The present study was conducted to investigate trace metal (Li, Be, B, Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As Se, Mo, Cd, Sb, Ba and Pb) concentrations of drinking water samples in northeast Rajasthan, India. Furthermore, the study aimed to ascertain carcinogenic and non-carcinogenic health risks of metals by ingestion and dermal absorption pathways to the local residents. Metal concentrations were analyzed by using high resolution inductively coupled plasma mass spectrometry and compared with permissible limits set by the Bureau of Indian Standards, United States Environmental Protection Agency and World Health Organization. The results indicate that the concentrations of Be, B, Al, Cr, Fe, Cu, Zn, As, Mo, Sb and Ba were lower than their respective permissible limits, whereas the concentrations of Mn, Ni, Se, Cd and Pb in some samples were higher than their permissible limits. The total hazard index (summing the hazard index through ingestion and dermal routes) at all the sampling sites exceeded or nearing unity, indicating the presence of non-carcinogenic health effects from ingestion of water and dermal contact with water. The results indicate that the total excess lifetime cancer risk (considering both ingestion and dermal exposure pathways) of metals exposure was in accordance to the acceptable lifetime risks for carcinogens in drinking water (10−6–10−4). Both carcinogenic and non-carcinogenic risks were mainly attributed to the ingestion pathways.

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 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.

No abstract

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.