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Tributary inflows enhance the microplastic load in the estuary: A case from the Qiantang River Full text
2020
Zhao, Wenlu | Huang, Wei | Yin, Mingchao | Huang, Peng | Ding, Yongcheng | Ni, Xuan | Xia, Huilong | Liu, Huijun | Wang, Guoqin | Zheng, Haowen | Cai, Mingang
Microplastics (MPs) in the surface water of the Qiantang River and its tributaries were investigated in this study, to evaluate the contribution of riverine discharge on emerging pollution load in the Hangzhou Bay. The abundance of MPs (mean 1183 ± 269 particles/m³) showed spatially and temporally heterogeneous in the surface water. Polyamide, polyester, and polyethylene teraphalate were the major components, accounting for 77.4% of all polymer types. Fiber was the most common shape, indicating the potential anthropogenic sources of MPs. The MPs flux from the Qiantang River to the Hangzhou Bay was estimated to be 2831 tons/year, implying the importance of riverine discharge in an estuarine bay. The inputs from the complicated tributaries system led to a 20-fold increase of MPs flux, and would significantly improve their budget of downstream and estuary, so we suggested the control and management on plastic pollution should be strengthened in all aspects.
Show more [+] Less [-]Persistent organic pollutants in sediments of the Wouri Estuary Mangrove, Cameroon: Levels, patterns and ecotoxicological significance Full text
2020
Mbusnum, Kevin G. | Malleret, Laure | Deschamps, Pierre | Khabouchi, Imen | Asia, Laurence | Lebarillier, Stéphanie | Menot, Guillemette | Onguene, Raphael | Doumenq, Pierre
The anthropogenic impact in the Wouri Estuary Mangrove located in the rapidly developing urban area of Douala, Cameroon, Africa, was studied. A set of 45 Persistent Organic Pollutant were analysed in surficial mangrove sediments at 21 stations. Chlorinated Pesticides (CLPs), Polychlorinated Biphenyls (PCBs) and Polycyclic Aromatic Hydrocarbons (PAHs) have concentrations ranging from 2.2 – 27.4, and 83 – 544 ng/g, respectively. The most abundant CLPs were endosulfan, alachlor, heptachlor, lindane (γ-HCH) and DDT, which metabolites pattern revealed recent use. Selected PAHs diagnostic ratios show pyrolytic input predominantly. The sum of 7 carcinogenic PAHs (ΣC-PAHs) represented 30 to 50% of Total PAHs (TPAHs). According to effect-based sediment quality guidelines, the studied POPs levels imply low to moderate predictive biological toxicity. This study contributes to depict how far water resources are shifting within what is now termed the Anthropocene due to increasing local pressures in developing countries or African countries.
Show more [+] Less [-]Mercury accumulation in fish species along the Portuguese coast: Are there potential risks to human health? Full text
2020
Costa, Filipe | Coelho, João P. | Baptista, Joana | Martinho, Filipe | Pereira, Maria E. | Pardal, Miguel A.
This paper aimed at evaluating the total mercury content in five common fish species from the western European Atlantic coastal waters, and the associated risk of consumption. Mercury concentrations in muscle of Atlantic mackerel (Scomber scombrus), Atlantic chub mackerel (Scomber colias), European anchovy (Engraulis encrasicolus), Atlantic horse mackerel (Trachurus trachurus) and European pilchard (Sardina pilchardus) ranged from 0.003 to 0.20 mg kg⁻¹ wet weight, and no significant differences were observed between the average concentration in each species. A significant increasing trend in mercury content with fish size was observed for all species (except for European anchovy), suggesting mercury bioaccumulation throughout their life cycle. Still, the mercury content was far below the European Food Safety Authority and World Health Organization food safety thresholds in all species, highlighting the low risk to human health due to the ingestion of these species and the importance of consumer options for risk reduction.
Show more [+] Less [-]Underwater acoustic characterisation of unexploded ordnance disposal using deflagration Full text
2020
Robinson, S. P. (Stephen P.) | Wang, Lian | Cheong, Sei-Him | Lepper, P. A. (Paul A.) | Marubini, Francesca | Hartley, John P.
The seabed off North West Europe contains much unexploded ordnance (UXO), posing a hazard to offshore developments such as windfarms. The typical removal method is through high-order detonation of a donor charge placed adjacent to the UXO. This method poses a risk of injury or death to marine mammals and other fauna from the high sound levels produced. This paper describes a controlled field experiment to compare the sound produced by high-order detonations with a low-order disposal method called deflagration, which uses a shaped charge of modest size, is less energetic, and offers reduced environmental impact from lower acoustic output. The results demonstrate a substantial reduction over high order detonation, with the peak sound pressure level and sound exposure level being more than 20 dB lower for the deflagration, and with the acoustic output depending only on the size of the shaped charge (rather than the size of the UXO).
Show more [+] Less [-]The distribution characteristics of polychlorinated biphenyls (PCBs) in the surface sediments of Ross Sea and Drake Passage, Antarctica: A 192 congeners analysis Full text
2020
Deng, Zhaochao | Han, Xibin | Chen, Chunlei | Wang, Heng | Ma, Bingbing | Zhang, Dongdong | Zhang, Zhichao | Zhang, Chunfang
A total of 23 sediment samples are collected from Ross Sea and Drake Passage to investigate the distribution characteristics of polychlorinated biphenyls (PCBs) in the Antarctic marine sediments. Over 51 kinds of PCBs are detected through exhaustive searches using multiple reaction monitoring system. The results show that the concentration of individual PCB congener and total PCBs vary greatly among sampling sites, ranging from not detected to 49.75 ng g⁻¹ and 3.77 to 246.86 ng g⁻¹, respectively. The average PCBs level in Ross Sea is ten times higher than that in Drake Passage. Two different homologues, hexa- and tetra-CBs, give high contributions to ∑PCBs level in most samples from Ross Sea and Drake Passage, respectively. Our results support that the marine sediments might be an important sink for PCBs. Besides, the biological pump and the primary productivity might be responsible for the distribution differences of PCBs between Ross Sea and Drake Passage.
Show more [+] Less [-]Latitudinal, sex and inter-specific differences in mercury and other trace metal concentrations in Adélie and Emperor penguins in the Ross Sea, Antarctica Full text
2020
Pilcher, Natalie | Gaw, Sally | Eisert, Regina | Horton, Travis W. | Gormley, Andrew M. | Cole, Theresa L. | Lyver, Phil O'B.
We sought to determine mercury (Hg) and other trace metal concentrations in Adélie (Pygoscelis adeliae) and emperor penguin (Aptenodytes forsteri) breast feathers from the Ross Sea, Antarctica, and relate those concentrations to the trophic position and the habitats in which each of these species forage. Adélie penguin feathers from the southern Ross Sea colonies were higher in Hg than those sampled further north in the Ross Sea, potentially due to greater exposure to local sources, such as volcanism. Female Adélie penguins had lower feather total Hg concentrations than males. This may reflect female penguin's capacity to eliminate Hg through the egg development and laying process, or the larger and/or older prey items that male birds can consume, reflected by their higher trophic position. Emperor penguins have higher Hg concentrations than Adélie penguins which is also partially explained by Adélie penguins feeding at lower trophic levels than emperor penguins.
Show more [+] Less [-]Petroleum hydrocarbons in semipermeable membrane devices deployed in the Northern Gulf of Mexico and Florida keys following the Deepwater Horizon incident Full text
2020
Bargar, Timothy A. | Stout, Scott A. | Alvarez, David
The Deepwater Horizon (DWH) oil spill from April to July of 2010 contaminated Gulf of Mexico waters through release of an estimated 4.1 × 10⁶ barrels of oil. Beginning in June of 2010, semipermeable membrane devices (SPMDs) were deployed near areas with sensitive marine habitats (Alabama Alps and Western Shelf) potentially exposed to that oil. Elevated TPAH50 concentrations, flux rates and similarity of histograms and diagnostic ratios for polycyclic aromatic hydrocarbons (PAH) from SPMDs to weathered floating oil collected during the DWH spill indicates the Alabama Alps habitats were affected. While not affected by oil from the DWH spill, the temporal pattern of PAH contamination of SPMDs deployed near the Western Shelf between July 2010 and March 2011 could indicate prevailing currents affected contaminant transport to the Western Shelf Area (East and West Flower Garden, Sonnier, and Stetson Banks) from non-DWH sources, including oil and gas exploration, shipping, and Mississippi River effluent.
Show more [+] Less [-]Growth and nutrient uptake of Myriophyllum spicatum under different nutrient conditions and its potential ecosystem services in an enclosed sea area in the East China Sea Full text
2020
Bao, Yanlin | Huo, Yuanzi | Duan, Yuanliang | He, Peimin | Ng, Mee Kam | Yang, Ne | Sun, Bin
We investigated the growth and nutrient uptake of Myriophyllum spicatum under different nutrient conditions and evaluated its implications for ecosystem services in an enclosed area of Jinshan. The specific growth rate ranged from 1.29%–4.37%/day, and the dissolved inorganic carbon and nitrogen, and phosphorus uptake rates were 1.30–1.62, 0.040–0.453, and 0.003–0.027 mg/(g∙day), respectively, under different nutrient conditions. The O₂-production and carbon-sequestration efficiencies in the field were 154.30 and 1.25 mg/(g DW∙h), respectively. The average removal efficiencies of NH₄⁺-N, NO₃⁻-N, NO₂⁻-N, and PO₄³⁻-P were 43.05%, 97.03%, 64.26%, and 59.24%, respectively, in M. spicatum-cultivated areas compared with in the open sea. Harvesting of M. spicatum removed 12,936.87, 1289.97 and 114.81 kg of carbon, nitrogen, and phosphorus, respectively, from seawater in Jinshan in Nov, 2018. In conclusion, M. spicatum is a good candidate for integrated macrophyte/animal multi-trophic aquaculture in terms of nutrient extraction and economic diversification in low-salinity environments.
Show more [+] Less [-]Toxicological effects of graphene on mussel Mytilus galloprovincialis hemocytes after individual and combined exposure with triphenyl phosphate Full text
2020
Meng, Xiangjing | Li, Fei | Wang, Xiaoqing | Liu, Jialin | Ji, Chenglong | Wu, Huifeng
Graphene nanoparticles are increasingly released into the aquatic environment with the growth of production. However, there are rare investigations focusing on the interaction of nanoparticles with other contaminants. Triphenyl phosphate (TPP) is a frequently detected organophosphate flame retardant in the environment. This study aimed to assess the joint effects of graphene and TPP on Mytilus galloprovincialis hemocytes. Oxidative stress could be induced by graphene and TPP in mussel hemocytes, which could further cause apoptosis, DNA damage and decrease in the lysosomal membrane stability (LMS). Moreover, hemocytes could internalize graphene, thereby resulting in oxidative stress. The oxidative stress and DNA damage in hemocytes were increased in the graphene-exposed group, but significantly reduced after combined exposure of graphene and TPP. The up-regulated genes, including NF-κB, Bcl-2 and Ras, were mainly associated with reduced apoptosis and DNA damage after co-exposure to graphene and TPP.
Show more [+] Less [-]Microplastics ingestion by blue panchax fish (Aplocheilus sp.) from Ciliwung Estuary, Jakarta, Indonesia Full text
2020
Cordova, Muhammad Reza | Riani, Etty | Shiomoto, Akihiro
Plastic pollution has a detrimental effect on marine environments, and there is limited information regarding its ingestion by biota, which is the primary consumer. Therefore, this research aims to assess microplastic ingestion by blue panchax fish (Aplocheilus sp.). To achieve this, microplastics were extracted and identified from Ciliwung estuary, coastal waters in North Jakarta, and the Aplocheilus sp. Its various forms and sizes were found in river flow (9.37 ± 1.37 particles/m³), coastal waters (8.48 ± 9.43 particles/m³), and in 75% samples of Aplocheilus sp. (1.97 particles/individual). The microplastic size which was of highest concentration in Aplocheilus sp. was relatively small, ranging from 300 to 500 μm. This small size indicates that the fish has difficulty in distinguishing between their food and the microplastics. Further, there was a possibility of the absorption of other pollutants by the plastics. Therefore, an in-depth study on the effects of plastic ingestion on aquatic life, biomagnification, exposure, chemical toxicity, and socio-economy is recommended.
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