Radon activity concentrations in Jale and Mersaid warm water springs in Koya District, Kurdistan Region-Iraq

Integrated environmental and health assessment from hydrogeochemistry and radiogeology parameters of hydrothermal spring attractions in Southern Thailand

The present study aimed to investigate the hydrogeochemical patterns and contamination of the radiogeology, especially radon activity, related to geothermal aquifer properties and to perform a risk assessment of annual effective doses covering all hydrothermal spring attractions in Southern Thailand. Radon is an established lung carcinogen; especially longer term exposure to radioactive radon through inhalation could be a cause of lung cancer risk. Altogether 22 hydrothermal spring samples were collected from the six hydrothermal provinces in Southern Thailand in early November of 2023. Geochemical data represented by calcium chloride and sodium chloride type, most of which were influenced by seawater intrusion. In addition, the hydrothermal springs that located along local fault zones were mainly controlled by water‒rock interactions, indicating that hydrothermal spring quality was influenced by weathering. Hydrothermal springs located along the coastlines of the Gulf of Thailand and Andaman Sea were dominated by evaporation. Radon activity concentrations show value levels from 9 Bq/L (PG1) to 7,070 Bq/L (SR3), with an average of 580 Bq/L. Radon levels of hydrothermal spring attractions can be divided into three categories: (a) low radon levels below 100 Bq/L, (b) moderate to high radon levels between 100 and 580 Bq/L, and (c) very high radon levels greater than 580 Bq/L. The total annual effective doses for adults due to ingestion and dominantly inhalation of radon at hydrothermal spring attractions varied from 0.01 to 19.30 mSv/year. These results highlight the usefulness of this method as an essential tool for delineating radon concentrations, which could be used to introduce guidelines for health risk assessment.

Spatial distribution of radon contamination in hot springs water and its cancer and non-cancer risks in the Hunza-Nagar valley, Pakistan

Radon (222Rn) is a ubiquitous radioactive gas and could threaten human life due to its potential for cancer and non-cancer risks. This study examined the measurement of 222Rn concentration and associated health risks in the hot springs of Hunza-Nagar valley. For this purpose, the hot springs water of Hunza and Nagar districts and the background sites were analyzed for 222Rn concentration using the RAD7 detector (Durridge Company, USA). The average concentrations of 222Rn were 46.1 ± 0.94, 65.3 ± 0.45, and 5.47 ± 0.25 Bq/L in the Hunza district, Nagar district, and background sites, respectively. Results showed that 222Rn concentrations of hot springs water were multifold higher than the background sites. 222Rn concentrations for hot springs water in Hunza-Nagar valley had surpassed the maximum contamination level set by the US environmental protection agency (USEPA). Humans' annual mean exposure dose rates of various age groups were calculated for the estimated lifetime cancer risk (ELCR) and non-cancer risks. The total annual mean exposure doses from 222Rn in water (EwTotal) values were (187 ± 3.80, 265 ± 1.84, and 22.2 ± 1.02 μSv/a) for infants (143 ± 2.92, 203 ± 1.40, and 17.0 ± 0.78 μSv/a) children, and (138 ± 2.80, 196 ± 1.35, and 16.4 ± 0.76 μSv/a) adults in the Hunza district, Nagar district, and background, respectively. Among the age groups of humans, infants showed a higher risk than others. Results showed that hot springs water consumption surpassed the world health organization threshold of 100 μSv/y for chronic or non-cancer and USEPA 0.1 × 10-3 for ELCR risks. The concentration of 222Rn showed a positive correlation (> 0.68) with hot springs' water temperature and pH suggesting a common origin.

Investigation of radioactivity level in drinking water resources and soil samples collected from the Hawraman villages, Iraq

In the present study, the RAD7 and NaI(Tl) techniques were utilized to determine the radon concentrations in drinking water resources and the natural primordial radionuclides in soil samples collected from Hawraman villages. The measured radon concentrations ranged from 1.7 ± 0.6 to 34.0 ± 2.8 Bq L^-1 with an arithmetic mean of 14.8 ± 1.2 Bq L^-1. This research demonstrates that roughly 54% of drinking water samples exceed the EPA-recommended level of 11.1 Bq L^-1. For adults, children, and infants, the total annual effective doses for the three types (D_ing, D_inh, and D_di) vary from 7.6 to 149.2 μSv y^-1 with an average of 65.0 μSv y^-1, 8.1-160.0 μSv y^-1 with an average of 69.7 μSv y^-1, and 10.5-207.0 μSv y^-1 with an average of 90.2 μSv y^-1.18.2%, 22.7%, and 36.4%, respectively, of the annual effective dose for adults, children, and infants exceeds the 100 μSv y^-1 level recommended by WHO and UNCEAR 2000. The activity concentrations of ²²⁶Ra, ²³²Th, and ⁴ K in soil samples varied from 10.9 ± 0.1 to 32.6 ± 0.2 Bq kg^-1, 18.3 ± 0.4 to 52.1 ± 0.6 Bq kg^-1, and 252.7 ± 2.5 to 585.6 ± 3.7 Bq kg^-1. The arithmetic mean concentrations of ²²⁶Ra, ²³²Th, and ⁴ K were determined to be 19.4 ± 0.2 Bq kg^-1, 36.2 ± 0.5 Bq kg^-1and 426.6 ± 3.2 Bq kg^-1, respectively. This research reveals that the average soil activity concentrations of ²²⁶Ra, ²³²Th, and ⁴ K are within the global average limits of 32, 45, and 420 Bq kg^-1, respectively. Comparing the concentrations to global averages, some soil samples revealed significant amounts of radionuclides, with around 18% of ²³²Th and 41% of ⁴ K. The computed radiological hazard indices of 100% of Ra_eq., 82% of D_out, 82% of E_out, and 95.5% of ELCR_out are all below the internationally recommended levels declared by Unscear 2000.

Culturomics of Bacteria from Radon-Saturated Water of the World's Oldest Radium Mine

Balneotherapeutic water springs, such as those with thermal, saline, sulfur, or any other characteristics, have recently been the subject of phylogenetic studies with a closer focus on the description and/or isolation of phylogenetically novel or biotechnologically interesting microorganisms. Generally, however, most such microorganisms are rarely obtained in pure culture or are even, for now, unculturable under laboratory conditions. In this culture-dependent study of radioactive water springs of Jáchymov (Joachimstahl), Czech Republic, we investigated a combination of classical cultivation approaches with those imitating sampling source conditions. Using these environmentally relevant cultivation approaches, over 1,000 pure cultures were successfully isolated from 4 radioactive springs. Subsequent dereplication yielded 121 unique taxonomic units spanning 44 genera and 9 taxonomic classes, ~10% of which were identified as hitherto undescribed taxa. Genomes of the latter were sequenced and analyzed, with a special focus on endogenous defense systems to withstand oxidative stress and aid in radiotolerance. Due to their origin from radioactive waters, we determined the resistance of the isolates to oxidative stress. Most of the isolates were more resistant to menadione than the model strain Deinococcus radiodurans DSM 20539T. Moreover, isolates of the Deinococcacecae, Micrococcaceae, Bacillaceae, Moraxellaceae, and Pseudomonadaceae families even exhibited higher resistance in the presence of hydrogen peroxide. In summary, our culturomic analysis shows that subsurface water springs contain diverse bacterial populations, including as-yet-undescribed taxa and strains with promising biotechnological potential. Furthermore, this study suggests that environmentally relevant cultivation techniques increase the efficiency of cultivation, thus enhancing the chance of isolating hitherto uncultured microorganisms. IMPORTANCE The mine Svornost in Jáchymov (Joachimstahl), Czech Republic is a former silver-uranium mine and the world's first and for a long time only radium mine, nowadays the deepest mine devoted to the extraction of water which is saturated with radon and has therapeutic benefits given its chemical properties. This healing water, which is approximately 13 thousand years old, is used under medical supervision for the treatment of patients with neurological and rheumatic disorders. Our culturomic approach using low concentrations of growth substrates or the environmental matrix itself (i.e., water filtrate) in culturing media combined with prolonged cultivation time resulted in the isolation of a broad spectrum of microorganisms from 4 radioactive springs of Jáchymov which are phylogenetically novel and/or bear various adaptive or coping mechanisms to thrive under selective pressure and can thus provide a wide spectrum of capabilities potentially exploitable in diverse scientific, biotechnological, or medical disciplines.