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Assessment of successful experiments and limitations of phytotechnologies : contaminant uptake, detoxification and sequestration, and consequences for food safety Texte intégral
2009
Mench, Michel | Schwitzguebel, Jean-Paul | Schroeder, Peter | Bert, Valérie | Gupta, Satish | Gawronski, Stanislaw | Biodiversité, Gènes & Communautés (BioGeCo) ; Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB) | Laboratory for Environmental Biotechnology | Department Microbe - Plant Interactions ; Helmholtz Zentrum München = German Research Center for Environmental Health (HMGU) | Institut National de l'Environnement Industriel et des Risques (INERIS) | Agroscope FAL Reckenholz ; Swiss Federal Research Station for Agroecology and Agriculture | Laboratory of Basic Research in Horticulture ; Warsaw University of Life Sciences (SGGW)
COST ACTION 859 | International audience | PURPOSE: The term "phytotechnologies" refers to the application of science and engineering to provide solutions involving plants, including phytoremediation options using plants and associated microbes to remediate environmental compartments contaminated by trace elements (TE) and organic xenobiotics (OX). An extended knowledge of the uptake, translocation, storage, and detoxification mechanisms in plants, of the interactions with microorganisms, and of the use of "omic" technologies (functional genomics, proteomics, and metabolomics), combined with genetic analysis and plant improvement, is essential to understand the fate of contaminants in plants and food, nonfood and technical crops. The integration of physicochemical and biological understanding allows the optimization of these properties of plants, making phytotechnologies more economically and socially attractive, decreasing the level and transfer of contaminants along the food chain and augmenting the content of essential minerals in food crops. This review will disseminate experience gained between 2004 and 2009 by three working groups of COST Action 859 on the uptake, detoxification, and sequestration of pollutants by plants and consequences for food safety. Gaps between scientific approaches and lack of understanding are examined to suggest further research and to clarify the current state-of-the-art for potential end-users of such green options. CONCLUSION AND PERSPECTIVES: Phytotechnologies potentially offer efficient and environmentally friendly solutions for cleanup of contaminated soil and water, improvement of food safety, carbon sequestration, and development of renewable energy sources, all of which contribute to sustainable land use management. Information has been gained at more realistic exposure levels mainly on Cd, Zn, Ni, As, polycyclic aromatic hydrocarbons, and herbicides with less on other contaminants. A main goal is a better understanding, at the physiological, biochemical, and molecular levels, of mechanisms and their regulation related to uptake-exclusion, apoplastic barriers, xylem loading, efflux-influx of contaminants, root-to-shoot transfer, concentration and chemical speciation in xylem/phloem, storage, detoxification, and stress tolerance for plants and associated microbes exposed to contaminants (TE and OX). All remain insufficiently understood especially in the case of multiple-element and mixed-mode pollution. Research must extend from model species to plants of economic importance and include interactions between plants and microorganisms. It remains a major challenge to create, develop, and scale up phytotechnologies to market level and to successfully deploy these to ameliorate the environment and human health
Afficher plus [+] Moins [-]Impact of the Phaeocystis globosa spring bloom on the intertidal benthic compartment in the eastern English Channel: A synthesis Texte intégral
2009
Spilmont, Nicolas | Denis, Lucie | Artigas, Luis Felipe | Caloin, Frederic | Courcot, Lucie | Creach, Anne | Desroy, Nicolas | Gevaert, Francois | Hacquebart, Pascal | Hubas, Cedric | Janquin, Marie-andree | Lemoine, Yves | Luczak, Christophe | Migne, Aline | Rauch, Mathieu | Davoult, Dominique
From 1999 to 2005, studies carried out in the frame of regional and national French programs aimed to determine whether the Phaeocystis globosa bloom affected the intertidal benthic communities of the French coast of the eastern English Channel in terms of composition and/or functioning. Study sites were chosen to cover most of the typical shore types encountered on this coast (a rocky shore, an exposed sandy beach and a small estuary). Both the presence of active Phaeocystis cells and their degradation product (foam) did have a significant impact on the studied shores. The primary production and growth rates of the kelp Saccharina latissima decreased during the bloom because of a shortage of fight and nutrient for the macroalgae. On sandy sediments, the benthic metabolism (community respiration and community primary production), as well as the nitrification rate, were enhanced during foam deposits, in relation with the presence of bacteria and active pelagic cells within the decaying colonies. In estuarine sediments, the most impressive impact was the formation of a crust at the sediment surface due to drying foam. This led to anoxic conditions in the surface sediment and resulted in a high mortality among the benthic community. Some organisms also tended to migrate upward and were then directly accessible to the higher trophic level represented by birds. Phaeocystis then created a shortcut in the estuarine trophic network. Most of these modifications lasted shortly and all the systems considered came back to their regular properties and activities a few weeks after the end of the bloom, except for the most impacted estuarine area. (C) 2008 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]Sublethal effects of herbicides on the biomass and seed production of terrestrial non-crop plant species, influenced by environment, development stage and assessment date Texte intégral
2009
Riemens, M.M. | Dueck, T.A. | Kempenaar, C. | Lotz, L.A.P. | Kropff, M.J.
Guidelines provided by the OECD and EPPO allow the use of single-species tests performed in greenhouses to assess the risk of herbicides to non-target terrestrial plant communities in the field. The present study was undertaken to investigate the use of greenhouse data to determine effects of herbicides with a different mode of action on the biomass, seed production and emergence of field-grown plants. In addition, a single species approach was compared with a mixed species approach. Effects on the biomass of greenhouse and field-grown plants were found to be related at different effect levels, indicating that it might be possible to translate results from greenhouse studies to field situations. However, the use of single-species tests may not be valid. The response of a single plant species to sublethal herbicide dosages differed to the response of the same species grown in a mixture with other species. The use of single-species greenhouse tests in the ecological risk assessment of crop protection products may only be valid for single species in the field, not for vegetations. Keywords: Non-crop terrestrial plants; Tepraloxydim; Greenhouse; Field; Biomass
Afficher plus [+] Moins [-]Fate of polybrominated diphenyl ethers in the environment of the Pearl River Estuary, South China Texte intégral
2009
Guan, Yu-Feng | Sojinu, O.S Samuel | Li, Shao-Meng | Zeng, E. Y. (Eddy Y)
Ninety-six riverine runoff samples collected at eight major outlets in the Pearl River Delta (PRD), South China, during 2005-2006 were analyzed for 17 brominated diphenyl ether (BDE) congeners (defined as Σ17PBDE). Fourteen and 15 congeners were detected, respectively, in the dissolved and particulate phases. These data were further used to elucidate the partitioning behavior of BDE congeners in riverine runoff. Several related fate processes, i.e. air-water exchange, dry and wet deposition, degradation, and sedimentation, within the Pearl River Estuary (PRE), were examined to estimate the inputs of Σ10PBDE (sum of the target BDE congeners, BDE-28, -47, -66, -85, -99, -100, -138, -153, -154, and -183) and BDE-209 from the PRD to the coastal ocean based on mass balance considerations. The results showed that annual outflows of Σ10PBDE and BDE-209 were estimated at 126 and 940 kg/year, respectively from the PRE to coastal ocean. Besides sedimentation and degradation, the majority of Σ10PBDE and BDE-209 discharged into the PRE via riverine runoff was transported to the coastal ocean. Fate of polybrominated diphenyl ethers in the environment the Pearl River Estuary, South China.
Afficher plus [+] Moins [-]Iron-rich dune grasslands: Relations between soil organic matter and sorption of Fe and P Texte intégral
2009
Kooijman, A.M. | Lubbers, I. | Til, M van
Effects of high atmospheric nitrogen-deposition partly depend on availability of phosphate. Lime-poor, but iron-rich dune grasslands are supposedly protected from grass-encroachment, due to P-fixation in iron phosphate. However, in iron-rich Dutch hinterdunes, dunes have low, but dry former beach plains high grass-encroachment. To test whether these zones differ in nutrient availability, and whether this changed with duration of grass-encroachment, we measured net N-mineralization, microbial characteristics and different fractions of P and Fe from pioneer and shortgrass to tallgrass stages approximately 10, 20 and >25 years old. N-mineralization did not differ between zones, but increased in older tallgrass stages in the organic layer. P-availability was significantly lower in the low grass-encroachment zone, with SOM values below 3% and mineral Fe above 40% allowing for P-fixation in iron phosphates. In the high grass-encroachment zone, however, P-availability increased, because SOM increased and Fe became incorporated in organic matter complexes, with more reversible P-sorption. Iron-rich dune grasslands may be protected from high N-deposition and grass-encroachment only when SOM is low, because only then P-fixation in iron phosphates occurs.
Afficher plus [+] Moins [-]Organochlorines in the Vaccarès Lagoon trophic web (Biosphere Reserve of Camargue, France) Texte intégral
2009
Roche, H. | Vollaire, Y. | Persic, A. | Buet, A. | Oliveira-Ribeiro, C. | Coulet, E. | Banas, D. | Ramade, F.
Organochlorines in the Vaccarès Lagoon trophic web (Biosphere Reserve of Camargue, France) Texte intégral
2009
Roche, H. | Vollaire, Y. | Persic, A. | Buet, A. | Oliveira-Ribeiro, C. | Coulet, E. | Banas, D. | Ramade, F.
During a decade (1996-2006), ecotoxicological studies were carried out in biota of the Vaccarès Lagoon (Biosphere Reserve in Rhone Delta, France). A multicontamination was shown at all levels of the trophic web due to a direct bioconcentration of chemical from the medium combined with a food transfer. Here, the pollutants investigated were organochlorines, among which many compounds banned or in the course of prohibition (or restriction) (PCB, lindane, pp'-DDE, dieldrin, aldrin, heptachlor, endosulfan ...) and some substances likely still used in the Rhone River basin (diuron, fipronil). The results confirmed the ubiquity of contamination. It proves to be chronic, variable and tends to regress; however contamination levels depend on the trophic compartment. A biomagnification process was showed. A comparison of investigation methods used in other Mediterranean wetlands provides basis of discussion, and demonstrates the urgent need of modelling to assess the ecotoxicological risk in order to improve the management of such protected areas. The Vaccarès Lagoon trophic web biomagnifies organochlorine pollutants.
Afficher plus [+] Moins [-]Organochlorines in the Vaccarès Lagoon trophic web (Biosphere Reserve of Camargue, France) Texte intégral
2009
Roche, Hélène | Vollaire, Y. | Persic, A. | Buet, A. | Oliveira-Ribeiro, C. | Coulet, E. | Banas, Damien | Ramade, F.
During a decade (1996–2006), ecotoxicological studies were carried out in biota of the Vaccarès Lagoon (Biosphere Reserve in Rhone Delta, France). A multicontamination was shown at all levels of the trophic web due to a direct bioconcentration of chemical from the medium combined with a food transfer. Here, the pollutants investigated were organochlorines, among which many compounds banned or in the course of prohibition (or restriction) (PCB, lindane, pp′-DDE, dieldrin, aldrin, heptachlor, endosulfan…) and some substances likely still used in the Rhone River basin (diuron, fipronil). The results confirmed the ubiquity of contamination. It proves to be chronic, variable and tends to regress; however contamination levels depend on the trophic compartment. A biomagnification process was showed. A comparison of investigation methods used in other Mediterranean wetlands provides basis of discussion, and demonstrates the urgent need of modelling to assess the ecotoxicological risk in order to improve the management of such protected areas. The Vaccarès Lagoon trophic web biomagnifies organochlorine pollutants.
Afficher plus [+] Moins [-]Organochlorines in the Vaccarès Lagoon trophic web (Biosphere Reserve of Camargue, France) Texte intégral
2009
Roche, Hélène | Vollaire, Y. | Persic, A. | Buet, A. | Oliveira-Ribeiro, C. | Coulet, E. | Banas, Damien | Ramade, F. | Ecologie Systématique et Evolution (ESE) ; Université Paris-Sud - Paris 11 (UP11)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS) | Universidade Federal do Paraná [Curitiba, Brasil] = Federal University of Paraná [Curitiba, Brazil] = Université fédérale du Paraná [Curitiba, Brésil] (UFPR) | Réserve Nationale de Camargue ; Réserve Naturelle Nationale de Camargue ; Réserves Naturelles de France-Réserves Naturelles de France | Unité de Recherches Animal et Fonctionnalités des Produits Animaux (URAFPA) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL)
International audience | During a decade (1996–2006), ecotoxicological studies were carried out in biota of the Vaccarès Lagoon (Biosphere Reserve in Rhone Delta, France). A multicontamination was shown at all levels of the trophic web due to a direct bioconcentration of chemical from the medium combined with a food transfer. Here, the pollutants investigated were organochlorines, among which many compounds banned or in the course of prohibition (or restriction) (PCB, lindane, pp′-DDE, dieldrin, aldrin, heptachlor, endosulfan…) and some substances likely still used in the Rhone River basin (diuron, fipronil). The results confirmed the ubiquity of contamination. It proves to be chronic, variable and tends to regress; however contamination levels depend on the trophic compartment. A biomagnification process was showed. A comparison of investigation methods used in other Mediterranean wetlands provides basis of discussion, and demonstrates the urgent need of modelling to assess the ecotoxicological risk in order to improve the management of such protected areas. The Vaccarès Lagoon trophic web biomagnifies organochlorine pollutants.
Afficher plus [+] Moins [-]Evaluation of approaches to calculate critical metal loads for forest ecosystems Texte intégral
2009
Vries, W de | Groenenberg, J.E.
This paper evaluates approaches to calculate acceptable loads for metal deposition to forest ecosystems, distinguishing between critical loads, stand-still loads and target loads. We also evaluated the influence of including the biochemical metal cycle on the calculated loads. Differences are illustrated by examples of Cd, Cu, Pb and Zn for a deciduous forest on five major soil types in the Netherlands. Stand-still loads are generally lower than critical loads, which in turn are lower than the target loads indicating that present levels are below critical levels. Uncertainties in the calculated critical loads are mainly determined by the uncertainty in the critical limits and the chemical speciation model. Including the metal cycle has a small effect on the calculated critical loads. Results are discussed in view of the applicability of the critical load concept for metals in future protocols on the reduction in metal emissions. Critical load methods for metals can be used to assess future risks due to metal inputs.
Afficher plus [+] Moins [-]Progestagens for human use, exposure and hazard assessment for the aquatic environment Texte intégral
2009
Besse, Jean-Philippe | Garric, Jeanne
Little information is available on the environmental occurrence and ecotoxicological effects of pharmaceutical gestagens released in the aquatic environment. Since eighteen different gestagens were found to be used in France, preliminary exposure and hazard assessment were done. Predicted environmental concentrations (PECs) suggest that if parent gestagens are expected to be found in the ng l−1 range, some active metabolites could be present at higher concentrations, although limited data on metabolism and environmental fate limit the relevance of PECs. The biological effects are not expected to be restricted to progestagenic activity. Both anti-androgenic activity (mainly for cyproterone acetate, chlormadinone acetate and their metabolites) and estrogenic activity (mainly for reduced metabolites of levonorgestrel and norethisterone) should also occur. All these molecules are likely to have a cumulative effect among themselves or with other xenoestrogens. Studies on occurrence, toxicity and degradation time are therefore needed for several of these compounds. Gestagens exposure and hazard assessment for the aquatic environment.
Afficher plus [+] Moins [-]Model evaluation of the phytoextraction potential of heavy metal hyperaccumulators and non-hyperaccumulators Texte intégral
2009
Liang, Hong-Ming | Lin, Ting-Hsiang | Chiou, Jeng-Min | Ye, Guozhen
Evaluation of the remediation ability of zinc/cadmium in hyper- and non-hyperaccumulator plant species through greenhouse studies is limited. To bridge the gap between greenhouse studies and field applications for phytoextraction, we used published data to examine the partitioning of heavy metals between plants and soil (defined as the bioconcentration factor). We compared the remediation ability of the Zn/Cd hyperaccumulators Thlaspi caerulescens and Arabidopsis halleri and the non-hyperaccumulators Nicotiana tabacum and Brassica juncea using a hierarchical linear model (HLM). A recursive algorithm was then used to evaluate how many harvest cycles were required to clean a contaminated site to meet Taiwan Environmental Protection Agency regulations. Despite the high bioconcentration factor of both hyperaccumulators, metal removal was still limited because of the plants' small biomass. Simulation with N. tabacum and the Cadmium model suggests further study and development of plants with high biomass and improved phytoextraction potential for use in environmental cleanup. A quantitative solution enables the evaluation of Zn/Cd phytoextraction.
Afficher plus [+] Moins [-]Classification of nutrient emission sources in the Vistula River system Texte intégral
2009
Kowalkowski, Tomasz
Eutrophication of the Baltic sea still remains one of the biggest problems in the north-eastern area of Europe. Recognizing the sources of nutrient emission, classification of their importance and finding the way towards reduction of pollution are the most important tasks for scientists researching this area. This article presents the chemometric approach to the classification of nutrient emission with respect to the regionalisation of emission sources within the Vistula River basin (Poland). Modelled data for mean yearly emission of nitrogen and phosphorus in 1991-2000 has been used for the classification. Seventeen subcatchements in the Vistula basin have been classified according to cluster and factor analyses. The results of this analysis allowed determination of groups of areas with similar pollution characteristics and indicate the need for spatial differentiation of policies and strategies. Three major factors indicating urban, erosion and agricultural sources have been identified as major discriminants of the groups. Two classification methods applied to evaluate the results of nutrient emission allow definition of major sources of the emissions and classification of catchments with similar pollution.
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