High Radon Concentrations Research Articles

Assessing carcinogenic radon levels in water from Er-Rachidia, Morocco using LR-115 nuclear track detectors

Abstract The current study investigates the presence 222Rn in tap water, natural spring water, and well water from various locations in Er-Rachidia, Morocco, to assess the potential radiological risks posed to the local community. Radon, a radioactive gas produced by the decay of uranium and thorium in rocks and soil, poses significant radiation hazards. Using a Nuclear Track Detector (LR-115), researchers investigated the presence of radon in water from wells, dams, and rivers. The highest radon concentrations are found in well water, with an average of 1.92 Bq/L. The concentration of river water is the lowest, coming in at 0.53 Bq/L, while the average concentration of dam water is 0.84 Bq/L. On average, the annual effective dosage for well water is 4.57 ms per year. The water dosages from dams range from 1.74 to 2.44 μSv/y, with 1.98 being the average. River water ranges from 0.51 to 1.69 mSv/y, averaging 1.24 µSv/y. The excess lifetime cancer risk varies significantly across water sources: 1.27 × 10−3 to 1.84 × 10−3 (average 1.60 × 10−3) for well water, 0.61 × 10−3 to 0.85 × 10−3 (average 0.69 × 10−3) for dam water, and 0.18 × 10−3 to 0.59 × 10−3 (average 0.43 × 10−3) for river water. The results dispel fears of significant radioactive dangers to the locals by suggesting that the measured radon concentrations are within the limits set by international organizations.

Analysis of Outdoor and Indoor Radon Concentration Time Series Recorded with RadonEye Monitors

Consumer-grade economical radon monitors are becoming increasingly popular in private and institutional use, in the contexts of both Citizen Science and traditional research. Although originally designed for screening indoor radon levels in view of radon regulation and decisions about mitigation or remediation—motivated by the health hazard posed by high radon concentrations—researchers are increasingly exploring their potential in some environmental studies. For long time, radon has been used as a tracer for investigating atmospheric transport processes. This paper focuses on RadonEye, currently the most sensitive among low-cost monitors available on the market, and specifically, its potential use for monitoring very low radon concentrations. It has two objectives: firstly, discussing issues of statistics of low count rates, and secondly, analyzing radon concentration time series acquired with RadonEyes outdoors and in low-radon indoor spaces. Regarding the first objective, among other things, the inference radon concentration reported to expected true is discussed. The second objective includes the application of autoregressive methods and fractal statistics to time series analysis. The overall result is that radon dynamics can be well captured using this “low-tech” approach. Statistical results are plausible; however, few results are available in the literature for comparison, particularly concerning fractal methods. The paper may therefore be seen as an incentive for further research in this direction.

Characteristics of radon transport and optimization of ventilation parameters in large-scale underground cavern

Radon penetrates into the underground caverns through the pores/fissures of the surrounding rock, resulting in high radon concentration area and endangering the health of construction personnel. The on-site monitoring of radon concentration in the underground powerhouse of Tuoba Hydropower Station is conducted in order to study the radon concentration level. The radon transport during the construction period of underground powerhouse under forced ventilation is established by Computational Fluid Dynamics (CFD) numerical simulation method. Furthermore, the distribution characteristics and long-term evolution law of radon concentration in underground powerhouse are revealed, and reasonable ventilation optimization measures are put forward and the results show that: (1) Blasting promotes the increase of radon concentration, while forced ventilation accelerates radon transport. (2) The airflow field along the axis is divided into a vortex distribution zone, a vortex influence zone and stable regions. (3) The radon transport includes both migration and diffusion processes based on forced ventilation. (4) The radon concentration decreases with the increase of height, while exhibits low concentration in the middle and high concentration on both sides at the same height. (5) Compared with forced ventilation, the combined ventilation can improve the ventilation efficiency and shorten the radon transport time. The research results can provide a scientific basis for the safety analysis and evaluation of deep engineering environment.

Investigation aspects of the geogenic radon potential on Bulgarian territory

Radon (222Rn) is a radioactive gas formed as a result of the radioactive decay of radium (226Ra). Radon is identified as one of the dominant sources of population exposure that could lead to lung cancer, accounting for between 3% and 14% of all lung cancers. Rocks in the Earth’s crust are a primary source of radon in the atmosphere. In this context, the geogenic radon potential (GRP) of a terrain refers to the probability of high radon concentrations being present in a building. The radon index is a concept used to characterize the geogenic potential of the terrain, providing the likelihood of radon concentration in a building, which is directly related to the influence of the Earth's surface. One approach to quantifying the radon index is based on multivariate cross-tabulation, involving two parameters: radon concentration in soil gas and the gas permeability of the earth layer, both measured at 80 cm below the surface. In Bulgaria, focused investigations on the connection between radon gas and geology, resp. on GRP have begun in the last five. As a result of the accumulated experience from field studies conducted so far related to the characterization of GRP, two important aspects have been identified that impact field measurements and the determination of radon gas in the soil, thus the methodology for calculating the radon index. The first aspect is connected with the theoretical and model-based investigations about possible state of soil saturation. The second aspect is about the GRP and fault systems in Sofia. This article makes an attempt to summarize all the studies concerning these two aspects and to suggest some further steps in the geogenic radon potential studies.

Coherent long-term average indoor radon concentration estimates obtained by electronic and solid state nuclear track detectors

Despite the rapid development of consumer-grade electronic radon monitors, their capabilities to assess long-term average radon concentrations are not systematically investigated. We present the results of a year-long measurement campaign in 32 dwellings and workplaces in two areas with typical and high radon concentrations in Bulgaria. A systematic comparison was made between electronic monitors and the gold standard — solid-state nuclear track detectors (SSNTDs). RadonEye Plus2 (RE) monitors were used, calibrated and metrologically tested at the three participating laboratories. Two SSNTD-based detectors were utilized: passive radon detectors (PRDs) developed by UKHSA, and CDs/DVDs, developed at SU. Two PRDs for quarterly radon measurements, a RE, a CD and a DVD were placed at each location. Additional old CDs/DVDs were collected for retrospective radon estimates. The results for the annual average radon concentrations, estimated by the four methods are presented. The average difference between the REs and PRDs estimate was 8% (median 4%), between the REs and CDs was 5% (median 0.4%) and between REs and DVDs was −10% (median −12%). The Z-score, representing the difference normalized to its uncertainty, in most cases fell within −1 and 1, indicating excellent agreement. The retrospective estimates also demonstrated excellent agreement with the other data. However, in some cases, small but statistically significant biases were identified between REs and SSNTDs or between different SSNTDs, requiring an inclusion of a reference instrument in future studies. Overall, the results imply that with sound metrological assurance, RadonEye Plus2 monitors can assess long-term average radon concentrations with sufficient accuracy.

Characteristic parameters and radon exhalation rates of aerated concrete blocks

ObjectiveTo understand the characteristic parameters and radon exhalation rates of aerated concrete blocks. MethodsA total of 39 nationally inspected samples were measured. Their dry density was determined based on their mass and volumes, their porosities were measured on the principle of volumetric expansion, and their radium content was determined using a high-purity germanium (HPGe) detector for gamma-ray spectroscopy. Furthermore, their diffusion lengths were quantified by establishing a combined cumulative and diffusion chamber, and their radon exhalation rates were measured through closed-box testing using a continuous radon monitor. ResultsThe aerated concrete blocks exhibited dry densities ranging from 464 to 840 ​kg/m3 [average: (654.0 ​± ​82.5) kg/m3], open porosities from 67.1 ​% to 81.1 % [average: (74.3 ​± ​3.3) %, radium (226Ra) content from 12.3 to 136 Bq/kg [average: (63.0 ​± ​30.4) Bq/kg], diffusion lengths from 0.49 to 1.01 ​m [average: (0.70 ​± ​0.15) m], and radon exhalation rates from 0.6 to 22.8 Bq·m−2·h−1 [average: (7.3 ​± ​5.3) Bq·m−2·h−1]. ConclusionAerated concrete blocks exhibit significantly higher porosities, diffusion lengths, and radon exhalation rates than traditional concrete and clay bricks. These blocks might contribute to the high indoor radon concentration observed in modern buildings in China.

Assessment of the residential radon concentrations in the Bakony Region, Hungary

ObjectiveTo investigate the current levels of indoor radon activity in the geologically complex Bakony Region of Hungary, which has been historically affected by industrial activities, and to identify areas that may require further monitoring and intervention. MethodsExperiments were carried out to measure quarterly indoor radon activity concentrations in ground-floor dwellings for a year using CR-39-type nuclear track detectors at 30 locations in 9 settlements to provide current information on the Bakony Region and identify areas requiring further attention. ResultsSince the annual average indoor radon activity concentration in the Bakony Region was 86 Bq/m3 and the maximum 274 Bq/m3, that is, less than the 300 Bq/m3 national and EU reference levels, it is considered safe. Two locations were equal to or exceeded the reference level during part of the year. While most of the Region exhibited high radon concentrations in the autumn and winter, two settlements presented inverse seasonal variations. ConclusionAlthough the autumn and winter values yielded a strong correlation with the annual mean and each other, this was not the case regarding the summer and spring values. The annual mean effective dose for the Region from the inhalation of radon and its progenies was estimated to be 2.2 ​mSv/year.

Analysis of radon mitigation methods: 10-year review

Exposure to the radon gas within a building can result in an increased risk of lung cancer. To minimise the health risk, indoor radon concentrations can be reduced using well-established mitigation methods. The performance of various radon reduction methods, their combination as well as other factors that can impact the efficiency of radon mitigation, were analysed using data collected from approximately 2800 dwellings that had installed radon mitigation techniques during the period 2007–2017. As demonstrated previously (Hodgson 2011), active methods are the most effective at reducing high concentrations of radon to below the Action and Target Levels (200 Bq m−3 and 100 Bq m−3 respectively). Reduction factors of up to 5.5 using single active methods and 8.3 using a combination of active methods were estimated in this study. For indoor radon levels greater than 1 000 Bq m−3, the Active Sump remained the most efficient technique, with the Active Underfloor Ventilation being the second most effective method. Passive methods alone or in combination with other passive methods offered moderate reductions at high radon concentration. Of the passive methods, Underfloor Ventilation was found to have the highest performance with a reduction factor of 1.8. The conclusions of this study should be used to update guidance for stakeholders including householders, contractors, radon awareness campaigns and the UKradon.org website.

Radon concentration and affecting environmental conditions in water-curtain heated cultivation facilities

Farmers cultivate plants in the winter using water curtain cultivation (WCC) facilities by spraying groundwater to keep them warm. In this study, the WCC facilities exhibited high radon concentrations during winter. The risk varied significantly depending on the facility operation, peaking in the early morning and then decreasing upon ventilation. At all measurement sites, radon concentrations were low when groundwater was not used. Even during the period of facility groundwater use, if water vapor condensation does not occur, there is no significant difference from soil-only emissions. However, once water vapor condensation occurs, radon accumulates rapidly, depending on the degree of radon contamination in the groundwater. Because groundwater contamination varies according to dilution by regional rainfall or inflow from other regions due to groundwater movement, abnormal changes in radon content occur. We found that in the absence of water vapor condensation in the facility, all the radon emitted from the soil and groundwater quickly escaped to the atmosphere, resulting in significantly lower indoor radon concentrations. These findings pave the way for the development of new methods to mitigate radon in WCC facilities.

Relevance of radon progeny measurements for the assessment of inhalation doses in groundwater utilities

The high radon concentrations measured in the indoor air of groundwater facilities and the prevalence of the problem have been known for several years. Unlike in other workplaces, in groundwater plants, radon is released into the air from the water treatment processes. During the measurements of this study, the average radon concentrations varied from 500 to 8800 Bq m–3. In addition, the indoor air of the treatment plants is filtered and there are no significant internal aerosol sources. However, only a few published studies on groundwater plants have investigated the properties of the radon progeny aerosol, such as the equilibrium factor (F) or the size distribution of the aerosol, which are important for assessing the dose received by workers. Moreover, the International Commission on Radiological Protection has not provided generic aerosol parameter values for dose assessment in groundwater treatment facilities. In this study, radon and radon progeny measurements were carried out at three groundwater plants. The results indicate surprisingly high unattached fractions (fp = 0.27–0.58), suggesting a low aerosol concentration in indoor air. The corresponding F values were 0.09–0.42, well below those measured in previous studies. Based on a comparison of the effective dose rate calculations, either the determination of the fp or, with certain limitations, the measurement of radon is recommended. Dose rate calculation based on the potential alpha energy concentration alone proved unreliable.

Theoretical Prediction of the 210 Pb Burden in the Skeleton from Radon Exposure and Other Intake Routes.

The 210 Pb burden in the skeleton is a measurement value suitable for the estimation of the cumulative exposure to radon, based on which the resultant risk of lung cancer can be derived. There have been a handful of studies that successfully measured 210 Pb activity in the bones of volunteers who had chronic exposure to high concentrations of radon occupationally or in their residences. However, the quantitative relationship between measured 210 Pb activity and radon exposure remains elusive. Herein, we investigate the origin of the skeletal burden by employing the biokinetic model recommended by the International Commission on Radiological Protection and modeling various routes of intake. First, the baseline 210 Pb burden for the general public regarding eating assorted foodstuffs and breathing normal air is obtained. It is found that this baseline burden ranges between 7.3 to 46.5 Bq for a 50-y-old (male) person, which characterizes a large variance due to the uncertainty of each route of intake. Next, we concentrate on radon exposure by referring to two experimental studies where the accounts of exposure and the measured 210 Pb burden for each volunteer are documented in detail. From comparing our prediction and measurements, it is found that exposure to higher concentration of radon is the most significant source of 210 Pb intake, and the quantitative differences can be reasonably explained by the uncertainty resulting from regular intake routes. This study establishes the theoretical foundation for assessing one's risk of lung cancer due to radon exposure by measuring the 210 Pb burden in bones.

Abstract 852: Measuring the level of knowledge and awareness about radon in Northeast Tennessee

Abstract Introduction: Radon, a radioactive gas found in soil and rocks, is the second leading cause of lung cancer in the United States (1). Despite its significant health risks, radon awareness and knowledge remain low (2). In Tennessee, where geological factors contribute to elevated radon levels, understanding the levels of awareness and knowledge about radon is crucial (3). This study focuses on Northeast Tennessee, an area known for its high radon concentrations. Methods: This cross-sectional study, conducted from September to November 2023, aims to assess radon awareness and knowledge among participants from seven Northeast Tennessee health councils. These councils play a critical role in public health initiatives and provide access to individuals actively involved in health-related discussions. A convenience sample of 150 participants was chosen from an email listserv of 650 health council members. Participants, aged 18 or older, affiliated with the health councils in the study area, and physically present in the US, were eligible to participate. Demographic data, radon knowledge and awareness were assessed. Additional questions evaluated information sources, concern levels, and willingness to inform the community about radon. Conclusion: This research addresses a significant knowledge gap regarding radon awareness and knowledge in Northeast Tennessee, an area with unique geological factors that elevate radon exposure risks. The study's findings will contribute to the development of targeted educational campaigns and interventions, ultimately promoting awareness and proactive measures to mitigate radon exposure in the region. With the potential to inform policy and public health efforts, this study holds the promise of reducing the health risks associated with radon in Northeast Tennessee. Citation Format: Kawther Al ksir, Stacy Stanifer, Megan Quinn, Hadii Mamudu, Deborah Slawson. Measuring the level of knowledge and awareness about radon in Northeast Tennessee [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 852.

Measurement and characteristics of radon flow in an extremely arid region based on a closed-system earth-air model

Radon (222Rn) is a radioactive gas that occurs naturally in the soil and is harmful to the environment and health. However, the measuring the amount of radon flowing is challenging. This study reveals the mechanism responsible for radon transportation and concentration variation, the main driving forces acting, and the key factors operating in the vadose zone. In this study, two separate holes were used to monitor the amount of earth-air and radon flowing in and out of the soil in the extremely arid region in China where the Mogao Grottoes are located. Using a closed-system model, the quantity, characteristics, and regularity of the flow of earth-air and radon were thus determined on daily and yearly timescales. The same patterns of variation in earth-air flow and radon concentration were found at the two sites, both depending on the variation in the atmospheric pressure (AP). When the AP decreases, earth-air flows out from the soil with a high radon concentration. Conversely, when the AP increases, earth-air enters into the soil with a low radon concentration. Thus, radon is continuously emitted from the soil. The concentration of radon in the earth-air is proportional to the rate of flow of earth-air and therefore increases as the AP decreases. The radon emission also varies with the seasonal variation in temperature and AP, which is high in summer and low in winter. On a daily timescale, the radon varies in a bimodal manner. Therefore, the net amount of radon emitted from the soil is positively correlated with the amplitude of the AP fluctuation, temperature, soil porosity, and thickness of the vadose zone. The atmospheric pumping is the main driving force responsible for the radon emission. However, the surface closure, landform, cracks, faults, grain size, pore structure, soil adsorption, basal uranium/radium, salts, wind, lunar cycle, latitude and altitude have important effects on the number of radon emission. As such, it provides a scientific basis for the effective utilization of radon and prevention of its emission from soil.

Investigating and Measuring Radon Gas Concentration in Tehran and Alborz Metro Stations

Abstract Humans are regularly exposed to various types of radioactive radiation and, of course, to Radon-222 over the course of their lives. According to the report of the United Nations scientific committee on the effects of atomic radiation in 2000, the average human is estimated to be exposed to about 4.2 mSv of radioactive radiation each year, 52% of which is caused by inhalation of radon gas. The radon gas is one of the most important elements that is emitted from the decay of natural uranium and radium in the earth. Therefore, the concentration of this gas can be higher in enclosed spaces, especially underground locations, and it is important to measure the amount of radon gas radiation in these underground stations. In this research, a domestically manufactured environmental meter for radon gas was used to measure the concentration of this gas in different Tehran metro stations. In general, all 42 subway stations of Tehran and Karaj cities were measured at continuous time intervals during the spring season. On average, trace amounts of radon gas were observed in all the stations, but high concentrations of radon gas were measured at some stations, such as Tajrish and Ghaem stations in the northern Tehran-Karaj plain due to underground water resources, fault type and distinct geological structures. According to the US Environmental Protection Agency (EPA) standard, the maximum permissible amount of radon gas concentration in the air is 148 Bq/m3, while the average amount was 156 Bq/m3 at Tajrish station. This amount is above the permissible limit and can therefore be considered hazardous to health. Geologically, the Meydan-e-Azadi (Azadi square) station on line 4 located in the center of Tehran also revealed a near high radon concentration due to bedrock that it mainly has been consisted of calcite. Consequently, measures for better ventilation and easier air movement are required in such stations.

Performance evaluation of radon active sensors and passive dosimeters at low and high radon concentrations

Radon is a naturally occurring radioactive gas that has the potential to accumulate in buildings and over time, causes lung cancer in humans. Present methods for radon measurements are disparate, which pose challenges to benchmark radon concentrations and to accurately assess the population's received dose. This paper presents a comprehensive performance evaluation of radon dosimeters and three grades of active radon sensors: consumer-, medium- and research-grade. The measurements were performed at relatively low (300 Bq/m3) and high (2′000–3′000 Bq/m3) radon levels. Tests were conducted in an atomic shelter, with stable temperature and humidity conditions. The active sensors differed in absolute accuracy and dynamic performance (time-dependent correlations) according to their grade. Research-grade sensors performed marginally better than medium-grade sensors, and significantly better than consumer-grade sensors. Relative to the reference, the error (percentage difference between the reference and the sensors) was below 5 % for research- and medium-grade sensors, and nearly 10 % for consumer-grade sensors at high radon levels. Performance of sensors diminished at low radon levels, except for research-grade sensors. Passive dosimeters generally performed better at high radon levels than at low ones. Their longer exposure time was associated with increased measurement reliability. These results highlight the need for understanding the purpose of measurements in order to select an adequate radon detector, and ultimately, reduce measurement and interpretation errors. This study raises awareness among researchers, radon professionals and the general public regarding the performances of different active radon sensors and passive dosimeters. It also sheds light on their respective scope of application.

Adsorption’s regularities of radionuclides on adsorbents from solutions

The object of research: The object of research is the uranium isotopes were found in the soil of the locations of numerous thermal and cold springs in the Kalbajar region of Azerbaijan in the same proportions as in natural uranium deposits.
 Investigated problem: Uranium isotopes were transferred from soil samples to solutions. İnvestigated problem of scientific work is study of regularities of adsorption of uranium isotopes from solutions on the surfaces of various adsorbents.
 The main scientific results: It is defined high adsorption properties of DOWEX HCR granular elastomer, activated carbon and expanded clay on the result of researches. The activation’s energy of desorption of uranium isotopes from the surface of adsorbents were determined. Relatively low values (22.1–26.3 kJ/mol) of the activation’s energy of desorption of uranium isotopes from the surface of adsorbents indicate the absence of the chemical nature of sorption and the presence of only weak van der Waals forces between the absorbed isotopes and the surface of the adsorbents.
 The area of practical use of the research results: The regularities of adsorption of uran isotopes on adsorbent masses from aqueous solutions can be used as an original cleaning method of the drain water of the physical stage of crude oil refining or other radiochemical processes to the norms for waste water.
 Innovative technological product: It was determined based on the research, that the concentration of radon in the waters of most springs of the “Istisu” deposit is below the regulatory permissible value (60 Bq/l), which indicates the suitability of these spring waters for use in medical treatment procedures.
 Scope of the innovative technological product: It is planned to resume (prevented more than 40 years ago due to global regional problems) the production of the original trademark – “Istisu” medicinal water, with the concentration of radon below the standard value. Considering the two-fold decrease in radon concentration in water over four days, the waters of the individual sources examined, with a 100-fold high radon content, after a certain time (several months) can also be used for use in medical procedures, which allows their transportation to large distances

A Review on Measurement of Radon Gas Concentration in Drinking Water

Radon is a noble gas that has a high risk to the human body, and existence at various rates in soil, air and different source of water. Moreover, radon has a short lifetime but it can produce more risk to public health. Humans are good users of water by food, drinking water, vegetable, shower and dishwashing, however, we do have not good knowledge about the risk of radon, and we need to do more research because it’s one of the main factors to various types of cancer such as lung and stomach cancer. This review used different data in some research in different countries (Romania, Chania, Brazil, Sudan, India, Syria, Iraq, and Yemen) in (2012-2020) with the help of the RAD7 detector because it has higher resolution and is faster in measurement. In current review, higher average reading of radon was found in Nigeria, its reading was (36.1 Bq/L) which was more than the standard value in the world for drinking water (11.1 Bq/L). In any country there are so many factors to high and low concentration of radon in drinking water which are discussed and explained in this review.

Radon concentration in spring water as an indicator of seismic activity: a case study of the Muzaffarabad Fault in Pakistan.

Radon and its progenies found in water indicate the existence of seismically active faults in the region. However, exposure to high levels of radon can also result in radiation-related health risks. This study focuses on radon-based active tectonic studies along the Muzaffarabad Fault in the core of the Hazara-Kashmir Syntaxis (HKS), NW Himalayas, Pakistan. In this study, spring water samples were collected along roadside of Jhelum Valley and in close proximity to the Muzaffarabad Fault in Pakistan using Radon Thoron Monitor (RTM1688-2). The results of the study showed that the radon concentrations in the water samples ranged from 1.895 to 17.097 Bq/l. The study found that the highest radon concentration was observed in the samples collected closest to the fault, while the lowest concentration was observed in the samples collected further away. The statistical analysis between the radon concentration and the distance from the fault showed a strong inverse relationship (R2=0.73). The study also found that 68% of the sampling sites had radon concentrations that exceeded the maximum contamination level (MCL) set by the US Environmental Protection Agency (EPA). The higher radon concentrations in the springs water suggest the probability of earthquake, which in turn poses potential health risks for the local population. The findings suggest that the measurement of radon concentration in water can be used as a tool for identifying seismically active faults in the region.

High radon levels and adverse environmental conditions in using RAD7.

Good response was observed in simultaneously using six RAD7 detectors at high radon concentrations, temperatures and relative humidity conditions. RAD7 detectors were tested in laboratory using radon chambers from 13 up to 59.8kBqm-3, statistical analysis allows to distinct between counting errors and radon variation. RAD7 detectors were exposure to extreme environmental conditions at uranium flat mine. High radon concentration in soil from a confined uranium mineral was 274.3kBqm-3 at 44°C temperature and 20% relative humidity. Inside uranium mine radon increased from 1.0 up to 88.5kBqm-3.

Immune status of people living in the Tande-Tande sub-village (Indonesia), an area with high indoor radon concentration.

On Earth, there are significant variations in terms of exposure to naturally occurring radiation among different areas. Radon, a naturally-occurring radioactive gas that is the primary cause of lung cancer in nonsmokers and the second most prevalent cause among smokers, poses a considerable risk. Indoor radon, in particular, constitutes the most substantial source of natural radiation to which individuals are exposed. This study assessed the immune status of a population chronically exposed to high indoor radon concentration in Indonesia. Fifty-seven subjects from the Tande-Tande sub-village (high indoor radon concentration area) were compared to fifty-three participants living in the Topoyo village (low concentration area). We contrasted the immunological conditions of these two populations by measuring levels of tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-4 (IL-4), and IL-10 in serum. Moreover, we also measured levels of the nuclear factor kappa B (NF-κB), superoxide dismutase (SOD), glutathione peroxidase (GPX), and protein kinase B in its phosphorylated (pAkt) and non-phosphorylated form (Akt) in peripheral blood mononuclear cells (PBMCs) of a subset of participants (31 from each population). TNF-α, IFN-γ, and IL-4 levels in Tande-Tande sub-village inhabitants were significantly lower than those in the control group living in the Topoyo village (p = 0.001, p = 0.017, and p = 0.002). The concentration of IL-10 also tended to be lower in people living in the high indoor radon concentration area, but it did not differ significantly between Tande-Tande sub-village inhabitants and Topoyo inhabitants (p = 0.106). Protein levels of NF-κB, pAkt, and Akt in Tande-Tande sub-village inhabitants also did not differ significantly between Tande-Tande sub-village inhabitants and Topoyo inhabitants (p = 0.234, p = 0.210, and p = 0.657). Similarly, activities of SOD and GPX did not differ significantly between the two populations (p = 0.569 and p = 0.949). Overall, despite their chronic exposure to high indoor radon concentrations, our study revealed no increase in the levels of TNF-α, IFN-γ, IL-10, IL-4, SOD, and GPX in the inhabitants of Tande-Tande sub-village compared with people living in the Topoyo village. Furthermore, our study demonstrated no activation in the Akt pathway, as indicated by the pAkt/Akt ratio observed in PBMC lysates of individuals residing in the Tande-Tande sub-village.