Studies on the dependence of natural radioactivity on clay minerals of soils in Davanagere district of Karnataka, India

Radiation hazard assessment of radioactive elements 232Th, 226Ra, and 40K in local and imported sugar in Iraqi Kurdistan

Natural radioactivity is receiving a lot of attention worldwide due to its essential role in human health. Sugar is a generic term for sweet, soluble carbohydrates, many of which find their way into food. Therefore, measuring natural radioactivity is critical as it has a direct impact on human safety. This research analyzed natural radionuclide activity levels in 22 samples of commonly consumed sugar from the Kurdistan Region of Iraq. High-purity germanium (HPGe) detectors are used in gamma-ray spectrometers. Measurements in this study showed that 226Ra activity concentrations ranged from below minimum detectable activity (BMDA) to 5.16 ± 2.55 Bq kg-1 with an average value of 0.80 ± 0.15 Bq kg-1. In contrast, 232Th radionuclide activity concentrations ranged from BMDA to 3.11 ± 1.67 Bq kg-1 with an average value of 0.51 ± 0.10 Bq kg-1. Also, the activity concentration of 40K ranged from BMDA to 30.71 ± 10.77 Bq kg-1 with a mean of 6.44 ± 2.54 Bq kg-1. Based on these results, a radiation risk index associated with sugar intake was calculated. It was verified that the radiation exposure due to sugar consumption in the Kurdistan Region of Iraq was below the permissible level of 290 μSv y-1, and did not pose a radiation risk to public health.

Effect of gamma dose rate on the public from soil samples collected from industrial areas of Tamil Nadu

The present work is the first and foremost radiological study of soil samples collected from industrial estates in Tamil Nadu. The magnetic susceptibility measurement revealed that 74.19% of the samples have medium %χFD, which denotes a commixture of coarser grains or the SP grains with a size of <0.005 μm. The range of measured activities of 210Po and 210Pb were 3 ± 0.3-38 ± 2.6 Bq kg-1 and 16 ± 1.5-48 ± 2.9 Bq kg-1. The mean activity concentrations of 238U (33 Bq kg-1) and 40K (467 Bq kg-1) marginally exceeded the Indian recommended values of 28.67 and 400 Bq kg-1, respectively, whereas 232Th (47 Bq kg-1) did not exceed 63.83 Bq kg-1. The 238U and 232Th are the significant contributors to the production of radiogenic heat in the study area. Pearson correlation analysis confirmed the prime role of 232Th in radiation hazards and the insignificant relation between magnetic minerals and natural radioactivity.

Analysis of internal gamma-ray dose to the public from brick as building material in Tamil Nadu, India

Natural radioactivity due to 238U, 232Th and 40K in brick samples from Tamil Nadu was determined using gamma-ray spectrometry. The mean activity concentrations of 238U, 232Th and 40K, 69 ± 6, 62 ± 6 and 462 ± 23 Bq kg-1, are slightly greater than the world recommended limits of 35, 45 and 420 Bq kg-1, respectively, and they are compared with a similar work carried out across the world. The radiological parameters such as radium equivalent activity, Raeq (193 ± 17 Bq kg-1), internal hazard index, Hin (0.71 ± 0.06), and activity utilisation index, AUI (1.43 ± 0.13), was lower, whilst absorbed dose rate, DRin (89 ± 8 nGy h-1), annual effective dose equivalent, AEDEin (0.43 ± 0.04 mSv y-1), and excess lifetime cancer risk, ELCRin (1.52 ± 0.13 mSv y-1), are slightly greater than the world's recommended limit. Bi-variate statistical analysis was performed to corroborate the relationship between radionuclides and radiological hazards.

A review on radionuclide pollution in global soils with environmental and health hazards evaluation

Human populations are being exposed to a wide spectrum of radiation from soils as a result of the availability of radiation sources. Assessing the ecological and health effects of radionuclides in soils is crucial to support the optimal soil management practices but large-scale studies are limited. This study compiled data on radionuclides (226Ra, 232Th, 40K, 238U, and 137Cs) in soils located across the world (44 countries and 159 places) between 2008 and 2022 and applied radiological hazards indices and several multivariate statistical approaches. The average activity concentration (Bq/kg) of 226Ra, 232Th, 40K, 238U, and 137Cs were 408.56, 144.80, 508.78, 532.78, and 83.12, respectively, whereas 226Ra, 232Th, 40K, and 238U exceeded the standard limits. The principal component analysis explained more than 91% of variation in soils. Based on the geoaccumulation index, 40K posed moderately to heavy contamination whereas 238U and 226Ra posed moderate contamination in soils. Moreover, the mean values of radiological hazards evaluation such as radium equivalent activity (487.17 Bq/kg), external radiation hazard indices (1.32), internal hazard indices (2.15), absorbed dose rate (247.86 nGyh-1), annual effective dose rate (1.82 mSvy-1), activity utilization index (4.54) and excess lifetime cancer risk (63.84 × 10-4) were higher than recommended limit suggesting significant radiological risks in study region soils. The findings indicated that the study area soils were contaminated by radionuclides and unsafe for hazards in terms of the health risks linked with studied radioactive contents. The study is valuable for mapping radioactivity across the globe to determine the level of radioactivity hazards.

Distributions and Risk Assessment of the Natural Radionuclides in the Soil of Shoubra El Kheima, South Nile Delta, Egypt

Due to heightening concern about radiation hazards protection, activity concentrations of 226Ra, 232Th, 40K in forty soil samples collected from Shoubra El Kheima in the South Nile Delta were measured using gamma-ray spectrometry. The mean activity concentrations of 226Ra and 40K were higher in 20% of the considered samples than the world average values. A comprehensive comparison with up-to-date data was carried out. Spatial distribution maps of the measured radionuclides and radiological parameters were generated. The distributions of natural radionuclides were influenced by the soil organic matter, clay content, and scavenger metals oxides, as well as differences in the physical and chemical attributes and solubility of these radionuclides. The results revealed that industrial activity and agricultural practices in the study area caused an incremental increase in 226Ra and 40K activity concentrations. It can be deduced that although there are intensive industrial activities in this area, the natural radiation that comes from the soil is normal and does not pose a significant radiological hazard to the public. The natural radioactivity of soil in this area needs to be monitored periodically to prevent unnecessary radiation exposure to inhabitants.