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Reliability-based design and implementation of crow search algorithm for longitudinal dispersion coefficient estimation in rivers
2021
Ghaemi, Alireza | Zhian, Tahmineh | Pirzadeh, Bahareh | Hashemi Monfared, Seyedarman | Mosavi, Amir
publishedVersion
Show more [+] Less [-]Per-and polyfluoroalkyl substances (PFASs) in Contaminated Coastal Marine Waters of the Saudi Arabian Red Sea: A baseline study
2020
Ali, Aasim Musa Mohamed | Higgins, Christopher | Alarif, Walied | Al-Lihaibi, Sultan | Ghandourah, Mohammed | Kallenborn, Roland
publishedVersion | Per- and polyfluoroalkyl substances (PFASs) are today considered important constituents of the continuously growing substance group of persistent contaminants of emerging environmental concern (PCEC). Here, we report for the first time the concentrations of 12 relevant PFASs in 28 marine water samples from the Saudi Arabian coastal waters of the Red Sea. The sum levels of 12 PFASs (Σ12 PFAS) in surface seawater ranged from <LOQ to 956 ngL−1. For the reference background site of this study, Σ12 PFAS levels ranged from <LOQ to 10.9 ng/L. The highest PFAS levels have been found in Al-Arbaeen and Al-Shabab, two lagoons continuously receiving treated sewage effluents. PFHxA, PFHxS, and 6:2 FTS were the most prevalent PFASs with relatively high concentrations. Discharge of municipal and industrial wastewaters is considered an important source of PFASs. The pattern of PFASs observed here suggests that the usage of PFAS-containing aqueous film-forming foams (AFFFs) is a potential additional source for these compounds in Al-Arbaeen and Al-Shabab lagoons. However, a systematic elucidation of local PFASs sources is needed. Contamination of the Red Sea waters with PFASs poses a potential imminent risk to the marine environment of the Red Sea and ultimately may even affect the health of human consumers through the consumption of local seafood
Show more [+] Less [-]Biomarker and hematological fieldwork with amphibians: is it necessary to sample all night?
2020
Brodeur, Celine Marie | Bahl, María Florencia | Natale, Guillermo Sebastian | Poliserpi, Maria Belen
In the context of the global amphibian crisis, biomonitoring constitutes a valuable assessment tool to provide critical up to date information on the status and health of amphibians worldwide. The aim of the current study was to evaluate the possible confounding effects of sex, size, and time since capture on enzymatic biomarkers and hematologic parameters of the South American frog Leptodactylus latrans. Frogs were collected by hand between 9 pm and 12 am on two consecutive nights. On the first night, captured frogs were transported for 2 h by car to laboratory installations, maintained overnight in plastic containers, and blood and tissue sampled on the next morning. In contrast, frogs collected on the second night were blood and tissue sampled in the field, immediately after the capture period. Hematological parameters were analyzed, and enzymatic activities of catalase, cholinesterase (ChE), and glutathione S-transferase (GST) were determined in the plasma, liver, kidney, and muscle. A sex difference was observed only for total white blood cell counts (WBC), females exhibiting significantly greater values than males. The packed cell volume (PCV), mean corpuscular hemoglobin concentration (MCHC), WBC, and muscle ChE activity were significantly correlated with snout-vent length (SVL). The correlation was inversed in the case of MCHC, WBC, and muscle ChE, while the correlation was positive between PCV and SVL. Most examined parameters presented similar values when frogs were sampled at night following capture or the next morning. Total red blood cells (RBCs) count, and plasma enzymatic activities of ChE and GST were the only parameters that presented significantly increased values in morning samplings compared with night samplings. Overall, the current study indicates that it is best to sample the frogs as soon as possible after capture if hematologic or plasmatic biomarkers are examined. Nevertheless, it is possible to sample on the next morning if tissular biomarkers are employed. | Instituto de Recursos Biológicos | Fil: Brodeur, Celine Marie Julie. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Recursos Bilológicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. | Fil: Bahl, María Florencia. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Química. Centro de Investigaciones del Medio Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. | Fil: Natale, Guillermo S. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Química. Centro de Investigaciones del Medio Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. | Fil: Poliserpi, María Belen. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Recursos Biológicos; Argentina
Show more [+] Less [-]Lethal and sublethal effects of the natural and healthy spinosad-based formulation Tracer™ on tadpoles of two neotropical species
2020
Bahl, María Florencia | Brodeur, Celine Marie | Salgado Costa, Carolina | D'andrea, María Florencia | Sansiñena, Jesica Alejandra | Marino, Damian Jose Gabriel | Natale, Guillermo Sebastián
This paper presents the first acute toxicity data of the natural insecticide spinosad in amphibians. The sensitivity of two neotropical sympatric anuran species, Boana pulchella and Rhinella arenarum, to spinosad-based formulation Tracer™ was evaluated. Lethal effects are reported in tadpoles of B. pulchella stage 25 between 2.81 and 35.44 mg spinosad/L, while for the same concentration range no lethal effects were detected in tadpoles of R. arenarum of the same stage. In addition, Tracer™ produced sublethal effects at the individual level on the swimming activity, morphology (growth and presence of abnormalities), and development of B. pulchella from 2.81 to 5.78 mg spinosad/L, while in R. arenarum effects were only detected in the swimming activity and growth from 2.78 and 6.22 mg/L, respectively. At the biochemical level, Tracer™ produced inhibition of different enzymatic activities, among them, catalase activity at 2.81 mg spinosad/L, glutathione S- transferase activity from 2.81 to 2.98 mg spinosad/L, and acetylcholinesterase activity at 2.81 mg spinosad/L. These findings allow us to conclude that B. pulchella is more sensitive than R. arenarum to spinosad-based formulation Tracer™. The effects demonstrated here are not consistent with those expected since spinosad is supposed to be an environmental healthy alternative. This paper provides useful and necessary information to implement regulations on the use of new compounds entering the market and its associated risks. | Instituto de Recursos Biológicos | Fil: Bahl, María Florencia. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Química. Centro de Investigaciones del Medio Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. | Fil: Brodeur, Celine Marie Julie. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Recursos Bilológicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. | Fil: Salgado Costa, Carolina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Química. Centro de Investigaciones del Medio Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. | Fil: D'Andrea, María Florencia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Recursos Bilológicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. | Fil: Sansiñena, Jesica Alejandra. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Química. Centro de Investigaciones del Medio Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. | Fil: Marino, Damián José. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Química. Centro de Investigaciones del Medio Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. | Fil: Natale, Guillermo S. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Química. Centro de Investigaciones del Medio Ambiente; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.
Show more [+] Less [-]Retour d'expérience des filtres d'apatite granulée en taille réelle pour la rétention du phosphore dans les filtres plantés de roseaux | Full scale experience of granulated apatite filters for phosphorous retention in treatment wetlands.
2018
Delgado Gonzalez, L. | Gerbier, C. | Prost Boucle, S. | Troesch, S. | Molle, Pascal
There are 20 full-scale Phosclean® filters for P removal being used together with treatment wetlands (TW) to treat wastewaters of small and medium-size communities, in France. Some of them are in operation for more than five years now, reason why some field experiences are being conducted under the project name of APPROVE (APatite for P Removal and Valorisation: an Evaluation) to assess the current performance and saturation conditions of full-scale filters. This paper will present fieldfeedback results from 4 different wastewater treatment plants (WWTP) with Phosclean® filters. WWTP A (filter A) has been monitored since its commission in 2017 to assess the effluent's pH evolution due to material dissolution in the very first stage of its life span. Three other WWTPs (B, C and D) with hydraulically different Phosclean® filters, in operation since 2012, are also monitored: vertical up-flow (filter B); vertical down-flow (filter C) and horizontal flow (filter D). Assessment of the treatment plants use regulatory surveys since the beginning of plants operations. As treatment plants have not the same capacity, the number of regulatory surveys is heterogeneous and not high enough to have a precise knowledge on saturation levels and retention kinetics. Consequently, additional measurement campaigns have been carried out over two years. Four-day campaigns have been carried out twice per year for each WWTP. In order to evaluate the P retention's performance, 24h-flow proportional samplings at the inlet and outlet of the Phosclean® filter were coupled to spotsamplings at different hydraulic retention times inside the filter to measure retention's kinetic. Online P-PO4 measurements at the outlet of the filter were also conducted to observe possible dynamic within a day. Mayor parameters as pH, conductivity, redox potential, TSS, BOD, COD, N, TP, P-PO4 3- as well as anions and cations were measured for these samples. For filter A, a flowmeter and an online pH probe at the outlet of the filter have been implemented for several months. To determine the nature of phosphate precipitates, SEM and DRX analyses were performed for solid samples taken at different points in the filters. Furthermore, fluorescein-tracer tests were carried out to precisely determine water retention times and possible short-circuiting, as well as dynamic penetrometer measurements to assess potential changes on the material density due to surface precipitation. Results of first campaigns show that P concentration at the outlet of filters C and D respect the maximal regulation limit for total phosphorous disposal after 5 years of operation. This is not the case for filter B, after 4 years of operation, which is over the regulation limit fixed at 2.5mgTP/L. Nevertheless, differences in the regulation limits, inlet P concentrations, hydraulic loads, operation and design, must be taken into consideration to analyze variations of filters performances. The evolution of TP concentrations along time will be presented for all filters according to saturation levels for comparison. Kinetics evolution as a function of saturation conditions will be also presented. Results show that filters B, C and D are at different saturation levels, being filter B the most saturated.
Show more [+] Less [-]Pore scale monitoring of the resting period and oxygenation of filtering media in Vertical Flow Treatment Wetland by X-ray tomography | Suivi de la période de repos de la couche filtrante des filtres plantés de roseaux par tomographie RX
2018
Martinez Carvajal, G. | Oxarango, L. | Molle, Pascal | Forquet, N.
This study aims to enlighten the geometric changes at the pore scale of filtering media of Vertical Flow Treatment Wetlands (VFTW) and their influence on oxygenation during the rest period. A 3-day ex-situ drying of six samples of a VFTW was carried out at controlled temperature, and relative humidity simulating the rest period. Samples (16-cm long) were taken at the end of the feeding period of a filter in the first stage and let dry. Three of the samples were sterilized before drying using gamma rays to differentiate oxygenation without bacterial activity. At 0, 1 and 3 days of drying, X-ray scans of the samples were performed to observe changes in the samples structure. After each scan, the oxygen transport within the sample was studied by measuring vertical oxygen concentration profiles. Although X-ray tomography allows small structure changes to be detected, it is necessary to modify the drying conditions perform a more realistic drying. The complexity of the results of oxygen profiles lead us to suggest the use of CFD tools to understand how oxygenation occurs.
Show more [+] Less [-]La mesure des polluants…vers la démesure ?
2016
Camel, Valérie
La mesure des polluants…vers la démesure ?. Pollution chimique : la santé en jeu
Show more [+] Less [-]L’agriculture entre pollution atmospherique et changement climatique
2016
Cellier, Pierre | Génermont, Sophie,
Les agroécosystèmes sont des sources et des puits de polluants atmosphériques et de gaz à effet de serre et, par là-même, ils interviennent dans les relations entre climat et pollution de l’air. Cette contribution, positive ou négative, résulte de processus complexes, à la fois directs et indirects, et prend des formes très diverses : augmentation ou diminution des émissions et dépôts, augmentation attendue de la fréquence des feux, modification de la protection phytosanitaire etc. Comme pour la plupart des processus biologiques, les incertitudes sont importantes et les verrous de connaissances restent nombreux, alors qu’une connaissance des différents facteurs d’influence, naturels et anthropiques est nécessaire pour limiter la contribution des agroécosystèmes à la fois au changement climatique et à la pollution de l’air, tout en préservant les performances économiques de l’activité agricole. Enfin, l’agriculture est concernée par tout un ensemble de politiques publiques relatives au changement climatique et à la pollution de l’air, mais également à la pollution des eaux et à la protection de l’environnement, politiques publiques qui peuvent interagir en synergie ou être antagonistes. | Interactions between climate change and air pollution in the context of agriculture. Agroecosystems are sources and sinks of atmospheric pollutants and greenhouse gases. They are therefore involved in climate change and air pollution and their cross-relations. This contribution can be positive or negative. It results from complex processes, both direct and indirect, which is related to a range of topics: increase or decrease of emission and deposition, increase in fire frequency, change in plant protection etc. As for most of biological processes, there are large uncertainties and knowledge is lacking over a range of fields. However it is necessary to have a global overview of the involved processes and drivers when trying to limit the contribution of agroecosystem both to climate change and air pollution, with attention to the economic sustainability of agriculture under global change. Moreover agriculture activities refer to public policies related not only to climate change and air pollution but also water pollution or protection of the environment. These policies may interact positively or be antagonist.
Show more [+] Less [-]Contribution de la combustion de biomasse sur les niveaux de PM10 dans la Vallée de l’Arve
2014
Chevrier, F. | Močnik, G. | Brulfert, G. | Laurent, J.-P. | Jaffrezo, J.-L. | Besombes, Jean-Luc
Metallothioneins pattern during ontogeny of coastal dolphin, Pontoporia blainvillei, from Argentina
2014
Polizzi, P.S. | Romero, M.B. | Chiodi Boudet, L.N. | Das, Krishna | Denuncio, P.E. | Rodriguez, D.H. | Gerpe, M.S.
peer reviewed | Metallothioneins are signals of metal exposure and widely used in biomonitoring. Franciscana dolphin is an endemic cetacean from the Southwestern Atlantic Ocean, classified as Vulnerable A3d by the IUCN. Metallothionein, copper and zinc in Franciscana were assessed in two geographic groups; one inhabits La Plata River estuary, anthropogenically impacted, and the other inhabits marine coastal ecosystems, with negligible pollution. Despite the environment, hepatic and renal MT concentrations were similar, but there was a declining trend from early to later developmental stages. Metallothionein K/L, Cu and Zn levels corresponded to normal reported ranges. MT was not related with Cd. Fetal concentrations were higher than its mother. These results and the health status of dolphins are suggesting that MT correspond to physiological ranges for the species, and they are closely to homeostasis of Zn and Cu, according to its ontogenetic changes. The information constitutes the first MT information on Franciscana dolphin and can be considered as baseline for the species conservation.
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