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Sediment pollution: An assessment of anthropogenic and geogenic trace element contributions along the central Algerian coast
2023
Aroua, Mohamed | Boulahdid, Mostefa | Radakovitch, Olivier | Benhalima, Moustafa | Guendouzi, Yassine | Fowler, Scott | Ambrosi, Jean-Paul | Ecole Nationale Supérieure des Sciences de la Mer et de l'Aménagement du Littoral (ESSMAL) | Laboratoire de recherche sur les transferts des radionucléides dans les écosystèmes aquatiques (IRSN/PSE-ENV/SRTE/LRTA) ; Service de recherche sur les transferts et les effets des radionucléides sur les écosystèmes (IRSN/PSE-ENV/SRTE) ; Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN) | Stony Brook University [SUNY] (SBU) ; State University of New York (SUNY) | Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE) ; Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | This research work was financiallysupported by the French program METMAR-MERMEX as part of the PHCTASSILI project (Code PHC: 17MDU986; Title: Inputs, accumulationsand trace metal contamination in Algiers and Marseille coastal areas).
International audience | Sediment cores from the central Algerian coast were collected to investigate the distribution, sources and risk oftrace metals. The local geochemical background of metals was defined from the core S collected in an uncontaminatedarea of the coast. The anthropogenic inputs in Algiers Bay elevated Ag, Cd, Pb and Zn concentrationsas their maximum were 3.1, 3, 2.1 and 1.8 times the background values, respectively. Meanwhile, increasedcontents of Arsenic (up to 21.1 mg/kg) were detected in all sites. Correlations and PCA suggest that lithogenicsources controlled metal deposition, while most sediment arsenic was agriculture-derived. Organic matter actedas a sink or source for some trace metals. According to EFs, the study area showed slight to moderate enrichmentwith respect to Ag, As, Pb, Cd, Zn and Cu, whereas they remained uncontaminated with Cr, V, Co and Ni. Thisstudy provides a needed baseline for future environmental investigations.
Mostrar más [+] Menos [-]Potential of fluorescent tracers to appraise biochar amendment strategies for pesticide mitigation — insights from comparative sorption
2023
Sene, Seynabou | Dollinger, Jeanne | Hammecker, Claude | Lagacherie, Manon | Negro, Sandrine | Samouëlian, Anatja | Laboratoire d'étude des Interactions Sol - Agrosystème - Hydrosystème (UMR LISAH) ; Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Montpellier ; Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro) | The study was funded by the Carbonex Company in the framework of a research and development project.
Mitigation of pesticide dispersion in soil and water is required to protect ecosystem health and the anthropic uses of water bodies. Biochar amendments have been suggested to reduce pesticide dispersion due to their high sorption potentials. Nevertheless, appraisals at different scales have been limited by the costs of pesticide analyses. The aim of this study was to evaluate the potential of two fluorescent tracers, uranine (UR) and sulforhodamine B (SRB), for use as pesticide proxies in the context of biochar amendments used for mitigation purposes. Therefore, we compared the sorption processes of both fluorescent tracers and those of three pesticides, glyphosate, 2,4-D, and difenoconazole for soils; three wood biochars (pine, oak, and beech/charm blend); and soil/biochar mixtures representing agricultural usages. The results showed that the sorption of glyphosate by soil was unaffected by amendment with the tested pine, oak, and wood blend biochars. In contrast, the sorption coefficients of UR, SRB, 2,4-D, and difenoconazole were significantly increased with these biochar amendments. SRB, in particular, exhibited sorption behavior similar to that of the hydrophobic fungicide difenoconazole. This indicates promise for the use of SRB as a proxy for hydrophobic pesticides, in testing biochar amendments.
Mostrar más [+] Menos [-]Assessment of contaminants in blue sharks from the Northeast Atlantic: Profiles, accumulation dynamics, and risks for human consumers
2023
Alves, Luís M.F. | Lemos, Marco F.L. | Moutinho, Ariana, B | Ceia, Filipe, R | Muñoz-Arnanz, Juan | Jiménez, Begoña | Cabral, Henrique | Novais, Sara, C | Marine and Environmental Sciences Centre [Portugal] (MARE) ; Instituto Universitário de Ciências Psicológicas, Sociais e da Vida = University Institute of Psychological, Social and Life Sciences (ISPA) | institute of organic chemistry (IQOG-GSIC), Madrid, Spain (IQOC-CSIC) | Ecosystèmes aquatiques et changements globaux (UR EABX) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
International audience | Chemical pollution is a major threat to marine ecosystems, and top predators such as most shark species are extremely vulnerable to being exposed and accumulating contaminants such as metals and persistent organic pollutants (POPs). This work aimed to study the degree, composition, and the sources of contamination in the blue shark (Prionace glauca) inhabiting the Northeast Atlantic, as well as the potential risk faced by human consumers. A total of 60 sharks were sampled in situ aboard fishing vessels, and the concentrations of a set of metals and POPs were analysed in various tissues and complemented with stable isotope analyses. High levels of contaminants were found in most sharks sampled. The concentrations of most metals were higher in the muscle when compared with the liver. Regarding the dangers to consumers posed by the concentrations of arsenic (As), mercury (Hg), and lead (Pb), over 75% of the sharks presented muscle concentrations of at least one contaminant above the legal limits for human consumption, and a risk assessment determined that consumption of meat of these sharks exceeding 0.07 Kg per week could potentially expose human consumers to dangerous amounts of methylmercury (MeHg). Additionally, the assessment of single contaminants may lead to an underestimation of the risk for the human health. Finally, the overall accumulation of contaminants seems to be mostly influenced by the sharks' geographical distribution, rather than sex, size, or trophic level of their prey. ☆ This paper has been recommended for acceptance by Christian Sonne.
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