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Polycyclic aromatic and aliphatic hydrocarbons pollution at the coast of Aliağa (Turkey) ship recycling zone Texto completo
2012
Neşer, Gökdeniz | Kontas, Aynur | Ünsalan, Deniz | Altay, Oya | Darılmaz, Enis | Uluturhan, Esin | Küçüksezgin, Filiz | Tekoğul, Nermin | Yercan, Funda
Aliağa Bay is one of the most important maritime zones of Turkey where shipping activity, shipbreaking industry, steel works and petrochemical complexes exist together. Polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons in sediment of the Aliağa Bay were investigated to evaluate an environmental risk assessment from PAHs contamination in 2009–2010. Aliphatic and PAHs diagnostic ratios were showed to be mainly petroleum-originated and pyrolitic contaminations, respectively. The TEL/PEL analysis suggests that Aliağa sediments were likely to be contaminated by acutely toxic PAH compounds.
Mostrar más [+] Menos [-]Massive sedimentation of fine sediment with organic matter and enhanced benthic–pelagic coupling by an artificial dyke in semi-enclosed Chonsu Bay, Korea Texto completo
2012
Lee, Jae-seong | Kim, Kee Hyun | Shim, JungHee | Han, Jeong Hee | Choi, Yang Ho | Khang, Bhum-Joo
To assess the impact of an artificial dyke in Chonsu Bay (CBD) on the organic carbon (Cₒᵣg) cycle, we measured excess ²¹⁰Pb activities, Cₒᵣg and nitrogen content in sediment cores. The Cₒᵣg oxidation rates (Cₒₓ) on the surface sediment and benthic nutrient fluxes were also quantified with an in situ benthic chamber. The higher excess ²¹⁰Pb inventory, Cₒᵣg and nitrogen in cores near the CBD indicated lateral transport and local, massive deposition of particulate matter due to tidal circulation altered by artificial dyke construction. The Cₒₓ in sediment near the CBD was about twice as high as that out of the bay, suggesting the importance of benthic remineralization of organic matter. The benthic fluxes of dissolved inorganic nitrogen and phosphate were four to six times higher than those outside the bay, corresponding to 141% and 131% respectively, of the requirements for primary production.
Mostrar más [+] Menos [-]Assessing the additive risks of PSII herbicide exposure to the Great Barrier Reef Texto completo
2012
Lewis, Stephen E. | Schaffelke, Britta | Shaw, Melanie | Bainbridge, Zoë T. | Rohde, Ken W. | Kennedy, Karen | Davis, Aaron M. | Masters, Bronwyn L. | Devlin, Michelle J. | Mueller, Jochen F. | Brodie, J. E. (Jon E.)
Herbicide residues have been measured in the Great Barrier Reef lagoon at concentrations which have the potential to harm marine plant communities. Monitoring on the Great Barrier Reef lagoon following wet season discharge show that 80% of the time when herbicides are detected, more than one are present. These herbicides have been shown to act in an additive manner with regards to photosystem-II inhibition. In this study, the area of the Great Barrier Reef considered to be at risk from herbicides is compared when exposures are considered for each herbicide individually and also for herbicide mixtures. Two normalisation indices for herbicide mixtures were calculated based on current guidelines and PSII inhibition thresholds. The results show that the area of risk for most regions is greatly increased under the proposed additive PSII inhibition threshold and that the resilience of this important ecosystem could be reduced by exposure to these herbicides.
Mostrar más [+] Menos [-]Monitoring temporal and spatial trends of legacy and emerging contaminants in marine environment: Results from the environmental specimen bank (es-BANK) of Ehime University, Japan Texto completo
2012
Tanabe, Shinsuke | Ramu, Karri
The Environmental Specimen Bank (es-BANK) for Global Monitoring at the Center for Marine Environmental Studies, Ehime University, Japan has more than four decades of practical experience in specimen banking. Over the years, es-BANK has archived specimens representing a wide range of environmental matrices, i.e. fishes, reptiles, birds, aquatic mammals, terrestrial mammals, human, soils, and sediments. The samples have been collected as part of the various monitoring programs conducted worldwide. The current review is a summary of selected studies conducted at the Center for Marine Environmental Studies, on temporal and spatial trends of legacy and emerging contaminants in the marine environment. One of the major conclusions drawn from the studies is that environmental problems are no more regional issues and, thus, environmental specimen banking should not be limited to national boundaries, but should have a global outlook.
Mostrar más [+] Menos [-]Pollutant impacts to Cape Hatteras National Seashore from urban runoff and septic leachate Texto completo
2012
Mallin, Michael A. | McIver, Matthew R.
The sandy barrier islands of Cape Hatteras National Seashore, USA, attract large seasonal influxes of tourists, and are host to numerous motels, rentals and second homes. To investigate the impacts of nearby urbanization on public trust waters, sampling was conducted in nine brackish water bodies within this coastal national park. A large tidal urban ditch delivered runoff-driven fecal-contaminated water directly into public beach waters. At all sites except the control, ammonium, phosphorus and fecal bacteria concentrations were high, strongly seasonal and significantly correlated with community water usage, indicating that increased septic tank usage led to increased pollutant concentrations in area waterways. Nutrients from septic systems caused ecosystem-level problems from algal blooms, BOD, and hypoxia while fecal microbes created potential human health problems. Septic system usage is widespread in sensitive coastal areas with high water tables and sandy soils and alternatives to standard septic systems must be required to protect human health and the environment.
Mostrar más [+] Menos [-]Contaminant concentrations, biochemical and hematological biomarkers in blood of West Indian manatees Trichechus manatus from Brazil Texto completo
2012
Anzolin, D.G. | Sarkis, J.E.S. | Díaz, E. | Soares, D.G. | Serrano, I.L. | Borges, J.C.G. | Souto, A.S. | Taniguchi, S. | Montone, R.C. | Bainy, A.C.D. | Carvalho, P.S.M.
The West Indian manatee Trichechus manatus is threatened with extinction in Brazil, and this study focused on nondestructive blood samples analyzed for metals, polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), as well as biochemical and hematological biomarkers. Studied manatees were kept at Projeto Peixe-Boi headquarters in Pernambuco State, and at two natural areas in estuaries where they are released to the wild. Manatees kept at the natural estuary in Paraiba State have blood concentrations of Al, Pb, Cd, Sn that are 11, 7, 8 and 23 times greater, respectively, than the concentrations found in blood of animals from the same species in Florida, USA. An inhibition of butyrylcholinesterase in manatees kept at the two reintroduction sites in Alagoas and Paraiba States indicated possible exposure of the animals to cholinesterase inhibitor insecticides. PCBs and OCPs were not detected. Results from this study will help delineate conservation efforts in the region.
Mostrar más [+] Menos [-]Evaluation of bacteriological and nutrient concerns in nearshore waters of a barrier island community in SW Florida Texto completo
2012
Thompson, Mark | Milbrandt, Eric | Bartleson, Richard | Rybak, Alex
To determine if local onsite treatment systems affect nearshore water quality, seasonal and rain event monitoring of bacteria and nitrogen was conducted on the Gulf and estuary sides of Captiva Island. Monitoring wells were used to examine the relationship between surface water and groundwater quality. Nitrates were found to be significantly greater in ground water samples from the areas of Captiva using onsite treatment compared to areas with sewer. However, groundwater enterococci were no greater in areas with onsite treatment. Surface water nitrogen was significantly greater near onsite systems than areas with sewer, linking groundwater and surface water quality. Surface water enterococci increased significantly after rain events. Study results indicated stormwater runoff disperses indicator bacteria from diffuse terrestrial sources into nearshore waters, elevating the concentrations. This study reveals local onsite treatment systems produce elevated surface water nitrogen levels but do not contribute to elevated indicator bacteria concentrations in this system.
Mostrar más [+] Menos [-]Spatial distribution and temporal trends of persistent organochlorine pollutants in sediments from Lake Maryut, Alexandria, Egypt Texto completo
2012
Barakat, Assem O. | Mostafa, Alaa | Wade, Terry L. | Sweet, Stephen T. | El Sayed, Nadia B.
Organochlorine compounds (OCs) in surface and core sediments collected from Lake Maryut, Egypt, were examined to elucidate their distribution, ecological risk and historical trend. To our knowledge, this is the first study on residue levels of OCs in sediments from Lake Maryut. Concentrations of PCBs and DDTs were higher than other OCs, ranging from 3.06 to 388 and from 0.07 to 106ng/g dry wt., respectively. The highest concentrations of OCs were found at stations near the discharge point of sewage and close to industrial areas. The distribution of DDT and its metabolites suggest no recent inputs into the lake environment. Contamination levels of sedimentary PCBs and DDTs, can be categorized moderate to high compared to other urbanized regions worldwide. Temporal trends in OCs levels were influenced by input pathways at two sites. Evaluation of ecotoxicological risks suggests that adverse biological effects are expected mainly in the main basin area.
Mostrar más [+] Menos [-]Algal δ¹⁵N values detect a wastewater effluent plume in nearshore and offshore surface waters and three-dimensionally model the plume across a coral reef on Maui, Hawai‘i, USA Texto completo
2012
Dailer, Meghan L. | Ramey, Hailey L. | Saephan, Stephanie | Smith, Celia M.
The coral reef at Kahekili, Maui is located ∼300m south of the Lahaina Wastewater Reclamation Facility which uses four Class V injection wells to dispose of 3–5million gallons of wastewater effluent daily. Prior research documented that the wastewater effluent percolates into the nearshore region of Kahekili. To determine if the wastewater effluent was detectable in the surface waters offshore, we used algal bioassays from the nearshore region to 100m offshore and throughout the water column from the surface to the benthos. These algal bioassays documented that significantly more wastewater effluent was detected in the surface rather than the benthic waters and allowed us to generate a three-dimensional model of the wastewater plume in the Kahekili coastal region. Samples located over freshwater seeps had the highest δ¹⁵N values (∼30–35‰) and the effluent was detected in surface samples 500m south and 100m offshore of the freshwater seeps (∼8–11‰).
Mostrar más [+] Menos [-]Comparative risk assessment of permethrin, chlorothalonil, and diuron to coastal aquatic species Texto completo
2012
DeLorenzo, Marie E. | Fulton, Michael H.
The precise application of risk assessment can lead to different conclusions about risk depending on how species are grouped in the assessment. We compared the use of different risk assessment methods for three different classes of pesticide, the herbicide diuron, the fungicide chlorothalonil, and the insecticide permethrin for marine and estuarine species. Permethrin was the most toxic pesticide to marine and estuarine crustaceans. Diuron was the most toxic pesticide to algae, and chlorothalonil was most toxic to early life stages of molluscs and other invertebrates. Toxicity data (96h LC50/EC50 values) were analyzed using a probability distribution on the ranked toxicity values and 10th centile values were calculated based on different groups of species and for all species combined. Our results indicate that an assessment of risk based on smaller taxonomic groups can be informative, especially for pesticides of less specific modes of action such as chlorothalonil.
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