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The Ebro River Delta, in the northwestern Mediterranean basin, has an extension of 320 km2 and is mainly covered by rice fields. In the framework of the ClimaDat project, the greenhouse gases atmospheric station DEC was designed and installed in this area in 2013. The DEC station was equipped, among other tools, with a Picarro G2301 instrument and an ARMON (Atmospheric Radon Monitor) to measure both CH4 and CO2 and 222Rn concentrations, respectively. The variability of methane fluxes over this area and during the distinct phases of the rice production cycle was evaluated in this study using the Radon Tracer Method (RTM). The RTM was carried out using (i) nocturnal hourly atmospheric measurements of CH4 and 222Rn between 2013 and 2019 and (ii) FLEXPART-WRF back trajectories coupled with radon flux maps for Europe with a resolution of 0.05° × 0.05° available thanks to the project traceRadon. Prior to the calculation of methane fluxes by RTM, the FLEXPART-WRF model and the traceRadon flux maps were evaluated by modelling atmospheric radon concentrations at the DEC station and comparing them with observed data. RTM-based methane fluxes show a strong seasonality with maximums in October (13.9 mg CH4 m−2 h−1), corresponding with the period of harvest and straw incorporation in rice crop fields, and minimums between March and June (0.2 to 0.6 mg CH4 m−2 h−1). The total estimated methane annual emission was about 262.8 kg CH4 ha−1. These fluxes were compared with fluxes directly measured with static accumulation chambers by other researchers in the same area. Results show strong agreement between both methodologies, having both a similar annual cycle and similar monthly mean absolute values.

Proglacial lakes are good natural laboratories to investigate groundwater and glacier dynamics under current climate conditions and to explore biogeochemical cycling under pristine lake status. This study conducted a series of investigations of 222Rn, stable isotopes, nutrients, and other hydrogeochemical parameters in Ximen Co Lake, a remote proglacial lake in the east of the Qinghai–Tibet Plateau (QTP). A radon mass balance model was used to quantify the lacustrine groundwater discharge (LGD) of the lake, leading to an LGD estimate of 10.3±8.2 mm d−1. Based on the three-endmember models of stable 18O and Cl−, the hydrologic partitioning of the lake is obtained, which shows that groundwater discharge only accounts for 7.0 % of the total water input. The groundwater-derived DIN and DIP loadings constitute 42.9 % and 5.5 % of the total nutrient loading to the lakes, indicating the significance of LGD in delivering disproportionate DIN into the lake. This study presents the first attempt to evaluate the LGD and hydrologic partitioning in the glacial lake by coupling radioactive and stable isotopic approaches and the findings advance the understanding of nutrient budgets in the proglacial lakes of the QTP. The study is also instructional in revealing the hydrogeochemical processes in proglacial lakes elsewhere.

In this study geogenic radon potential (GRP) mapping was carried out on the bases of field radon in soil gas concentration and soil gas permeability measurements by considering the corresponding geological formations. The spatial pattern of soil gas radon concentration, soil permeability, and GRP and the relationship between geological formations and these parameters was studied by performing detailed spatial analysis. The radon activity concentration in soil gas ranged from 0.11 to 434.5 kBq m −3 with a mean of 18.96 kBq m −3 , and a standard deviation was 55.38 kBq m −3 . The soil gas permeability ranged from 5.2×10 −14 to 5.2×10 −12 m 2 , with a mean of 5.65×10 −13 m 2 . The GRP values were computed from the 222 Rn activity concentration and soil gas permeability data. The range of GRP values was from 0.04 to 154.08. Locations on igneous granite rock geology were characterized by higher soil radon gas activity and higher GRP, making them radon-prone areas according to international standards. The other study locations fall between the low to medium risk, except for areas with high soil permeability, which are not internationally classified as radon prone. A GRP map was created displaying radon-prone areas for the study location using Kriging/Cokriging, based on in situ and predicted measured values. The GRP map assists in human health risk assessment and risk reduction since it indicates the potential of the source of radon and can serve as a vital tool for radon combat planning.

Among all radiation exposure, the second leading cause of lung cancer is Radon while smoking is the primary contributor. The identification of the source and extent of Radon contamination is paramount for the formulation and implementation of measures aimed at reducing Radon levels in indoor spaces. Given the serious health implications, numerous countries and regions have implemented stringent Radon exposure limits and regulations to safeguard public health. The present work is to study the activity of 222 Rn within a nuclear education laboratory. For the detection of gamma rays, a High-purity Germanium detector, with 34% relative efficiency and 0.6 mm carbon window was used. However, for the adsorption of Radon activity, 70 g charcoal in metal tin was employed. The spectrum was obtained using PROSPECT software and was calibrated using a 152 Eu standard source. The analysis of the spectrum was done using CANDLE. The radionuclides 214 Pb, 214 Bi, and 40 K which have gamma rays of 351keV, 609 keV, and 1460 keV, respectively are investigated. The measured activity of 222 Rn radionuclide was found to be ranging between 9.77±0.73 Bq/Kg to14.00±1.00 Bq/Kg.

This study focuses on the measurement of the concentrations of radon (222Rn) indoors and in the soil as well as their ambient dose equivalent rate in the cobalt–nickel bearing area of Lomié in the Eastern region of Cameroon. A total of 98 radon track detectors (commercially RADTRAK2®, Radonova Laboratories AB, Uppsala, Sweden) were used for indoor 222Rn measurement. A soil radon detector (MARKUS 10) and a pocket survey meter (RadEye PRD-ER, Thermo Scientific) were used for radon in soil and ambient dose equivalent rate measurements, respectively. Activity concentrations of 226Ra were measured using a high purity germanium detector (HPGe). Annual inhalation and external exposure doses, building materials characteristics, and correlations between indoor 222Rn, 222Rn, and 226Ra in soil were evaluated. Indoor radon concentrations varied from 30 to 300 Bq m−3 with the arithmetic mean of 58 Bq m−3. All values of indoor radon concentrations were above the world average value of 30 Bq m−3 given by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Radon concentrations in soil varied from 3.6 to 63.2 kBq m−3 with the arithmetic mean of 25.8 kBq m−3. Annual external effective dose varied from 0.23 to 0.72 mSv with the arithmetic mean of 0.41 mSv. These annual external effective dose values were all below the world average value of 0.9 mSv. 222Rn and 226Ra in soil were moderately correlated with R2 value of 0.69. The excess lifetime cancer risk (ELCR) varied from 1.5 to 16.7% with a mean value of 3.6%. This mean is about three times the action level of 1.3% recommended by the United States Environmental Protection Agency (USEPA).

The selection of low-radioactive construction materials is of the utmost importance for rare-event searches and thus critical to the XENONnT experiment. Results of an extensive radioassay program are reported, in which material samples have been screened with gamma-ray spectroscopy, mass spectrometry, and 222Rn emanation measurements. Furthermore, the cleanliness procedures applied to remove or mitigate surface contamination of detector materials are described. Screening results, used as inputs for a XENONnT Monte Carlo simulation, predict a reduction of materials background (∼17%) with respect to its predecessor XENON1T. Through radon emanation measurements, the expected 222Rn activity concentration in XENONnT is determined to be 4.2 (-0.7+0.5) μBq/kg, a factor three lower with respect to XENON1T. This radon concentration will be further suppressed by means of the novel radon distillation system.

Lung cancer may be caused by extended exposure to high amounts of radon gas, with the estimated yearly effective dosage from inhaling the gas being around 55% of the natural public exposure dose rate. In the present work, radon-222 (222Rn) gas measurements were carried out in soil samples at depth 40 cm for Al-Najaf city using RAD-7 detectors that produced from DURRIDGE (made in USA). Measurements were carried out from Augst 2024. The annual effective dose (Dinh) in soil due to radon gas concentrations that inhalation by the public was calculated. The results of radon concentration in thirty-five regions in Najaf city ranged 193.9±3.5 Bq/m3 to 6405± 20.0 Bq/m3. The maximum value of the annual effective dose calculated in Al-Saad District was 6.76 mSv/y. and the minimum value found in Al-Ulama District was 0.2 mSv/y. From the results, it follows that all of these radon concentrations and Dinh in soil samples are below 10 kBq/m3 and 10 mSv/y, respectively which it was considered low risk. Moreover, it was establishing a radon gas map to reference the following studies using GIS technology.

Radon is present in most groundwater hosted by geological formations rich in uranium. It is a gas that dissolves easily in water, poses a potential health risk when present in water used in homes. For this purpose, an exploring study of radon concentration in groundwater was conducted in three selected areas in Morocco (the Anti-Atlas, the High Atlas and the Bahira areas) using RAD-7 detector. The radon contents measured in the 34 groundwater samples, range from 0.36 to 577.1 Bq L − 1 , with average of 52.99 Bq L − 1 . Among them, only three samples exceed the accepted limit of 100 Bq L − 1 , established by the world health organization and the European Commission. Considering the level recommended by U.S. environmental protection agency, 67.64% of the samples measured had concentrations greater than 11.1 Bq L − 1 . These results indicate significantly higher 222 Rn concentrations in the groundwater of the Anti-Atlas compared to the High Atlas and occidental Meseta. This disparity could be attributed to the variation in lithology between these three different regions, as the granites are mainly the primary sources of radon in the region. The obtained annual effective doses show values ranging from 0 mSv y − 1 to 2.10 mSv y − 1 for the three regions, with samples in the Anti-Atlas and Bahira exceeding the safety limit of 0.1 mSv y − 1 proposed by both the WHO and the European Commission. This exploring study is important for both the environment and human health since it can provide important information for radon-related regulations and programs.

There is a large body of evidence that atomic nuclei can undergo octupole distortion and assume the shape of a pear. This phenomenon is important for measurements of electric-dipole moments of atoms, which would indicate CP violation and hence probe physics beyond the Standard Model of particle physics. Isotopes of both radon and radium have been identified as candidates for such measurements. Here, we observed the low-lying quantum states in 224 Rn and 226 Rn by accelerating beams of these radioactive nuclei. We show that radon isotopes undergo octupole vibrations but do not possess static pear-shapes in their ground states. We conclude that radon atoms provide less favourable conditions for the enhancement of a measurable atomic electric-dipole moment. Octupole deformation in nuclei is important to understand nuclear structure and electric dipole moments of heavy atoms. Here the authors measure energies of excited quantum states in radon isotopes and find that these isotopes do not provide favourable conditions in the search for CP-violation.

• Trees are sources, sinks, and conduits for gas exchange between the atmosphere and soil, and effectively link these terrestrial realms in a soil–plant–atmosphere continuum. • We demonstrated that naturally produced radon-222 (222Rn) gas has the potential to disentangle the biotic and physical processes that regulate gas transfer between soils or plants and the atmosphere in field settings where exogenous tracer applications are challenging. • Patterns in stem radon emissions across tree species, seasons, and diurnal periods suggest that plant transport of soil gases is controlled by plant hydraulics, whether by diffusion or mass flow via transpiration. • We establish for the first time that trees emit soil gases during the night when transpiration rates are negligible, suggesting that axial diffusion is an important and understudied mechanism of plant and soil gas transmission.