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Pb isotopes as tracers of mining-related Pb in lichens, seaweed and mussels near a former Pb-Zn mine in West Greenland
2010
Søndergaard, Jens | Asmund, Gert | Johansen, Poul | Elberling, Bo
Identification of mining-related contaminants is important in order to assess the spreading of contaminants from mining as well as for site remediation purposes. This study focuses on lead (Pb) contamination in biota near the abandoned ‘Black Angel Mine’ in West Greenland in the period 1988-2008. Stable Pb isotope ratios and total Pb concentrations were determined in lichens, seaweed and mussels as well as in marine sediments. The results show that natural background Pb (207Pb/206Pb: 0.704-0.767) and Pb originating from the mine ore (207Pb/206Pb: 0.955) have distinct isotopic fingerprints. Total Pb in lichens, seaweed, and mussels was measured at values up to 633, 19 and 1536 mg kg-1 dry weight, respectively, and is shown to be a mixture of natural Pb and ore-Pb. This enables quantification of mining-related Pb and shows that application of Pb isotope data is a valuable tool for monitoring mining pollution.
显示更多 [+] 显示较少 [-]The Case of Pollution of Lake Maggiore: a 12-Year Study with the Bioindicator Mussel Dreissena polymorpha
2010
Riva, Consuelo | Binelli, Andrea | Parolini, Marco | Provini, Alfredo
In 1996, dichlorodiphenyltrichloroethane (DDT) pollution of industrial origin was discovered in Lake Maggiore. It was caused by industrial effluents on a tributary of the River Toce, one of the major affluents of the lake in correspondence of Pallanza Bay. This event is the worst case of environmental pollution that has occurred in Western countries in the last 25 years, not due to agricultural use of DDT, but because of an accidental industrial discharge. Heavy polychlorinated biphenyls (PCBs) pollution was also noticed in 2002, with concentration levels three to seven times higher than those measured in other Italian subalpine lakes. In this study, the current DDT and PCBs contamination levels were assessed according to their presence in zebra mussel (Dreissena polymorpha) specimens sampled in the last 5 years (2003-2008) in eight sampling stations of Lake Maggiore, chosen to cover the entire perimeter of the basin. Moreover, for two stations (Baveno and Pallanza-Villa Taranto) located inside and outside Pallanza Bay, respectively, it is possible to make comparisons starting from 1996. The results obtained show how Lake Maggiore is still an ecosystem with a severe environmental risk, more than 10 years after the original insecticide discharge. DDT contamination continues to evolve, and natural events, like lake overturn, floods, and heavy rains, can have a great influence on the insecticide levels in the lake. By contrast, PCB contamination is absolutely negligible, even if the peak of pollution revealed in 2002 seems to indicate that these pollutants are still present in large quantities in the Lake Maggiore watershed.
显示更多 [+] 显示较少 [-]Assessment of low-level metal contamination using the Mediterranean mussel gills as the indicator tissue
2010
Dragun, Zrinka | Erk, Marijana | Ivanković, Dušica | Žaja, Roko | Filipović Marijić, Vlatka | Raspor, Biserka
Purpose The aim of this study was to compare the level of metal contamination in two bays in the middle part of the Eastern Adriatic coastal zone in Croatia using the gills of mussels Mytilus galloprovincialis as indicator tissue. Despite the existing sources of contamination, previous studies with caged mussels only indicated moderate metal contamination of the Kaštela Bay, contrary to the Trogir Bay in which marina and shipyard present a probable source of Cu- and Zn-contamination. Methods The measurements of metallothioneins (MTs) and metals that induce MT synthesis (Cu, Zn, and Cd) were performed in the heat-treated gill cytosol and total proteins (TPs) in the untreated gill cytosol. MTs were determined by differential pulse voltammetry, Cu and Zn by flame atomic absorption spectrometry (AAS), Cd by graphite furnace AAS, and TPs by Bradford spectrophotometric procedure. Results The results collected in four sampling campaigns (autumn periods from 2001 to 2004) indicated that MT levels in mussel gills (expressed on dry mass basis 2.3 ± 0.3 mg g⁻¹) were comparable with basal levels reported in the literature (2.5 ± 0.8 mg g⁻¹). Observed interindividual, temporal, and spatial MT variability could be associated with different confounding factors, such as the time of sampling, total protein concentration, and mussel size rather than cytosolic levels of Cu and Zn. Metal levels, expressed on wet mass basis, in the heat-treated gill cytosol ranged from 1.33 to 11.31 μg g⁻¹ for Zn, from 0.72 to 2.96 μg g⁻¹ for Cu, and from 0.036 to 0.100 μg g⁻¹ for Cd. The highest Zn level was measured at Vranjic (Kaštela Bay)—the site influenced by untreated domestic wastewater, while somewhat increased Zn and the highest Cu levels were found at marina and shipyard locations (Trogir Bay). The highest Cd level was measured at Inavinil (Kaštela Bay). Conclusions The observed association of gill MT levels with several biotic and abiotic factors limits its use as the biomarker of low-level metal exposure. Therefore, the use of the metal concentrations in the heat-treated gill cytosol of Mediterranean mussels should be considered for the assessment of the low-level metal contamination of coastal marine areas.
显示更多 [+] 显示较少 [-]Twenty years of elemental analysis of marine biota within the German Environmental Specimen Bank—a thorough look at the data
2010
Rüdel, Heinz | Fliedner, Annette | Kösters, Jan | Schröter-Kermani, Christa
Purpose As one component of the German ecological environment observation, the Environmental Specimen Bank program was initiated in the mid-1980s. Under the program, representative specimens of marine, fresh water, and terrestrial ecosystems are sampled regularly and archived under chemically stable conditions. An initial characterization of the samples provides data regarding the status quo of the respective ecosystems. The aim of the present publication is to give insight into these real-time monitoring data, which have been generated for the last 10 to 20 years. This is done exemplarily for the heavy metals cadmium (Cd), mercury (Hg), and lead (Pb) in marine specimens of the Baltic and the North Sea. Methods Bladder wrack (Fucus vesiculosus), blue mussel (Mytilus edulis), eelpout (Zoarces viviparus), and eggs of herring gulls (Larus argentatus) were sampled at one location in the Baltic Sea and at two sites in the North Sea (Schleswig-Holstein Wadden Sea and Lower Saxony Wadden Sea). Annual samples were pooled, homogenized, and analyzed for a set of elements. Cd and Pb were quantified after freeze-drying and microwave digestion using inductively coupled plasma-mass spectrometry. Total Hg in freeze-dried samples was determined by atomic absorption spectrometry using a direct mercury analyzer. Results Time series data covering up to two decades revealed comparable cadmium levels at all three locations. Concentrations in bladder wrack ranged between 0.10 and 0.37 µg/g on a wet weight basis (ww). Respective values for blue mussel and eelpout liver were 0.07-0.29 and 0.01-0.10 µg/g ww. Herring gull eggs were not included in cadmium analyses. Declining trends were observed in North Sea bladder wrack and mussels, eelpout from the Lower Saxony site, and mussels from the Baltic Sea. Upward trends were apparent in eelpout from the Schleswig-Holstein location. Mercury concentrations in Baltic Sea specimens ranged from 1.1-2.7 ng/g ww in bladder wrack to 2.6-5.1, 26-52, and 86-226 ng/g ww in blue mussel, eelpout muscle, and herring gull eggs, respectively. No temporal trends were observed. North Sea bladder wrack had accumulated 5.4-24 ng/g ww Hg. The respective Hg values for blue mussel and eelpout muscle were 19-64 and 73-187 ng/g ww. Highest Hg contents were detected in herring gull eggs (90-1,100 ng/g ww). Declining trends of Hg were observed in herring gull eggs at both North Sea locations and in blue mussels at the Lower Saxony site. Lead concentrations in Baltic Sea specimens were 48-222 ng/g ww in bladder wrack, 85-189 ng/g ww in blue mussel, 2.0-9.5 and 10-42 ng/g ww in eelpout muscle and liver, and 2.7-26 ng/g ww in herring gull eggs. In the North Sea, Pb concentrations were as follows: 68-397 ng/g ww in bladder wrack, 101-507 ng/g ww in blue mussels, 2.6-35 and 5.9-158 ng/g ww in eelpout muscle and liver, and 3.5-55 ng/g ww in herring gull eggs. Highest Pb-levels were found at the Lower Saxony site. Declining Pb-trends were observed in bladder wrack from the Baltic Sea; in bladder wrack and mussel at the Schleswig-Holstein location; and in bladder wrack, mussels, eelpout liver, and herring gull eggs at the Lower Saxony site. Conclusions During the 10 to 20 years of monitoring, reliable data were obtained which allow a good insight into metal contamination of marine biota. Assessment of the data according to OSPAR criteria (OSPAR 2005) revealed cadmium levels above the derived background concentrations in mussels of all three sites. Mercury levels above background concentrations were found at both North Sea locations, whereas only mussels at the Lower Saxony site had Pb concentrations above the reference value. Archived specimens are available for further analyses and questions which may arise in the future (speciation of elements, metallomics).
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