Radon In The Environment Research Articles

The sensitivity of innovative techniques for measuring low levels of radon in the environment using passive detectors

In recent years, there has been a significant surge in interest in measuring low radon levels in the environment. These measurements are valuable, particularly for identifying radon priority areas as required by the European Council Directive 2013/59/EURATOM and for research related to climate change. Due to the limited sensitivity of existing radon detectors/monitors in addressing these challenges, substantial efforts have been devoted to developing new designs. This report compares the sensitivity of several innovative designs with that of existing passive radon monitors. These novel designs incorporate alpha track detectors, including large area low background detectors, with activated carbon fabric used as an efficient radon adsorber/radiator. Recent innovative solutions to mitigate the impact of temperature and humidity on detectors using adsorbers are also discussed. The background signal of detectors intended for use in these novel designs is examined, and their sensitivity is evaluated. The findings demonstrate that these novel designs have the potential to significantly enhance the sensitivity of long-term radon measurements, surpassing the detectors currently in widespread use by more than an order of magnitude.

Characteristics of Thoron (220Rn) and Its Progeny in the Indoor Environment.

The present paper outlines characteristics of thoron and its progeny in the indoor environment. Since the half-life of thoron (220Rn) is very short (55.6 s), its behavior is quite different from the isotope radon (222Rn, half-life 3.8 days) in the environment. Analyses of radon and lung cancer risk have revealed a clearly positive relationship in epidemiological studies among miners and residents. However, there is no epidemiological evidence for thoron exposure causing lung cancer risk. In contrast to this, a dosimetric approach has been approved in the International Commission on Radiological Protection (ICRP) Publication 137, from which new dose conversion factors for radon and thoron progenies can be obtained. They are given as 16.8 and 107 nSv (Bq m−3 h)−1, respectively. It implies that even a small quantity of thoron progeny will induce higher radiation exposure compared to radon. Thus, an interest in thoron exposure is increasing among the relevant scientific communities. As measurement technologies for thoron and its progeny have been developed, they are now readily available. This paper reviews measurement technologies, activity levels, dosimetry and resulting doses. Although thoron has been underestimated in the past, recent findings have revealed that reassessment of risks due to radon exposure may need to take the presence of thoron and its progeny into account.

Factors controlling the distribution of radon (222Rn) in groundwater of a tropical mountainous river basin in southwest India

Studies on occurrence of radon in the environment are receiving growing attention worldwide due to its adverse impact on human health. Despite that, the dissolved radon in water is found to be a useful tracer in many hydrogeological studies. Although, several studies focused on the occurrence of high 222Rn in groundwater, the processes responsible for its variation is still not well understood. Hence, an attempt has been made in the present study to elucidate the underlying factors influencing the abundance 222Rn in hard rock (gneissic) aquifers of Karamana River Basin, southwest India. 222Rn in groundwater was analyzed in 71 dug wells during the pre-monsoon period of 2017.A large variability in 222Rn activities (170–68,350 Bq/m3) was noticed in groundwater and high activities were mainly seen in the khondalite formation. No significant dependencies between 222Rn activity and depth to water table, groundwater temperature and electrical conductivity were observed. However, majority of the presence of high 222Rn activity in groundwater matches with the location of lineaments. Furthermore, radium content in the host rock, degree of weathering and fracturing and the emanation coefficient of the rock were found to have an important bearing on the occurrence of radon in groundwater. The underlying factors influencing the abundance of radon in hard rock aquifers were also conceptualized. Thus, the study highlights the usefulness of 222Rn as a potential tool in delineating the macro-structural features like fractures/lineaments that are significant repositories of groundwater, which could be explored for groundwater development in hard rock terrains.

Remote real-time control of aerosol continuous monitoring for high radon concentration environments

In this study, we developed a new continuous aerosol monitoring device, which can be controlled by a remote server and transmit data over the Internet according to the TCP protocol. The user can remotely control the device and obtain the data measured in real time, which can be used to send alarms related to the concentrations of radioactive aerosols. This new device was applied to remotely measuring the concentrations of nuclides (uranium, plutonium, and beta) in radioactive aerosols and for reducing the effects of high radon in the environment based on the measurements. The experimental results demonstrated that this novel device can provide accurate test results and transmit the results to the administrator's location, and it can be remotely controlled in order to remain at a safe distance away from a dangerous measurement area.

The Radon Gas in Underground Constructions. Railway Tunnel of Alicante (Spain)

The presence of radon gas in constructions is an indicator of air quality. The study presented analyzes the amount of radon gas in the Railway Tunnel in Alicante. This infrastructure is very important for the city due to its social importance in facilitating urban mobility. radon gas is an element considered highly harmful to people by different scientific agencies in the field of medicine and health, including the World Health Organization (WHO). The main effect of the presence of radon in the environment of the human being is the risk of contracting lung cancer. This radioactive gaseous element is present in almost all building materials, and in the land in which the buildings are implanted. In this article the measurements made in the tunnel are provided and the levels obtained are analyzed according to their danger to humans. In Spain, the Technical Building Code (CTE) still does not contemplate the dose of radon that can hold a maximum of one building and how to contain it.

Radon: a radioactive therapeutic element

Abstract This paper presents selected issues related to the use of 222 Rn in therapeutic treatments. Radon is a radioactive element whose usage in medicine for more than 100 years is based on the radiation hormesis theory. However, owing to the radioactive character of this element and the fact that its alpha-radioactive decay is the source of other radionuclides, its therapeutic application has been raising serious doubts. The author points to potential sources and carriers of radon in the environment that could supply radon for use in a variety of therapies. Except for centuries-long tradition of using radon groundwaters, and later also the air in caves and underground workings, the author would also like to focus on soil air, which is still underestimated as a source of radon. The text presents different methods of obtaining this radioactive gas from groundwaters, the air in caves, mining galleries and soil air, and it presents new possibilities in this field. The author also discusses problems related to the transportation and storage of radon obtained from the environment. Within radon-prone areas, it is often necessary to de-radon groundwaters that are intended for human consumption and household usage. Also, dry radon wells are used to prevent radon migration from the ground into residential buildings. The author proposes using radon released from radon groundwaters and amassed in dry radon wells for radonotherapy treatments. Thanks to this, it is possible to reduce the cost of radiological protection of people within radon-prone areas while still exploiting the 222 Rn obtained for a variety of therapies. With regard to the ongoing and still unsettled dispute concerning the beneficial or detrimental impact of radon on the human organism, the author puts special emphasis on the necessity of strictly monitoring both the activity concentration of 222 Rn in media used for therapeutic treatments and of its radioactive decay products. Monitoring should be also extended to the environments in which such treatments are delivered (inhalatoriums, baths, saunas, showers, pools and other facilities), as well as to the patients – during and after the radonotherapy treatments. It is also essential to monitor the dose of radon and its daughters that is received by persons undergoing radon therapy. This should facilitate the assessment of the effectiveness of these treatments, which may contribute to a fuller understanding of the mechanisms of radon impact, and ionizing radiation in general, on the human organism. This will make it easier to ultimately confirm or reject the radiation hormesis theory. It is also essential to monitor the effective dose that is received by medical and technical staff employed to deliver the radonotherapy treatments.

Laboratory facility to create reference radon + thoron atmosphere under dynamic exposure conditions

Radon (222Rn) and thoron (220Rn) levels in the environment are typically subject to significant random and systematic variations. Creation in the laboratory of reproducible and controlled exposure conditions close to that in the real environment can be useful for testing 222Rn and 220Rn detectors and for research. In this report the design and performance of a novel laboratory facility with such functionality is presented. The facility allows the exposure of detectors under controlled dynamic as well as static activity concentrations of 222Rn and 220Rn (pure and mixed) and temperature. The temperature is measured and regulated within −15 °C ÷ +60 °C by a dedicated programmable thermostat. Different reference activity concentrations in the exposure vessel are made by regulating the flow-rate of the air that flushes 222Rn/220Rn activity from the sources towards the exposure vessel. Reference atmospheres that contain 222Rn, 220Rn or a specified ratio of the two can be created. Pilot experiments that demonstrate the feasibility of the approach are presented. They include follow-up of a pre-defined temperature profile (in the range −5 °C ÷ +35 °C), test of the correspondence between planned and measured 222Rn and 220Rn activity concentrations, follow-up of a pre-defined dynamic profile of 220Rn concentrations and test of the possibility to create mixed 220Rn/222Rn atmospheres (experimentally checked for ratio of the activity concentrations from 0.27 to 4.5). The results from the experimental tests are in agreement with the values obtained by the developed theoretical model. The proposed approach can be used to plan and create stationary and dynamic reference exposure conditions that are close to the real exposure regimes in the environment.

RADIUM AND RADON EXHALATION RATE IN SOIL SAMPLES OF HASSAN DISTRICT OF SOUTH KARNATAKA, INDIA.

The radon exhalation rate was measured in 32 soil samples collected from Hassan district of South Karnataka. Radon exhalation rate of soil samples was measured using can technique. The results show variation of radon exhalation rate with radium content of the soil samples. A strong correlation was observed between effective radium content and radon exhalation rate. In the present work, an attempt was made to assess the levels of radon in the environment of Hassan. Radon activities were found to vary from 2.25±0.55 to 270.85±19.16 Bq m-3 and effective radium contents vary from 12.06±2.98 to 1449.56±102.58 mBq kg-1 Surface exhalation rates of radon vary from 1.55±0.47 to 186.43±18.57 mBq m-2 h-1, and mass exhalation rates of radon vary from 0.312±0.07 to 37.46±2.65 mBq kg-1 h-1.

The Indoor Radon Concentration Measurement and Analysis in a University and its Adjacent Areas

Radon is a radioactive gas, high concentrations of radon in the environment can cause lung cancer, leukemia and other diseases. In this paper, indoor radon concentration in different places were measured and analyzed by using the RAD-7 radon monitor in a university and its adjacent areas. On-site measurements show that within 24 hours the indoor radon concentration versus time has certain regularity, different interior architectural decoration materials has a certain influence on the radon concentration, the radon concentrations in long confined spaces are significantly higher than those places frequently ventilated, floor height and ventilation conditions have a greater impact on the radon concentration. This research can provide a reference for future prevention and control of radon hazards.

Measurement and Application of Radium and Radon in the Environment

The measurement of low-level Ra and Rn isotopes in water samples has become increasingly convenient and accurate in recent years. I summarize these new and advanced techniques and then introduce their application fields in geophysical and environmental studies.

Radon in the environment and in dwellings in a uranium mining area in Eastern India: an overview

Radon has been extensively studied in the Singhbhum Thrust Belt (STB) of eastern India where mining and processing of uranium ore has been in progress for over four decades. Emanation from the soil is the main natural source of environmental radon. Releases from mine and emanations from waste rocks and tailings are the technological sources. Rn studies in the environment, dwellings and ground waters in STB are reviewed in this paper.

Radon and thoron daughter activities in the environment of the King George Island (West Antarctica)

Results of 253 gamma spectrometric analyses of radon daughters in soil and bedrocks of the King George Island (West Antarctica) are presented. Measured values range from 0.1 to 58.4 Bq/kg, and from 4.9 to 75.5 Bq/kg for 214Bi and 208Tl respectively, but most measurements fall in the lower part of this range due to predominantly basaltic character of the geological basement. Obtained gamma spectrometric data correspond well to very low soil gas radon content measured by means of Kodak LR115 being below 454 Bqm-3. Low soil gas radon content and characteristic type of architecture is responsible for low indoor radon activity in Arctowski Station being as low as 10- 15 Bqm-3. The highest 105 Bqm-3 indoor Rn activity has been measured in the greenhouse bungalow of the station. This increased value was probably connected with the presence of about 1000 kg of imported soil material in the greenhouse room of the bungalow. Local zones of increased uranium and thorium content, discovered as a result of radiometric mapping, can potentaily influence atmospheric radon used for meteorological interpretation.

Radon and thoron monitoring in the environment of Kumaun Himalayas: survey and outcomes

Monitoring of radon, thoron and their daughter products was carried out in houses of Kumaun Himalaya, India using LR-115 plastic track detectors. The measurements were made in residential houses from June 1999 to May 2000 at a height of 2.5 m from ground level using a twin chamber radon dosimeter. The twin chamber radon dosimeter can record the values of radon, thoron and their decay products separately. Maximum and minimum indoor radon and thoron concentrations were evaluated and activity concentrations of radon and thoron daughters were estimated. The resulting dose rates due to radon, thoron and their decay products varied from 0.04 to 1.89 μSv/h. A detailed analysis of the distribution of radon, thoron and their decay products inside the house is also reported. The observed dose rates inside the houses of Kumaun Himalaya were found to be lower than the ICRP recommended value of 200 Bq/m 3 and thus are within safe limits.

An improved scintillation cell for radon measurements

Scintillation cells like “Modified Lucas cells” are widely used for grab-sample measurements of radon in the environment including those developed in the laboratory for evaluation of radon diffusion coefficients of radon barriers, radon emanation powers in small samples of porous materials and radon concentrations in small chambers used for different research studies. In this paper we describe the main characteristics of an improved and practical scintillation cell developed in our laboratory. Experimental efficiency values obtained for different cell volumes ranged between 0.038 and 0.123 cpm/Bq/m 3. The effects of atmospheric pressure on the detection efficiency as a function of the diameter of the cell were also studied. In general, a decrease of 15% was observed when increasing the pressure from 827 to 1013 hPa.

Measurement of radon and radon progenies at the German radon reference chamber

The activity concentration of radon in the environment can vary over five orders of magnitude. Radon and its progenies thus concern all people involved in radiation protection as well as in low-level experiments. In the German radon reference chamber at the PTB, radon and its progenies are measured with different systems for α- and γ-spectrometry with the full set of environmental parameters, e.g. temperature, humidity and aerosol concentration being controlled. Control of air pressure is also possible by use of an extention chamber. The sampling and measuring technique for radon and its short-lived progenies at the German radon reference chamber are the basis for fundamental studies with regard to the understanding of the equilibrium factor and the unattached fraction of progenies. The facility also serves for the calibration of radon progeny detectors.

Bibliographic Collection - Radon in the Environment

Bibliographic Collection - Radon in the Environment

Radon in the environment

Radon in the environment

Radon in the environment

Radon in the environment

Radon in the environment

Radon in the environment

Radon in the environment

Radon in the environment