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VOC in an urban and industrial harbor on the French North Sea coast during two contrasted meteorological situations
2009
Roukos, Joelle | Riffault, Véronique | Locoge, Nadine | Plaisance, Hervé
Two measurement campaigns of volatile organic compounds (VOC) were carried out in the industrial city of Dunkerque, using Radiello passive samplers during winter (16-23 January) and summer (6-13 June) 2007. 174 compounds were identified belonging to six chemical families. Classifying sampling sites with similar chemical profiles by hierarchical ascending classification resulted in 4 groups that reflected the influence of the main industrial and urban sources of pollution. Also, the BTEX (Benzene, Toluene, Ethylbenzene and Xylenes) quantification allowed us to map their levels of concentration. Benzene and toluene (BT) showed high concentrations in Northern Dunkerque reflecting the influence of two industrial plants. Differences among spatial distributions of the BT concentrations over contrasted meteorological conditions were also observed. An atypical ratio of T/B in the summer samples led us to investigate the BTEX origins shedding light on the contribution of pollutants transported across various zones of VOC emissions situated in Europe. This study was devoted for screening of VOC and investigation of local and regional source contributions to BTEX concentration in a French industrialized harbor.
Mostrar más [+] Menos [-]Biomonitors and the assessment of ecological impacts: Distribution of herbivorous epifauna in contaminated macroalgal beds
2008
Roberts, David A. | Johnston, Emma L. | Poore, Alistair G.B.
We determined metal contents of co-occurring algae Padina crassa and Sargassum sp. in Port Jackson (Australia), and relationships between metal levels and the abundance of epifaunal amphipods. Copper, lead and zinc concentrations were amongst the highest yet recorded in these algae. Copper, manganese and lead concentrations were far greater in P. crassa than Sargassum sp., possibly due to the low growth of P. crassa in proximity to contaminated sediments. However, in manipulative experiments the proximity of algae to sediments did not explain these differences. The abundance of herbivorous amphipods correlated negatively with the copper content of P. crassa, but not with the lower concentrations in Sargassum sp. The greater contamination of P. crassa led to patchy distributions of metals in algal beds and recolonisation experiments showed Sargassum sp. acts as a refuge from contaminants for epifauna. The contamination of macroalgae may pose threats to epifauna in harbours around the world. The accumulation of metals by macroalgae may pose ecological threats to herbivorous epifauna in ports and harbours worldwide.
Mostrar más [+] Menos [-]Use of the sea hare (Aplysia fasciata) in marine pollution biomonitoring of harbors and bays
2018
Dirrigl, Frank J. | Badaoui, Zachariah | Támez, Carlos | Vitek, Christopher J. | Parsons, Jason G.
Our study evaluated heavy metal concentrations in soft tissues of sea hare, Aplysia fasciata, from the Lower Laguna Madre, Texas. Heavy metals in tissues followed Se>As>Pb>Cd. Concentrations ranged As (BDL-28.08), Cd (BDL-5.50), Pb (BDL-12.85) and Se (4.25–93.43ppm). Median As, Cd, Pb, and Se tissue levels exceeded exposure levels. Significant relationships occurred in metal-metal (AsCd, AsPb, CdPb, CdSe, and PbSe), metal-tissue (significant Se uptake by inhalant and exhalant siphons and As in the hepatopancreas), and metal-metal within tissue (AsPb in the hepatopancreas and CdPb in the digestive cecum) analyses (p<0.05). Bioaccumulation factors (BAF) suggested the inhalant siphon, hepatopancreas, and digestive cecum function as macroconcentrators of Cd, hepatopancreas and digestive cecum as macroconcentrators of Pb, and all tissues were deconcentrators for As and Se. As a bioaccumulator of heavy metals, Aplysia was evaluated as a bioindicator of marine pollution in harbors and bays.
Mostrar más [+] Menos [-]Distribution, inventory and turnover of benthic organic biomass in the Strait of Georgia, Canada, in relation to natural and anthropogenic inputs
2014
Burd, Brenda J.
Recently compiled databases facilitated estimation of basin-wide benthic organic biomass and turnover in the Strait of Georgia, an inland sea off western Canada. Basin-wide organic biomass was estimated at 43.1×106kgC and production was 54.6×106kgCyr−1, resulting in organic biomass turnover (P/B) of 1.27×yr−1. Organic biomass and production for sub-regions were predictable from modified organic flux (r2>0.9). P/B declined significantly with increasing modified organic flux, suggesting greater biomass storage in high flux sediments. Biomass and production were highest, and P/B lowest near the Fraser River. Annual basin-wide benthic production was 60% of previously estimated oxidized organic flux to substrates, which agrees with proportional measurements from a recent, localized study.Deviations from expected patterns related to organic enrichment and other stressors are discussed, as are potential impacts to benthic biomass and production, of declining bottom oxygen, increasing bottom temperature and potential changes in riverine input.
Mostrar más [+] Menos [-]Modified, optimized method of determination of Tributyltin (TBT) contamination in coastal water, sediment and biota in Sri Lanka
2021
Bandara, K.R.V. | Chinthaka, S.D.M. | Yasawardene, S.G. | Manage, Pathmalal M.
Tributyltin (TBT) is a toxic organotin compound that belongs to the group of Persistent Organic Pollutants (POPs) and it is documented to cause severe sexual disorders development in aquatic fauna. According to the present study, The TBT concentration in coastal water ranged from 303 ± 7.4 ngL⁻¹ to 25 ± 4.2 ngL⁻¹ wherein sediment was from 107 ± 4.1 ngKg⁻¹ to 17 ± 1.4 ngKg⁻¹. TBT in Perna viridis was found to range from 4 ± 1.2 ngKg⁻¹ to 42 ± 2.2 ngKg⁻¹ wet weight and in ascending order of the body weight. The highest TBT level in water and sediment was found in the Colombo port where the highest level of TBT in P. viridis (42 ± 2.2 ngKg⁻¹) was recorded from the Dikkowita fishery harbor. A positive correlation between the number of male P. viridis and TBT level (p < 0.05) suggests possible reproductive impairment in aquatic animals exposed continuously to a high concentration of TBT.
Mostrar más [+] Menos [-]Are environmental risk estimations linked to the actual environmental impact? Application to an oil handling facility (NE Spain)
2017
Valdor, Paloma F. | Puente, Araceli | Gómez, Aina G. | Ondiviela, Bárbara | Juanes, J. A. (José A.)
The environmental risk analysis of aquatic systems includes the evaluation of the likelihood that adverse ecological effects may occur as a result of exposure to one or more stressors. In harbor areas, pollution is provided by a complex mixture of substances with different levels of toxicity, persistence and bioaccumulation, which complicates the hazards characterization and their multiple effects. A study of the relationship between the environmental impact and the environmental risk assessment at a specific isolated oil handling facility was undertaken. The environmental risk of the oil handling facility, considering the consequences of specific pollutants, was estimated and the associated environmental impact was quantified based on a ‘weights of evidence’ approach. The contamination quantified at the potentially affected area around the monobuoy of Tarragona has proved to be related with environmental risk estimations but the lines of evidence obtained do not allow us to assert that the activity developed at this facility has an associated environmental impact.
Mostrar más [+] Menos [-]Phytoremediation and Bio-physical Conditioning of Dredged Marine Sediments for Their Re-use in the Environment
2010
Bianchi, Veronica | Masciandaro, Grazia | Ceccanti, Brunello | Doni, Serena | Iannelli, Renato
A meso-scale pilot plant was set up to test the efficiency of a phytoremediation technique applied to slightly contaminated marine sediments dredged from the port of Livorno (central Italy). The technique applied involved the use of plants (a grass species, Paspalum vaginatum and a shrub species, Tamarix gallica) and earthworms (Eisenia foetida sp.) in order to recreate an active ecosystem in which plants, micro- and macroorganisms could interact with each other through the rhizosphere, for the adsorption, extraction and/or degradation of pollutants. This system enables plants to grow in a fine textured and salt medium highly unsuitable for plant species, and a physical, chemical and biological amelioration of the matrix was observed at the end of the experimentation (after 9 months). The sediment was bio-physically pre-conditioned by mixing it with calcareous material from excavating activities (5:1 v/v) and applying green compost. The presence of microorganisms in the rhizosphere and the earthworms produced a reduction by about 50% of the initial total petroleum hydrocarbon content. The use of a natural chelator with phyto-hormonal properties (humic substances) showed their capability of forming stable complexes, especially with Pb, and their contribution as an agronomic fertiliser. The combined effect of the P. vaginatum and T. gallica in the extraction of heavy metals from the sediment showed promisingly high percentages of metal effectively extracted in comparison with its available fraction (e.g. available Ni = 6.2%; Ni extracted = 15.7%). The technique proposed could be promising for an operational re-use of dredged marine sediments for agricultural purposes, a suitable final destination for the great majority of these contaminated materials from rivers and harbour docks.
Mostrar más [+] Menos [-]Changes of Heavy Metal and PCB Contents in Surficial Sediments of the Barcelona Harbour after the Opening of a New Entrance
2009
Gibert, Oriol | Martínez-Lladó, Xavier | Martí, Vicens | Díez, Sergi | Romo, Javier | Bayona, Josep M. | De Pablo, Joan
The Barcelona harbour is one of the biggest and most important in commercial and passenger traffic in the Mediterranean Sea. In 2003, construction works for the enlargement of the port were carried out with the opening of a new entrance for large boats in the northern area. Following the opening of this new mouth, the redistribution of heavy metals (Hg, Cd, Pb, Cu, Zn, Ni and Cr), As and polychlorinated biphenyls (PCBs) was investigated to discuss their origin and to evaluate the environmental implications. A previous study of the sediments provided a first picture of high levels of heavy metals and PCBs in the innermost harbour (Port Vell). Then, the opening of the northern mouth led to a remarkable decline in the contaminant concentrations and to an improvement of the sediment quality. During the period 2002-2005, the percentage of concentration decreases in Port Vell for Hg, Pb and PCB (from 20% to 34%), for Zn and Cd (from 10% to 15%) and for the remaining metals with values lesser than 10%. This general decline was probably due to a more efficient water flushing between the original and the new northern entrance. Concentrations of target contaminants were also compared against sediment quality guidelines to assess the ecotoxicological significance of sedimentary contaminants on the benthic communities.
Mostrar más [+] Menos [-]Santa Barbara oil spill: short-term analysis of macroplankton and fish
1971
Ebeling, A. W.