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Malathion-induced hepatotoxicity in male Wistar rats: biochemical and histopathological studies Full text
2015
Flehi-Slim, Imen | Chargui, Issam | Boughattas, Sonia | El Mabrouk, Aymen | Belaïd-Nouira, Yosra | Neffati, Fadwa | Najjar, Mohamed Fadhel | Haouas, Zohra | Cheikh, Hassen Ben
The increasing use of organophosphorus pesticides in the environment constitutes an ecotoxicological hazard especially for humans and non-target animals. Hereby, we analyzed the toxic effects of malathion on the histological structure of liver and biochemical parameters in male rats. Three groups received daily different amounts of malathion: 1/1000, 1/100, and 1/10 LD₅₀ for 30 days. The weights of treated rat’s liver have increased. Analyzed tissues showed centrilobular and sinusoidal congestion, hepatocyte hypertrophy, cellular vacuolization, anucleated hepatocytes, depletion of organelles affecting the majority of cells, and presence of necrotic foci into the hepatic parenchyma. Histological sections of the liver showed important hepatocyte glycogen storage. We conclude that malathion stimulates the filing of glycogen in a dose-dependent manner. Biochemical parameters showed that alanine transaminase (ALT), aspartate transaminase (AST), gamma glutamyl transpeptidase (GGT), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP) levels increased in the treated groups when the level of total protein decreased in intoxicated groups.
Show more [+] Less [-]Concomitant evaluation of atmospheric levels of polychlorinated biphenyls, organochlorine pesticides, and polycyclic aromatic hydrocarbons in Strasbourg (France) using pine needle passive samplers Full text
2015
Al Dine, Enaam Jamal | Mokbel, Haifaa | Elmoll, Ahmad | Massemin, Sylvie | Vuilleumier, Stéphane | Toufaily, Joumana | Hanieh, Tayssir | Millet, Maurice
In this study, pine needles were used as cost-effective and reliable passive bio-monitors to concomitantly evaluate atmospheric concentrations of three classes of persistent organic pollutants, polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polycyclic aromatic hydrocarbons (PAHs). The extraction of persistent organic pollutants (POPs) from needle samples was performed. Eleven PCBs, 11 OCPs, and 15 PAHs were detected and followed through time in needle samples from three sites in the Strasbourg region. The urban and rural sites were more exposed to PCBs than the suburban site. The highest concentration of PCBs was found at the urban site, but the largest number of congeners (10) was detected at the rural site. PCB 189 and 156 were the predominant congeners in the rural site and PCB 70 in the urban site. For OCPs, the rural site displayed the highest concentrations (up to 22.9 ng g⁻¹) and number of compounds investigated (9). The high concentration of γ- and β-hexachlorocyclohexane (HCH) at that time in the urban site was the reason for this result. γ- and β-HCH were the two predominant compounds in all samples. The suburban and urban sites were the most exposed with PAHs with pyrene, phenanthrene, and acenaphthene being the three predominant compounds in these sites. No specific trend in terms of time was apparent for PCBs and OCPs. However, higher concentrations were detected for some compounds in the first sampling, especially for PAHs, and this is attributed to variations in meteorological conditions (e.g., temperature, wind, rain) and variable inputs from both identified and unidentified sources.
Show more [+] Less [-]Metal partitioning in plant–substrate–water compartments under EDDS-assisted phytoextraction of pyrite waste with Brassica carinata A. Braun Full text
2015
Vamerali, T. | Bandiera, M. | Lucchini, P. | Mosca, G.
Soil amendment with chelating agents can increase metal uptake and translocation in biomass species through increased metal bioavailability together with possible increases in metal leaching. In this study, we assessed the efficiency and environmental risk of the fast-degradable [S,S]-EDDS. Cu, Pb and Zn uptake in pot-cultivated Brassica carinata A. Braun, residual substrate metal bioavailability and leaching were investigated after one cycle of EDDS-assisted phytoextraction in mixed metal-contaminated pyrite waste, which is characterised by high Fe content. The chelator was supplied at doses of 2.5 and 5 mmol EDDS kg⁻¹waste 1 week before harvest and 1 mmol EDDS kg⁻¹waste repeated five times at 5- and 10-day intervals during the growing cycle. Here we demonstrate that EDDS generally increases shoot metal concentrations—especially of Cu—but only seldom improves removals because of markedly impaired growth. Considerable phytotoxicity and Cu leaching occurred under repeated EDDS treatments, although environmental risks may also arise from the single, close-to-harvest applications as Cu bioavailability in waste at plant harvest still remained very high (up to +67 % at 5 mmol EDDS kg⁻¹vs. untreated controls). The residual bioavailability of Zn and Pb was instead generally reduced, perhaps due to shifts in cation exchange, whereas Fe mobility was not apparently affected. The amount of metals removed by plants represented a small fraction of the bioavailable pool (<1 %), and mobilised metals quickly reached deep layers in the substrate. We conclude that EDDS assistance can provide only some limited opportunities for improving phytoremediation of pyrite waste, major benefits being achieved by low doses to be traditionally applied shortly before harvest, with due attention to limiting groundwater pollution.
Show more [+] Less [-]Methods for assessing the energy-saving efficiency of industrial symbiosis in industrial parks Full text
2015
Li, Wenfeng | Cui, Zhaojie | Han, Feng
The available energy resources are being depleted worldwide. Industrial symbiosis (IS) provides a promising approach for increasing the efficiency of energy utilization, with numerous studies reporting the superiority of this technology. However, studies quantifying the energy-saving efficiency of IS remain insufficient. This paper proposes an index system for the quantitative evaluation of the energy-saving efficiency of IS. Both energy-saving and financial indexes were selected, the former include the IS energy-saving index, the contribution rate of energy saved through IS, fractional energy savings, and cut rate of energy consumption per total output value; and the latter include the IS investment payback period, IS input–output ratio, net present value (NPV), and internal rate of return (IRR) of IS. The proposed methods were applied to a case study on the XF Industrial Park (XF IP), in the city of Liaocheng in Shandong Province of China. Three energy-saving channels using IS were found in the XF IP: (a) utilizing the energy of high-temperature materials among industrial processes, (b) recovering waste heat and steam between different processes, and (c) saving energy by sharing infrastructures. The results showed that the energy efficiency index of IS was 0.326, accounting for 34.6 % of the comprehensive energy-saving index in 2011, and the fractional energy-savings were 12.42 %. The index of energy consumption per total industrial output value varied from 90.9 tce/MRMB to 51.6 tce/MRMB. Thus, the cut rate of energy consumption per total industrial output value was 43.42 %. The average values of the IS input–output ratio was 406.2 RMB/tce, 57.2 % lower than the price of standard coal. Static investment payback period in the XF IP was 8.5 months, indicating that the XF IP began to earn profit 8.5 months after the construction of all IS modes. The NVP and IRR of each IS mode in the XF IP were greater than zero, with average values equal to 1,789.96 MRMB and 140.96 %, respectively. The computation result for each indicator revealed that IS could lead to the use of energy with high efficiency and lighten the financial burden of enterprises in the XF IP. And the proposed index system may help IPs and EIPs to make strategic decisions when designing IS modes.
Show more [+] Less [-]Statistical, time series, and fractal analysis of full stretch of river Yamuna (India) for water quality management [Erratum: Oct. 2020, v.27(33), pp.42189-42191] Full text
2015
Parmar, Kulwinder Singh | Bhardwaj, Rashmi
River water is a major resource of drinking water on earth. Management of river water is highly needed for surviving. Yamuna is the main river of India, and monthly variation of water quality of river Yamuna, using statistical methods have been compared at different sites for each water parameters. Regression, correlation coefficient, autoregressive integrated moving average (ARIMA), box-Jenkins, residual autocorrelation function (ACF), residual partial autocorrelation function (PACF), lag, fractal, Hurst exponent, and predictability index have been estimated to analyze trend and prediction of water quality. Predictive model is useful at 95 % confidence limits and all water parameters reveal platykurtic curve. Brownian motion (true random walk) behavior exists at different sites for BOD, AMM, and total Kjeldahl nitrogen (TKN). Quality of Yamuna River water at Hathnikund is good, declines at Nizamuddin, Mazawali, Agra D/S, and regains good quality again at Juhikha. For all sites, almost all parameters except potential of hydrogen (pH), water temperature (WT) crosses the prescribed limits of World Health Organization (WHO)/United States Environmental Protection Agency (EPA).
Show more [+] Less [-]Formation and removal of dissolved organic nitrogen (DON) in membrane bioreactor and conventional activated sludge processes Full text
2015
Han, Xiaomeng | Wang, Zhiwei | Ma, Jinxing | Zheng, Junjian | Wang, Pan | Wu, Zhichao
Dissolved organic nitrogen (DON) has become a growing concern due to its contribution to eutrophication and nitrogenous disinfection byproducts (N-DBPs) formation. However, information of DON in membrane bioreactors (MBRs) is very limited. In this study, occurrence, transformation and fate of DON in an MBR system were systematically investigated. MBR sludge showed a larger hydrolysis rate of particle organic nitrogen (PON) and also a higher transformation rate of DON to nitrate compared to conventional activated sludge (CAS). For long-term experiments, MBR achieved higher DON removal efficiency at low temperature than CAS; however, at high temperature, the effluent DON concentrations were almost the same in both systems. Batch tests on DON biodegradability showed that DON concentration increased and large molecular weight DON accumulated after 3-h aeration at low temperature, while DON concentration continuously decreased with the increase of aeration time at high temperature. The obtained results provide insights in DON removal in MBRs for meeting increasingly stringent regulations in terms of nitrogen removal.
Show more [+] Less [-]DNA-protein cross-links involved in growth inhibition of rice seedlings exposed to Ga Full text
2015
Yu, Xiao-Zhang | Zhang, Xue-Hong
Hydroponic experiments were conducted with rice seedlings (Oryza sativa L. cv. XZX45) exposed to gallium nitrate (Ga³⁺) to investigate the accumulation of Ga in plant tissues and phytotoxic responses. Results showed that phyto-transport of Ga was apparent, and roots were the dominant site for Ga accumulation. The total accumulation rates of Ga responded biphasically to Ga treatments by showing increases at low (1.06–8.52 mg Ga/L) and constants at high (8.52–15.63 mg Ga/L) concentrations, suggesting that accumulation kinetics of Ga followed a typical saturation curve. Higher amount of Ga accumulation in plant tissues led to significant inhibition in relative growth rate and water use efficiency in a dose-dependent manner. DNA-protein cross-links (DPCs) analysis revealed that overaccumulation of Ga in plant tissues positively stimulated formation of DPCs in roots. Likewise, the measure of root cell viability evaluated by Evan blue uptake showed a similar trend. These results suggested that Ga can be absorbed, transported, and accumulated in plant materials of rice seedlings. Overaccumulation of Ga in plant tissues provoked the formation of DPCs in roots, which resulted in cell death and growth inhibition of rice seedlings.
Show more [+] Less [-]Integron diversity in marine environments Full text
2015
Abella, Justine | Bielen, Ana | Huang, Lionel | Delmont, Tom O. | Vujaklija, Dušica | Duran, Robert | Cagnon, Christine
Integrons are bacterial genetic elements known to be active vectors of antibiotic resistance among clinical bacteria. They are also found in bacterial communities from natural environments. Although integrons have become especially efficient for bacterial adaptation in the particular context of antibiotic usage, their role in natural environments in other contexts is still unknown. Indeed, most studies have focused on integrons and the spread of antibiotic resistance in freshwater or soil impacted by anthropogenic activities, with only few on marine environments. Notably, integrons show a wider diversity of both gene cassettes and integrase gene in natural environments than in clinical environments, suggesting a general role of integrons in bacterial adaptation. This article reviews the current knowledge on integrons in marine environments. We also present conclusions of our studies on polluted and nonpolluted backgrounds.
Show more [+] Less [-]Cr(VI) and COD removal from landfill leachate by polyculture constructed wetland at a pilot scale Full text
2015
Madera-Parra, C. A. | Peña, M. R. | Peña, E. J. | Lens, P. N. L.
Four subsurface horizontal-flow constructed wetlands (CWs) at a pilot scale planted with a polyculture of the tropical plants Gynerium sagittatum (Gs), Colocasia esculenta (Ce) and Heliconia psittacorum (He) were evaluated for 7 months. The CW cells with an area of 17.94 m² and 0.60 m (h) each and 0.5 m of gravel were operated at continuous gravity flow (Q = 0.5 m³ day⁻¹) and a theoretical HRT of 7 days each and treating landfill leachate for the removal of filtered chemical oxygen demand (CODf), BOD₅, TKN, NH₄ ⁺, NO₃ ⁻, PO₄ ³⁻–P and Cr(VI). Three CWs were divided into three sections, and each section (5.98 m²) was seeded with 36 cuttings of each species (plant density of six cuttings per square metre). The other unit was planted randomly. The final distributions of plants in the bioreactors were as follows: CW I (He-Ce-Gs), CW II (randomly), CW III (Ce-Gs-He) and CW IV (Gs-He-Ce). The units received effluent from a high-rate anaerobic pond (BLAAT®). The results show a slightly alkaline and anoxic environment in the solid-liquid matrix (pH = 8.0; 0.5–2 mg L⁻¹ dissolved oxygen (DO)). CODf removal was 67 %, BOD₅ 80 %, and TKN and NH₄ ⁺ 50–57 %; NO₃ ⁻ effluents were slightly higher than the influent, PO₄ ³⁻–P (38 %) and Cr(VI) between 50 and 58 %. CW IV gave the best performance, indicating that plant distribution may affect the removal capacity of the bioreactors. He and Gs were the plants exhibiting a translocation factor (TF) of Cr(VI) >1. The evaluated plants demonstrated their suitability for phytoremediation of landfill leachate, and all of them can be categorized as Cr(VI) accumulators. The CWs also showed that they could be a low-cost operation as a secondary system for treatment of intermediated landfill leachate (LL).
Show more [+] Less [-]Response of extracellular carboxylic and thiol ligands (oxalate, thiol compounds) to Pb2+ stress in Phanerochaete chrysosporium Full text
2015
Li, Ningjie | Zeng, Guangming | Huang, Danlian | Huang, Chao | Lai, Cui | Wei, Chen | Xu, Piao | Zhang, Chen | Cheng, Min | Yan, Ming
When exposed to higher Pb²⁺ concentration, Phanerochaete chrysosporium secreted higher content of oxalate and thiol compounds. An earlier and faster increase in oxalate was observed after short-term exposure, comparing with a gentle increase in the thiol compounds. In the extracellular polymeric substances (EPS) extract, more oxalate and T-SH were detected when the initial Pb²⁺ was higher, and the variations were different from the situation in the culture medium. In EPS solution, the oxalate amount was more closely related with Pb than that of thiol compounds. pH condition in the whole Pb removal process by P. chrysosporium ranged from 4 to 6.5 and was more beneficial for the binding of Pb²⁺ to carboxylic groups in the oxalic acid. More Pb²⁺ induced more EPS amount, and the increase of EPS amount influenced the immobilized oxalate more seriously. The present study can supply more comprehensive information about the metal passivation mechanism in white-rot fungi and provide meaningful references for an enhanced removal of heavy metals.
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