Determination of Radon Concentration in Drinking Water Resources of Villages Nearby Lalehzar Fault and Evaluation the Annual Effective Dose
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Determination of radon concentration in drinking water resources of villages nearby Lalehzar fault and evaluation the annual effective dose Mohammad Malakootian, Zahra Darabi Fard & Mojtaba Rahimi Journal of Radioanalytical and Nuclear Chemistry An International Journal Dealing with All Aspects and Applications of Nuclear Chemistry ISSN 0236-5731 Volume 304 Number 2 J Radioanal Nucl Chem (2015) 304:805-815 DOI 10.1007/s10967-014-3845-z 1 23 Your article is protected by copyright and all rights are held exclusively by Akadémiai Kiadó, Budapest, Hungary. This e-offprint is for personal use only and shall not be self- archived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. 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The link must be accompanied by the following text: "The final publication is available at link.springer.com”. 1 23 Author's personal copy J Radioanal Nucl Chem (2015) 304:805–815 DOI 10.1007/s10967-014-3845-z Determination of radon concentration in drinking water resources of villages nearby Lalehzar fault and evaluation the annual effective dose Mohammad Malakootian • Zahra Darabi Fard • Mojtaba Rahimi Received: 7 October 2014 / Published online: 20 December 2014 Ó Akade´miai Kiado´, Budapest, Hungary 2014 Abstract The radon concentration has been measured in over 50 % of received effective dose from natural sources [1]. 44 drinking water resources, in villages nearby Lalehzar 222Rn is colorless, odorless, without taste and eight times fault in winter 2014. Some samples showed a higher con- heavier than the air that can be found in different concentra- centration of radon surpassing limit set by EPA. Further, a tions in soil, air and various kinds of water [2]. sample was taken from water distribution networks for Radon released from decay of uranium in all soil and these sources of water. Soluble radon concentration was rocks almost but its concentration in particular geological measured by RAD7 device. Range radon concentration was materials and locations is different [3]. Abnormal changes in 26.88 and 0.74 BqL-1 respectively. The maximum and radon levels in many areas have been identified by active minimum annual effective dose for adults was estimated at faults [4]. Shell cuts such as fractures and faults in various 52.7 and 2.29 lSvY-1, respectively. Reducing radon from aspects facilitate degassing flux from earth into hydrosphere water before use is recommended to improve public health. and atmosphere [5]. Radon gas can easily transfer into the atmosphere, surface dwelling and groundwater through Keywords 222Rn Á Lalehzar fault Á RAD7 Á Effective fragmented rocks and faults [6]. Radon in drinking water dose Á Drinking water causes human exposure via drinking and inhalation due to release of radon into indoor air is dangerous. Use of water rich in radon for washing and cooking at home can increase Introduction concentration of this gas in indoor air [7]. With inhalation of radon gas, the daughter products with short half-life caused 222Rn is a natural radioactive noble gas and the most impor- by the degeneration of 218Po and 214Po deposits in lung tis- tant resource of natural ionizing radiation which has existed sue. They emit highly ionizing alpha particles that react with since earth formation. This gas with a half-life of 3.82 days is biological tissue of lung and cause DNA damage, which is an produced in the earth’s crust from decay of 226 Ra in 238U important step in carcinogenesis [8]. High levels of this gas decay chain. Inhaled radon and its products decay is allocated in water will lead to gastric cancer [9]. Absorbed radon by body through drinking will enter the blood circulatory sys- tem. It will destroy thereby releasing alpha particles and the M. Malakootian (&) Environmental Health Engineering Research Center and result of its radioactivity leaves in tissue [10]. Generally, Department of Environmental Health, Kerman University of bone marrow and kidney receive smaller dose [11]. Radon Medical Sciences, Kerman, Iran gas is introduced as a carcinogenic gas by World Health e-mail: [email protected] Organization [12]. The radon concentration was -3 Z. Darabi Fard 0.42–10.52 Bqdm in a study by Bem and colleagues in Department of Environmental Health, Kerman University of 2014 in Poland on water samples of drinking water distri- Medical Sciences, Kerman, Iran bution network. The average of annual effective dose from ingestion and inhalation was reported 1.15 and 11 lSvY-1, M. Rahimi Department of Physics, Vali-e-asr University of Rafsanjan, respectively [13]. A research was performed by Somashekar Rafsanjan, Kerman, Iran and colleague in 2010 in India on 16 samples of drinking well 123 Author's personal copy 806 J Radioanal Nucl Chem (2015) 304:805–815 water in varahi area and 14 samples of well water in Mark- Test method andeya area. Radon concentration in the two studied regions was 0.2–10.1 and 2.21–27.3 BqL-1, respectively. The radon The study is cross sectional and was conducted during concentrations of 21.4 % of water samples in Markandeya winter 2014 at the Environmental Health Engineering area are more than permissible limit by EPA (11.1 BqL-1). Research Center of Kerman University of Medical Sci- The annual effective doses of all samples were less than the ences. Drinking water samples were collected from villages WHO limits [14]. A study was conducted in 2014 in Iran by nearby ‘‘Lalehzar fault’’. Lalehzar fault is located at 56 to Malakootian and colleague on the sources of drinking water 57 degrees east length and 29 to 30 degrees north latitude and also drinking water network of Mehriz villages of Yazd and also about 16 km far from south of Bardsir. The length province. Radon concentrations of samples ranged from of Lalehzar fault is approximately 84 km and its trend is 0.187 to 14.8 BqL-1. The lowest annual effective absorbed northwest–southeast. The slope of this fault is towards the dose was 0.0005 mSvY-1 and the maximum amount was south-west. The mechanism of the fault is strike-slip 0.04 mSvY-1 [15]. The radon concentrations of ground- compressional. It is located at boundary of young Quater- water were reported as 1.58–345.10 BqL-1 by Idriss et al. in nary deposits with Eocene volcanic rocks in Cheheltan Khartoum state in 2011. The 14 reported cases for annual Mountains and from the other side is at Oligocene sedi- effective dose due to ingestion were more than WHO stan- mentary rocks with Quaternary travertine border in the dard [16]. A study in 2014 by Moldovan et al. was conducted north of the volcano Bidkhan and also the boundary of on drinking water in Bita-Stei in Romania. The average Quaternary with Neogene sediments and Eocene volcanic radon concentration in the wells, springs and tap water was rocks in Lalehzar Mountains. Geomorphic evidence such obtained 35.5, 18.5 and 6–9 kBqm-3, respectively. Effective as diversion canals, blocking the path of streams, cliffs, the dose was ranged from 4.78 to 338.43 lSvY-1, respectively spring that formed Travertine, smashing and disorganiza- [17]. So protect people from the adverse consequences of tion in sediments are the key indicators that represent successive radiation of radiation is necessary and important. activity of Lalehzar faults [18]. The position of Lalehzar So evaluation of radon concentration in drinking water fault is shown in (Fig. 1). resources of villages nearby Lalehzar fault and estimation Forty four samples were collected from drinking water annual exposure of individuals as a basic step to improve sources in villages around Lalehzar fault (15 wells, 21 public health is as the aim of this study. springs and 9 subterranean) within a 15 km radius of the Fig. 1 The position of Lalehzar Fault 123 Author's personal copy J Radioanal Nucl Chem (2015) 304:805–815 807 fault. In some samples, the radon concentration was more recording sampling time and reading time. Radon con- than EPA standard so another sample was taken and ana- centrations were determined at the moment of sampling by lyzed from that source for insurances. Further, a sample using Eq. (1). was taken from water distribution networks for these C ¼ C eð0:693=TÞt ð1Þ sources (20 samples of tap water). 250 mm brown vials 0 222 222 with Teflon caps were used for sampling. Sampling was C Rn concentration at reading time, C0 Rn concen- conducted slowly so as not to create turbulence in water tration at the moment of sampling (actual concentration), resources. The vial was filled with water below the water T half-life of 222Rn equal to 3.8 days or 91.2 h, t time of surface and the cap was placed on it under the water. To sample storage, geological map of Bardsir with scale of 1: avoid formation of bubbles, the sample vial was held 1,000,000 was used to more accurate geological study [19]. upside down. In the sampling of well water, after opening Figure 2 shows the location of sampling points relative to the faucet water for 10 mins, a bucket was placed under- water resources in the study area. water and a tube placed in it. Water poured into the bucket with no elevation. The sample container was then inserted Measurement of radon concentration gently into the bucket and the cap was placed on it under the water after filling.