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Composition profiles, levels, distributions and ecological risk assessments of trihalomethanes in surface water from a typical estuary of Bohai Bay, China Полный текст
2017
Niu, Zhiguang | Li, Xiaonan | Zhang, Ying
To characterize the spatiotemporal distribution and potential ecological risk for trihalomethanes (THMs) in the surface water of a river estuary, surface water samples were collected over five consecutive months (from March to July 2016) from four sites in the Haihe River estuary of Bohai Bay. The potential ecological risks of THMs were evaluated quantitatively based on a species sensitivity distribution (SSD) model. The results demonstrate that trichloromethane (TCM) was the predominant THM in surface water of the Haihe River estuary (2.93±1.98μg/L) followed by tribromomethane (TBM) (0.42±0.33μg/L), bromodichloromethane (BDCM) (0.14±0.06μg/L) and dibromochloromethane (DBCM) (0.09±0.10μg/L). The concentration of TCM was higher in summer than that in spring, while TBM displayed the opposite trend. The TCM concentration decreased from the estuary to the adjacent sea. However, the levels of TBM and DBCM in the adjacent sea were higher than those in the estuary. The ecological risks of THMs in surface water of Haihe River were notably low, and the ecological risks of THMs in freshwater were generally higher than those in seawater. Compared with other contaminants in water and surface sediment from rivers and coastal areas, the ecological risk levels of THMs in surface water can be considered low. This study is a contribution to the progress of ecological risk assessment of THMs.
Показать больше [+] Меньше [-]Metabolomics of Ulva lactuca Linnaeus (Chlorophyta) exposed to oil fuels: Fourier transform infrared spectroscopy and multivariate analysis as tools for metabolic fingerprint Полный текст
2017
Pilatti, Fernanda Kokowicz | Ramlov, Fernanda | Schmidt, Eder Carlos | Costa, Christopher | Oliveira, Eva Regina de | Bauer, Claudia M. | Rocha, Miguel | Bouzon, Zenilda Laurita | Maraschin, Marcelo
Fossil fuels, e.g. gasoline and diesel oil, account for substantial share of the pollution that affects marine ecosystems. Environmental metabolomics is an emerging field that may help unravel the effect of these xenobiotics on seaweeds and provide methodologies for biomonitoring coastal ecosystems. In the present study, FTIR and multivariate analysis were used to discriminate metabolic profiles of Ulva lactuca after in vitro exposure to diesel oil and gasoline, in combinations of concentrations (0.001%, 0.01%, 0.1%, and 1.0% - v/v) and times of exposure (30min, 1h, 12h, and 24h). PCA and HCA performed on entire mid-infrared spectral window were able to discriminate diesel oil-exposed thalli from the gasoline-exposed ones. HCA performed on spectral window related to the protein absorbance (1700–1500cm−1) enabled the best discrimination between gasoline-exposed samples regarding the time of exposure, and between diesel oil-exposed samples according to the concentration. The results indicate that the combination of FTIR with multivariate analysis is a simple and efficient methodology for metabolic profiling with potential use for biomonitoring strategies.
Показать больше [+] Меньше [-]Enrichment, isolation and biodegradation potential of psychrotolerant polychlorinated-biphenyl degrading bacteria from the Kongsfjorden (Svalbard Islands, High Arctic Norway) Полный текст
2017
Papale, Maria | Giannarelli, Stefania | Francesconi, Sandro | Di Marco, Gaetano | Mikkonen, Anu | Conte, Antonella | Rizzo, Carmen | De Domenico, E. (Emilio) | Michaud, Luigi | Giudice, Angelina Lo
Persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), have been detected in abiotic Arctic matrices: surface sediments and seawater from coastal areas in the Kongsfjorden were collected and analyzed. Levels of PCBs varied depending on the sampling site. Total PCB concentrations were between 11.63 (site C2W) and 27.69pgl−1 (site AW). These levels were comparable to those reported previously in lake sediments from the northern Svalbard.The occurrence and biodegradation potential of cold-adapted PCB-oxidizing bacteria in seawater and sediment along the fjord was also evaluated. After enrichment with biphenyl, 246 isolates were obtained with 45 of them that were able to grow in the presence of the PCB mixture Aroclor 1242, as the sole carbon source. The catabolic gene bphA was harbored by 17 isolates with affiliates to the genera Algoriphagus, Devosia and Salinibacterium that have been never reported as able to utilize PCBs, thus deserving further investigation. The total removal of Aroclor 1242 and selected PCB congeners was evaluated at 4 and 15°C for eight bphA-harboring isolates and Gelidibacter sp. DS-10. With few exceptions, tested strains showed greater efficiency at 15 than at 4°C. Isolates were able to reduce most chromatographic peaks by >50%, with some di- and trichlorobiphenyls that were quite totally removed (>90%).
Показать больше [+] Меньше [-]Mechanistic investigation into sunlight-facilitated photodegradation of pyrene in seawater with oil dispersants Полный текст
2017
Fu, Jie | Gong, Yanyan | Cai, Zhengqing | O'Reilly, S.E. | Zhao, Dongye
This study investigated the effects of 3 model oil dispersants (Corexit EC9500A, Corexit EC9527A and SPC 1000) on photodegradation of pyrene under simulated sunlight. Both Corexit dispersants enhanced photodegradation of pyrene, while SPC1000 slightly inhibited the reaction. Span 80 and Tween 85 were the key ingredients causing the effects, though the underlying mechanisms differed. Span 80 enriches pyrene in the upper layer of water column, whereas Tween 85 induces a photosensitization process. Two reactive oxygen species, 1O2 and O2−, were found responsible for pyrene photodegradation, though the presence of EC9500A suppressed the 1O2 pathway. In terms of photodegradation products, EC9500A enhanced generation of polyaromatic intermediates, i.e., phenaleno[1,9-cd][1,2]dioxine, 1-hydroxypyrene, and 1,8-pyrenequinone, but did not alter the classical photodegradation pathway. The Corexit dispersants were more prone to photochemical decomposition, with multiple by-products detected. The information aids in our understanding of the effects of dispersants on photochemical weathering of oil compositions.
Показать больше [+] Меньше [-]Microplastics effects in Scrobicularia plana Полный текст
2017
Ribeiro, Francisca | Garcia, Ana R. | Pereira, Beatriz P. | Fonseca, María | Mestre, Nélia C. | Fonseca, Tainá G. | Ilharco, Laura M. | Bebianno, Maria João
Microplastics effects in Scrobicularia plana Полный текст
2017
Ribeiro, Francisca | Garcia, Ana R. | Pereira, Beatriz P. | Fonseca, María | Mestre, Nélia C. | Fonseca, Tainá G. | Ilharco, Laura M. | Bebianno, Maria João
One of the most common plastics in the marine environment is polystyrene (PS) that can be broken down to micro sized particles. Marine organisms are vulnerable to the exposure to microplastics. This study assesses the effects of PS microplastics in tissues of the clam Scrobicularia plana. Clams were exposed to 1mgL−1 (20μm) for 14days, followed by 7days of depuration. A qualitative analysis by infrared spectroscopy in diffuse reflectance mode period detected the presence of microplastics in clam tissues upon exposure, which were not eliminated after depuration. The effects of microplastics were assessed by a battery of biomarkers and results revealed that microplastics induce effects on antioxidant capacity, DNA damage, neurotoxicity and oxidative damage. S. plana is a significant target to assess the environmental risk of PS microplastics.
Показать больше [+] Меньше [-]Microplastics effects in Scrobicularia plana Полный текст
2017
Ribeiro, Francisca | Garcia, Ana | Pereira, Beatriz P. | Fonseca, Maria | Mestre, Nélia | Fonseca, Tainá | Ilharco, Laura M. | Bebianno, Maria João
One of the most common plastics in the marine environment is polystyrene (PS) that can be broken down to micro sized particles. Marine organisms are vulnerable to the exposure to microplastics. This study assesses the effects of PS microplastics in tissues of the clam Scrobicularia plana. Clams were exposed to 1mgL-1(20μm) for 14days, followed by 7days of depuration. A qualitative analysis by infrared spectroscopy in diffuse reflectance mode period detected the presence of microplastics in clam tissues upon exposure, which were not eliminated after depuration. The effects of microplastics were assessed by a battery of biomarkers and results revealed that microplastics induce effects on antioxidant capacity, DNA damage, neurotoxicity and oxidative damage. S. plana is a significant target to assess the environmental risk of PS microplastics. | info:eu-repo/semantics/publishedVersion
Показать больше [+] Меньше [-]Physicochemical characterization of Atlantic Canadian seafood processing plant effluent Полный текст
2017
Jamieson, Bryan Lee | Gagnon, Graham A. | Gonçalves, Alex Augusto
The purpose of this study was to conduct a preliminary assessment of the potential impacts of Atlantic Canadian seafood processing effluents on the aquatic environment through physical-chemical characterization. Shellfish and finfish effluent samples were collected and characterized by biochemical oxygen demand (BOD5), chemical oxygen demand (COD), turbidity, total suspended solids (TSS), ammonia nitrogen (NH3-N), adsorbable organic halides (AOX), soluble BOD5 and soluble COD. Effluent concentration ranges were BOD5 (179 to 276mgL−1), COD (458 to 1717mgL−1), turbidity (28.8 to 88.3NTU), TSS (27.2 to 120.1mgL−1), NH3-N (1.5 to 12.9mgL−1) and AOX (3.2 and 0.4mgL−1) for flatfish and salmon processing effluents respectively, and cleanup shift AOX (3.5 and 0.5mgL−1). The characteristics of these effluents assessed have the potential to contaminate and degrade receiving water body environments. Improved performance may be possible with further treatment technology optimization on an effluent-specific basis.
Показать больше [+] Меньше [-]Effects of pH on the growth and NH4-N uptake of Skeletonema costatum and Nitzschia closterium Полный текст
2017
Gu, Xingyan | Li, Keqiang | Pang, Kai | Ma, Yunpeng | Wang, Xiulin
Ocean acidification (OA) and eutrophication intensifies in coastal sea under anthropogenic impact. OA coupled with the NH4-N source effect in coastal water is likely to affect the planktonic ecosystem. In this work, Skeletonema costatum and Nitzschia closterium were chosen as typical species of diatom in Chinese coastal ecosystems to test the potential effect of OA and NH4-N. Results showed that the growth and NH4-N uptake of S. costatum and N. closterium were significantly inhibited by pH decline. The maximum uptake rate is higher than the maximum growth rate, implying that NH4-N was assimilated faster for S. costatum and N. closterium with decreasing pH. Therefore, the inhibition rate of the growth of the two diatoms by the coupling effect of OA and eutrophication (pH7.45) is higher that than in the coastal sea by the end of the 21st century (pH7.71).
Показать больше [+] Меньше [-]Effects of anthropogenic surfactants on the conversion of marine dissolved organic carbon and microgels Полный текст
2017
Shiu, Ruei-Feng | Lee, Chon-Lin
The possible impact of three types of anthropogenic surfactants on the ability of marine dissolved organic carbon (DOC) to form self-assembled microgels was evaluated. The behavior of existing native microgels was also examined in the presence of surfactants. These results reveal that the release of surfactants even at low concentrations into the aquatic environment could effectively hinder the self-assembly of DOC polymers. The extent of the size reduction had the following order: anionic, cationic, and non-ionic. Furthermore, charged surfactants can disrupt existing native microgels, converting large assemblies into smaller particles. One possible mechanisms is that surfactants are able to enhance the stability of DOC polymers and disrupt aggregates due to their surface charges and protein-denaturing activities. These findings suggest that the ecological system is altered by anthropogenic surfactants, and provide useful information for ecological assessments of different types of surfactants and raise warnings about surfactant applications.
Показать больше [+] Меньше [-]Petroleum hydrocarbon toxicity to corals: A review Полный текст
2017
Turner, Nicholas R. | Renegar, D Abigail
The proximity of coral reefs to coastal urban areas and shipping lanes predisposes corals to petroleum pollution from multiple sources. Previous research has evaluated petroleum toxicity to coral using a variety of methodology, including monitoring effects of acute and chronic spills, in situ exposures, and ex situ exposures with both adult and larval stage corals. Variability in toxicant, bioassay conditions, species and other methodological disparities between studies prevents comprehensive conclusions regarding the toxicity of hydrocarbons to corals. Following standardized protocols and quantifying the concentration and composition of toxicant will aid in comparison of results between studies and extrapolation to actual spills.
Показать больше [+] Меньше [-]Assessment of DDT, HCH and PAH contamination and associated ecotoxicological risks in surface sediments of coastal Tema Harbour (Ghana) Полный текст
2017
Botwe, Benjamin O. | Kelderman, Peter | Nyarko, Elvis | Lens, Piet N.L.
This study assessed DDTs, HCHs and PAHs contamination in sediments from the Tema Harbour (Ghana) and the associated ecotoxicological risks. The results showed widespread DDTs, HCHs and PAHs contamination in the harbour sediments with mean concentrations ranging from 6.0–12.8, 2.8–12.7 and 2750–5130μg·kg−1d·w, respectively. The silt-clay and total organic carbon contents of the sediments poorly correlated with the pollutant concentrations. DDTs and HCHs contamination relate to past use of DDT and lindane, which under the anoxic harbour conditions resulted in disproportionately higher concentrations of p,p′-DDD and γ-HCH in the sediments. No conclusion could be drawn on the sources of PAHs as either petrogenic or pyrogenic. The pollutant concentrations in the harbour sediments, particularly γ-HCH, may pose high ecotoxicological risks. In comparison to a previous study, this study indicates there has been a considerable reduction in PAH contamination in the Tema Harbour since the last major oil spill in 2007.
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