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The estimated mean value of activity of radionuclides (226Ra, 232Th, and 40K) in the forest environment of Shankaraghatta are 11.52 ± 1.6, 19.94 ± 2.08 and 164.67 ± 3.2 Bq kg−1 for soil, and for building materials 48.53 ± 1.99, 63.20 ± 2.48 and 470.47 ± 6.59 Bq kg−1 respectively. The average indoor and outdoor Gamma Absorbed Dose rate and total Annual Effective Dose rate are less than the global average values. The forest ecosystem influenced in reducing the natural ambient gamma radiation levels. The constructions materials used for roads enhanced it. The entire measured hazard indices are far below the criterion limit of unity except pink granite and ceramic tiles contains higher activity of radionuclides. [ABSTRACT FROM AUTHOR]

This study reports the gamma absorbed dose rate (GADR) in 88 locations within five different geological regions of Uttara Kannada district. The measurements were made using a UR-705 environmental radiation dosimeter. The outdoor gamma absorbed dose rate varies from 44.5 to 220.0 nGy h–1 with the mean value of 78.0 nGy h–1, which is 1.3 times higher than the international average value of 59 nGy h–1. The indoor gamma absorbed dose rate varies from 57.3 to 242.5 nGy h–1 with an average of 90.0 nGy h–1, which is slightly higher than the world average of 84 nGy h–1 as suggested by UNSCEAR-2000. The estimated dose rate varies with the geological background and soil type. The total AEDE ranges from 0.3 to 1.38 mSv year–1 with an average of 0.53 mSv year–1. The average total AEDE is lower than the dose limit of 1 mSv year–1 for public, suggested by ICRP-1991. [ABSTRACT FROM AUTHOR]

This study assesses the ambient gamma dose rate and radon concentration in drinking water at different locations in few coastal taluks of Uttara Kannada district. The ambient gamma dose and 222Rn activity in drinking water has been estimated by using micro R survey meter and Emanometry technique respectively. The annual effective doses ranges from 0.39 to 0.82 mSvy−1 with a geometric mean value of 0.55 mSvy−1 and it is slightly higher than the world average value. 222Rn activity in drinking water vary from 3.34 ± 0.22 to 160.18 ± 1.84 Bql−1 with mean value of 25.07 ± 0.86 Bql−1. Annual average ingestion dose due to consuming water are well below the WHO and EC suggested action level of 100 µSvy−1. [ABSTRACT FROM AUTHOR]

This study presents the results of indoor and outdoor ambient gamma dose rates and radon concentration in groundwater at different locations of Koppa and Narasimharajapura taluks of Chikmagalur district, (13°40' north latitude and 75° 62' east longitudes). The total annual effective dose ranged between 0.67 mSv/y and 1.76 mSv/y with an average value of 1.16 mSv/y. The calculated total annual effective dose was found to be higher than the world average. The radon concentration in groundwater was analyzed using radon emanometry technique. The measured radon concentrations ranged from 3.96 Bq/l to 90.63 Bq/l with an average value of 35.34 Bq/l. This study reveals that 80% of drinking water samples have radon levels higher than the maximum contaminant level of 11 Bq/l recommended by the United States Environmental Protection Agency. All the recorded radon concentration values were found to be well below the action level of 100 Bq/l recommended by the World Health Organization. It is also found that the dose due to borewell water samples is higher compared to dose due to water from other sources such as hand pump, open well, and tap water. [ABSTRACT FROM AUTHOR]