Annual Effective Ingestion Dose Research Articles

Effective dose (ingestion and inhalation) due to radon from tap water samples in children at primary schools in Najaf city, Iraq

Abstract This study focuses on the evolution of radon concentrations in tap water samples of primary schools in Najaf city using a RAD-7 detector. Annual effective doses in children were calculated. A Geographic Information System technique was used for the mapping of radon concentrations, annual effective dose (AED) for ingestion, and inhalation. It was found that the average value of AED due to radon ingestion was 0.236 ± 0.020 μSv/year, while that due to radon ingestion was 0.015 ± 0.0001 nSv/year. Moreover, the range in value of the total AED in μSv/year was 0.015–1.171, with an average value of 0.236 ± 0.020. Radon concentrations in most samples of water comply with the world-wide limits that are approved by WHO and ICRP which state that safe limits (0.5 and 0.4 Bq/L), respectively. Furthermore, all results of the total AED due to radon ingestion and inhalation assessment from radon concentrations in tap water samples collected from the primary schools in Najaf city when used as drinking water were within the global limitations of the WHO. One may conclude that from the results of the AED in children (7–12 years), there is no danger of radon concentrations in the case of human consumption.

Transfer factor of radionuclides from soil to cereal crops around gold mining and evaluation of corresponding radiological hazard levels Oromia, Ethiopia

ABSTRACT Radionuclide distribution and transfer factors in plants are decisive parameters used to evaluate radioactive contamination in the environment and its radiological health risks to humans. In this study, the activities concentration of 226Ra, 232Th, and 40K were measured using NaI(Tl) gamma-ray spectrometry on soils and on corresponding teff and wheat plant samples analyzed collected from Sakaro gold mining area from Reji kebele, Oromia, Ethiopia. The results of mean activity concentration of 226Ra, 232Th, and 40K samples analyzedzed in soil, teff, and wheat samples were found to be 33.05 ± 0.72, 13.7 ± 0.51 and 220.18 ± 0.61 Bq.kg-1, 3.93 ± 0.4,27 ± 0.61 and 148.3 ± 0.5 Bq.kg-1 and 3.22 ± 0.43, 4.59 ± 0.64 and 229.8 ± 0.5 Bq.kg-1 respectively. Results showed that the activity concentration of radionuclides in this study area was within the limit. The transfer factors from soil to cereal crops (teff and wheat) were compared with the study done in a different country of the world and its values were below unity except for 40K in wheat samples. The absorbed dose rate, annual effective dose rate, external and internal hazards index, lifetime cancer risk, and annual effective ingestion dose were estimated and were also compared with the internationally accepted values. It was found that none of the results exceeded the recommended limit value.

Effect of mineral fertilisers application on the transfer of natural radionuclides from soil to radish (Raphanus sativus L.)

Non-controlled usage of mineral fertilisers in agriculture land of Kazakhstan is a concerning issue, due to possible contamination of the soil by radionuclides. Pot experiment of growing of R. sativus with application of mineral fertilisers was carried out under natural conditions. Two commonly used mineral fertilisers, mono-potassium phosphate and ammonium nitrate, were chosen in the frame of current research to determine the impact of mineral fertiliser on transfer of natural radionuclides from soil to R. sativus edible part. For this goal, the activity concentrations of natural radionuclides U-234, U-238, Th-230, Th-232 and Ra-226, were determined in both R. sativus edible part and the investigated soil by using alpha-particle spectrometry. The highest activity concentrations were found for R. sativus edible part growing on soil that was fertilised by mono-potassium phosphate and were equal to 174 ± 17, 134 ± 15, 62 ± 4, 15 ± 2 and 2.8 ± 0.6 Bq/kg for U-234, U-238, Th-230, Th-232 and Ra-226, respectively. The results of soil-to- R. sativus edible part transfer factor for different radionuclides varied depending on the mineral fertiliser used. For evaluation of impact during consumption of R. sativus edible part by a population of Kazakhstan, annual effective ingestion dose and excess lifetime cancer risk were determined. The highest annual effective ingestion dose was found for R. sativus edible part cultivated in mono-potassium phosphate-fertilised soil and was equal to 4.4 μSv year−1.

222Rn and 226Ra Concentrations in Spring Water and Their Dose Assessment Due to Ingestion Intake.

222Rn and 226Ra concentrations of less than a few to several thousands of Bq L−1 have been observed in several underground bodies of water around the world. Although regulations for these concentrations in water have been implemented internationally, there are currently no regulations in place in Japan. However, concentrations that exceed these internationally recognized regulatory values have also been observed in Japan. In this study, concentrations in spring water in the northern part of Japan were measured and the effective dose from intake of the water was evaluated. 222Rn concentrations were measured using a liquid scintillation counter, and 226Ra concentrations were measured using a high purity germanium detector after chemical preparation. The measured 222Rn concentrations (=12.7 ± 6.1 Bq L−1) and 226Ra concentrations (<0.019–0.022 Bq L−1) did not exceed the reference values set by international and European/American organizations. A conservative estimate of the annual effective ingestion dose of 8 μSv for 222Rn and 226Ra obtained in this study is much smaller than the estimated overall annual effective dose of 2.2 mSv from natural radiation to the Japanese population. However, this dosage accounts for 8% of the WHO individual dosing criteria of 0.1 mSv/year for drinking water.

Determination of natural and anthropogenic radioactivity in mushrooms: bioconcentration and dose assessment

This paper presents studies on natural and anthropogenic radioactivity determination in different mushroom species ( Boletus Aereus, Boletus Edulis, Boletus Aestivalis, Agaricus Arvensis, Cantharellus Lutescens, Cantharellus Cibarius, Leccinum Quercinum, Macrolepiota Konradi, Lactarius Deliciosus ) collected in Calabria, southern Italy, aimed at determining 137 Cs and 40 K content in analyzed samples, evaluating the bioconcentration levels and estimating the annual effective dose for ingestion to mushrooms consumers. For all investigated samples, experimental radioactivity results, obtained through High-Purity Germanium (HPGe) gamma spectrometry, were found to be much lower than the specific activity limit set by the international legislation. Information about radionuclides bioaccumulation were given through the calculation of the bioconcentration factor. The effective dose due to the ingestion. of mushrooms by adult members of the population was found to be much lower than the recommended level for the public (1 mSv y -1 ). Results reported in this paper can provide useful information on the environmental risk and can be further used for a radiological mapping of the studied area.

Assessment of physicochemical and radon-attributable radiological parameters of drinking water samples of Pithoragarh district, Uttarakhand

This study evaluates the quality of drinking water samples (sample size = 52) taken from various locations of Pithoragarh district, Uttarakhand. The parameters include physiochemical properties viz. total dissolved solids (TDS in mg/L), electrical conductivity/salinity (µS/cm), pH and radiological dose attributable to radon in water (µSv/y). TDS values for the tested samples varied within the range of 18–434 mg/L with average value of 148 mg/L. Electrical conductivity and pH for these samples was measured as 36–868 µS/cm (average: 296 µS/cm) and 6.8–8.2 (average: 7.2), respectively. Radon activity concentration for these water samples was measured using scintillation-based radon monitor, immediately after sampling at the location site. Radon activity concentration was measured as 0.6–81.9 Bq/L with an average value of 17.8 Bq/L. The paper also estimates the annual effective ingestion dose (µSv/y), annual effective inhalation dose (µSv/y) and total effective dose (µSv/y) attributable to radon in drinking water samples.

Optimization of AlphaGUARD AquaKIT set-up for analysis of radon in water using stainless-steel bottles and its validation through IAEA standard samples

In this study, a system composed of an ionization chamber AlphaGUARD (PQ 2000), an AquaKIT set and an AlphaPUMP was calibrated to measure 222Rn in water. First, the system was checked for leakages using a NIST traceable 226Ra source. Then, we tested polyethylene terephthalate (PET) and stainless-steel bottles for sample storage estimating radon loss over time. Results showed that stainless-steel was a better suitable material for sample storage. Additionally, system setup was further validated by measuring IAEA reference materials issued within the framework of several interlaboratory intercomparisons. Finally, the procedure was applied to bottled mineral and tap waters collected in Sevilla (Spain) including annual effective dose for ingestion for adults children, and infants.

Radiological dose assessments of fish samples due to the presence of NORMs at oil-rich areas of South Africa

This study was conducted to estimate natural radionuclide contents in 24 fish samples collected from rivers of South Africa’s oil-rich and non-oil-rich areas. Also, the radiological analysis was performed to assess the effect of radiation on the population that consumed these fish. A high-resolution Hyper Pure Germanium (HPGe) detector was used to conduct the gamma-ray measurements. The mean activity concentrations for the selected fish samples from the examined areas for 238U, 232Th, and 40K ranged from 8.60 ± 2.97, 4.26 ± 1.18, and 105.66 ± 47.77 for the Bree; 8.06 ± 3.64, 4.84 ± 2.00, and 126.88 ± 47.30 for Klein-Brak; 8.30 ± 3.64, 3.48 ± 1.44, and 90.42 ± 29.35 for Bakens; and 6.48 ± 2.05, 5.26 ± 1.79, and 78.38 ± 20.55 for uMngeni rivers. The annual effective ingestion dose ranged from 0.050 (Argyrosomus japonicus) to 0.100 (Lichia amia) for the Bree; 0.033 (Pomadasys commersonnii) to 0.118 (Pomatomus saltatrix) for Klein-Brak; 0.034 (Enteromius pallidus) to 0.090 (Anguilla marmorata) for Bakens; and 0.046 (A. marmorata) to 0.082 (Hypseleotris cyprinoides) for uMngeni river, respectively. Also, the estimated values for the annual equivalent dose of gonads, bone marrow, and bone surface cells due to ingestion of fish samples ranged from 58.77 to 127.27 for Bree; 42.14 to 125.94 for Klein-Brak; 39.34 to 84.97 for Bakens; and 54.54 to 71.97 for uMngeni rivers (control), respectively. The activity concentrations and radiological dose estimates reported for the studied areas were within the values recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation. Hence, the result of the activity concentrations in the selected fish samples at the time of this study does not pose a radiological risk. The results could also be used as reference data for radioactivity pollution in the study area.

Determination of radon concentration in groundwater of Gadau, Bauchi State, Nigeria and estimation of effective dose

Owing to its proximity to rock and soil, groundwater may contain a non-negligible amount of naturally occurring radioactive materials. If so, the drinking water sourced from deep-bore wells may pose great harm to human health. Acknowledging that water plays a vital role in maintaining a healthy lifestyle, it is important to study the radiological implications of radon gas associated with the intake of groundwater. A total of 10 groundwater samples were analyzed using RAD7 alpha spectrometry (Durridge Co., USA). The measured radon concentration was found to be in the range of 4.92–82.89 (mean 38.3 Bq l−1), which is higher than the US-EPA reference level of 11.1 Bq l−1 or 300 pCi l−1 but within the permissible limit of 100 Bq/m3 set by WHO and EU for indoor radon level (i.e., for inhalation pathway). The values obtained from the studied media were found to be relatively higher than most of the data available in the literature. The mean annual effective dose for ingestion (8.05 μSv y−1) and inhalation (0.10 μSv y−1) was found to be significantly lower than the action level recommended by WHO (0.1 mSv y−1) and ICRP (3–10 mSv y−1), due to 222Rn, 3H and 40K in drinking water. Note that, such a comparison may not reflect the real scenario since our estimated dose is only contributed to by 222Rn. However, the obtained data could serve as a reference for any future radiological study of the waterbody in this region.

Assessment of Radioactivity and Radiological Hazard of Different Food Items Collected from Local Market in Bangladesh

Sixteen samples in three categories vegetables, cereals (rice, wheat, maize, pulse) and powdered milk were collected from local markets (Dhaka city) in Bangladesh and analyzed by using High Purity Germanium (HPGe) Detector for the assessment of natural and artificial radioactivity. In vegetables (potato, raw banana, giant taro, red amaranth), the average activity concentrations of 232Th, 226Ra, and 40K were found to be 37.82±11.57, 54.93±9.98 and 617.43±65.69 Bqkg-1 respectively, for cereals (rice, wheat, maize, pulse) 24.01±3.67, 31.46±4.00 and 474.83±27.68 Bqkg-1 respectively and for milk samples 15.01±3.65, 26.73±6.77 and 494.21±38.71 Bqkg-1 respectively. The average values of outdoor annual effective dose were found to be 92.18, 61.19 and 52.37μSvy-1 in vegetables, cereals and milk samples respectively. No artificial radionuclide was found in any of these samples. The average value of radium equivalent activity in all samples was 113.89 Bqkg-1 which was less than maximum permissible value 370 Bqkg-1. The values of external hazard indices for vegetables, cereals and milk samples varied from 0.31 to 0.66, 0.17 to 0.40 and 0.11 to 0.36 respectively which is less than unity in all samples that indicate the non-hazardous nature of the samples. The average values of annual effective ingestion dose rate from foods (for adult) were 274.33 μSvy-1, 533.60μSvy-1, and 132.73μSvy-1for 232Th, 226Ra and 40K respectively. These data would be useful to establish a baseline for natural radioactivity concentrations in food items consumed in Bangladesh.&#x0D; Journal of Bangladesh Academy of Sciences, Vol. 43, No. 2, 141-148, 2019

Radon activity concentration measurements in water sources from Perak state Malaysia

Radon activity concentration in water samples from Perak state Malaysia and their possible health risk was assessed. The Samples were from lakes, hot springs, and rivers. The RAD7 Detector was used for in-situ measurement of radon concentration. The radon activity concentration ranged from 0.04 ± 0.08 — 3.98 ± 0.39 Bq l – 1, with mean of 0.69 Bq l – 1 and standard deviation of 0.92 Bq l – 1. The activity concentration ranged from 0.08 ± 0.12 — 0.45 ± 0.27, 0.04 ± 0.08 — 0.62 ± 0.32, 0.33 ± 0.23 — 3.98 ± 0.39 Bq l – 1, with a mean of 0.24 ± 0.19, 0.30 ± 0.21, 1.26 ± 0.34 Bq l – 1 for lakes, hot springs, and rivers respectively. The result was below the UNSCEAR, USEPA and WHO action levels of 11.1 Bq l– 1and100 Bq l – 1respectively. The 222Rn contribution from water to indoor air was found to be below the recommended action level . The annual effective dose for inhalation and ingestion ranged from 0.000102 — 0.009954 mSv y – 1 and 0.000102 — 0.010112 mSv y – 1, with mean annual effective dose of 0.001733 and 0.001759 mSv y – 1 respectively. The effective doses for both inhalation and ingestion were below the world average of 0.002 mSv y – 1. The 222Rn activity concentration in the study could be termed normal and without threat to human health.

Investigation of the Natural Occurring Radioactive Material (NORM) in the cyprinus carpio fishes breeding in artificial lakes of Baghdad governorate

The steady consumption of fish led many researchers to study it preferences over other foods, especially for radioactivity content. The specific activity concentration (S.A) of natural occurring radioactive materials (NORM) have been measured for Cyprinus carpio fishes collected from several industrial fishes' lakes located in Baghdad governorate using gamma spectroscopy doped with high purity germanium coaxial detector (HPGe). Thirteen fishes' samples were collected from industrial lakes, three samples were collected from cages, and two samples were collected from Trigger River. The last two types of samples were collected in order to compare the results with it. The measured overall averages of S.A for Ra-226, Th-232, and K-40 were 58.9 Bq/kg, 14.1 Bq/kg, and 388.6 Bq/kg, respectively. Some radiation health hazard indices have been estimated, such as the annual effective ingestion dose for an adult member of the public due to the intake of radionuclide through ingestion of fish (H). The results of H showed that the cage fish is better than river fishes and lakes fishes. However, the results of S.A and H strongly suggested that the studied fish is safe to use for human consumption from radiological point of view.

Uptake of natural radionuclides from contaminated soil into vegetables and consequent dose assessment

Selected natural radionuclides from the uranium decay chain were determined in radish, savoy and rocket grown in uranium mill tailing contaminated growth substrates. The data obtained were used in calculation of dose assessment. Based on the results obtained for activity concentrations of four radionuclides (238U, 230Th, 226Ra and 210Pb) in vegetables, cultivated in contaminated soil, the committed effective doses, along with the maximum values for adults, were estimated. Statistical analyses of linear correlation among calculated annual effective ingestion dose and uranium mill tailings showed to be highly significant.

Transfer factor of 226Ra, 232Th and 40K from soil to Alpinia Galangal plant grown in northern Thailand

This paper reports the activity concentration of three natural radionuclides, 226Ra, 232Th and 40K, found in Alpinia Galangal plants which are widely used in various Asian cuisines and traditional medicine. The galangal plants and their relevant soils were collected from four provinces in the north of Thailand under natural field conditions. The activity concentration of radionuclides was determined using gamma-ray spectrometry. Soil-to-plant transfer factors (TFs) for 226Ra, 232Th and 40K were investigated in rhizome and aerial parts of the galangal plants. The activity concentration in the soils ranged from 22 to 88 Bq kg-1 for 226Ra, 27 to 157 Bq kg-1 for 232Th and 58 to 1157 Bq kg-1 for 40K. In Alpinia Galangal, the concentration ranged from < 0.2 to 2.0 Bq kg-1 for 226Ra, < 0.1 to 2.9 Bq kg-1 for 232Th and 205 to 2247 Bq kg-1 for 40K. The TF ranged from < 0.002 to 0.073 for 226Ra, < 0.001 to 0.061 for 232Th and 0.26 to 7.9 for 40K. The TFs in the aerial parts were higher than those for the rhizomes. The obtained values can be considered as a baseline data for activity concentrations of natural radionuclides and their TFs in Thailand for future environmental radiation monitoring. The Annual effective ingestion dose due to ingestion of 226Ra, 232Th and 40K in galangals is significantly below the worldwide value reported by UNSCEAR 2000.

Assessment of Radiation Dose from Exposure to Radon in Drinking Water from Western Haryana, India

The radon concentration has been determined in 95 groundwater samples collected from 28 villages/towns in the Hisar district of Haryana, India. The measurements were performed by RAD7, an electronic solid-state alpha detector manufactured by Durridge Company Inc. The measured mean radon concentration in water samples ranged between 1.4 ± 0.3 and 13.3 ± 4.1 Bq l−1. The mean radon concentrations from three locations exceeded the maximum contamination level (MCL) of 11 Bq l−1 recommended by United States Environmental Protection Agency. The annual effective dose for ingestion and inhalation was also evaluated in this research. The total annual effective dose due to ingestion and inhalation of radon in drinking water ranged from 13.7 to 130.3 µSv year−1.

Radon levels in drinking water of Fatehabad district of Haryana, India

Radon concentrations were measured in 59 groundwater samples collected from Fatehabad district of Haryana, India. The measurements were performed by RAD7 an electronic radon detector manufactured by Durridge Company Inc. The measured radon concentration ranged from 1.4 to 22.6Bql−1. 14% of the groundwater samples were above the United States Environmental Protection Agency recommended value for radon in water. The annual effective dose for ingestion and inhalation was also evaluated in this research. The total annual effective dose due to ingestion and inhalation of radon in drinking water varied from 14.1 to 221.8µSvy−1.

A study of radon concentration in drinking water samples of Amritsar city of Punjab (India)

Radon concentration has been estimated in drinking water samples of 17 selected locations in Amritsar city of Punjab, India. RAD7, an electronic solid state radon monitor has been used to evaluate the radon concentration in collected drinking water samples. The corresponding annual mean effective dose for ingestion and inhalation was calculated according to parameters introduced by UNSCEAR (2000) report. The radon concentration in drinking water samples has been found to vary from 0.53 ± 0.11 to 11.20 ± 1.40 Bql−1 . The values of radon concentration in these samples were found below the recommended limit proposed by USEPA (1991) and European Commission (2001). The range of calculated annual effective dose varied between 1.45 and 30.57 ΅Svy−1 . These values lie well within the safe limit prescribed by the WHO (2003) and European council (2005). The purpose of this study was to assess the radiological risk, if any, to human health due to consumption of drinking water that is available at Amritsar city.

Dose assessments from the measured radioactivity in soil, rock, clay, sediment and food crop samples of an elevated radiation area in south-western Nigeria

Activity concentrations of 40K, 226Ra and 232Th were measured in five different environmental matrices and food crops collected from some elevated radiation areas of Sikiti south-west Nigeria to estimate the radiation dose incur by the population. In situ gamma dose rates were also measured at every collection point for comparison. The activity concentrations of the various radionuclides obtained for rock samples collected from mining sites were generally higher than those of other matrices except 226Ra that is relatively low in rocks of the study area. Radiological hazard indices were estimated to assess the harmful effects of gamma radiation to the population dwelling in the area. The activity concentrations and the estimated radiological parameters were comparable to values obtained in elevated radiation areas around the world. The mean in situ measured absorbed dose rate is 232.8 ± 49.8 nGy h−1, which is far greater than the worldwide mean outdoor value of 60 nGy h−1. The total annual effective ingestion dose obtained in this study is 339.4 µSv year−1, which is higher than the 290 µSv year−1 reported as the world average value. Also, the total annual effective dose due to external and internal gamma radiation exposures in the study area is 1.83 mSv year−1, which is greater than the 1 mSv year−1 recommended by ICRP for members of the public. It can therefore be concluded that the radiological risks to the general population from gamma radiation due to natural radionuclides in the area are significant.

Determination of activity concentration of 210Po in mussels (Mytilus galloprovincialis) from Butrinti Lagoon, Albanian Ionian coast

This study reports the activity concentration of 210Po in mussels (Mytilus galloprovincialis) from Butrinti Lagoon. The concentrations of 210Po in mussels collected in spring are found to be approximately twice higher than those collected in autumn, respectively 389.5 ± 16.9 and 227.4 ± 5.0 Bq kg−1 (d.w.). Hypothesis on factors affecting 210Po concentration in mussels are raised based on available studies. The annual effective ingestion dose due to 210Po intake was found to be comparable to other studies and varying from 74.2 ± 3.4 to 36.5 ± 1.0 µSv y−1.

Improvement of measuring methods and instrumentation concerning 222Rn determination in drinking waters – RAD7 and LSC technique comparison

A procedure for the determination of 222Rn in environmental water samples using liquid scintillation counting (LSC) was applied and optimized. A minimum detectable activity of 0.029Bql−1 in a 20ml glass vial (10ml water sample mixed with 10ml of liquid scintillation cocktail) has been achieved during 300min of measurement time. The procedure was compared with RAD7 radon detector measurements. 226Ra content in the water was determined by gamma-ray spectroscopy. Applications to drinking waters collected from public drinking fountains in the Vojvodina (Serbia) are presented with annual effective dose for ingestion and inhalation for adults calculated.