Normal Background Radiation Research Articles

An Exposure to Natural Background Radiation in Eastern Nepal

Monitoring natural background radiation is important to locate the high background area. The objective of the work is to find the average background radiation in the Morang district and to observe the effects of cosmic radiation at high altitudes. In this study, background radiation was measured in 17 different municipalities of Morang with the help of a GM counter of model GMC-300E plus. The result showed that the annual effective dose of Morang was 0.24±0.02mSv/y and was below the recommended value of 1 mSv/y set by ICRP for public health. The radiation level was slightly higher in the hospital area. The frequency distribution indicates that there is a good fit of observed data with a known Gaussian distribution. The variation of background radiation with an altitude from 381 to 2550m showed an increasing trend. The best-fitted line depicted that background radiation increased by 16% with 1000m in altitude and it was slightly higher than the literature’s result of 10-12%. The comparative study of the present work showed that the effective dose was the least value in the Morang (0.24mSv/y) and the highest in the Pokhara Valley (0.81mSv/yr).

Measurements of natural radioactivity and evaluation of radiation hazard indices in soils around the Manyoni uranium deposit in Tanzania

Pre-mining natural radioactivity levels in soils over a 27.96 km2 site around the Manyoni Uranium Project in Tanzania were determined by a high purity germanium detector. The mean activity concentrations of 226Ra, 232Th, and 40K in soils were 227.43 ± 38.79 Bq/kg, 65.22 ± 3.70 Bq/kg, and 107.32 ± 23.07 Bq/kg, respectively. The average radium equivalent activity (Raeq), external hazard index (Hex), and internal hazard index (Hin) at these concentrations were 328.95 Bq/kg, 0.89, and 1.50, respectively. The mean absorbed dose rate in air at 1 m above the ground (Da) was 148.94 nGy/h, and the mean outdoor annual effective dose (Ed) was 0.18 mSv/y. Additionally, natural radioactivity levels in soils over a 0.71 km2 site, which is inside the 27.96 km2 site, which is prone to mine dust pollution above healthy levels, were also determined. The mean activity concentrations of 226Ra, 232Th, and 40K in the soils from this site were 380.4 ± 59.93 Bq/kg, 78.69 ± 8.99 Bq/kg, and 70.40 ± 7.91 Bq/kg, respectively. The corresponding means for Raeq, Hex, and Hin were 498.35 Bq/kg, 1.35, and 2.37, respectively. The mean Da and Ed were 226.21 nGy/h and 0.28 mSv/y, respectively. The average values of Ed at both sites were less than the public exposure limit of 1 mSv/y. This means that the sites have normal background radiation levels that do not endanger people's health when they engage in outdoor activities. When mining begins, the natural radioactivity levels obtained in this study, rather than national or global averages, can be used by mine owners or government agencies to assess the environmental effects of mining. Even after mining and during decommissioning, these baseline levels can also be used to measure how well the land has been restored.

Assessment of Threshold Dose of Thoron Inhalation and Its Biological Effects by Mimicking the Radiation Doses in Monazite Placer Deposits Corresponding to the Normal, Medium and Very High Natural Background Radiation Areas.

The dose contributed from thoron (220Rn) and its progeny has been neglected in the dose assessment because of its short half-life (t1/2 = 55.6s) and generally low concentrations. Recently, concentrations of 220Rn gas and its progeny were found to be pronounced in the traditional residential dwellings in China, on beaches of India and in other countries. Accordingly, we investigated the biological effects of thoron (220Rn) decay products in various mouse organs, succeeding inhalation of thoron gas in BALB/c mouse. We investigated the biological effects upon thoron inhalation on mouse organs with a focus on oxidative stress. These mice were divided into (4 random groups): sham inhalation, thoron inhalation for 1, 4 and 10days. Various tissues (lung, liver and kidney) were then collected after the time points and subjected to various biochemical analyses. Immediately after inhalation, mouse tissues were excised for gamma spectrometry and 72h post inhalation for biochemical assays. The gamma spectrometry counts and its subsequent calculation of the equivalent dose showed varied distribution in the lung, liver and kidney. Our results suggest that acute thoron inhalation showed a differential effect on the antioxidant function and exerted pathophysiological alterations via oxidative stress in organs at a higher dose. These findings suggested that thoron inhalation could alter the redox state in organs; however, its characteristics were dependent on the total redox system of the organs as well as the thoron concentration and inhalation time.

Soil radioactivity levels and radiation exposure to the population in Aswan and Abu Simbel areas, South of Egypt

Gamma-ray spectrometer and Lucas cell were used to evaluate the activity concentrations of 226Ra, 232Th, 40K, and 222Rn mass exhalation rates for 37 topsoil samples from different sites in Aswan city, Aswan-Abu Simbel highway, and Abu Simbel village, south of Egypt. The average activity concentration of 226Ra, 232Th, and 40K was 23.3 ± 1.7, 21.1 ± 1.2, and 283.4 ± 22.3; 21.2 ± 1.7, 15.2 ± 1.0, and 89.4 ± 10.5; 29.0 ± 2.2, 26.3 ± 1.5, and 79.5 ± 9.7 Bq kg−1 for soil from Aswan city; Aswan-Abu Simbel highway; and Abu Simbel village, respectively. Activity ratios for the studied radionuclides were calculated, and 232Th/226Ra ratios in most of the sampling sites were <1.1 (natural equilibrium ratio). The mass ratio of Th/K was computed, and the results showed the presence of three main types of clay minerals (montmorillonite, kaolinite, and heavy thorium-bearing minerals) in the studied areas. Radon measurements showed that soil from Aswan city has the highest average value of 222Rn mass exhalation rate (20.6 ± 1.7 mBq kg−1 h−1). The ambient dose equivalent rates were measured in situ using the portable survey meter, and the obtained values showed no significant differences between the studied areas. In general, the results indicate that the studied areas can be considered as areas with normal background radiation levels, and therefore the risks of exposure to natural radiation are minimal.

The Use of Computerized Tomography Scans in Elective Knee and Hip Arthroplasty-What Do They Tell Us and at What Risk?

The average background radiation exposure in the United States has nearly doubled over the previous quarter century, with almost all the increase derived from medical imaging. Nearly 2% of all cancers in the United States may be attributable to radiation from computerized tomography (CT) scans. Given the nondiagnostic nature of CT scans that are used in elective knee and hip arthroplasty today, special consideration should be given to the inherent risk of radiation exposure with routine use of this technology. Methods to decrease radiation exposure including modulating the settings of the CT machine and using alternative non-CT-based systems can decrease patient exposure to radiation from CT scans. The rapid evolution of CT technology in arthroplasty has allowed for expanded clinical applications, the benefits of which remain controversial.

The Effects of High Level Natural Radiation in Mamuju - Indonesia on the Immune System of Its Residents

The immune system is one of the most significant defenses against environmental insults including natural radiation. The purpose of this preliminary study was to assess the effects of high natural radiation to Mamuju residents, by focusing on immune-related blood cell counts (leukocytes, lymphocytes, monocytes, and granulocytes) and immunoglobulin E (IgE) level. The blood samples were collected from 18 adult residents in a high background radiation area (HBRA) while 18 residents in a normal background radiation area (NBRA) served as a control group. The blood components were measured by using the hematopoietic analyzer, and IgE immune biomarker was measured with ELISA (enzyme-linked immunosorbent assay) according to standard protocols. The data showed that the level of all blood cells, except for monocytes, of residents in HBRA was higher than that of NBRA. Statistical analysis revealed that there was no significant difference ( P &gt;0.05) in the blood cell counts and IgE level in both groups and their values were within normal limits. The level of IgE in HBRA was significantly higher than the control area ( P ≤0.05), as its IgE level in males compared to females in both residents. The relationship between IgE level and age were negative in these residents. From this study, it was concluded that long-term exposure to high radiation may affect the immune system as one of radiation adaptive response.

Shielding assessment in two computed tomography facilities in South-South Nigeria: How safe are the personnel and general public from ionizing radiation?

Objective: The aims of this study were to estimate the instantaneous dose rate(IDR) and annual dose rate (ADR) to radiation staff and the general public withinthe controlled and supervised areas, respectively, to determine the shieldingdesign goals (P) of the 2 CT facilities and to determine the average annual dose(AD) to radiographer/operator in the control console during CT scans. Materials and Methods: The equipment used in this study consisted of twonewly installed General Electric (GE) Revolution ACTs CT machines. Technicalparameters used were a thoracic/dorsal spine scan, which was rarely done in both facilities. A calibrated Inspector USB (S.E. International, Inc.) survey meter was positioned &lt; 50 cm from each barrier at various points to determine the average shielded air kerma Results: The average background radiation in the 2 facilities was 0.11 ?Sv/hr. The average ADR to the controlled and supervised areas in CT1 was 0.563±0.25 and 0.369±0.11 mSv/yr, respectively. Also, the average ADR to the controlled and supervised areas in CT2 were 0.410±0.28 and 0.354±0.04 mSv/yr, respectively. The average shielding design goal to the controlled and supervised areas for CT1 was 0.00898±0.0041 and 0.0059±0.0028 mSv/Week, respectively. Similarly, the average shielding design goal for the controlled and supervised areas for CT2 was 0.0066±0.0044 and 0.0057±0.0019 mSv/Week respectively. The estimated average AD to the operator in CT1 and CT2 was 2.5 and 1.3 ?Sv, respectively. Conclusion: The average ADR and shielding design goals in the controlled and supervised areas from both CTs were within acceptable limits for radiation staff and the public.

Shielding assessment in two computed tomography facilities in South-South Nigeria: How safe are the personnel and general public from ionizing radiation?

Objective: The aims of this study were to estimate the instantaneous dose rate(IDR) and annual dose rate (ADR) to radiation staff and the general public withinthe controlled and supervised areas, respectively, to determine the shieldingdesign goals (P) of the 2 CT facilities and to determine the average annual dose(AD) to radiographer/operator in the control console during CT scans. Materials and Methods: The equipment used in this study consisted of twonewly installed General Electric (GE) Revolution ACTs CT machines. Technicalparameters used were a thoracic/dorsal spine scan, which was rarely done in both facilities. A calibrated Inspector USB (S.E. International, Inc.) survey meter was positioned &lt; 50 cm from each barrier at various points to determine the average shielded air kerma Results: The average background radiation in the 2 facilities was 0.11 ?Sv/hr. The average ADR to the controlled and supervised areas in CT1 was 0.563±0.25 and 0.369±0.11 mSv/yr, respectively. Also, the average ADR to the controlled and supervised areas in CT2 were 0.410±0.28 and 0.354±0.04 mSv/yr, respectively. The average shielding design goal to the controlled and supervised areas for CT1 was 0.00898±0.0041 and 0.0059±0.0028 mSv/Week, respectively. Similarly, the average shielding design goal for the controlled and supervised areas for CT2 was 0.0066±0.0044 and 0.0057±0.0019 mSv/Week respectively. The estimated average AD to the operator in CT1 and CT2 was 2.5 and 1.3 ?Sv, respectively. Conclusion: The average ADR and shielding design goals in the controlled and supervised areas from both CTs were within acceptable limits for radiation staff and the public.

A Preliminary Appraisal of Radon Concentration in Groundwater from the High Background Radiation Area (HBRA) of Coastal Kerala

Abstract Parts of the coastal tracts of southern Kerala, India are among the well-known High Background Radiation Areas (HBRA) of the world, attributed to the presence of radionuclides in the monaziterich beach sand deposits. A comparative study of the radon concentrations in groundwater in the high and normal background radiation areas in the coastal tract has been taken up using analytical data of 24 ground water samples collected from tube wells of ranging in depth from 6.0 to 300.0 m. The radon concentration in the samples ranged from 0.88 to 25.80 Bq.L-1. The mean radon concentration in the study area, including those from the HBRA are within the maximum contamination levels of 300 pCi.L-1 (11.10 Bq.L-1) recommended by the United States Environmental Protection Agency except for a sample collected from Chavara. Groundwater from the high background radiation areas has significantly higher concentrations of radon ranging from 2.84 - 25.80 Bq.L-1 when compared to the normal background areas where the concentrations range from 0.86 - 7.46 Bq.L-1. Radon concentration does not show significant correlation with depth of sampled wells. The mean annual effective doses of ingestion and inhalation from water-borne radon, though comparatively higher in HBRA, are well below the average doses reported from all natural sources.

The effective dose due to scattered radiation at patients during primary osteosynthesis; a multicenter prospective observational study

ObjectivesDuring osteosynthesis of a fracture patients are exposed to the primary radiation of an X-ray image and scattered (secondary) radiation. The primary objective was to measure the amount of scattered radiation at the thyroid, breast tissue, and gonads of patients undergoing primary osteosynthesis of acute fractures. The secondary objective was to calculate the effective dose caused by scattered radiation. MethodsIn this multicenter prospective observational case series patients undergoing a primary osteosynthesis of an acute fracture of hand/wrist, shoulder, ankle, knee, or hip were included. Three dosimeters were attached to the patient at the level of the thyroid, breast and gonads. Scattered radiation doses were corrected for the average background radiation per hospital per day. ResultsA total of 205 patients were included between March 6, 2017 and June 18, 2018; 49 (24%) had a hand/wrist fracture, 37 (18%) a shoulder fracture, 47 (23%) an ankle fracture, 35 (17%) a knee fracture, and 37 (18%) a hip fracture. In 32–39% of all patients undergoing primary osteosynthesis effective scattered doses was detected. The highest measured median effective dose was 60.43 µSv (P25–P75 33.84–100.76) at the gonads during hip osteosynthesis. ConclusionsThe results of this study show that scattered radiation is detectable in a third of patients undergoing an osteosynthesis. However, both effective doses due to direct radiation and scattered radiation are low. Advances in knowledgeThis is the first study that presents that no radiation protection for patients undergoing an osteosynthesis is necessary.

GAMMA DOSE RATES IN THE HIGH BACKGROUND RADIATION AREA OF MANGALORE REGION, INDIA.

Elevated levels of natural background radiation due to scattered patches of monazite sand around the beaches of Mangalore, India, have been reported earlier. A comparative study of gamma dose rates was performed in both normal background and high natural background radiation areas around Mangalore using different types of portable gamma dosimeters. In addition to this, gamma-ray energy spectra were acquired, in situ, using a NaI(Tl) based portable gamma spectrometer. Soil and sand samples were collected for laboratory analysis with HPGe detectors. Measurements were carried out during the years 2016-18 revealed that in majority of the locations the gamma dose rates were similar to the normal background regions, whereas, in certain locations the dose rates were higher with values up to 530 nSv/h.

The expression of MLH1 and MSH2 genes among inhabitants of high background radiation area of Ramsar, Iran

Previous studies evidenced the critical role of the mismatch repair system in DNA damage recognition, cell cycle arrest, apoptosis and DNA repair. MLH1 and MSH2 genes belong to repairing complexes of mismatch repair system. The side effects of ionizing radiation on the human health were proved, but researches on the inhabitants of high background radiation areas, with extra-ordinary radiation exposure, showed that the prevalence of cancer or radiation-related diseases is not significantly higher than normal background areas. The city of Ramsar, in northern Iran, has the highest level of natural background radiation in the world and in this study, we aimed to evaluate the expression of MLH1 and MSH2 genes among the inhabitants of high background radiation areas of Ramsar compared to normal background radiation areas.In the present study, 60 blood sample from high and normal background inhabitants were collected and we MLH1, and MSH2 genes expressions in residents of high background radiation area compared with normal background radiation area were evaluated by Quantitative Real-Time PCR.Our results showed a significant upregulation of MLH1 in residents of high background radiation area. Also, there is a significant association between MLH1 and MSH2 gene expression in both sexes. Also, the increased expression of MLH1 in HBRA is notable. There is an increased expression of MLH1 in age above 50 and a decreased expression of MSH2 in ages under 50 years (P < 0.0001).These findings are suggesting the triggering of Mismatch Repair system in response to high-level of natural background radiation.

Measure the rate of Radiation Activity in Soil sample from the depth of Sindbad land in Basrah Governorate

Uranium, radionuclide’s, thorium and potassium are relatively abundant in soils. Because of their radiation, these radionuclide’s pose exposure risks that can lead to health problems such as cancer for exposed people. There is therefore growing concern about the health risks associated with exposure to the natural sources of radiation in our environment. The specific activity 238U, 232Th, 40K,226Ra in forty soil samples collected from different locations of Al-sindbad land in the province of Basra – Iraq using Sodium Iodide NaI(TL) detector. The specific activities for the whole study areas were compared the Local, world average and permissible recommended limits. The results showed thatthe specific activity of226Ra,232Th,238U, and 40K, in the samples rang from( 17.14-39.07)Bq/kg, ( 1.8-22.88) Bq/kg, (0.68-2.24) Bq/kg and (278.11-402.29)respectively, Also evaluation of radiological hazard effects for Gamma ray (the radium equivalent rate (Raeq) which calculated from concentration of 232Th,238Uand 40K ranges between (30.72-65.48) Bq/kg with mean value of (43.362)Bq/kg, the absorbed dose Rate (D γ ) for the soil samples in the study area range from (26.54-43.92) nGy/h with an average value of(33.216)nGy/h, the annual effective dose rate (AEDEoo) range (0.13-0.22)mSv/y with an average value of(0.163) mSv/y, The annual effective dose rate (AEDEin) range (0.03-0.05) mSv/y with an average value of(0.04) mSv/y, The internal hazard index (Hin) range (0.2-0.35) with an average value of(0.255)and the external hazard index (Hex) range (0.15-0.25) with an average value of (0.186).The results of the present study have shown that the rates of Specific activity of226Ra,238U, 232Th and 40K, and radiological hazard effects Rate for Gamma-ray in environmental samples were all lower than the value of the global limit(33, 35, 30, 400)Bq/kg respectively according to UNSCEAR. We conclude from this study that the environment of Al-Sindbad land in the province of Basra – Iraq is within a normal background radiation.

A Glance at the Errors of Some Studies on the Health Effects of High Background Natural Radiation Areas

There is no place on the Earth, the planet we live on, where the natural background radiation level is zero. Since the birth and even in our fetal stage, we have been exposed to different sources of natural radiation. Life, in fact, evolved in a radiation environment that was much more harsh than today. Earth serves as a source of terrestrial radiation. Uranium, thorium, and radium are among the radioactive materials that naturally exist in soil and rock. Moreover, the air, we breathe, contains radon, a colorless, odorless, radioactive gas that is created naturally by the radioactive decay of uranium and radium. The crucial importance of the studies on the health effects of living in areas with high levels of background radiation for understanding the biological impact of exposure to low doses of ionizing radiation is well documented. Despite the undeniable need for accurate information about the health effects of exposure to high levels of background radiation, many published papers suffer from methodological and other common types of errors. In this paper, we review three articles published on high background radiation areas. The first paper has addressed the frequencies of unstable (dicentrics& rings), stable (translocations & inversions), and other types of chromosome aberration in adult men from both high background radiation areas of Kerala and areas with normal background radiation. The second paper has addressed different aspects of the world’s high background natural radiation areas. Finally, the third paper has tried to address the role of background radiation on males to females’ ratio at birth. The author has mainly referred to the studies performed on the impact of radiation exposures from nuclear testing (worldwide) and Chernobyl fallout (in Europe).The major shortcomings of these three papers, especially methodological errors, which affected the accuracy of their findings and conclusions are discussed.

Association of telomere length with chronic exposure to ionizing radiation among inhabitants of natural high background radiation areas of Ramsar, Iran

Purpose: There are few areas in the world where ionizing radiation (IR) dose received by the public from radon gas and other radioactive elements are much higher than recommended limits. Telomere length is a potential biomarker of genomic instability due to oxidative stress from IR exposure. In this study, we investigated the impact of chronic exposure to environmental IR on relative telomere length (RTL) in white blood cells (WBC) among inhabitants of high background radiation areas (HBRA) of Ramsar, Iran.Materials and methods: One hundred and four individuals from HBRAs of Ramsar and 104 age-matched subjects from normal background radiation areas (NBRA) of Iran were enrolled in the study. The RTLs of WBC DNA samples were measured by a quantitative polymerase chain reaction (q-PCR) approach.Results: Mean RTL in HBRA and NBRA groups did not show any significant difference (1.21 ± 0.71 versus 1.22 ± 0.66, p = .306). After controlling for all demographic variables, less than 1% of the variances in RTL values were related to background radiation exposure.Conclusion: We conclude that chronic exposure to natural IR has no statistically significant effect on RTL among the inhabitants of HBRAs of Ramsar compared with a control group.

Activity concentrations of radionuclides in soil samples along the coastal areas of Kerala, India and the assessment of radiation hazard indices

The present study was carried out along the coastal regions of Kerala, India, to evaluate the distribution of uranium, thorium and potassium concentrations in surface soil samples. A total of 92 soil samples were collected from 9 coastal districts, lying by the side of the Arabian Sea. The radium equivalent activities in the beach sands of Kollam district varies from 877 to 3715 Bq kg−1, which is higher than the reference limit of 370 Bq kg−1. Results show that the radiological parameters obtained for the beach sand from the districts of Thiruvananthapuram, Alapuzha, Eranakulam, Thrissur, Malappuram, Kozhikode, Kannur and Kasaragod are within the safe limits and hence these places can be considered as Normal Background Radiation Areas. Thus, when the high radioactive places are confined to a narrow belt in Kollam district, the other coastal areas of Kerala, especially northern and middle zones are within the safe limit with respect to radiological index.

Using radiation safely in cardiology: what imagers need to know

### Learning objectives Exposure to ionising radiation is an important healthcare concern, primarily due to the potential increased lifetime risk of malignancy. This is important for patients and staff who...

Calibration of Safecast dose rate measurements

A methodology is presented to calibrate contributed Safecast dose rate measurements acquired between 2011 and 2016 in the Fukushima prefecture of Japan. The Safecast data are calibrated using observations acquired by the U.S. Department of Energy at the time of the 2011 Fukushima Daiichi power plant nuclear accident.The methodology performs a series of interpolations between the U.S. government and contributed datasets at specific temporal windows and at corresponding spatial locations. The coefficients found for all the different temporal windows are aggregated and interpolated using quadratic regressions to generate a time dependent calibration function. Normal background radiation, decay rates, and missing values are taken into account during the analysis.Results show that the standard Safecast static transformation function overestimates the official measurements because it fails to capture the presence of two different Cesium isotopes and their changing magnitudes with time. A model is created to predict the ratio of the isotopes from the time of the accident through 2020. The proposed time dependent calibration takes into account this Cesium isotopes ratio, and it is shown to reduce the error between U.S. government and contributed data. The proposed calibration is needed through 2020, after which date the errors introduced by ignoring the presence of different isotopes will become negligible.

Lymphocyte Proliferation Kinetics in Inhabitant of Takandeang Village, Mamuju: A High Background Radiation Areas in Indonesia

BACKGROUND: Mamuju area in West Sulawesi considered as the high natural background radiation area in Indonesia. Our previous study showed that the mean mitotic index (MI) and nuclear division index (NDI) in lymphocytes of Botteng Village, Mamuju inhabitants was lower compared to control samples. To validate our previous study results, here in this study the evaluation of cell proliferation markers which were MI and NDI in peripheral blood lymphocytes (PBL) of Takandeang Village inhabitants was conducted.METHODS: A total 60 people were enrolled in this study, consisted of 35 samples from Takandeang Sub-Village and 25 from normal background radiation area. MI was calculated manually and automatically using Metafer 3.11.2 imaging system. The NDI defined as proportion of mononucleated, binucleated, trinucleated and tetranucleated cells were conducted using cytokinesis block micronucleus (CBMN) assay.RESULTS: The results of this study showed that the mean manual MI in Takandeang Sub-Village inhabitants was lower compared to control group (4.96±2.25 vs. 5.93±2.14). In contrast, the mean automatic MI (20.37±10.49 vs. 18.87±7.49) and NDI (1.555±0.174 vs. 1.523±0.112) in Takandeang Sub-Village inhabitants was higher compared to the control group. Statistical analysis revealed that the difference of mean manual MI, automatic MI and NDI in Takandeang Sub-Village inhabitants was not significantly different compared to the control group(p&gt;0.05).CONCLUSION: It can be concluded that based on this study the chronic low radiation dose exposure in Takandeang Sub-Village, Mamuju has no significant effect on the lymphocytes proliferation.KEYWORDS: lymphocytes, mitotic index, nuclear division index, high background radiation

RADIOLOGICAL HAZARD INDICES OF GRANITIC ROCKS USED FOR THE CONSTRUCTION OF BUILDINGS FROM NUBA MOUNTAINS SUDAN.

This study was conducted to assess the level of radioactivity and the radiation hazards associated with granite rocks used for construction of buildings. The measurement of radioactivity content of the rock samples was performed with gamma-spectrometry equipped with Nal (TI) detector. From the results obtained in this study the average activity concentrations of 226Ra, 232Th and 40K were 20.64, 30.50 and 295.19 Bq kg-1, respectively. The absorbed dose rate in air at 1 m above ground level, the annual effective dose and the gamma index were determined with the aim to assess the possible radiological impact on inhabitants of dwellings built using such rocks. The mean value of the absorbed dose rate, the annual effective dose and the gamma index (Iγ) was 36.36 nGy h-1, 40.79 μSv y-1 and 0.51 μSv y-1, respectively. Radium equivalent activities, and external and internal hazard indices, were also calculated. These data indicated that the area of study lies within areas recognized as normal background radiation and the granite rocks are safe to be used as building material and other structural purposes.