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Transformation of four silver/silver chloride nanoparticles during anaerobic treatment of wastewater and post-processing of sewage sludge Full text
2013
Lombi, Enzo | Donner, Erica | Taheri, Shima | Tavakkoli, Ehsan | Jämting, Åsa K. | McClure, Stuart | Naidu, R. | Miller, Bradley W. | Scheckel, Kirk G. | Vasilev, Krasimir
Transformation of four silver/silver chloride nanoparticles during anaerobic treatment of wastewater and post-processing of sewage sludge Full text
2013
Lombi, Enzo | Donner, Erica | Taheri, Shima | Tavakkoli, Ehsan | Jämting, Åsa K. | McClure, Stuart | Naidu, R. | Miller, Bradley W. | Scheckel, Kirk G. | Vasilev, Krasimir
The increasing use of silver (Ag) nanoparticles [containing either elemental Ag (Ag-NPs) or AgCl (AgCl-NPs)] in commercial products such as textiles will most likely result in these materials reaching wastewater treatment plants. Previous studies indicate that a conversion of Ag-NPs to Ag2S is to be expected during wastewater transport/treatment. However, the influence of surface functionality, the nature of the core structure and the effect of post-processing on Ag speciation in sewage sludge/biosolids has not been investigated. This study aims at closing these knowledge gaps using bench scale anaerobic digesters spiked with Ag nitrate, three different types of Ag-NPs, and AgCl-NPs at environmentally realistic concentrations. The results indicate that neither surface functionality nor the different compositions of the NP prevented the formation of Ag2S. Silver sulfides, unlike the sulfides of other metals present in sewage sludge, were stable over a six month period simulating composting/stockpiling.
Show more [+] Less [-]Transformation of four silver/silver chloride nanoparticles during anaerobic treatment of wastewater and post-processing of sewage sludge Full text
2013
Lombi, E. | Donner, E. | Taheri, S. | Tavakkoli, E. | Jämting, A. | McClure, S. | Naidu, R. | Miller, B. | Scheckel, K. | Vasilev, K.
Abstract not available. | Enzo Lombi, Erica Donner, Shima Taheri, Ehsan Tavakkoli, Åsa K. Jämting, Stuart McClure, Ravi Naidu, Bradley W. Miller, Kirk G. Scheckel, Krasimir Vasilev
Show more [+] Less [-]Contribution of a submerged membrane bioreactor in the treatment of synthetic effluent contaminated by Bisphenol-A: Mechanism of BPA removal and membrane fouling Full text
2013
Seyhi, Brahima | Drogui, Patrick | Buelna, Gerardo | Azaïs, Antonin | Heran, Marc
A submerged membrane bioreactor has been operated at the laboratory scale for the treatment of a synthetic effluent containing Bisphenol-A (BPA). COD, NH4–N, PO4–P and BPA were eliminated respectively, at 99%, 99%, 61% and 99%. The increase of volumetric loading rate from 0 to 21.6 g/m3/d did not affect the performance of the MBR system. However, the removal rate decreased rapidly when the BPA loading rate increased above 21.6 g/m3/d. The adsorption process of BPA on the biomass was very well described by Freundlich and Langmuir isotherms. Subsequently, biodegradation of BPA occurred and followed the first order kinetic reaction, with a constant rate of 1.13 ± 0.22 h−1. During treatment, membrane fouling was reversible in the first 84 h of filtration, and then became irreversible. The membrane fouling was mainly due to the accumulation of suspended solid and development of biofilm on the membrane surface.
Show more [+] Less [-]National inventory of alkylphenol ethoxylate compounds in U.S. sewage sludges and chemical fate in outdoor soil mesocosms Full text
2013
Venkatesan, Arjun K. | Halden, Rolf U.
We determined the first nationwide inventories of alkylphenol surfactants in U.S. sewage sludges (SS) using samples from the U.S. Environmental Protection Agency's 2001 national SS survey. Additionally, analysis of archived 3-year outdoor mesocosm samples served to determine chemical fates in SS-amended soil. Nonylphenol (NP) was the most abundant analyte (534 ± 192 mg/kg) in SS composites, followed by its mono- and di-ethoxylates (62.1 ± 28 and 59.5 ± 52 mg/kg, respectively). The mean annual load of NP and its ethoxylates in SS was estimated at 2408–7149 metric tonnes, of which 1204–4289 is applied on U.S. land. NP compounds showed observable loss from SS/soil mixtures (1:2), with mean half-lives ranging from 301 to 495 days. Surfactant levels in U.S. SS ten-times in excess of European regulations, substantial releases to U.S. soils, and prolonged half-lives found under field conditions, all argue for the U.S. to follow Europe's move from 20 years ago to regulate these chemicals.
Show more [+] Less [-]Ecological risk of estrogenic endocrine disrupting chemicals in sewage plant effluent and reclaimed water Full text
2013
Sun, Yan | Huang, Huang | Sun, Ying | Wang, Chao | Shi, Xiao-Lei | Hu, Hong-Ying | Kameya, Takashi | Fujie, Koichi
The long-term ecological risk of micropollutants, especially endocrine disrupting chemicals (EDCs) has threatened reclaimed water quality. In this study, estrogenic activity and ecological risk of eight typical estrogenic EDCs in effluents from sewage plants were evaluated. The estrogenic activity analysis showed that steroidal estrogens had the highest estrogenic activity (ranged from 10−1 to 103 ng-E2/L), phenolic compounds showed weaker estrogenic activity (mainly ranged from 10−3 to 10 ng-E2/L), and phthalate esters were negligible. The ecological risk of the estrogenic EDCs which was characterized by risk quotient ranged from 10−4 to 103, with an order in descending: steroids estrogens, phenolic compounds and phthalate esters. The eight estrogenic EDCs were scored and sorted based on the comparison of the estrogenic activity and the ecological risk, suggesting that 17α-ethynylestradiol (EE2), estrone (E1) and estradiol (E2) should be the priority EDCs to control in municipal sewage plants.
Show more [+] Less [-]Uptake and accumulation of four PPCP/EDCs in two leafy vegetables Full text
2013
Dodgen, L.K. | Li, J. | Parker, D. | Gan, J.J.
Many pharmaceutical and personal care products (PPCPs) and endocrine-disrupting chemicals (EDCs) are present in reclaimed water, leading to concerns of human health risks from the consumption of food crops irrigated with reclaimed water. This study evaluated the potential for plant uptake and accumulation of four commonly occurring PPCP/EDCs, i.e., bisphenol A (BPA), diclofenac sodium (DCL), naproxen (NPX), and 4-nonylphenol (NP), by lettuce (Lactuca sativa) and collards (Brassica oleracea) in hydroponic culture, using 14C-labeled compounds. In both plant species, plant accumulation followed the order of BPA > NP > DCL > NPX and accumulation in roots was much greater than in leaves and stems. Concentrations of 14C-PPCP/EDCs in plant tissues ranged from 0.22 ± 0.03 to 927 ± 213 ng/g, but nearly all 14C-residue was non-extractable. PPCP/EDCs, particularly BPA and NP, were also extensively transformed in the nutrient solution. Dietary uptake of these PPCP/EDCs by humans was predicted to be negligible.
Show more [+] Less [-]Photobleaching of lignin derived compounds from pulp mill effluents upon irradiation: The key role of receiving waters Full text
2013
Otero, Marta | Guilherme, Isabela | Santos, Eduarda B.H.
Lignin derived macromolecular compounds are the main constituents responsible for the hazardous effects of discharged effluents from the pulp and paper industry in receiving waters. It was shown by ultraviolet–visible (UV–vis) and fluorescence spectroscopies that a selective photodegradation of these structures occurred upon irradiation of fulvic acids (FA) from a kraft pulp mill effluent. Though photodegradation was not remarkably affected by the presence of the natural photosensitizer nitrate, it was inhibited under the presence of chloride. These results indicate that the fate of macromolecular organic matter from kraft pulp mill effluents may be different depending on the type of receiving waters, having a higher persistence when effluents are discharged in estuarine or marine waters than when they are discharged in fresh water.
Show more [+] Less [-]Short- and long-term temporal changes in soil concentrations of selected endocrine disrupting compounds (EDCs) following single or multiple applications of sewage sludge to pastures Full text
2013
Rhind, S.M. | Kyle, C.E. | Ruffie, H. | Calmettes, E. | Osprey, M. | Zhang, Z.L. | Hamilton, D. | McKenzie, C.
Temporal changes in soil burdens of selected endocrine disrupting compounds were determined following application to pasture of either sewage sludge or inorganic fertilizer. Soil polycyclic aromatic hydrocarbon and polychlorinated biphenyl concentrations were not altered. Changes in concentrations of diethylhexyl phthalate (DEHP) and PBDEs 47 and 99 differed with season but concentrations remained elevated for more than three weeks after application, when grazing animals are normally excluded from pasture. It is concluded that single applications of sewage sludge can increase soil concentrations of some, but not all classes of EDCs, possibly to concentrations sufficient to exert biological effects when different chemicals act in combination, but patterns of change depend on season and soil temperature. Analysis of soil from pasture subjected to repeated sludge applications, over 13 years, provided preliminary evidence of greater increases in soil burdens of all of the EDC groups measured, including all of the PBDE congeners measured.
Show more [+] Less [-]Calibration and field evaluation of polar organic chemical integrative sampler (POCIS) for monitoring pharmaceuticals in hospital wastewater Full text
2013
Bailly, Emilie | Levi, Yves | Karolak, Sara
The Polar Organic Chemical Integrative Sampler (POCIS) is a new tool for the sampling of organic pollutants in water. We tested this device for the monitoring of pharmaceuticals in hospital wastewater. After calibration, a field application was carried out in a French hospital for six pharmaceutical compounds (Atenolol, Prednisolone, Methylprednisolone, Sulfamethoxazole, Ofloxacin, Ketoprofen).POCIS were calibrated in tap water and wastewater in laboratory conditions close to relevant environmental conditions (temperature, flow velocity). Sampling rates (Rs) were determined and we observed a significant increase with flow velocity and temperature. Whatever the compound, the Rs value was lower in wastewater and the linear phase of uptake was shorter.POCIS were deployed in a hospital sewage pipe during four days and the estimated water concentrations were close to those obtained with twenty-four hour composite samples.
Show more [+] Less [-]Reduced bioaccumulation of PAHs by Lactuca satuva L. grown in contaminated soil amended with sewage sludge and sewage sludge derived biochar Full text
2013
K̲h̲ān, Sardār | Wang, Ning | Reid, Brian J. | Freddo, Alessia | Cai, Chao
The influence of sewage sludge (SS) and sewage sludge biochar (SSBC) upon biomass yield and the bioaccumulation of PAHs into lettuce plants grown in contaminated soil (∑16PAH 20.2 ± 0.9 mg kg−1) is presented. All SSBC amendments (2, 5 and 10%) and the 2% SS amendment significantly (P < 0.01) increased lettuce biomass. Both SS and SSBC amendments significantly reduced (P < 0.01) the bioaccumulation of PAHs at all application levels; with reduction in ∑16PAH concentration ranging between 41.8 and 60.3% in SS amended treatments and between 58.0 and 63.2% in SSBC amended treatments, with respect to the control. Benefits in terms of biomass production and PAHs bioaccumulation reduction were greatest where SSBC was used as a soil amendment. At high application rates (10%) SSBC reduced bioaccumulation of PAHs by between 56% and 67%, while SS reduced bioaccumulation of PAHs by less than 44%.
Show more [+] Less [-]Migration of polybrominated diphenyl ethers in biosolids-amended soil Full text
2013
Gorgy, Tamer | Li, Loretta Y. | Grace, John R. | Ikonomou, Michael G.
A field investigation was carried out to determine PBDE concentrations over a one-year period in agricultural soils onto which 80 tonnes biosolids/hectare had been applied. The PBDE concentrations increased from 80 to 300 pg/g dry weight basis to 300 × 103–600 × 103 pg/g dw due to biosolids application, and PBDEs migrated downwards to depths of at least 0.85 m. Concentrations decreased non-uniformly with depth. PBDE levels decreased exponentially in the topmost biosolids-amended soils layer, while increasing in the next underlying soil layer over the one-year period. The rate of decrease of total PBDE mass in the top 0.00–0.05 m layer was almost two orders of magnitude greater than the rates of increase in total PBDE mass in the lower layers, indicating that effects such as photodegradation and/or volatilization likely were to have been significant in the surface layer.
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