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We evaluated medical exposure and risk estimation during routine radio-diagnostic examinations in Agadir City during the year 2012. The frequency data were collected from four main Radiological dep...

Objective: This study aims to estimate the annual doses for personnel categories following their exposure to ionizing radiation during their occupation in the external radiotherapy department of the Center of Oncology and Hematology (COH) at Mohammed VI Hospital in Marrakech. Materials and Methods: Operational dosimeters PACK MGP DMC 3000 were used to measure the dose rates around the machines operating with ionizing radiation. In order to assess the reliability of the measurements made by these dosimeters, they were checked against measurements made at the same position by the Inspector detector. The annual effective dose was calculated by multiplying the average dose rate measured during a procedure by the overall treatment time throughout a year. Results: Regarding the reliability check of the measuring instrument, the recorded error is between 2 and 10% with an average of 7%. For personnel category A, the measured dose rate ranges from 0.066 to 0.083 µSv/h, with an average value of 0.075 µSv/h. For category B, it varies between 0.066 and 0.083 µSv, with an average value of 0.092 µSv/h. It is 0.074 µSv/h for category C. The annual dose for category A ranges from 0.089 to 0.113 mSv/year, with an average value of 0.101 mSv/year. For category B, it varies between 0.089 and 0.113 mSv/year, with an average value of 0.100 mSv/year. It is 0.100mSv/year for category C. Conclusion: The annual effective doses to personnel categories, assessed by this study, are very low compared to the regulatory standards set by the International Commission on Radiological Protection (ICRP). As a result, workers benefit from good radiation protection conditions within the Center of Oncology and Hematology at Mohammed VI Hospital in Marrakech.

We undertook an environmental isotope investigation of groundwater from the Turonian Aquifer of Tadla Basin in Morocco in order to confirm that this aquifer could be a potential site for palaeoclimate reconstruction. The collected groundwater samples were examined for stable oxygen, hydrogen and carbon isotope ratio, as well as noble gases (He, Ne, Ar, Kr, Xe), 14 C and 3 H concentration. The measured stable oxygen and hydrogen isotope values show that the Turonian aquifer has two recharge areas, one with a heavier isotopic signature from the unconfined aquifer in the northern region (the area of Boujad), while the other is characterised by lighter isotopic composition in the north-eastern to the south-western part of the basin (to the North from Kasba Tadla). The calculated noble-gas solubility temperatures of the confined part of the aquifer are 2 °C higher than the recent mean annual air temperature (19 °C). Radiocarbon ages obtained from running different versions of Ingerson-Pearson models indicated that the recharge of this water occurred during the Holocene. We conclude that the Turonian aquifer might be a potential place for Late-Pleistocene palaeoclimate reconstruction if the research area were extended in the direct of flow path towards the western part of the basin and towards the foothills of the Phosphates Plateau.

Background: Physicians use diver radiology technologies on a daily basis to diagnose stage and treat cancers with the goal of saving thousands of lives. The use of CT scans in medical diagnosis exposes patients to radiation doses higher than other radiological procedures. It is estimated that CT scans represent about 20% of radiological procedures and contribute about 80% to medical radiological exposure doses. Purpose: The purpose of this study is to estimate the doses delivered during abdominopelvic CT procedures in order to evaluate the biological effects in patients at the Mohamed VI University Health Centre in Oujda, Morocco.

The purpose of this study is to evaluate the patients’ radiation dose in three different modalities of CT scanners (64, 16 and 2 slices) and the biological effects during CT brain examinations.A total of 60 patients were examined in three different hospitals in Morocco. The data were collected from CT Brain examinations at of 20 CT scans per hospital. For each examination, we have reported CT acquisition parameters including the number of series, use of contrast medium; tube kV, tube current and rotation time, slice thickness as well as the displayed CT dose index (CTDIvol) and the Dose Length Product (DLP). Cancer and biological heredity risks were estimated using the International Commission on Radiological Protection (ICRP) conversion factors.The average dose values for CT brain for 2 slices was 305 ± 112 mGy.cm. The mean dose value for 16 slices was 716 ± 179 mGy.cm, while the average dose for 64 slices was 1136 ± 708 mGy.cm. The patient cancer risks per procedure ranged between 4 and 13 per 105 CT procedures. This risk is 4, 8 and 13 per 105 CT procedures for 2 slices, 16 slices and 64 slices respectively. The patient heredity risks varied between 1 and 5 per million CT procedures. It is 1, 3 and 5 for 2 slices, 16 slices and 64 slices respectively.Dual slice scanner delivered the least effective dose while 16 and 64 slice scanners delivered the highest effective dose. The dose values of this study were comparable to the international reference levels of CT examination. CT dose optimization protocol is not implemented in the Moroccan hospitals. These values could be used as our hospital's Dose Reference Levels (DRL) until a more detailed study survey can be conducted in Morocco for the establishment of the country's reference levels. Keywords: CT brain scan, DRL assessments, Radiation risks, Moroccan hospitals

Computed Tomography (CT) of Brain is a diagnostic device used to create detailed pictures of the skull, brain, paranasal sinuses, and eye sockets; however, patients are exposed to great radiation doses and the likelihood of a cancer occurrence and other biological effects is increased. The objectives of this study were to measure the patient radiation dose during a brain CT procedure and to assess the radiation dose and biological effects.The study was conducted in six radiology departments equipped with various CT machines calibrated according to international protocols. A total of 180 patients underwent brain examinations. The effective radiation dose, cancer and biological risks were estimated using the International Commission on Radiological Protection (ICRP) conversion factors.The effective dose for Brain CT procedure in Moroccan hospital varied between (0,80± 0,12) and (5,47± 1,51) mSv with an average value of (2,96± 0,67) mSv. The cancer risk per Brain procedure ranged between 44 and 301 with an average value of 163 per 1 million procedures. The hereditary risk per Brain procedure ranged between 2 and 11 with an average value of 6 per 1 million procedures. The effective dose and risk factors for brain CT scan examination are higher than the national averages for one third of our hospitals.The cancer and hereditary risks are significant during multiple image acquisition. The study revealed that 66% of the procedures with normal findings. However, staff should optimize the radiation dose during Brain procedures.

Purpose The goal of this pilot study was to estimate the doses delivered during of pelvimetry Computed Tomography (CT) procedures in order to establish local diagnostic reference level (DRL) of Ibn Sina Children's Hospital of Rabat. Materials and methods This study consisted of examining a total of 30 patients. All CT examinations were performed with a SIEMENS Somatom Sensation 64 CT with Automatic Exposure Control System. The data that collected for each diagnostic exam chosen included scanner acquisition parameters, number of series, use of the contrast medium, and rotation time as well as slice thickness, the displayed CT dose index (CTDIvol) and the Dose Length Product (DLP). Effective dose and DRL were evaluated using the International Commission on Radiological Protection (ICRP) conversion factor. Results The average age of women who have benefited from the pelvimetry CT scan is equal to 25.10 ± 4.75 years. Tube voltage (kV), tube current and rotation time were 110 (kV), 30 (mA) and 0,8 (s) respectively. The average displayed CT dose index CTDIvol were 2.15 ± 0.02 mGy. The average dose length product (DLP) was (55.97 ± 0.25) mGy cm. The average effective dose received by women pregnant during a pelvimetry CT scan was 0.84 ± 0.01 mSv. The foetal dose was 2.36 ± 0.02 mGy. The local DRL for this procedure was equal to 56.66 ± 2.15 mGy cm. Conclusion Our values are higher than the standards of some European countries. This first ever survey of CT practice in Ibn Sina Children's Hospital of Rabat confirmed the need to improved training of health professionals involved in computed tomography on factors affecting image quality and dose and protocols optimization.

The Shapash Nuclear Research Institute (SNRI) data book was issued by the International Atomic Energy Agency (IAEA) in 2013. The hypothetical facility data book describes the hypothetical site, which is divided into two areas: the low-security area, known as the administrative area, and the very high-security area, known as the protected area. The book contains detailed descriptions of each area’s safety and security measures, along with figures of multiple buildings in both areas, and also includes information about the site’s computer networks. This paper aims to identify security weaknesses related to the institute’s location, the Administrative Area (AA), the Protected Area (PA), and the Instrumentation and Control Technology system (ICT) within the SNRI and proposes corrective actions to improve the site’s security measures against malicious acts, based on the IAEA nuclear security series publications, and ultimately proposes a new layout for the whole site and the research reactor building presenting the changes made, using a software called Edraw Max.

Ct scans or Computed Tomography use X-rays to make detailed pictures of the area inside the body. CT brain examinations are used to diagnose the skull, brain, paranasal sinuses, eye sockets and other various head conditions. In the other side, if patients are exposed to greater radiation doses, it is more likely that they develop a cancer or biological effect. This study aims to measure the patient radiation dose during a brain CT procedure and to assess the radiation dose and biological effects.

This paper describes a method for the multielement determination of Ti, V, Cr, Co, Ni, As, Rb, Sr, Ba, Th, and U in water from the Bouregreg River (Morocco) by use of inductively coupled plasma mass spectrometry (ICP-MS). The distribution of trace elements in water samples of the Bouregreg River and its tributaries was determined by measurements at 10 sampling sites. The data obtained show that the spectrum of normalized concentrations with regard to concentrations found at the reference station (site AGL1) have rather identical forms for sites located downstream in the river, wheres a certain dispersal was observed for sites situated upstream in the river (BLH, KSK1, KSK2, and AGL2). The concentrations of most elements are particularly low at the reference station (site AGL1). The elements Co, As, and Rb show a maximum concentration at the site AGL2 situated downstream of Aguelmous and close to a public discharge; this is explained by an anthropogenic origin for the concentrations of these elements.

In this work, we report the measurement of uranium content in some natural formation samples in Morocco. Such results are used in several studies concerning the earth sciences and the environment such as geochronology, archaeology, geophysical and geophysical studies, and prospecting of radioactive pollution. The analyses were carried out on some natural deposits such as corals, fossil shells of mollusks, phosphates, travertines, lichens, and on impure carbonate deposits. Measurements were realized by alpha-spectrometry for fossil shells of mollusks, corals, travertines, and impure carbonates, by gamma spectrometry using a well detector with NaI scintillation for phosphates, and by neutron activation for lichens. Isotopic 234U/238U ratios were also measured and are discussed.

Instrumental neutron activation analysis (INAA), inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES) were used for the determination of major and trace elements in sediment samples of the Bouregreg river (Morocco). The reliability of the results was checked, by using IAEA Soil-7 certified reference material. Results obtained by the three techniques were compared to control digestions efficiencies. A general good agreement was found between INAA and both ICP-MS and ICP-AES after alkaline fusion (ICPf). The ICP-MS technique used after acid attack (ICPa) was satisfactory for a few elements. A principal component analysis (PCA) has been used for analyzing the variability of concentrations, and defining the most influential sites with respect to the general variation trends. Three groups of elements could be distinguished. For these groups a normalization of concentrations to the central element concentration (that means Mn, Si or Al) is proposed.

Purpose: As a way of prevention, we have measured the activities of uranium and radium isotopes (234U, 238U, 226Ra, 228Ra) for 30 drinking water samples collected from 11 wells, 9 springs (6 hot and 3 cold), 3 commercialised mineral water, and 7 tap water samples. Methods: Activities of the Ra isotopes were measured by ultra-gamma spectrometry using a low background and high efficiency well type germanium detector. The U isotopes were counted in an alpha spectrometer.Results: The measured Uranium and radium activities are similar to those published for other non-polluting regions of the world. Except in one commercialised gaseous water sample, and in two hot spring water samples, the calculated effective doses during one year are inferior to the reference level of 0.1 mSv/year recommended by the International Commission on Radiological Protection. Conclusion: These activities don't present any risk for public health in Morocco. The sparkling water of Oulmes is occasionally consumed as table water and waters of warm springs are not used as main sources of drinking water.

Summary In this work, radiochemical analysis results of 126 unrecrystallized coral samples from the Egyptian shoreline of northwestern Red Sea and 120 fossil mollusk shell samples from the Atlantic coast of Moroccan High Atlas at the North of Agadir City in Morocco are presented and discussed. The coral samples were collected in Egypt from the emerged coral reef terraces over 500 km from The Ras Gharib-Ras Shukeir depression (28°10') in the north to Wadi Lahami (north of Ras Banas, 24°10') in the south. The fossil mollusk shells were collected in Morocco from Agadir-Harbour in the south to Tamri village in the north extending over about 50 km. The statistical distributions of results (238U content, 234U/238U activity ratio and ages) obtained on the dated materials in the two different regions were compared for three fossil sea levels corresponding to three different climatic stages (Holocene, 5e, 7 and/or 9) in the aim to establish methodological criteria for judging validity of the measured ages. For corals, 238U content varies in narrow interval around the same average value of 3 ppm for the three sea levels, the calculated initial 234U/238U values are in agreement with the actual sea water ratio (1.15) with some values slightly higher than for the older sea levels. The obtained ages are in good agreement with the ages reported previously for the three emerged fossil sea levels on unrecrystallized corals by alpha spectrometry and by mass spectrometry. For mollusk shells, except for Holocene sea level, 238U and initial 234U/238U activity ratios vary for the older levels in wide intervals, independent of species and calcite contents of samples. The high 238U contents and 234U/238U activity ratio are due eventually to a post-incorporation of secondary uranium from sea water or from continental waters drained away rivers. This incorporation leads to a rejuvenation of mollusk shell ages and is responsible for the wide dispersion of their apparent ages according to the mode and the timing of uranium introduction.

Radiochemical results (234U,238U,226Ra and228Ra activities;234U/238U,228Ra/226Ra and226Ra/238U activity ratios) are reported for 31 drinking water samples collected from 8 wells, 12 hot mineral springs, 5 cold springs, and 6 tap water samples. Activities of the Ra isotopes were measured by gamma spectrometry using a low background and high efficiency well type germanium detector. The U isotopes were counted in an alpha spectrometer. The results show that238U activity varies between 4.46 and about 308 mBq l-1in wells, 0.59 and 17.88 mBq l-1in hot springs, 2.19 and 3.21 mBq l-1in cold springs, and between 2.5 and 15.70 mBq l-1in tap water samples.234U/238U activity ratio is generally higher than 1 which is the equilibrium activity ratio value in closed systems. It varies in the ranges 0.79-2.11 in wells, 0.97-7.39 in hot springs, 2.53-8.30 in cold springs, and 1.14-3.35 in tap water. Unlike well waters, spring waters show low238U activities and high234U/238U activity ratios. The highest activity of Ra measured in hot mineral water samples is about 150 and 352 times higher than the highest activity of Ra found in well waters and in cold springs, respectively.226Ra/238U activity ratios are in the ranges: 0.07-1.14 in wells, 1.79-2115 in hot springs, 0.86-4.79 in cold springs, and 0.18-5.61 in tap water samples. The data are similar to those published for other regions of the world.

Afin de comprendre la difficulte de datation des niveaux marins a l'aide des echantillons de coquilles de mollusques et d'essayer d'etablir des outils methodologiques pouvant aider a juger de la validite d'un âge 230Th /234U, nous confrontons 80 analyses radiochimiques d'echantillons de coquilles de mollusques preleves dans des plages marines fossiles situees entre 4 et 8 m par rapport au niveau de l'eau actuel. les niveaux ou ont ete faits les prelevements, analogues a ceux de la cote egyptienne de la Mer Rouge, sont senses appartenir au stade climatique 5e date a 122 ka environ. On note que les âges obtenus sont souvent rajeunis independamment du site, du taux de calcite, de la teneur en uranium et du rapport 234U/238U. Contrairement aux echantillons de coraux, le critere mineralogique ne peut pas etre utilise pour choisir les echantillons non recristallises, certaines coquilles de mollusques actuelles sont en aragonite, d'autres sont en calcite et d'autres contiennent les deux formes sans que les rapports de proportion en soient encore bien connus. Devant cette situation, nous avons multiplie les analyses sur des echantillons de coquilles de mollusques appartenant a plusieurs especes preleves aux memes endroits afin de comprendre le scenario de rajeunissement des âges et d'essayer d'etablir eventuellement des criteres methodologiques pouvant nous renseigner sur la validite de l'âge calcule. Des scenarios sur le mode d'incorporation de l'uranium et son role dans le rajeunissement de l'âge ont ete egalement imagines et discutes.

Rare earth elements (REE), define a group of fifteen chemical elements from lanthanum to lutetium (atomic numbers 57-71) characterized by similar chemical properties. To study their distribution in sediment samples of the Bouregreg river and its tributaries, 10 sampling sites have been chosen. The collected sediment samples were analysed by instrumental neutron activation analysis (INAA) using the Orphee and Osiris reactors of CEA Saclay (France). The chondritic normalisation curves show enrichment in light rare earth elements (LREE), a negative Eu anomaly in several samples, and a progressive depletion of heavy rare earth elements (HREE). Two hypotheses are discussed: the nature of parent rocks of these sediments and the phisico-chemical conditions of sedimentation especially complexation and oxydo-reduction phenomenons.

Purpose: To determine the activities of 226Ra and 228Ra in the reservoir and spring water samples respectively during the dry and the rainy seasons; and to calculate the annual intake Ii (Bq/y) for each type of water samples. Methods: Using both well calibrated Canberra NaI(Tl) and HPGe detector systems, it was possible to determine the average specific activity of those radium’s isotopes in water samples which were collected in 2010, from Reservoirs and springs in Cameroon central region including Ngoaekelle, Minboman, Etoudi and Njoungolo. Results: The average specific activity values obtained for 226Ra and 228Ra in reservoir water samples were 8.76 ± 3.50 BqL-1 and 0.64 ± 0.28 BqL-1 during the dry season and, 8.24 ±3.48 BqL-1 and 0.58 ± 0.24 BqL-1 during the rainy season respectively. For spring water, the average values were 3.50 ± 0.63 BqL-1 and below 0.0002 BqL-1 (detection limit of 228Ra in water) during the dry season; 3.20 ± 0.60 BqL-1 and below 0.0002 BqL-1 (detection limit of 228Ra in water) during the rainy season respectively. Assuming that the volume of drinking water for adult is 2.5 litres per day, the average annual intakes of 226Ra and 228Ra through ingestion in these water samples were 7702 Bq/y and 575 Bq/y for reservoir water; 2993 Bq/y and < 0.25 for spring water respectively. Conclusion: The results have indicated that the annual intake by the population of sampling region as a result of 226Ra in these drinking waters is 7.7 × 103Bq/y more than the maximum limit fixed by ICRP which is 7 × 103 Bq/y. There is a need for regular monitoring the radiological water quality aspect in this region.

Purpose: As a way of prevention, we have measured the volumic activities of indoor 222Rn and we have calculated the corresponding effective dose in some dwellings and enclosed areas in Morocco. Seasonal variation of Radon activities and Relationships between variation of these activities and some parameters such height, depth and type of construction were also established in this work.Methods: The passive time-integrated method of using a solid state nuclear track detector (LR-115 type II) was employed. These films, cut in pieces of 3.4 ´ 2.5 cm2, were placed in detector holders and enclosed in heat-scaled polyethylene bags.Results: The measured volumic activities of radon vary in houses, between 31 and 136 Bq/m3 (0.55 and 2.39 mSv/year) with an average value of 80 Bq/m3 (1.41 mSv/year). In enclosed work area, they vary between 60 Bq/m3 (0.38 mSv/year) in an ordinary area to 1884 Bq/m3 (11.9 mSv/year) at not airy underground level of 12 m. the relatively higher volumic activities of 222Rn in houses were measured in Youssoufia and khouribga towns situated in regions rich in phosphate deposits. Measurements at the geophysical observatory of Berchid show that the volumic activity of radon increases with depth, this is most probably due to decreased ventilation. Conclusion: The obtained results show that the effective dose calculated for indoor dwellings are comparable to those obtained in other regions in the word. The risks related to the volumic activities of indoor radon could be avoided by simple precautions such the continuous ventilation. The reached high value of above 1884 Bq/m3 don't present any risk for workers health in the geophysical observatory of Berchid because workers spend only a few minutes by day in the cellar to control and reregister data.

Activities and activity ratios of uranium and radium isotopes (234U, 238U, 226Ra, 228Ra, 234U/238U, 226Ra/238U, 228Ra/226Ra) have been determined for 15 wells, 14 hot springs, 7 cold springs and 11 rivers. Activities of the radium isotopes were measured by ultra gamma spectrometry using a low background and high efficiency well type germanium detector whereas those of uranium were counted in an alpha spectrometer. The minimal, maximal and average values are reported here for each water source. The obtained results show that, unlike well waters, the thermal spring waters present relatively low 238U activities and elevated 226Ra activities and 234U/238U activity ratios. Uranium and radium activities are similar to those published for other non polluting regions of the world.

Les activités des isotopes de l'uranium et du radium (234U,238U,226Ra,228Ra) ainsi que les rapports d'activité (234U/238U,226Ra/238U,228 Ra/226Ra) ont été mesurés, pour la première fois au Maroc, dans 15 échantillons d'eau de puits et 12 échantillons d'eau de sources thermales. Les résultats obtenus montrent que, contrairement aux eaux de puits, les eaux des sources thermales présentent des activités de238U relativement faibles et des activités de226Ra et des rapports234U/238U élevés. Les activités de l'uranium et du radium mesurées sont comparables à celles que l'on trouve habituellement dans d'autres régions non polluées du monde, elles sont inférieures aux limites maximales admissibles ce qui ne pose aucun risque pour la santé publique au Maroc., Activities and activity ratios of uranium and radium isotopes (234U,238U,226Ra,228Ra,234U/238U,226Ra/238U,228Ra/226Ra) have been determined, for the first time in Morocco, for 15 well water samples and 12 spring water samples. The obtained results show that, unlike well waters, the thermal spring waters present relatively low 238U activities and elevated226Ra activities and 234U/238U activity ratios. Uranium and radium activities are similar to those published for other non polluting regions of the world, they are inferior to the Maximum Contaminant Levels and don't present any risk for public health in Morocco.