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Occurrence of priority pollutants in WWTP effluents and Mediterranean coastal waters of Spain Full text
2011
Martí, N. | Aguado, D. | Segovia-Martínez, L. | Bouzas, A. | Seco, A.
A comprehensive study aimed at evaluating the occurrence, significance of concentrations and spatial distribution of priority pollutants (PPs) along the Comunidad Valenciana coastal waters (Spain) was carried out in order to fulfil the European Water Framework Directive (WFD). Additionally, PP concentrations were also analysed in the effluent of 28 WWTPs distributed along the studied area. In coastal waters 36 organic pollutants of the 71 analysed, including 26 PPs were detected although many of them with low frequency of occurrence. Only 13 compounds, which belong to four different classes (VOCs, organochlorinated pesticides, phthalates and tributyltin compounds (TBT)) showed a frequency of occurrence above 20% in coastal waters. In the results obtained until now, octylphenol, pentachlorobenzene, DEHP and TBT exceeded the annual average concentration (EQS-AAC), and only TBT surpassed the maximum allowable concentration (EQS-MAC). The most frequent contaminants determined in coastal waters were also present in WWTP effluents.
Show more [+] Less [-]Effects of alumina refinery wastewater and signature metal constituents at the upper thermal tolerance of: 1. The tropical diatom Nitzschia closterium Full text
2011
Harford, A.J. | Hogan, A.C. | Tsang, J.J. | Parry, D.L. | Negri, A.P. | Adams, M.S. | Stauber, J.L. | van Dam, R.A.
Ecotoxicological studies, using the tropical marine diatom, Nitzschia closterium (72-h growth rate), were undertaken to assess potential issues relating to the discharge from an alumina refinery in northern Australia. The studies assessed: (i) the species’ upper thermal tolerance; (ii) the effects of three signature metals, aluminium (Al), vanadium (V) and gallium (Ga) (at 32°C); and (iii) the effects of wastewater (at 27 and 32°C). The critical thermal maximum and median inhibition temperature for N. closterium were 32.7°C and 33.1°C, respectively. Single metal toxicity tests found that N. closterium was more sensitive to Al compared to Ga and V, with IC₅₀s (95% confidence limits) of 190 (140–280), 19,640 (11,600–25,200) and 42,000 (32,770–56,000)μgL⁻¹, respectively. The undiluted wastewater samples were of low toxicity to N. closterium (IC₅₀s>100% wastewater). Environmental chemistry data suggested that the key metals and discharge are a very low risk to this species.
Show more [+] Less [-]Distribution and characteristics of PAHs in sediments from the Mediterranean coastal environment of Egypt Full text
2011
Barakat, Assem O. | Mostafa, Alaa | Wade, Terry L. | Sweet, Stephen T. | El Sayed, Nadia B.
To assess the contamination of polycyclic aromatic hydrocarbons (PAHs) in the Mediterranean coastal environment of Egypt, 26 sediment samples from the coastline, harbours, estuaries and coastal lakes were collected and analyzed. The sediment PAH concentrations of thirty-nine 2–6 ring PAHs ranged from 13.5 to 22,600ng/g. PAH profiles varied according to the nature of the site and its proximity to sources. Industrialized and urbanized region showed high level of PAHs contamination. In general, the contamination levels of PAHs were similar to those observed in contaminated and slightly contaminated sediments of the Mediterranean Sea. Molecular indices based on ratios of selected PAH concentrations were used to differentiate PAHs from pyrogenic and petrogenic and mixed origins. Good correlations were observed between the petrogenic index, MP/P, A-PAHs/P-PAHs and HMW/LMW. Finally, PAH levels in sediments were compared with Sediments Quality Guidelines (ERM–ERL) for evaluation of probable toxic effects on organism.
Show more [+] Less [-]Organic and inorganic matter in Louisiana coastal waters: Vermilion, Atchafalaya, Terrebonne, Barataria, and Mississippi regions Full text
2011
Schaeffer, Blake A. | Conmy, Robyn N. | Aukamp, Jessica | Craven, George | Ferer, Erin J.
Chromophoric dissolved organic matter (CDOM) spectral absorption, dissolved organic carbon (DOC) concentration, and the particulate fraction of inorganic (PIM) and organic matter (POM) were measured in Louisiana coastal waters at Vermilion, Atchafalaya, Terrebonne, Barataria, and Mississippi River locations, in 2007–2008. The range of CDOM was 0.092m⁻¹ at Barataria in June 2008 to 11.225m⁻¹ at Mississippi in February 2008. An indicator of organic matter quality was predicted by the spectral slope of absorption coefficients from 350 to 412nm which was between 0.0087m⁻¹ at Mississippi in May 2008 and 0.0261m⁻¹ at Barataria in June 2008. CDOM was the dominant component of light attenuation at Terrebonne and Barataria. Detritus and CDOM were the primary components of light attenuation at Vermilion, Atchafalaya, and Mississippi. DOC ranged between 65 and 1235μM. PIM ranged between 1.1 and 426.3mgL⁻¹ and POM was between 0.3 and 49.6mgL⁻¹.
Show more [+] Less [-]Occurrence of polycyclic aromatic hydrocarbons (PAHs) in seawater from the Western Taiwan Strait, China Full text
2011
Wu, Yu-Ling | Wang, Xin-Hong | Li, Yong-Yu | Hong, Hua-Sheng
Seawater samples (including surface water and bottom water) were collected from the Western Taiwan Strait (WTS) during June 24–25, 2009; polycyclic aromatic hydrocarbons (PAHs) in dissolved phase and particulate phase were analyzed, respectively. The results showed that the total concentrations of PAHs in the dissolved phase and particulate phase were ranged from 12.3 to 58.0ngL⁻¹, and 10.3–45.5ngL⁻¹, which showed a low-middle contamination level in the China Seas. The spatial variability of PAHs may be related to the complicated currents of WTS, especially the Min-Zhe coastal current. PAHs diagnostic ratios suggested that PAHs mainly originated from the inputs of pyrolytic (combustion) sources, which might be contributed to land-based atmospheric deposition. The particle-water partition coefficients of individual PAH showed that partitions were not correlated with suspended particulate matter content, dissolved organic carbon or salinity, similar to the Yangtze coastal area.
Show more [+] Less [-]Electrochemical disinfection for ballast water management: Technology development and risk assessment Full text
2011
Nanayakkara, K.G Nadeeshani | Zheng, Yu-Ming | Alam, A.K.M Khorshed | Zou, Shuaiwen | Chen, J Paul
Ballast water is essential in maintaining the balance and structural integrity of ships during voyage. However, it has created biological invasion threats to the ocean environment. An innovative electrochemical technology was developed in this study. The microorganisms regulated by the International Maritime Organization (D2) were used as the target organisms. It was found that the required energy to meet the D2 was below 0.006kWh/m³. The size of disinfector (m³) was about 0.5% of treatment flow rate (m³/h). The complete disappearance of chlorine in seawater was achieved after three days. The ballast tank corrosion was not worsened due to the application of technology. The ecotoxicity studies showed no toxic effect on fish, invertebrate, and algae. Finally, the environmental risk assessment showed the treated water did not pose threats to the environment. It can therefore be concluded that the technology provides a cost-effective and environmental friendly solution to ballast water management.
Show more [+] Less [-]Sampling epifauna, a necessity for a better assessment of benthic ecosystem functioning: An example of the epibenthic aggregated species Ophiothrix fragilis from the Bay of Seine Full text
2011
Lozach, Sophie | Dauvin, Jean-Claude | Méar, Yann | Murat, Anne | Davoult, Dominique | Migné, Aline
Sampling the sea bottom surface remains difficult because of the surface hydraulic shock due to water flowing through the gear (i.e., the bow wave effect) and the loss of epifauna organisms due to the gear’s closing mechanism. Slow-moving mobile epifauna, such as the ophiuroid Ophiothrix fragilis, form high-density patches in the English Channel, not only on pebbles like in the Dover Strait or offshore Brittany but also on gravel in the Bay of Seine (>5000indm⁻²). Such populations form high biomasses and control the water transfer from the water column to the sediment. Estimating their real density and biomass is essential for the assessment of benthic ecosystem functioning using trophic web modelling. In this paper, we present and discuss the patch patterns and sampling efficiency of the different methods for collecting in the dense beds of O. fragilis in the Bay of Seine. The large Hamon grab (0.25m⁻²) highly under-estimated the ophiuroid density, while the Smith McIntyre appeared adequate among the tested sampling grabs. Nowadays, diving sampling, underwater photography and videos with remote operated vehicle appear to be the recommended alternatives to estimate the real density of such dense slow-moving mobile epifauna.
Show more [+] Less [-]Characterization of marine debris in North Carolina salt marshes Full text
2011
Viehman, Shay | Vander Pluym, Jenny L. | Schellinger, Jennifer
Marine debris composition, density, abundance, and accumulation were evaluated in salt marshes in Carteret County, North Carolina seasonally between 2007 and 2009. We assessed relationships between human use patterns and debris type. Wave effects on marine debris density were examined using a GIS-based forecasting tool. We assessed the influence of site wave exposure, period, and height on debris quantity. Presence and abundance of debris were related to wave exposure, vegetation type and proximity of the strata to human population and human use patterns. Plastic pieces accounted for the majority of all debris. Small debris (0–5cm) was primarily composed of foam pieces and was frequently affiliated with natural wrack. Large debris (>100cm) was encountered in all marsh habitat types surveyed and was primarily composed of anthropogenic wood and derelict fishing gear. Marsh cleanup efforts should be targeted to specific habitat types or debris types to minimize further damage to sensitive habitats.
Show more [+] Less [-]Monitoring the effects of disposal of fine sediments from maintenance dredging on suspended particulate matter concentration in the Belgian nearshore area (southern North Sea) Full text
2011
Fettweis, Michael | Baeye, Matthias | Francken, Frederic | Lauwaert, Brigitte | Van den Eynde, Dries | Van Lancker, Vera | Martens, Chantal | Michielsen, Tinne
The impact of continuous disposal of fine-grained sediments from maintenance dredging works on the suspended particulate matter concentration in a shallow nearshore turbidity maximum was investigated during dredging experiment (port of Zeebrugge, southern North Sea). Before, during and after the experiment monitoring of SPM concentration using OBS and ADV altimetry was carried out at a location 5km west of the disposal site. A statistical analysis, based on the concept of populations and sub-sampling, was applied to evaluate the effect. The data revealed that the SPM concentration near the bed was on average more than two times higher during the dredging experiment. The disposed material was mainly transported in the benthic layer and resulted in a long-term increase of SPM concentration and formation of fluid mud layers. The study shows that SPM concentration can be used as an indicator of environmental changes if representative time series are available.
Show more [+] Less [-]Polybrominated diphenyl ethers and their hydroxylated/methoxylated analogs: Environmental sources, metabolic relationships, and relative toxicities Full text
2011
Wiseman, Steve B. | Wan, Yi | Chang, Hong | Zhang, Xiaowei | Hecker, Markus | Jones, Paul D. | Giesy, John P.
Brominated compounds are ubiquitous in the aquatic environment. The polybrominated diphenyl ether (PBDE) flame retardants are anthropogenic compounds of concern. Studies suggest that PBDEs can be biotransformed to hydroxylated brominated diphenyl ethers (OH-BDE). However, the rate of OH-BDE formation observed has been extremely small. OH-BDEs have also been identified as natural compounds produced by some marine invertebrates. Another class of compounds, the methoxylated BDEs (MeO-BDEs), has also been identified as natural compounds in the marine environment. Both the OH-BDEs and MeO-BDEs bioaccumulate in higher marine organisms. Recent studies have demonstrated that MeO-BDEs can be biotransformed to OH-BDEs and this generates greater amounts of OH-BDEs than could be generated from PBDEs. Consequently, MeO-BDEs likely represent the primary source of metabolically derived OH-BDEs. Given that for some endpoints OH-BDEs often exhibit greater toxicity compared to PBDEs, it is prudent to consider OH-BDEs as chemicals of concern, despite their seemingly “natural” origins.
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