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Cadmium distribution in mature durum wheat grains using dissection, laser ablation-ICP-MS and synchrotron techniques *
2020
Yan, Bofang | Isaure, Marie-Pierre | Mounicou, Sandra | Castillo-Michel, Hiram | De Nolf, Wout | Nguyen, Christophe | Cornu, Jean-Yves
Understanding how essential and toxic elements are distributed in cereal grains is a key to improving the nutritional quality of cereal-based products. The main objective of this work was to characterize the distribution of Cd and of nutrients (notably Cu, Fe, Mn, P, S and Zn) in the durum wheat grain. Laser ablation inductively coupled mass spectrometry and synchrotron micro X-ray fluorescence were used for micro-scale mapping of Cd and nutrients. A dissection approach was used to quantitatively assess the distribution of Cd and nutrients among grain tissues. Micro X-ray absorption near-edge spectroscopy was used to identify the Cd chemical environment in the crease. Cadmium distribution was characterized by strong accumulation in the crease and by non-negligible dissemination in the endosperm. Inside the crease, Cd accumulated most in the pigment strand where it was mainly associated with sulfur ligands. High-resolution maps highlighted very specific accumulation areas of some nutrients in the germ, for instance Mo in the root cortex primordia and Cu in the scutellum. Cadmium loading into the grain appears to be highly restricted. In the grain, Cd co-localized with several nutrients, notably Mn and Zn, which challenges the idea of selectively removing Cd-enriched fractions by dedicated milling process.
Mostrar más [+] Menos [-]Physico-chemical and agronomic results of soil remediation by In Situ Chemical Reduction applied to a chlordecone-contaminated nitisol at plot scale in a French Caribbean banana plantation
2020
Mouvet, Christophe | Collet, Bastien | Gaude, Jean-Marie | Rangon, Luc | Bristeau, Sébastien | Senergues, Mathilde | Lesueur-Jannoyer, Magalie | Jestin, Alexandra | Hellal, Jennifer | Woignier, Thierry
The In Situ Chemical Reduction (ISCR) process was tested in a nitisol in a French Caribbean banana plantation using five different soil amendments. The addition of 2.8% or 4.0% of Zero Valent Iron (ZVI; dw/dw, 2 different trial plots) in the 0–40-cm soil layer lowered the initial chlordecone (CLD) concentration by up to 74% or 69% in 37 days or 94 days, with 75% of the decrease achieved after only 21 or 24 days of treatment depending on the trial plot. The addition of commercially available Daramend® was also tested by applying the 6% dose (dw/dw) recommended by the manufacturer and using either the regular alfalfa-based product or a bagasse-based product specifically formulated for the study. Both significantly lowered CLD concentrations, but to a lesser extent than with the ZVI-only amendment. A bagasse-ZVI mixture prepared on site produced results slightly better than the two Daramend®. The percentage decreases in CLD concentrations were correlated with the negative redox potentials achieved. In all the trial plots, dechlorinated transformation products appeared in the soil and soil water as the CLD concentrations decreased, with H atoms replacing up to 4 and 7 of the 10 Cl atoms, respectively. None of these degradation products appeared to accumulate in the soil or soil water during the treatment. Instead, the reverse occurred, with an overall downward trend in their concentrations over time. The effects of ISCR treatment on agronomic and human health–related parameters were measured in three different crops. The radishes produced with some treatments were visually of lower quality or smaller in size than those grown in the control plots. Lower yields were observed for the cucumbers and sweet potatoes grown after applying the bagasse-based amendments. Mortality among cucumber seedlings was observed after treatment with ZVI only. Simple operational solutions should suffice to remedy these negative agronomic effects. As regards human health–related effects, the CLD concentrations in radishes grown with three of the amendments were significantly lower than in the two control plots and well below the maximum residue level (MRL), which was substantially exceeded in the radishes grown on untreated soil. For cucumbers, the treatments with regular Daramend® and with a local bagasse-ZVI mixture produced fruits with CLD below the MRL and also below the concentrations in one of the two control plots. As for the sweet potatoes, adding a bagasse-ZVI mixture had a significant positive effect by decreasing contamination below the levels in the two control plots and below the MRL.
Mostrar más [+] Menos [-]Analysis of surface water reveals land pesticide contamination: An application for the determination of chlordecone-polluted areas in Guadeloupe, French West Indies
2020
Rochette, Romain | Bonnal, Vincent | Andrieux, Patrick | Cattan, Philippe
In Guadeloupe, the use between 1972 and 1993 of chlordecone, an organochlorine insecticide, has permanently contaminated the island's soil, thus contaminating the food chain at its very beginning. There is today a strong societal requirement for an improved mapping of the contaminated zones. Given the extent of the areas to be covered, carrying out soil tests on each plot of the territory would be a long and expensive process. In this article, we explore a method of demarcating polluted areas. The approach adopted consists in carrying out, using surface water analyses, a hydrological delimitation that makes it possible to distinguish contaminated watersheds from uncontaminated ones. The selection of sampling points was based on the spatial analysis of the actual and potential contamination data existing at the beginning of the study. The approach was validated by soil analyses, after having compared the contamination data of the watersheds with the soil contamination data of the plots within them. The study thus made it possible to highlight new contaminated areas and also those at risk of contamination and to identify the plots to be targeted as a priority during future analysis campaigns by State services.
Mostrar más [+] Menos [-]Physical limitation of pesticides (chlordecone) decontamination in volcanic soils: Fractal approach and numerical simulation
2020
Woignier, Thierry | Rangon, Luc | Clostre, Florence | Mottes, Charles | Cattan, Philippe | Primera, Philippe | Jannoyer, Magalie
In the French West Indies, the chlordecone (organochloride pesticide) pollution is now diffuse becoming new contamination source for crops and environment (water, trophic chain). Decontamination by bioremediation and chemical degradation are still under development but the physical limitations of these approaches are generally not taken into account. These physical limitations are related to the poor physical accessibility to the pesticides in soils because of the peculiar structural properties of the contaminated clays (pore volume, transport properties, permeability, and diffusion). Some volcanic soils (andosols), which represent the half of the contaminated soils in Martinique, contain nanoclay (allophane) with a unique structure and porous properties. Andosols are characterized by pore size distribution in the mesoporous range, a high specific surface area, a large pore volume, and a fractal structure. Our hypothesis is that the clay microstructure characteristics are crucial physico-chemical factors strongly limiting the remediation of the pesticide. Our results show that allophane microstructure (small pore size, hierarchical microstructure, and tortuosity) favors accumulation of chlordecone, in andosols. Moreover, the clay microporosity limits the accessibility of microorganisms and chemical species able to decontaminate because of poor transport properties (permeability and diffusion). We model the transport properties by two approaches: (1) we use a numerical model to simulate the structure of allophane aggregates. The algorithm is based on a cluster–cluster aggregation model. From the simulated data, we derived the pore volume, specific surface area, tortuosity, permeability, and diffusion. We show that transport properties strongly decrease because of the presence of allophane. (2) The fractal approach. We characterize the fractal features (size of the fractal aggregate, fractal dimension, tortuosity inside allophane aggregates) and we calculate that transport properties decrease of several order ranges inside the clay aggregates. These poor transport properties are important parameters to explain the poor accessibility to pollutants in volcanic soils and should be taken into account by future decontamination process. We conclude that for andosols, this inaccessibility could render inefficient some of the methods proposed in the literature.
Mostrar más [+] Menos [-]Spatio-temporal variability of water pollution by chlordecone at the watershed scale: what insights for the management of polluted territories?
2020
Mottes, Charles | Deffontaines, Landry | Charlier, Jean-Baptiste | Comte, Irina | Della Rossa, Pauline | Lesueur Jannoyer, Magalie | Woignier, Thierry | Adele, Georges | Tailame, Anne-Lise | Arnaud, Luc | Plet, Joanne | Rangon, Luc | Bricquet, Jean-Pierre | Cattan, Philippe
Chlordecone, applied on soils until 1993 to control banana weevil, has polluted water resources in the French West Indies for more than 40 years. At the watershed scale, chlordecone applications were not homogenous, generating a spatial heterogeneity of the pollution. The roles of climate, hydrology, soil, agronomy, and geology on watershed functioning generate a temporal heterogeneity of the pollution. This study questions the interactions between practices and the environment that induce such variability. We analyzed hydrological and water pollution datasets from a 2-year monitoring program on the Galion watershed in Martinique (French West Indies). We conjointly analyzed (i) weekly chlordecone (CLD) concentration monitored on 3 river sampling sites, (ii) aquifer piezometric dynamics and pollutions, and (iii) agricultural practices on polluted soils. Our results showed that chlordecone pollution in surface waters are characterized by annual trends and infra-annual variations. Aquifers showed CLD concentration 10 times higher than surface water, with CLD concentration peaks during recharge events. We showed strong interactions between rainfall events and practices on CLD pollution requiring a systemic management approach, in particular during post-cyclonic periods. Small sub-watershed with high CLD pollution appeared to be a substantial contributor to CLD mass transfers to the marine environment via rivers and should therefore receive priority management. We suggest increasing stable organic matter return to soil as well as external input of organic matter to reduce CLD transfers to water. We identified hydrological conditions—notably drying periods—and tillage as the most influential factors on CLD leaching. In particular, tillage acts on 3 processes that increases CLD leaching: organic matter degradation, modification of water paths in soil, and allophane clay degradation.
Mostrar más [+] Menos [-]Modelling bioaccumulation of heavy metals in soil-crop ecosystems and identifying its controlling factors using machine learning
2020
Hu, Bifeng | Xue, Jie | Zhou, Yin | Shao, Shuai | Fu, Zhiyi | Li, Yan | Chen, Songchao | Qi, Lin | Shi, Zhou | Unité de Science du Sol (Orléans) (URSols) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences ; Zhejiang University [Hangzhou, China] | Institute of Land Science and Property, School of Public Affairs ; Zhejiang University [Hangzhou, China] | School of Earth Sciences [Hangzhou] ; Zhejiang University [Hangzhou, China] | InfoSol (InfoSol) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Ningbo Planting Management Station ; Ningbo University (NBU)
The prediction and identification of the factors controlling heavy metal transfer in soil-crop ecosystems are of critical importance. In this study, random forest (RF), gradient boosted machine (GBM), and generalised linear (GLM) models were compared after being used to model and identify prior factors that affect the transfer of heavy metals (HMs) in soil-crop systems in the Yangtze River Delta, China, based on 13 covariates with 1822 pairs of soil-crop samples. The mean bioaccumulation factors (BAFs) for all crops followed the order Cd > Zn > As > Cu > Ni > Hg > Cr > Pb. The RF model showed the best prediction ability for the BAFs of HMs in soil-crop ecosystems, followed by GBM and GLM. The R2 values of the RF models for the BAFs of Zn, Cu, Cr, Ni, Hg, Cd, As, and Pb were 0.84, 0.66, 0.59, 0.58, 0.58, 0.51, 0.30, and 0.17, respectively. The primary controlling factor in soil-to-crop transfer of all HMs under study was plant type, followed by soil heavy metal content and soil organic materials. The model used herein could be used to assist the prediction of heavy metal contents in crops based on heavy metal contents in soil and other covariates, and can significantly reduce the cost, labour, and time requirements involved with laboratory analysis. It can also be used to quantify the importance of variables and identify potential control factors in heavy metal bioaccumulation in soil-crop ecosystems.
Mostrar más [+] Menos [-]Current status, spatial features, health risks, and potential driving factors of soil heavy metal pollution in China at province level
2020
Hu, Bifeng | Shao, Shuai | Ni, Hao | Fu, Zhiyi | Hu, Linshu | Zhou, Yin | Min, Xiaoxiao | She, Shufeng | Chen, Songchao | Huang, Mingxiang | Zhou, Lianqing | Li, Yan | Shi, Zhou | Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences ; Zhejiang University [Hangzhou, China] | Unité de Science du Sol (Orléans) (URSols) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Université d'Orléans (UO) | Department of Earth System Science [Tsinghua] ; Tsinghua University [Beijing] (THU) | School of Earth Sciences, Zhejiang University (ZJU) | College of Environmental and Resource Sciences, Zhejiang University | Institute of Land Science and Property, School of Public Affairs ; Zhejiang University [Hangzhou, China] | InfoSol (InfoSol) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Information Center of Ministry of Ecology and Environment | Institute of Agricultural Remote Sensing and Information Technology Application ; Zhejiang University [Hangzhou, China]
International audience | In this study we systematically reviewed 1203 research papers published between 2008 and 2018 in China and recorded related data on eight kinds of soil heavy metals (Cr, Pb, Cd, Hg, As, Cu, Zn, and Ni). Based on that, the pollution levels, ecological risk and health risk caused by soil heavy metals were evaluated and the pollution hot spots and potential driving factors of different heavy metals in different provinces were also identified. Results indicated accumulation of heavy metals in soils of most provinces in China compared with background values. Consistent with previous findings, the most prevalent polluted heavy metals were Cd and Hg. Polluted regions are mainly located in central, southern and southwestern China. Hunan, Guangxi, Yunnan, and Guangdong provinces were the most polluted provinces. For the potential health risk caused by heavy metals pollution, children are more likely confront with non-carcinogenic risk than adults and seniors. And children in Hunan and Guangxi province were experiencing relatively larger non-carcinogenic risk. In addition, children in part of provinces were undergoing potentially carcinogenic risks due to soil heavy metals exposure. Furthermore, in our study the 31 provinces in mainland China were divided into six subsets according to corresponding potential driving factors for heavy metal accumulation. Our study provide more comprehensive and updated information for contributing to better soil management, soil remediation, and soil contamination control in China.
Mostrar más [+] Menos [-]Surface modifications at the oxide/water interface: implications for Cu binding, solution chemistry and chemical stability of iron oxide nanoparticles
2020
Demangeat, Edwige | Pédrot, Mathieu | Dia, Aline | Bouhnik-Le Coz, Martine | Davranche, Mélanie | Cabello-Hurtado, Francisco | Géosciences Rennes (GR) ; Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR) ; Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS) | Université de Rennes (UR) | Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO) ; Université de Rennes (UR)-Institut Ecologie et Environnement (INEE) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR) ; Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS) | Centre National de la Recherche Scientifique INSU/INEE EC2CO | Inter-disciplinary Mission programs through the NanoOrgaTraces’ and ‘ALIEN’project | the University of Rennes “Défis Scientifiques Emergents”
International audience | The oxidation of magnetite into maghemite and its coating by natural organic constituents are common changes that affect the reactivity of iron oxide nanoparticles (IONP) in aqueous environments. Certain ubiquitous compounds such as humic acids (HA) and phosphatidylcholine (PC), displaying a high affinity for both copper (Cu) and IONP, could play a critical role in the interactions involved between both compounds. The adsorption of Cu onto four different IONP was studied: magnetite nanoparticles (magnNP), maghemite NP (maghNP), HA- and PC-coated magnetite NP (HA-magnNP and PC-magnNP, respectively). According to the results, the percentage of adsorbed Cu increases with increasing pH, irrespective of the IONP. Thus, protonation/deprotonation reactions are likely involved within Cu adsorption mechanism. Contrary to the other studied IONP, HA-magnNP favor Cu adsorption at most of the pH tested including acidic pH (pH = 3), suggesting that part of the active surface sites for Cu2+ were not grabbed by protons. The Freundlich adsorption isotherm of HA-magnNP provides the highest sorption constant KF (bonding energy) and n value which supports a heterogeneous sorption process. The heterogeneous adsorption between HA-magnNP and Cu2+ can be explained by both the diversity of the binding sites HA procured and the formation of multidendate complexes between Cu2+ and some of the HA functional groups. Such favorable adsorption process was neither observed on PC-coated-magnNP nor on maghNP, whose behaviors were comparable to that of magnNP. On another hand, HA and PC coatings considerably reduced iron (Fe) dissolution from magnNP as compared with magnNP. It was suggested that HA and PC coatings either provided efficient shield against Fe leaching or fostered dissolved Fe re-adsorption onto the functional groups at the coated magnNP surfaces. Thus, this study can help to better understand the complex interfacial reactions between cations-organic matter-colloidal surfaces which are relevant in environmental and agricultural contexts.This work showed that magnetite NP properties can be affected by surface modifications, which drive NP chemical stability and Cu adsorption, thereby affecting the global water chemistry.
Mostrar más [+] Menos [-]Associations between persistent organic pollutants and endometriosis: A multipollutant assessment using machine learning algorithms
2020
Matta, Komodo | Vigneau, Evelyne | Cariou, Véronique | Mouret, Delphine | Ploteau, Stéphane | Le Bizec, Bruno | Antignac, Jean-Philippe | Cano-Sancho, Germán | Laboratoire d'étude des Résidus et Contaminants dans les Aliments (LABERCA) ; École nationale vétérinaire, agroalimentaire et de l'alimentation Nantes-Atlantique (ONIRIS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Statistique, Sensométrie et Chimiométrie (StatSC) ; École nationale vétérinaire, agroalimentaire et de l'alimentation Nantes-Atlantique (ONIRIS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Centre hospitalier universitaire de Nantes (CHU Nantes)
International audience
Mostrar más [+] Menos [-]Early-life exposure to artificial light at night elevates physiological stress in free-living songbirds
2020
Grunst, Melissa | Raap, Thomas | Grunst, Andrea | Pinxten, Rianne | Parenteau, Charline | Angelier, Frédéric | Eens, Marcel | Department of Biology, Behavioural Ecology and Ecophysiology Group ; University of Antwerp (UA) | Department of Biology (Ethology) ; University of Antwerp (UA) | Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC) ; La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Department of Biology (Ethology) ; University of Antwerp (UA) | ANR-16-CE02-0004,URBASTRESS,Influence de l'urbanisation sur les populations de vertébrés: une approche éco-physiologique(2016)
International audience | Artificial light at night (ALAN) can disrupt adaptive patterns of physiology and behavior that promote high fitness, resulting in physiological stress and elevation of steroid glucocorticoids (corticosterone, CORT in birds). Elevated CORT may have particularly profound effects early in life, with the potential for enduring effects that persist into adulthood. Research on the consequences of early-life exposure to ALAN remains limited, especially outside of the laboratory, and the effects of early-life light exposure on CORT concentrations in wild nestling birds remain to be elucidated. We used an experimental setup to test the hypothesis that ALAN elevates CORT concentrations in developing free-living birds, by exposing nestling great tits (Parus major) to ALAN inside nest boxes. We measured CORT in feathers grown over the timeframe of the experiment (7 nights), such that CORT concentrations represent an integrative metric of hormone release over the period of nocturnal light exposure, and of development. We also assessed the relationships between feather CORT concentrations, body condition, nestling size rank and fledging success. In addition, we evaluated the relationship between feather CORT concentrations and telomere length. Nestlings exposed to ALAN had higher feather CORT concentrations than control nestlings, and nestlings in poorer body condition and smaller brood members also had higher CORT. On the other hand, telomere length, fledging success, and recruitment rate were not significantly associated with light exposure or feather CORT concentrations. Results indicate that exposure to ALAN elevates CORT concentrations in nestlings, which may reflect physiological stress. In addition, the organizational effects of CORT are known to be substantial. Thus, despite the lack of effect on telomere length and survivorship, elevated CORT concentrations in nestlings exposed to ALAN may have subsequent impacts on later-life fitness and stress sensitivity.
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