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Responses and successions of sulfonamides, tetracyclines and fluoroquinolones resistance genes and bacterial community during the short-term storage of biogas residue and organic manure under the incubator and natural conditions
2018
Pu, Chengjun | Liu, Liquan | Yao, Meng | Liu, Hang | Sun, Ying
Biogas residue and organic manure are frequently used for crop planting. However, the evaluation of antibiotic resistant bacteria (ARB), antibiotic resistance genes (ARGs) and bacterial community before their applications to fields is still lacking. This study monitored the variations of bacteria resistant to sulfadiazine, tetracycline and norfloxacin, 57 resistance genes for sulfonamides, tetracyclines and fluoroquinolones as well as the bacterial community during the 28-day aerobic storage of biogas residue and organic manure by using viable plate counts, high-throughput qPCR and Illumina MiSeq sequencing methods. Then two storage conditions, incubator (25 °C) and natural environment, were used to assess the responses of ARB and ARGs to the environmental factors. Results showed that a total of 35 and 21 ARGs were detected in biogas residue and organic manure, respectively. ARB and ARGs were enriched up to 8.01-fold in biogas residue after the 28-day storage, but varied in a narrow range during the storage of organic manure. Compared with the incubator condition, the proliferation of ARB and ARGs in biogas residue under the natural condition was relatively inhibited by the varied and complicated environmental factors. However, we found that there was no significant difference of ARB and ARGs in organic manure between the incubator and natural conditions. Bacterial community was also shifted during the storage of biogas residue, especially Bacteroidetes_VC2.1_Bac22, Aequorivita, Luteimonas and Arenimonas. Network analysis revealed that the relationship in biogas residue was much more complicated than that in organic manure, which ultimately resulted in large successions of ARB and ARGs during the short-term storage of biogas residue. Therefore, we suggest that further measures should be taken before the application of biogas residue to fields.
اظهر المزيد [+] اقل [-]Radiological comparison of a FDNPP waste storage site during and after construction
2018
Connor, D.T. | Martin, P.G. | Pullin, H. | Hallam, K.R. | Payton, O.D. | Yamashiki, Y. | Smith, N.T. | Scott, T.B.
The clean-up effort that is occurring across the region affected by the 2011 Fukushima Daiichi Nuclear Power Plant accident is unprecedented in its magnitude as well as the financial cost that will eventually result. A major component of this remediation is the stripping of large volumes of material from the land surface, depositing this into large waste storage bags before placing these 1 cubic meter bags into specially constructed stores across Fukushima Prefecture.In this work, using an unmanned aerial vehicle to perform radiological surveys of a site, the time-resolved distribution of contamination during the construction of one of these waste storage sites was assessed. The results indicated that radioactive material was progressively leaching from the store into the surrounding environment. A subsequent survey of the site conducted eight months later revealed that in response to this survey and remedial actions, the contamination issue once existing on this site had been successfully resolved. Such results highlight the potential of low-altitude unmanned aerial systems to easily and rapidly assess site-wide changes over time – providing highly-visual results; therefore, permitting for prompt remedial actions to be undertaken as required.Use of UAV radiation mapping and airborne photogrammetry to produce a time-resolved assessment of remediation efforts within a Fukushima temporary storage facility.
اظهر المزيد [+] اقل [-]Application of airborne photogrammetry for the visualisation and assessment of contamination migration arising from a Fukushima waste storage facility
2018
Connor, D.T. | Martin, P.G. | Smith, N.T. | Payne, L. | Hutson, C. | Payton, O.D. | Yamashiki, Y. | Scott, T.B.
Airborne systems such as lightweight and highly portable unmanned aerial vehicles (UAVs) are becoming increasingly widespread in both academia and industry - with an ever-increasing range of applications, including (but not limited to), air quality sampling, wildlife monitoring and land-use mapping.In this work, high-resolution airborne photogrammetry obtained using a multi-rotor system operating at low survey altitudes, is combined with ground-based radiation mapping data acquired at an interim storage facility for wastes removed as part of the large-scale Fukushima clean-up program. The investigation aimed to assess the extent to which the remediation program at a specific site has contained the stored contaminants, as well as present a new methodology for rapidly surveying radiological sites globally. From the three-dimensional rendering of the site of interest, it was possible to not only generate a powerful graphic confirming the elevated radiological intensity existing at the location of the waste bags, but also to also illustrate the downslope movement of contamination due to species leakage from the large 1m³ storage bags. The entire survey took less than 1 h to perform, and was subsequently post-processed using graphical information software to obtain the renderings. The conclusions within this study not only highlight the usefulness of incorporating three-dimensional renderings within radiation mapping protocols, but also conclude that current methods of monitoring these storage facilities in the long term could be improved through the integration of UAVs within the standard protocol.
اظهر المزيد [+] اقل [-]Effects of storage temperature and duration on release of antimony and bisphenol A from polyethylene terephthalate drinking water bottles of China
2014
Fan, Ying-Ying | Zheng, Jian-Lun | Ren, Jing-Hua | Luo, Jun | Cui, Xin-Yi | Ma, Lena Q.
We investigated effects of storage temperature and duration on release of antimony (Sb) and bisphenol A (BPA) from 16 brands of polyethylene terephthalate (PET) drinking water bottles in China. After 1-week storage, Sb release increased from 1.88–8.32 ng/L at 4 °C, to 2.10–18.4 ng/L at 25 °C and to 20.3–2604 ng/L at 70 °C. The corresponding releases for BPA were less at 0.26–18.7, 0.62–22.6, and 2.89–38.9 ng/L. Both Sb and BPA release increased with storage duration up to 4-week, but their releasing rates decreased with storage time, indicating that Sb and BPA release from PET bottles may become stable under long term storage. Human health risk was evaluated based on the worst case, i.e., storage at 70 °C for 4-week. Chronic daily intake (CDI) caused by BPA release was below USEPA regulation, Sb release in one brand exceeded USEPA regulated CDI (400 ng/kg bw/d) with values of 409 and 1430 ng/kg bw/d for adult and children.
اظهر المزيد [+] اقل [-]The life of a plastic butter tub in riverine environments
2021
Delorme, Astrid E. | Koumba, Gaelle B. | Roussel, Erwan | Delor-Jestin, Florence | Peiry, Jean-Luc | Voldoire, Olivier | Garreau, Alexandre | Askanian, Haroutioun | Verney, Vincent
Plastic pollution in the world's ocean is one of the major environmental challenges that affects the society today, due to their persistence at sea, adverse consequences to marine life and being potentially harmful to human health. Rivers are now widely recognized as being the major input source of land-based plastic waste into the seas. Despite their key role in plastic transportation, riverine plastic pollution research is still in its infancy and plastic sources, hot-spots and degradation processes in riverine systems are to date poorly understood. In this contribution, we introduce a novel concept of following the aging of polypropylene based post-consumer goods placed in known trapping and mobility zones of macroplastics on a fluvial point bar, which was determined through repeated field surveys of macroplastic densities on this bar. As a proof-of-concept, we followed the degradation of 5 identical plastic butter tubs in 5 different locations on a riverbank and significant differences in the aging of the tubs were observed. The degree of aging of the tubs can to some extent be correlated to their proximity to the main river channel, exposure to natural conditions, such as solar radiation, and its storage time on land.
اظهر المزيد [+] اقل [-]Macroplastic transfer dynamics in the Loire estuary: Similarities and specificities with macrotidal estuaries
2022
Ledieu, L. | Tramoy, R. | Mabilais, D. | Ricordel, S. | Verdier, L. | Tassin, B. | Gasperi, J.
The quantification of macroplastic fluxes transferred by rivers toward the pelagic environment requires a better understanding of macrodebris transfer processes in estuarine environments. Following the strategy adopted in the Seine estuary, this study aims to characterize macroplastic trajectories in the Loire estuary. Between January 2020 and July 2021, 35 trajectories were monitored using plastic bottles equipped with GPS-trackers. With total travelled distances between 100 m and 103.6 km, trajectories show great spatiotemporal variability. The various forcing factors (macroplastic buoyancy, estuaries tidal and hydrometeorological conditions, geomorphology and vegetation) lead to chaotic trajectories, preventing accurate predictions in macroplastic transfer and storage/remobilization dynamics. In the Loire estuary like in the Seine one, no tracked bottle reached the Atlantic Ocean. It confirms that macrotidal estuaries under temperate climates constitute accumulation zones and slow pathways for macroplastics, but raises question on the real fluxes transferred from continental areas to oceans.
اظهر المزيد [+] اقل [-]Toxic substance storage tank containment
1985
[How to reduce agricultural nitrogen losses?]
1993
Pedersen, C.Aa.
Effects of storage conditions of biological materials on the contents of organochlorine compounds and mercury
1997
Boer, J. de | Smedes, F. (DLO-Netherlands Institute for Fisheries Research, P.O. Box 68, 1970 AB IJmuiden (Netherlands))
The Treatment Performance and the Bacteria Preservation of Anammox: A Review
2015
He, Shilong | Niu, Qigui | Ma, Haiyuan | Zhang, Yanlong | Li, Yu-You
Because of the low energy costs in the absence of the need for aeration, the non-requirement of a carbon source and alkali, and the reduced production of excess sludge, anaerobic ammonia oxidation (Anammox) has been extensively studied as an alternative to the conventional nitrification–denitrification pathway for biological nitrogen removal from wastewater. However, many challenges remain which need to be overcome to prepare the process for engineering application. These include the long doubling time of Anammox bacteria/autotrophic ammonia-oxidizing bacteria (AAOB), the low tolerance capacity to substrate concentration, and high sensitivity to various environmental factors. This review article focuses on the main drawbacks of the Anammox process and evaluates the progress made to date with regard to the enrichment of AAOB and the treatment performance of the Anammox process itself. The factors affecting the nitrogen removal performance of the Anammox process, such as substrate concentration, organic matters, and variation of temperature, are also reviewed and discussed. Finally, the need for the development of long-term storage methods for AAOB is addressed.
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