10ml of each sample was added into a vial containing 10ml of toluene based cocktail (scintillator) using a hypodermic syringe. The vials were tightly capped and shaken vigorously for three (3) minutes to extract radon- 222 in water phase into the organic scintillator. In a similar manner a blank sample for the background was prepared using distilled water that has been kept in a glass bottle for at least 21 days. The prepared samples were allowed to stand undisturbed for at least three (3) hours each in order for Rn-222 and its alpha decay products attain equilibrium before counting.
The activity is converted into Bq/m 3 by means of a custom calibration factor. The quality of calibration is verified in-house by comparison with other methods of determining the radon222 activity by volume (Kodalpha passive dosimeters and Alphaguard monitor). The measurement of radon222 activity by volume and the margin of uncertainty of each measurement are shown in the last two columns of table T1 on the next page.
U and 226 Ra in the water – rock system present in the areas especially in Ofukolo and Ede – Adejo areas which posed a greater health risk when ingested along with water , because well sunk in areas with underground rock tend to show high content of granites to which radon is associated, in which radon-222 from fractures and cavities in rocks and in the regions influenced by local and remote anthropogenic radon sources . Another reason that are attributed to this high radon concentration are human activities such as farming and other natural phenomenon such as weathering and volcanic action can also influence water radon content . The results have shown a range of 222Rn concentration between 3.01±2.00 Bq/L to 18.24±1.83 Bq/L with a mean radon concentration of 9.64Bq/L and an average mean radon concentration of 10.23 Bq/L recorded for the study location. 75% of the water samples were found to be above the maximum contamination level of 11.1Bq/L set by , 10.0Bq/L set by  and . The annual effective dose by ingestion for
Radon222 gas is a radioactive, colorless and odorless element that can cause lung cancer and stomach in humans with alpha-ray emissions. An important source of Radon222 is the output water in springs, especially hot springs. In this cross-sectional study, concentration of Radon222 in 12 water samples collected from Genow hot water were measured by Radon meters RTM1688-2 model. Then, the mean concentration of Radon222 and effective dose from drinking water with standards limits were compared. The mean and range of concentration of Radon222 was 684±265 Bq/m P
By contrast, measurement of a surface-emitted atmo- spheric tracer with appropriate physical properties (e.g., sim- ple source and sink characteristics), which responds directly to atmospheric mixing processes, has the potential to pro- vide a more consistent and representative method by which to identify PTI events. Such a method should be uniformly applicable, allowing seasonal changes in the number and du- ration of such events to be determined. Furthermore, once a representative number of events have been identified, season- ally dependent threshold concentrations of the tracer could be determined to help gauge the severity of the inversion events and characterize the meteorological conditions with which they are associated. The naturally occurring radioac- tive gas radon ( 222 Rn) is an ideal candidate for this task. The use of radon as a tracer in atmospheric studies dates back from the early 1900s (Eve, 1908; Satterly, 1910; Wigand and Wenk, 1928; Wright and Smith, 1915). In particular, how- ever, radon has achieved considerable credibility in the field of atmospheric science as an indicator of vertical mixing and transport near the Earth’s surface from the 1960s until present (Moses et al., 1960; Kirichenko, 1962; Cohen et al., 1972; Allegrini et al., 1994; Perrino et al., 2001; Sesana et al., 2003; Galmarini, 2006; Avino and Manigrasso, 2008; Cham- bers et al., 2011, 2015, 2019; Williams et al., 2011, 2013, 2016; Pitari et al., 2014; Wang et al., 2016).
This study demonstrates how the radon-222 ( 222 Rn) concentration of soil gas at an active fault is sensitive to cumulative recent seismicity by examining seven active faults in western Japan. The 222 Rn concentration was found to correlate well with the total earthquake energy within a 100-km radius of each fault. This phenomenon can probably be ascribed to the increase of pore pressure around the source depth of 222 Rn in shallow soil caused by frequently induced strain. This increase in pore pressure can enhance the ascent velocity of 222 Rn carrier gas as governed by Darcy's law. Anomalous 222 Rn concentrations are likely to originate from high gas velocities, rather than increased accumulations of parent nuclides. The high velocities also can yield unusual young gas under the radioactive nonequilibrium condition of short elapsed time since 222 Rn generation. The results suggest that ongoing seismicity in the vicinity of an active fault can cause accumulation of strain in shallow fault soils. Therefore, the 222 Rn concentration is a possible gauge for the degree of strain accumulation.
This part of ISO 11665 gives guidelines for estimating the radon-222 surface exhalation rate over a short period (a few hours), at a given place, at the interface of the medium (soil, rock, laid building material, walls, etc.) and the atmosphere. This estimation is based on measuring the radon activity concentration emanating from the surface under investigation and accumulated in a container of a known volume for a known duration.
Abstract. Dual-flow-loop two-filter radon detectors have a slow time response, which can affect the interpretation of their output when making continuous observations of near- surface atmospheric radon concentrations. While concentra- tions are routinely reported hourly, a calibrated model of de- tector performance shows that ∼ 40 % of the signal arrives more than an hour after a radon pulse is delivered. After investigating several possible ways to correct for the detec- tor’s slow time response, we show that a Bayesian approach using a Markov chain Monte Carlo sampler is an effective method. After deconvolution, the detector’s output is redis- tributed into the appropriate counting interval and a 10 min temporal resolution can be achieved under test conditions when the radon concentration is controlled. In the case of ex- isting archived observations, collected under less ideal con- ditions, the data can be retrospectively reprocessed at 30 min resolution. In one case study, we demonstrate that a decon- volved radon time series was consistent with the following: measurements from a fast-response carbon dioxide monitor; grab samples from an aircraft; and a simple mixing height model. In another case study, during a period of stable nights and days with well-developed convective boundary layers, a bias of 18 % in the mean daily minimum radon concentration was eliminated by correcting for the instrument response.
The strong gradients of radon between the reservoirs are used for applications in aquatic systems. For example, 222 Rn has been used as a tracer for the examination of the air-sea gas exchange (Roether and Kromer, 1978; Kawabata et al., 2003) or the estimation of vertical and horizontal mixing near the bottom boundary of lakes (Imboden and Emerson, 1984; Colman and Armstrong, 1987). Radon is particularly well suited to study groundwater-surface water interaction, because activity concentrations in groundwater (on the or- der of 1 to 100 kBq m −3 , depending on the lithology) are much higher than in surface water (about 1 to 100 Bq m −3 ). This contrast has been used to study groundwater recharge and flow in the vicinity of rivers (Hoehn and von Gunten, 1989; Schubert et al., 2006). Furthermore, radon has been applied successfully and quite extensively in the investiga- tion of submarine groundwater discharge (e.g. Cable et al., 1996; Corbett et al., 1999, 2000; Crusius et al., 2005). Simi- larly, some studies used radon to asses groundwater exfiltra- tion into lakes (Corbett et al., 1997; Tuccimei et al., 2005; Trettin et al., 2006).
In rural areas, groundwater is more likely to be the source of drinking water, cooking, cleaning, bathing, and also agricultural activities. Nowadays, most people who use sources of groundwater are not aware of the hazards of radioactive sources from groundwater resources. They use the water source to carry out daily activities, without knowing the presence of radioactive sources in the water. Groundwater is being contaminated due to agricultural runoff or disposal of liquid waste. 226 Ra maybe mobile in surficial environment, specifically in the reducing environment but at high level of 226 Ra it can cause health risks. Meanwhile 222 Rn has the ability to migrate through the pores of the media through by diffusion process, such as through the rock materials. In this study, the method used for the evaluation of 222 Rn and
concentrations of 222Rn are more worrisome to the water users, especially its effects on health to the residents. By drinking water from groundwater, it will increase the risk of human exposure to radiation effects. Almost 90% of stomach cancer deaths caused by inhaling radon released to the indoor air from water. Only about 10% of the deaths were from cancers of internal organs, mostly the stomach, caused by ingestion of radon in water (USEPA, 1999). Cothern et al. (1986) proved that there was a risk of death of about 1-7% from lung cancer for the people of the United States. Most cancer associated with indoor radon levels in buildings due to groundwater resources.
When disintegrating, radon emits alpha particles and generates solid decay products, which are also radioactive (polonium, bismuth, lead, etc.). The potential effects on human health of radon lie in its decay products rather than the gas itself. Whether or not they are attached to atmospheric aerosols, radon decay products can be inhaled and deposited in the bronchopulmonary tree to varying depths according to their size  .
Abstract. Although atmospheric 222radon ( 222 Rn) activity concentration measurements are currently performed world- wide, they are being made by many different laborato- ries and with fundamentally different measurement prin- ciples, so compatibility issues can limit their utility for regional-to-global applications. Consequently, we conducted a European-wide 222 Rn / 222 Rn progeny comparison study in order to evaluate the different measurement systems in use, determine potential systematic biases between them, and estimate correction factors that could be applied to har- monize data for their use as a tracer in atmospheric appli- cations. Two compact portable Heidelberg radon monitors (HRM) were moved around to run for at least 1 month at each of the nine European measurement stations included in this comparison. Linear regressions between parallel data sets were calculated, yielding correction factors relative to the HRM ranging from 0.68 to 1.45. A calibration bias be- tween ANSTO (Australian Nuclear Science and Technol- ogy Organisation) two-filter radon monitors and the HRM of ANSTO / HRM = 1.11 ± 0.05 was found. Moreover, for the continental stations using one-filter systems that de- rive atmospheric 222 Rn activity concentrations from mea- sured atmospheric progeny activity concentrations, prelim-
mechanisms influencing indoor radon levels in many buildings . It was reported that a world wide average of 60.4% of indoor radon comes from the ground and surrounding soil of buildings . Information on the spatial variability of radon exhalation rate would be useful for identifying areas with a risk of high radon exposure. On the other hand, the well understood chemical behavior (inert gas) of radon222 Rn and its convenient half life
exposure measurements, however, the results from such studies may be uncertain. Many additional assumptions are needed when risks estimated in miner studies are extrapolated to residential exposure conditions (3,10).Taking these circumstances into account, there has been great interest in developing direct estimates of residential risk for the general population using case–control studies. The environmental conditions in mines and homes are quite different. For a precise evaluation of radon exposures, the contribution of Thoron should be considered if the radon level is low in homes. Its presence often results in misleading estimation of radon concentrations. Before conducting a case–control study on residential radon exposures, it is important to understand those characteristics in the study area (10).
neighbour read a newspaper article about the dan- gers of radon gas causing cancer. Her friend pur- chased a testing kit and found that the levels in her home were 4 times the maximum acceptable limit. As a result, C.M. is very concerned for the health of her 8-year-old twins, her husband, and herself, as she thinks radon levels could also be elevated at her house. Everybody at home is completely asymptom- atic, but she wants to clarify the dangers of radon gas and is requesting guidance about what to do.