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Organochlorine pesticides and polychlorinated biphenyls in the Bering flounder (Hippoglossoides robustus) from the Sea of Okhotsk
2018
Lukyanova, Olga N. | Tsygankov, Vasiliy Yu | Boyarova, Margarita D.
The purpose of this study is to establish the presence of POPs in the Bering flounder (Hippoglossoides robustus) from the Sea of Okhotsk (North-West Pacific). Concentration of OCPs (α-HCH, β-HCH, γ-HCH, o,p′-DDT, p,p′-DDT, o,p′-DDD, p,p′-DDD, o,p′-DDE and p,p′-DDE) and PCBs (28, 52, 155, 101, 118, 143, 153, 138, 180, 207) in samples were measured by GC–MS and GC–ECD. The mean OCP concentrations in flounder from East and South areas of the Sea of Okhotsk were 99.8 ± 125.4 and 53.6 ± 40.5 ng/g lipid, respectively; PCB congeners – 112 ± 94.2 and 88.8 ± 50.8 ng/g lipid, respectively. POPs in fish tissue decreased in the order: PCBs > HCHs > DDTs. Our results indicate that consumers will have no health risk due to fish consumption from Sea of Okhotsk. OCP and PCB levels in the Sea of Okhotsk may be considered as background level for the North Pacific.
Show more [+] Less [-]Nutrients in Urban Stormwater Runoff: Current State of the Science and Potential Mitigation Options
2018
Yang, Yun-Ya | Lusk, MaryG.
PURPOSE OF REVIEW: Stormwater runoff of nutrients from developed landscapes is recognized as a major threat to water quality degradation through cultural eutrophication, which can lead to ecosystem imbalances and harmful algal growth. This review summarizes the current state-of-knowledge on the occurrence, sources, and transport processes of nitrogen (N) and phosphorus (P) in urban stormwater runoff and describes strategies for nutrient management of urban stormwater runoff. Future research needs identified from this review are provided as well. RECENT FINDINGS: Stormwater runoff of nutrients from urban environments to fresh water is controlled by multiple factors, including type of inputs, land use, development patterns, and management strategies. Recent research on stormwater management strategies has focused on internal nutrient cycling processes, such as microbial transformations of N in conventional wet ponds or bioretention cells, leading to a better understanding of the mechanisms that control the efficacy of stormwater management practices. Mitigating nutrient exports from urban environments will require controlling both quantities and sources of nutrient inputs into water systems, as well as new mechanistic understanding of the biogeochemical processes controlling nutrient treatment in stormwater ponds and low impact design (LID) structures. We need more research on source tracking of P from stormwater runoff as information is still relatively scarce. There is also a need to obtain better understanding of the dynamic interactions among multiple factors (e.g., sources, land use, characteristic of catchment and climate, management strategies) that control fate and transport of nutrients in urban stormwater runoff.
Show more [+] Less [-]Trophic transfer of cadmium in marine food webs from Western Chilean Patagonia and Antarctica
2018
Espejo, Winfred | Padilha, Janeide de A. | Kidd, Karen A. | Dorneles, Paulo R. | Barra, Ricardo | Malm, Olaf | Chiang, Gustavo | Celis, José E.
In aquatic environments, Cd contamination is a great concern because this non-essential metal presents risks both for wildlife and human health. Data about the concentration and transfer of Cd in Patagonian and Antarctic aquatic food webs are crucial for assessing the impacts of this element in pristine ecosystems. Consequently, the concentration of Cd was measured in thirty-two species collected in the 2014 austral summer from two locations of the Western Patagonia and two locations of the Antarctic Peninsula. The main objective of this work was to assess the relationship between Cd concentration and trophic level determined by δ15N. In the studied trophic positions, Cd showed a positive relationship between concentration and trophic level, which suggests biomagnification of this element in macroinvertebrates. However, there was a significant dilution when higher trophic organisms were considered.
Show more [+] Less [-]Contamination level, chemical fraction and ecological risk of heavy metals in sediments from Daya Bay, South China Sea
2018
Liu, Jin-Jun | Ni, Zhi-Xin | Diao, Zeng-Hui | Hu, Yong-Xia | Xu, Xiang-Rong
Contamination level, chemical fraction and ecological risk of heavy metals in sediments from Daya Bay (DYB) were conducted in this study. The results revealed that the concentration of Cr, Cu, Zn, As, Cd and Pb in sediments were in the range of 36.38–90.33, 9.54–61.32, 33.54–207.33, 7.80–18.43, 0.13–0.43 and 15.89–30.01 mg kg−1, respectively, with bioavailable fractions of 13.29, 54.16, 47.60, 32.74, 68.14, 26.59%, respectively. A modified potential ecological risk index (MRI) was used for the ecological risk assessment, with ecological risk contribution ratios of 75.73, 14.29, 5.47, 1.74, 1.57 and 1.21% for Cd, As, Cu, Cr, Pb and Zn, respectively. The main contaminants were Cd and As, with their ecological risks “High” and “Moderate” levels, and their enrichment degrees “Moderately Severe” and “Moderate”, respectively. The multivariate statistical analysis suggested that the various anthropogenic activities along the bay might contribute mainly to the heavy metals contamination in DYB.
Show more [+] Less [-]Organochlorine pesticide accumulation in seabirds and marine mammals from the Northwest Pacific
2018
Tsygankov, Vasiliy Yu | Lukyanova, Olga N. | Boyarova, Margarita D.
Bioaccumulation of organochlorine pesticides by marine organisms is one of the methods of environmental quality. Concentrations of organochlorine pesticides (HCH isomers (α-, β-, γ-HCH), p,p′-DDT and its metabolites (p,p′-DDD, p,p′-DDE)) in samples of seabirds (Northern fulmar Fulmarus glacialis, Crested auklet Aethia cristatella, Auklet-crumb Aethia pusilla, Pacific gull Larus schistisagus, and Gray petrel Oceanodroma furcate) and marine mammals (Gray whales Eschrichtius robustus and Pacific walrus Odobenus rosmarus divergens) were measured by a GC–MS. The total concentration of OCPs in mammals was higher than in seabirds. Environmental biomonitoring with the use of seabirds and marine mammals, as a long-lived species, is used for global monitoring, since bioaccumulation in these organisms occurs throughout life. The environmental assessment of the Northwest Pacific marine ecosystems revealed that the levels of OCP contamination in this area are similar to the other subarctic regions of the World Ocean.
Show more [+] Less [-]Comparative Risk Assessment of spill response options for a deepwater oil well blowout: Part 1. Oil spill modeling
2018
French-McCay, Deborah | Crowley, Deborah | Rowe, Jill J. | Bock, Michael | Robinson, Hilary | Wenning, Richard | Walker, Ann Hayward | Joeckel, John | Nedwed, Tim J. | Parkerton, Thomas F.
Oil spill model simulations of a deepwater blowout in the Gulf of Mexico De Soto Canyon, assuming no intervention and various response options (i.e., subsea dispersant injection SSDI, in addition to mechanical recovery, in-situ burning, and surface dispersant application) were compared. Predicted oil fate, amount and area of surfaced oil, and exposure concentrations in the water column above potential effects thresholds were used as inputs to a Comparative Risk Assessment to identify response strategies that minimize long-term impacts. SSDI reduced human and wildlife exposure to volatile organic compounds; dispersed oil into a large water volume at depth; enhanced biodegradation; and reduced surface water, nearshore and shoreline exposure to floating oil and entrained/dissolved oil in the upper water column. Tradeoffs included increased oil exposures at depth. However, since organisms are less abundant below 200 m, results indicate that overall exposure of valued ecosystem components was minimized by use of SSDI.
Show more [+] Less [-]Seasonal variations and environmental risk assessment of trace elements in the sediments of Uppanar River estuary, southern India
2018
Gopal, V. | Nithya, B. | Magesh, N.S. | Jayaprakash, M.
Twenty four surface sediments were gathered from the Uppanar river estuary, southern India to evaluate the trace element contamination risk in the sediments. The circulation of organic matter and calcium carbonate were controlled by algal blooms and shell fragments. Moreover, the concentrations of iron and manganese in the estuarine sediments were possibly contributed by riverine sources and geogenic processes. The geoaccumulation index, enrichment factor and contamination factor reveals that the sediments were contaminated by copper and chromium. The pollution load index recommends that the estuarine sediments have the risk of pollution. The sediment pollution index highlights that the majority of the sediments are low polluted sediments. The potential ecological risk index discloses that the Uppanar river estuary is under moderate risk. The statistical analysis reveals that the organic matter content is managed by fine fractions and the majority of the trace elements are associated with each other having similar origin.
Show more [+] Less [-]Oxidative conversion of potential perfluoroalkyl acid precursors in Jiaozhou Bay and nearby rivers and sewage treatment plant effluent in China
2018
Wang, Shiliang | Cao, Xuezhi | Zhang, Hui | Yang, Yuewei | Zhang, Min
Precursors that can be transformed into perfluoroalkyl acids (PFAAs) have not been investigated in detail. In this study, the levels of potential PFAA precursors in the Jiaozhou Bay, inflowing rivers, and STP (sewage treatment plant) effluents were investigated by converting all PFAA precursors into perfluorinated carboxylic acids (PFCAs) by chemical oxidation. The significance of controlling PFAA precursors was indicated by the ratios of PFCAs converted by the oxidative treatment of precursors to PFAAs before oxidation (∑△[PFCAC4-C12]/∑[PFAA]before oxidation). The higher levels of △[PFCAC4-C12] (average = 18.89 ng/L) and lower ratios (∑△[PFCAC4-C12]/∑[PFAA]before oxidation, average = 0.21) were revealed in the STP effluents rather than in the water of the Jiaozhou Bay and rivers, which implied the precursors conversion during the sewage treatment process. The concentrations of △[PFCAs] and the aforementioned ratios showed apparent spatial and temporal differences. These results indicated that STPs were the important sources of precursors to other water bodies.
Show more [+] Less [-]Short-term cadmium exposure induces gas exchanges, morphological and ultrastructural disturbances in mangrove Avicennia schaueriana young plants
2018
Garcia, Janaina S. | Dalmolin, Ândrea C. | Cortez, Priscila A. | Barbeira, Paulo S. | Mangabeira, Pedro A.O. | França, Marcel G.C.
Mangroves have been subject to more metal contamination, including cadmium (Cd). This study evaluated if a relatively short Cd exposure may induce metabolic, morphological and ultrastructural cell disturbance in Avicennia schaueriana. Cd induced evident constraints to seedlings since there was reduction in leaf gas exchanges and the plants did not survive for more than 10 days at a higher Cd exposure in controlled conditions. The highest Cd accumulation was observed in roots and gradually less in stem and leaves. Cadmium induced lignin deposition was observed in xylem cells of all vegetative organs. Intense sclerification in xylem cells, endoderm and change in the hypoderm organization were also detected. Cadmium clearly induced chloroplast deformities with ruptures of its membranes, thylakoids and core and provoked cytoplasm disorganization. These metal constraints under natural conditions for long term can lead to the accumulation of cellular and metabolic damages and jeopardize seedlings establishment and local biodiversity.
Show more [+] Less [-]Untargeted approach for the evaluation of anthropic impact on the sheltered marine area of Portofino (Italy)
2018
Di Carro, Marina | Magi, Emanuele | Massa, Francesco | Castellano, Michela | Mirasole, Cristiana | Tanwar, Shivani | Olivari, Enrico | Povero, Paolo
Seawater passive sampling with Polar Organic Chemical Integrative Samplers (POCIS) combined with Gaschromatography-Mass Spectrometry analysis were employed as a tool for screening unknown contaminants in a complex Ligurian marine coastal area.The untargeted approach allowed recognizing different classes of compounds, mainly hydrocarbons from C20 to C30. Besides, two chemicals, deriving from anthropic activities, N-butylbenzenesulfonamide (NBBS) and diphenyl sulfone (DPS), were identified and quantified in all samples. Both analytes showed decreasing concentrations from the more confined site to the outer one. The oceanographic characterization of the area performed with multiparametric probes provided useful information, in agreement with chemical analyses. The presence of NBBS and DPS in the site presenting lower continental inputs demonstrated the usefulness of the integrative sampling approach for temporal and spatial monitoring, especially for low level and/or short-term pollution events that traditional monitoring can fail to detect.
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