Publications by authors named "Merlina G"

Solar drying and liming are commonly used for sludge treatment, but little is known about their efficiency on antibiotics and Polycyclic Aromatic Hydrocarbons (PAHs) removal. This study aimed to investigate the removal of antibiotics and PAHs during solar drying of Limed Sludge (LS) and Non-Limed Sludge (NLS). Thus, organic matter fractionation and 3D fluorescence were used to assess the accessibility and the complexity of organic matter.

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The objective of this study was to investigate chemical, biological and eco-toxicological parameters of a compost produced through the co-composting of dewatered primary sludge (DPS) and date palm waste to evaluate in which extent it can exploited as a bio-fertilizer. DPS and date palm waste were co-composted in aerobic conditions for 210 days. Physico-chemical parameters were evaluated during composting (total organic carbon, total nitrogen, pH, available forms of phosphorus).

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Antibiotics persistence in the primary sludge can contribute to the emergence of these molecules in the environment and limit the agricultural recycling of sludge without any preliminary treatment. Composting is a widely used process for recycling sludges and then can contribute to the antibiotics removal. However, little interest is actually given to the evaluation of the persistence of some antibiotics families after the sludge co-composting and more particularly to the final compost valorization.

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In this work a fast analytical method for the determination of macrolides, tetracyclines and fluoroquinolones in a compost originating from a mixture of sewage sludge, palm waste and grass was developed by ultra-high performance liquid chromatography coupled to mass spectrometry (U-HPLC/MS). Antibiotics were extracted from compost by using the accelerated solvent extraction (ASE). The chromatographic separation was carried out on a T3 Cortecs C18 column using a mobile phase gradient mixture of water acidified with 1% of formic acid and acetonitrile.

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Wastewater treatment plant effluent, sludge and manure are the main sources of contamination by antibiotics in the whole environment compartments (soil, sediment, surface and underground water). One of the major consequences of the antibiotics discharge into the environment could be the prevalence of a bacterial resistance to antibiotic. In this review, four groups of antibiotics (Tetracyclines, Fluoroquinolones, Macrolides and Sulfonamides) were focused for the background on their wide spread occurrence in sludge and manure and for their effects on several target and non-target species.

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The objective of this study was to investigate thermal and physicochemical parameters of sewage sludge-palm waste mixtures contaminated by different families of antibiotics (tetracyclines, macrolides and fluoroquinolones) during co-composting. Sludge was spiked with chlortetracycline (CTC), oxytetracycline (OTC), roxithromycin (RXY), enrofloxacin (ENR) and ciprofloxacin (CIP). Antibiotics were spiked at a low level, medium level, high level and a control without antibiotics was conducted.

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Worldwide seagrass declines have been observed due to multiple stressors. One of them is the mixture of pesticides used in intensive agriculture and boat antifouling paints in coastal areas. Effects of mixture toxicity are complex and poorly understood.

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Olive mill wastewater (OMWW) is a by-product of the olive oil extraction industry. Its dumping creates severe environmental problems in the Mediterranean countries. The phytoxicity of OMWW is due to the phenolic substances and is evaluated through a genotoxicity method.

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Pesticides applied on crops are leached with rainfall to groundwater and surface water. They threat the aquatic environment and may render water unfit for human consumption. Pesticide partitioning is one of the pesticide fate processes in the environment that should be properly formalised in pesticide fate models.

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A new actinomycete strain designated TN256, producing antimicrobial activity against pathogenic bacteria and fungi, was isolated from a Tunisian Saharan soil. Morphological and chemical studies indicated that strain TN256 belonged to the genus Streptomyces. Analysis of the 16S rDNA sequence of strain TN256 showed a similarity level ranging between 99.

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The genotoxicity of quinolone and fluroquinolones was assessed using the micronucleus (MN) test on Vicia faba roots by direct contact exposure to a solid matrix. Plants were exposed to quinolones (nalidixic acid) and fluoroquinolones (ciprofloxacin and enrofloxacin) alone or mixed with artificially contaminated soils. Four different concentrations of each of these antibiotics were tested (0.

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Rising pesticide levels in streams draining intensively managed agricultural land have a detrimental effect on aquatic ecosystems and render water unfit for human consumption. The Soil and Water Assessment Tool (SWAT) was applied to simulate daily pesticide transfer at the outlet from an agriculturally intensive catchment of 1110 km(2) (Save river, south-western France). SWAT reliably simulated both dissolved and sorbed metolachlor and trifluralin loads and concentrations at the catchment outlet from 1998 to 2009.

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When heavy rainfall follows herbicide application, the intense surface runoff causes stream water contamination. Aquatic organisms are then briefly exposed to a complex mixture of contaminants. The aim of the present study is to investigate the genotoxic impact of such events on fish.

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Macrophyte communities play an essential role in the way freshwater ecosystems function. It is thus of great concern to understand how environmental factors, especially anthropogenic ones, influence their composition and diversity. The aim of this study was to examine whether the effects of a herbicide mixture (50% atrazine, 35% isoproturon, 15% alachlor) on single macrophyte species can be used to predict its impact at a community level.

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This study concerns a comparative analysis of the acridine orange and Giemsa staining procedures for the fish erythrocyte micronucleus assay. The goal was to optimize the assay in the context of field water monitoring. Fish (Carassius carassius) were exposed to a reference genotoxic agent, cyclophosphamide monohydrate 5 mg l(-1) for 2, 4, and 6 days before testing.

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Drinking water, cowpea and maize grains were sampled in some potentially exposed agro-ecological areas in Togo and analysed for their contamination by some common organochlorine pesticides. A total of 19 organochlorine pesticides were investigated in ten subsamples of maize, ten subsamples of cowpea and nine subsamples of drinking water. Analytical methods included solvent extraction of the pesticide residues and their subsequent quantification using gas chromatography-mass spectrometry (GC/MS).

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The in situ effect of biological activity on herbicide degradation was studied in sediment. Early diagenesis indicators of organic matter (OM) was selected to provide information on the presence and the kinetics of the various biotic and abiotic processes involved in the degradation of fresh organic matter, the vector of herbicides in sediment. Two tandem-coring samples were taken in the Malause reservoir, one in the hyperoxic zone (Tarn confluence, MT core) and the other in the central part, under the exclusive influence of the Garonne River (MG core), after having crossed a zone where the high intensity of abiotic processes is proven.

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The aim of the present study was to understand the effect of reservoir configurations on sediment pesticide fate. Two dams were selected on the River Garonne, in southwest France: Carbonne and Golfech, both with reservoirs subject to accumulation of herbicide-contaminated sediment. They are situated upstream and downstream respectively of an agricultural and urban area: the Mid-Garonne.

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Nitration reactions of aromatic compounds are commonly involved in different industrial processes for pharmaceutical, pesticide or military uses. For many years, most of the manufacturing sites used lagooning systems to treat their process effluents. In view of a photocatalytic degradation assay, the wastewater of a lagoon was investigated by using HPLC coupled with mass spectrometry.

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Olive-mill wastes represent a significant environmental problem in Mediterranean areas due to their important production during a short period of time. Their high polyphenol, lipid and organic acid concentrations turn them into phytotoxic wastes. This work examined the evolution of polyphenolic compounds during the composting of an olive-mill waste-wheat straw mixture by using quantitative (Folin-Ciocalteu) and qualitative (High Pressure Liquid Chromatography, HPLC) analyses.

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The level and fate of 16 polycyclic aromatic hydrocarbons (PAHs), targeted by the US Environmental Protection Agency (USEPA), has been studied over 90 days of composting of activated sludge with green waste, under a semi-arid climate. The total PAH calculated from the sum of the amounts of the 16 PAHs in the initial mixture of activated sludge and green waste, was lower than accepted European Union cut-off limits by about 0.48mgkg(-1).

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The composting process involves a succession of different communities of microorganisms that decompose the initial material, transforming it into a stable final product. In this work, the levels of phospholipid fatty acid (PLFA), neutral lipid fatty acid (NLFA) and sterol were monitored in compost versus time, as indicators of the activity of various microorganisms (Gram-positive or Gram-negative bacteria, fungi, etc.).

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Olive mill wastewater was treated by an aerobic bio-process at different values of pH (with or without addition of lime), for 45 days on a laboratory scale, to evaluate the reduction of the organic load. The lipid content showed an appreciable change in relation to the applied treatment both for total lipids and for the different fractions (neutral lipids, monoglycerides and phospholipids). 13C NMR spectroscopy was performed on initial and final samples both raw and after lipid extraction.

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The co-composting of olive oil mill wastes and household refuse was followed for 5 months. During the thermophilic phase of composting, the aerobic heterotrophic bacteria (AHB) count, showed a significant rise with a slight regression of fungal biomass. In the same way, phospholipid fatty acids PLFAs common in bacteria, showed a significant increase of hydroxyl and branched PLFAs.

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The treatment of olive mill waste water was studied on the laboratory scale. Physico-chemical analyses showed the final products had a mean pH of 5.4 without neutralisation and 5.

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