خيارات البحث
النتائج 2051 - 2060 من 62,084
A mixture of persistent organic pollutants relevant for human exposure inhibits the transactivation activity of the aryl hydrocarbon receptor in vitro
2019
Doan, Thi-Que | Berntsen, Hanne | Verhaegen, Steven | Ropstad, Erik | Connolly, Lisa | Igout, Ahmed | Muller, Marc | Scippo, Marie-Louise | FARAH - Fundamental and Applied Research for Animals and Health - ULiège | GIGA-I3 - Giga-Infection, Immunity and Inflammation - ULiège
peer reviewed
اظهر المزيد [+] اقل [-]A Bayesian network approach for the identification of relationships between drivers of chlordecone bioaccumulation in plants
2019
Liber, Yohan | Cornet, Denis | Tournebize, Régis | Feidt, Cyril | Mahieu, Maurice | Laurent, François | Bedell, Jean-Philippe
Plants were sampled from four different types of chlordecone-contaminated land in Guadeloupe (West Indies). The objective was to investigate the importance of biological and agri-environmental parameters in the ability of plants to bioaccumulate chlordecone. Among the plant traits studied, only the growth habit significantly affected chlordecone transfer, since prostrate plants concentrated more chlordecone than erect plants. In addition, intensification of land use has led to a significant increase in the amount of chlordecone absorbed by plants. The use of Bayesian networks uncovers some hypothesis and identifies paths for reflection and possible studies to identify and quantify relationships that explain our data.
اظهر المزيد [+] اقل [-]Mytilus spp. as sentinels for monitoring microplastic pollution in Norwegian coastal waters: A qualitative and quantitative study. | Mytilus spp. as sentinels for monitoring microplastic pollution in Norwegian coastal waters: A qualitative and quantitative study.
2018
Bråte, Inger Lise Nerland | Hurley, Rachel | Iversen, Karine | Beyer, Jonny | Thomas, Kevin V | Steindal, Calin Constantin | Green, Norman Whitaker | Olsen, Marianne | Lusher, Amy
Microplastic (MP) contamination is ubiquitous in the environment and many species worldwide have been shown to contain MP. The ecological impact of MP pollution is still unknown, thus there is an urgent need for more knowledge. One key task is to identify species suitable as sentinels for monitoring in key eco-compartments, such as coastal waters. In Norway, mussels (Mytilus spp.) have been monitored for hazardous contaminants through OSPAR since 1981. Norway has the longest coastline in Europe and adding MP to the Norwegian Mussel Watch is therefore important in a European and global context. The present study reports MP data in mussels (332 specimens) collected from multiple sites (n = 15) spanning the whole Norwegian coastline. MPs were detected at all locations, except at one site on the west coast. Among the most surprising findings, mussels from the Barents Sea coastline in the Finnmark region, contained significantly more MPs than mussels from most of the southern part of the country, despite the latter sites being located much closer to major urban areas. Only mussels from a site located very close to Oslo, the capital, contained levels similar to those observed in the remote site in Finnmark. In total an average of 1.5 (±2.3) particles ind−1 and 0.97 (±2.61) particles w.w. g−1 was found. The most common MPs were <1 mm in size, and fibres accounted for 83% of particles identified, although there was inter-site variability. Thirteen different polymeric groups were identified; cellulosic being the most common and black rubbery particles being the second. This study suggests Mytilus spp. are suitable for semi-quantitative and qualitatively monitoring of MPs in coastal waters. However, some uncertainties remain including mussel size as a confounding factor that may influence ingestion, the role of depuration and other fate related processes, and this call for further research. | publishedVersion
اظهر المزيد [+] اقل [-]Assessment of nitrogen and phosphorus pathways at the profile of over-fertilised alluvial soils. Implications for best management practices
2018
Salazar, Osvaldo | Fuentes, Ignacio | Seguel Seguel, Oscar | Nájera de Ferrari, Francisco | Casanova, M.
Contrasting soil profiles (coarse-textured and fine-textured) treated with brilliant blue (BB) dye tracer, inorganic nitrogen (N) and phosphorus (P) concentrations along and between stained preferential flow pathways were examined for an irrigated and overfertilised maize monoculture system at the Mediterranean central Chile. The PO4-P concentrations were 2- to 10-fold higher in areas with BB than in areas without BB below 0.5-m soil depth in both soils. This elevated concentration was attributed to transport through cracks in fine-textured soil and finger flow in coarse-textured soil. The highest PO4-P value (13 mg kg(-1)) was found in areas with BB at the fine-textured soil. There were no significant differences in inorganic N concentration between areas with and without BB for both soils, which suggest that the effects of preferential flow are less important for inorganic N forms. There was a strong significant (p < 0.01) positive correlation between PO4-P and NH4-N concentrations in the fine-textured soil, and the amounts retained were clearly proportional to the clay content. Strategies for reducing N and P losses must be placed on good agronomic management of irrigated maize cropping system including accurate calculation of N and P fertiliser rates and establishment of suitable mitigation measures such as cover cropping. | FONDECYT 1150572
اظهر المزيد [+] اقل [-]Chronic exposure to copper and zinc induces DNA damage in the polychaete Alitta virens and the implications for future toxicity of coastal sites
2018
Watson, G. J. | Pini, J. M. | Richir, Jonathan | Institute of Marine Sciences, School of Biological Sciences, University of Portsmouth
peer reviewed | Copper and zinc are metals that have been traditionally thought of as past contamination legacies. However, their industrial use is still extensive and current applications (e.g. nanoparticles and antifouling paints) have become additional marine environment delivery routes. Determining a pollutant's genotoxicity is an ecotoxicological priority, but in marine benthic systems putative substances responsible for sediment genotoxicity have rarely been identified. Studies that use sediment as the delivery matrix combined with exposures over life-history relevant timescales are also missing for metals. Here we assess copper and zinc's genotoxicity by exposing the ecologically important polychaete Alitta virens to sediment spiked with environmentally relevant concentrations for 9 months. Target bioavailable sediment and subsequent porewater concentrations reflect the global contamination range for coasts, whilst tissue concentrations, although elevated, were comparable with other polychaetes. Survival generally reduced as concentrations increased, but monthly analyses show that growth was not significantly different between treatments. The differential treatment mortality may have enabled the surviving worms in the high concentration treatments to capture more food thus removing any concentration treatment effects for biomass. Using the alkaline comet assay we confirm that both metals via the sediment are genotoxic at concentrations routinely found in coastal regions and this is supported by elevated DNA damage in worms from field sites. However, combined with the growth data it also highlights the tolerance of A. virens to DNA damage. Finally, using long term (decadal) monitoring data we show stable or increasing sediment concentrations of these metals for many areas. This will potentially mean coastal sediment is a significant mutagenic hazard to the benthic community for decades to come. An urgent reappraisal of the current input sources for these ‘old pollutants’ is, therefore, required. Chronic exposure of zinc and copper via sediment at environmentally relevant concentrations induces DNA damage in a marine polychaete. © 2018 Elsevier Ltd
اظهر المزيد [+] اقل [-]Possible emissions of POPs in plain and hilly areas of Nepal: Implications for source apportionment and health risk assessment
2017
Yadav, Ishwar chandra | Devi, Ningombam linthoingambi | Li, Jun | Zhang, Gan | Breivik, Knut
Ambient air is a core media chosen for monitoring under the Stockholm Convention on POPs. While extensive monitoring of POPs in ambient air has been carried out in some parts of the globe, there are still regions with very limited information available, such as some developing countries as Nepal. This study therefore aims to target the occurrence of selected POPs in Nepal in suspected source areas/more densely populated regions. Four potential source regions in Nepal were furthermore targeted as it was hypothesized that urban areas at lower altitudes (Birgunj and Biratnagar located at approximately 86 and 80 m.a.s.l.) would be potentially more affected by OCPs because of more intensive agricultural activities in comparison to urban areas at higher altitudes (Kathmandu, Pokhara located 1400 and 1135 m.a.s.l). As some of these areas could also be impacted by LRAT, air mass back trajectories during the sampling period were additionally evaluated using HYSPLIT. The concentrations of overall POPs were twice as high in plain areas in comparison to hilly areas. DDTs and HCHs were most frequently detected in the air samples. The high p,p'-DDT/(pp'-DDE + pp'-DDD) ratio as well as the low o,p'-DDT/p,p'-DDT ratio observed in this study was inferred as continuing use of technical DDT. High levels of Sum26PCBs were linked to proximity to highly urbanized and industrial areas, indicating the potential source of PCBs. The measured concentrations of legacy POPs in air from this study is assumed to represent a negligible health risk through inhalation of ambient air, however, other modes of human exposure could still be relevant in Nepal. The air mass backward trajectory analysis revealed that most of the air masses sampled originated from India and the Bay of Bengal. | acceptedVersion
اظهر المزيد [+] اقل [-]Environmental impact of non-certified versus certified (ASC) intensive Pangasius aquaculture in Vietnam, a comparison based on a statistically supported LCA
2016
Nhu, T.T. | Schaubroeck, T. | Henriksson, P.J.G. | Bosma, R. | Sorgeloos, P. | Dewulf, J.
Pangasius production in Vietnam is widely known as a success story in aquaculture, the fastest growing global food system because of its tremendous expansion by volume, value and the number of international markets to which Pangasius has been exported in recent years. While certification schemes are becoming significant features of international fish trade and marketing, an increasing number of Pangasius producers have followed at least one of the certification schemes recognised by international markets to incorporate environmental and social sustainability practices in aquaculture, typically the Pangasius Aquaculture Dialogue (PAD) scheme certified by the Aquaculture Stewardship Council (ASC). An assessment of the environmental benefit of applying certification schemes on Pangasius production, however, is still needed. This article compared the environmental impact of ASC-certified versus non-ASC certified intensive Pangasius aquaculture, using a statistically supported Life Cycle Assessment (LCA). We focused on both resource-related (water, land and total resources) and emissions-related (global warming, acidification, freshwater and marine eutrophication) categories.
اظهر المزيد [+] اقل [-]Etat actuel des réseaux de mesures éco-climatiques en Afrique Centrale : les ambitions du projet de recherché international FORGREENE
2016
Bigot, S. | Philippon, Nathalie | Gond, Valéry | Moron, Vincent | Pokam, Wilfried | Bayol, Nicolas | Boyemba Bosela, Faustin | Kahindo, B. | Samba, G. | Ngomanda, Alfred | Gapia, M. | Yongo, Olga Diane | Laurent, J.P. | Gourlet-Fleury, Sylvie | Doumenge, Charles | Forni, Eric | Camberlin, Pierre | Martiny, N. | Dubreuil, Vincent
Ce travail fait un état des lieux de la qualité temporelle et de la densité spatiale des séries pluviométriques du Cameroun, Gabon, Congo, RCA et RDC, en particulier sur la période récente (1973-2014) grâce à la base de données internationale GSOD. Face aux énormes lacunes observées, ces résultats vont permettre d'orienter les choix métrologiques et analytiques in situ du programme FORGREENE (Tropical forests greeness and cloudiness in Central Africa: present conditions and future evolution). Une comparaison avec des estimations satellitaires (de type RFE) indique aussi leur potentiel intéressant, à condition qu'elles s'appuient sur des validations in situ. (Résumé d'auteur)
اظهر المزيد [+] اقل [-]Emerging issue of e-waste in Pakistan: A review of status, research needs and data gaps
2015
Iqbal, Mehreen | Breivik, Knut | Syed, Jabir Hussain | Malik, Riffat Naseem | Li, Jun | Zhang, Gan | Jones, Kevin C.
This review article focuses on the current situation of e-waste in Pakistan with the emphasis on defining the major e-waste recycling sites, current and future domestic generation of e-waste, hidden flows or import of e-waste and discusses various challenges for e-waste management. Needed policy interventions and possible measures to be taken at governmental level are discussed to avoid the increasing problem of e-waste in the country. Our findings highlight that there is still a general lack of reliable data, inventories and research studies addressing e-waste related issues in the context of environmental and human health in Pakistan. There is therefore a critical need to improve the current knowledge base, which should build upon the research experience from other countries which have experienced similar situations in the past. Further research into these issues in Pakistan is considered vital to help inform future policies/control strategies as already successfully implemented in other countries. | acceptedVersion
اظهر المزيد [+] اقل [-]Endosulfan, pentachlorobenzene and short-chain chlorinated paraffins in background soils from Western Europe
2015
Halse, Anne Karine | Schlabach, Martin | Schuster, Jasmin K | Jones, Kevin C | Steinnes, Eiliv | Breivik, Knut
Soils are major reservoirs for many persistent organic pollutants (POPs). In this study, “newly” regulated POPs i.e. sum endosulfans (a-endosulfan, b-endosulfan, endosulfan sulfate), pentachlorobenzene (PeCB), and short-chain chlorinated paraffins (SCCPs) were determined in background samples from woodland (WL) and grassland (GL) surface soil, collected along an existing latitudinal UK-Norway transect. Statistical analysis, complemented with plots showing the predicted equilibrium distribution and mobility potential, was then explored to discuss factors controlling their spatial distribution. SCCPs were detected with the highest average concentrations (35 ± 100 ng/g soil organic matter (SOM)), followed by sum endosulfans (3 ± 3 ng/g SOM) and PeCB (1 ± 1 ng/g SOM). PeCB and sum endosulfans share many similarities in their distribution in these background soils as well as with several legacy POPs. A steep decline in concentrations of SCCPs with increasing latitude indicates that their occurrence is dictated by proximity to source regions, while concentrations of Sendosulfans peaked in regions experiencing elevated precipitation rates. | acceptedVersion
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