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Assessment of Heavy Metals Pollution in Water and Sediments of Djendjen River, North Eastern Algeria
2018
Krika, Abderrezak | Krika, Fouad
Water and sediment samples have been collected from five different stations, located along Djendjen River between February and June, 2016 so that the concentrations of Cd, Ni, Zn, and Cu could be determined. The extent of the sediment pollution has been assessed, using the multiple pollution indices, namely Contamination Factor (CF), Pollution Load Index (PLI), and the geoaccumulation index (Igeo).The distribution of trace elements in water and sediment follows Ni>Zn>Cd>Cu and Zn>Ni>Cu>Cd, respectively. The water sample analysis from Djendjen River shows that the total concentrations of Cu, Ni, Cd, and Zn have been lower according to the references. In comparison, sediment mean metal concentrations with several environmental contamination parameters, like probable effect level (PEC) and background levels, indicates that the concentrations of all investigated elements are lesser than PEC, except for Ni, but higher than the background levels. The Igeo values reveal that Cd has been the most accumulated compared to the other metals. Contamination Factor (CF) confirms that the sediment samples have been moderate in terms of all studied metals contamination. The Pollution Load Index (PLI) values have been above one (>1), indicating an advanced decline of the sediment quality.
Mostrar más [+] Menos [-]Assessment of annual air pollution levels with PM1, PM2.5, PM10 and associated heavy metals in Algiers, Algeria
2018
Talbi, Abdelhamid | Kerchich, Yacine | Kerbachi, Rabah | Boughedaoui, Ménouèr
Concentrations of particulate matter less than 1 μm, 2.5 μm, 10 μm and their contents of heavy metals were investigated in two different stations, urban and roadside at Algiers (Algeria). Sampling was conducted during two years by a high volume samplers (HVS) equipped with a cascade impactor at four levels stage, for one year sampling. The characterization of the heavy metals associated to the particulate matter (PM) was carried out by X-Ray Fluorescence analysis (XRF). The annual average concentration of PM1, PM2.5 and PM10 in both stations were 18.24, 32.23 and 60.01 μg m⁻³ respectively. The PM1, PM2.5 and PM10 concentrations in roadside varied from 13.46 to 25.59 μg m⁻³, 20.82–49.85 μg m⁻³ and 45.90–77.23 μg m⁻³ respectively. However in the urban station, the PM1, PM2.5 and PM10 concentrations varied from 10.45 to 26.24 μg m⁻³, 18.53–47.58 μg m⁻³ and 43.8–91.62 μg m⁻³. The heavy metals associated to the PM were confirmed by Scanning Electron Microscopy-Energy Dispersive X-Ray analyses (SEM-EDX). The different spots of PM2.5 analysis by SEM-EDX shows the presence of nineteen elements with anthropogenic and natural origins, within the heavy metal detected, the lead was found with maximum of 5% (weight percent). In order to determine the source contributions of PM levels at the two sampling sites sampling, principal compound analysis (PCA) was applied to the collected data. Statistical analysis confirmed anthropogenic source with traffic being a significant source and high contribution of natural emissions. At both sites, the PM2.5/PM10 ratio is lower than that usually recorded in developed countries. The study of the back-trajectories of the air masses starting from Sahara shows that desert dust influences the concentration and the composition of the PM measured in Algiers.
Mostrar más [+] Menos [-]Fatty acid composition, enzyme activities and metallothioneins in Donax trunculus (Mollusca, Bivalvia) from polluted and reference sites in the Gulf of Annaba (Algeria): Pattern of recovery during transplantation
2018
Rabei, Amina | Hichami, Aziz | Beldi, Hayet | Bellenger, Sandrine | Khan, Naim Akhtar | Soltani, Noureddine
The gulf of Annaba, the most important touristic and economic coastal zone located in Northeast Algeria, is contaminated by several pollutants from urban, agricultural, harbor and industrial activities. Elevated levels of heavy metals were detected in a locally prevalent edible mollusk Donax trunculus (Bivalvia, Donacidae) widely used as a sentinel species for the assessment of marine pollution. The present work aims to measure the difference between two localities, one being full of different pollutants (Sidi Salem) and the other being relatively clean (El Battah) and to evaluate the ability of D. trunculus to overcome the environmental stress during a transplantation experiment by a determination of fatty acid profile, the enzymes activities and the level of metallothioneins (MTs), a biomarker of metallic contamination. Adults of D. trunculus were collected at Sidi Salem (contaminated site) and transplanted into El Battah (reference site) for 21 days in cages (60 × 60 × 60 cm with a 2 mm mesh). Biochemical analyzes were conducted at different times (0, 7, 14 and 21 days). At 0-day experiment: the rate of the fatty acids, the enzymes activities and MT levels at the site of Sidi Salem (polluted site) were significantly different from those of El Battah. During the transplantation a gradual restoration of fatty acids rates, enzymes activities and MT levels was observed. At the end of the period of transplantation, the values are comparable to those of El Battah. A two-way ANOVA (time, site) on data revealed significant effects of time and site. Overally, D. trunculus is able to induce its detoxification system and to restore relatively rapidly the status of individuals from the reference site (El Battah).
Mostrar más [+] Menos [-]Levels and ecological risk assessment of heavy metals in surface sediments of fishing grounds along Algerian coast
2018
Ahmed, Inal | Mostefa, Boulahdid | Bernard, Angelleti | Olivier, Radakovitch
The level and the ecological risk assessment of heavy metals (Zn, Cu, Mn, Fe, Ni, Cr, V, As, Pb, Cd and Co) were evaluated in surface sediments from fifty-one stations along the Algerian coast. The main objective was to evaluate the risk that such metals may cause to the ecosystem, and thus the stations were choose in relation with the fishing trawlable areas of Algeria. The usual chemical indexes Geoaccumulation index (Igeo), Enrichment factor (EF) and Pollution Load Index (PLI) as well as potential ecological risk index reveal that the metal pollution along this coast is low, and is only related to As contents. Nevertheless, the concentrations of Ni, Cr and As exceed their respective ERL values (Effect range low) usually applied for Sediment Quality Guideline. However, Cr and Ni are mainly natural and cannot be related to anthropogenic inputs and their ecotoxicological levels as to be questioned.
Mostrar más [+] Menos [-]Polycyclic aromatic hydrocarbons, phthalates, parabens and other environmental contaminants in dust and suspended particulates of Algiers, Algeria
2018
Rabhi, Lyes | Lemou, Abdelkader | Cecinato, Angelo | Balducci, Catia | Cherifi, Nabila | Ladji, Riad | Yassaa, Noureddine
Chemicals such as polycyclic aromatic hydrocarbons (PAHs), phthalateesters, parabens, siloxanes and squalene, all of them classified as endocrine-disrupting chemicals (EDCs), have been reported to occur in all environmental compartments. The effects of EDCs on development, reproduction, growth, metabolism and obesity constitute a real public health issue. A list of EDCs (> 40 compounds) were characterised in total suspended particulates (outdoor soot: 92 samples) collected in July–September 2016 in an Algiers urban area; besides, settled indoor dusts (36 samples) were collected between November and December 2016 in schools, homes, manufacture and hospital of the same province. The analytical procedure consisted of ultrasonic bath extraction, column chromatography separation into fractions of different polarity and gas chromatographic-mass spectrometric processing. The total loads of phthalates ranging from 6.0 to 347 ng/m² (median, 26 ng/m²) were determined in indoor dust and 4.6 to 11.6 ng/m³ (median, 7.9 ng/m³) in outdoor soot; meanwhile, PAHs ranged from 12.1 to 108 ng/m² (median, 36 ng/m²) in indoor dust and ranged from 5.6 to 7.7 ng/m³ (median 5.7 ng/m³) in outdoor soot. Finally, illicit substances such as cocaine, cannabinol and Δ⁹-tetrahydrocannabinol were found to range from 0.5 to 11 pg/m³, 4.6 to 9.2 pg/m³ and 11 to 81 pg/m³, respectively, in outdoor soot.
Mostrar más [+] Menos [-]Physicochemical characterization and determination of chloramphenicol residues and heavy metals in Algerian honeys
2018
Mehdi, Yamina | Mutlaq, Ashraf | Al-Balas, Qosay | Azzi, Elhanafi | Bouadjela, Lamia | Taïbi, Nadia | Dakiche, Hadjira | Touati, Lounis | Boudriche, Lilya | Bachari, Khaldoun
The concentration of certain heavy metals in various foods (fruits, cereals, legumes, and bee products) produced in industrial and urban cities is increasing each year following industrial development. Quality of honey and its contamination by different polluting agents are related essentially to its production environment, or it can arise from beekeeping practices. In the present study, the determination of physicochemical properties: moisture, pH, total acidity, electric conductivity, hydroxymethylfurfural (HMF), sugars, and chloramphenicol (CAP) residues; the metal content by determination of two toxic metals levels: lead (Pb) and cadmium (Cd); and other trace elements: magnesium (Mg), iron (Fe), zinc (Zn), copper (Cu), and nickel (Ni) in 23 different honey samples collected from North regions of Algeria were investigated. The physicochemical properties and the metal contents were found within the ranges established by the international standards. For the antibiotic residues, only four honey samples are contaminated by CAP. Metals were found in non-significant values and are in safety baseline levels for human consumption except Mg which exceed the limits. These results suggested that honey could be used as an indicator to detect contaminating agents from the environment since bees are excellent sentinels for assessing environmental contamination because of their physiological and biological characteristics.
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