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Vitamin C modulates cadmium-induced hepatic antioxidants’ gene transcripts and toxicopathic changes in Nile tilapia, Oreochromis niloticus
2016
El-Sayed, Yasser S. | El-Gazzar, Ahmed M. | El-Nahas, Abeer F. | Ashry, Khaled M.
Cadmium (Cd) is one of the naturally occurring heavy metals having adverse effects, while vitamin C (L-ascorbic acid) is an essential micronutrient for fish, which can attenuate tissue damage owing to its chain-breaking antioxidant and free radical scavenger properties. The adult Nile tilapia fish were exposed to Cd at 5 mg/l with and without vitamin C (500 mg/kg diet) for 45 days in addition to negative and positive controls fed with the basal diet and basal diet supplemented with vitamin C, respectively. Hepatic relative mRNA expression of genes involved in antioxidant function, metallothionein (MT), glutathione S-transferase (GST-α1), and glutathione peroxidase (GPx1), was assessed using real-time reverse transcription polymerase chain reaction (RT-PCR). Hepatic architecture was also histopathologically examined. Tilapia exposed to Cd exhibited upregulated antioxidants’ gene transcript levels, GST-⍺1, GPx1, and MT by 6.10-, 4.60-, and 4.29-fold, respectively. Histopathologically, Cd caused severe hepatic changes of multifocal hepatocellular and pancreatic acinar necrosis, and lytic hepatocytes infiltrated with eosinophilic granular cells. Co-treatment of Cd-exposed fish with vitamin C overexpressed antioxidant enzyme-related genes, GST-⍺1 (16.26-fold) and GPx1 (18.68-fold), and maintained the expression of MT gene close to control (1.07-fold), averting the toxicopathic lesions induced by Cd. These results suggested that vitamin C has the potential to protect Nile tilapia from Cd hepatotoxicity via sustaining hepatic antioxidants’ genes transcripts and normal histoarchitecture.
Afficher plus [+] Moins [-]Occurrence, fate, and risk assessment of vancomycin in two typical pharmaceutical wastewater treatment plants in Eastern China
2016
Qiu, Panzi | Guo, Xinyan | Zhang, Yi | Chen, Xingling | Wang, Na
Vancomycin (VCM) is an antibiotic, known medically as the deadline for defending against bacteria. In this study, the removal and fate of VCM were investigated in each treatment unit at two pharmaceutical wastewater treatment plants (PWWTPs) in eastern China. VCM was present in all wastewater and sludge samples of both PWWTPs. After the treatment procedure (the moving bed biofilm reactor technology for PWWTP1 and the modified anaerobic–anoxic–oxic technology for PWWTP2), total removal efficiencies were up to 99 %, corresponding to a reduction of two orders of magnitude of the influent concentrations in both PWWTPs. The aerobic tank dominated VCM removal. Mass balance flow analyses indicated that biodegradation (99.15 % for PWWTP1 and 99.51 % for PWWTP2) was the principle mechanism for removing VCM, while the contribution of sorption by sludge for both PWWTPs was negligible. However, the results of the environmental risk assessment of VCM in the effluents showed that the maximum trigger quotient values were much higher than 1 in both PWWTPs, indicating the non-negligible environmental and health risks. This is the first report of the fate and risks of VCM in pharmaceutical wastewater, and underscores the importance of PWWTPs as antibiotic pollution sources, even though wastewater management appeared efficient.
Afficher plus [+] Moins [-]Modeling the temporal variability of zinc concentrations in zinc roof runoff—experimental study and uncertainty analysis
2016
Sage, Jérémie | El Oreibi, Elissar | Saad, Mohamed | Gromaire, Marie-Christine
This study investigates the temporal variability of zinc concentrations from zinc roof runoff. The influence of rainfall characteristics and dry period duration is evaluated by combining laboratory experiment on small zinc sheets and in situ measurements under real weather conditions from a 1.6-m² zinc panel. A reformulation of a commonly used conceptual runoff quality model is introduced and its ability to simulate the evolution of zinc concentrations is evaluated. A systematic and sharp decrease from initially high to relatively low and stable zinc concentrations after 0.5 to 2 mm of rainfall is observed for both experiments, suggesting that highly soluble corrosion products are removed at early stages of runoff. A moderate dependence between antecedent dry period duration and the magnitude of zinc concentrations at the beginning of a rain event is evidenced. Contrariwise, results indicate that concentrations are not significantly influenced by rainfall intensities. Simulated rainfall experiment nonetheless suggests that a slight effect of rainfall intensities may be expected after the initial decrease of concentrations. Finally, this study shows that relatively simple conceptual runoff quality models may be adopted to simulate the variability of zinc concentrations during a rain event and from a rain event to another.
Afficher plus [+] Moins [-]Activities and vectors responsible for the biological pollution in the Taranto Seas (Mediterranean Sea, southern Italy): a review
2016
Cecere, E. | Petrocelli, A. | Belmonte, M. | Portacci, G. | Rubino, F.
Biological pollution, caused by the negative impact of alien species, also known as non-indigenous species (NIS), is regarded as one of the greatest threat to marine ecosystems. The recent upsurge in the number and spread of these species drew attention to putative vectors such as shipping and shellfish importation for culture and consumption. The port of Taranto in Southern Italy is a hub for several vectors as it serves commercial and military shipping, fishing and recreational boating, in addition to shellfish importation. An analysis of anthropogenic activities and possible vectors in Taranto Seas was recently carried out within the framework of the RITMARE Project, involving local stakeholders. Different categories of stakeholders answered dedicated questionnaires with a high degree of reticence, and this highlighted a general lack of awareness of the problems associated with alien species. Consequently, there is a strong need to instil a truly ecological awareness among the general public and stakeholders.
Afficher plus [+] Moins [-]Effects of nitrogen application rates on net annual global warming potential and greenhouse gas intensity in double-rice cropping systems of the Southern China
2016
Chen, Zhongdu | Chen, Fu | Zhang, Hailin | Liu, Shengli
The net global warming potential (NGWP) and net greenhouse gas intensity (NGHGI) of double-rice cropping systems are not well documented. We measured the NGWP and NGHGI including soil organic carbon (SOC) change and indirect emissions (IE) from double-crop rice fields with fertilizing systems in Southern China. These experiments with three different nitrogen (N) application rates since 2012 are as follows: 165 kgN ha⁻¹ for early rice and 225 kgN ha⁻¹ for late rice (N1), which was the local N application rates as the control; 135 kgN ha⁻¹ for early rice and 180 kgN ha⁻¹ for late rice (N2, 20 % reduction); and 105 kgN ha⁻¹ for early rice and 135 kgN ha⁻¹ for late rice (N3, 40 % reduction). Results showed that yields increased with the increase of N application rate, but without significant difference between N1 and N2 plots. Annual SOC sequestration rate under N1 was estimated to be 1.15 MgC ha⁻¹ year⁻¹, which was higher than those under other fertilizing systems. Higher N application tended to increase CH₄ emissions during the flooded rice season and significantly increased N₂O emissions from drained soils during the nonrice season, ranking as N1 > N2 > N3 with significant difference (P < 0.05). Two-year average IE has a huge contribution to GHG emissions mainly coming from the higher N inputs in the double-rice cropping system. Reducing N fertilizer usage can effectively decrease the NGWP and NGHGI in the double-rice cropping system, with the lowest NGHGI obtained in the N2 plot (0.99 kg CO₂-eq kg⁻¹ yield year⁻¹). The results suggested that agricultural economic viability and GHG mitigation can be simultaneously achieved by properly reducing N fertilizer application in double-rice cropping systems.
Afficher plus [+] Moins [-]Effects of pharmaceuticals and personal care products on marine organisms: from single-species studies to an ecosystem-based approach
2016
Prichard, Emma | Granek, Elise F.
Pharmaceuticals and personal care products (PPCPs) are contaminants of emerging concern that are increasing in use and have demonstrated negative effects on aquatic organisms. There is a growing body of literature reporting the effects of PPCPs on freshwater organisms, but studies on the effects of PPCPs to marine and estuarine organisms are limited. Among effect studies, the vast majority examines subcellular or cellular effects, with far fewer studies examining organismal- and community-level effects. We reviewed the current published literature on marine and estuarine algae, invertebrates, fish, and mammals exposed to PPCPs, in order to expand upon current reviews. This paper builds on previous reviews of PPCP contamination in marine environments, filling prior literature gaps and adding consideration of ecosystem function and level of knowledge across marine habitat types. Finally, we reviewed and compiled data gaps suggested by current researchers and reviewers and propose a multi-level model to expand the focus of current PPCP research beyond laboratory studies. This model includes examination of direct ecological effects including food web and disease dynamics, biodiversity, community composition, and other ecosystem-level indicators of contaminant-driven change.
Afficher plus [+] Moins [-]Impact of land use changes on water quality in headwaters of the Three Gorges Reservoir
2016
Yang, Huicai | Wang, Guoqiang | Wang, Lijing | Zheng, Binghui
The assessment of spatial and temporal variation of water quality influenced by land use is necessary to manage the environment sustainably in basin scales. Understanding the correlations between land use and different formats of nonpoint source nutrients pollutants is a priority in order to assess pollutants loading and predicting the impact on surface water quality. Forest, upland, paddy field, and pasture are the dominant land use in the study area, and their land use pattern status has direct connection with nonpoint source (NPS) pollutant loading. In this study, two land use scenarios (1995 and 2010) were used to evaluate the impact of land use changes on NPS pollutants loading in basins upstream of Three Gorges Reservoir (TGR), using a calibrated and validated version of the soil and water assessment tool (SWAT) model. The Pengxi River is one of the largest tributaries of the Yangtze River upstream of the TGR, and the study area included the basins of the Dong and Puli Rivers, two major tributaries of the Pengxi River. The results indicated that the calibrated SWAT model could successfully reproduce the loading of NPS pollutants in the basins of the Dong and Puli Rivers. During the 16-year study period, the land use changed markedly with obvious increase of water body and construction. Average distance was used to measure relative distribution patterns of land use types to basin outlets. Forest was mainly distributed in upstream areas whereas other land use types, in particular, water bodies and construction areas were mainly distributed in downstream areas. The precipitation showed a non-significant influence on NPS pollutants loading; to the contrary, interaction between precipitation and land use were significant sources of variation. The different types of land use change were sensitive to NPS pollutants as well as land use pattern. The influence of background value of soil nutrient on NPS pollutants loading was evaluated in upland and paddy field. It was found that total nitrogen (TN) and total phosphorous (TP) in upland were more sensitive to NPS pollutants loading than in paddy fields. The results of this study have implications for management of the TGR to reduce the loading of NPS pollutants into downstream water bodies.
Afficher plus [+] Moins [-]Polycyclic aromatic hydrocarbon-contaminated soils: bioaugmentation of autochthonous bacteria and toxicological assessment of the bioremediation process by means of Vicia faba L
2016
Ruffini Castiglione, Monica | Giorgetti, Lucia | Becarelli, Simone | Siracusa, Giovanna | Lorenzi, Roberto | Di Gregorio, Simona
Two bacterial strains, Achromobacter sp. (ACH01) and Sphingomonas sp. (SPH01), were isolated from a heavily polycyclic aromatic hydrocarbon (PAH)-contaminated soil (5431.3 ± 102.3 ppm) for their capacity to use a mixture of anthracene, pyrene, phenanthrene and fluorene as sole carbon sources for growth and for the capacity to produce biosurfactants. The two strains were exploited for bioaugmentation in a biopile pilot plant to increase the bioavailability and the degradation of the residual PAH contamination (99.5 ± 7.1 ppm) reached after 9 months of treatment. The denaturing gel gradient electrophoresis (DGGE) profile of the microbial ecology of the soil during the experimentation showed that the bioaugmentation approach was successful in terms of permanence of the two strains in the soil in treatment. The bioaugmentation of the two bacterial isolates positively correlated with the PAH depletion that reached 7.9 ± 2 ppm value in 2 months of treatment. The PAH depletion was assessed by the loss of the phyto-genotoxicity of soil elutriates on the model plant Vicia faba L., toxicological assessment adopted also to determine the minimum length of the decontamination process for obtaining both the depletion of the PAH contamination and the detoxification of the soil at the end of the process. The intermediate phases of the bioremediation process were the most significant in terms of toxicity, inducing genotoxic effects and selective DNA fragmentation in the stem cell niche of the root tip. The selective DNA fragmentation can be related to the selective induction of cell death of mutant stem cells that can compromise offsprings.
Afficher plus [+] Moins [-]Cytotoxicity and genotoxicity induced by coal and coal fly ash particles samples in V79 cells
2016
León-Mejía, Grethel | Silva, Luis F. O. | Civeira, Matheus S. | Oliveira, Marcos L. S. | Machado, Miriana | Villela, Izabel Vianna | Hartmann, Andreas | Premoli, Suziane | Corrêa, Dione Silva | Da Silva, Juliana | Henriques, João Antônio Pêgas
Exposure to coal and coal ashes can cause harmful effects in in vitro and in vivo systems, mainly by the induction of oxidative damage. The aim of this work was to assess cytotoxic and genotoxic effects using the V79 cell line treated with coal and coal fly ash particles derived from a coal power plant located in Santa Catarina, Brazil. Two coal samples (COAL11 and COAL16) and two coal fly ash samples (CFA11 and CFA16) were included in this study. COAL16 was co-firing with a mixture of fuel oil and diesel oil. The comet assay data showed that exposure of V79 cells to coal and coal fly ash particles induced primary DNA lesions. Application of lesion-specific endonucleases (FPG and ENDO III) demonstrated increased DNA effects indicating the presence of high amounts of oxidative DNA lesions. The cytokinesis-block micronucleus cytome assay analysis showed that exposure of V79 cells to high concentrations of coal and coal fly ash particles induced cytotoxic effects (apoptosis and necrosis) and chromosomal instability (nucleoplasmic bridges, nuclear buds, and micronucleus (MN) formation). These results may be associated with compounds contained in the surface of the particles as hazardous elements, ultrafine/nanoparticles, and polycyclic aromatic hydrocarbons (PAHs) which were detected in the samples. Graphical abstract ᅟ
Afficher plus [+] Moins [-]Organochlorine pesticides and polychlorinated biphenyls in surface water around Beijing
2016
Shao, Yang | Han, Shen | Ouyang, Jie | Yang, Guosheng | Liu, Weihua | Ma, Lingling | Luo, Min | Xu, Diandou
Contaminant concentrations, sources, seasonal variation, and eco-toxicological risk of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in surface water around Beijing from summer to winter in 2015 and 2016 were investigated. The concentrations of ∑OCPs and ∑PCBs ranged from 9.81 to 32.1 ng L⁻¹ (average 15.1 ± 7.78 ng L⁻¹) and from 7.41 to 54.5 ng L⁻¹ (average 21.3 ± 1.87 ng L⁻¹), respectively. Hexachlorocyclohexane (HCHs) were the dominated contamination both in aqueous and particulate phase. For PCBs, lower chlorinated PCBs were the major contaminants. Compositions of HCHs, dichlorodiphenyltrichloroethane (DDTs), and PCBs indicated that the sources of OCPs and PCBs in water were due to historical usage in the study areas. For OCPs, there was an obvious variation among three seasons, while insignificant change was shown for PCBs. Water quality standards for China’s surface water were not exceeded in this study. Concentrations at Miyun Reservoir, the primary source of drinking water to Beijing, when compared to the USEPA’s criterion for cancer risk was below the level of risk.
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