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Using risk-ranking of metals to identify which poses the greatest threat to freshwater organisms in the UK
2014
Donnachie, Rachel L. | Johnson, Andrew C. | Moeckel, Claudia | Pereira, M Glória | Sumpter, John P.
Freshwater aquatic organisms face the challenge of being exposed to a multitude of chemicals discharged by the human population. The objective of this study was to rank metals according to the threat they pose to aquatic organisms. This will contribute to a wider Chemical Strategy for freshwater which will risk-rank all chemicals based on their potential risk to wildlife in a UK setting. The method involved comparing information on ecotoxicological thresholds with measured concentrations in rivers. The bioconcentration factor was also considered as a ranking method. The metals; Ag, Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb and Zn, were analysed using this approach. Triclosan and lindane were used as comparative organic pollutants. Using a range of ranking techniques, Cu, Al and Zn came top of the list of concern, with Cu coming first.
Mostrar más [+] Menos [-]Causes of coastal waters pollution with nutrients, chemicals and plastics worldwide
2024
Micella, Ilaria | Kroeze, Carolien | Bak, Mirjam P. | Strokal, Maryna
Worldwide, coastal waters contain pollutants such as nutrients, plastics, and chemicals. Rivers export those pollutants, but their sources are not well studied. Our study aims to quantify river exports of nutrients, chemicals, and plastics to coastal waters by source and sub-basin worldwide. We developed a new MARINA-Multi model for 10,226 sub-basins. The global modelled river export to seas is approximately 40,000 kton of nitrogen, 1,800 kton of phosphorous, 45 kton of microplastics, 490 kton of macroplastics, 400 ton of triclosan and 220 ton of diclofenac. Around three-quarters of these pollutants are transported to the Atlantic and Pacific oceans. Diffuse sources contribute by 95–100 % to nitrogen (agriculture) and macroplastics (mismanaged waste) in seas. Point sources (sewage) contribute by 40–95 % to phosphorus and microplastics in seas. Almost 45 % of global sub-basin areas are multi-pollutant hotspots hosting 89 % of the global population. Our findings could support strategies for reducing multiple pollutants in seas.
Mostrar más [+] Menos [-]Residual additives in marine microplastics and their risk assessment – A critical review
2022
Fauser, Patrik | Vorkamp, Katrin | Strand, Jakob
This review summarizes the current state of knowledge regarding the risk assessment of plastic-associated residual additives, i.e. residual monomers, degradation products and additives, in the marine environment, also considering effects of weathering and bioavailability. Experimental studies have found a number of organic and metal additive compounds in leachates from plastics, and the analysis of weathered plastic particles, such as polyethylene, polypropylene and polystyrene particles sampled on beaches and shorelines, has identified residual additives, such as flame retardants, plasticizers, UV stabilizers and antioxidants. While the transfer of e.g. PBDEs to organisms upon ingestion has been demonstrated, studies on uptake and bioaccumulation of plastic-associated chemicals are inconclusive. Studies on hazard and risk assessments are few, and focus on monomers and/or a limited number of high concentration additives, such as phthalates and flame retardants. The risk assessment results vary between low, moderate and high risks of specific additives, and are not necessarily consistent for the same compound. Given the large number of chemicals potentially introduced into the marine environment with plastic particles and the challenges associated with the correct quantification of exposure concentrations and toxicity thresholds, the question arises whether new risk assessment concepts may be needed.
Mostrar más [+] Menos [-]Spatial distribution and biological effects of trace metals (Cu, Zn, Pb, Cd) and organic micropollutants (PCBs, PAHs) in mussels Mytilus galloprovincialis along the Algerian west coast
2017
Benali, Imene | Boutiba, Zitouni | Grandjean, Dominique | de Alencastro, Luiz Felippe | Rouane-Hacene, Omar | Chèvre, Nathalie
Native mussels Mytilus galloprovincialis are used as bioindicator organisms to assess the concentration levels and toxic effects of persistent chemicals, polychlorobiphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and heavy metals using biomarker responses, such as catalase (CAT), glutathione s-transferase (GST), and condition indices, for the Algerian coast. The results show that mussels of Oran Harbour are extremely polluted by PCBs and PAHs, i.e., 97.6 and 2892.1μg/kg d.w., respectively. Other sites present low levels of pollution. Furthermore, high concentrations of zinc, lead and cadmium are found in mussels from fishing, agricultural and estuarine sites, respectively, while low concentrations of copper are found in all of the sites studied. CAT activity is negatively correlated with Cd and Cu, and Zn is positively correlated with GST and CAT. Site classification tools reveal the potential toxicity of coastal areas exposed to anthropogenic pressure and a gradient of toxicity along the Algerian west coast.
Mostrar más [+] Menos [-][Detection of degradation products using chemical and biological methods [intrinsic bioremediation]]
1997
Dyreborg, S.
The nitrogen reduction programme in the Federal Republic of Germany
1998
Eichler, F. | Schulz, D. (Federal Environmental Agency, Bismarckplatz 1, D-14 193 Berlin (Germany))
EMEP eulerian model for atmospheric transport and deposition of nitrogen species over Europe
1998
Jonson, J.E. | Bartnicki, J. | Olendrzynski, K. | Jakobsen, H.A. | Berge, E. (Meteorological Synthesizing Centre - West of EMEP, The Norwegian Meteorological Institute, P.O. Box 43, Blindern N-0313 Oslo (Norway))
Emission reduction scenarios for nitrogen compounds and their impact on acidification, eutrophication and ozone formation in Flanders
1998
Mensink, C. | Beirens, F. (VITO, Boeretang 200, B-2400 Mol (Belgium))
Polycyclic aromatic hydrocarbon (PAH) dispersion and deposition to vegetation and soil following a large scale chemical fire
1998
Meharg, A.A. | Wright, J. | Dyke, H. | Osborn, D. (Institute of Terrestrial Ecology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire PE17 2LS (United Kingdom))