Présence et devenir des médicaments dans les eaux usées urbaines, une analyse bibliographique

Depuis quelques années, la présence de substances pharmaceutiques a été observée dans les milieux aquatiques y compris dans l’eau potable. Les principales sources de dispersion de ces composés dans l’environnement sont les stations d’épuration des eaux usées (STEP). Une analyse de la littérature publiée sur le sujet est proposée. Ce sont les analgésiques/anti-inflammatoires, les hypocholestérolémiants, les cytostatiques et les bêta-bloquants qui présentent les concentrations les plus élevées en entrée de station d’épuration. Malgré des rendements d’élimination quelquefois très élevés, les concentrations de ces groupes de médicaments restent non négligeables dans les effluents de stations.Les antibiotiques forment un des plus importants groupes de médicaments à cause de leur niveau de consommation, de leur fréquence de détection dans les milieux aquatiques et de leur action spécifique sur les bactéries, notamment celle potentiellement néfaste qu’ils peuvent avoir sur les bactéries mises en oeuvre dans les systèmes de traitement biologique des eaux résiduaires urbaines. Globalement, la charge en antibiotiques est faible dans les eaux usées urbaines mais elle est forte dans les effluents des hôpitaux. Les rendements d’élimination sont, quant à eux très variables, allant de 0 % pour le nitrothiazole à 95 % pour la tétracycline.For several years, the occurrence of pharmaceutical substances in the aquatic environment, and even in drinking water, has been a source of concern. The main sources of dispersion of these substances are wastewater treatment plants (WWTP). An analysis of the available literature on this topic is proposed. Analgesic, anti-inflammatory, anti-cholesterol and cytostatic drugs as well as beta-blockers are the substances that can be found in the highest concentrations in plant influents. In spite of elimination yields that can be very high, their concentrations in plant effluents can remain non-negligible. Antibiotics are one of the most important drug classes, due to their large consumption, their prevalence in aquatic systems and their specific action on bacteria, especially on those used in urban wastewater treatment biosystems. Globally, antibiotic concentrations in urban wastewater are normally low but they can be high in hospital wastewater. Elimination yields are very variable, ranging from a low of 0% for nitrothiazole to 95% for tetracycline

Investigating the Efficiency of Functionalized PAMAM-GO Nano-Composite for Nitrate Removal from Aqua Solutions

Due to the high solubility of nitrate in water, conventional treatment methods fail to remove it. This research investigated for the first time in national and global level, the efficiency of functionalized PAMAM-Go nanocomposite for nitrate removal from aquatic solutions. GO was synthesized by modified Hummers method. AFM images were used to characterize the GO and the AGO. Experiments were performed in a batch reactor and the main factors of pH, reaction time, and concentration of PAMAM_GO were investigated. The highest removal efficiency was obtained as 84% at 5 mL/L functionalized PAMAM_GO, pH of 3 and 25 min reaction time. The results showed that nitrate removal by functionalized PAMAM-Go nanocomposite is directly correlated with nanocomposite concentration and contact time while it is inversely correlated with pH and initial concentration of nitrate. It seems that ion exchange between nitrate and chloride is the main mechanism of nitrate removal by functionalized PAMAM_GO nano composite according to functionalization of PAMAM-Go using hydrochloric acid. This method can be used as a suitable method for in situ treatment of nitrate and many  pollutants in water and wastewater, due to its easy operation, no need for high levels of expertise and sophisticated equipment, no need for large space of construction, low initial investment, low price, availability of raw materials, simple synthesis of graphene oxide and  easy  to functionalize

Designing a Model for Explaining Media Literacy in the Secondary Education System of Iran (Research Based on Grounded Theory)

The promotion of media literacy is due to its scientific and organized research. The main role that media literacy plays in this is the main topic of the present article, which has been done in order to provide a model for explaining media literacy in high school. The research method is document mining and theory based on data (basic theory) and applied research, and qualitative in terms of data type in terms of descriptive implementation. The statistical population of the present study consists of two groups: first, media literacy specialists, educational planners and media literacy teachers who participated in specialized meetings, from which interviews were conducted to determine the elements for designing the desired model, and second, media literacy experts used. Sample size was used for interviewing 12 people for model validation of 35 people. The analysis method consists of three stages of open, axial and selective coding and is organized in the form of basic theory in the form of a network of basic themes. Findings show that the model includes a comprehensive theme and 7 organizing mechanisms. Which is emphasized in education and programming of media literacy book.1-Management mechanisms,2-Education and teaching mechanisms, 3-Structure reform mechanisms,4-Mechanisms of necessary competencies to create change in media literacy, 5-Learning mechanisms, 6- Mechanism for paying attention to the quality of education and 7- Mechanisms of developments and challenges facing media literacy education. Findings indicate that media literacy has two important themes ,which are considered as influential factors in the lives of audiences

Efficiency Evaluation of Nitrate Removal from Synthetic Solutions by Dendrimer- Graphene Oxide Nano-Composite Activated with HCl

High soluability of nitrate ions in water cause the dysfunction of many existing treatment methods in the removal of this very dangerous ion from aqueous media. On the other hand,  due to the need for in situ treatment methods, in particular for groundwater, the replacement of old inefficient methods with new compounds is required. In this study, for the first time, the efficiency of activated dendrimer- graphene oxide for nitrate removal from an aquatic solution was investigated. Experiments were performed in a batch reactor and the main factors of pH, reaction time, and concentration of PAMAM-GO were investigated. The highest removal efficiency was obtained as 90% at 0.025mg/L activated dendrimer- graphene oxide, pH of 7.5 and 15 min reaction time. The results showed that nitrate removal by activated dendrimer-graphene oxide is correlated with nanocomposite concentration, contact time, pH and initial concentration of nitrate. It seems that ion exchange between nitrate and chloride is the main mechanism of nitrate removal by activated dendrimer-graphene oxide according to functionalization of activated dendrimer-graphene oxide using hydrochloric acid. This method can be used as a suitable method for in situ removal of nitrate from water and wastewater due to the desirable ability of the nanocomposite and its optimal compatibility with the environment

Environmental Risk Assessment of Selected Antibiotics in Iran

In recent years the increasing use of pharmaceuticals and personal-care products (PPCPs), especially antibiotics, has become a particular concern because of their undesirable potential ecological and human health effects. This study presents an environmental risk assessment for the aquatic environment of some frequently used antibiotics in Iran in three stages including; a short literature review about antibiotic consumption in Iran, a comprehensive estimation regarding acute toxicity of selected antibiotics and finally calculation of Risk Quotient (RQ) using the predicted environmental concentration (PEC) and the predicted no-effect concentration (PNEC). According to recently published data, the consumption of antibiotics in Iran is several times greater than European countries and in case of antibiotics (e.g. Penicillin) is approximately 10 times greater than Scandinavian region. The calculated PECs were ranged from 0.0071 to 0.8570 and the PNECs value based on ecotoxicity data was found for all studied antibiotics (varied from 0.0037 to 177). The RQ exceeded one for Amoxicillin, Penicillin G, Sulfamethoxazole, and Erythromycin. Amoxicillin has the highest risk to aquatic organisms based on this study. With respect to the emergence of microbial resistance, it is important to begin monitoring the most frequently used antibiotic

Investigation of concentration polarization in a cross-flow nanofiltration membrane: Experiment and CFD modelling

Numerous researches have been investigated on the mass transfer phenomena and hydrodynamics for the fluid in the vicinity of the membrane surface by the mathematical modelling and simulation. Due to complexities involved in solving transport phenomena within membranes, the application of CFD simulation study for determining the concentration polarization (CP) profile in the membrane channel is limited. In this study, a 2D CFD modelling and simulation of CP phenomena in nanofiltration of an aqueous solution of MgSO47H2O in a vertical spacer-filled flat sheet membrane module was presented. A response surface methodology (RSM) statistical analysis has been designed in order to fully capture effects of variations of the feed liquid flow and the transmembrane pressure (TMP) on the permeate flux and concentration. It was also shown that increasing TMP or the liquid flow rate led to enhancing the permeate flux while increasing the feed concentration decreased it. The simulated results were validated and compared with the available experimental data, showing a satisfactory agreement. Eventually, the mass transfer coefficient derived from CFD simulations and calculated from Sherwood empirical relationships were compared which showed 10% and 33% difference in lower and higher liquid flow rates, respectively

Prioritisation of pharmaceuticals based on risks to aquatic environments in Kazakhstan

Over the last 20 years, there has been increasing interest in the occurrence, fate, effects and risk of pharmaceuticals in the natural environment. However, we still have only limited or no data on ecotoxicological risks of many of the active pharmaceutical ingredients (APIs) currently in use. This is partly due to the fact that the environmental assessment of an API is an expensive, time-consuming and complicated process. Prioritisation methodologies, that aim to identify APIs of most concern in a particular situation, could therefore be invaluable in focusing experimental work on APIs that really matter. The majority of approaches for prioritising APIs require annual pharmaceutical usage data. These methods cannot therefore be applied to countries, such as Kazakhstan, which have very limited data on API usage. This paper therefore presents an approach for prioritising APIs in surface waters in information-poor regions such as Kazakhstan. Initially data were collected on the number of products and active ingredients for different therapeutic classes in use in Kazakhstan and on the typical doses. These data were then used alongside simple exposure modelling approaches to estimate exposure indices for active ingredients (about 240 APIs) in surface waters in the country. Ecotoxicological effects data were obtained from the literature or predicted. Risk quotients were then calculated for each pharmaceutical based on the exposure and the substances ranked in order of risk quotient. Highest exposure indices were obtained for benzylpenicillin, metronidazole, sulbactam, ceftriaxone and sulfamethoxazole. The highest risk was estimated for amoxicillin, clarithromycin, azithromycin, ketoconazole and benzylpenicillin. In the future, the approach could be employed in other regions where usage information are limited. This article is protected by copyright. All rights reserved

Pharmaceutical substances and urban wastewater. I, Literature survey. II, Effect of two macrolide antibiotics on activated sludge

Les principaux points de dispersion des composés pharmaceutiques dans l’environnement sont les stations d’épuration des eaux usées. A partir de l’analyse de la base de données constituée au cours de ce travail, les quantités de ces composés trouvées dans ces installations peuvent être directement liées à celles de médicaments consommés. La situation, quant à leur élimination de la phase liquide, est contrastée. Ainsi certaines hormones sont éliminées avec des rendements importants mais d’autres ne le sont pas du tout. Les produits radio-contrastants à base d’halogènes et notamment d’iode, soupçonnés d’être cancérogènes, sont majoritairement non biodégradables. Les effets d’antibiotiques sur les boues activées ont été plus particulièrement étudiés du fait de leur consommation, de leur présence dans les milieux aquatiques et de leur action spécifique sur les bactéries. Des expériences permettant d’évaluer la toxicité de ces principes actifs ont été conduites sur des boues activées en réacteur discontinu, avec un suivi de la morphologie des flocs par analyse d’images de microscopie optique. Il a été ainsi observé que, selon la concentration utilisée, l’érythromycine et la tylosine, macrolides largement utilisés respectivement en médecine humaine et vétérinaire, inhibent l’élimination de la pollution organique et dégradent l’ensemble de la biomasse. Ces antibiotiques ont également un effet néfaste sur le métabolisme de l’azote, qu’il s’agisse de l’ammonification, de la nitritation et de la nitratationThe main sources of dispersion of pharmaceutical substances in environment are wastewater treatment plants. Based on the analysis of the database built during this project, the amounts of pharmaceutical substances found in plants can be directly related to the amount consumed. Regarding their elimination from the liquid phase, the situation is very disparate. The elimination yield of hormones can be null or very large. Halogen-based X-ray contrast media (or AOX) are mainly non biodegradable. The effects of antibiotics on activated sludge have been especially investigated due to their consumption, presence in aquatic environment and specific action on bacteria. Batch tests have been performed to evaluate the toxicity of these active pharmaceutical ingredients on activated sludge. Sludge morphology was monitored by analysis of light microscopy images. Depending upon the applied dose, erythromycin and tylosin, two macrolides widely used for human and animal health care, inhibit the elimination of organic pollution and damage biomass. These antibiotics have a deleterious effect on ammonification, nitritation and nitratatio

Composés pharmaceutiques et eaux usées urbaines. I, Analyse bibliographique. II, Effet de deux antibiotiques de type macrolide sur les boues activées

The main sources of dispersion of pharmaceutical substances in environment are wastewater treatment plants. Based on the analysis of the database built during this project, the amounts of pharmaceutical substances found in plants can be directly related to the amount consumed. Regarding their elimination from the liquid phase, the situation is very disparate. The elimination yield of hormones can be null or very large. Halogen-based X-ray contrast media (or AOX) are mainly non biodegradable. The effects of antibiotics on activated sludge have been especially investigated due to their consumption, presence in aquatic environment and specific action on bacteria. Batch tests have been performed to evaluate the toxicity of these active pharmaceutical ingredients on activated sludge. Sludge morphology was monitored by analysis of light microscopy images. Depending upon the applied dose, erythromycin and tylosin, two macrolides widely used for human and animal health care, inhibit the elimination of organic pollution and damage biomass. These antibiotics have a deleterious effect on ammonification, nitritation and nitratationLes principaux points de dispersion des composés pharmaceutiques dans l'environnement sont les stations d'épuration des eaux usées. A partir de l'analyse de la base de données constituée au cours de ce travail, les quantités de ces composés trouvées dans ces installations peuvent être directement liées à celles de médicaments consommés. La situation, quant à leur élimination de la phase liquide, est contrastée. Ainsi certaines hormones sont éliminées avec des rendements importants mais d'autres ne le sont pas du tout. Les produits radio-contrastants à base d'halogènes et notamment d'iode, soupçonnés d'être cancérogènes, sont majoritairement non biodégradables. Les effets d'antibiotiques sur les boues activées ont été plus particulièrement étudiés du fait de leur consommation, de leur présence dans les milieux aquatiques et de leur action spécifique sur les bactéries. Des expériences permettant d'évaluer la toxicité de ces principes actifs ont été conduites sur des boues activées en réacteur discontinu, avec un suivi de la morphologie des flocs par analyse d'images de microscopie optique. Il a été ainsi observé que, selon la concentration utilisée, l'érythromycine et la tylosine, macrolides largement utilisés respectivement en médecine humaine et vétérinaire, inhibent l'élimination de la pollution organique et dégradent l'ensemble de la biomasse. Ces antibiotiques ont également un effet néfaste sur le métabolisme de l'azote, qu'il s'agisse de l'ammonification, de la nitritation et de la nitratatio

Composés pharmaceutiques et eaux usées urbaines. I, Analyse bibliographique. II, Effet de deux antibiotiques de type macrolide sur les boues activées

Les principaux points de dispersion des composés pharmaceutiques dans l environnement sont les stations d épuration des eaux usées. A partir de l analyse de la base de données constituée au cours de ce travail, les quantités de ces composés trouvées dans ces installations peuvent être directement liées à celles de médicaments consommés. La situation, quant à leur élimination de la phase liquide, est contrastée. Ainsi certaines hormones sont éliminées avec des rendements importants mais d autres ne le sont pas du tout. Les produits radio-contrastants à base d halogènes et notamment d iode, soupçonnés d être cancérogènes, sont majoritairement non biodégradables. Les effets d antibiotiques sur les boues activées ont été plus particulièrement étudiés du fait de leur consommation, de leur présence dans les milieux aquatiques et de leur action spécifique sur les bactéries. Des expériences permettant d évaluer la toxicité de ces principes actifs ont été conduites sur des boues activées en réacteur discontinu, avec un suivi de la morphologie des flocs par analyse d images de microscopie optique. Il a été ainsi observé que, selon la concentration utilisée, l érythromycine et la tylosine, macrolides largement utilisés respectivement en médecine humaine et vétérinaire, inhibent l élimination de la pollution organique et dégradent l ensemble de la biomasse. Ces antibiotiques ont également un effet néfaste sur le métabolisme de l azote, qu il s agisse de l ammonification, de la nitritation et de la nitratationThe main sources of dispersion of pharmaceutical substances in environment are wastewater treatment plants. Based on the analysis of the database built during this project, the amounts of pharmaceutical substances found in plants can be directly related to the amount consumed. Regarding their elimination from the liquid phase, the situation is very disparate. The elimination yield of hormones can be null or very large. Halogen-based X-ray contrast media (or AOX) are mainly non biodegradable. The effects of antibiotics on activated sludge have been especially investigated due to their consumption, presence in aquatic environment and specific action on bacteria. Batch tests have been performed to evaluate the toxicity of these active pharmaceutical ingredients on activated sludge. Sludge morphology was monitored by analysis of light microscopy images. Depending upon the applied dose, erythromycin and tylosin, two macrolides widely used for human and animal health care, inhibit the elimination of organic pollution and damage biomass. These antibiotics have a deleterious effect on ammonification, nitritation and nitratationNANCY-INPL-Bib. électronique (545479901) / SudocSudocFranceF