Average Radon Concentration Research Articles

Estimation of radon annual effective dose and excess lung cancer risk for the residents of KufrKhal, Jordan

This study aims to measure radon gas concentration, calculate the annual effective dose, and calculate excess lung cancer risk in KufrKhal-Jerash north of Jordan. Radon is a radioactive gas located everywhere and contributes more than 40% of people’s total dose from natural radiation. The Risk concerns have resulted from the increase in mortality due to lung cancer in KufrKhal. About 117 well-calibrated dosimeters were among the study area’s districts (Hill 1, Hill 2, Hill 3, and village center). Each dosimeter consists of a plastic cup with known dimensions and a piece of solid state nuclear track detector (SSNTD) type CR-39 fixed in the inner bottom of the cup. After 90 days, the retrieved detectors were chemically etched, and the track density (tracks.cm−2) was determined. The results showed that the average radon concentrations drastically varied between the districts of KufrKhal (17.1–128.8 Bqm−3). However, the mean radon values in different districts are closely related (64.4–75.5 Bq.m−3). The lowest concentration (17.1 Bqm−3) was found in the Hill 1 district, and the highest value (128.8 Bqm−3) was found in the village center. However, the overall radon concentration in KufrKhal was approximately 69.2 Bqm−3. This value is within the range of the national average level (43.2 – 77.4 Bq.m−3) and way below the national action level (200 Bq.m−3). Furthermore, the corresponding values of the annual effective dose (AED) and the excess lung cancer risk (ELCR) for dwellers in this village were calculated to be 1.8 mSv.y−1 and 0.2%, respectively. These values, according to Jordan’s national regulations are acceptable.

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.

Investigating the relationships between radon and the geology of the Sterkfontein cave

Radon, a naturally occurring radioactive gas, has become a subject of increasing interest and concern, particularly in the context of subterranean environments such as caves. This research investigates these dynamics in the Sterkfontein Cave in South Africa, which has formed in the karst geology of the Cradle of Humankind, Gauteng. Additionally, it set out to compile a radon map for the cave, identifying potential radon hotspots. Twenty-four electret ion chambers were placed in the tourist section of the cave and left for a period of 24 h. The radon concentrations were found to be between 53 Bq/m3 and 2770 Bq/m3. Three regions within the cave exhibited elevated radon concentrations, with these occurrences being linked to phosphatic deposits. A subterranean lake also concentrates radon gas in the lower areas of the cave. While the cave's average radon concentration of 427 Bq/m3 exceeds the World Health Organization's (WHO) hazardous level of 300 Bq/m3, occupational exposure remains minimal during a typical cave tour. Consequently, there is no discernible risk during an average tour through the cave.

Long-term comparison and performance study of consumer grade electronic radon integrating monitors

This study reports the performance of 7 types of consumer grade passive Electronic Radon Integrating Monitors, ERIM (AlphaE, AER Plus, Canary, Corentium Pro, Radon Scout Home, Ramon and Wave) and passive etched track radon detectors. All monitors and passive radon detectors were exposed side by side for 2 periods of 3 months under controlled conditions in the UKHSA radon chamber and in a stainless steel container to an average radon concentration of 4781 Bq m−3 and 166 Bq m−3, respectively. The performance of each individual monitor was compared with Atmos 12DPX and AlphaGUARD P30 reference instruments. The performance of the monitors was evaluated by estimating the biased, precision and measurement errors of each type. It was found that UKHSA passive radon detectors showed excellent performance (measurement error < 10%) at both higher and lower exposures. The AlphaE, Canary and Ramon showed excellent performance, with measurement error <10%, when they were exposed to radon concentrations between 4000 Bq m−3 and 6000 Bq m−3 in the UKHSA radon chamber. However, when the monitors were exposed to radon levels below the UK radon Action Level of 200 Bq m−3, the only ERIM which had a measurement error <10% was the Radon Scout Home. All other monitors showed a significant decrease in their performance with measurement errors ranging between 20% and 50%. The calibration factor, which is the ratio between the measured value (background is subtracted) and the reference value, was also studied. It was found that the calibration factors of individual monitors changed significantly. Calibration measurements in 2019 and in 2023 found that the percentage change varied between −46% and +63%. This shows the importance of initial and regular calibration, and maintenance of the monitors.

Unintended Consequences of Urban Expansion and Gold Mining: Elevated Indoor Radon Levels in Gauteng Communities’ Neighboring Gold Mine Tailings

The province of Gauteng in South Africa has a rich history of gold mining, which has driven economic growth and urbanization. Gold mining has also created over 270 gold mine tailings (GMT), now surrounded by human settlements due to a housing shortage. These GMT pose a health risk as they harbor elevated uranium, which over time undergoes radioactive decay to produce radon, a known lung carcinogen. This study aimed to investigate the potential correlation between the proximity to gold mine tailings (GMT) and indoor radon concentrations in Gauteng’s residential dwellings. Volume activity of radon (VAR) inside 330 residential dwellings was measured in residential dwellings located proximally (&lt;2 km) and distally (&gt;2 km) to gold mine tailings using AlphaE radon monitors during winter. An interviewer-administered questionnaire was utilized to obtain data on factors that may influence indoor radon activities. Descriptive statistics and bivariate logistic regression analyzed the influence of proximity to gold mine tailings and dwelling characteristics on VAR. Furthermore, VAR was compared to the World Health Organization (WHO) radon reference level of 100 Bq/m3. Residential dwellings near gold mine tailings had significantly higher average indoor radon concentrations (103.30 Bq/m3) compared to the control group (65.19 Bq/m3). Residential dwellings proximal to gold mine tailings were three times more likely to have VAR beyond the WHO reference level of 100 Bq/m3. Furthermore, they had estimated annual effective doses of 2.60 mSv/y compared to 1.64 mSv/y for the control group. This study highlighted a concerning association between proximity to gold mine tailings and elevated indoor radon levels. Public health interventions prioritizing residential dwellings near gold mine tailings are crucial. Educational campaigns and financial assistance for radon mitigation systems in high-risk dwellings are recommended. Residents near gold mine tailings are encouraged to ensure continuous natural ventilation through frequent opening of windows and doors.

Strategy and Metrological Support for Indoor Radon Measurements Using Popular Low-Cost Active Monitors with High and Low Sensitivity.

Traditionally, for indoor radon testing, predominantly passive measurements have been used, typically applying the solid-state alpha track-etch method for long-term and the charcoal method for short-term measurements. However, increasingly, affordable consumer-grade active monitors have become available in the last few years, which can generate a concentration time series of an almost arbitrary duration. Firstly, we argue that consumer-grade monitors can well be used for quality-assured indoor radon assessment and consequent reliable decisions. Secondly, we discuss the requirements of quality assurance, which actually allow for reliable decision-making. In particular, as part of a rational strategy, we discuss how to interpret measurement results from low-cost active monitors with high and low sensitivity with respect to deciding on conformity with reference levels that are the annual average concentration of indoor radon. Rigorous analysis shows that temporal variations in radon are a major component of the uncertainty in decision-making, the reliability of which is practically independent of monitor sensitivity. Manufacturers of low-cost radon monitors already provide sufficient reliability and quality of calibration for their devices, which can be used by both professional inspectors and the general public. Therefore, within the suggested measurement strategy and metrologically assured criteria, we only propose to clarify the set and values of the key metrological characteristics of radon monitors as well as to upgrade user-friendly online tools. By implementing clear metrological requirements as well as the rational measurement strategy for the reliable conformity assessment of a room (building) with radon safety requirements, we anticipate significant reductions in testing costs, increased accessibility, and enhanced quality assurance and control (QA/QC) in indoor radon measurements.

A study of 222Rn/220Rn exhalation rate and indoor 222Rn/220Rn levels in higher Himalayan terrain.

The noble radioactive gas radon and its isotope thoron dominate terrestrial radiation in the indoor environment. These gases eventually disintegrate generating radioactive ions that readily adhere to aerosol particles. This study was conducted in a tectonically active location with significant radon concentrations. The obtained average values of radon mass exhalation and thoron surface exhalation rate from this study are higher than the global average values of 56 mBq kg-1h-1 and 1000 mBq m-2s-1, respectively. As the exhalation rates are higher, naturally the average radon and thoron concentrations are also greater than the worldwide average values of 40 and 10Bqm-3, respectively. No significant correlation was observed between 222Rn and 220Rn exhalation rate and indoor 222Rn/220Rn concentration. The exposure dose due to 222Rn, 220Rn and their progenies shows no significant health risk.

Evaluation of consumer digital radon measurement devices: a comparative analysis

Kansas State University (KSU) Engineering Extension conducted an abridged evaluation of eight consumer grade digital radon monitors. Using the KSU secondary radon chamber, these devices were exposed to three different radon concentrations for 7 d in average household temperature and relative humidity conditions. The three different radon concentration ranges used were: 12.8 pCi L−1 to 15.5 pCi L−1 (473.6 Bq m−3–573.5 Bq m−3), 27.7 pCi L−1 to 29.4 pCi L−1 (1024.9–10 857.8 Bq m−3), and ambient room level average radon concentration of 0.6 pCi L−1 (22.2 Bq m−3). The American National Standards Institute/American Academy of Radon Scientists and Technologists Performance Specifications for Instrumentation Systems Designed to Measure Radon Gas in Air (ANSI/AARST MS-PC) (ANSI/AARST MS-PC 2022 Performance Specifications for Instrumentation Systems Designed to Measure Radon Gas in Air (AARST Radon Standards)) minimum performance metrics were used to evaluate the accuracy and precision of each model type for each radon concentration tested. The eight different device models performed within the 0 ± 25% requirement for the individual percent error (IPE) for radon concentrations between 27.7 pCi L−1 and 29.4 pCi L−1 (1024.9–10 857.8 Bq m−3). For radon concentrations between 12.8 pCi L−1 and 15.5 pCi L−1 (444–592 Bq m−3) seven of the eight monitors fell within the IPE requirement and for ambient room radon concentrations six of the eight monitors fell within the IPE requirement for the ANSI/AARST MS-PC minimum performance requirement (ANSI/AARST MS-PC 2022 Performance Specifications for Instrumentation Systems Designed to Measure Radon Gas in Air (AARST Radon Standards)) ranges. All eight device models fell within the ± 15% ANSI/AARST MS-PC minimum performance requirement (ANSI/AARST MS-PC 2022 Performance Specifications for Instrumentation Systems Designed to Measure Radon Gas in Air (AARST Radon Standards)) coefficient of variation (CV) range for radon concentrations between 12.8 pCi L−1 and 15.5 pCi L−1 (444–592 Bq m−3) and for radon concentrations between 27.7 pCi L−1 and 29.4 pCi L−1 (1024.9–10 857.8 Bq m−3). In the future, evaluating the performance of these models over time to observe their long term accuracy and precision is anticipated.

A Study on Geographic Correlation between Indoor Radon Exposure and Leukemia Incidence in Canada.

In Canada, leukemia is diagnosed at a rate of 15 cases per 100,000 persons and accounts for about 3% of all new primary cancers. In this study, geographical correlation between residential radon exposure and leukemia incidence was investigated at a provincial level with more accurate long-term radon measurement data in 21,330 homes and 10-y (2000-2009) age standardized incidence rates per 100,000 population for various subtypes of leukemia. The analyses showed that the incidence rate of non-Hodgkin lymphoma is statistically significantly correlated with average indoor radon (222Rn) concentration for Canadian females (p = 0.01210) but not for males. At a provincial level, the association between average indoor radon level and chronic lymphocytic leukemia incidence rate is statistically significant (p = 0.0167), and the correlation is somewhat stronger for females (p = 0.0043). No correlation was found between indoor radon exposure and any other subtypes of leukemia evaluated in this study.

Measuring the concentration of radon gas at the College of Dentistry- Al-Iraqia University using (CR-39) detector

In this study, the concentration of radon gas was measured at the College of Dentistry-Al-Iraqia University using a nuclear pathway detector (CR-39). The detector was placed at a distance of 160 cm from the ground level. The detector was exposed to alpha fragments for 30 days. The results showed that the concentration of radon gas has Changed from one site to another. It ranged from the lowest (28.418 Bq/m3) to the highest (233.491 Bq/m3), with an average radon concentration equal to (90.279 Bq/m3). All results were within the permissible limit of a scientist except for one sample A2 in the chemistry laboratory, which was higher than the international permissible limits (200-300 Bq/m3) and recorded by the International Commission on Radiological Protection Statement on Radon.

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.

Radon, Thoron and Polonium Concentrations Estimated in Building Materials Samples Collected from Al-Shatra, Dhi-Qar, Iraq

Radon, Thoron and their short-lived daughters have a high contribution to background radiation, as long-term exposure causes the risk of lung cancer. In current study, five types of building materials with a total 55 samples in Al-Shatra City, Dhi-Qar Governorate, Iraq collected to measure the radon and thoron concentration by using CR-39 solid state nuclear track detector. The results showed that the average radon concentrations in all samples were (103.53±55.94) Bqm−3, while the average thoron concentration was (53.20±44.69) Bqm−3. On the other hand, the annual effective dose of radon ranged between (0.85-6.46) msvy−1, with an average of 2.61msvy−1. While, for thoron concentration was ranged between (0.12-3.28) msvy−1, with an average of 1.49 msvy−1. The annual effective dose was found acceptable limit (3-10 msvy−1) recommended by the International Commission on Radiological Protection (ICRP). On the other side, the average Polonium concentrations (218Po, 214Po) have been found to be 2.053 KBqm−3, 0.866 KBqm−3, respectively.

Evaluation of Radon Concentration in Soil Sample from Boreholes in Kaltungo Local Government Area of Gombe State, Nigeria

The evaluation of radon concentration in soil sample from boreholes in Kaltungo local Government area of Gombe state, Nigeria have been carried out. A total of fifteen (15) soil samples were collected from different boreholes sites in five (5) different locations and were analyzed using Gamma spectrometry (Sodium Iodide with thallium NaI (TL) detector. The mean result of Radon activity concentration obtained varies from 0.86± 0.05 to 1.71± 0.03 Bqm-3 and the annual effective dose rate ranged from 0.0039 to 0.0077WLm/y respectively. The result shows variations in the radon concentration with various depths which indicates a relative dependence of radon concentration with depths. Comparing the results with the WHO recommended value of 100 Bqm-3 indicate that the mean values for all the boreholes soil samples were below the world recommended value. Also the mean values for all the boreholes soil samples were below the world average radon concentration of 40Bqm-3 (UNSCEAR). The values of AEDE obtained in various borehole soil samples were less than the ICRP world average. Therefore, the soil samples in each of the borehole may not pose any health threat to the residents.

Radon Exposure and Incident Stroke Risk in the Women's Health Initiative.

Little is known about the role of radon in the epidemiology of stroke among women. We therefore examined the association between home radon exposure and risk of stroke among middle-aged and older women in the United States. We conducted a prospective cohort study of postmenopausal women aged 50-79 years at baseline (1993-1998) in the Women's Health Initiative. We measured exposures as 2-day, indoor, lowest living-level average radon concentrations in picocuries per liter (pCi/L) as estimated in 1993 by the US Geological Survey and reviewed by the Association of American State Geologists under the Indoor Radon Abatement Act. We used Cox proportional hazards models to estimate risk of incident, neurologist-adjudicated stroke during follow-up through 2020 as a hazard ratio and 95% CI, adjusting for study design and participant demographic, social, behavioral, and clinical characteristics. Among 158,910 women without stroke at baseline (mean age 63.2 years; 83% white), 6,979 incident strokes were identified over follow-up (mean 13.4 years). Incidence rates were 333, 343, and 349 strokes per 100,000 woman-years at radon concentrations of <2, 2-4, and >4 pCi/L, respectively. Compared with women living at concentrations <2 pCi/L, those at 2-4 and >4 pCi/L had higher covariate-adjusted risks of incident stroke: hazard ratio (95% CI) 1.06 (0.99-1.13) and 1.14 (1.05-1.22). Using nonlinear spline functions to model radon, stroke risk was significantly elevated at concentrations ranging from 2 to 4 pCi/L (p = 0.0004), that is, below the United States Environmental Protection Agency Radon Action Level for mitigation (4 pCi/L). Associations were slightly stronger for ischemic (especially cardioembolic, small vessel occlusive, and large artery atherosclerotic) than hemorrhagic stroke, but otherwise robust in sensitivity analyses. Radon exposure is associated with moderately increased stroke risk among middle-aged and older women in the United States, suggesting that promulgation of a lower Radon Action Level may help reduce the domestic impact of cerebrovascular disease on public health.

Radon Exposure, Clonal Hematopoiesis, and Stroke Susceptibility in the Women's Health Initiative.

Studies suggest that clonal hematopoiesis of indeterminate potential (CHIP) may increase risk of hematologic malignancy and cardiovascular disease, including stroke. However, few studies have investigated plausible environmental risk factors for CHIP such as radon, despite the climate-related increases in and documented infrequency of testing for this common indoor air pollutant.The purpose of this study was to estimate the risk of CHIP related to radon, an established environmental mutagen. We linked geocoded addresses of 10,799 Women's Health Initiative Trans-Omics for Precision Medicine (WHI TOPMed) participants to US Environmental Protection Agency-predicted, county-level, indoor average screening radon concentrations, categorized as follows: Zone 1 (>4 pCi/L), Zone 2 (2-4 pCi/L), and Zone 3 (<2 pCi/L). We defined CHIP as the presence of one or more leukemogenic driver mutations with variant allele frequency >0.02. We identified prevalent and incident ischemic and hemorrhagic strokes; subtyped ischemic stroke using Trial of ORG 10172 in Acute Stroke Treatment (TOAST) criteria; and then estimated radon-related risk of CHIP as an odds ratio (OR) and 95% CI using multivariable-adjusted, design-weighted logistic regression stratified by age, race/ethnicity, smoking status, and stroke type/subtype. The percentages of participants with CHIP in Zones 1, 2, and 3 were 9.0%, 8.4%, and 7.7%, respectively (ptrend = 0.06). Among participants with ischemic stroke, Zones 2 and 1 were associated with higher estimated risks of CHIP relative to Zone 3: 1.39 (1.15-1.68) and 1.46 (1.15-1.87), but not among participants with hemorrhagic stroke: 0.98 (0.68-1.40) and 1.03 (0.70-1.52), or without stroke: 1.04 (0.74-1.46) and 0.95 (0.63-1.42), respectively (pinteraction = 0.03). Corresponding estimates were particularly high among TOAST-subtyped cardioembolism: 1.78 (1.30-2.47) and 1.88 (1.31-2.72), or other ischemic etiologies: 1.37 (1.06-1.78) and 1.50 (1.11-2.04), but not small vessel occlusion: 1.05 (0.74-1.49) and 1.00 (0.68-1.47), respectively (pinteraction = 0.10). Observed patterns of association among strata were insensitive to attrition weighting, ancestry adjustment, prevalent stroke exclusion, separate analysis of DNMT3A driver mutations, and substitution with 3 alternative estimates of radon exposure. The robust elevation of radon-related risk of CHIP among postmenopausal women who develop incident cardioembolic stroke is consistent with a potential role of somatic genomic mutation in this societally burdensome form of cerebrovascular disease, although the mechanism has yet to be confirmed.

Simulation of excess lifetime cancer risk due to the presence of radon in groundwater in Wamba town of Wamba local government area, Nasarawa state, Nigeria

The measurements of Radon concentration in ten groundwater (4-wells and 6-boreholes) from Wamba town of Wamba Local Government Area of Nigeria had been carried out. The annual effective dose (AED) and the Excess Lifetime Cancer Risk (ELCR) due to ingestion of the groundwater was established to ascertain the risk outcome from the samples. Radon concentration was detected using RAD7. The minimum Radon concentration was 0.146 Bql-1 while the maximum was 0.474 Bql-1 with mean average of 0.3134 Bql-1 which are within the United States Environmental Protection Agencies (USEPA) 11.1 Bq/L recommendation. Moreso, the maximum and minimum Annual Effective Dose (AEDing) was 3.5×10^(-6) and 1.10×10^(-6) Sv/yr which are also within the 0.1 mSv/yr World Health Organization (WHO) recommendation, while the maximum and minimum Excess Lifetime Cancer Risk (ELCR) was 1.44×10^(-5) and 4.50×10^(-6) respectively. Cumulative probability simulation of the Excess Lifetime Cancer Risk (ELCR) was carried out using Oracle Crystal Ball software validated by 10 and 90% percentiles. Comparison of all the results with the European Union (EU)/World Health Organization (WHO) value of 500 Bq/L recommendation revealed that all the samples analyzed have Radon concentration below the recommended limit. The average mean Radon concentration in the ten locations from Wamba Town are within the recommended levels as confirmed by the simulation results. At 10% Probability, the highest risk was found in Event center (1.26×10^(-5)) while the lowest was found in the water sample collected from Angwan dalatu (1.05×10^(-6)) while at 90% probability the highest (1.62×10^(-5)) and lowest (1.37×10^(-6)) risk was found in the same Events center and Angwan dalatu. Though there is variation in the results based on locations which means that the concentration of Radon gas depends on the geological nature of the bedrock and generally increases with the uranium concentration in the local geology. The Excess Lifetime Cancer Risk (ELCR) dose results are far lower than the UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiations) recommended maximum contamination level of 0.003875. Therefore, no indication of any likelihood of cancer incidence as a result of waterborne radon within the studied community that may demand urgent intervention from radiological point of view.

Alpha radioactivity in Iraqi market foodstuff: Assessing annual effective dose and lifetime cancer risk

In this study, integrated passive radon dosimeters with solid-state nuclear trace detectors (CR-39 and CN-85) were used to determine the annual effective dose and excess cancer risk for 25 different food samples in the Iraqi market. The dosimeters were deployed after four weeks of the required radiological equilibrium between radon and radium in the samples stored in sealed beakers. These caps were then quickly replaced with other caps equipped with detectors and stored for 70 days. After the detectors were removed from the samples, an electrochemical etching process was performed in a water bath and sodium hydroxide solution to reveal the traces of alpha particles on the detector surface. Microscopic observations were performed using an optical microscope to quantify the traces present on the detector surface. The results showed that the average radon concentrations for the CR-39 detectors ranged from 3.80 to 7.32 Bq/kg, with an average of 5.51 Bq/m3, and for the CN-85 detectors ranged from 1.23 to 4.51 Bq/kg, with an average of 2.79 Bq/kg. The radium and uranium concentrations for the CR-39 detector ranged from 0.299 to 0.577 Bq/kg, with an average of 0.434 Bq/kg, and from 3.72 to 7.17 Bq/kg, with an average of 5.40 Bq/kg. Comparing all the results between the two detectors, it was found that the values recorded with the CR-39 were approximately twice those recorded with the CN-85. It is important to note that all recorded values are within internationally permissible limits and do not pose a threat to human health.

Radon activity concentrations and radiological exposure assessment in drinking water in Prizren region – Kosovo

ABSTRACT Our aim was to highlight the activity concentrations of radon in four types of water used for drinking: bottled water, tap water, spring water and well water in the region of Kosovo (Prizren and Suhareka). Radon concentrations were measured using Alpha GUARD PQ2000 PRO. The measurements show that arithmetic means ± standard deviations of radon (Rn-222) concentration were as follows: 1.5 ± 0.4 Bq/L in bottled water, 2.8 ± 0.6 Bq/L in tap water, 10.2 ± 1.3 Bq/L in well water and 10.3 ± 1.4 Bq/L in spring water. The average radon (Rn-222) concentrations were found to be 1.5 ± 0.4 Bq/L in bottled water, 2.8 ± 0.6 Bq/L in tap water, 10.2 ± 1.3 Bq/L in well water, and 10.3 ± 1.4 Bq/L in spring water, respectively. The total annual effective dose for bottled water was AEDT: 7.9 ± 2.1 µSv per year, for well water is AEDT: 52.6 ± 6.9 µSv per year, spring water was AEDT: 52.9 ± 7.1 µSv per year and tap water is AEDT: 14.1 ± 4.0 µSv per year. Upon analysing these results, it is evident that the radon concentrations in the water sources studied fall within safe levels for drinking, reassuring the overall safety of the water in terms of radon contamination.

Radon activity and their radiological doses in drinking water of Chitradurga district, Karnataka, India.

In this investigation, radon activity concentration, inhalation and ingestion doses due to intake of radon in drinking water have been estimated in the Chitradurga district drinking water by using radon Emanometry technique. The average radon concentrations vary from 1.81±0.11 to 300.33±4.56Bql-1 with a mean value of 56.01±2.44Bql-1. Most of the radon concentration levels are within the World Health Organization (WHO) and European Union (EU) commission recommended level of 100Bql-1. About 70% of the drinking water had radon concentration level higher than the United States Environmental Protection Agency (USEPA) recommended Maximum Contamination Limit (MCL) of 11.1Bql-1. The annual ingestion dose varies from 0.38 to 63.03μSvy-1 with an average value of 11.75μSvy-1. The estimated annual ingestion dose is well within the WHO recommended reference level of 100μSvy-1.

Assessment of Indoor Radon Gas Concentration in National Open University of Nigeria: A Case Study of Calabar Study Centre

The current work deals with indoor radon (222Rn) concentrations measurements in the Calabar Study Centre of the National Open University of Nigeria using a Corentium Arthings digital radon detector meter for seven days representing a short–term average measurement of indoor radon gas concentration level. The geographical coordinates were recorded using a hand-held geographical positioning system for the sample point. Measurement were taken for seven days and the following data where obtained 83±2.19 Bq/m3,80±3.69 Bq/m3,86±5.57 Bq/m3,84±1.59 Bq/m3,82±3.59 Bq/m3,81±4.89 Bq/m3 and 85 ±5.59 Bq/m3.The average radon(222Rn) concentration level was found to be 83 ± 3.87 Bq/m3 with a geometric mean of 82 ± 3.54 Bq/m3. It was observed that the radon concentration was below the reference level of 100 Bq/m3 recommended by the World Health Organization (WHO). Although the current exposure of members of the public to natural radiation is not critical, the situation could change abruptly when other activities commenced. The excess life time cancer risk calculated for 70 years, 60 years, 50 years, 40 years and 30 years were 1.72 × 10−3,1.65× 10−3,1.39× 10−3,1.44× 10−3 and 0.69× 10−3 respectively. The calculated values of the excess life time cancer risk are all higher than the set limit of 0.029 × 10−3 by International Commission on Radiological Protection. However, there are no observed cases of lung cancer epidemic in this Centre. Therefore, it is advised to use fans and effective ventilation techniques to reduce radon levels. Identifying the regions of the country where people are most at risk from radon exposure should be the main goal of any national radon policy.&#x0D;