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  • 1.
    Allegrini, Elisa
    et al.
    Technical University of Denmark, Department of Environmental Engineering.
    Boldrin, Alessio
    Tech Univ Technical University of Denmark, Department of Environmental Engineering.
    Jansson, Stina
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Lundtorp, Kasper
    Babcock & Wilcox Vølund A/S, Göteborg, Sweden.
    Fruergaard Astrup, Thomas
    Technical University of Denmark, Department of Environmental Engineering.
    Quality and generation rate of solid residues in the boiler of a waste-to-energy plant2014In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 270, p. 127-136Article in journal (Refereed)
    Abstract [en]

    The Danish waste management system relies significantly on waste-to-energy (WtE) plants. The ash produced at the energy recovery section (boiler ash) is classified as hazardous waste, and is commonly mixed with fly ash and air pollution control residues before disposal. In this study, a detailed characterization of boiler ash from a Danish grate-based mass burn type WtE was performed, to evaluate the potential for improving ash management. Samples were collected at 10 different points along the boiler's convective part, and analysed for grain size distribution, content of inorganic elements, polychlorinated dibenzo-. p-dioxins and dibenzofurans (PCDD and PCDF), and leaching of metals. For all samples, PCDD and PCDF levels were below regulatory limits, while high pH values and leaching of e.g. Cl were critical. No significant differences were found between boiler ash from individual sections of the boiler, in terms of total content and leaching, indicating that separate management of individual ash fractions may not provide significant benefits. 

  • 2.
    Augulyte, Lijana
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Kliaugaite, Daina
    Racys, Viktoras
    Jankunaite, Dalia
    Zaliauskiene, Audrone
    Bergqvist, Per-Anders
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Andersson, Patrik L
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Multivariate analysis of a biologically activated carbon (BAC) system and its efficiency for removing PAHs and aliphatic hydrocarbons from wastewater polluted with petroleum products2009In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 170, no 1, p. 103-110Article in journal (Refereed)
    Abstract [en]

    The efficiency of a biologically activated carbon system for treating wastewater polluted with petroleum products was examined and the effects of process parameters on its efficacy were evaluated. In each experiment 17 alkylated and 19 non-alkylated polycyclic aromatic hydrocarbons (PAHs) and total petroleum hydrocarbons (TPHs, C10-C40) were extracted using semipermeable membrane devices from wastewater before and after treatment. The acquired data during experiments were analyzed using principal component analysis (PCA). The treatment system robustly removed dissolved PAHs across the studied ranges of the process parameters, providing overall removal efficiencies of 96.9-99.7% for the sum of 36 PAHs. However, the major contributor to their removal was sorption rather than biodegradation, and despite the general efficiency of the process there was up to a 9-fold range in the sums of quantified PAHs in the effluents between experiments. Combinations of long process contact time (24 h) with high temperature (24 degrees C) and moderate oxygen concentration (6-7mg O2 L-1) resulted in good removal of bioavailable PAHs. The removal of TPHs was more dependent on biological activities during the wastewater treatment, and consequently more dependent on the process parameters. In addition, small but significant proportions of PAHs were volatilized and released during the wastewater treatment.

  • 3.
    Badea, Silviu
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Lundstedt, Staffan
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Liljelind, Per
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Tysklind, Mats
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    The influence of soil composition on the leachability of selected hydrophobic organic compounds (HOCs) from soils using a batch leaching test2013In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 254, p. 26-35Article in journal (Refereed)
    Abstract [en]

    The influence of soil composition (peat and clay content) on the leachability was investigated in batch leaching experiments for chemically diverse hydrophobic organic compounds (HOCs: PCP, PAHs, HCB, HCHs, PCBs, and TCDD/Fs). An experimental design was applied to generate 8 diverse soil matrices, and the results were evaluated by orthogonal projections to latent structures (OPLS), as well as compound specific response surface models. Overall, the distribution coefficients (log Kd) of model HOCs were in the range of approx. 2.0–5.7. The Kd-values of HCHs, phenanthrene and PCP were positively correlated with the peat content. Kd-values of benzo(a)anthracene, HCB, and PCB 47 were positively correlated with both peat and clay content. The Kd-values of 1,3,6,8-TCDD and 1,3,6,8-TCDF were positively correlated with peat content but negatively correlated with clay content, while for PCB 153 and PCB 155 the correlations were reversed. The correlation between the Kd-values and the compounds’ Kow-values was linearly for compounds with log Kow <6. For HOCs with log Kow > 6, the Kd-values were leveling off, possibly due to small particles in the leachates. Our study demonstrated how complex interaction between both the organic matter and clay components influences the leachability of HOCs in a compound-specific manner.

  • 4.
    Blum, Kristin M.
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Umeå University.
    Gallampois, Christine
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Andersson, Patrik L.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Renman, G.
    Renman, A.
    Haglund, Peter
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Comprehensive assessment of organic contaminant removal from on-site sewage treatment facility effluent by char-fortified filter beds2019In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 361, p. 111-122Article in journal (Other academic)
    Abstract [en]

    The removal of organic contaminants from wastewater using cost-efficient and easily accessible methods have been increasingly studied in recent years. Most studies have focused on municipal sewage treatment plants; however, our study investigated treatment with char-fortified filter beds for on-site sewage treatment facilities (OSSFs). OSSFs are commonly used in rural and semi-urban areas all over the world to treat wastewater to reduce eutrophication and water-related diseases. To screen for a wide range of organic contaminants in order to improve the understanding of wastewater treatment efficiency and molecular properties, samples were taken from an OSSF field study site that used three filter types: sand, char-fortified sand, and char-fortified gas concrete. First, we screened for organic contaminants with state-of-the-art gas chromatography and liquid chromatography mass spectrometry-based targeted and untargeted analysis and then we developed quantitative structure-property relationship models to find the key molecular features responsible for the removal of organic contaminants. We identified 74 compounds, of which 24 were confirmed with reference standards. Amongst these 74 compounds were plasticizers, UV stabilizers, fragrances, pesticides, surfactant and polymer impurities, pharmaceuticals and their metabolites, and many biogenic compounds. Sand filters that are sometimes used as a last treatment step in OSSFs can remove hydrophobic contaminants. The addition of biochar significantly increases the removal of these and a few hydrophilic compounds (Wilcoxon signed-rank test, α = 0.05). Gas concrete did not appear to be suitable for the removal of organic contaminants. This study showed that, besides hydrophobic effects, biodegradation is the most important removal pathway in long-term field applications. However, further improvements are necessary to remove very hydrophilic contaminants as they were not removed with sand and biochar-fortified sand.

  • 5. Cuklev, Filip
    et al.
    Fick, Jerker
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Cvijovic, Marija
    Kristiansson, Erik
    Förlin, Lars
    Larsson, D G Joakim
    Does ketoprofen or diclofenac pose the lowest risk to fish?2012In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 229-230, p. 100-106Article in journal (Refereed)
    Abstract [en]

    Ketoprofen and diclofenac are non-steroidal anti-inflammatory drugs (NSAIDs) often used for similar indications, and both are frequently found in surface waters. Diclofenac affects organ histology and gene expression in fish at around 1μg/L. Here, we exposed rainbow trout to ketoprofen (1, 10 and 100μg/L) to investigate if this alternative causes less risk for pharmacological responses in fish. The bioconcentration factor from water to fish blood plasma was <0.05 (4 for diclofenac based on previous studies). Ketoprofen only reached up to 0.6‰ of the human therapeutic plasma concentration, thus the probability of target-related effects was estimated to be fairly low. Accordingly, a comprehensive analysis of hepatic gene expression revealed no consistent responses. In some contrast, trout exposed to undiluted, treated sewage effluents bioconcentrated ketoprofen and other NSAIDs much more efficiently, according to a meta-analysis of recent studies. Neither of the setups is however an ideal representation of the field situation. If a controlled exposure system with a single chemical in pure water is a reasonable representation of the environment, then the use of ketoprofen is likely to pose a lower risk for wild fish than diclofenac, but if bioconcentration factors from effluent-exposed fish are applied, the risks may be more similar.

  • 6. Gros, Meritxell
    et al.
    Blum, Kristin
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Jernstedt, Henrik
    Renman, Gunno
    Rodríguez-Mozaz, Sara
    Haglund, Peter
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Andersson, Patrik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Wiberg, Karin
    Ahrens, Lutz
    Screening and prioritization of micropollutants in wastewaters from on-site sewage treatment facilities2017In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 328, p. 37-45Article in journal (Refereed)
    Abstract [en]

    A comprehensive screening of micropollutants was performed in wastewaters from on-site sewage treatment facilities (OSSFs) and urban wastewater treatment plants (WWTPs) in Sweden. A suspect screening approach, using high resolution mass spectrometry, was developed and used in combination with target analysis. With this strategy, a total number of 79 micropollutants were successfully identified, which belong to the groups of per- and polyfluoroalkyl substances (PFASs), pesticides, phosphorus-containing flame retardants (PFRs) and pharmaceuticals and personal care products (PPCPs). Results from this screening indicate that concentrations of micropollutants are similar in influents and effluents of OSSFs and WWTPs, respectively. Removal efficiencies of micropollutants were assessed in the OSSFs and compared with those observed in WWTPs. In general, removal of PFASs and PFRs was higher in package treatment OSSFs, which are based on biological treatments, while removal of PPCPs was more efficient in soil bed OSSFs. A novel comprehensive prioritization strategy was then developed to identify OSSF specific chemicals of environmental relevance. The strategy was based on the compound concentrations in the wastewater, removal efficiency, frequency of detection in OSSFs and on in silico based data for toxicity, persistency and bioaccumulation potential.

  • 7. Heinälä, Milla
    et al.
    Gundert-Remy, Ursula
    Heraty Wood, Maureen
    Ruijten, Marc
    M.J. Bos, Peter
    Zitting, Antti
    Bull, Sarah
    Russell, David
    Nielsen, Elsa
    Cassel, Gudrun
    Swedish Defence Research Agency (FOI).
    Leffler, Per
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine. Swedish Defence Research Agency (FOI).
    Tissot, Sylvie
    Vincent, Jean-Martin
    Santonen, Tiina
    Survey on methodologies in the risk assessment of chemical exposures in emergency response situations in Europe2013In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 244, p. 545-554Article in journal (Refereed)
    Abstract [en]

    A scientifically sound assessment of the risk to human health resulting from acute chemical releases is the cornerstone for chemical incident prevention, preparedness and response. Although the general methodology to identify acute toxicity of chemicals has not substantially changed in the last decades, there is ongoing debate on the current approaches for human health risk assessment in scenarios involving acute chemical releases.

    A survey was conducted to identify 1) the most important present and potential future chemical incident scenarios and anticipated changes in chemical incidents or their management; 2) information, tools and guidance used in different countries to assess health risks from acute chemical releases; and 3) needs for new information, tools, guidance and expertise to enable the valid and rapid health risk assessment of acute chemical exposures.

    According to the results, there is an obvious variability in risk assessment practices within Europe. The multiplicity of acute exposure reference values appears to result in variable practices. There is a need for training especially on the practical application of acute exposure reference values. Although acutely toxic and irritating/corrosive chemicals will remain serious risks also in future the development of plausible scenarios for potential emerging risks is also needed. This includes risks from new mixtures and chemicals (e.g. nanoparticles).

  • 8. Holmberg, Anna
    et al.
    Fogel, Jenny
    Albertsson, Eva
    Fick, Jerker
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Brown, Jeffrey N
    Paxéus, Nicklas
    Förlin, Lars
    Johnsson, Jörgen I
    Larsson, D G Joakim
    Does waterborne citalopram affect the aggressive and sexual behaviour of rainbow trout and guppy?2011In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 187, no 1-3, p. 596-599Article in journal (Refereed)
    Abstract [en]

    Citalopram is one of several selective serotonin reuptake inhibitors (SSRIs) commonly found in treated sewage effluents. Accordingly, there are concerns about possible adverse effects of SSRIs on aquatic organisms, particularly behavioural effects similar to those associated with SSRI use in humans. Rainbow trout fry and adult male guppies were therefore exposed to waterborne citalopram, ranging from environmentally relevant to high concentrations (1, 10, 100μg/L) for 3-7 days. Under these experimental conditions citalopram does not appear to cause significant effects on aggression in rainbow trout fry or on sexual behaviour in male guppies. This may be explained by a relatively low uptake of citalopram from water to fish.

  • 9.
    Jonsson, Sofia
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Lind, Henrik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Lundstedt, Staffan
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Haglund, Peter
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Tysklind, Mats
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Dioxin removal from contaminated soils by ethanol washing2010In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, ISSN 0304-3894, Vol. 179, no 1-3, p. 393-399Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to investigate the potential utility of ethanol washing for remediating soils contaminated with polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), as a cost-efficient alternative to conventional remediation methods of PCDD/F-contaminated soils. Initially, screening experiments were performed with a two-level full factorial design to examine the effects of temperature, extraction time and ethanol concentration on the removal efficiency. The screening experiments showed that the ethanol concentration was the most important parameter. In addition, repeated washing cycles considerably improved the results. Ethanol washing conditions were then selected (10 wash cycles with 75% ethanol at 60 °C), and applied to four soils with different soil characteristics and contamination levels to test the robustness of the selected method. Treatment efficiencies of 81% and 85% were obtained for a lightly contaminated sandy–silty soil and a highly contaminated clay soil rich in graphite particles, respectively. Even higher treatment efficiencies (≥97%) were obtained for two other highly contaminated soils, one of which contained high amounts of organic matter. PCDD/Fs were found to both dissolve in the solvent and migrate into it as species adsorbed to particles. The relative contributions of these mechanisms and the overall efficiency of the removal seem to depend on contaminant concentration, the types of carbon in the soil matrix and the particle size distribution. The study shows that ethanol washing has effective remediation potential for a variety of PCDD/F-contaminated soils.

     

  • 10.
    Kozyatnyk, Ivan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Bouchet, Sylvain
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Björn, Erik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Haglund, Peter
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Fractionation and size-distribution of metal and metalloid contaminants in a polluted groundwater rich in dissolved organic matter2016In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 318, p. 194-202Article in journal (Refereed)
    Abstract [en]

    We investigated the concentration levels, fractionation and molecular weight distribution (MWD) of dissolved organic matter (DOM) and metals (V, Cr, Co, Ni, Cu, Zn, As, Cd, Sn, Ba, Hg and Pb) in a polluted groundwater from an industrial area in Northern Sweden. DOM was mainly recovered in the hydrophobic acidic and hydrophobic neutral sub-fractions (45 and 35%, respectively) while most metals were found in the acidic sub-fractions (46–93%) except for V, Fe and As, which were predominant in the basic sub-fractions (74–93%) and Cd in the neutral ones (50%). DOM exhibited a broad MWD in groundwaters, usually from 5 to 200 kDa and was dominated by high molecular weight hydrophobic acids, low molecular weight hydrophilic acids and hydrophilic neutral compounds. Most of the studied metals (Fe, Cr, Co, Sn, Ba, Hg) were associated with the high molecular weight DOM fraction (ca. 40–100 kDa). Cu, Pb, Zn, Cd and Ni interacted with a broad range of DOM size fractions but were still most abundant in the high molecular weight fraction. Few metal/metalloids (As, V and Cr in some cases) presented a very weak affinity for DOM and presumably existed predominantly as “free” inorganic ions in solution.

  • 11. Qian, Yan
    et al.
    Wang, Xiao-li
    Lv, Zhan-lu
    Tysklind, Mats
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Guo, Chen
    Liang, Bao
    Wu, Jia-bing
    Yang, Yong-jian
    Yang, Yi-shu
    Wang, Fei-fei
    Duan, Xiao-li
    Ma, Jin
    Wei, Yong-jie
    Wang, Chun-hui
    Yang, Li-xin
    Zhang, Jin-liang
    Shi, Xiao-ming
    Wang, Xian-liang
    Quantification for total demethylation potential of environmental samples utilizing the EGFP reporter gene2016In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 306, p. 278-285Article in journal (Refereed)
    Abstract [en]

    Abstract The demethylation potential of pollutants is arguably an innate component of their toxicity in environmental samples. A method was developed for determining the total demethylation potential of food samples (TDQ). The demethylation epigenetic toxicity was determined using the Hep G2 cell line transfected with pEGFP-C3 plasmids containing a methylated promoter of the EGFP reporter gene. The total demethylation potential of the sample extracts (the 5-AZA-CdR demethylation toxic equivalency) can be quantified within one week by using a standard curve of the 5-AZA-CdR demethylation agent. To explore the applicability of TDQ for environmental samples, 17 groundwater samples were collected from heavy polluted Kuihe river and the total demethylation potentials of the sample extracts were measured successfully. Meaningful demethylation toxic equivalencies ranging from 0.00050 to 0.01747 μM were found in all groundwater sample extracts. Among 19 kinds of inorganic substance, As and Cd played important roles for individual contribution to the total demethylation epigenetic toxicity. The TDQ assay is reliable and fast for quantifying the DNA demethylation potential of environmental sample extracts, which may improve epigenetic toxicity evaluations for human risk assessment, and the consistent consuming of groundwater alongside the Kuihe river pose unexpected epigenetic health risk to the local residents.

  • 12. Reinik, Janek
    et al.
    Heinmaa, Ivo
    Kirso, Uuve
    Kallaste, Toivo
    Ritamäki, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Pongrácz, Eva
    Huuhtanen, Mika
    Larsson, William
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Keiski, Riitta
    Kordás, Krisztián
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Mikkola, Jyri-Pekka
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Alkaline modified oil shale fly ash: Optimal synthesis conditions and preliminary tests on CO(2) adsorption2011In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 196, p. 180-186Article in journal (Refereed)
    Abstract [en]

    Environmentally friendly product, calcium-silica-aluminum hydrate, was synthesized from oil shale fly ash, which is rendered so far partly as an industrial waste. Reaction conditions were: temperature 130 and 160°C, NaOH concentrations 1, 3, 5 and 8M and synthesis time 24h. Optimal conditions were found to be 5M at 130°C at given parameter range. Original and activated ash samples were characterized by XRD, XRF, SEM, EFTEM, (29)Si MAS-NMR, BET and TGA. Semi-quantitative XRD and MAS-NMR showed that mainly tobermorites and katoite are formed during alkaline hydrothermal treatment. Physical adsorption of CO(2) on the surface of the original and activated ash samples was measured with thermo-gravimetric analysis. TGA showed that the physical adsorption of CO(2) on the oil shale fly ash sample increases from 0.06 to 3-4mass% after alkaline hydrothermal activation with NaOH. The activated product has a potential to be used in industrial processes for physical adsorption of CO(2) emissions.

  • 13. Viipsi, Karin
    et al.
    Sjöberg, Staffan
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Tõnsuaadu, Kaia
    Shchukarev, Andrey
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Hydroxy- and fluorapatite as sorbents in Cd(II) - Zn(II) multi-component solutions in the absence/presence of EDTA2013In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 252-253, p. 91-98Article in journal (Refereed)
    Abstract [en]

    Apatites are suitable sorbent materials for contaminated soil and water remediation because of their low solubility and ability to bind toxic metals into their structure. Whereas in soil/water systems different complexing ligands are present, it is important to examine how these ligands affect apatite metal sorption process. The removal of cadmium (Cd) and zinc (Zn) ions from aqueous solutions by hydroxyapatite (HAP) and fluorapatite (FAP) was investigated by batch experiments with and without EDTA being present in the pH range 4 to 11. The surface composition of the solid phases was analysed by X-ray photoelectron spectroscopy (XPS). The surface layer of apatites (AP), according to the (Ca + Cd + Zn):P atomic ratio, remained constant (1.4 ± 0.1) through an ion exchange. The amount of Cd2+ and Zn2+ removed increased with increasing pH. The removed amount of Zn2+ was higher than Cd2+. In the Cd-Zn binary system, competitive sorption reduced the individual removed amounts but the total maximum sorption was approximately constant. In the presence of EDTA, Cd2+ and Zn2+ removal was reduced because of the formation of [CdEDTA]2− and [ZnEDTA]2− in solution. XPS revealed an enrichment of AP surface by Cd2+ and Zn2+ and formation of new surface solid-solution phase with the general composition Ca8.4-xMex(HPO4)1.6(PO4)4.4(OH)0.4.

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