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Attenuation of phenanthrene and pyrene adsorption by sewage sludge-derived biochar in biochar-amended soils Full text
2016
Zielińska, Anna | Oleszczuk, Patryk
The aim of this study was to evaluate the effect of soils on the sorption of phenanthrene (PHE) and pyrene (PYR) by sewage sludge-derived biochars (SS-derived biochars). The SS-derived biochars were added to soils with varying properties as well as with a different degree and source of polycyclic aromatic hydrocarbons (PAHs) contamination. The biochars (BCs) were produced from sewage sludge during pyrolysis at temperatures of 500 °C (BC500) and 700 °C (BC700). The addition of biochars to the soils (5 %, w/w) increased the sorption of PHE from 8.3 to 20.3 % and PYR from 14.5 to 31.7 % by amended soil. BC700 biochar was characterized by better sorption capacity than BC500 biochar. Nevertheless, the presence of soil reduces the effectiveness of biochars in binding the compounds studied. The sorption capacity of the biochars decreased several times after they had been mixed with the soil compared to pure biochars. The study found dissolved organic carbon (DOC) and clay minerals present in the soils to have a significant effect on reducing the efficiency of PHE and PYR sorption by biochar. A greater impact of fouling was observed in the case of BC500 biochar characterized by lower porosity than BC700 biochar.
Show more [+] Less [-]Radiocaesium in Cortinarius spp. mushrooms in the regions of the Reggio Emilia in Italy and Pomerania in Poland Full text
2016
Zalewska, Tamara | Cocchi, Luigi | Falandysz, Jerzy
Activity concentrations of ¹³⁴Cs and ¹³⁷Cs have been determined in 23 species of mushrooms of the genus Cortinarius (59 individual samples) collected from the Reggio Emilia in Italy 1992–1999 and in 4 species (16 composite samples and 413 individuals) from the Pomerania region in Poland from 1996 to 2015. Across all the Cortinarius species from the Reggio Emilia, the activity concentrations were relatively high in Cortinarius alboviolaceus, Cortinarius duracinus, Cortinarius orellanus, Cortinarius rapaceus, and Cortinarius subannulatus, in which ¹³⁷Cs was at 10,000 ~ 100,000 Bq kg⁻¹ dry biomass (db) in 1994. Smaller activity concentrations were found in Cortinarius bivelus, Cortinarius bulliardii, Cortinarius cotoneus, Cortinarius largus, Cortinarius lividoviolaceus, Cortinarius purpureus, Cortinarius rufo-olivaceus, Cortinarius torvus, and Cortinarius venetus with levels at 1000 ~ 6000 Bq kg⁻¹ db from 1992 to 1994, and further in Cortinarius anserinus, Cortinarius auroturbinatus, C. largus, Cortinarius praestans, Cortinarius purpurascens, Cortinarius scaurus, Cortinarius sebaceous, Cortinarius talus, and Cortinarius variecolor with activity concentrations at 100 ~ 600 Bq kg⁻¹ db in 1994. All the data were calculated for dehydrated fungal material corrected back to the exact date samples of collection. The greatest activity concentrations of ¹³⁷Cs both in Italy (1992–1999) and Poland (1996–2010) were found in the popular Cortinarius caperatus, confirming its very high capacity of radiocaesium accumulation. Besides ¹³⁷Cs, the isotope ¹³⁴Cs was detected in some species from the Reggio Emilia. An average calculated ratio of activities of ¹³⁴Cs to ¹³⁷Cs referenced to 1986 was equal to 0.38 in mushrooms from the Reggio Emilia, and this value slightly differ from that specific for Chernobyl fallout, which was 0.54. It was calculated that ¹³⁷Cs originating from Chernobyl accident constituted about 68 % of the total activity concentration of the isotope in Reggio Emilia in 1986, while as much as 32 % of ¹³⁷Cs in mushrooms were from the global fallout from nuclear bomb testing.
Show more [+] Less [-]Occurrence and diversity of tetracycline resistance genes in the agricultural soils of South Korea Full text
2016
Kim, Song Yeob | Kuppusamy, Saranya | Kim, Jang-hwan | Yoon, Young-Eun | Kim, Kwon-Rae | Lee, Yong Bok
Reports on the occurrence and diversity of antibiotic-resistant bacteria and genes, which are considered to be emerging pollutants worldwide, have, to date, not been published on South Korean agricultural soils. This is the first study to investigate the persistence of tetracycline (oxytetracycline, tetracycline, and chlortetracycline)-resistant bacterial community and genes in natural and long-term fertilized (NPK, pig, and cattle manure composts) agricultural soils in South Korea. The results showed that oxytetracycline and chlortetracycline could be the dominant residues in animal manures; regular fertilization of manures, particularly pig manures, may be the prime cause for the spread and abundance of tetracycline resistance in South Korean agricultural soils. Both the country’s natural and agricultural soils are reservoirs of antibiotic-resistant species. Of the 113 tetracycline-resistant isolates identified (19 typical bacterial genera and 36 distinct species), approximately 40 to 99 % belonged to Gram-positive bacteria and Bacillus constituted the predominant genera. Of the 24 tet genes targeted, tetG, tetH, tetK, tetY, tetO, tetS, tetW, and tetQ were detected in all soil samples, highlighting their predominance and robust adaptability in soils. Meanwhile, it is suggested that tetC, tetE, tetZ, tetM, tetT, and tetP(B) are the common residues in pig manures, and furthermore, the treatment of soils with pig manures may wield a different impact on the tet gene resistome in agricultural soils. This study thus highlights the necessity for regulating the usage of tetracyclines in South Korean animal farming. This must be followed by proper monitoring of the subsequent usage of animal manures especially that derived from pig farms located in agricultural soils.
Show more [+] Less [-]Evaluation of an integrated constructed wetland to manage pig manure under Mediterranean climate Full text
2016
Nehmtow, Julie | Rabier, Jacques | Giguel, Raphaël | Coulomb, Bruno | Farnet, Anne Marie | Perissol, Claude | Alary, Arnaud | Laffont-Schwob, Isabelle
Pig manure is a complex mixture with excessive nutrients such as ammonium, microbial pathogens and may contain contaminants such as antibiotics. Conventional pig manure management practices caused water contamination. Sludge treatment wetland has been evaluated to determine its potential use under Mediterranean climate aiming at a parsimonious use of water and preventing water contamination, two major steps to preserve water resources in the Mediterranean Basin. Preliminary NH₄-N degradation was tested using aeration process and/or addition of commercial bacterial products. Aeration alone appeared to be sufficient to ensure nitrogen transformation of the pig manure at lab small-scale (10 L) and medium-scale (300 L). Selected plant species e.g., Carex hispida for use in the integrated constructed wetland tolerated the nitrogen content after aeration enabling their use in a treatment vertical bed.
Show more [+] Less [-]Vermicomposting of sludge from animal wastewater treatment plant mixed with cow dung or swine manure using Eisenia fetida Full text
2016
Xie, Dan | Wu, Weibing | Hao, Xiaoxia | Jiang, Dongmei | Li, Xuewei | Bai, Lin
Vermicomposting of animal wastewater treatment plant sludge (S) mixed with cow dung (CD) or swine manure (SM) employing Eisenia fetida was tested. The numbers, weights, clitellum development, and cocoon production were monitored for 60 days at a detecting interval of 15 days. The results indicated that 100 % of the sludge can be the suitable food for growth and fecundity of E. fetida, while addition of CD or SM in sludge significantly (P < 0.05) increased the worm biomass and reproduction. The sludge amended with 40 % SM can be a great medium for the growth of E. fetida, and the sludge amended with 40 % CD can be a suitable medium for the fecundity of E. fetida. The addition of CD in sludge provided a better environment for the fecundity of earthworm than SM did. Moreover, vermicomposts obtained in the study had lower pH value, lower total organic carbon (TOC), lower NH₄ ⁺-N, lower C/N ratio, higher total available phosphorous (TAP) contents, optimal stability, and maturity. NH₄ ⁺-N, pH and TAP of the initial mixtures explained high earthworm growth. The results provided the theory basic both for management of animal wastes and the production of earthworm proteins using E. fetida.
Show more [+] Less [-]A comprehensive approach to actual polychlorinated biphenyls environmental contamination Full text
2016
Risso, F. | Magherini, A. | Ottonelli, M. | Magi, E. | Lottici, S. | Maggiolo, S. | Garbarino, M. | Narizzano, R.
Worldwide polychlorinated biphenyls (PCBs) pollution is due to complex mixtures with high number of congeners, making the determination of total PCBs in the environment an open challenge. Because the bulk of PCBs production was made of Aroclor mixtures, this analysis is usually faced by the empirical mixture identification via visual inspection of the chromatogram. However, the identification reliability is questionable, as patterns in real samples are strongly affected by the frequent occurrence of more than one mixture. Our approach is based on the determination of a limited number of congeners chosen to enable objective criteria for Aroclor identification, summing up the advantages of congener-specific analysis with the ones of total PCBs determination. A quantitative relationship is established between congeners and any single mixture, or mixtures combination, leading to the identification of the actual contamination composition. The approach, due to its generality, allows the use of different sets of congeners and any technical mixture, including the non-Aroclor ones. The results confirm that PCB environmental pollution in northern Italy is based on Aroclor. Our methodology represents an important tool to understand the source and fate of the PCBs contamination.
Show more [+] Less [-]Volatile emissions during storing of green food waste under different aeration conditions Full text
2016
Agapiou, A. | Vamvakari, J. P. | Andrianopoulos, A. | Pāppā, Ā.
Controlled field experiments were carried out for monitoring the emissions of three plastic commercial household waste bins, which were adapted for studying the effect of aeration process in the evolved volatiles, during house storing of green food waste for 2 weeks, prior to collection. Three experimental scenarios were examined based on no aeration (“NA,” closed commercial waste bin), diffusion-based aeration (“DA,” closed commercial waste bin with tiny holes), and enforced aeration (“EA,” closed commercial waste bin with tiny holes and enforced aeration). The monitoring of volatile organic compounds (VOCs) emitted from organic household kitchen waste was performed using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) analysis. Portable sensors were also used for monitoring selected gases and parameters of environmental, bioprocess, and health interest (e.g., CO₂, O₂, H₂S, CH₄, NH₃, % RH, waste temperatures). VOC emissions are strongly dependent on the waste material. The most frequent VOCs identified over the storing waste, showing over 50 % appearance in all examined samples, were terpenes (e.g., di-limonene, beta-myrcene, delta-3-carene, alpha-pinene, alpha-terpinolene, linalool, etc.), sulfides (dimethyl disulfide), aromatics (benzene, 1-methyl-2-(2-propenyl)), alkanes (e.g., decane, dodecane), ketones (2-propanone), esters (e.g., acetic acid ethyl ester, acetic acid methyl ester), and alcohols (e.g., 3-cyclohexen-1-ol, 4-methyl-1-(1-methylethyl)). The prominent role of terpenes in the “pre-compost” odor and especially that of di-limonene was highlighted. In all examined scenarios, the emitted volatiles were increased at raised temperatures and later decreased in time. Aeration of waste bins slightly affected the volatilization process resulting in higher profiles of VOCs; uniformity in the composition of VOCs was also noted. Slight modifications of commercial waste bins may favor the initiation of home composting.
Show more [+] Less [-]Lethal and sub-lethal effects of elevated CO2 concentrations on marine benthic invertebrates and fish Full text
2016
Lee, Changkeun | Hong, Seongjin | Kwon, Bong-Oh | Lee, Jung-Ho | Ryu, Jongseong | Park, Young-Gyu | Kang, Seong-Gil | Khim, Jong Seong
Concern about leakage of carbon dioxide (CO₂) from deep-sea storage in geological reservoirs is increasing because of its possible adverse effects on marine organisms locally or at nearby coastal areas both in sediment and water column. In the present study, we examined how elevated CO₂ affects various intertidal epibenthic (benthic copepod), intertidal endobenthic (Manila clam and Venus clam), sub-tidal benthic (brittle starfish), and free-living (marine medaka) organisms in areas expected to be impacted by leakage. Acute lethal and sub-lethal effects were detected in the adult stage of all test organisms exposed to varying concentrations of CO₂, due to the associated decline in pH (8.3 to 5.2) during 96-h exposure. However, intertidal organisms (such as benthic copepods and clams) showed remarkable resistance to elevated CO₂, with the Venus clam being the most tolerant (LpH₅₀ = 5.45). Sub-tidal species (such as brittle starfish [LpH₅₀ = 6.16] and marine medaka [LpH₅₀ = 5.91]) were more sensitive to elevated CO₂ compared to intertidal species, possibly because they have fewer defensive capabilities. Of note, the exposure duration might regulate the degree of acute sub-lethal effects, as evidenced by the Venus clam, which showed a time-dependent effect to elevated CO₂. Finally, copper was chosen as a model toxic element to find out the synergistic or antagonistic effects between ocean acidification and metal pollution. Combination of CO₂ and Cu exposure enhances the adverse effects to organisms, generally supporting a synergistic effect scenario. Overall, the significant variation in the degree to which CO₂ adversely affected organisms (viz., working range and strength) was clearly observed, supporting the general concept of species-dependent effects of elevated CO₂.
Show more [+] Less [-]The application of catalyst-recovered SnO2 as an anode material for lithium secondary batteries Full text
2016
Ryu, Da-Jeong | Jung, Hee-Won | Lee, Sung Hun | Park, Da-Jeong | Ryu, Kwang-Sun
We studied the electrochemical characteristics of tin dioxide (SnO₂) recovered from waste catalyst material which had been previously used in a polymer synthesis reaction. In order to improve the electrochemical performance of the SnO₂ anode electrode, we synthesized a nanocomposite of recovered SnO₂ and commercial iron oxide (Fe₂O₃) (weight ratio 95:5) using a solid state method. X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) analyses revealed an additional iron oxide phase within a porous nanocomposite architecture. The electrochemical characterizations were based on galvanostatic charge–discharge (CD) curves, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). In the first discharge, the capacity of the SnO₂–Fe₂O₃ nanocomposite was 1700 mAh g⁻¹, but was reduced to about 1200 mAh g⁻¹ in the second discharge. Thereafter, a discharge capacity of about 1000 mAh g⁻¹was maintained up to the 20th cycle. The SnO₂–Fe₂O₃ nanocomposite showed better reversible capacities and rate capabilities than either the recovered SnO₂ or commercial Fe₂O₃ nanoparticle samples.
Show more [+] Less [-]Antibiotic and heavy-metal resistance of Vibrio parahaemolyticus isolated from fresh shrimps in Shanghai fish markets, China Full text
2016
He, Yu | Jin, Lanlan | Sun, Fengjiao | Hu, Qiongxia | Chen, Lanming
Vibrio parahaemolyticus is a causative agent of human serious seafood-borne gastroenteritis disease and even death. Shrimps, often eaten raw or undercooked, are an important reservoir of the bacterium. In this study, we isolated and characterized a total of 400 V. parahaemolyticus strains from commonly consumed fresh shrimps (Litopenaeus vannamei, Macrobrachium rosenbergii, Penaeus monodon, and Exopalaemon carinicauda) in Shanghai fish markets, China in 2013–2014. The results revealed an extremely low occurrence of pathogenic V. parahaemolyticus carrying two major toxic genes (tdh and trh, 0.0 and 0.5 %). However, high incidences of antibiotic resistance were observed among the strains against ampicillin (99 %), streptomycin (45.25 %), rifampicin (38.25 %), and spectinomycin (25.50 %). Approximately 24 % of the strains derived from the P. monodon sample displayed multidrug resistant (MDR) phenotypes, followed by 19, 12, and 6 % from the E. carinicauda, L. vannamei, and M. rosenbergii samples, respectively. Moreover, tolerance to heavy metals of Cr³⁺ and Zn²⁺ was observed in 90 antibiotic resistant strains, the majority of which also displayed resistance to Cu²⁺ (93.3 %), Pb²⁺ (87.8 %), and Cd²⁺(73.3 %). The pulsed-field gel electrophoresis (PFGE)-based genotyping of these strains revealed a total of 71 distinct pulsotypes, demonstrating a large degree of genomic variation among the isolates. The wide distribution of MDR and heavy-metal resistance isolates in the PFGE clusters suggested the co-existence of a number of resistant determinants in V. parahaemolyticus population in the detected samples. This study provided data in support of aquatic animal health management and food safety risk assessment in aquaculture industry.
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