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Volatile organic compounds in urban rivers and their estuaries in Osaka, Japan.
1997
Yamamoto K. | Fukushima M. | Kakutani N. | Kuroda K.
Polycyclic aromatic hydrocarbons in Norwegian forest soils: impact of long range atmospheric transport.
1996
Aamot E. | Steinnes E. | Schmid R.
Persistence and fate of polychlorinated biphenyls (PCBs) in sewage sludge-amended agricultural soils.
1996
Alcock R.E. | Bacon J. | Bardget R.D. | Beck A.J. | Haygarth P.M. | Lee R.G.M. | Parker C.A. | Jones K.C.
Kinetic constraints on the in-situ remediation of soils contaminated with organic chemicals.
1995
Beck A.J. | Jones K.C.
Observations on long-term air-soil exchange of organic contaminants.
1994
Jones K.C.
Evidence for long-term changes in the soil composition of selected organic compounds, brought about by exchanges with the atmosphere, is briefly reviewed. In the case of some compounds - such as benzo(a)pyrene and octachlorodibenzo-p-dioxin, soils may be significant long-term environmental sinks for atmospherically-derived material. In other cases - such as phenanthrene and some of the lighter PCBs, de-gassing or volatilisation from soil back to the air can occur under certain conditions. Hence the soil may act as a "short-term" sink, and a potential source to atmosphere. Indeed, for some 'semi-volatile' compounds used in large quantities in the past - such as PCBs, soil outgassing may actually be an extremely important source to contemporary air. Furthermore, soil outgassing from areas of former high use may provide an important driving mechanism for continued "global cycling" of a range of semi-volatile organochlorine compounds.
Mostrar más [+] Menos [-]Chronic toxicity of an environmental contaminant mixture to young (or larval) striped bass.
1987
Mehrle P.M. | Cleveland L. | Buckler D.R.
Microbiological remediation of waste-oil polluted soils -Ecotoxicological and toxicological considerations.
1994
Rippen G. | Held T. | Ripper P.
A waste-oil contaminated site situated near a river is supposed to be cleaned-up by means of different but complementary methods. On the basis of a research project, target values have been developed in close cooperation between the participant parties for the saturated and the unsaturated soil layers. The clean-up targets are introduced and discussed.
Mostrar más [+] Menos [-]The importance of total organic carbon and trihalomethane formation potential in monitoring of groundwater and surface water quality
1999
Ivancev-Tumbas, I. | Dalmacija, B. (Prirodno-matematicki fakultet, Novi Sad (Yugoslavia). Institut za hemiju)
Determination of total organic carbon content (TOC) and trihalomethane formation potential (THMFP) as well as correlation of those two parameters is recommended for monitoring of water bodies which are considered as drinking water resources. Those parameters would enable a categorization of water bodies from the protection point of view as well as from view of their usage as drinking water sources. Relationship between TOC and THMFP is dependent on the origin and the structure of organic matter in water. In this paper the correlation of TOC and THMFP is given for different kind of resources.
Mostrar más [+] Menos [-]Determination of non-extractable residues in soils: Towards a standardised approach Texto completo
2020
Loeffler, Dirk | Hatz, Annika | Albrecht, Dinah | Fligg, Marvin | Hogeback, Jens | Ternes, Thomas A.
After exposure of soils to anthropogenic organic chemicals non-extractable residues (NER) can be formed. The quantitative proportion of a compound which remains non-extractable is operationally defined by the extraction procedure employed and can be quantified only when using isotope labelled compounds (e.g. ¹⁴C or ¹³C). In Germany and the EU, there is no standardised procedure, how to determine NER, especially when different legal regulations apply. Consequently, the comparability of NER data is low. Hence, a major task of this study was the development of a general approach for the quantification of non-extractable residues (NER) in soils using radiotracer analysis.For that, extraction efficiencies were determined for 42 non-labelled organic chemicals spiked onto 3 soils applying a number of extraction techniques and conditions, developing an extraction procedure which provides high extraction efficiencies and a low variability for a broad spectrum of analytes.Additionally, NER generated within soil transformation studies according to OECD 307 using ¹⁴C-triclosan, ¹⁴C-fenoxycarb and ¹⁴C-acetaminophen were analysed using sequential batch extraction and pressurised liquid extraction (PLE). Depending on the extraction procedure used, the NER fraction related to ¹⁴C-triclosan in a soil varied greatly between 96% and 28%.In this study a widely universal extraction procedure was developed to improve the comparability of the NER data and limit overestimation of NER, which can be of enormous consequence for the assessment of persistence and environmental risk of organic chemicals. Furthermore, silylation, EDTA-extraction and HCl-treatment were compared regarding a further analysis of NER using radiotracer analysis.
Mostrar más [+] Menos [-]High molecular weight organic compounds (HMW-OCs) in severe winter haze: Direct observation and insights on the formation mechanism Texto completo
2016
Duan, F.K. | He, K.B. | Ma, Y.L. | Ihozaki, T. | Kawasaki, H. | Arakawa, R. | Kitayama, S. | Tujimoto, K. | Huang, T. | Kimoto, T. | Furutani, H. | Toyoda, M.
High molecular weight organic compounds (HMW-OCs), formed as secondary organic aerosols (SOA), have been reported in many laboratory studies. However, little evidence of HMW-OCs formation, in particular during winter season in the real atmosphere, has been reported. In January 2013, Beijing faced historically severe haze pollution, in which the hourly PM2.5 concentration reached as high as 974 μg m−3. Four typical haze events (HE1 to HE4) were identified, and HE2 (Jan. 9–16) was the most serious of these. Based on the hourly observed chemical composition of PM2.5 and the daily organic composition analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), we found that abundant ion peaks in m/z 200–850 appeared on heavy haze days, whereas these were negligible on a clear day, indicating the existence of HMW-OCs in the wintertime haze. A negative nonlinear correlation between HMW-OCs and O3 suggested that gas oxidation was not likely to be the dominant mechanism for HMW-OCs formation. During the heavy haze events, the relative humidity and mass ratio of H2O/PM2.5 reached as high as 80% and 0.2, respectively. The high water content and its good positive correlation with HMW-OCs indicated that an aqueous-phase process may be a significant pathway in wintertime. The evidence that acidity was much higher during HE2 (0.37 μg m−3) than on other days, as well as its strong correlation with HMW-OCs, indicated that acid-catalyzed reactions likely resulted in HMW-OCs formation during the heavy winter haze in Beijing.
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