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Spatial and temporal distribution of polycyclic aromatic hydrocarbons (PAHs) in surface water from Liaohe River Basin, northeast China 全文
2014
Lv, Jiapei | Xu, Jian | Guo, Changsheng | Zhang, Yuan | Bai, Yangwei | Meng, Wei
Liaohe River Basin is an important region in northeast China, which consists of several main rivers including Liao River, Taizi river, Daliao River, and Hun River. As a highly industrialized region, the basin receives dense waste discharges, causing severe environmental problems. In this study, the spatial and temporal distribution of aqueous polycyclic aromatic hydrocarbons (PAHs) in Liaohe River Basin from 50 sampling sites in both dry (May) and level (October) periods in 2012 was investigated. Sixteen USEPA priority PAHs were quantified by gas chromatography/mass selective detector. The total PAH concentration ranged from 111.8 to 2,931.6 ng/L in the dry period and from 94.8 to 2766.0 ng/L in the level period, respectively. As for the spatial distribution, the mean concentration of PAHs followed the order of Taizi River > Daliao River > Hun River > Liao River, showing higher concentrations close to large cities with dense industries. The composition and possible sources of PAHs in the water samples were also determined. The fractions of low molecular weight PAHs ranged from 58.2 to 93.3 %, indicating the influence of low or moderate temperature combustion process. Diagnostic ratios, principal component analysis, and hierarchical cluster analysis were used to study the possible source categories in the study area, and consistent results were obtained from different techniques, that PAHs in water samples mainly originated from complex sources, i.e., both pyrogenic and petrogenic sources. The benzo[a]pyrene equivalents (EBaP) characterizing the ecological risk of PAHs to the aquatic environment suggested that PAHs in Liaohe River Basin had already caused environmental health risks.
显示更多 [+] 显示较少 [-]Green synthesis of silver nanoparticles by microorganism using organic pollutant: its antimicrobial and catalytic application 全文
2014
Otari, S. V. | Patil, R. M. | Nadaf, N. H. | Ghosh, S. J. | Pawar, S. H.
A novel approach for the green synthesis of silver nanoparticles (AgNPs) from aqueous solution of AgNO₃using culture supernatant of phenol degraded broth is reported in this work. The synthesis was observed within 10 h, and AgNPs showed characteristic surface plasmon resonance around 410 nm. Spherical nanoparticles of size less than 30 nm were observed in transmission electron microscopy. X-ray diffraction pattern corresponding to 111, 200, 220, and 311 revealed the crystalline nature of the as-formed nanoparticles. It was found that the colloidal solution of AgNP suspensions exhibited excellent stability over a wide range of ionic strength, pH, and temperature. The effect of pH and ionic strength indicated that stabilization is due to electrostatic repulsion arising from the negative charge of the conjugate proteins. The AgNPs showed highly potent antimicrobial activity against Gram-positive, Gram-negative, and fungal microorganisms. The as-prepared AgNPs showed excellent catalytic activity in reduction of 4-nitrophenol to 4-aminophenol by NaBH₄. By manufacturing magnetic alginate beads, the reusability of the AgNPs for the catalytic reaction has been demonstrated.
显示更多 [+] 显示较少 [-]Effect of Zn toxicity on root morphology, ultrastructure, and the ability to accumulate Zn in Moso bamboo (Phyllostachys pubescens) 全文
2014
Liu, Dan | Chen, Junren | Mahmood, Qaisar | Li, Song | Wu, Jiasen | Ye, Zhengqian | Peng, Danli | Yan, Wenbo | Lu, Kouping
The effects of zinc (Zn) on seed germination and growth of Moso bamboo (Phyllostachys pubescens) were investigated. Under zinc stress, the seed germination rate did not show significant difference from that of the control. Hydroponics experiments indicated that Moso bamboo had a strong ability to accumulate Zn in the shoot and it reached its maximum value in the shoot at 100 μM Zn. The root Zn concentration ranged from 2,329.29 to 8,642.51 mg kg⁻¹, with the root Zn concentration at 10 μM Zn being 58.23 times that of the control. The root morphology parameters slightly increased at the lower Zn treatments, while growth restriction was evident at higher Zn treatments. Root ultrastructural studies revealed that the cell structure, root tips, and organelles were significantly changed under Zn stress as compared to those of the control. Some abnormalities were evident in the cell walls, vacuoles, mitochondria, plasmalemma, tonoplast, and xylem parenchyma of root cells. While Moso bamboo seems a suitable candidate for phytoremediation, its metal remediation ability should be further explored in future investigations.
显示更多 [+] 显示较少 [-]Isotherm studies for the determination of Cd (II) ions removal capacity in living biomass of a microalga with high tolerance to cadmium toxicity 全文
2014
Torres, Enrique | Mera, Roi | Herrero, Concepción | Abalde Alonso, Julio
Isotherm studies for the determination of Cd (II) ions removal capacity in living biomass of a microalga with high tolerance to cadmium toxicity 全文
2014
Torres, Enrique | Mera, Roi | Herrero, Concepción | Abalde Alonso, Julio
The biosorption characteristics of Cd (II) ions using the living biomass of the marine diatom Phaeodactylum tricornutum were investigated. This microalga is a highly tolerant species to cadmium toxicity; for this reason, it is interesting to know its potential for use in the removal of this metal. The use of living biomass offers better possibilities than that of dead biomass since cadmium can also be bioaccumulated inside the cells. For this purpose, tolerant species are necessary. P. tricornutum is within this category with an EC₅₀,₉₆ₕof 19.1 ± 3.5 mg Cd (II)/L, and in the present manuscript, it is demonstrated that this microalga has a very good potential for bioremediation of Cd (II) ions in saline habitats. Cadmium removed by the cells was divided into three fractions: total, intracellular and bioadsorbed. The experiments were conducted for 96 h in natural seawater with a concentration range of 1–100 mg Cd (II)/L. Each fraction was characterized every 24 h by sorption isotherms. The experimental isotherm data were analyzed using the Langmuir, Freundlich, Dubinin-Radushkevich and Temkin equations. The biosorption was well described by Langmuir isotherm followed by Freundlich. The worst model was Temkin. The biosorption capacity of this microalga for Cd (II) ions was found to be 67.1 ± 3.2 mg/g after 96 h with approximately 40 % of this capacity in the intracellular fraction. The bioconcentration factor determined was 2,204.7 after 96 h and with an initial Cd (II) concentration of 1 mg/L.
显示更多 [+] 显示较少 [-]Isotherm studies for the determination of Cd(II) ions removal capacity in living biomass of a microalga with high tolerance to cadmium toxicity. 全文
2014
Torres, Enrique | Mera, Roi | Herrero, Concepción | Abalde, Julio
The biosorption characteristics of Cd(II) ions using the living biomass of the marine diatom Phaeodactylum tricornutum were investigated. This microalga is a highly tolerant species to cadmium toxicity, for this reason is interesting to know its potential for use in the removal of Cd(II) ions. The use of living biomass offers better possibilities than dead biomass since cadmium can also be bioaccumulated inside the cells. For this purpose, tolerant species are necessary. P. tricornutum is within this category and in the present manuscript is demonstrated that this microalga has a very good potential for bioremediation of Cd(II) ions. Cadmium removed by the cells was divided into three fractions: total, intracellular and bioadsorbed. The experiments were conducted for 96 h in a concentration range of 1-100 mg Cd(II)/L. Each fraction was characterized every 24 h by sorption isotherms. The experimental isotherm data were analysed using the Langmuir, Freundlinch, Dubinin-Radushkevich and Temkin equations. The biosorption was well described by Langmuir isotherm followed by Freundlich. The worst model was Temkin. The biosorption capacity of this microalga for Cd(II) ions was found to be 67.140 ± 3.247 mg/g after 96 h with approximately 40% of this capacity in the intracellular fraction. The bioconcentration factor determined was 2204.7 after 96 h and with an initial Cd(II) concentration of 1 mg/L.
显示更多 [+] 显示较少 [-]Adsorption and desorption of 2,4,6-trichlorophenol onto and from ash as affected by Ag⁺, Zn ²⁺, and Al ³⁺ 全文
2014
Chen, Guangcai | Wang, Yusheng | Pei, Zhiguo
Metal cations and organic pollutants mostly co-exist in the natural environment. However, their interactions in adsorption processes have yet to be adequately addressed. In the current study, the effect of inorganic cations with different charges (Ag⁺, Zn²⁺, and Al³⁺) on the adsorption and desorption of 2,4,6-trichlorophenol (TCP) onto and from processed ash derived from wheat (Triticum aestivum L.) straw was investigated. The adsorption and desorption of TCP were both nonlinear; the isotherm and kinetics curves fitted well using the Freundlich equation and a pseudo-second-order model, respectively. The presence of Ag⁺ promoted TCP adsorption, while Zn²⁺ and Al³⁺ reduced TCP adsorption onto ash. The desorption of TCP from ash showed obvious hysteresis, and the presence of Ag⁺, Zn²⁺, and Al³⁺ caused the desorption to be less hysteretic. The suppression of TCP adsorption by Zn²⁺ and Al³⁺ was ascribed to the partial overlapping of adsorption groups between TCP and metal ions. Al³⁺ had a stronger inhibition effect than that of Zn²⁺ due to its higher binding capacity and larger hydrated ionic radius than those of Zn²⁺. Enhanced adsorption of TCP onto ash by Ag⁺ was ascribed to its ability to reduce the competitive adsorption of water molecules on ash surface by replacing the original ions, such as Na⁺ and Ca²⁺, and compressing the hydrated ionic radius of these metal ions. In addition, Ag⁺ was able to bind with the aromatic organic compounds containing π-electrons, which resulted in a further increase of TCP adsorption by ash.
显示更多 [+] 显示较少 [-]Assessment of sewage sludge bioremediation at different hydraulic retention times using mixed fungal inoculation by liquid-state bioconversion 全文
2014
Rahman, Roshanida A. | Molla, Abul Hossain | Fakhru’l-Razi, A.
Sustainable, environmental friendly, and safe disposal of sewage treatment plant (STP) sludge is a global expectation. Bioremediation performance was examined at different hydraulic retention times (HRT) in 3–10 days and organic loading rates (OLR) at 0.66–7.81 g chemical oxygen demand (COD) per liter per day, with mixed filamentous fungal (Aspergillus niger and Penicillium corylophilum) inoculation by liquid-state bioconversion (LSB) technique as a continuous process in large-scale bioreactor. Encouraging results were monitored in treated sludge by LSB continuous process. The highest removal of total suspended solid (TSS), turbidity, and COD were achieved at 98, 99, and 93 %, respectively, at 10 days HRT compared to control. The minimum volatile suspended solid/suspended solid implies the quality of water, which was recorded 0.59 at 10 days and 0.72 at 3 days of HRT. In treated supernatant with 88 % protein removal at 10 days of HRT indicates a higher magnitude of purification of treated sludge. The specific resistance to filtration (SRF) quantifies the performance of dewaterability; it was recorded minimum 0.049 × 10¹² m kg⁻¹at 10 days of HRT, which was equivalent to 97 % decrease of SRF. The lower OLR and higher HRT directly influenced the bioremediation and dewaterability of STP sludge in LSB process. The obtained findings imply encouraging message in continuing treatment of STP sludge, i.e., bioremediation of wastewater for environmental friendly disposal in near future.
显示更多 [+] 显示较少 [-]Reproductive toxicity of lead, cadmium, and phthalate exposure in men 全文
2014
Pant, Niraj | Kumar, G. | Upadhyay, A. D. | Patel, D. K. | Gupta, Y. K. | Chaturvedi, P. K.
Environmental toxicants viz lead or cadmium and phthalate esters (di(2-ethylhexyl) phthalate [DEHP], dibutyl phthalate [DBP], and diethyl phthalate [DEP]) widely found in different environmental strata are linked to deteriorating male reproductive health. The objective was to assess the relationships between the seminal lead, cadmium, and phthalate (DEHP, DBP, DEP) concentrations at environmental level and serum hormone levels and semen quality in non-occupationally exposed men and specify the effect of individual and combined exposure of toxicants on semen quality. A study of 60 male partners of couples attending the Andrology Laboratory of the Reproductive Biology Department, All India Institute of Medical Sciences (AIIMS), New Delhi, India for semen analysis to assess their inability to achieve a pregnancy was selected for the study. The results of univariate and stepwise multiple regression analysis in the unadjusted model showed a significant correlation between lead or cadmium and phthalates DEHP/DBP/DEP and sperm motility, sperm concentration, and DNA damage. After adjusting for potential confounders, an association with lead or DEHP was only observed. The present data shows that lead (Pb) or cadmium (Cd) or phthalates might independently contribute to decline in semen quality and induce DNA damage. Phthalates might influence reproductive hormone testosterone. These findings are significant in light of the fact that men are exposed to a volley of chemicals; however, due to the small sample size, our finding needs to be confirmed in a larger population.
显示更多 [+] 显示较少 [-]A short-term study to evaluate the uptake and accumulation of arsenic in Asian willow (Salix sp.) from arsenic-contaminated water 全文
2014
Chen, Guangcai | Zou, Xiaoli | Zhou, Yuan | Zhang, Jianfeng | Owens, Gary
Five Asian willow species (Salix jiangsuensis J172, Salix matsudana, Salix integra Yizhibi, Salix integra Weishanhu, and Salix mongolica) were evaluated for their potential for phytofiltration of arsenic (As) from synthetically contaminated waters. Arsenic accumulation, tolerance, uptake influx, and phytofiltration ability of the five willow species were examined under hydroponic conditions in a glasshouse. Short-term exposure (2 weeks) to solutions containing 80 μmol L⁻¹arsenate (As(V)), resulted in significant accumulation of As in all willow species. Arsenic concentration in plant roots ranged from 322 mg kg⁻¹dry weight (DW) for S. matsudana to 604 mg kg⁻¹(DW) for S. integra Yizhibi. S. integra Yizhibi decreased As(V) concentration in water from 3.87 to 1.89 μmol L⁻¹(290 to 142 μg L⁻¹) over 168 h, which is 50 % of the total As(V) in the solution. The results suggested that even though Asian willow was not a traditional aquatic species, it still had significant potential for phytofiltration of As from contaminated waters. Of the five willow species studied, S. integra Yizhibi had the greatest capacity to remove As from As-contaminated waters. Thus, Asian willow has significant potential for the phytofiltration of As and may also be suitable for practical phytoremediation of As in highly water-logged areas.
显示更多 [+] 显示较少 [-]Perfluoroalkyl acids in blood serum samples from children in Taiwan 全文
2014
Bao, Jia | Lee, Yungling Leo | Chen, Pau-Chung | Jin, Yi-He | Dong, Guang-Hui
Severe perfluoroalkyl acid (PFAA) contamination resulting from the fast-growing semiconductor, electrochemical, and optoelectronic industries has been determined in the river water in the vicinity of the Taipei area, Taiwan, during recent years. However, little is known about body burdens of the PFAA contaminations in local residents, especially children living in the Taipei area recently. In this study, ten target PFAA analytes consisted of three perfluorosulfonates (PFSAs) and seven perfluorocarboxylates (PFCAs) in the blood serum samples, collected from 225 healthy children with an average age of 13.6 years in the Taipei area from 2009 to 2010, were analyzed via high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS). As the dominant PFAA contaminant in the blood serum samples from Taiwanese children, perfluorooctane sulfonate (PFOS) contributed 86 % of all the target PFAA analytes, while the other nine analytes contributed less than 5 % individually. PFOS showed the highest median up to 29 ng/mL, ranging from 0.03 to 148 ng/mL, which was higher than that observed in the serum samples collected from Taiwanese children between 2006 and 2008. Statistically, serum concentrations of perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), and perfluorooctanoic acid (PFOA) had significantly positive correlations with ages of children (p < 0.05). Furthermore, serum PFBS, PFHxS, and PFOA concentrations in the male children were considerably higher than those in the female children (p = 0.049, p = 0.000, p = 0.000).
显示更多 [+] 显示较少 [-]Ant cuticular response to phthalate pollution 全文
2014
Lenoir, Alain | Touchard, Axel | Devers, Séverine | Christidès, Jean-Philippe | Boulay, Raphaël | Cuvillier-Hot, Virginie
Ant cuticular response to phthalate pollution 全文
2014
Lenoir, Alain | Touchard, Axel | Devers, Séverine | Christidès, Jean-Philippe | Boulay, Raphaël | Cuvillier-Hot, Virginie
Phthalates are common atmospheric contaminants used in the plastic industry. Ants have been shown to constitute good bioindicators of phthalate pollution. Hence, phthalates remain trapped on ant cuticles which are mostly coated with long-chain hydrocarbons. In this study, we artificially contaminated Lasius niger ants with four phthalates: dibutyl phthalate (DBP), diisobutyl phthalate (DiBP), di(2-ethylhexyl) phthalate (DEHP), and benzyl butyl phthalate (BBP). The first three have previously been found on ants in nature in Touraine (France), while the fourth has not. The four phthalates disappeared rapidly (less than 5 days) from the cuticles of live ants. In contrast, on the cuticles of dead ants, DEHP quantities remained unchanged over time. These results indicate that phthalates are actively absorbed by the cuticles of live ants. Cuticular absorption of phthalates is nonspecific because eicosane, a nonnatural hydrocarbon on L. niger cuticle, was similarly absorbed. Ants are important ecological engineers and may serve as bioindicators of ecosystem health. We also suggest that ants and more generally terrestrial arthropods may contribute to the removal of phthalates from the local environment.
显示更多 [+] 显示较少 [-]Ant cuticular response to phthalate pollution 全文
2014
Lenoir, Alain | Touchard, Axel | Devers, Séverine | Christidès, Jean-Philippe | Boulay, Raphaël | Cuvillier-Hot, Virginie | Institut de recherche sur la biologie de l'insecte (IRBI) ; Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS) | Ecologie des forêts de Guyane (ECOFOG) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université des Antilles et de la Guyane (UAG)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS) | Génétique et évolution des populations végétales (GEPV) ; Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS)
International audience | Phthalates are common atmospheric contaminantsused in the plastic industry. Ants have been shown to constitutegood bioindicators of phthalate pollution. Hence,phthalates remain trapped on ant cuticles which are mostlycoated with long-chain hydrocarbons. In this study, we artificiallycontaminated Lasius niger ants with four phthalates:dibutyl phthalate (DBP), diisobutyl phthalate (DiBP), di(2-ethylhexyl) phthalate (DEHP), and benzyl butyl phthalate(BBP). The first three have previously been found on ants innature in Touraine (France), while the fourth has not. The fourphthalates disappeared rapidly (less than 5 days) from thecuticles of live ants. In contrast, on the cuticles of dead ants,DEHP quantities remained unchanged over time. These resultsindicate that phthalates are actively absorbed by thecuticles of live ants. Cuticular absorption of phthalates isnonspecific because eicosane, a nonnatural hydrocarbon onL. niger cuticle, was similarly absorbed. Ants are importantecological engineers and may serve as bioindicators of ecosystemhealth. We also suggest that ants and more generallyterrestrial arthropods may contribute to the removal ofphthalates from the local environment
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