Risk assessment of radon in drinking water in Khetri Copper Belt of Rajasthan, India.

Exceptionally high concentrations of radon have been found in drinking water originating from hand pumps in Khetri Copper Belt of Rajasthan. Radon concentration was determined using Durridge RAD7 professional electronic radon detector. The measured radon concentration ranged from 12.5 ±â€¯1.5 to 862 ±â€¯38 Bq l-1. About 35% of the drinking water samples showed radon concentrations above the European Union's parametric value of 100 Bq l-1. The high radon concentration obtained in groundwater is due to local natural geology. The total annual effective doses due to ingestion and inhalation of radon in drinking water varied from 0.10 to 6.7 mSv y-1 for infants, 0.06-3.8 mSv y-1 for children and 0.06-4.4 mSv y-1 for adults.

Radon levels in drinking water of Fatehabad district of Haryana, India.

Radon concentrations were measured in 59 groundwater samples collected from Fatehabad district of Haryana, India. The measurements were performed by RAD7 an electronic radon detector manufactured by Durridge Company Inc. The measured radon concentration ranged from 1.4 to 22.6Bql-1. 14% of the groundwater samples were above the United States Environmental Protection Agency recommended value for radon in water. The annual effective dose for ingestion and inhalation was also evaluated in this research. The total annual effective dose due to ingestion and inhalation of radon in drinking water varied from 14.1 to 221.8µSvy-1.

ASSESSMENT OF AGE-DEPENDENT RADIATION DOSE DUE TO INTAKE OF URANIUM AND THORIUM IN DRINKING WATER FROM SIKAR DISTRICT, RAJASTHAN, INDIA.

The concentrations of 238U and 232Th have been determined in drinking water samples collected from the Sikar district of Rajasthan State, India. The samples have been analysed by using high-resolution inductively coupled plasma mass spectrometry. 238U content in water samples ranged from 8.20 to 202.63 µg l-1 and 232Th content ranged from 0.57 to 1.46 µg l-1 The measured 238U content in 25 % of the analysed samples exceeded the World Health Organization (WHO) and United States Environmental Protection Agency drinking water guidelines of 30 µg l-1 and 12.5 % of the samples exceeded the 60 µg l-1 Indian maximum acceptable concentration recommended by the Atomic Energy Regulatory Board, India. The annual effective doses (µSv y-1) due to ingestion of 238U and 232Th for different age groups were also calculated. The results compared with the recommended value reported by the WHO.

Assessment of natural radioactivity levels and associated dose rates in soil samples from Northern Rajasthan, India.

The analysis of naturally occurring radionuclides ((226)Ra, (232)Th and (40)K) has been carried out in 40 soil samples collected from four districts of the Northern Rajasthan, India using gamma-ray spectrometry with an NaI(Tl) detector. The activity concentrations of the samples range from 38±9 to 65±11 Bq kg(-1) with a mean value of 52 Bq kg(-1) for (226)Ra, from 8±8 to 32±9 Bq kg(-1) with a mean value of 19 Bq kg(-1) for (232)Th and from 929±185 to 1894±249 Bq kg(-1) with a mean value of 1627 Bq kg(-1) for (40)K. The measured activity concentration of (226)Ra and (40)K in soil was higher and for (232)Th was lower than the worldwide range. Radium equivalent activities were calculated for the soil samples to assess the radiation hazards arising due to the use of these soils in the construction of buildings. The calculated average radium equivalent activity was 205±20 Bq kg(-1), which is less than the recommended limit of 370 Bq kg(-1) by the Organization for Economic Cooperation and Development. The total absorbed dose rate calculated from the activity concentration of (226)Ra, (232)Th and (40)K ranges from 77 to 123 nGy h(-1) with an average value of 103 nGy h(-1). The mean external (Hex) and internal hazard indices (Hin) for the area under study were determined to be 0.55 and 0.69, respectively. The corresponding average annual effective dose was found to be 0.63 mSv.

Uranium estimation in drinking water samples from some areas of Punjab and Himachal Pradesh, India using ICP-MS.

The uranium concentration in drinking water samples collected from areas of Punjab and Himachal Pradesh has been measured using inductively coupled plasma mass spectrometry. The sources of water comprise hand pumps and tube wells. The uranium concentration lies in the range of 1.24-45.42 µg l(-1) with a mean value of 14.91 µg l(-1) in drinking water samples from Punjab and 0.56-10.11 µg l(-1) with a mean value of 2.17 µg l(-1) in Himachal Pradesh. The measured uranium content in 4 % water samples from Punjab has been found to be higher than the limit of 30 µg l(-1) recommended by the World Health Organization (WHO) and US Environmental Protection Agency. However, the uranium concentration in all the water samples from Himachal Pradesh is well below the recommended limit. The annual effective dose associated with drinking water due to uranium concentration is estimated from its annual intake using dosimetric information based on International Commission on Radiological Protection 72. The resulting value of the annual effective dose from drinking water sources is in the range of 0.33-37.78 µSv, which is well within the limit of 100 µSv recommended by the WHO.

Determination of 222RN level in groundwater using a Rad7 detector in the Bathinda district of Punjab, India.

Radon gas is a significant health threat linked to thousands of preventable deaths each year. In this paper, radon activity concentration is measured in 260 groundwater samples collected from 65 villages in the Bathinda district of Punjab State, India, using Rad7, an electronic radon detector (Durridge Co., USA). The radon concentration varies from 0.9 ± 0.2 to 5.1 ± 0.3 Bq l(-1) with a mean value of 2.63 Bq l(-1). The recorded values of radon concentration in groundwater are within the safe limit of 11 Bq l(-1) recommended by the US Environmental Protection Agency. The annual effective dose in stomach and lungs per person is also evaluated in this research. The estimated total annual effective dose of adults ranged from 8.82 to 49.98 µSv y(-1). The total annual effective dose from all locations of the studied area is found to be within the safe limit (0.1 mSv y(-1)), recommended by World Health Organisation and EU Council.

Indoor radon measurements in the dwellings of Punjab and Himachal Pradesh, India.

The measurement of indoor radon concentrations were performed in the dwellings of the Punjab and Himachal Pradesh, India by using LR-115 type II Solid-State Nuclear Track Detectors in the bare mode. The annual average indoor radon concentrations in the dwellings are found to vary from 114 to 400 Bq m(-3) with an average of 194 Bq m(-3). In ∼22 % of the dwellings the indoor radon activity concentration values lies in the range of action level (200-300 Bq m(-3)) and in ∼11 % of the dwellings above the upper limit of action level recommended by the International Commission on Radiological Protection (ICRP). The annual effective dose (AED) varies from 2.88 to 10.08 mSv with an average of 4.88 mSv. In most of the villages, the AED lies in the range of action level (3-10 mSv) recommended by the ICRP. The seasonal variation in indoor radon reveals the maximum values in winter and minimum in summer. The winter/summer ratio of indoor radon ranges from 1.15 to 1.62 with an average of 1.31. Analysis of ventilation conditions reveal that the indoor radon concentration values are more in poorly ventilated dwellings compared with the well-ventilated ones.

Analysis of uranium concentration in drinking water samples using ICPMS.

Uranium concentration in drinking water samples collected from some areas of Northern Rajasthan has been measured using inductively coupled plasma mass spectrometry. The water samples were taken from hand pumps. The uranium concentration in water samples varies from 2.54-133.0 µg L with a mean value of 38.48 µg L. The uranium concentration in most of the drinking water samples exceeds the safe limit (30 µg L) recommended by the World Health Organization. The annual effective dose associated with drinking water due to uranium concentration is estimated from its annual intake using dosimetric information based on ICRP 72. The resulting value of the annual effective dose from drinking water sources is in the range of 2.11-110.45 µSv. The annual effective dose in one of the samples was found to be greater than WHO-recommended level of 100 µSv y.

Radon monitoring in groundwater samples from some areas of northern Rajasthan, India, using a RAD7 detector.

Radon monitoring has been increasingly conducted worldwide because of the hazardous effects of radon on the health of human beings. In the present research, groundwater samples were taken from hand pumps at different areas of the districts of SriGanganagar, Hanumangarh, Sikar and Churu in northern Rajasthan. RAD7, an electronic radon detector (Durridge co., USA), was used to estimate the radon concentration in groundwater used for drinking. Radon concentration in the groundwater ranged from 0.5 ± 0.3 Bq l(-1) (Chimanpura) to 85.7±4.9 Bq l(-1)(Khandela) with an average value of 9.03±1.03 Bq l(-1). In 89 % of the samples, radon concentration is well below the allowed maximum contamination level (MCL) of radon concentration in water of 11 Bq l(-1), proposed by US Environmental Protection Agency (USEPA). Only in 11 % of the samples, the recorded values were found to be higher than MCL proposed by USEPA and only in 5 % of the samples, the recorded values were found to be higher than the values between 4 and 40 Bq l(-1) suggested for radon concentration in water for human consumption by the United Nations Scientific Committee on the effect of Atomic Radiation (UNSCEAR). The annual effective dose in stomach and lungs per person was also evaluated in this research. The estimated total annual effective dose of adults ranged from 1.34 to 229.68 µSv y(-1). The total annual effective dose from three locations of the studied area was found to be greater than the safe limit (0.1 mSv y(-1)) recommended by World Health Organization and EU Council.