organ dose-based calculations.
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