Natural Radioactivity of Raw Materials and Products in the Cement Industry

et al. 2010

Water Air Soil Pollut

The analysis of gamma emitters natural radionuclides, i.e., 226 Ra, 232 Th, and 40 K, has been carried out in soil, vegetation, vegetable, and water samples collected from some Northern area of Pakistan, using gamma-ray spectrometry. The γ-ray spectrometry was carried out using high-purity Germanium detector coupled with a computer-based high-resolution multi-channel analyzer. The activity concentrations in soil ranges from 24.7 to 78.5 Bq kg −1 , 21.7 to 75.3 Bqkg −1 , and 298.5 to 570.8 Bq kg −1 for 226 Ra, 232 Th, and 40 K with the mean value of 42.1, 43.3, 9.5, and 418.3 Bqkg −1 , respectively. In the present analysis, 40 K was the major radionuclide present in soil, vegetation, fruit, and vegetable samples. The concentration of 40 K in vegetation sample varied from 646.6 to 869.6 Bqkg −1 on dry weight basis. However, the concentration of 40 K in fruit and vegetable samples varied from 34.0 to 123.3 Bqkg −1 on fresh weight basis. In vegetation samples, along with 40 K, 226 Ra, and 232 Th were also present in small amount. The transfer factors of these radionuclides from soil to vegetation, fruit, and vegetable were also studied. The transfer factors were found in the order: 40 K> 232 Th≈ 226 Ra. The analysis of water samples showed activity concentrations values for all radionuclides below detection limit. The internal and external hazard indices were measured and found less than the safe limit of unity. The mean value of outdoor and indoor absorbed dose rate in air was found 64.61 and 77.54 nGyh −1 , respectively. The activity concentrations of radionuclides found in all samples during the current investigation were nominal. Therefore, they are not associated with any potential source of health hazard to the general public.

“…For the maximum value of H ex to be less than unity, the maximum value of Ra eq must be <370 Bqkg −1 . Internal hazard index (H in ) is given by (Gallyas and Torok 1984):…”

Section: Resultsmentioning

confidence: 99%

Measurement of Radionuclides and Gamma-Ray Dose Rate in Soil and Transfer of Radionuclides from Soil to Vegetation, Vegetable of Some Northern Area of Pakistan Using γ-Ray Spectrometry

et al. 2010

Water Air Soil Pollut

“…For the maximum value of H ex to be less than unity, the maximum value of Ra eq must be <370 Bq kg −1 .Internal hazard index (H in ) is given by (Gallyas and Torok 1984):…”

Section: Resultsmentioning

confidence: 99%

Assessment of Radionuclides, Trace Metals and Radionuclide Transfer from Soil to Food of Jhangar Valley (Pakistan) Using Gamma-Ray Spectrometry

Chaudhry

et al. 2010

Water Air Soil Pollut

The gamma spectrometric analysis of soil and essential foodstuffs, e.g., wheat, millet, potato, lentils and cauliflower, which form the main component of the daily diet of the local public, was carried out using high purity germanium (HpGe) detector coupled with a computer based high-resolution multichannel analyzer. The activity concentration in soil samples for 226 Ra, 232 Th and 40 K ranged from 30.0 Bq kg −1 to 81.2 Bq kg −1 , 31.4 Bq kg −1 to 78.25 Bq kg −1 and 308.8 Bq kg −1 to 2177.6 Bq kg −1 , with mean values of 56.2, 58.5 and 851.9 Bq kg −1 , respectively. The average activity measured for 226 Ra, 232 Th and 40 K in soil samples was found higher than the world average. The major radionuclide found in the food items studied was 40 K, while 226 Ra, 232 Th and 137 Cs were detected in very nominal amounts. The results clearly indicate that these radionuclides have no health hazard to human beings, as they are well below the annual limit of intake (ALI) for these radionuclides. The transfer factors of these radionuclides from soil to food were also studied. The mean transfer factors of 40 K, 226 Ra, 232 Th and 137 Cs from soil to food were estimated to be about 0.17, 0.07, 0.16 and 0.23, respectively. An artificial radionuclide, 137 Cs, was also present in detectable amount in all samples. The internal and external hazard indices were measured and had mean values of 0.70 and 0.55, respectively. Absorbed dose rates and effective dose have been determined in the present study. Concentration of trace metals, such as Cr, Pb, Ni and Zn, was also determined in the soil samples. The concentrations of radionuclides and trace metals found in these samples during the present study were nominal and do not pose any potential health hazard to the general public.

“…For the maximum value of H out , it is to be less than 1. The indoor hazard index (H in ) is given by [24]:…”

Section: Resultsmentioning

confidence: 99%

Measurement of radionuclides and absorbed dose rates in soil samples of Peshawar, Pakistan, using gamma ray spectrometry

Isotopes in Environmental and Health Studies

Zia

et al. 2012

The analysis of gamma-emitting radionuclides in nature, i.e. (226)Ra, (232)Th, (40)K and (137)Cs, has been carried out in soil samples collected from Peshawar University Campus and surrounding areas using a high purity germanium detector coupled with a computer-based high-resolution multichannel analyser. The activity concentrations in soil ranged from 30.20±0.65 to 61.90±0.95, 50.10±0.54 to 102.80±1.04, 373.60±4.56 to 1082±11.38 and 9.50±0.11 to 46.60±0.42 Bq kg(-1) for (226)Ra, (232)Th, (40)K and (137)Cs, with a mean value of 45±7.70, 67±12.50, 878±180 and 19±9.20 Bq kg(-1), respectively. The radium equivalent activity, internal and external hazard indices have mean values of 203.40±29.40 Bq kg(-1), 0.56 and 0.68, respectively. The mean values of outdoor and indoor absorbed dose rates in air and the annual effective dose equivalents were found to be 106.50 and 128 nGy h(-1) and 0.19 and 0.54 mSv y(-1), respectively. In the present study, (40)K was the major radionuclide present in soil samples. The presence of (137)Cs indicates that this area also received some fallout from the nuclear accident of the Chernobyl power plant in 1986. The activity concentrations of radionuclides found in soil samples during the current investigation were nominal. Therefore, they are not associated with any potential source of health hazard to the public.