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Environmental consequences of the flooding of the Bay Park Sewage Treatment Plant during Superstorm Sandy
2017
Swanson, R Lawrence | Wilson, Robert | Brownawell, Bruce | Willig, Kaitlin
Failure of the Bay Park Sewage Treatment Plant (STP) during Superstorm Sandy led to adverse effects in the waters of Hempstead Bay, Long Island, NY. These appear to be related to large discharges of partially treated sewage through its primary and auxiliary outfalls. Modeled dilution discharges indicate that sewage infiltrated the bay, remaining up to 10days. Water column impacts included salinity and dissolved oxygen declines, and biological oxygen demand and nitrogen concentration increases. While the STP does not appear to have released fecal coliform, there were elevated levels of enterococci within the bay for a considerable period following the storm, probably from multiple sources.The STP's reduced functioning and associated environmental impacts, even with resilience upgrades, are not conducive to removing the bay from the list of Impaired Water Bodies. The results reinforce the need to transfer the discharge from the existing outfall to the ocean.
Afficher plus [+] Moins [-]Determination and speciation of cadmium in microcosms with Bunodosoma caissarum and Perna perna using isotopically enriched 116Cd
2017
Rizzini Ansari, Nafisa | Fernández Iglesias, Nerea | Cordeiro, Renato Campello | Fernandez, Marcos Antônio | Bettmer, Jörg
The study of the uptake and distribution of elements in marine environments is of great interest for understanding their pathways and accumulation. Here, we investigated in laboratory experiments the accumulation behavior of Cd in the sea anemone Bunodosoma caissarum and the mussel Perna perna. Specimens were incubated with isotopically enriched 116Cd in aquariums. Cd concentrations in the seawater and in the tissues of B. caissarum and P. perna were followed by inductively coupled plasma-mass spectrometry (ICP-MS) by means of isotope dilution analysis. Bioconcentration factors for B. caissarum and P. perna exposed to 0.9μg·L−1 of 116Cd were determined to be 80.5 and 850, respectively. P. perna specimens exposed to 4.5μg·L−1 of 116Cd reached 530. Cytosolic proteins associated with Cd from the tissues were extracted and further analyzed by size-exclusion chromatography coupled to ICP-MS. Cd accumulation could be detected in both organisms ranging from high-molecular to low-molecular species.
Afficher plus [+] Moins [-]Optimization of a cloud point extraction procedure with response surface methodology for the quantification of dissolved iron in produced water from the petroleum industry using FAAS
2017
Gondim, Tamyris A. | Guedes, Jhonyson A.C. | Ribeiro, Livia P.D. | Lopes, Gisele S. | Matos, Wladiana O.
The characterization of inorganic elements in the produced water (PW) samples is a difficult task because of the complexity of the matrix. This work deals with a study of a methodology for dissolved Fe quantification in PW from oil industry by flame atomic absorption spectrometry (FAAS) after cloud point extraction (CPE). The procedure is based on the CPE using PAN as complexing agent and Triton X-114 as surfactant. The best conditions for Fe extraction parameters were studied using a Box-Behnken design. The proposed method presented a LOQ of 0.010μgmL−1 and LOD of 0.003μgmL−1. The precision of the method was evaluated in terms of repeatability, obtaining a coefficient of variation of 2.54%. The accuracy of the method was assessed by recovery experiments of Fe spiked that presented recovery of 103.28%. The method was applied with satisfactory performance to determine Fe by FAAS in PW samples.
Afficher plus [+] Moins [-]The 2014 summer coral bleaching event in subtropical Hong Kong
2017
Xie, James Y. | Lau, Dickey C.C. | Kei, Keith | Yu, Vriko P.F. | Chow, Wing-Kuen | Qiu, Jian-Wen
We reported a coral bleaching event that occurred in August–September 2014 in Hong Kong waters based on video transect surveys conducted at eight sites. The bleaching affected eight species of corals with different growth forms. Bleaching at seven of the eight study sites was minor, affecting only 0.4–5.2% colonies and 0.8–10.0% coral-covered area. Sharp Island East, however, suffered from a moderate level of bleaching, with 13.1% colonies and 30.1% coral-covered area affected. Examination of the government's environmental monitoring data indicated that abnormal water quality conditions preceding and during the bleaching event. Follow-up field surveys of tagged colonies showed that 76% of them had fully recovered, 12% partially recovered, and 12% suffered from mortality. These results indicate that the subtropical corals of Hong Kong are not immune to bleaching, and there is a need to study their responses under climate change scenarios.
Afficher plus [+] Moins [-]Determination and assessment of phthalate esters content in sediments from Kaohsiung Harbor, Taiwan
2017
Chen, Chih-Feng | Chen, Chiu-Wen | Ju, Yun-Ru | Dong, Cheng-Di
Phthalate esters (PAEs) are known organic endocrine disruptors. The distribution of 10 PAEs in sediments of Kaohsiung Harbor of Taiwan was studied using organic solvents extraction and quantified by gas chromatography/mass spectrometry. The average concentration of total PAEs (ΣPAEs) in the sediment was 8713±11,454ng/g dw with di-(2-ethylhexyl) phthalate (DEHP) (3630ng/g-dw) and diisononyl phthalate (DiNP) (3497ng/g dw) being the major species, which constitutes of 41.7% and 40.1% of ΣPAEs. PAEs concentration was relatively high near the river mouths, especially in Love River mouth, and diminished toward the harbor. Based on the sediment quality guidelines developed from previous studies, several of the observed PAE levels exceeded the Maximum Contaminant Level, especially for DEHP and thus may cause adverse effect in aquatic organisms.
Afficher plus [+] Moins [-]Effects of high salinity from desalination brine on growth, photosynthesis, water relations and osmolyte concentrations of seagrass Posidonia australis
2017
Cambridge, M L | Zavala-Perez, A | Cawthray, G R | Mondon, J | Kendrick, G A
Highly saline brines from desalination plants expose seagrass communities to salt stress. We examined effects of raised salinity (46 and 54psu) compared with seawater controls (37psu) over 6weeks on the seagrass, Posidonia australis, growing in tanks with the aim of separating effects of salinity from other potentially deleterious components of brine and determining appropriate bioindicators. Plants survived exposures of 2–4weeks at 54psu, the maximum salinity of brine released from a nearby desalination plant. Salinity significantly reduced maximum quantum yield of PSII (chlorophyll a fluorescence emissions). Leaf water potential (Ψw) and osmotic potential (Ψπ) were more negative at increased salinity, while turgor pressure (Ψp) was unaffected. Leaf concentrations of K+ and Ca2+ decreased, whereas concentrations of sugars (mainly sucrose) and amino acids increased. We recommend leaf osmolarity, ion, sugar and amino acid concentrations as bioindicators for salinity effects, associated with brine released in desalination plant outfalls.
Afficher plus [+] Moins [-]In situ biomonitoring of air quality in rural and urban environments of Mexico Valley through genotoxicity evaluated in wild plants
2017
Gómez-Arroyo, Sandra | Cortés-Eslava, Josefina | Loza-Gómez, Paola | Arenas-Huertero, Francisco | de la Mora, Michel Grutter | Morton Bermea, Ofelia
Air pollution is one the main causes of DNA damage in living organisms. Continuous exposure to the complex mixture of gases of polluted atmospheres affects health in many ways. Sentinel organisms are good biological models to assess the genotoxic damage caused by various chemicals such as atmospheric pollutants.In this study the plant species Taraxacum officinale and Robinsonecio gerberifolius were exposed during 2015, in the dry and rainy seasons, for 0, 2, 4 and 6 weeks to two different atmospheres of Mexico Valley, one rural in Altzomoni atmospheric observatory (ALTZ) and other urban in the atmospheric observatory of Centro de Ciencias de la Atmósfera (CCA), located in Universidad Nacional Autónoma de México (UNAM).Leaves of exposed plants were processed to analyze genotoxic damage by single-cell gel electrophoresis. To found any relation, the presence of pollutants in the atmosphere of both sites was analyzed with a Cavity Ring-Down Spectrometer (CRDS) and in the leaves the presence of heavy metals with an inductively coupled plasma mass spectrometer.Single-cell gel electrophoresis results showed higher damage in the leaves exposed to higher pollution in the UNAM atmospheric station in comparison to the ALTZ and controls, which was maintained in growth chambers under controlled conditions. Significant differences between rainy and dry seasons were found. Chemical analysis showed a significant increase in various heavy metals, especially in rainy season in both exposure sites. Increased DNA damage observed in both plant species at CCA station could be caused by accumulation trough six weeks.
Afficher plus [+] Moins [-]An algorithm for modeling entrainment and naturally and chemically dispersed oil droplet size distribution under surface breaking wave conditions
2017
Li, Zhengkai | Spaulding, Malcolm L. | French-McCay, Deborah
A surface oil entrainment model and droplet size model have been developed to estimate the flux of oil under surface breaking waves. Both equations are expressed in dimensionless Weber number (We) and Ohnesorge number (Oh, which explicitly accounts for the oil viscosity, density, and oil-water interfacial tension). Data from controlled lab studies, large-scale wave tank tests, and field observations have been used to calibrate the constants of the two independent equations. Predictions using the new algorithm compared well with the observed amount of oil removed from the surface and the sizes of the oil droplets entrained in the water column. Simulations with the new algorithm, implemented in a comprehensive spill model, show that entrainment rates increase more rapidly with wind speed than previously predicted based on the existing Delvigne and Sweeney's (1988) model, and a quasi-stable droplet size distribution (d<~50μm) is developed in the near surface water.
Afficher plus [+] Moins [-]Tree bark as bioindicator of metal accumulation from road traffic and air quality map: A case study of Chiang Mai, Thailand
2017
Janta, Rungruang | Chantara, Somporn
Trees have been recognized as air quality bioindicators, but they have still not been fully implemented in tropical areas. In this study, bark of Cassia fistula was used to inspect accumulation of air pollutants (metals) emitted from road traffic in the city of Chiang Mai, Thailand. The mean concentrations of metal accumulated on tree bark (ng/cm2) in descending order were Al (1,238) > Fe (707) > Zn (162) » Cu (21.1) » Pb (6.37) > Cr (2.14). Correlations of Enrichment Factors: EFTS (metal concentrations on bark compared to those in soil) among metals were relatively strong (r > 0.6) meaning that they were probably generated from the same sources. Moreover, principal component analysis and cluster analysis of EFTS values revealed that Al and Fe were generated from soil resuspension that were attached on vehicle wheels and on road surfaces, while Cr, Cu, Pb and Zn resulted directly from vehicle emissions. The results lead to the conclusion that tree bark is a good bioindicator for air pollutant accumulation in this area. In addition, pollution indices, including total geoaccumulation index (IGEO-tot) and pollution load index (PLI), were applied to generate air quality maps of the city. The maps illustrated that the most polluted areas in the city are the areas that have high traffic volume and building density, in which hospitals and schools are located. The degree of pollution presented in each area was influenced by both road traffic volume and density of buildings in relation to air ventilation capacity.
Afficher plus [+] Moins [-]Trace elements in Mediterranean seagrasses: Accumulation, tolerance and biomonitoring. A review
2017
Bonanno, Giuseppe | Orlando Bonaca, Martina
This study investigated the state of the art on trace elements in Mediterranean seagrasses, and their close environment (seawater and sediment). The analyzed species were Posidonia oceanica, Cymodocea nodosa, Halophila stipulacea, Zostera marina and Zostera noltei. All these species showed high tolerance to pollution and high capacity of accumulation of trace elements. Seagrasses also showed similar patterns of accumulation: the highest concentrations of As, Hg and Pb were found in the roots, whereas those of Cd, Cr, Cu, Mn, Ni and Zn were found in the leaves. Phytotoxic levels in seagrasses are unknown for most trace elements. The accumulation of trace elements in seagrasses is widely recognized as a risk to the whole food web, but the real magnitude of this risk is still uncertain. Seagrasses are known to act as trace element bioindicators, but this potential is still poorly valued for the creation of biomonitoring networks.
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