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Kinetic and dynamic aspects of soil–plant–snail transfer of cadmium in the field
2008
Gimbert, Frédéric | Mench, Michel | Coeurdassier, Michaël | Badot, Pierre-Marie | de Vaufleury, Annette | Laboratoire Chrono-environnement (UMR 6249) (LCE) ; Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC) ; Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC) | Université Sciences et Technologies - Bordeaux 1 (UB) | Unité sous contrat biologie environnementale ; Institut National de la Recherche Agronomique (INRA)-Université de Franche-Comté (UFC) ; Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)
International audience
Afficher plus [+] Moins [-]Greening Through Industrial Relocation in Vietnam: The Case of Ho Chi Minh City
2008
Le Van Khoa | Ho, P.P.S.
Poly-aromatic hydrocarbon (PAH) inputs from the Rhône River to the Mediterranean Sea in relation with the hydrological cycle: Impact of floods | Influence du cycle hydrologique et des crues sur les apports en hydrocarbure HAP du Rhône à la Méditerranée
2008
Sicre, Marie-Alexandrine | Fernandes, M.B. | Pont, Didier | Paléocéanographie (PALEOCEAN) ; Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) | AQUATIC SCIENCES CENTRE AUS ; Partenaires IRSTEA ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Hydrobiologie (UR HYAX) ; Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF)
[Departement_IRSTEA]MA [TR1_IRSTEA]QSA / HYDRECO | International audience | The concentrations of dissolved and particulate polycyclic aromatic hydrocarbons (PAHs) were monitored in waters of the Rhône River (France) every fortnight for a full calendar year, from June 1994 to May 1995. All flood events occurring over the course of the experiment were sampled at higher frequency to better quantify the impact of these extreme hydrological episodes on the annual export of PAHs to the Mediterranean Sea. This time-series indicates that more than 90% of the annual load of particulate PAHs is transported during flood episodes, with 77% discharged during the course of only one extreme flood event occurring in November 1994. During these intense events, riverine particles are depleted in PAHs while at low river discharge particles are PAH-enriched. Dissolved PAHs were less variable and less abundant than adsorbed PAHs, consistently with the low solubility of these compounds.
Afficher plus [+] Moins [-]The "storm of the century" (December 1999) and the accidental escape of Siberian sturgeons (Acipenser baerii) into the Gironde estuary (Southwest France): an original approach for metal contamination | La "tempête du siècle" (decembre 1999) et l'échappement accidentel d'esturgeons sibériens (Acipenser baerii) dans l'estuaire de la Gironde (SO france) : un bioindicateur original de contamination métallique
2008
Maury-Brachet, Régine | Rochard, Eric | Durrieu, Gilles | Boudou, Alain | Environnements et Paléoenvironnements OCéaniques (EPOC) ; Observatoire aquitain des sciences de l'univers (OASU) ; Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) | Ecosystèmes estuariens et poissons migrateurs amphihalins (UR EPBX) ; Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF) | Université de Bordeaux (UB)
[Departement_IRSTEA]MA [TR1_IRSTEA]QSA / DYMECO | International audience | Goal, Scope and Background. The Gironde estuary is considered as a reference ecosystem with a large fish assemblage (75 species) and the presence of eleven diadromous species. However, geochemical studies and biomonitoring using oysters have shown high metal pollution levels. During the December 1999 hurricane, more than 5,000 young Siberian sturgeons (Acipenser baerii) accidentally escaped from a fish farm into the estuary, where this species had not been present until then. Methods. In 2002/2003, thirteen sturgeons were collected from the estuary and twelve were obtained from the fish farm, from the same initial batch. Analysis of five metals (cadmium, zinc, copper, lead, mercury) measured in the gills, muscle, liver and kidneys, revealed significantly higher levels of cadmium, lead and mercury in the sturgeon collected from the estuary compared with those from the fish farm. Results and Discussion. Metal analysis of the stomach contents of fish collected from the estuary and artificial food used in the fish farm indicated that dietary exposure might account for the differences observed. Nevertheless, metal concentrations in sturgeons that had spent about three years in the Gironde estuary may be considered low when compared with other species (mullets, eels) or with data in the literature regarding concentrations able to induce structural and functional perturbations in fish. As the introduced Siberian sturgeons live in the same place and feed on the same prey as the juveniles of the endangered A. sturio, our results indicate in the short term that this strictly protected species does not appear to be much affected by the polymetallic pollution in the Gironde estuary. Marked differences in the concentrations of three metals (Cd, Pb, Hg) were established in four organs (gills, liver, skeletal muscle, kidneys) of Siberian sturgeons between specimens that had accidentally escaped into the Gironde estuary (France) during the December 1999 hurricane and were collected in March/June 2003 and specimens from the same initial batch at the fish farm. Recommendations and Perspectives. Based on these results, a programme will be set up, with sampling campaigns carried out in the estuary every two years, with systematic monitoring of age in order to check the origin of individuals, in conjunction with sampling of sturgeon from the fish farm. This programme will complement other studies on several biological species representative of the main trophic levels in the estuary, especially the plankton component, benthic macroinvertebrates and oysters.
Afficher plus [+] Moins [-]Phosphorus removal by apatite in horizontal flow constructed wetlands: kinetics and treatment reliability
2008
Harouiya, N. | Molle, Pascal | Prost Boucle, S. | Liénard, A.
Phosphorus removal in constructed wetlands have received particular attention last decades by using specific materials promoting adsorption/precipitation mechanisms. Recent studies have shown interest in using apatite materials to promote P precipitation onto the particle surface. As previous trials were mainly done by lab experiments, this present study aims to evaluate the real potential of apatites to remove P from wastewater in pilots and a full-scale plant. Two different apatites have been studied in 1.5 m² pilots fed with wastewater from the outlet of a trickling filter. They were monitored to follow inlet/oulet flows, hydraulic gradient, meteorological conditions, pH, temperature, and redox potential. Treatment performances were evaluated by regular complete analysis (COD, BOD, SS, nitrogen and phosphorus forms, Ca) as well as PO4-P by a WTW online analyser. At the same time a full-scale experiment study have been done to point out P retention properties in real conditions over a 2 years period. P retention kinetics of two qualities of apatites are presented and discussed according to the temperature dependence. In this work apatite appears to have high retention capacity and is still an interesting way for P removal in constructed wetlands. However, other qualities of apatite must be studied for a better reliability of treatment.
Afficher plus [+] Moins [-]Treatment of septage in sludge drying reed beds : a case study on pilot-scale beds
2008
Troesch, S. | Liénard, A. | Molle, Pascal | Merlin, Gerard | Esser, D.
French legislation requires, the control of private on-site sanitation systems by local authorities. This will result in a large increase of the quantity of sludge from septic tanks to be treated. Nevertheless, large wastewater treatment plants are not systematically able to treat this sludge because they may have reached their nominal load or they are not so numerous in rural zone to avoid too long transportation. The study concerns both, the feasibility of sludge reed beds devoted to the treatment of septage and the assessment of a simultaneous treatment with aerated sludge. The experiments have been carried out on eight pilot-scale drying reed beds (2m²) planted with Phragmites australis. Two filtration layers of either vegetal compost or sand were tested. The study is focused on the commissioning period (first vegetative year) with a loading rate of 30 kgSS.m-2.yr-1. According to these operational conditions, dewatering efficiencies reached approx. 30% DM during summer but less than 20%DM in winter for each filtration layer and sludge. High removal efficiencies, with an average of 96%, 92% and 89% for SS, COD and TKN respectively, were achieved with septage whereas they were lower for the mixture of aerated sludge and septage. The dewaterability of septage and its filtration behaviour were assessed by several parameters (Capillary Suction Time, bound water) which may be some interesting tools for an optimised loading strategy.
Afficher plus [+] Moins [-]Sludge drying reed beds : a full and pilot-scales study for activated sludge treatment
2008
Troesch, S. | Liénard, A. | Molle, Pascal | Merlin, Gerard | Esser, D.
Sludge drying reed beds have been used for dewatering and mineralization of sludge since the beginning of the 90's, but their insufficient performances in terms of Dry Matter [DM] content and mineralization of the sludge have made necessary new studies. Therefore, 8 pilots of 2m² each and a full-scale plant (13 000 p.e , 8 beds of 470m² in operation for 4 years) have been monitored to examine the influence of the sludge loading rate, the sludge quality and the loading frequency on the dewatering and mineralization efficiencies. Two filtration layers and two loading rhythms were tested on pilots which were fed at a loading rate of 25-30 kgDM.m-2.yr-1 during the first year of operation (commissioning period). Hydraulic behaviour (infiltration rate, outflow), O2 and CO2 relative concentrations in the filtration media, redox potential, pollutants removal and dry matter content were assessed during all the study. The rheological quality of the extracted sludge from full scale beds was assessed and showed that its mechanical behaviour exceed those of sludge of comparable dry matter content, making its spreading easier. Therefore, these sludge could easily claim the status of solid and stabilized sludge according to the French regulation. Design and management recommendations (number of beds, loading rates, feeding/rest period) gained from the experiments results are suggested.
Afficher plus [+] Moins [-]Heavy metals and trace elements content in camel milk and shubat from Kazakhstan
2008
Meldebekova, Aliya | Konuspayeva, Gaukhar | Diacono, Emilie | Faye, Bernard
In Kazakhstan, camel milk is mainly consumed after fermentation process. The fermented camel milk, named shubat, is generally home-made by the traditional process. The changes in mineral composition of camel milk during the fermentation process were rarely studied especially for heavy metals. The present study aimed to assess the change in heavy metals and trace-elements contents during the fermentation process. Samples of milk and shubat were collected in eight farms of Southern Kazakhstan in order to determine copper, iron, manganese, zinc, arsenic and lead. In camel milk mean content of these heavy metals was respectively of 0.065 ± 0.04, 1.478 ± 0.53, 0.084 ± 0.03, 5.163 ± 2.17, <0.1 and 0.025 ± 0.02 ppm. In shubat, the mean content was 0.163 ± 0.164, 1.57 ± 0.46, 0.088 ± 0.02, 7.217 ± 2.55, and 0.007 ppm respectively. Arsenic was detected in some samples of milk and shubat only. A relationship between heavy metals in raw milk and shubat at the farm level was observed. (Résumé d'auteur)
Afficher plus [+] Moins [-]Hydrotelluric and industrial fluorosis survey in the dromedary camel in the south of Morocco
2008
Diacono, Emilie | Faye, Bernard | Bengoumi, Mohammed | Kessabi, Mohamed
Morocco is the first country producer of phosphate in the world with a real potential of contamination of the environment and individuals there living by fluorine either by phosphate deposits (hydrotelluric fluorosis) and phosphate manufacturing plants (industrial fluorosis). This survey was achieved on 86 dromedaries in a region of the Sahara (Boujdour and Laâyoune) characterized by the presence of phosphate. In addition, blood, soil, water and plant samples were collected for the dosage of fluorine that has been achieved by potentiometric method. The mean fluorine content was below 0.47 ppm, 513 ppm and 4.8 ppm in water, soil and plants respectively. The provinces of Boujdour and Laâyoune are unscathed zones opposite the sources of fluorine contamination, as water, vegetation and soil. The mean plasma fluorine concentration was below 0.06 ppm, thus, the camels of these regions seem therefore also free of fluorine chronic intoxication. However the increased values of fluorine levels in the soil, vegetables, and the plasma of camels in the region of Boujdour can let suppose that this area is close to a source of fluorine contamination. Indeed, the province of Boujdour is located unless 200 km of Boukraa where is situated a processing plant of phosphates. Thus, according orientation and the strength of the present dominant winds in the region of Boujdour, we can give out the hypothesis that by winds are brought in the region of Boujdour of the fluorine particles coming from the region of Boukraa. These winds carrying particles of fluorine eliminated by the factory and also by the extraction of soil particles by erosion. This hypothesis can be verified by a survey establishing a gradient of pollution by fluorine cleared by the deposit or the processing plant of the phosphates considering the direction and the strength of the dominant winds in these regions. (Résumé d'auteur)
Afficher plus [+] Moins [-]Trace elements and heavy metals statuts in Arabian camel
2008
Faye, Bernard | Seboussi, Rabiha | Askar, Mustapha
In the desert, camel rearing is an important cultural fact. In the present paper, 240 Arabian camels from Emirates were sampled for the determination of trace elements and different heavy metals. The following elements were tested: copper, zinc, iron, aluminium, arsenic, boron, barium, cobalt, chromium, cadmium, manganese, molybdenum, nickel, selenium, strontium and lead. The variation factors included age, sex and physiological status. On the average, the mineral contents were 190.3 µg/100 ml (iron), 60.1 µg/100 ml (copper), 44.0 µg/100 ml (strontium), 22.5 µg/100 ml (arsenic), 20.0 µg/100 ml (zinc), 19.7 µg/100 ml (selenium), 19.3 µg/100 ml (boron) and 14.6 µg/100 ml (barium). Other minerals like aluminium (3.7 µg/100 ml), molybdenum (2.9 µg/100 ml), chromium (2.0 µg/100 ml), nickel (1.8 µg/100 ml), lead (1.5 µg/100 ml), manganese (0.16 µg/100 ml), cobalt (0.08 µg/100 ml) and cadmium (0.07 µg/100 ml) were in very small concentration. Age, sex and physiological effects were assessed for some parameters. According to the lack of references in camel species, it is difficult to link those results to polluting context. But those data could contribute to understand the heavy metal status in camel confronted to pollution. (Résumé d'auteur)
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