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Occurrence, potential health risk of heavy metals in aquatic organisms from Laizhou Bay, China 全文
2019
Heavy metal pollution is a serious environmental problem. Up to date, research regarding distribution, accumulation and potential risk assessment of metals in aquatic organisms in Laizhou Bay, China is scarce. This study aims to investigate metals in aquatic organisms in this region. The results demonstrated that great variability of metals content occurred among species and sampling locations. Fe was the most abundant metal, followed by Zn, Mn, Cu, Ni, Cr, Cd and Pb. Overall, shellfish and crab displayed high enrichment ability compared with fish and shrimp. There was no significant correlation between metals and samples weight, δ13C and δ15N values. Principal component analysis (PCA) indicated that metals in samples were mainly derived from anthropogenic activities. Health risk of metals was evaluated on the basis of estimated daily intake (EDI) and target hazard quotient (THQ) values. The results indicated that metals in studied seafood had no significant risks for ordinary consumers.
显示更多 [+] 显示较少 [-]Distribution, sources, and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in surface sediments of the Subei Shoal, China 全文
2019
In this study, 16 polycyclic aromatic hydrocarbons (PAHs) were detected in surface sediments of the Subei Shoal. Eleven of the 16 PAHs were detected, namely, Nap, Fl, Phe, Flu, Pyr, BaAnt, Chr, BaFlu, BaPyr, Ind-1,2,3-cdPyr, and BghiPer, and the remaining five (Acy, Ace, Ant, BkFlu, and DBahAnt) were not detected. Total PAH concentrations ranged from <DL to 25.24 ng/g dw, with an average of 5.88 ng/g dw. The highest concentrations were found in the intermediate sections (stations 6–1), followed by those in the northernmost regions (stations 9–5). The lowest concentrations were found in the south of section 2. High-molecular-weight PAHs (4 and 5 rings) were found to be dominant, constituting 70% of the PAHs tested. Principal component analysis showed that PAHs in sediments came mainly from coal combustion, transportation (oil combustion), coke processing, and petroleum sources. Both effect range low/effect range median values and mean effects range–median quotient showed that PAHs were present at a low toxicity risk level in the Subei Shoal.
显示更多 [+] 显示较少 [-]Distribution and origination of zinc contamination in newly reclaimed heterogeneous dredger fills: Field investigation and numerical simulation 全文
2019
Heavy metal elements, including Zn, Cd, As, Ni, Cu, Pb and Cr, were detected in soils (no deeper than 75 m) from newly reclaimed zones of Shanghai, China. The Zn concentration exceeded soil quality limits. The Zn contamination was tested in both dredger fills and sedimentary layers (①₃–₃, ②₃, ④ and ⑤₁–₁). However, it was not detected in layer ⑤₁–₂–⑨. PCA and HCA analysis show that exogenous Zn probably was the contaminant source of dredger fills before the fills were dredged from the neighboring waters. Stochastic heterogeneity of the dredger fills affects the Zn-depollution remarkably. Numerical simulations show both acid precipitation and widespread drainage channels in the zones contributed to Zn-decrease in the dredger fills no deeper than 1.2 m. Acid rainstorms work better than acid constant precipitation in Zn-remediation for layers below 0.4 m. To remove Zn contamination in deep dredger fills, un-consolidation of the fills should be utilized.
显示更多 [+] 显示较少 [-]Depth-related change of sulfate-reducing bacteria community in mangrove sediments: The influence of heavy metal contamination 全文
2019
This study provides new insight towards the effects of heavy metal contamination on sulfate-reducing bacteria (SRB) in mangrove ecosystem. We investigated SRB communities in mangrove sediments (0–30 cm depth) from Futian, Xixiang and Shajing mangrove wetlands in Shenzhen, China, with different heavy metal contamination levels. The results showed that SRB community abundance (1.71 × 107–3.04 × 108 dsrB gene copies g−1 wet weight sediment) was depth-related and significantly correlated with Cd and Ni concentrations. The α-diversity indices of SRB community (Chao1 = 21.25–84.50, Shannon = 2.31–2.96) were significantly correlated with Cd level in mangrove sediments. Desulfobacteraceae, Desulfobulbaceae and Syntrophobacteraceae acted as major SRB groups in mangrove sediments, and Syntrophobacteraceae was most sensitive to metal contamination. UniFrace clustering analysis revealed that SRB community structure was influenced by the heavy metal concentrations. Moreover, redundancy analysis indicated that Cd and total phosphorus were the major environmental factors affecting the SRB structure in mangrove sediments.
显示更多 [+] 显示较少 [-]Assessment of a coastal lagoon metal distribution through natural and anthropogenic processes (SE, Brazil) 全文
2019
Beraldi, Gaby Quintal F. | de Rezende, Carlos Eduardo | de Almeida, Marcelo Gomes | Carvalho, Carla | Lacerda, Luiz Drude de | de Farias, Roberto Nascimento | Vidal, Marcella | Souza, Michael Douglas P. | Molisani, Mauricio Mussi
The present study intends to assess the metal pollution of a eutrophic coastal lagoon, analyzing the long-term and actual metal content in surface sediments, suspended particles, aquatic macrophyte and fish species, and the loads emitted from natural processes and anthropogenic sources, including the relative emission of domestic untreated sewage. Distribution indicated contamination of suspended particles with Cd and the predominance of Pb in the bioavailable form in surface sediments which may explain Cd and Pb contamination in fish. Domestic untreated sewage was an important source of Cu and due to the lagoon's management, this source may be increasing the metal content in the lagoon's surface sediments. Soil loss, atmospheric deposition and solid waste disposal also contributed to metal inputs to the lagoon. Extensive contamination has been prevented by the lagoon's management such as sandbar opening. Metal retention within the watershed soils reduce the effective metal transference and lagoon pollution.
显示更多 [+] 显示较少 [-]PCDD/F and PCB levels in different tissues from dugongs (Dugong dugon) inhabiting the Queensland coastline 全文
2019
Vijayasarathy, S. | Weijs, L. | Grant, S. | Gallen, M. | Gaus, C.
Previous studies on PCDD/Fs and PCBs in dugong (Dugong dugon) blubber reported unexpectedly elevated TEQ levels. This study analysed archived blubber, muscle, liver and faeces obtained from dugongs from two areas along the Queensland coast. All samples showed detectable levels of PCDDs and PCBs, while PCDFs were consistently near or below LOQ. PCDD levels in dugongs contributed to a large proportion (<95%) of sum TEQ levels in all tissues (blubber: 6.7–38 pg g−1 lw, muscle: 5.7–96 pg g−1 lw, liver: 3.3–42 pg g−1 lw, faeces: 203 pg g−1 lw). Liver/blubber tissue ratios show that PCDDs are preferentially accumulated in the liver with higher degree of chlorination. The same trend was not so obvious with PCBs, which occasionally showed higher hepatic sequestration of lower chlorinated PCBs such as PCBs 28 and 77. PCDD congeners were dominated by OCDD which is similar to the profiles from the dugongs' food source, namely sediment and seagrass.
显示更多 [+] 显示较少 [-]Post-release breeding success of oil-rehabilitated and non-rehabilitated little blue penguins, Eudyptula minor, following the M/V Rena oil spill, New Zealand 全文
2019
Sievwright, Karin A. | Battley, Phil F. | McConnell, Helen M. | Chilvers, B. L. (Barbara Louise) | Morgan, Kerri J.
During the 2011 M/V Rena oil spill in Tauranga, New Zealand, 383 little blue penguins (LBP, Eudyptula minor) were oiled, rescued and rehabilitated, with 90.6% surviving to be released back to the wild. We monitored the post-release breeding success of rehabilitated LBPs to assess the effectiveness of the rehabilitation process. Breeding success was monitored during the first breeding season post-release (2012−13) to assess productivity for both rehabilitated and control penguins (breeding pairs of rehabilitated or non-oiled (control) birds). Egg laying, hatching and fledging success rates for pairs of rehabilitated and control penguins were both within ranges reported for other LBP colonies in Australia and New Zealand. The only significant difference between rehabilitated and control pairs was that hatching success was reduced in the first season after release for rehabilitated pairs. Overall, rehabilitation appeared to reverse most potential negative effects of oiling on the post-release breeding success of rehabilitated LBP.
显示更多 [+] 显示较少 [-]Arctic marine fish ‘biotransformation toxicity’ model for ecological risk assessment 全文
2019
Fahd, Faisal | Veitch, Brian | K̲h̲ān, Faiṣal
Oil and gas exploration and marine transport in the Arctic region have put the focus on the ecological risk of the possibly exposed organisms. In the present study, the impacts of sea ice, extreme light regime, various polar region-specific physiological characteristics in polar cod (Boreogadus saida) and their effects on xenobiotic distribution and metabolism are studied. A Bayesian belief network is used to model individual fish toxicity. The enzyme activity in the fish liver and other pertinent organs is used as a proxy for cellular damage and repair and is subsequently linked to toxicity in polar cod. Seasonal baseline variation in enzyme production is also taken into consideration. The model estimates the probability of exposure concentration to cause cytotoxicity and circumvents the need to use the traditionally obtained No Observed Effect Concentration (NOEC). Instead, it uses biotransformation enzyme activity as a basis to estimate the probability of individual cell damages.
显示更多 [+] 显示较少 [-]Insight into tidal disturbance on colonization surveys for marine bioassessment using periphytic ciliates based on biological trait analysis 全文
2019
Zhong, Xiaoxiao | Xu, Guangjian | Min, Gi-Sik | Kim, Sanghee | Xu, Henglong
To understand tidal disturbance on the colonization dynamics in community functioning of the ciliates in marine ecosystems, a 1-month survey was conducted using the conventional slide system (CS) and the polyurethane foam enveloped slide system (PFES) in Korean coastal waters. The results showed considerable differences were detected in community functioning parameters between the two systems. The vagile, flattened forms feeding on periphytic microalgae showed a higher community-weighted mean (CWM) value, and the solitary-colonial pattern represented a more stable temporal variability during the colonization in the PFES system than the CS system. The temporal shift in community functioning of the ciliates showed different ways in both systems. The functional diversity measures generally levelled off at more stable values in the communities with ages of 13–15 days in the PFES system than the CS system. These results imply that the PFES system may be a workable method for bioassessment in marine ecosystems.
显示更多 [+] 显示较少 [-]Introductions and transfers of species by ballast water in the Adriatic Sea 全文
2019
Gollasch, Stephan | Hewitt, Chad L. | Bailey, Sarah | David, Matej
Following the Editorial addressing the BALMAS project, we open the ballast water management special issue for the Adriatic Sea by providing background information on non-indigenous species and the mechanisms (vectors) of transport. Problems allocating introduction mechanisms for various species with certainty are described; in general, key introduction mechanisms are shipping, with ballast water and biofouling as dominant vectors, and aquaculture activities. The dominant mechanisms for introduction may differ through time, between regions and across species. We highlight ballast water as the focus of an international convention to prevent future introductions, reviewing management options and suggesting future research needs. This assessment is not restricted in application to the Adriatic Sea, but is applicable to other coastal waters. Results of such future work may contribute to the experience building phase planned by the International Maritime Organization for a harmonised implementation of the Ballast Water Management Convention.
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