Study of Water and Sediment Quality in the Bay of Dakhla, Morocco: Physico-Chemical Quality and Metallic Contamination

The present study contributes to the evaluation of the impact of the various activities developed around the Bay of Dakhla in Morocco through the study of the physico-chemical quality of the waters and sediments of the Bay. For this purpose, a spatial and temporal monitoring of the physicochemical and metallic pollution indicator parameters was conducted between May 2014 and March 2015. The main physicochemical descriptors of water quality were monitored, namely: temperature, salinity, pH, dissolved O2, nutrients (ammonium, nitrites, nitrates, phosphates) and chlorophyll (a). A qualification of the waters of the Bay was drawn up based on water quality assessment grids. The quality of the sediments was assessed through the determination of granulometry, the total organic carbon content and the contents of the main metallic trace elements (cadmium, lead, mercury, chromium, copper and zinc). The results of the present study show the beginning of nutrient enrichment of the water bodies of the bay, especially the stations located near the urban area, where 1.83 mg l−1 of nitrates, 0.37 mg l−1 of phosphate and 7.42 μg l−1 of chlorophyll (a) were recorded. For the sediment, the maximum concentrations of metallic trace elements were recorded in the station near the harbour basin. These results allowed to establish a quality grid for the waters of the bay, generally qualified as “Good”, except for the sites located near the urban area for which the quality is qualified as “Average”. The sediment quality of the bay was assessed according to the criteria established by the Canadian Council of Ministers of the Environment. The levels of metallic trace elements remain below the toxicity thresholds, except for the sediments taken from the harbour basin

Quality of Moroccan Atlantic coastal waters: water monitoring and mussel watching

The quality of Moroccan Atlantic coastal wasters was monitored from 1993 to 1997 by measuring hydrological parameters (dissolved oxygen, suspended particulate matter, phosphates, and nitrates), and using the mussel Mytilus galloprovincialis as a quantitative bioindicator of cadmium, copper, manganese, and zinc contamination. Mean concentrations of dissolved oxygen and suspended particulate matter were indicative of the effects of urban and industrial discharges of wastewater, particularly at Mohammedia, Casablanca, Mehdiya, Jorf Lasfar and Safi. Stations receiving urban wastewater showed high nitrate concentrations, especially at Mehdiya, Rabat, Mohammedia, Casablanca and El Jadida. Metal concentrations in mussels showed significant variations depending on the station and sampling period. Jorf Lasfar and Safi had the highest mean concentrations for cadmium (8 and 7 μg·g–1 dry weight respectively) and copper (74 and 25 μg·g–1 dry weight). The relation between cadmium concentrations in mussels, and phosphate concentrations in water suggests that the processing of phosphate ores at these two sites is responsible for contamination. Mussels in the Mohammedia–Casablanca sector had the highest zinc concentrations (338–379 μg·g–1 dry weight), followed by those collected at Jorf Lasfar (267 μg·g–1 dry weight), and Sidi Moussa and Safi (290–301 μg·g–1 dry weight). The distribution of manganese concentrations, which were maximal in estuaries (up to 19 μg·g–1 dry weight), was indicative of terrigenous inputs. Seasonal variations in mussel metal concentrations were characterised by winter minima, and apparently related to the physiological cycle of the animal. With the exception of cadmium-contaminated areas, the quality of mussels on the Moroccan Atlantic coast is good with respect to food safety standards

Assessment of contamination by organochlorine pesticides and polychlorinated biphenyl’s from Oualidia lagoon water (Morocco)

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Addition of Chickpea Flour in Durum Wheat Flour Makes Tortilla More Nutritious and Palatable, and Technologically Acceptable

In order to contribute to the reduction of nutritional deficiencies in Morocco, this study was undertaken to develop a healthier tortilla with higher iron and protein, while maintaining adequate technological and sensory qualities. Composite durum wheat flour enriched with 20, 25, 30, and 35% chickpea flour was assessed for nutritional, functional, and technological properties. Then, we selected two composite blends of 75:25 and 70:30 of durum wheat and chickpea flours for making tortillas to study nutritional, technological, and sensorial qualities. In addition, we studied the effects of making and cooking process and storage time. Kruskal–Wallis and Mann—Whitney tests were used for data analysis, and GraphPad Prism was used to create graphs. The results showed that composite tortilla had significantly higher nutritional value than durum wheat tortilla, and the best ratio was 30% chickpea flour. At this ratio, the results showed the best cooking time and the best yellowness, but tortilla fluffiness and puffiness decreased. Tortilla processing significantly increased protein at 30% chickpea flour, while minerals except sodium, weight, and diameter decreased. Adding 30% chickpea flour to durum wheat tortilla improved flavor. Then, storage decreased the weight resulting in decreased flexibility, and sanitary quality was lost early for 30% chickpea flour. In conclusion, adding 30% chickpea flour to durum wheat flour results in a healthier and tastier tortilla, which should be consumed fresh

Trace metal distribution in pelagic fish species from the north-west African coast (Morocco)

Abstract In the current study, ten elements contents (Fe, Zn, Mn, Cu, Cr, Co, Ni, Cd, Pb and Hg) have been measured in muscle and liver of four pelagic fish species (Engraulis encrasicolus, Sardina pilchardus, Scomber japonicus and Trachurus trachurus) from the north-west African coast (South Atlantic Moroccan coast), collected during summer and autumn seasons (July and December 2013, respectively). Significant differences in metal contents were found between the different species (p < 0.05). Metals levels were also much higher in liver than those recorded in muscle tissues. The concentrations of Fe, Zn, Cd, Co, Cu and Pb were significantly higher in mackerel liver (p < 0.05).While, in muscle, anchovy presents a higher content of Mn, Cu, Cr, Ni and Pb. A high level of cadmium was recorded in liver of the different species which can be attributed to an anthropogenic source (phosphate industry) and to natural sources (upwelling activities). The main concentration of toxic elements (Cd, Pb and Hg) recorded in the four edible muscles of pelagic fish species, under study, were below the established values by the European Commission Regulations and show that their effect on the consumers health can be considered as negligible

Chemical contamination baseline in the Western basin of the Mediterranean sea based on transplanted mussels

The MYTILOS project aimed at drawing up a preliminary report on coastal chemical contamination at the scale of the Western Mediterranean (continental coasts of the Balearic Islands, Sicily, Sardinia, Corsica and Maghreb) based on a transplanted mussels methodology validated along the French coasts since 1996 by Ifremer and the Rhône Méditerranée & Corsica water board. MYTILOS is backed up by the INTERREG III B/MEDOC programme, the PNUE/PAM-MEDPOL and Rhône Méditerranée & Corsica water board. Three cruises (2004, 2005, 2006) have taken place to assess the first state of chemical contamination along the Western Mediterranean shores with the same methodology. Approximately 120 days were spent at sea deploying and retrieving 123 mussel bags. The results obtained for all studied contaminants were equivalent to those obtained along the French coast according the RINBIO network. These similarities relate to both the highest measured levels and background levels throughout the 123 stations. The areas of greatest impact were mainly urban and industrial centers and the outlets of major rivers, with a far higher midsea impact on the dilution of organic compounds than on metals. Metal levels measured in midsea zones were found to be similar to those in natural shellfish populations living along the coast. On a global scale we can observe that the contaminants levels in the Mediterranean Sea are in the same range as in other areas worldwide. Overall, the research demonstrates the reliability of this methodology for marine pollution monitoring, especially in the Mediterranean sea. © 2010 Springer Science+Business Media, LLC.Peer Reviewe

Chemical Contamination Baseline in the Western Basin of the Mediterranean Sea Based on Transplanted Mussels

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Western Mediterranean coastal waters-Monitoring PCBs and pesticides accumulation in Mytilus galloprovincialis by active mussel watching: the Mytilos project

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Low incidence of SARS-CoV-2, risk factors of mortality and the course of illness in the French national cohort of dialysis patients

International audienceThe aim of this study was to estimate the incidence of COVID-19 disease in the French national population of dialysis patients, their course of illness and to identify the risk factors associated with mortality. Our study included all patients on dialysis recorded in the French REIN Registry in April 2020. Clinical characteristics at last follow-up and the evolution of COVID-19 illness severity over time were recorded for diagnosed cases (either suspicious clinical symptoms, characteristic signs on the chest scan or a positive reverse transcription polymerase chain reaction) for SARS-CoV-2. A total of 1,621 infected patients were reported on the REIN registry from March 16th, 2020 to May 4th, 2020. Of these, 344 died. The prevalence of COVID-19 patients varied from less than 1% to 10% between regions. The probability of being a case was higher in males, patients with diabetes, those in need of assistance for transfer or treated at a self-care unit. Dialysis at home was associated with a lower probability of being infected as was being a smoker, a former smoker, having an active malignancy, or peripheral vascular disease. Mortality in diagnosed cases (21%) was associated with the same causes as in the general population. Higher age, hypoalbuminemia and the presence of an ischemic heart disease were statistically independently associated with a higher risk of death. Being treated at a selfcare unit was associated with a lower risk. Thus, our study showed a relatively low frequency of COVID-19 among dialysis patients contrary to what might have been assumed