Some of non-renewable water resources such as deep groundwater aquifers were explored extensively... more Some of non-renewable water resources such as deep groundwater aquifers were explored extensively for the use as drinking water. Water treatment plants (WTPs) were established to fulfill the standards of drinking water quality. The study of the chemical behavior of uranium (U) in groundwater treatment process is the main aim of this work that will shed more light on U removal efficiency during water treatment processes. Samples represent various treatment processes such as sand filtration and reverse osmosis were collected. Uranium and other elements (e.g. Ba, Ca, Fe, K, Mg, Na and Sr) concentrations were measured using ICP-MS that shows a wide range of variation. In addition, some physicochemical parameters such as pH, electric conductivity-EC, major cations (Ca 2+ , Mg 2+ , Na + and K +) and major anions (CO 3 2-, HCO3-, Cland SO4 2-) were measured. The removal efficiency of U was about 99% by reverse osmosis (RO) process that leads to increasing the U concentration (293%) in RO reject and consequently in evaporation bond. The concentration of U and other toxic elements in evaporation bond's water could be a serious potential source of environmental contamination due to their continuous increase with water volume reduction.
Phosphate and environmental samples were collected from Abu Tartor phosphate mine and the surroun... more Phosphate and environmental samples were collected from Abu Tartor phosphate mine and the surrounding region. The activity concentration of 226 Ra ( 238 U) series, 232 Th series and 40 K were measured using a gamma-ray ...
Due to the relatively high activity concentrations of 210 Po and 210 Pb that are found in tobacco... more Due to the relatively high activity concentrations of 210 Po and 210 Pb that are found in tobacco and its products, cigarette smoking highly increases the internal intake of both radionuclides and their concentrations in the lung ...
This paper represents the first work on the concentrations of heavy elements, physiochemical char... more This paper represents the first work on the concentrations of heavy elements, physiochemical characteristics and activity levels of the naturally occurring radionuclides in the Saudi Arabian coastline of the Gulf of Aqaba. Concentrations of 19 heavy elements were measured, namely: Ag,
Page 1. Uranium accumulation in sandy soil in an arid region due to agricultural activities Ashra... more Page 1. Uranium accumulation in sandy soil in an arid region due to agricultural activities Ashraf EM Khater1&2, AS Al-Saif2 and HA AL-Sewaidan2 1National Center for Nuclear Safety and Radiation Control, Atomic Energy ...
Manufactured phosphate fertilizers and their agricultural applications are considerable sources o... more Manufactured phosphate fertilizers and their agricultural applications are considerable sources of environmental pollution. In this study, composite samples of phosphate fertilizer (PF) of different physical forms (granular, G, and water soluble powder, L) were collected. The activity concentration of 238U in Bq kg(-1) was measured using gamma ray spectrometers, and the concentrations of arsenic, cadmium, copper, lead and selenium in mg kg(-1) were measured using inductively coupled plasma optical emission spectrometers (ICP-OES). The main aims of this study were to evaluate PF quality according to its physical form, determine manufacturers (local, L, or imported, I), and estimate the hazardous impacts of long-term phosphate fertilization. There was significant variation in the concentration of uranium and other elements in PF samples. In order to have globally normalized data, it is highly recommended to express the concentration of trace elements as per phosphorus mass instead of fertilizer mass. The annual addition of these elements to soil due to phosphate fertilization was calculated. The possible accumulation of added uranium and other trace elements due to fertilization in the subsurface soil layer and/or shallow underground water should be studied in the soil environment of Saudi Arabia.
Objective: Nerve blockade is commonly used in oncosurgical procedures as an alternative to genera... more Objective: Nerve blockade is commonly used in oncosurgical procedures as an alternative to general anesthesia for older patients and those with significant medical problems. We report a single tertiary oncology center experience in performing various lip resections and reconstructive techniques using this technique. Patients and methods: sixty patients with lower lip tumors were enrolled into this study with exclusion of refusing, non-compliant and critically ill patients. A solution of 4 ml 2% Lidocaine and epinephrine was put in a 5 ml syringe. Half the solution (2 ml) was injected into each side with a 23 gauge needle and after 5 minutes the surgical resection was carried out after testing for anesthesia. Results: The mean age was 68 ± 6.2 years. The mean ASA score was 3 ± 0.75. There were 4 cases who expressed painful sensation and their operations were completed with fentanyl increments. Mean hospital stay was 1 ± 0.75 days. There were three cases of wound gaping who were treated with secondary closure in an outpatient basis. One patient expressed postoperative acute ischemic heart pain that was managed with anti-ischemic measurements. Conclusion: Bilateral mental nerve block is a safe and effective alternative to general anesthesia in lower lip tumors' resection especially in older patients and those with poor tolerance for general anesthesia provided that there is no need for cervical nodal dissection.
The Red Sea is a deep semi-enclosed and narrow basin connected to the Indian Ocean by a narrow si... more The Red Sea is a deep semi-enclosed and narrow basin connected to the Indian Ocean by a narrow sill in the south and to the Suez Canal in the north. Oil industries in the Gulf of Suez, phosphate ore mining activities in Safaga— ...
This paper represents the first work on the concentrations of heavy elements, physiochemical char... more This paper represents the first work on the concentrations of heavy elements, physiochemical characteristics and activity levels of the naturally occurring radionuclides in the Saudi Arabian coastline of the Gulf of Aqaba. Concentrations of 19 heavy elements were measured, namely: Ag, Al, As, Ba, Be, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Se, V and Zn. The radioactivity levels of 238 U, 232 Th and 40 K were estimated to be: 17 ± 1.7, 22.5 ± 3.7 and 649.6 ± 64.2 Bq kg À1 , respectively. The measurements were carried out using inductively coupled plasmamass spectrometry (ICP-MS). In addition, physiochemical characteristics of 19 sediment samples (i.e., saturation percentage, pH, electrical conductivity, organic matter, cation exchange capacity and content of clay, silt and sand) have been determined. Indications for high correlation between most heavy elements are found. The correlation between heavy elements and the radionuclides 238 U, 232 Th and 40 K was generally significant.
The near shore of the Red Sea marine ecosystem could be impacted by some urban and industrial act... more The near shore of the Red Sea marine ecosystem could be impacted by some urban and industrial activities such as phosphate mining, oil industry, seawater desalination, recreation, housing, sewage, waste disposal and shipping. This study aims to investigate the relationship between concentration, distribution pattern and the enrichment of both barium (Ba) and phosphate (P), and some industrial activities such as oil exploration and production, and phosphate mining and
This work was carried out to analyze and compare Hazm El-Jalamid phosphate ores-Saudi Arabia with... more This work was carried out to analyze and compare Hazm El-Jalamid phosphate ores-Saudi Arabia with other ores, for their uranium (U) and rare earth elements (REE) abundance and geochemical pattern. Fifteen representative phosphate ore samples were collected from three phosphate mines (Hazm El-Jalamid and Umm Wu'al) in Saudi Arabia and (El-Sibayia) Egypt and analyzed for some elements (Si, Al, Fe, Ca, Mg, Na, K, Cr, Ti, Mn, P, Sr and Ba), U and REEs using inductively coupled plasma mass spectrometry. Detailed studies of the Hazm El-Jalamid phosphorite samples were conducted using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The average U contents in the Hazm El-Jalamid samples were considerably lower than those of other phosphate ores from different origens and countries. The SEM-EDX analyses reveal the presence of uraniumbearing minerals (apatite) and uranyl vanadate minerals [carnotite, K 2 (UO 2 ) 2 (VO 4 )]. The highest REE concentration values were recorded for La in all samples, followed by Ce and Nd. The lowest REE concentrations were recorded for Tm in all samples. Hazm El-Jalamid phosphate samples are highly enriched in heavy REEs (HREEs) and depleted in light REEs (LREEs), except for La. The REEs exhibit the same behavior in the phosphate deposits of Hazm El-Jalamid, Umm Wu'al, El-Sibayia, Florida and Morocco and the opposite behavior in the phosphate deposits from Jordon and Kola, which are enriched in LREEs (except for La) and depleted in HREEs.
Cigarette smoking is documented source of human internal intake of toxic trace and heavy metals. ... more Cigarette smoking is documented source of human internal intake of toxic trace and heavy metals. However, data about tobacco-derived products such as moassel/tabamel and jurak, used in the growingly popular shisha (narghile, hookah), have been scarce and scattered. In these conditions, the objective of this study, the first ever carried out on this scale, was to investigate the elemental contents of moassel and jurak and compare it with that of other tobacco products. Representative samples from 3 different moassel brands were collected. Concentration of 34 elements was measured using the Inductively Coupled Plasma Mass Spectrometer (ICP-MS). Results show that trace elements are much more abundant in cigarette tobacco than in shisha moassel. A wide range of variations was observed. For instance, the levels of As, Cd and Ni (mg kg -1 ) were: 1.59, 1.0 and 0.146; 1.45, 0.5 and 0.075; 3.5, 5 and 0.63; for, respectively: cigarette, moassel and jurak. Since shisha smoking is continuously targeted by antismoking groups as a "global epidemic", a public health priority should be the design of culturally tailored products (for instance resins prepared from local plants to be mixed with the water of the pipes) based on well-established harm reduction techniques.
In this study, uranium concentrations (ppm) and the natural activity ratios ( 235 U/ 238 U) in 6 ... more In this study, uranium concentrations (ppm) and the natural activity ratios ( 235 U/ 238 U) in 6 representative samples of uranium ore samples were analyzed. The samples were collected from Gattar II ore site, which is located at the Red Sea northeastern desert of Egypt. The samples were measured using HPGe gamma ray detector (non-destructive technique) based on the measurement of the emitted gamma rays of uranium by using the photo peaks 163.33 keV for 235 U to avoid the overlapping with 186 keV of 226 Ra, and the 1001.03 keV photo peak of 234m Pa daughter for 238 U concentration respectively. The uranium concentrations of the same analyzed samples were determined using ICP-MS (destructive technique) for comparison. Sharp correlation (R 2 =0.9881) was found between uranium concentration measured by non-destructive gamma ray spectrometry and that measured by destructive ICP-MS for the same analyzed samples.
The coast of the Gulf of Aqaba is subjected to several sources of pollution due to several activi... more The coast of the Gulf of Aqaba is subjected to several sources of pollution due to several activities occurring at the coastal area. The activities vary between industrial, tourist and other development aspects at the Jordanian coastline of the Gulf of Aqaba. Phosphate industry has been considered a major source polluting the marine environment. According to official reports, 4-7 million tons of raw phosphate is exported through the Gulf of Aqaba. During transportation and loading, a small proportion of this enters the waters of the Gulf. Phosphate dust has also been considered another source of nutrients loading to the Gulf. 19 sediment samples were collected along the Saudi Gulf coastline, from the Saudi-Jordan border down to the end of the Gulf at Tiran Strait. Measurements of the activity concentrations of 226 Ra, 232 Th, 40 K and 137 Cs in Bq/kg (in dry weight) of the collected samples were carried out using gamma-ray spectrometry based on a highly pure germanium coaxial detector (HPGe). The concentrations of 238 U and 232 Th were also determined using ICP-MS technique. The average specific activities for 226 Ra, 232 Th, 40 K and 137 Cs were found to be 11.4 7 1.5, 22.5 7 3.7, 641.1 761.3 and 3.5 7 0.7 Bq/kg, respectively. The results show that the mean activity of 226 Ra and 232 Th is lower than the world average of 25 Bq/kg for both of them, whereas the mean value for 40 K is about double the world average of 370 Bq/kg. The presence of 137 Cs in the analyzed samples is low in most locations. The mean concentrations of 238 U and 232 Th in the study area are 1.2 and 5.4 mg/kg, respectively, and the ratio 238 U/ 232 Th is 0.2, which is lower than the global ratio of 0.3. The ratio of 226 Ra/ 228 Ra was found to decrease southwards in the direction of Tiran Strait, away from the phosphate industry in Jordan. Mean values for radium equivalent, absorbed dose, annual effective dose, external and internal hazard index and representative level index were determined as: 92.9 Bq/kg, 45.6 nGy/h, 56.0 mSv/y, 0.13, 0.28 and 0.73, respectively.
Clays are among the most important industrially used minerals. Three potential clay mineral minin... more Clays are among the most important industrially used minerals. Three potential clay mineral mining sites in Saudi Arabia were chosen, and 21 clay deposit samples were collected. The activity concentrations (average+ + + + +standard deviation) of the naturally occurring radioactive materials (NORMs), 238 U, 226 Ra, 232 Th, 228 Ra and 40 K, were 49+ + + + +20, 47+ + + + +23, 34+ + + + +11, 40+ + + + +20 and 751 Bq kg 21 , respectively. The radiation dose assessments (e.g., absorbed dose rate, nGy h 21 ; effective dose equivalent, mSv y 21 ; and effective dose rate due to dust inhalation, mSv y 21 ) and hazardous indices (e.g., radium equivalent [Ra-eq] value, external hazardous index [H ex ], internal hazardous index [H in ] and representative gamma level [I g ]) were calculated. The wide variations in the activity concentrations of the NORMs according to sampling region could be due to the origen of the geological formation and the geochemical behaviour of the NORMs. Based on calculated hazardous (external and internal) indices, there were no expected radiological hazardous impacts of using clay deposits as building materials.
The Red Sea is a deep semi-enclosed and narrow basin connected to the Indian Ocean by a narrow si... more The Red Sea is a deep semi-enclosed and narrow basin connected to the Indian Ocean by a narrow sill in the south and to the Suez Canal in the north. Oil industries in the Gulf of Suez, phosphate ore mining activities in Safaga-Quseir region and intensified navigation activities are non-nuclear pollution sources that could have serious radiological impacts on the marine environment and the coastal ecosystems of the Red Sea. It is essential to establish the radiological base-line data, which does not exist yet, and to investigate the present radio-ecological impact of the non-nuclear industries to preserve and protect the coastal environment of the Red Sea. Some natural and man-made radionuclides have been measured in shore sediment samples collected from the Egyptian coast of the Red Sea. The specific activities of 226 Ra and 210 Pb ( 238 U) series, 232 Th series, 40 K and 137 Cs (Bq/kg dry weight) were measured using gamma ray spectrometers based on hyper-pure germanium detectors. The specific activities of 210 Po ( 210 Pb) and uranium isotopes ( 238 U, 235 U and 234 U) (Bq/kg dry weight) were measured using alpha spectrometers based on surface barrier (PIPS) detectors after radiochemical separation. The absorbed radiation dose rates in air (nGy/h) due to natural radionuclides in shore sediment and radium equivalent activity index (Bq/kg) were calculated. The specific activity ratios of 228 Ra/ 226 Ra, 210 Pb/ 226 Ra, 226 Ra/ 238 U and 234 U/ 238 U were calculated for evaluation of the geo-chemical behaviour of these radionuclides. The average specific activity of 226 Ra ( 238 U) series, 232 Th series, 40 K and 210 Pb were 24.7, 31.4, 427.5 and 25.6 Bq/kg, respectively. The concentration of 137 Cs in the sediment samples was less than the lower limit of detection. The Red Sea coast is an arid à Corresponding author. Present address: region with very low rainfall and the sediment is mainly composed of sand. The specific activity of 238 U, 235 U and 234 U were 25.3, 2.9 and 25.0 Bq/kg. The average specific activity ratios of 226 Ra/ 228 Ra, 210 Pb/ 226 Ra and 234 U/ 238 U were 1.67, 1.22 and 1.0, respectively.
Phosphate and environmental samples were collected from Abu Tartor phosphate mine and the surroun... more Phosphate and environmental samples were collected from Abu Tartor phosphate mine and the surrounding region. The activity concentration of 226 Ra ( 238 U) series, 232 Th series and 40 K were measured using a gamma-ray spectrometer. The activities of uranium isotopes ( 238 U, 235 U and 234 U) and 210 Pb were measured using an alpha spectrometer and a low-background proportional gas counting system, respectively, after radiochemical separation. The results are discussed and compared with the levels in phosphate rocks from different countries. It seems that the Abu Tartor phosphate deposit has the lowest radioactivity level of exploited phosphate of sedimentary origen. 226 Ra/ 238 U, 210 Pb/ 226 Ra, 234 U/ 238 U and 226 Ra/ 228 Ra activity ratios were calculated and are discussed. The radioactivity levels in the surrounding region and the calculated exposure dose (nGy/h) will be considered as a pre-operational baseline to estimate the possible radiological impacts due to mining, processing and future phosphate industrial activities. To minimize these impacts, the processing wastes should be recycled to the greatest possible extent. #
Under the Egyptian program for radiation safety and control, airborne radioactivity measurements ... more Under the Egyptian program for radiation safety and control, airborne radioactivity measurements and radiological dose assessment were conducted in some phosphate and uranium mines. Abu-Tartor mine is one of the biggest underground phosphate mines in Egypt. Airborne radioactivity, radon ( 222 Rn) and its short-lived decay products (progenies) and thoron ( 220 Rn), were measured in selected locations along the mine. The environmental gamma and workers dose equivalent rate (mSv/y) were measured inside and outside the mine using thermo-luminescence dosimeters (TLD). The results were presented and discussed. The calculated annual effective dose due to airborne radioactivity is the main source of occupational exposure and exceeding the maximum recommended level by ICRP-60 inside the mine tunnels. A number of recommendations are suggested to control the occupational exposures. #
Some of non-renewable water resources such as deep groundwater aquifers were explored extensively... more Some of non-renewable water resources such as deep groundwater aquifers were explored extensively for the use as drinking water. Water treatment plants (WTPs) were established to fulfill the standards of drinking water quality. The study of the chemical behavior of uranium (U) in groundwater treatment process is the main aim of this work that will shed more light on U removal efficiency during water treatment processes. Samples represent various treatment processes such as sand filtration and reverse osmosis were collected. Uranium and other elements (e.g. Ba, Ca, Fe, K, Mg, Na and Sr) concentrations were measured using ICP-MS that shows a wide range of variation. In addition, some physicochemical parameters such as pH, electric conductivity-EC, major cations (Ca 2+ , Mg 2+ , Na + and K +) and major anions (CO 3 2-, HCO3-, Cland SO4 2-) were measured. The removal efficiency of U was about 99% by reverse osmosis (RO) process that leads to increasing the U concentration (293%) in RO reject and consequently in evaporation bond. The concentration of U and other toxic elements in evaporation bond's water could be a serious potential source of environmental contamination due to their continuous increase with water volume reduction.
Phosphate and environmental samples were collected from Abu Tartor phosphate mine and the surroun... more Phosphate and environmental samples were collected from Abu Tartor phosphate mine and the surrounding region. The activity concentration of 226 Ra ( 238 U) series, 232 Th series and 40 K were measured using a gamma-ray ...
Due to the relatively high activity concentrations of 210 Po and 210 Pb that are found in tobacco... more Due to the relatively high activity concentrations of 210 Po and 210 Pb that are found in tobacco and its products, cigarette smoking highly increases the internal intake of both radionuclides and their concentrations in the lung ...
This paper represents the first work on the concentrations of heavy elements, physiochemical char... more This paper represents the first work on the concentrations of heavy elements, physiochemical characteristics and activity levels of the naturally occurring radionuclides in the Saudi Arabian coastline of the Gulf of Aqaba. Concentrations of 19 heavy elements were measured, namely: Ag,
Page 1. Uranium accumulation in sandy soil in an arid region due to agricultural activities Ashra... more Page 1. Uranium accumulation in sandy soil in an arid region due to agricultural activities Ashraf EM Khater1&2, AS Al-Saif2 and HA AL-Sewaidan2 1National Center for Nuclear Safety and Radiation Control, Atomic Energy ...
Manufactured phosphate fertilizers and their agricultural applications are considerable sources o... more Manufactured phosphate fertilizers and their agricultural applications are considerable sources of environmental pollution. In this study, composite samples of phosphate fertilizer (PF) of different physical forms (granular, G, and water soluble powder, L) were collected. The activity concentration of 238U in Bq kg(-1) was measured using gamma ray spectrometers, and the concentrations of arsenic, cadmium, copper, lead and selenium in mg kg(-1) were measured using inductively coupled plasma optical emission spectrometers (ICP-OES). The main aims of this study were to evaluate PF quality according to its physical form, determine manufacturers (local, L, or imported, I), and estimate the hazardous impacts of long-term phosphate fertilization. There was significant variation in the concentration of uranium and other elements in PF samples. In order to have globally normalized data, it is highly recommended to express the concentration of trace elements as per phosphorus mass instead of fertilizer mass. The annual addition of these elements to soil due to phosphate fertilization was calculated. The possible accumulation of added uranium and other trace elements due to fertilization in the subsurface soil layer and/or shallow underground water should be studied in the soil environment of Saudi Arabia.
Objective: Nerve blockade is commonly used in oncosurgical procedures as an alternative to genera... more Objective: Nerve blockade is commonly used in oncosurgical procedures as an alternative to general anesthesia for older patients and those with significant medical problems. We report a single tertiary oncology center experience in performing various lip resections and reconstructive techniques using this technique. Patients and methods: sixty patients with lower lip tumors were enrolled into this study with exclusion of refusing, non-compliant and critically ill patients. A solution of 4 ml 2% Lidocaine and epinephrine was put in a 5 ml syringe. Half the solution (2 ml) was injected into each side with a 23 gauge needle and after 5 minutes the surgical resection was carried out after testing for anesthesia. Results: The mean age was 68 ± 6.2 years. The mean ASA score was 3 ± 0.75. There were 4 cases who expressed painful sensation and their operations were completed with fentanyl increments. Mean hospital stay was 1 ± 0.75 days. There were three cases of wound gaping who were treated with secondary closure in an outpatient basis. One patient expressed postoperative acute ischemic heart pain that was managed with anti-ischemic measurements. Conclusion: Bilateral mental nerve block is a safe and effective alternative to general anesthesia in lower lip tumors' resection especially in older patients and those with poor tolerance for general anesthesia provided that there is no need for cervical nodal dissection.
The Red Sea is a deep semi-enclosed and narrow basin connected to the Indian Ocean by a narrow si... more The Red Sea is a deep semi-enclosed and narrow basin connected to the Indian Ocean by a narrow sill in the south and to the Suez Canal in the north. Oil industries in the Gulf of Suez, phosphate ore mining activities in Safaga— ...
This paper represents the first work on the concentrations of heavy elements, physiochemical char... more This paper represents the first work on the concentrations of heavy elements, physiochemical characteristics and activity levels of the naturally occurring radionuclides in the Saudi Arabian coastline of the Gulf of Aqaba. Concentrations of 19 heavy elements were measured, namely: Ag, Al, As, Ba, Be, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Se, V and Zn. The radioactivity levels of 238 U, 232 Th and 40 K were estimated to be: 17 ± 1.7, 22.5 ± 3.7 and 649.6 ± 64.2 Bq kg À1 , respectively. The measurements were carried out using inductively coupled plasmamass spectrometry (ICP-MS). In addition, physiochemical characteristics of 19 sediment samples (i.e., saturation percentage, pH, electrical conductivity, organic matter, cation exchange capacity and content of clay, silt and sand) have been determined. Indications for high correlation between most heavy elements are found. The correlation between heavy elements and the radionuclides 238 U, 232 Th and 40 K was generally significant.
The near shore of the Red Sea marine ecosystem could be impacted by some urban and industrial act... more The near shore of the Red Sea marine ecosystem could be impacted by some urban and industrial activities such as phosphate mining, oil industry, seawater desalination, recreation, housing, sewage, waste disposal and shipping. This study aims to investigate the relationship between concentration, distribution pattern and the enrichment of both barium (Ba) and phosphate (P), and some industrial activities such as oil exploration and production, and phosphate mining and
This work was carried out to analyze and compare Hazm El-Jalamid phosphate ores-Saudi Arabia with... more This work was carried out to analyze and compare Hazm El-Jalamid phosphate ores-Saudi Arabia with other ores, for their uranium (U) and rare earth elements (REE) abundance and geochemical pattern. Fifteen representative phosphate ore samples were collected from three phosphate mines (Hazm El-Jalamid and Umm Wu'al) in Saudi Arabia and (El-Sibayia) Egypt and analyzed for some elements (Si, Al, Fe, Ca, Mg, Na, K, Cr, Ti, Mn, P, Sr and Ba), U and REEs using inductively coupled plasma mass spectrometry. Detailed studies of the Hazm El-Jalamid phosphorite samples were conducted using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The average U contents in the Hazm El-Jalamid samples were considerably lower than those of other phosphate ores from different origens and countries. The SEM-EDX analyses reveal the presence of uraniumbearing minerals (apatite) and uranyl vanadate minerals [carnotite, K 2 (UO 2 ) 2 (VO 4 )]. The highest REE concentration values were recorded for La in all samples, followed by Ce and Nd. The lowest REE concentrations were recorded for Tm in all samples. Hazm El-Jalamid phosphate samples are highly enriched in heavy REEs (HREEs) and depleted in light REEs (LREEs), except for La. The REEs exhibit the same behavior in the phosphate deposits of Hazm El-Jalamid, Umm Wu'al, El-Sibayia, Florida and Morocco and the opposite behavior in the phosphate deposits from Jordon and Kola, which are enriched in LREEs (except for La) and depleted in HREEs.
Cigarette smoking is documented source of human internal intake of toxic trace and heavy metals. ... more Cigarette smoking is documented source of human internal intake of toxic trace and heavy metals. However, data about tobacco-derived products such as moassel/tabamel and jurak, used in the growingly popular shisha (narghile, hookah), have been scarce and scattered. In these conditions, the objective of this study, the first ever carried out on this scale, was to investigate the elemental contents of moassel and jurak and compare it with that of other tobacco products. Representative samples from 3 different moassel brands were collected. Concentration of 34 elements was measured using the Inductively Coupled Plasma Mass Spectrometer (ICP-MS). Results show that trace elements are much more abundant in cigarette tobacco than in shisha moassel. A wide range of variations was observed. For instance, the levels of As, Cd and Ni (mg kg -1 ) were: 1.59, 1.0 and 0.146; 1.45, 0.5 and 0.075; 3.5, 5 and 0.63; for, respectively: cigarette, moassel and jurak. Since shisha smoking is continuously targeted by antismoking groups as a "global epidemic", a public health priority should be the design of culturally tailored products (for instance resins prepared from local plants to be mixed with the water of the pipes) based on well-established harm reduction techniques.
In this study, uranium concentrations (ppm) and the natural activity ratios ( 235 U/ 238 U) in 6 ... more In this study, uranium concentrations (ppm) and the natural activity ratios ( 235 U/ 238 U) in 6 representative samples of uranium ore samples were analyzed. The samples were collected from Gattar II ore site, which is located at the Red Sea northeastern desert of Egypt. The samples were measured using HPGe gamma ray detector (non-destructive technique) based on the measurement of the emitted gamma rays of uranium by using the photo peaks 163.33 keV for 235 U to avoid the overlapping with 186 keV of 226 Ra, and the 1001.03 keV photo peak of 234m Pa daughter for 238 U concentration respectively. The uranium concentrations of the same analyzed samples were determined using ICP-MS (destructive technique) for comparison. Sharp correlation (R 2 =0.9881) was found between uranium concentration measured by non-destructive gamma ray spectrometry and that measured by destructive ICP-MS for the same analyzed samples.
The coast of the Gulf of Aqaba is subjected to several sources of pollution due to several activi... more The coast of the Gulf of Aqaba is subjected to several sources of pollution due to several activities occurring at the coastal area. The activities vary between industrial, tourist and other development aspects at the Jordanian coastline of the Gulf of Aqaba. Phosphate industry has been considered a major source polluting the marine environment. According to official reports, 4-7 million tons of raw phosphate is exported through the Gulf of Aqaba. During transportation and loading, a small proportion of this enters the waters of the Gulf. Phosphate dust has also been considered another source of nutrients loading to the Gulf. 19 sediment samples were collected along the Saudi Gulf coastline, from the Saudi-Jordan border down to the end of the Gulf at Tiran Strait. Measurements of the activity concentrations of 226 Ra, 232 Th, 40 K and 137 Cs in Bq/kg (in dry weight) of the collected samples were carried out using gamma-ray spectrometry based on a highly pure germanium coaxial detector (HPGe). The concentrations of 238 U and 232 Th were also determined using ICP-MS technique. The average specific activities for 226 Ra, 232 Th, 40 K and 137 Cs were found to be 11.4 7 1.5, 22.5 7 3.7, 641.1 761.3 and 3.5 7 0.7 Bq/kg, respectively. The results show that the mean activity of 226 Ra and 232 Th is lower than the world average of 25 Bq/kg for both of them, whereas the mean value for 40 K is about double the world average of 370 Bq/kg. The presence of 137 Cs in the analyzed samples is low in most locations. The mean concentrations of 238 U and 232 Th in the study area are 1.2 and 5.4 mg/kg, respectively, and the ratio 238 U/ 232 Th is 0.2, which is lower than the global ratio of 0.3. The ratio of 226 Ra/ 228 Ra was found to decrease southwards in the direction of Tiran Strait, away from the phosphate industry in Jordan. Mean values for radium equivalent, absorbed dose, annual effective dose, external and internal hazard index and representative level index were determined as: 92.9 Bq/kg, 45.6 nGy/h, 56.0 mSv/y, 0.13, 0.28 and 0.73, respectively.
Clays are among the most important industrially used minerals. Three potential clay mineral minin... more Clays are among the most important industrially used minerals. Three potential clay mineral mining sites in Saudi Arabia were chosen, and 21 clay deposit samples were collected. The activity concentrations (average+ + + + +standard deviation) of the naturally occurring radioactive materials (NORMs), 238 U, 226 Ra, 232 Th, 228 Ra and 40 K, were 49+ + + + +20, 47+ + + + +23, 34+ + + + +11, 40+ + + + +20 and 751 Bq kg 21 , respectively. The radiation dose assessments (e.g., absorbed dose rate, nGy h 21 ; effective dose equivalent, mSv y 21 ; and effective dose rate due to dust inhalation, mSv y 21 ) and hazardous indices (e.g., radium equivalent [Ra-eq] value, external hazardous index [H ex ], internal hazardous index [H in ] and representative gamma level [I g ]) were calculated. The wide variations in the activity concentrations of the NORMs according to sampling region could be due to the origen of the geological formation and the geochemical behaviour of the NORMs. Based on calculated hazardous (external and internal) indices, there were no expected radiological hazardous impacts of using clay deposits as building materials.
The Red Sea is a deep semi-enclosed and narrow basin connected to the Indian Ocean by a narrow si... more The Red Sea is a deep semi-enclosed and narrow basin connected to the Indian Ocean by a narrow sill in the south and to the Suez Canal in the north. Oil industries in the Gulf of Suez, phosphate ore mining activities in Safaga-Quseir region and intensified navigation activities are non-nuclear pollution sources that could have serious radiological impacts on the marine environment and the coastal ecosystems of the Red Sea. It is essential to establish the radiological base-line data, which does not exist yet, and to investigate the present radio-ecological impact of the non-nuclear industries to preserve and protect the coastal environment of the Red Sea. Some natural and man-made radionuclides have been measured in shore sediment samples collected from the Egyptian coast of the Red Sea. The specific activities of 226 Ra and 210 Pb ( 238 U) series, 232 Th series, 40 K and 137 Cs (Bq/kg dry weight) were measured using gamma ray spectrometers based on hyper-pure germanium detectors. The specific activities of 210 Po ( 210 Pb) and uranium isotopes ( 238 U, 235 U and 234 U) (Bq/kg dry weight) were measured using alpha spectrometers based on surface barrier (PIPS) detectors after radiochemical separation. The absorbed radiation dose rates in air (nGy/h) due to natural radionuclides in shore sediment and radium equivalent activity index (Bq/kg) were calculated. The specific activity ratios of 228 Ra/ 226 Ra, 210 Pb/ 226 Ra, 226 Ra/ 238 U and 234 U/ 238 U were calculated for evaluation of the geo-chemical behaviour of these radionuclides. The average specific activity of 226 Ra ( 238 U) series, 232 Th series, 40 K and 210 Pb were 24.7, 31.4, 427.5 and 25.6 Bq/kg, respectively. The concentration of 137 Cs in the sediment samples was less than the lower limit of detection. The Red Sea coast is an arid à Corresponding author. Present address: region with very low rainfall and the sediment is mainly composed of sand. The specific activity of 238 U, 235 U and 234 U were 25.3, 2.9 and 25.0 Bq/kg. The average specific activity ratios of 226 Ra/ 228 Ra, 210 Pb/ 226 Ra and 234 U/ 238 U were 1.67, 1.22 and 1.0, respectively.
Phosphate and environmental samples were collected from Abu Tartor phosphate mine and the surroun... more Phosphate and environmental samples were collected from Abu Tartor phosphate mine and the surrounding region. The activity concentration of 226 Ra ( 238 U) series, 232 Th series and 40 K were measured using a gamma-ray spectrometer. The activities of uranium isotopes ( 238 U, 235 U and 234 U) and 210 Pb were measured using an alpha spectrometer and a low-background proportional gas counting system, respectively, after radiochemical separation. The results are discussed and compared with the levels in phosphate rocks from different countries. It seems that the Abu Tartor phosphate deposit has the lowest radioactivity level of exploited phosphate of sedimentary origen. 226 Ra/ 238 U, 210 Pb/ 226 Ra, 234 U/ 238 U and 226 Ra/ 228 Ra activity ratios were calculated and are discussed. The radioactivity levels in the surrounding region and the calculated exposure dose (nGy/h) will be considered as a pre-operational baseline to estimate the possible radiological impacts due to mining, processing and future phosphate industrial activities. To minimize these impacts, the processing wastes should be recycled to the greatest possible extent. #
Under the Egyptian program for radiation safety and control, airborne radioactivity measurements ... more Under the Egyptian program for radiation safety and control, airborne radioactivity measurements and radiological dose assessment were conducted in some phosphate and uranium mines. Abu-Tartor mine is one of the biggest underground phosphate mines in Egypt. Airborne radioactivity, radon ( 222 Rn) and its short-lived decay products (progenies) and thoron ( 220 Rn), were measured in selected locations along the mine. The environmental gamma and workers dose equivalent rate (mSv/y) were measured inside and outside the mine using thermo-luminescence dosimeters (TLD). The results were presented and discussed. The calculated annual effective dose due to airborne radioactivity is the main source of occupational exposure and exceeding the maximum recommended level by ICRP-60 inside the mine tunnels. A number of recommendations are suggested to control the occupational exposures. #
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