RAD7 Detector Research Articles

Assessment of the activity concentration of radon and its health hazard in surface water around the Rooppur Nuclear Power Plant (RNPP) site, Bangladesh

ABSTRACT Radon is a colourless, unscented, radioactive inert gas. As a gaseous element, Rn-222 can be effectively breathed in, leading to a health hazard. The main objective of this study is to measure the amount of Rn-222 concentration in surface water and its associated health hazards around the Rooppur Nuclear Power Plant (RNPP) construction site area in Bangladesh. Twenty water samples were collected each year (2022 and 2023) from different specific locations of the Padma River and investigated for radon concentration through a Durridge RAD7 detector with RAD H2O accessories. The range of radon activity in surface water measured from 0.070 ± 0.035 to 0.385 ± 0.211 BqL−1 with a mean activity of 0.194 ± 0.114 BqL−1 in the year 2022 and in the year 2023, the range of radon activity in surface water measured from 0.035 ± 0.070 to 0.455 ± 0.239 BqL−1 with an average activity of 0.228 ± 0.140 BqL−1. All the radon concentration results were below the recommended limits of WHO (100 BqL−1) and USEPA (11.1 BqL−1). The ranges of annual effective dose (AED) were from 0.1911 to 1.051 µSvy−1 and from 0.095 to 1.242 µSvy−1 in the years 2022 and 2023, respectively, which were lower than the AED recommended by WHO (0.1 mSvy−1). The mean values of excess lifetime cancer risk are 0.0021 × 10−3 and 0.0025 × 10−3 in the years 2022 and 2023, respectively, which were lower than the average standard value recommended by UNSCEAR (0.29 × 10−3). The result of this investigation can be applied as baseline data for radon concentration measurement in the under-construction nuclear power plant site area vicinity of Bangladesh.

Measurement of Radon Gas Concentration in Sources of Drinking Water in Makurdi, Benue State, Nigeria Using Radon Detector (RAD-7)

Study’s Excerpt Radon gas contamination across diverse drinking water sources within Makurdi, Nigeria, was investigated. The RAD-7 detector was used, and the results revealed elevated radon levels exceeding WHO limits in some specific locations. There is a need for targeted risk mitigation strategies and continuous monitoring of Radon gas contamination in the area. Full Abstract Concern over radon gas's potential health risks when used or ingested in homes is growing, as is the issue with its presence in sources of drinking water. In this study, water samples were collected from various locations in Makurdi, Benue State, Nigeria, and the amount of radon gas present was measured using the Radon Detector (RAD-7). The study used a methodical sampling strategy to gather water samples from wells, boreholes, and surface water bodies throughout various Makurdi locations. The gathered water samples were examined using the RAD-7 detector, a trustworthy and sensitive device for measuring radon gas. The radon levels ranged from trace levels (20.0 ) to higher quantities (122.0 ), raising worries about potential health implications for nearby people reliant on these water sources. Thirty (30) samples of water were gathered for this investigation. The samples' radon content ranged from 10.3 to 122.0 Bq L-1, which is within the World Health Organization's (WHO) allowable limit and other regulatory bodies (100 Bq L-1) except in the sample collected from Court 5 and Logo1, which was higher than the set limit. The results of the analysis demonstrated that there were large variations within the range of 0.61 0.39-11.80 1.85 and a mean of 57.36 in the amounts of radon gas in the water samples obtained from the different sources. More research and monitoring are advised to gain a complete understanding of radon distribution and to develop workable radon risk reduction plans for water sources.

Radon Concentration in Air and Evaluation of the Radiation Dose in Villages near Shizhuyuan, Southern Hunan, China

Radon is one of the important natural sources of radiation and pollutants. When radon and its progeny are inhaled by the human body, they can cause radiation damage to the respiratory system and can lead to lung cancer. Indoor and outdoor radon concentrations were measured in five villages near Shizhuyuan W-polymetallic deposit using a RAD7 detector; moreover, the corresponding radiation dose and lifetime risk probability were evaluated. The results show that the average value of indoor radon concentration was 216.6±121.1 Bq m−3, which is above the worldwide average indoor radon level of 40 Bq m−3, and the average outdoor value was 34.6±13.4 Bq m−3, which is higher than the worldwide outdoor average of 10 Bq m−3. A total of 42% of the dwellings investigated in our study had a higher radon level than the Chinese permissible indoor radon level of 200 Bq m−3. The total annual effective dose ranged from 5.21 mSv y−1 to 49.38 mSv y−1, with an average value of 14.63 mSv y−1, which is higher than the ICRP recommended value of 3–10 mSv y−1. This average total dose value corresponds to an average lifetime risk probability of 5.8% for residents in the whole study area.

Radon Concentration Level in Selected offices at Bells University of Technology, Ota, Ogun State

Radon, a radioactive gas that emanates naturally from the earth crust is accountable for about 50% of the effective dose of ionizing radiation received by humans. Most radon susceptiveness occurs in homes and work places, it comes from the natural disintegration of uranium in soil, rock and water and escalate to the air that we breath, hence it is important to monitor the actual level of exposure in most buildings. This work analysed the indoor radon concentration in air at twenty different offices of different building at Bells University of Technology using Rad7 detector. The mean measured radon concentration ranges from 0-56.7 Bq/m3 for all the study locations. The mean absorbed dose, equivalent dose and effective dose were calculated with the radon concentration which are 0.152 mGy/y, 3.045 mSv/y and 0.365 mSv/y respectively. The results obtained are below the world set limit as recommended by International Commission on radiological protection, except for office 7 which slightly exceed the recommended limit. Thus, the study concluded that good ventilation is very important in the reduction of radon concentration level in our work places.

Radon Levels and Risk Assessment due to its Ingestion and Inhalation from Groundwater of Lapai, North-Central Nigeria

Radon exposure through ingestion or inhalation from groundwater can be a significant public health concern due to its carcinogenic effects. This study assessed the health risks of radon exposure from groundwater in Lapai, Nigeria, using a Rad7 detector to measure radon concentration levels. The measured concentrations ranged from 5.36 ± 0.22 BqL-1 to 0.52 ± 0.06 BqL-1 with an average value of 2.82 ± 0.14 BqL-1. The annual effect dose due to ingestion of Radon obtained varies in the range of 2.76 to 28.34 μSva-1, 1.02 to 10.43 μSva-1, and 1.33 to 13.69 μSva-1 for infants, children, and adults, respectively. While the effective dose per year from inhalation of Radon released from water by adults has values in the range of 1.31 to 13.50 μSva-1. Radon levels were within permissible limits of UNSCEAR and USEPA, and the annual effective doses from inhalation and ingestion were within WHO's safe range. Nonetheless, monitoring is advised, especially during the rainy season when contamination levels may increase.

Determination of radon concentration in bottled drinking water of Dhaka City

ABSTRACT Among all natural radiation sources, exposure to radon (222Rn) is considered as the most hazardous to human health. Recognizing the significance of water in preserving a healthy life style, assessing the 222Rn activity in drinking water is crucial. The 222Rn activity concentration was measured in 20 different branded bottled drinking waters purchased from Dhaka city using both alpha and gamma-ray spectrometry systems. Activity concentrations of 222Rn in bottled water obtained via RAD7 detector varied from 0.1 ± 0.02 Bq/L to 0.42 ± 0.01 Bq/L with an average value of 0.26 ± 0.02, while the value varied from 0.12 ± 0.01 Bq/L to 0.52 ± 0.31 Bq/L with an average value of 0.29 ± 0.09 by HPGe detector. The obtained results show lower concentrations when compared with other studies around the world as well as the US-EPA reference level of 11.1 Bq l−1 or 300 pCi l−1. The total annual effective dose calculated for different age groups and internal organ doses were found below the action level recommended by WHO (0.1 mSv y−1) and ICRP (3–10 mSv y−1), due to 222Rn, 3H and 40K in drinking water. Based on the obtained radon concentration and concomitant dose values, this study suggested negligible health hazards due to the consumption of bottled drinking water in Bangladesh. The results of this study could serve as a reference data for future studies in the area and beyond.

Radon concentrations in the serum of blood and urine of smokers using RAD-7 detector

Radon concentrations in the serum of blood and urine of smokers using RAD-7 detector

The spatial distribution of Radon-222 in Soil: SaTScan and Geographic Information System

This study identifies clustering and hotspot radon concentrations in the city of Najaf's soil samples with the RAD-7 detector. The radon concentration varied from 0.16 kBq /m3 to 10.04 kBq /m3 with an average value of 3.69 ±2.26 Bq/m3 were a normal level according to the Sweden Criteria. Radon concentrations were mapped using a geographic information system approach, and a clustered distribution was found using local spatial autocorrelation analysis. Three regions were found to be H-H clusters (hot spots) based on the Moran index study of spatial autocorrelation within local regions, whereas five regions were found to be L-L clusters (cold spots). Three important spatial clusters were found using a spatial scan analysis.

Radon concentrations in the serum of blood and urine of smokers using RAD-7 detector

Radon concentrations in the serum of blood and urine of smokers using RAD-7 detector

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.

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.

Characteristics of Indoor and Soil Gas Radon, and Discussion on High Radon Potential in Urumqi, Xinjiang, NW China

Urumqi City, located in the northwest of China, is a city with a high indoor radon concentration in a nationwide indoor radon survey in China. This study focuses on the assessment of the indoor radon level and its distribution in this city. Indoor radon measurement using RAD7 and solid nuclear track detector (SSNTD), soil gas radon measured by RAD7, and the determination of the specific activity of uranium and radium in soil samples by a high pure germanium spectrometer were performed from 2021 to 2023. The results reveal a wide range of indoor radon concentrations in Urumqi, with anomalies above 400 Bq/m3 in some dwellings. The arithmetical and geometric mean values of indoor radon concentration are 80 ± 77 Bq/m3 and 58 Bq/m3, respectively. The geometric mean value of radon measured by SSNTD is 101 Bq/m3. The distribution of areas with a high indoor radon concentration is spatially consistent with deep and large active faults or overlapping and intersection zones of multiple groups of faults. It is recommended to conduct a more comprehensive investigation and research into the elevated radon potential and radioactivity associated with building materials.

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 ± 0.25Bq/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 ± 1.02μSv/a) for infants (143 ± 2.92, 203 ± 1.40, and 17.0 ± 0.78μSv/a) children, and (138 ± 2.80, 196 ± 1.35, and 16.4 ± 0.76μSv/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 100μSv/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.

Effective dose (ingestion and inhalation) due to radon from tap water samples in children at primary schools in Najaf city, Iraq

Abstract This study focuses on the evolution of radon concentrations in tap water samples of primary schools in Najaf city using a RAD-7 detector. Annual effective doses in children were calculated. A Geographic Information System technique was used for the mapping of radon concentrations, annual effective dose (AED) for ingestion, and inhalation. It was found that the average value of AED due to radon ingestion was 0.236 ± 0.020 μSv/year, while that due to radon ingestion was 0.015 ± 0.0001 nSv/year. Moreover, the range in value of the total AED in μSv/year was 0.015–1.171, with an average value of 0.236 ± 0.020. Radon concentrations in most samples of water comply with the world-wide limits that are approved by WHO and ICRP which state that safe limits (0.5 and 0.4 Bq/L), respectively. Furthermore, all results of the total AED due to radon ingestion and inhalation assessment from radon concentrations in tap water samples collected from the primary schools in Najaf city when used as drinking water were within the global limitations of the WHO. One may conclude that from the results of the AED in children (7–12 years), there is no danger of radon concentrations in the case of human consumption.

Dose assessment for radon and thoron concentrations in iraqi thermostone bricks

This research aims to measure radon (222Rn) and thoron (220Rn) concentrations for selected thermostone bricks samples produced in Iraq. 222Rn and 220Rn concentrations were measured using the active method (RAD7 detector). Also, the inhalation dose for the year was calculated using the 222Rn and 220Rn concentrations. The results of this study indicated that the range of radon concentration values was between 8.00 Bq/m3 to 66.50 Bq/m3; its mean value was 28.22±3.89 Bq/m3. At the same time, the values of thoron concentrations ranged from 27.10 Bq/m3 to 129.00 Bq/m3, with a mean value of 55.46±7.15 Bq/m3. Also, the mean dose value associated with radon and thoron was 0.71±0.098 mSv/y and 0.31±0.039 mSv/y, respectively. According to preliminary research, the concentration of thoron in the current study was higher than that of radon except for two samples. In general, the values of doses from Iraqi thermostone brick samples were within the action level recommended by ICRP, 1993. Therefore, all samples in the present study didn't significantly affect the dose.

Detection of Radon Exhalation from Various Building Materials Using CR-39, RAD7, and Biosensors

Study aimed to design and manufacture two biosensors, namely BIOS-I and BIOS-II, for 222 Rn and Pb+2 measurements in building materials and soil samples. For comparison, the conventional detectors of RAD7 and CR-39 were used. The biosensor material used was based on ssDNA rich guanine or primer. The two biosensors have a difference in the sequence of the nitrogenous bases. The measurement revealed that the average of 222 Rn exhalation by the BIOS-Ι was 373.30 Bqm-3, while the BIOS-ΙΙ was 342.29 Bqm-3. The average 222 Rn exhalation measured by the CR-39 detector was 326.17 Bqm-3, whereas by the RAD7 detector it was 319.95 Bqm-3. This study found that 222 Rn exhalation in the Indian and Chinese granites, soil, and Iraqi mosaic samples was higher than the limits recommended by WHO, while the rest of the samples were within the permissible limits. It is also known that there is a very weak positive correlation between BIOS-Ι or BIOS-ΙΙ and humidity, while a very weak negative correlation was found between them and temperature. There is a very strong positive correlation between radon exhalation recorded by RAD7 and humidity. On the other hand, there are no statistically significant differences between BIOS-I and BIOS-II at (level 0.01), while there are statistically significant differences between BIOS-I and CR-39 or RAD7 at level 0.01. It was concluded that the manufactured biosensors have better detection for radon than RAD 7 and CR-39 detectors .

Advancement of a Liquid Scintillation Counter and Semiconductor Alpha Spectroscopy Detector to Estimate the Radon Concentration in Groundwater

Radon is one of the most natural forms of radiation for human exposure. However, high-accuracy measurement of natural radon in water samples is very challenging due to the background correction, data acquisition, and sampling time. Liquid scintillation counter (LSC) and semiconductor alpha spectroscopy detectors are the most commonly used methods of determining radon concentration in water. The present study utilizes both methods to estimate radon in groundwater collected from various locations in the northeast region of Saudi Arabia. The estimated radon concentrations using Hidex 300SL are compared with a Durridge RAD7 detector to evaluate each apparatus’s abilities, advantages, and disadvantages. Both methods show radon concentrations between 0.1 and 3.20 Bq/L with an average of 0.96 Bq/L, with a standard deviation of 0.82 Bq/L. The estimated values are found to be in the safe limit recommended by the USEPA and EAEC and are far below the safe level recommended by UNSCEAR and the WHO. Comparing the estimated radon concentration using the two methods shows that although the two devices have many advantages and disadvantages based on the two different techniques, the experimental results are almost the same with experimental error.

Radon in groundwater sources of Bosso Community in North Central Nigeria and concomitant doses to the public

Realizing the probable health hazards from radon exposure, potable groundwater samples (hand-dug wells and boreholes) in the Bosso community of North Central Nigeria were collected and assayed for radon concentration. Durridge RAD-7 detector together with RAD-H2O accessories was employed in this study. The committed effective dose to different ICRP age groups was computed using various parameters including the annual water consumption characteristics. The mean 222Rn activity in water samples from hand-dug wells and boreholes were 9.81 ± 1.85 Bq/L and 24.78 ± 2.48 Bq/L respectively. The average whole-body committed effective dose due to ingestion and inhalation of waterborne radon from the two groundwater sources are 0.026 mSv/y and 0.067 mSv/y for hand-dug wells and boreholes respectively, which are below the safety threshold of 0.1 mSv/y recommended by the European Union. The results showed that there is no significant radiation threat to public health from inhalation and ingestion of waterborne radon within the community.

Comparison of Radon Gas in Different Water Samples at Al Haidariya City, Iraq

This study aims to measure the radon (222Rn) concentrations in the three types of water (groundwater, surface water, and health drinking water) in Al Haidariya city at Al-Najaf governorate, Iraq using RAD-7 detectors. The results show that the average of 222Rn in groundwater, surface water, and health drinking water were (0.276 Bq/L, 0.182 Bq/L and 0.132 Bq/L3) respectively, whereas the average of annual effective dose was (0.706 μSv/y,0.46 μSv/y and 0.337 μSv/y), respectively, While lifetime cancer risk (×10-4) with an average (0.027, 0.018 and 0.013) respectively. According to the results of 222Rn, the samples can be arranged in order groundwater, surface water and health drinking water. The results of the radon concentrations and the rate of annual effective dose for all water samples were significantly lower than the USEPA and WHO recommended respectively. The environmental effects of radioactive radon gas are almost non-existent, because the lifetime risk of cancer in all samples is less than the permissible safety limit for healthy drinking water, and therefore it does not affect human health.

In-situ radon-in-water detection for high resolution submarine groundwater discharge assessment

Submarine groundwater discharge (SGD), including both land-based fresh groundwater that enters the ocean from coastal aquifers as well as recirculated seawater that is continuously recharged and discharged on the seabed, has been considered as an important component of the global water and biogenic element (e.g., nitrogen, phosphorus, silicon and carbon) sources and a significant pathway for material exchange at the land-sea interface of coastal ecosystems. Some researchers reported that SGD associated nutrient additions to coastal waters have caused unwanted ecological issues, including red tides, coastal acidification and hypoxia. Natural radon isotope (222Rn, t1/2 = 3.8 d) is an excellent tracer for studying SGD and other oceanographic processes including air-sea gas exchange, sediment-water diffusion, and earthquake prediction. However, the conventional radon measurement methods suffer many technical disadvantages. We consequently developed a convenient submersible radon determination approach (“OUC-Rn”) using a commercial pulsed ionization chamber (PIC) radon sensor and gas extraction membrane module to produce high precision and high resolution observations. We demonstrate the radon degassing efficiency of the membrane contactor is comparable to the shower-head type air-water exchanger but is independent of operating position. The radon measurement efficiency of the PIC is 2-fold higher than the RAD7 detector and is far less influenced by moisture. We successfully deployed the system in 2.5 meters water depth over a 100 hours period in an anthropogenic influenced bay. Based on our high temporal resolution observations, the SGD flux was estimated to be 0-43.0 cm/d (mean: 25.4 ± 14.5 cm/d). The SGD fluxes pattern plotted together with the tidal variations revealed that tidal pumping may be the main force driving seawater recirculation into aquifers and thus affecting nutrient, carbon and other dissolved matters dynamics in coastal regions.