Ganesh Prasad - Academia.edu (original) (raw)

Papers by Ganesh Prasad

Radiation protection dosimetry, Jan 29, 2016

Long-term measurements of indoor radon, thoron and their progeny concentrations have been carried... more Long-term measurements of indoor radon, thoron and their progeny concentrations have been carried out in dwellings of Yamuna and Tons Valleys of Uttarkashi, Garhwal Himalaya to investigate the health risk associated with inhalation of radon, thoron and progeny. The experimentally determined values of radon, thoron and progeny concentrations were used to estimate the annual inhalation doses and annual effective doses. The annual inhalation dose has been found to vary from 0.8 to 3.9 mSv y(-1)with an average of 1.8 mSv y(-1) The annual effective dose from the exposure to radon and its progeny in the study area has been found to vary from 0.1 to 2.4 mSv with an average of 1.2±0.6 mSv. Similarly, the annual effective dose due to thoron and its progeny has been found to vary from 0.2 to 1.5 mSv with an average of 0.6±0.4. The measurement techniques and results obtained are discussed in detail.

Indian Journal of Physics, 2009

Radon was measured in soil-gas and groundwater in the Budhakedar area of Tehri Garhwal, India in ... more Radon was measured in soil-gas and groundwater in the Budhakedar area of Tehri Garhwal, India in summer and winter to obtain the seasonal variation and its correlation with radon exhalation rate. The environmental surface gamma dose rate was also measured in the same area. The radon exhalation rate in the soil sample collected from different geological unit of Budhakedar area was measured using plastic track detector (LR-115 type II) technique. The variation in the radon concentration in soil-gas was found to vary from 1098 to 31,776 Bq.m-3 with an average of 7456 Bq.m-3 in summer season and 3501 to 42883 Bq.m-3 with an average of 17148 Bq.m-3 in winter season. In groundwater, it was found to vary from 8 to 3047 Bq.l-1 with an average value 510 Bq.l-1 in summer and 26 to 2311 Bq.l-1 with an average value 433 Bq.L-1 in winter. Surface gamma dose rate in the study area varied from 32.4 to 83.6 mR.h-1 with an overall mean of 58.7 mR.h-1 in summer and 34.6 to 79.3 mR.h-1 with an average value 58.2 mR.h-1 in winter. Radon exhalation rate from collected soil samples was found to vary from 0.1 × 10-5 to 5.7 × 10-5 Bq.kg-1 .h-1 with an average of 1.5 × 10-5 Bq.kg-1 .h-1 in summer season and 1.7 × 10-5 to 9.6 × 10-5 Bq.kg-1 .h-1 with an average of 5.5 × 10-5 Bq.kg-1 .h-1. A weak negative correlation was observed between radon exhalation rate from soil and radon concentration in the soil. Radon exhalation rate from the soil was also not found to be correlated with the gamma dose rate, while it shows a positive correlation with radon concentration in water in summer season. Inter-correlations among various parameters are discussed in detail.

Indian Journal of Physics, 2009

... Prot. 12 36 (1989) [3] MR Menon, UC Mishra, BY Lalit, VK Shukla and TV Ramachandran Uranium, ... more ... Prot. 12 36 (1989) [3] MR Menon, UC Mishra, BY Lalit, VK Shukla and TV Ramachandran Uranium, thorium, and potassium in Indian rocks and ores. ... Page 6. GS Gusain, Manjari Badoni, Ganesh Prasad, Yogesh Prasad, TV Ramachandran and RC Ramola ...

Nuclear Technology and Radiation Protection, 2010

The components of the effective dose through inhalation from radon and its progeny are important ... more The components of the effective dose through inhalation from radon and its progeny are important for human health since they contribute to more than 50% of the total radiation dose from natural sources. As a consequence, radon has been identified as the second leading cause of lung cancer after smoking. Radon and its short lived decay products (218Po, 214Pb, 214Bi, 214Po) present in dwellings are a radiation hazard, particularly if such sources are concentrated in the enclosed areas like poorly ventilated houses and underground mines. The indoor radon, thoron, and progeny concentrations were measured in a small hilly town of Budhakedar and the surrounding area of Tehri Garhwal, India, by using LR-115 Type II plastic track detector in a twin cup radon dosimeter. The concentrations of radon progeny were measured as the highest in winter and the lowest in summer while the thoron progeny concentration was found maximum in rainy season and minimum in autumn. The annual exposure to the po...

Radiation Measurements, 2009

The assessment of radiological risk related to inhalation of radon and radon progeny is based mai... more The assessment of radiological risk related to inhalation of radon and radon progeny is based mainly on the integrated measurement of radon in both indoor and outdoor environments. The exhalation of radon from the earth crust and building materials forms the main source of radon in indoor environment. In this comparative study, the indoor radon level was measured using twin cup dosimeter in different dwellings of Garhwal Himalayas. Soil samples were collected simultaneously from different geological formations of the same area for laboratory measurement of radon exhalations rate. The radon exhalation rate was measured in the laboratory using LR-115 type II plastic track detectors. The indoor radon concentrations in this study area were found to vary from 13 AE 3 Bq/m 3 to 178 AE 8 Bq/m 3 with an average of 61 AE 5 Bq/m 3 while thoron concentration was found to vary 9 AE 2 Bq/m 3 to 94 AE 6 Bq/m 3 with an average of 33 AE 3 Bq/m 3. The radon exhalation rate was found to vary from (0.43 AE 0.05) Â 10 À5 Bq kg À1 h À1 to (20.10 AE 0.11) Â 10 À5 Bq kg À1 h À1 with an average of (1.95 AE 0.10) Â 10 À5 Bq kg À1 h À1. The detail significance of this study is discussed in radiation protection point of view.

Radiation Measurements, 2008

Environmental radiation exists as a consequence of cosmic, terrestrial and man made sources. Terr... more Environmental radiation exists as a consequence of cosmic, terrestrial and man made sources. Terrestrial radiation are emitted from natural radionuclide present in varying amounts in all types of soils, rocks, air, water and other environmental materials; radon is emitted from the soil surface, although secondary contributors include the oceans, natural gas, geothermal fluids, volcanic gases, ventilation from caves and mines, and combustion of coal. Radon and thoron levels were measured in soil-gas, ground water and indoor air in Budhakedar area of Tehri Garhwal, India. Radon concentrations in soil and groundwater of the Budhakedar area were found to vary from 1.10 ± 0.29 to 31.8 ± 1.6 kBq/m 3 with an average value 7.46 ± 0.69 kBq/m 3 and 8 ± 1 Bq/l to 3.05 ± 0.02 kBq/l with mean value 0.51 ± 0.01 kBq/l, respectively. Measurement of indoor radon, thoron and their daughter products were also measured in the houses of the same area for four different seasons (autumn, winter, summer and rainy) using LR-115 plastic track detectors. The detector is fixed in a twin chamber radon dosimeter, which can record the values of radon, thoron and their decay products separately. The film fixed in bare mode holder gives the concentrations of radon, thoron and their progeny while the films fixed inside the cup with filter and membrane modes give the concentrations of radon/thoron gases and of pure radon gas, respectively. Detailed analysis of the effects of seasonal variation on radon, thoron and their decay products inside the houses are reported in this paper.

Radiation Measurements, 2008

Atmospheric Environment, 2008

In most of the epidemiological studies contemporary radon measurements have been used as surrogat... more In most of the epidemiological studies contemporary radon measurements have been used as surrogates for radon concentrations in past decades even though changes in radon levels and residence may have occurred. Short-lived radon progeny may deposit on available surfaces in dwellings thus giving rise over time to a build up of long-lived progeny. Airborne radon decay products can be deposited and implanted through alpha recoil into the glass surfaces. On glass surface, activities of 210 Po may arise as a result of the decay of recoil implanted activity following the alpha decay of surface deposited 218 Po or 214 Po. Measurement of 210 Po implanted on a household glass is a method that can be employed to retrospectively determine the historic level of radon in dwellings. This method is based on the assumption that levels of recoil implanted 210 Po in the glass provide a measure of time integrated radon concentration in the environment in which the glass has been located. The surface deposited activity of the radon progenies, which then become implanted in the glass by alpha recoil, is believed to reflect past exposure to airborne activity. Such retrospective measurements on glass are valuable in estimating the human dose derived from radon during the time of exposure. In this paper an account is given of the principles and some field applications of a retrospective technique, using the alpha track detectors, CR-39 and LR-115, to measure 210 Po implanted in glass surfaces (surface traps). By using this CR-LR difference technique, the cumulative radon exposure in a dwelling in past decades may be estimated. This method provides reliable radon exposure data as a support to epidemiological studies concerning the health effects of radon exposure in the living environment.

Applied Radiation and Isotopes, 2011

The indoor radon concentration was estimated based on the radon flux in soil and groundwater. The... more The indoor radon concentration was estimated based on the radon flux in soil and groundwater. The indoor radon concentration in Budhakedar area of Garhwal Himalaya, India is estimated to be 3.0-131.4 Bq/m(3) in summer and 4.6-92.4 Bq/m(3) in winter. Based on the available data from study area, the calculated value of diffusion coefficient for the soil ranges from 0.1×10(-2) to 3.0×10(-2)cm(2) s(-1) in the summer season and 0.1×10(-2) to 0.4×10(-2)cm(2) s(-1) in the winter season. The calculated value of diffusion flux in the study area is found to vary from 0.1×10(-2) to 16.1×10(-2)Bq m(-2) s(-1) in summer season and 0.1×10(-2)-12.2×10(-2)Bq m(-2) s(-1) in winter season. The formulation was tested by comparing the results of radon values from two different seasons of a year.

Radiation protection dosimetry, Jan 29, 2016

Long-term measurements of indoor radon, thoron and their progeny concentrations have been carried... more Long-term measurements of indoor radon, thoron and their progeny concentrations have been carried out in dwellings of Yamuna and Tons Valleys of Uttarkashi, Garhwal Himalaya to investigate the health risk associated with inhalation of radon, thoron and progeny. The experimentally determined values of radon, thoron and progeny concentrations were used to estimate the annual inhalation doses and annual effective doses. The annual inhalation dose has been found to vary from 0.8 to 3.9 mSv y(-1)with an average of 1.8 mSv y(-1) The annual effective dose from the exposure to radon and its progeny in the study area has been found to vary from 0.1 to 2.4 mSv with an average of 1.2±0.6 mSv. Similarly, the annual effective dose due to thoron and its progeny has been found to vary from 0.2 to 1.5 mSv with an average of 0.6±0.4. The measurement techniques and results obtained are discussed in detail.

Indian Journal of Physics, 2009

Radon was measured in soil-gas and groundwater in the Budhakedar area of Tehri Garhwal, India in ... more Radon was measured in soil-gas and groundwater in the Budhakedar area of Tehri Garhwal, India in summer and winter to obtain the seasonal variation and its correlation with radon exhalation rate. The environmental surface gamma dose rate was also measured in the same area. The radon exhalation rate in the soil sample collected from different geological unit of Budhakedar area was measured using plastic track detector (LR-115 type II) technique. The variation in the radon concentration in soil-gas was found to vary from 1098 to 31,776 Bq.m-3 with an average of 7456 Bq.m-3 in summer season and 3501 to 42883 Bq.m-3 with an average of 17148 Bq.m-3 in winter season. In groundwater, it was found to vary from 8 to 3047 Bq.l-1 with an average value 510 Bq.l-1 in summer and 26 to 2311 Bq.l-1 with an average value 433 Bq.L-1 in winter. Surface gamma dose rate in the study area varied from 32.4 to 83.6 mR.h-1 with an overall mean of 58.7 mR.h-1 in summer and 34.6 to 79.3 mR.h-1 with an average value 58.2 mR.h-1 in winter. Radon exhalation rate from collected soil samples was found to vary from 0.1 × 10-5 to 5.7 × 10-5 Bq.kg-1 .h-1 with an average of 1.5 × 10-5 Bq.kg-1 .h-1 in summer season and 1.7 × 10-5 to 9.6 × 10-5 Bq.kg-1 .h-1 with an average of 5.5 × 10-5 Bq.kg-1 .h-1. A weak negative correlation was observed between radon exhalation rate from soil and radon concentration in the soil. Radon exhalation rate from the soil was also not found to be correlated with the gamma dose rate, while it shows a positive correlation with radon concentration in water in summer season. Inter-correlations among various parameters are discussed in detail.

Indian Journal of Physics, 2009

... Prot. 12 36 (1989) [3] MR Menon, UC Mishra, BY Lalit, VK Shukla and TV Ramachandran Uranium, ... more ... Prot. 12 36 (1989) [3] MR Menon, UC Mishra, BY Lalit, VK Shukla and TV Ramachandran Uranium, thorium, and potassium in Indian rocks and ores. ... Page 6. GS Gusain, Manjari Badoni, Ganesh Prasad, Yogesh Prasad, TV Ramachandran and RC Ramola ...

Nuclear Technology and Radiation Protection, 2010

The components of the effective dose through inhalation from radon and its progeny are important ... more The components of the effective dose through inhalation from radon and its progeny are important for human health since they contribute to more than 50% of the total radiation dose from natural sources. As a consequence, radon has been identified as the second leading cause of lung cancer after smoking. Radon and its short lived decay products (218Po, 214Pb, 214Bi, 214Po) present in dwellings are a radiation hazard, particularly if such sources are concentrated in the enclosed areas like poorly ventilated houses and underground mines. The indoor radon, thoron, and progeny concentrations were measured in a small hilly town of Budhakedar and the surrounding area of Tehri Garhwal, India, by using LR-115 Type II plastic track detector in a twin cup radon dosimeter. The concentrations of radon progeny were measured as the highest in winter and the lowest in summer while the thoron progeny concentration was found maximum in rainy season and minimum in autumn. The annual exposure to the po...

Radiation Measurements, 2009

The assessment of radiological risk related to inhalation of radon and radon progeny is based mai... more The assessment of radiological risk related to inhalation of radon and radon progeny is based mainly on the integrated measurement of radon in both indoor and outdoor environments. The exhalation of radon from the earth crust and building materials forms the main source of radon in indoor environment. In this comparative study, the indoor radon level was measured using twin cup dosimeter in different dwellings of Garhwal Himalayas. Soil samples were collected simultaneously from different geological formations of the same area for laboratory measurement of radon exhalations rate. The radon exhalation rate was measured in the laboratory using LR-115 type II plastic track detectors. The indoor radon concentrations in this study area were found to vary from 13 AE 3 Bq/m 3 to 178 AE 8 Bq/m 3 with an average of 61 AE 5 Bq/m 3 while thoron concentration was found to vary 9 AE 2 Bq/m 3 to 94 AE 6 Bq/m 3 with an average of 33 AE 3 Bq/m 3. The radon exhalation rate was found to vary from (0.43 AE 0.05) Â 10 À5 Bq kg À1 h À1 to (20.10 AE 0.11) Â 10 À5 Bq kg À1 h À1 with an average of (1.95 AE 0.10) Â 10 À5 Bq kg À1 h À1. The detail significance of this study is discussed in radiation protection point of view.

Radiation Measurements, 2008

Environmental radiation exists as a consequence of cosmic, terrestrial and man made sources. Terr... more Environmental radiation exists as a consequence of cosmic, terrestrial and man made sources. Terrestrial radiation are emitted from natural radionuclide present in varying amounts in all types of soils, rocks, air, water and other environmental materials; radon is emitted from the soil surface, although secondary contributors include the oceans, natural gas, geothermal fluids, volcanic gases, ventilation from caves and mines, and combustion of coal. Radon and thoron levels were measured in soil-gas, ground water and indoor air in Budhakedar area of Tehri Garhwal, India. Radon concentrations in soil and groundwater of the Budhakedar area were found to vary from 1.10 ± 0.29 to 31.8 ± 1.6 kBq/m 3 with an average value 7.46 ± 0.69 kBq/m 3 and 8 ± 1 Bq/l to 3.05 ± 0.02 kBq/l with mean value 0.51 ± 0.01 kBq/l, respectively. Measurement of indoor radon, thoron and their daughter products were also measured in the houses of the same area for four different seasons (autumn, winter, summer and rainy) using LR-115 plastic track detectors. The detector is fixed in a twin chamber radon dosimeter, which can record the values of radon, thoron and their decay products separately. The film fixed in bare mode holder gives the concentrations of radon, thoron and their progeny while the films fixed inside the cup with filter and membrane modes give the concentrations of radon/thoron gases and of pure radon gas, respectively. Detailed analysis of the effects of seasonal variation on radon, thoron and their decay products inside the houses are reported in this paper.

Radiation Measurements, 2008

Atmospheric Environment, 2008

In most of the epidemiological studies contemporary radon measurements have been used as surrogat... more In most of the epidemiological studies contemporary radon measurements have been used as surrogates for radon concentrations in past decades even though changes in radon levels and residence may have occurred. Short-lived radon progeny may deposit on available surfaces in dwellings thus giving rise over time to a build up of long-lived progeny. Airborne radon decay products can be deposited and implanted through alpha recoil into the glass surfaces. On glass surface, activities of 210 Po may arise as a result of the decay of recoil implanted activity following the alpha decay of surface deposited 218 Po or 214 Po. Measurement of 210 Po implanted on a household glass is a method that can be employed to retrospectively determine the historic level of radon in dwellings. This method is based on the assumption that levels of recoil implanted 210 Po in the glass provide a measure of time integrated radon concentration in the environment in which the glass has been located. The surface deposited activity of the radon progenies, which then become implanted in the glass by alpha recoil, is believed to reflect past exposure to airborne activity. Such retrospective measurements on glass are valuable in estimating the human dose derived from radon during the time of exposure. In this paper an account is given of the principles and some field applications of a retrospective technique, using the alpha track detectors, CR-39 and LR-115, to measure 210 Po implanted in glass surfaces (surface traps). By using this CR-LR difference technique, the cumulative radon exposure in a dwelling in past decades may be estimated. This method provides reliable radon exposure data as a support to epidemiological studies concerning the health effects of radon exposure in the living environment.

Applied Radiation and Isotopes, 2011

The indoor radon concentration was estimated based on the radon flux in soil and groundwater. The... more The indoor radon concentration was estimated based on the radon flux in soil and groundwater. The indoor radon concentration in Budhakedar area of Garhwal Himalaya, India is estimated to be 3.0-131.4 Bq/m(3) in summer and 4.6-92.4 Bq/m(3) in winter. Based on the available data from study area, the calculated value of diffusion coefficient for the soil ranges from 0.1×10(-2) to 3.0×10(-2)cm(2) s(-1) in the summer season and 0.1×10(-2) to 0.4×10(-2)cm(2) s(-1) in the winter season. The calculated value of diffusion flux in the study area is found to vary from 0.1×10(-2) to 16.1×10(-2)Bq m(-2) s(-1) in summer season and 0.1×10(-2)-12.2×10(-2)Bq m(-2) s(-1) in winter season. The formulation was tested by comparing the results of radon values from two different seasons of a year.