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Tidal influence on the distribution of hydrophobic organic contaminants in the Seine Estuary and biomarker responses on the copepod Eurytemora affinis Full text
2009
Cailleaud, K. | Forget-Leray, J. | Peluhet, L. | LeMenach, K. | Souissi, S. | Budzinski, H.
To elucidate tidally related variations of hydrophobic organic contaminant (HOC) bioavailability and the impact of these contaminants on estuarine ecosystems, both PCB and PAH concentrations were investigated in the dissolved phase and in the suspended particulate material (SPM) of the Seine Estuary. Both PAH and PCB highest levels were observed in surface and bottom water when SPM remobilizations were maximum, in relation to higher speed currents. In parallel, acetylcholinesterase (AChE) and glutathione-S-transferase (GST) activities were investigated in the copepod Eurytemora affinis. Significant decreasing AChE levels were measured during the tidal cycle and between surface and bottom copepods related to salinity and to HOC concentration variations. Significant increasing GST levels were also observed when HOC concentrations in the water column were the highest. This study underlined the need to standardize sampling procedures for biomonitoring studies in order to avoid interfering factors that could modify biomarker responses to chemical exposure. Variations of contamination of E. affinis and enzymatic responses have been studied over a tide cycle in view to improve the use of this copepod for biomonitoring.
Show more [+] Less [-]Detection of phosphorus species in sediments of artificial landscape lakes in China by fractionation and phosphorus-31 nuclear magnetic resonance spectroscopy Full text
2009
Liu, Jinyong | Wang, Hui | Yang, Haijun | Ma, Yanjun | Cai, Ouchen
Phosphorus (P) pollution in the sediments of seven artificial landscape lakes was studied via fractionation and phosphorus-31 nuclear magnetic resonance (31P NMR) spectroscopy. The lake sediments accumulated significant amounts of P from supplementation with reclaimed water and from runoff from the golf course lawns. The differences in total sediment P among lakes were correlated to the varied pollution extent from the lawns. One striking feature of the artificial lake sediments was the insufficiency of NaOH-extracted Al, which plays an important role in avoiding internal P release during anoxia. Another characteristic was the dominance of orthophosphate in the NaOH-EDTA extractants of the sediments, due to the heavy external P pollution. Phytate, considered prevalent in many soils and lake sediments, as well as polyphosphates and phosphonates which have appeared in some natural lake sediments, was not detected. The rank order of present biogenic P species was monoester-P > DNA-P > pyrophosphate > lipid-P. Mineral fixation and biological conversion of phosphorus were investigated in artificial lake sediments in China.
Show more [+] Less [-]Processing of antifouling paint particles by Mytilus edulis Full text
2009
Turner, Andrew | Barrett, Mark | Brown, M. T.
Particles of spent antifouling paint collected from a marine boatyard were ground and subsequently administered to the filter-feeding bivalve, Mytilus edulis, maintained in static aquaria. Concentrations of Cu and Zn were measured in seawater throughout a 16 h feeding phase and a 24 h depuration phase, in rejected and egested particles collected during the respective phases, and in the organisms themselves at the end of the experiments. Concentrations and distributions of Cu and Zn in processed particles indicated that M. edulis was able to ingest paint particles, regardless of whether nutritionally viable silt was present, and no mechanism of particle discrimination was evident. Enrichment of Cu and Zn in the visceral mass of individuals and in the aqueous phase during depuration supported these assertions, although elevated concentrations in other compartments of the organism (e.g. shell, gill) suggested that biotic and abiotic uptake of aqueous metal was also important. Particles of antifouling paint enriched in Cu and Zn are ingested and digested by the marine bivalve M. edulis.
Show more [+] Less [-]Leaching of hydrophobic Cu and Zn from discarded marine antifouling paint residues: Evidence for transchelation of metal pyrithiones Full text
2009
Holmes, Luke | Turner, Andrew
Leaching of Cu and Zn from a composite of discarded antifouling paint residues ([Cu] = 288 mg g−1; [Zn] = 96 mg g−1) into natural sea water has been studied over a period of 75 h. Total Cu and Zn were released according to a pseudo first-order reaction, with rate constants on the order of 0.3 and 2.5 (mg L−1)−1 h−1, respectively, and final concentrations equivalent to the dissolution of about 8 and 2% of respective concentrations in the composite. Time-distributions of hydrophobic metals, determined by solid phase extraction-methanol elution, were more complex. Net release of hydrophobic Cu was greater in the absence of light than under a sequence of light–dark cycles; however, hydrophobic Zn release was not detected under the former conditions but contributed up to 50% of total aqueous Zn when light was present. These observations are interpreted in terms of the relative thermodynamic and photolytic stabilities of biocidal pyrithione complexes. Hydrophobic Cu and Zn leached from antifouling paint particles into sea water appear to be pyrithione complexes.
Show more [+] Less [-]A simple chemical free arsenic removal method for community water supply – A case study from West Bengal, India Full text
2009
Sen Gupta, B. | Chatterjee, S. | Rott, U. | Kauffman, H. | Bandyopadhyay, A. | DeGroot, W. | Nag, N.K. | Carbonell-Barrachina, A.A. | Mukherjee, S.
This report describes a simple chemical free method that was successfully used by a team of European and Indian scientists (www.qub.ac.uk/tipot) to remove arsenic (As) from groundwater in a village in West Bengal, India. Six such plants are now in operation and are being used to supply water to the local population (www.insituarsenic.org). The study was conducted in Kasimpore, a village in North 24 Parganas District, approximately 25 km from Kolkata. In all cases, total As in treated water was less than the WHO guideline value of 10 μg L−1. The plant produces no sludge and the operation cost is 1.0 US$ per day for producing 2000 L of potable water. This work presents the chemical free arsenic removal method from groundwater and its successful implementation in West Bengal for community water supply.
Show more [+] Less [-]Assessing the genotoxicity of urban air pollutants using two in situ plant bioassays Full text
2009
Villarini, M. | Fatigoni, C. | Dominici, L. | Maestri, S. | Ederli, L. | Pasqualini, S. | Monarca, S. | Moretti, M.
Genotoxicity of urban air has been analysed almost exclusively in airborne particulates. We monitored the genotoxic effects of airborne pollutants in the urban air of Perugia (Central Italy). Two plant bioindicators with different genetic endpoints were used: micronuclei in meiotic pollen mother cells using Tradescantia-micronucleus bioassay (Trad-MCN) and DNA damage in nuclei of Nicotiana tabacum leaves using comet assay (Nicotiana-comet). Buds of Tradescantia clone # 4430 and young N. tabacum cv. Xanthi plants were exposed for 24 h at three sites with different pollution levels. One control site (indoor control) was also used. The two bioassays showed different sensitivities toward urban pollutants: Trad-MCN assay was the most sensitive, but DNA damage in N. tabacum showed a better correlation with the pollutant concentrations. In situ biomonitoring of airborne genotoxins using higher plants combined with chemical analysis is thus recommended for characterizing genotoxicity of urban air. Plant bioassays used to explore in situ the correlation between air pollution and genotoxicity.
Show more [+] Less [-]How do long-term development and periodical changes of river–floodplain systems affect the fate of contaminants? Results from European rivers Full text
2009
Lair, G.J. | Zehetner, F. | Fiebig, M. | Gerzabek, M.H. | Gestel, C.A.M van | Hein, T. | Hohensinner, S. | Hsu, P. | Jones, K.C. | Jordan, G. | Koelmans, A.A. | Poot, A. | Slijkerman, D.M.E. | Totsche, K.U. | Bondar-Kunze, E. | Barth, J.A.C.
In many densely populated areas, riverine floodplains have been strongly impacted and degraded by river channelization and flood protection dikes. Floodplains act as buffers for flood water and as filters for nutrients and pollutants carried with river water and sediment from upstream source areas. Based on results of the EU-funded “AquaTerra” project (2004–2009), we analyze changes in the dynamics of European river–floodplain systems over different temporal scales and assess their effects on contaminant behaviour and ecosystem functioning. We find that human-induced changes in the hydrologic regime of rivers have direct and severe consequences on nutrient cycling and contaminant retention in adjacent floodplains. We point out the complex interactions of contaminants with nutrient availability and other physico-chemical characteristics (pH, organic matter) in determining ecotoxicity and habitat quality, and draw conclusions for improved floodplain management. Human activities have changed the hydraulics and contaminant fate in river–floodplain ecosystems.
Show more [+] Less [-]Sorption behavior of bensulfuron-methyl on andisols and ultisols volcanic ash-derived soils: Contribution of humic fractions and mineral–organic complexes Full text
2009
Espinoza, Jeannette | Fuentes, Edwar | Báez, Maria E.
Bensulfuron-methyl sorption was studied in Andisol and Ultisol soils in view of their characteristic physical and chemical properties, presenting acidic pH and variable charge. Humic and fulvic acids (HA and FA) and humin (HUM) contributions were established. Sorption was studied by using two synthetic sorbents, an aluminum-silicate with iron oxide coverage and the same sorbent coated with humic acid. Freundlich model described Bensulfuron-methyl behavior in all sorbents (R2 0.969–0.998). Kf for soils (8.3–20.7 μg1−1/n mL1/n g−1) were higher than those reported in the literature. Organic matter, halloysite or kaolinite, and specific surface area contributed to the global process. The highest Kf for HA, FA and HUM were 539.5, 82.9, and 98.7 μg1−1/n mL1/n g−1. Model sorbents described the participation of variable charge materials with high adsorption capacity. The constant capacitance model was used to assess effects of Bensulfuron-methyl adsorption on the distribution of SOH, SOH2+ and SO− sites of sorbents. Organic matter, phyllosilicates, variable charge minerals and organo-mineral complexes contribute to bensulfuron-methyl sorption on volcanic ash-derived soils.
Show more [+] Less [-]Identification of Chinese cabbage genotypes with low cadmium accumulation for food safety Full text
2009
Liu, Weitao | Zhou, Qixing | Sun, Yuebing | Liu, Rui
The pot-culture experiment and field studies were conducted to screen out and identify cadmium (Cd) excluders from 40 Chinese cabbage genotypes for food safety. The results of the pot-culture experiment indicated that the shoot Cd concentrations under three treatments (1.0, 2.5 and 5.0 mg Cd kg⁻¹ Soil) varied significantly (p < 0.05), with average values of 0.70, 3.07 and 5.83 mg kg⁻¹, respectively. The Cd concentrations in 12 cabbage genotypes were lower than 0.50 mg kg⁻¹. The enrichment factors (EFs) and translocation factors (TFs) in 8 cabbage genotypes were lower than 1.0. The field studies further identified Lvxing 70 as a Cd-excluder genotype (CEG), which is suitable to be planted in low Cd-contaminated soils (Cd concentration should be lower than 1.25 mg kg⁻¹) for food safety. Lvxing 70 was identified as a Cd-excluder genotype (CEG) and suitable to be cultivated in low Cd-contaminated soils for food safety.
Show more [+] Less [-]POP bioaccumulation in macroinvertebrates of alpine freshwater systems Full text
2009
Bizzotto, E.C. | Villa, S. | Vighi, M.
This study serves to investigate the uptake of POPs in the different trophic levels (scrapers, collectors, predators, shredders) of macroinvertebrate communities sampled from a glacial and a non-glacial stream in the Italian Alps. The presented results show that the contaminant concentrations in glacial communities are generally higher compared to those from non-glacial catchments, highlighting the importance of glaciers as temporary sinks of atmospherically transported pollutants. Moreover, the data also suggests that in mountain systems snow plays an important role in influencing macroinvertebrate contamination. The main chemical uptake process to the macroinvertebrates is considered to be bioconcentration from water, as similar contaminant profiles were observed between the different trophic levels. The role of biomagnification/bioaccumulation is thought to be absent or negligible. The enrichment of chemicals observed in the predators is likely to be related to their greater lipid content compared to that of other feeding groups. Influence of POP release in glacial-fed streams, enhanced by global warming, on pristine aquatic ecosystems.
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