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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.
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.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]Chronic toxicity of an environmental contaminant mixture to young (or larval) striped bass.
1987
Mehrle P.M. | Cleveland L. | Buckler D.R.
Treatment of biodigested coffee processing wastewater using Fenton’s oxidation and coagulation/flocculation 全文
2020
Gomes de Barros, Valciney | Rodrigues, Carmen S.D. | Botello-Suárez, Wilmar Alirio | Duda, Rose Maria | Alves de Oliveira, Roberto | da Silva, Eliana S. | Faria, Joaquim L. | Boaventura, Rui A.R. | Madeira, Luis M.
Biodigested coffee processing wastewater (CPW) presents a high organic load and does not meet the limits imposed by legislation (namely in Brazil) for discharge into water bodies. Anaerobic digestion generally cannot provide a satisfactory organic matter reduction in CPW as a significant fraction of recalcitrant compounds still persists in the treated effluent. So, this study aims to find alternative ways to remove refractory organic compounds from this wastewater in order to improve the biodegradability and reduce the toxicity, which will allow its recirculation back into the anaerobic digester. Three treatment approaches (Fenton’s oxidation - Approach 1, Coagulation/flocculation (C/F) - Approach 2, and the combination of C/F with Fenton’s process - Approach 3) were selected to be applied to the biodigested CPW in order to achieve that objective.The application of the Fenton process under the optimal operating conditions (initial pH = 5.0; T = 55 °C, [Fe³⁺] = 1.8 g L⁻¹ and [H₂O₂] = 9.0 g L⁻¹) increased the biodegradability (the BOD₅:COD ratio raised from 0.34 ± 0.02 in biodigested CPW to 0.44 ± 0.01 after treatment) and eliminated the toxicity (0.0% of Vibrio fischeri inhibition) along with moderate removals of organic matter (51.3%, 55.7% and 39.7% for total organic carbon – TOC, chemical oxygen demand – COD and biochemical oxygen demand - BOD₅, respectively). The implementation of a coagulation/flocculation process upstream from Fenton’s oxidation, under the best operating conditions (pH 10–11 and [Fe³⁺] = 250 mg L⁻¹), also allowed to slightly increase the biodegradability (from 0.34 to 0.47) and reduce the toxicity, whereas providing a higher removal of organic matter (TOC = 76.2%, COD = 76.5 and BOD₅ = 66.3% for both processes together). Approach 1 and Approach 3 showed to be the best ones, implying similar operating costs (∼74 R$ m⁻³/∼17 € m⁻³) and constitute an attractive option for managing biodigested CPW.
显示更多 [+] 显示较少 [-]NOx promotion of SO2 conversion to sulfate: An important mechanism for the occurrence of heavy haze during winter in Beijing 全文
2018
Ma, Jinzhu | Chu, Biwu | Liu, Jun | Liu, Yongchun | Zhang, Hongxing | He, Hong
In this study, concentrations of NOₓ, SO₂, O₃ and fine particles (PM₂.₅) were measured at three monitoring stations in Beijing during 2015. For extreme haze episodes during 25 Nov. - 3 Dec. 2015, observation data confirmed that high concentrations of NOₓ promoted the conversion of SO₂ to sulfate. Annual data confirmed that this is an important mechanism for the occurrence of heavy haze during winter in Beijing. Furthermore, in situ perturbation experiments in a potential aerosol mass (PAM) reactor were carried out at Shengtaizhongxin (STZX) station during both clean and polluted days. The concentrations of SO₄²⁻, NH₄⁺, NO₃⁻ and organic aerosol were positively related to the concentration of added NO₂. These results provide definitive evidence that NO₂ can promote the conversion of SO₂ to sulfate. At the same time, we found that NO₂ can promote the formation of NH₄⁺ and organic compounds in the aerosols. Our results illustrate that strengthened controls of nitrogen oxides is a key step in reducing the fine particles level in China.
显示更多 [+] 显示较少 [-]Assessment of status of three water bodies in Serbia based on tissue metal and metalloid concentration (ICP-OES) and genotoxicity (comet assay) 全文
2016
Sunjog, Karolina | Kolarević, Stoimir | Kračun-Kolarević, Margareta | Višnjić-Jeftić, Željka | Skorić, Stefan | Gačić, Zoran | Lenhardt, Mirjana | Vasić, Nebojša | Vuković-Gačić, Branka
Metals and metalloids are natural components of the biosphere, which are not produced per se by human beings, but whose form and distribution can be affected by human activities. Like all substances, they are a contaminant if present in excess compared to background levels and/or in a form that would not normally occur in the environment. Samples of liver, gills, gonads and muscle from European chub, Squalius cephalus, were analyzed for Al, As, B, Ba, Cr, Cu, Fe, Hg, Mn, Mo, Sr and Zn using inductively coupled plasma optical emission spectrometry (ICP-OES) to highlight the importance of tissue selection in monitoring research. The comet assay or single cell gel electrophoresis (SCGE) was selected as an in vivo genotoxicity assay, a rapid and sensitive method for measuring genotoxic effects in blood, liver and gills of the European chub. Microscopic images of comets were scored using Comet IV Computer Software (Perceptive Instruments, UK).The objective of our study was to investigate two reservoirs, Zlatar and Garasi, and one river, Pestan by: (i) determining and comparing metal and metalloid concentrations in sediment, water and tissues of European chub: liver, gills, muscle and gonads (ii) comparing these findings with genotoxicity of water expressed through DNA damage of fish tissues.A clear link between the level of metals in water, sediment and tissues and between metal and genotoxicity levels at examined sites was not found. This suggests that other xenobiotics (possibly the organic compounds), contribute to DNA damage.
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