| 1. |
- Björklund, Karin, 1979
(författare)
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Adsorbents for the removal of contaminants from stormwater
- 2015
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Ingår i: BC Water & Waste Association Annual Conference & Trade Show, Book of Abstracts.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Contaminated urban runoff is a major cause of concern for water quality and aquatic ecosystems worldwide. Recent research shows that stormwater often contains metals and emerging organic contaminants at levels exceeding environmental quality standards. To comply with quality guidelines for receiving waters, stormwater treatment is considered to be critical. Filtration of stormwater through an adsorptive material is one of the most promising techniques for removal of particulate, colloidal and dissolved pollutants. The aim of this research was to use laboratory-based experiments to determine the removal capacity of selected sorbents for organic pollutants and metals found in stormwater. The ideal sorbent should be efficient in removing pollutants, inexpensive, abundant and easily accessible. A variety of materials, including minerals, wood- and bark-based media, were subjected to batch tests. By comparing the capacity of a range of sorbents under identical laboratory conditions, the most promising sorbent can be identified.The study revealed that cellulose and minerals adsorbed organic pollutants to a negligible degree. However, these materials may serve as efficient adsorbents of metals because of their potential to attract cations. Sawdust and bark efficiently and promptly sorbed organic compounds, whereas their capacity for metals was found to be low. Activated carbon produced from sewage sludge exhibited substantially higher adsorption capacity for organic pollutants than the wood- and bark-based media tested.
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| 2. |
- Björklund, Karin, 1979, et al.
(författare)
-
Adsorption of Organic Pollutants in Stormwater: Evaluation of Four Potential Sorbents
- 2014
-
Ingår i: Proceedings of the 13th International Conference on Urban Drainage.
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Konferensbidrag (refereegranskat)abstract
- Adsorption filters is one of the most promising techniques for removal of dissolved, colloidal and particulate pollutants from stormwater. The aim of this study was to compare the capacity of four filter materials – zeolite, cellulose, polypropylene/polyethylene (PP/PE) fibres and pine bark – to adsorb organic pollutants frequently detected in stormwater. In batch tests, synthetic stormwater spiked with polycyclic aromatic hydrocarbons (PAHs), alkylphenols and phthalates was contacted with media for up to 24 h. The compounds were then liquid-liquid extracted and analyzed using GC-MS. Zeolite and cellulose showed very low sorption capacity for the organic contaminants, whereas >70% of the initial concentration of all tested compounds was removed using PP/PE fibres, and >80% with pine bark. The highest adsorption capacity was found for PAHs (up to 44 µg/g) using PP/PE fibres and bark. For all tested compounds, maximum adsorption was approached within 30 min using these materials. Future research using natural stormwater should investigate the effect of colloidal transport of pollutants through PP/PE fibres and pine bark and the materials’ capacities to adsorb other pollutants, including metals.
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| 3. |
- Björklund, Karin, 1979, et al.
(författare)
-
Adsorption of Organic Stormwater Pollutants onto Activated Carbon from Sewage Sludge
- 2017
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Ingår i: Journal of Environmental Management. - : Elsevier BV. - 0301-4797 .- 1095-8630. ; 197, s. 490-497
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Tidskriftsartikel (refereegranskat)abstract
- Adsorption filters have the potential to retain suspended pollutants physically, as well as attracting andchemically attaching dissolved compounds onto the adsorbent. This study investigated the adsorption ofeight hydrophobic organic compounds (HOCs) frequently detected in stormwater e including fourpolycyclic aromatic hydrocarbons (PAHs), two phthalates and two alkylphenols e onto activated carbonproduced from domestic sewage sludge. Adsorption was studied using batch tests. Kinetic studiesindicated that bulk adsorption of HOCs occurred within 10 min. Sludge-based activated carbon (SBAC)was as efficient as tested commercial carbons for adsorbing HOCs; adsorption capacities ranged from 70to 2800 mg/g (Cinitial ¼ 10e300 mg/L; 15 mg SBAC in 150 mL solution; 24 h contact time) for each HOC. Inthe batch tests, the adsorption capacity was generally negatively correlated to the compounds' hydrophobicity(log Kow) and positively associated with decreasing molecule size, suggesting that molecularsieving limited adsorption. However, in repeated adsorption tests, where competition between HOCs wasmore likely to occur, adsorbed pollutant loads exhibited strong positive correlation with log Kow. Sewagesludge as a carbon source for activated carbon has great potential as a sustainable alternative for sludgewaste management practices and production of a high-capacity adsorption material.
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| 4. |
- Björklund, Karin, 1979, et al.
(författare)
-
Best Management Practices to Reduce Phthalate and Nonylphenol Loads in Urban Runoff
- 2008
-
Ingår i: Proceedings of the International Conference on Urban Drainage, 1-5 September, Edinburgh, UK.
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Konferensbidrag (refereegranskat)abstract
- Phthalates and nonylphenols, organic substances of widespread use, are believed to be ubiquitous in Swedish stormwater and urban sediments. Due to their reported hazardous properties, it is of great interest to identify effective best management practices (BMPs) to reduce the release of these substances to recipient waters. The stormwater-quality model SEWSYS was used to identify sources and quantify loads of phthalates and nonylphenols in two urban catchment areas. Based on the modelling results, BMPs were proposed, and their efficiencies evaluated. The SEWSYS simulations showed that discharges of phthalates and nonylphenols depend on catchment area characteristics: pollutants in a residential area originate mainly from building materials, whereas vehicles are the dominant source in a high-density traffic area. By replacing traditional building materials by phthalate and nonylphenol-free alternatives and by implementing congestion taxes to reduce traffic, the simulated pollutant loads could be reduced by more than 20% in the high-density traffic area. However, discharges from many diffuse sources cannot entirely be stopped, and a structural BMP, e.g. a sedimentation pond, is essential to further decrease pollutant loads in urban runoff. This study shows that SEWSYS can be a useful tool for selecting and evaluating adequate BMPs to reduce stormwater contamination.
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| 5. |
- Björklund, Karin, 1979, et al.
(författare)
-
Evaluation of low-cost materials for sorption of hydrophobic organic pollutants in stormwater
- 2015
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Ingår i: Journal of Environmental Management. - : Elsevier BV. - 0301-4797 .- 1095-8630. ; 159, s. 106-114
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Tidskriftsartikel (refereegranskat)abstract
- Conventional stormwater treatment techniques such as sedimentation and filtration are inefficient for removing the dissolved and colloidal phases of hydrophobic organic compounds (HOCs) present in stormwater. Adsorption could be a promising technique for removing colloidal and dissolved pollutants. Five low-cost sorbent materials were investigated in this project, including two minerals - vermiculite and perlite - and three waste products - two pine barks and a sawdust - as potential adsorbents for removal of polycyclic aromatic hydrocarbons (PAHs), alkylphenols and phthalates; HOCs commonly found in stormwater. Adsorption capacity and kinetics were studied through batch adsorption tests using synthetic stormwater spiked with a mixture of HOCs. Vermiculite and perlite exhibited insignificant removal of the organic contaminants. The three wood-based materials retained >80% of the initial HOC concentration (10-300μg/L). The two barks exhibited slightly higher adsorption capacities of HOCs than the sawdust. For all compounds tested, maximum adsorption onto the wood-based media was reached in
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| 6. |
- Björklund, Karin, 1979, et al.
(författare)
-
Evaluation of low-cost media for sorption of organic pollutants in stormwater
- 2014
-
Ingår i: World Environmental & Water Resources Congress 2014, Portland OR, USA, June 1-5, 2014.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Recent studies have shown that many organic compounds, including polycyclic aromatic hydrocarbons (PAHs) emitted through combustion and via petroleum sources, phthalate plasticizers and plastic additives such as alkylphenols, are found in stormwater at levels that exceed national and international water quality standards. This calls for efficient mitigation practices to reduce and eventually terminate the emission of these pollutants into stormwater and aquatic environments. Filtration of stormwater is one of the most promising technologies to remove particulate, colloidal and dissolved contaminants, provided that effective filtration and sorption materials are used. The aim of this research was to use laboratory-based experiments to determine the removal capacity of some selected sorbents for organic pollutants. A variety of materials previously used for metal and oil sorption, including minerals, wood- and bark-based media, were examined in 24 h batch tests using synthetic stormwater, spiked with humic acids (representing dissolved organic matter) and seven different organic pollutants. The samples were then centrifuged and filtered, liquid-liquid extracted, and analyzed using gas chromatography-mass spectrometry. As expected, the sorption tests showed that the minerals were ineffective for removing organic pollutants from stormwater. Despite its high water absorption capacity, cellulose sorbed organic contaminants only to a moderate degree. The bark-based media, however, were efficient sorbents. In general, the PAHs (90-95% of initial concentration removed) were more efficiently sorbed than alkylphenols (85-90%) and phthalates (75-85%) by bark. The results can be used as a guide in the selection of effective sorbents for the treatment of polluted stormwater in, for example, manhole filters, swales and rain gardens.
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| 7. |
- Björklund, Karin, 1979, et al.
(författare)
-
Hydrodynamic modelling of the influence of stormwater and combined sewer overflows on receiving water quality: Benzo(a)pyrene and copper risks to recreational water
- 2018
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Ingår i: Journal of Environmental Management. - : Elsevier BV. - 0301-4797 .- 1095-8630. ; 207, s. 32-42
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Tidskriftsartikel (refereegranskat)abstract
- The risk from chemical substances in surface waters is often increased during wet weather, due to surface runoff, combined sewer overflows (CSOs) and erosion of contaminated land. There are strong incentives to improve the quality of surface waters affected by human activities, not only from ecotoxicity and ecosystem health perspectives, but also for drinking water and recreational purposes. The aim of this study is to investigate the influence of urban stormwater discharges and CSOs on receiving water in the context of chemical health risks and recreational water quality. Transport of copper (Cu) and benzo[a]pyrene (BaP) in the Göta River (Sweden) was simulated using a hydrodynamic model. Within the 16 km modelled section, 35 CSO and 16 urban stormwater point discharges, as well as the effluent from a major wastewater treatment plant, were included. Pollutant concentrations in the river were simulated for two rain events and investigated at 13 suggested bathing sites. The simulations indicate that water quality guideline values for Cu are exceeded at several sites, and that stormwater discharges generally give rise to higher Cu and BaP concentrations than CSOs. Due to the location of point discharges and the river current inhibiting lateral mixing, the north shore of the river is better suited for bathing. Peak concentrations have a short duration; increased concentrations of the pollutants may however be present for several days after a rain event. Monitoring of river water quality indicates that simulated Cu and BaP concentrations are in the same order of magnitude as measured concentrations. It is concluded that hydrodynamic modelling is a useful tool for identifying suitable bathing sites in urban surface waters and areas of concern where mitigation measures should be implemented to improve water quality.
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| 8. |
- Björklund, Karin, 1979, et al.
(författare)
-
Källor till och flöden av ftalater och nonylfenoler i Stockholms dagvatten
- 2007
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- SEWSYS is a computer model designed for simulating fluxes of pollutants from its’ sources to the urban stormwater system. The model is able to simulate concentrations of substances in stormwater – thereby reducing the need for sampling and analyses of stormwater – as well as establishing the major sources of the pollutants in the urban environment. The aim of this work has been to identify the sources of some selected organic pollutants, adjusting SEWSYS to these new substances and simulating their fluxes in urban stormwater. The simulation results have then been used to investigate proper barriers to prevent these substances to reach the environment.The prioritised pollutants chosen to be studied were four phthalates – DBP, DEHP, DINP and DIDP – nonylphenols (NP) and their ethoxylates (NPE). Phthalates are plasticisers used in PVC (often as coil coating), paint and sealants. NP/E:s are surfactants used in a range of materials, such as concrete, paint and plastics. In order to add these pollutants into the SEWSYS model, the emission of each substance from each of the identified sources was scrutinised. Depending on the overall lack of data, assumptions and estimations were necessary to be made for the emission calculations.Two housing areas and one area dominated by traffic were selected for the modelling. Information on the prevalence of the different sources together with rainfall data were used for the simulation of stormwater runoff and pollution load. The model was calibrated with measured stormwater flows and volumes, as well as analysed concentrations of the pollutants in stormwater from the chosen housing and traffic areas. The traffic area showed high concentrations of phthalates in the stormwater samples. DIDP, and particularly DINP, showed the highest concentrations in most samples, both from the traffic area and the housing areas. The NP and NPE concentrations in most samples were close to or under the detection limits for the analytical methods used.The calibration of the model showed that the runoff module in SEWSYS is able to predict the runoff volume well. After recalculating and adjusting some of the emission factors, the concentrations of the pollutants were in the same magnitude as the measured values. The simulations showed that vehicles are the dominating source of the phthalates in the traffic area. Parking spaces and concrete are indicated to emit significant amounts of NP/E:s. In the housing areas the construction materials – such as plastic coated steel for roofing and cladding – were the most important sources of phthalates. Parking spaces tend to cause high pollution loads of NP/E:s.To reduce the load of organic pollutants in the environment a combination of barriers can be used – these barriers may include legislative measures to prohibit the use of a substance, recommendations to the consumers (not) to use specific construction materials or installing technical measures such as sedimentation facilities. A preliminary simulation show that by using construction materials free from phthalates or NP/E:s or reducing the traffic load, combined with a technical barrier such as a sedimentation pond, the pollution load from housing or traffic area is considerably decreased.
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| 9. |
- Björklund, Karin, 1979, et al.
(författare)
-
Metals and polycyclic aromatic hydrocarbons (PAHs) in stormwater sediments: particle distribution and catchment area emission factors (CAEFs)
- 2010
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Ingår i: Book of abstracts - 10th Urban Environment Symposium, 9-11 June 2010, Gothenburg, Sweden. ; , s. 19-
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Konferensbidrag (refereegranskat)abstract
- Emissions from traffic and construction materials contaminate stormwater with both metals and organicpollutants, and techniques for efficient removal of contaminants are reguested. The purpose of this studywas to determine the particle distribution of some selected metals and polycyclic aromatic hydrocarbons(PAHs) in a stormwater sedimentation facility, and to caiculate the emitted amounts of these contaminantsin the studied catchment area. Chemical analysis and determination of physical parameters wereperformed on sediments sampled at a stormwater treatment facility consisting of seven sedimentationchambers connected in series. The facility is located in central Gothenburg, Sweden, and receives runofffrom the E6 and E20 motorway, with a daily traffic bad of approximately 86 000 vehicies. Theconcentrations of the PAHs and metals showed a trend with sediment concentrations increasing from thefirst to the last chamber. The pollutant concentrations were weil correlated with the particle sizedistribution, dry densities, water and organic content of the sediments. in two or more of the chambers, theconcentrations of Cd, Pb, Cu, Zn, Ni, Cr and carcinogenic PAHs were higher than the given guideline vaiuesfor contaminated soil. The relative composition of the PAHs in sediment, with a dominance of pyrene,phenanthrene, fluoranthene and chrysene, indicates that rubber tyres, diesel exhaust and road asphaltcould be important sources of PAH pollution. The calculated catchment area emission factors (CAEFs)showed, in Wyear ha, the following order: petroleum hydrocarbons Cio - C4o (15 000) > Zn (3200) > Ni(~3000) > Cu (1500) > Sb (930) > Cr (820) > V (640)> Pb (260) > Co (120) > As (87) > Sn (25)> Mo (43)> ~16-EPA PAH (13) > Cresols (3.4) > Cd (1.3)> Hg (0.43). The results show that large parts of the finestsediment particle fractions, with high concentrations of the contaminants, are released with outiet waterfrom the sedimentation facility. The treatment facility could be more efficient if a filter was installed afterthe sedimentation steps, before discharge of water to the nearby stream.
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| 10. |
- Björklund, Karin, 1979, et al.
(författare)
-
Mineral Adsorbents for Removal of Metals in Urban Runoff
- 2014
-
Ingår i: European Geosciences Union General Assembly 2014.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this research was to determine the capacity of four different soil minerals to adsorb metals frequently detected in urban runoff. These are low-cost, natural and commercially available soil minerals. Contaminated surface runoff from urban areas is a major cause of concern for water quality and aquatic ecosystems worldwide. Pollution in urban areas is generated by a wide array of non-point sources, including vehicular transportation and building materials. Some of the most frequently detected pollutants in urban runoff are metals. Exhaust gases, tire wear and brake linings are major sources of such metals as Pb, Zn and Cu, while impregnated wood, plastics and galvanized surfaces may release As, Cd, Cr and Zn. Many metals have toxic effects on aquatic plants and animals, depending on metal speciation and bioavailability. The removal efficiency of pollutants in stormwater depends on treatment practices and on the properties the pollutant. The distribution of metals in urban runoff has shown, for example, that Pb is predominantly particle-associated, whereas Zn and Cd are present mainly in dissolved form. Many metals are also attached to colloids, which may act as carriers for contaminants, thereby facilitating their transport through conventional water treatment processes. Filtration of stormwater is one of the most promising techniques for removal of particulates, colloidal and truly dissolved pollutants, provided that effective filtration and adsorption media are used. Filtration and infiltration are used in a wide array of stormwater treatment methods e.g. porous paving, infiltration drains and rain gardens. Several soil minerals were investigated for their potential as stormwater filter materials. Laboratory batch tests were conducted to determine the adsorption capacity of these minerals. A synthetic stormwater was tested, with spiked concentrations corresponding to levels reported in urban runoff, ranging from 50–1,500 µg/L for Zn; 5–250 µg/L for Cu, 2–20 µg/L for Cd and 10–150 µg/L for Ni and Pb. Humic acids were used to imitate natural stormwater contaminated with natural organic matter (NOM). The adsorption kinetics was also investigated through a sequence (10–120 min) of batch tests. By studying the capacity of a range of sorbents in batch tests under identical conditions, the most promising sorbent can be identified. The research is ongoing. Preliminary results will be presented.
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| 11. |
- Björklund, Karin, 1979
(författare)
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Phthalates and Nonylphenols in Stormwater: A Substance Flow Analysis
- 2009
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Ingår i: The International Conference Xenobiotics in the Urban Water Cycle – XENOWAC 2009. ; , s. 6-
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Konferensbidrag (refereegranskat)abstract
- The occurrence of several phthalates and nonylphenol in water environments is highly undesiredbecause of their negative effects on aquatic organisms. The objectives of this study were to identifyemission sources of phthalates, nonylphenol and its ethoxylates (NP/EOs) in urban stormwater, and toquantify the substance fluxes from the source to the stormwater system, using the methodology ofsubstance flow analysis (SFA). The flow analysis showed that phthalates are mainly emitted fromvehicles and coated roofing material, whereas the major NP/EOs sources are vehicles and concrete. It wasestimated that approximately 5.5 kg of four selected phthalates and more than 400 g of NP/EOs areemitted annually to stormwater in the studied area. The SFA approach presented in this study could beapplied in urban catchments of various character to estimate fluxes of unwanted water contaminants.
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| 12. |
- Björklund, Karin, 1979, et al.
(författare)
-
Phthalates and nonylphenols in urban runoff: Occurrence, distribution and area emission factors
- 2009
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 407:16, s. 4665-4672
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Tidskriftsartikel (refereegranskat)abstract
- The urban water system is believed to be an important sink for the nonpoint-source pollutants nonylphenols and phthalates. The presence of nonylphenols (NPs), nonylphenol ethoxylates (NPEOs), and eight phthalates was analyzed in urban stormwater and sediment from three catchment areas in Sweden. Emission loads for these substances were then calculated for a specific urban catchment area. In addition, substance distribution in road runoff passing through a sedimentation facility was modeled using a modified QWASI-model for chemical fate. High concentrations of DEHP, DIDP and DINP (≤ 48, 66 and 200 µg/g dw, respectively) as well as nonylphenol mono- and di-ethoxylate (6.6 and 20 µg/g dw, respectively) were found in the sediment. Aqueous concentrations of the pollutants varied considerably; branched NP was detected in concentrations up to 1.2 µg/L, whereas di(2-ethylhexyl) phthalate (DEHP), diisodecyl phthalate (DIDP), and diisononyl phthalate (DINP) were the most frequently detected phthalates in concentrations up to 5.0, 17 and 85 µg/L, respectively. The fate modeling demonstrated that predicted substance levels in water agreed well with measured levels, whereas the modeled sediment levels were underestimated. Calculation of catchment area emission factors from an urban highway environment revealed that as much as 2.1 kg of total phthalates and 200 g of NP and NPEOs may be emitted per hectare and year. The results indicate that all monitored phthalates, branched NPs and lower NPEOs are present in Swedish urban water systems. The long-chain phthalates DIDP and DINP are believed to occur at higher concentrations than other phthalates because of their higher environmental persistence and their increasing use in Sweden.
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| 13. |
- Björklund, Karin, 1979, et al.
(författare)
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Removal of organic contaminants in bioretention medium amended with activated carbon from sewage sludge
- 2017
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Ingår i: Environmental Science and Pollution Research. - : Springer Science and Business Media LLC. - 0944-1344 .- 1614-7499. ; 24:23, s. 19167-19180
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Tidskriftsartikel (refereegranskat)abstract
- Bioretention, also known as rain garden, allows stormwater to soak into the ground through a soil-based medium, leading to removal of particulate and dissolved pollutants and reduced peak flows. Although soil organic matter (SOM) is efficient at sorbing many pollutants, amending the bioretention medium with highly effective adsorbents has been proposed to optimize pollutant removal and extend bioretention lifetime. The aim of this research was to investigate whether soil amended with activated carbon produced from sewage sludge increases the efficiency to remove hydrophobic organic compounds frequently detected in stormwater, compared to non-amended soil. Three lab-scale columns (520 cm3) were packed with soil (bulk density 1.22 g/cm3); activated carbon (0.5% w/w) was added to two of the columns. During 28 days, synthetic stormwater—ultrapure water spiked with seven hydrophobic organic pollutants and dissolved organic matter in the form of humic acids—was passed through the column beds using upward flow (45 mm/h). Pollutant concentrations in effluent water (collected every 12 h) and polluted soils, as well as desorbed amounts of pollutants from soils were determined using GC-MS. Compared to SOM, the activated carbon exhibited a significantly higher adsorption capacity for tested pollutants. The amended soil was most efficient for removing moderately hydrophobic compounds (log Kow 4.0–4.4): as little as 0.5% (w/w), carbon addition may extend bioretention medium lifetime by approximately 10–20 years before saturation of these pollutants occurs. The column tests also indicated that released SOM sorb onto activated carbon, which may lead to early saturation of sorption sites on the carbon surface. The desorption test revealed that the pollutants are generally strongly sorbed to the soil particles, indicating low bioavailability and limited biodegradation.
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| 14. |
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| 15. |
- Björklund, Karin, 1979, et al.
(författare)
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Screening of Organic Contaminants in Urban Snow
- 2011
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Ingår i: Water Science and Technology. - : IWA Publishing. - 1996-9732 .- 0273-1223. ; 64:1, s. 206-213
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Tidskriftsartikel (refereegranskat)abstract
- Snowmelt is known to cause peak concentrations of pollutants, which may adversely affectreceiving water quality. High concentrations of metals and suspended solids in snow have beenreported, whereas studies on organic pollutants are rare. This study aims at investigating theoccurrence of anthropogenic organic compounds in urban snow in Gothenburg (Sweden). The mostfrequently detected organic pollutants in the collected snow samples were polycyclic aromatichydrocarbons (PAHs), high molecular-weight phthalates, 4-nonylphenol and 4-t-octylphenol.Brominated flame retardants and chlorinated paraffins were only sporadically detected. In severalsnow samples, the concentrations of specific PAHs, alkylphenols and phthalates were higher thanreported stormwater concentrations and European water quality standards. Pollutant sourceidentification and sustainable management of snow are important instruments for the mitigation oforganic contaminants in the urban environment.
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| 16. |
- Björklund, Karin, 1979, et al.
(författare)
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Screening of organic contaminants in urban snow
- 2010
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Ingår i: Proceedings, 14th International Conference, IWA Diffuse Pollution Specialist Group: Diffuse Pollution and Eutrophication. ; , s. 270-275
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Konferensbidrag (refereegranskat)abstract
- Snowmelt is known to cause peak concentrations of pollutants which may adversely affect receiving water quality. High concentrations in snow have been shown for e.g. metals and suspended solids, whereas studies on organic pollutants are rarely reported. This study aimsat investigating the occurrence of anthropogenic organic compounds in urban snow, and at identifying sources of the pollutants. Snow from sites in Gothenburg, Sweden, was sampled and a range of organic substances was analysed. The most frequently detected organic pollutants in urban snow were polycyclic aromatic hydrocarbons, high molecular-weightphthalates, 4-nonylphenol and 4-octylphenol. Brominated flame retardants and chlorinated paraffins were only sporadically detected. In several snow samples, the concentrations of specific PAHs, alkylphenols and phthalates were higher than reported stormwater concentrations and European water quality standards. Pollutant source identification and sustainable management of snow are important instruments for the mitigation of organic contaminants in the urban environment.
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| 17. |
- Björklund, Karin, 1979, et al.
(författare)
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Simulating organic pollutant flows in urban stormwater: development and evaluation of a model for nonylphenols and phthalates
- 2011
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Ingår i: Water Science and Technology. - : IWA Publishing. - 1996-9732 .- 0273-1223. ; 65:3, s. 508-515
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Tidskriftsartikel (refereegranskat)abstract
- Stormwater-quality models can be useful tools for predicting pollutant loads and identifying sources of contamination. Most models in current use handle pollutants such as metals, nutrients and suspended solids, whereas models including emerging organic contaminants are rare.This study aims at developing and evaluating a model for simulating stormwater flows of two groups of organic pollutants; nonylphenols and phthalates. Sources, emission patterns and environmental fate were examined to create a model framework for the organic contaminants. The model was calibrated using field data from three urban catchments. The results show that the simulated pollutant concentrations are overestimated compared to the measured concentrations, which are often close to or below the analytical detection limit. The high uncertainty and the lowpredictive power of the model may be explained by factors such as incorrect catchment data, lack of knowledge on buildup, washoff and other processes involved in substance fate, and an underreporting of pollutant concentrations in stormwater. More data on release patterns and sewer fate are needed to adequately simulate stormwater concentrations of nonylphenols and phthalates. A conventional substance flow analysis based on bookkeeping, evaluated in parallel to the computer model, has proven to be useful for calculating fluxes of nonylphenols and phthalates in urban catchments.
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| 18. |
- Björklund, Karin, 1979, et al.
(författare)
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Sorption of DOM and hydrophobic organic compounds onto sewage-based activated carbon
- 2016
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Ingår i: Water Science and Technology. - : IWA Publishing. - 1996-9732 .- 0273-1223. ; 74:4, s. 852-860
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Tidskriftsartikel (refereegranskat)abstract
- Treatment of stormwater via sorption has the potential to remove both colloidal and dissolved pollutants. Previous research shows that activated carbon produced from sewage sludge is very efficient in sorbing hydrophobic organic compounds (HOCs), frequently detected in stormwater. The aim of this research was to determine whether the presence of dissolved organic matter (DOM) has a negative effect on the adsorption of HOCs onto sludge-based activated carbon (SBAC) in batch adsorption tests. Batch adsorption tests were used to investigate the influence of two types of DOM – soil organic matter and humic acid (HA) technical standard – on the sorption of HOCs onto SBAC, and whether preloading adsorbent and adsorbates with DOM affects HOC sorption. The results indicate that soil DOM and HAs do not have a significant negative effect on the adsorption of HOCs under tested experimental conditions, except for a highly hydrophobic compound. In addition, preloading SBAC or HOCs with DOM did not lead to lower adsorption of HOCs. Batch adsorption tests appear to be inefficient for investigating DOM effects on HOC adsorption, as saturating the carbon is difficult because of high SBAC adsorption capacity and low HOC solubility, so that limited competition occurs on the sorbent.
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| 19. |
- Björklund, Karin, 1979, et al.
(författare)
-
Sorption of organic contaminants and nutrients onto rain garden soil amended with activated carbon
- 2017
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Ingår i: Conference Proceedings, 14th IWA/IAHR International Conference on Urban Drainage; September 10-15, 2017; Prague, Czech Republic. ; , s. 1060-1064
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Konferensbidrag (refereegranskat)abstract
- Raingardens may improve stormwater quality e.g. through pollutant sorption to soil. The aimof this study was to determine if adding activated carbon, a highly efficient sorbent, to rain garden soil can enhance the removal of organic pollutants and nutrients. Batch tests show that the activated carbon is efficient in sorbing hydrophobic organic pollutants, nitrate and phosphate. However, only the organic pollutants are removed in column tests where the activated carbon is mixed with soil. The low adsorption of nutrients in column experiments is likely due to competition for adsorption sites on the carbon surface with organic matter leached from the soil.
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| 20. |
- Björklund, Karin, 1979, et al.
(författare)
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Sorption of organic pollutants frequently detected in stormwater: evaluation of five potential sorbents
- 2018
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Ingår i: Environmental Technology (United Kingdom). - : Informa UK Limited. - 1479-487X .- 0959-3330. ; 39:18, s. 2335-2345
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Tidskriftsartikel (refereegranskat)abstract
- Adsorption filtration is one of the most promising techniques for removal of dissolved, colloidal and particulate pollutants from stormwater. The aim of this study was to compare the capacity of five filter materials – cellulose, chitosan, chitosan-covered bark, pine bark and polypropylene/polyethylene (PP/PE) fibres – to sorb organic pollutants frequently detected in stormwater, including polycyclic aromatic hydrocarbons (PAHs), alkylphenols and phthalates. In batch tests, synthetic stormwater spiked with a mixture of the organic compounds was contacted with the materials for up to 24 h. The compounds were then liquid–liquid extracted and analysed using GC-MS. Cellulose and chitosan showed very low sorption capacity for the organic contaminants, whereas >70% of the initial concentration of most tested compounds was removed using PP/PE fibres, and >80% with pine bark and chitosan-covered bark. The highest adsorption capacity was found for PAHs (up to 44 μg/g) using PP/PE fibres and bark. For all tested compounds, maximum sorption was approached within 30 min using these materials.
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| 21. |
- Björklund, Karin, 1979
(författare)
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Sources and fluxes of organic contaminants in urban runoff
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Urban runoff quality is recognized as one of the most significant pressures on aquatic ecosystems worldwide. Research into pollutants in urban runoff has traditionally focused on nutrients, suspended solids and metals and consequently knowledge of anthropogenic organic pollutants is limited. The aim of this research was to investigate the occurrence and identify the sources of certain selected organic contaminants in urban runoff, and to evaluate tools for predicting the fluxes of these pollutants in urban catchment areas. Alkylphenols and phthalates were selected for further study since they are used in large quantities and emissionsof these compounds are likely to end up in urban runoff.The occurrence of alkylphenols and phthalates was investigated in urban snow, stormwater and sediment. In general, 4-nonylphenol showed high concentrations and detection frequencies compared to most other alkylphenols. Among the phthalates, diisononyl phthalate (DINP) was detected at the highest concentrations in all matrices, followed by diisodecyl phthalate (DIDP) and di(2-ethylhexyl) phthalate (DEHP). Nonylphenol, octylphenol and DEHP were repeatedly detected in stormwater and snow at concentrations exceeding the European water quality standards. This suggests that measures to reduce the discharge of anthropogenic substances to urban areas are necessary to achieve good water status. Substance flow analysis (SFA) was used to map the sources and quantify the loads of phthalates and nonylphenols in urban catchment areas. The calculated loads of thecontaminants were in agreement with measured loads in a studied catchment area and SFA was thus considered efficient for identifying the most important sources of phthalates and nonylphenols. The emission factors used in the calculation of the pollutant loads were also used in a process-based stormwater quality model for predicting nonylphenol and phthalate concentrations in runoff. The model revealed low predictive power; the simulatedconcentrations were generally one magnitude higher than the measured concentrations. In future studies, it is recommended to link the outcomes from the SFA to a fate model. This integrated model would provide a holistic overview of the sources and sinks of pollutants in urban catchment areas and could be used to evaluate both source control and end-of-pipe mitigation practices.
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| 22. |
- Björklund, Karin, 1979
(författare)
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Substance flow analyses of phthalates and nonylphenols in stormwater
- 2010
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Ingår i: Water Science and Technology. - : IWA Publishing. - 1996-9732 .- 0273-1223. ; 62:5, s. 1154-1160
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Tidskriftsartikel (refereegranskat)abstract
- The occurrence of nonylphenol and several phthalates in water environments is highly undesired because of their negative effects on aquatic organisms. The objectives of this study were to identify emission sources of phthalates, nonylphenol and its ethoxylates (NP/EOs) in urban stormwater, and to quantify the substance fluxes from the source to the stormwater system, using the methodology of substance flow analysis (SFA). The SFA, applied on an urban motorway area, showed that phthalates are mainly emitted from vehicles and coated roofing material, whereas the major NP/EOs sources are vehicles and concrete. It was estimated that approximately 4.1 kg of four selected phthalates and more than 400 g of NP/EOs are emitted annually to stormwater in the studied area. The SFA approach presented in this study, using factors that express the emission rate of a specific substance from a specific source, could be applied in urban catchments of various character to estimate fluxes of water contaminants.
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| 23. |
- Björklund, Karin, 1979, et al.
(författare)
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Using the stormwater-quality model SEWSYS to identify sources and fluxes of hazardous organic substances
- 2008
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Ingår i: Book of abstracts. 9th Highway and Urban Environment Symposium, 9-11 June 2008, Madrid, Spain. ; , s. 21-
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Konferensbidrag (refereegranskat)abstract
- Stormwater-quality models simulating pollutant pathways in urban catchments are proven to be valuable means when planning and evaluating appropriate strategies to reduce the detrimental impacts of urban runoff [Zoppou, 2001]. SEWSYS, a substance flow model simulating pollutant concentrations in stormwater, is an effective instrument for predicting pollution loads from non-point sources and can therefore be used for proposing measures to reduce the release of contaminants into the environment [Ahlman, 2006]. SEWSYS is now being expanded from operating with nutrients and metals, to include also a few organic substances. In this study, two groups of organic compounds – phthalates and nonylphenols (NPs) – were selected for an initial flow analysis. These compounds, classified as “very toxic to aquatic organisms” [KEMI, 2007a], are high volume chemicals used as additives in a variety of products [KEMI, 2007b]. To incorporate phthalates and NPs into SEWSYS, an extensive literature study was accomplished. The study included identification of potential pollutant sources in urban areas, e.g. building materials and vehicles, and analysis of emission patterns and rates. Also, model input data such as source distribution and authentic rain series were collected from three urban catchment areas. Simulated pollutant concentrations were then compared with measured and analysed concentrations in stormwater from the investigated catchments. Preliminary model simulations showed that pollutant loadings and major contributing sources are catchment dependent: e.g. vehicles are the dominant sources of phthalates in traffic areas whereas construction materials are the most important sources in residential areas. These simulation results were then used for proposing adequate measures in order to mitigate phthalate and NP loads in stormwater. Calculations showed that by using phthalate- or NP-free construction materials, and by reducing the traffic load, the pollution load from residential and traffic areas was considerably decreased. These findings illustrate the use of SEWSYS as a tool for improving urban runoff quality, and corresponding simulations could easily be performed by local authorities for planning of effective abatement strategies. ReferencesAhlman S (2006) Modelling of Substance Flows in Urban Drainage Systems. Doctoral Thesis, Department of Civil and Environmental Engineering, Chalmers University of Technology, Göteborg, Sweden.KEMI (Swedish Chemicals Agency). (2007a) Classification List. http://apps.kemi.se/klassificeringslistan/default.cfmKEMI (Swedish Chemicals Agency). (2007b) KemI-Stat. http://apps.kemi.se/kemistat/start.aspx?sprak=eZoppou C (2001) Review of urban storm water models. Environmental Modelling & Software 16 (3), 195-231.
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| 24. |
- Bondelind, Mia, 1980, et al.
(författare)
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Hydrodynamic modelling of traffic-related microplastics discharged with stormwater into the Göta River in Sweden
- 2020
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Ingår i: Environmental Science and Pollution Research. - : Springer Science and Business Media LLC. - 0944-1344 .- 1614-7499. ; 27:19, s. 24218-24230
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Tidskriftsartikel (refereegranskat)abstract
- Microplastics (MP) are transported from land-based sources from rivers to marine waters. However, there is currently little knowledge about MP fate from land sources to marine waters. Traffic is estimated to be one of the largest sources of MP; hence, stormwater is expected to be an important transportation route of MP to marine waters. The aim of this study was to investigate the effect of the size and density of tyre wear particles in road run-off on their fate in the Gota River in Sweden using hydrodynamic modelling. The model of the stretch of Gota River, Sweden's largest river, passing through Gothenburg (Sweden's second largest city) and out to the sea, was set up using MIKE 3 FM software. Literature data were used to define the MP characteristics: concentrations in stormwater, prevalent particle sizes, density of MP commonly occurring in road run-off and settling velocities. Results show that higher concentrations of MP are found on the south side of the river, compared with the north side, due to higher annual average daily traffic loads along the south side of the river. The mixing processes in the river and the MP concentrations were generally influenced by the vertical water density gradient caused by saline water from the Kattegat strait. While most MP with higher density and larger size settle in the river, smaller MP with density close to 1.0 g/cm(3) do not settle in the river and therefore reach the Kattegat strait and the marine environments. Further research is needed to describe the fate and transport of microplastics in the stormwater system, including treatment facilities, i.e. biofouling, aggregation, degradation and/or further fragmentation and settling.
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| 25. |
- Bondelind, Mia, 1980, et al.
(författare)
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Influence of stormwater and CSOs on copper and benzo[a]pyrene in receiving waters – hydrodynamic modelling approach
- 2017
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Ingår i: Conference Proceedings, 14th IWA/IAHR International Conference on Urban Drainage, September 10-15, 2017, Prague, Czech Republic. ; , s. 540-543
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Konferensbidrag (refereegranskat)abstract
- In this study the influence of urban stormwater discharges and combined sewer overflows on receiving water was investigated in the context of chemical risks and recreational water quality. Transport of copper and benzo[a]pyrene in the Göta River, running through the city of Gothenburg (Sweden), was simulated using a hydrodynamic model. The modelling results showed that during rain events the water quality along the river deteriorates for different periods of time, at times exceeding the guideline values established by the city of Gothenburg. The model can be used as an effective tool to prognosticate the water quality in the river.
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| 26. |
- Bondelind, Mia, 1980, et al.
(författare)
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Transport of Traffic-Related Microplastic Particles in Receiving Water
- 2019
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Ingår i: Green Energy and Technology. - Cham : Springer International Publishing. - 1865-3529 .- 1865-3537. - 9783319998664 ; , s. 317-321
-
Konferensbidrag (refereegranskat)abstract
- A majority of microplastic particles (MPs) in marine waters are transported with rivers from land-based sources. Traffic is estimated to be one of the largest sources of MPs, hence stormwater and subsequently urban waterways are expected to be important transportation routes of MPs to marine waters. However, there is currently little knowledge about MP fate from land sources to marine waters. The aim of this study is to investigate the transport of traffic-related microplastic particles in a receiving freshwater body using hydrodynamic modelling. A model of a 16 km stretch of the Göta River, Sweden’s largest river, was set up using MIKE 3 FM software. The model builds on data on water flows in the river and its tributaries, water levels and salinity stratification in the Kattegat strait, and meteorological conditions. Concentrations of MPs in stormwater and MP characteristics data, including prevalent particle sizes, density of commonly occurring polymers, and settling velocities were found in the literature. The simulations show that peak concentrations of MPs exhibit a short duration; however, elevated concentrations of MPs may be present for hours after discharge into the river. The simulations indicate that MPs do not settle at the bottom of the river bed; this scenario can be expected for low density MPs including tyre rubber, as well as larger particles (≤ 5 mm) of higher density (> 1 g/cm3). Hence, a high load of MPs from the city of Gothenburg will reach the marine environment. Biofouling and MPs adhering to mineral particles, as has been shown in marine waters, may considerably change the characteristics of MPs and should be considered in future studies.
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| 27. |
- Järlskog, Ida, 1991, et al.
(författare)
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Traffic-related microplastic particles, metals, and organic pollutants in an urban area under reconstruction
- 2021
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 774
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Tidskriftsartikel (refereegranskat)abstract
- In urban environments, particularly areas under reconstruction, metals, organic pollutants (OP), and microplastics (MP), are released in large amounts due to heavy traffic. Road runoff, a major transport route for urban pollutants, contributes significantly to a deteriorated water quality in receiving waters. This study was conducted in Gothenburg, Sweden, and is unique because it simultaneously investigates the occurrence of OP, metals, and MP on roads and in stormwater from an urban area under reconstruction. Correlations between the various pollutants were also explored. The study was carried out by collecting washwater and sweepsand generated from street sweeping, road surface sampling, and flow-proportional stormwater sampling on several occasions. The liquid and solid samples were analyzed for metals, polycyclic aromatic hydrocarbons (PAH), oxy-PAH, aliphatics, aromatics, phthalates, and MP. The occurrence of OP was also analyzed with a non-target screening method of selected samples. Microplastics, i.e. plastic fragments/fibers, paint fragments, tire wear particles (TWP) and bitumen, were analyzed with a method based on density separation with sodium iodide and identification with a stereo microscope, melt-tests, and tactile identification. MP concentrations amounted to 1500 particles/L in stormwater, 51,000 particles/L in washwater, and 2.6 × 106 particles/kg dw in sweepsand. In stormwater, washwater and sweepsand, MP ≥20 μm were found to be dominated by TWP (38%, 83% and 78%, respectively). The results confirm traffic as an important source to MP, OP, and metal emissions. Concentrations exceeding water and sediment quality guidelines for metals (e.g. Cu and Zn), PAH, phthalates, and aliphatic hydrocarbons in the C16–C35 fraction were found in most samples. The results show that the street sweeper collects large amounts of polluted materials and thereby prevents further spread of the pollutants to the receiving stormwater.
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| 28. |
- Kalmykova, Yuliya, 1981, et al.
(författare)
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Partitioning of Polycyclic Aromatic Hydrocarbons, Alkylphenols, Bisphenol A and Phthalates in Landfill Leachates and Stormwater.
- 2013
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Ingår i: Water Research. - : Elsevier BV. - 0043-1354 .- 1879-2448. ; 47:3, s. 1317-1328
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Tidskriftsartikel (refereegranskat)abstract
- Partitioning of organic pollutants is essential to their fate, mobility and removal from water and soil. To study the partitioning behavior of selected alkylphenols, bisphenol A, phthalates and polycyclic aromatic hydrocarbons (PAHs), a method for separating the truly dissolved and colloidal phase of organic pollutants was developed, verified and applied to samples of landfill leachate and stormwater from urban areas and waste-sorting sites.Alkylphenols, bisphenol A, phthalates and PAHs were detected in all the untreated samples (total concentrations), most of the filtered samples and frequently in the colloid-bound phase. Concentrations of alkylphenols and PAHs in urban stormwater were one order of magnitude lower than in the landfill leachates and stormwater from waste-sorting sites.The difference between total, dissolved and colloid-bound concentrations in the water samples was not statistically significant for any phenols or phthalates, but for three of the PAHs; naphthalene (mostly dissolved), phenanthrene and fluoranthene (mostly particulate). These results indicate that in landfill leachates and stormwaters, organic pollutants are predominantly attached to colloids and/or truly dissolved in contrast to their expected strong sorption to particulate matter. Occurrence and concentrations of pollutants in dissolved and colloid-bound phases correlated negatively with the KOW. However, even highly hydrophobic compounds were frequently detected in filtered samples, i.e. the dissolved phases, and it is suggested that the organic content in the colloids decreases the compounds' partition to particles. The results confirm that the KOW values of specific organic pollutants well describe the compounds partition-binding process to dissolved organic carbon (DOC) colloids. Our findings call for a re-assessment of the organic pollutants' mobility and associated risks. This knowledge can also serve as a base for selecting efficient treatment methods for stormwater and landfill leachates.
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| 29. |
- Kalmykova, Yuliya, 1981, et al.
(författare)
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Sorption and degradation of petroleum hydrocarbons, polycyclic aromatic hydrocarbons, alkylphenols, bisphenol A and phthalates in landfill leachate using sand, activated carbon and peat filters
- 2014
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Ingår i: Water Research. - : Elsevier BV. - 0043-1354 .- 1879-2448. ; 56, s. 246-257
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Tidskriftsartikel (refereegranskat)abstract
- Landfill leachates are repeatedly found contaminated with organic pollutants, such as alkylphenols (APs), phthalates and polycyclic aromatic hydrocarbons (PAHs) at levels exceeding water quality standards. It has been shown that these pollutants may be present in the colloidal and truly dissolved phase in contaminated water, making particle separation an inefficient removal method. The aim of this study was to investigate sorption and degradation of petroleum hydrocarbons (PHCs), selected APs, bisphenol A (BPA), phthalates and PAHs from landfill leachate using sand, granulated activated carbon (GAC) and peat moss filters. A pilot plant was installed at an inactive landfill with mixed industrial and household waste and samples were collected before and after each filter during two years.Leachate pre-treated in oil separator and sedimentation pond failed to meet water quality standards in most samples and little improvement was seen after the sand filter. These techniques are based on particle removal, whereas the analysed pollutants are found, to varying degrees, bound to colloids or dissolved. However, even highly hydrophobic compounds expected to be particle-bound, such as the PHCs and high-molecular weight PAHs, were poorly removed in the sand filter. The APs and BPA were completely removed by the GAC filter, while mass balance calculations indicate that 50–80% of the investigated phenols were removed in the peat filter. Results suggest possible AP degradation in peat filters. No evidence of phthalate degradation in the landfill, pond or the filters was found. The PHCs were completely removed in 50% and 35% of the measured occasions in the GAC and peat filters, respectively. The opposite trend was seen for removal of PAHs in GAC (50%) and peat (63%). Oxygenated PAHs with high toxicity were found in the leachates but not in the pond sediment. These compounds are likely formed in the pond water, which is alarming because sedimentation ponds are commonly used treatment techniques. The oxy-PAHs were effectively removed in the GAC, and especially the peat filter. It was hypothesized that dissolved compounds would adsorb equally well to the peat and GAC filters. This was not completely supported as the GAC filter was in general more efficient than peat.
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| 30. |
- Lindberg, R. H., et al.
(författare)
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Environmental risk assessment of antibiotics in the Swedish environment with emphasis on sewage treatment plants
- 2007
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Ingår i: Water Research. - : Elsevier BV. - 0043-1354 .- 1879-2448. ; 41:3, s. 613-619
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Tidskriftsartikel (refereegranskat)abstract
- The potential risks associated with antibiotics present in the Swedish environment were assessed using concentrations found in hospital effluent, and sewage treatment waters and sludge, in combination with data on their environmental effects obtained from the literature. For the aqueous environment, measured environmental concentrations and effect/no observed effect concentration ratios were much lower than one in most cases. The only exceptions, where concentrations of the investigated substances were high enough to pose potential risks, were the concentrations of the two fluoroquinolones, ofloxacin and ciprofloxacin, in the hospital effluent. Treating digested dewatered sludge by heat did not fully eliminate norfloxacin or ciprofloxacin, thus pellets may still contain high amounts of these substances (sub to low mg kg(-1) dw). In leaching tests less than 1% of the amounts of these fluoroquinolones in the sludge or pellets reached the aqueous phase, indicating that their mobility is limited if sludge is used to fertilize soil. (c) 2006 Elsevier Ltd. All rights reserved.
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| 31. |
- Markiewicz, Anna, 1984, et al.
(författare)
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A pilot study of sorption filters to remove non-particulate organic pollutants in stormwater
- 2017
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Ingår i: Proceedings of International Conference on Urban Drainage.
-
Konferensbidrag (refereegranskat)abstract
- Organic pollutants (OPs) occur in urban stormwater as sorbed to particles, and in dissolved and colloidal forms. In this study, a pilot plant with column bed-filters of sand in combination with granulated activated carbon (GAC), peat and bark was used to investigate the removal of non-particulate OPs from stormwater. Bark, peat and GAC filters showed 60-100% reduction of aliphatics, aromatics and naphthalene when incoming water was spiked with contaminated sediment and diesel, and the peat filter showed 70% reduction of aromatics and naphthalene during heavy rain events. Sufficient water flows through the filters were difficult to achieve and improvements of the hydraulics are recommended.
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| 32. |
- Markiewicz, Anna, 1984, et al.
(författare)
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Alternative sorption filter materials effectively remove non-particulate organic pollutants from stormwater
- 2020
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 730
-
Tidskriftsartikel (refereegranskat)abstract
- Urban runoff contains a mixture of both particulate and non-particulate organic pollutants (OPs). Hydrophobic OPs such as higher petroleum hydrocarbons, phthalates, and polycyclic organic hydrocarbons (PAHs) are not exclusively bound to particles, but also present in runoff in colloidal and truly dissolved forms. These hydrophobic compounds can also form nano- and microsized emulsions that may carry pollutants in stormwater. Hence, it is of great importance to develop treatment technologies such as sorption filters that can remove non-particulate OPs from contaminated stormwater. A pilot plant using column bed-filters of sand as a pre-filter, in combination with granulated activated carbon, Sphagnum peat or Pinus sylvestris bark, was used to investigate the removal of non-particulate OPs from urban stormwater. Samples from the filter effluents were collected weekly; during or after rain events; and during stress tests when incoming water was spiked with contaminated sediment and petrol or diesel. All sorption filters showed efficient reduction of aliphatic diesel hydrocarbons C16–C35, benzene, and the PAHs phenanthrene, fluoranthene, and pyrene during most of the operation time, which was 18 months. During the stress test events, all sorption filters showed 100% reduction of PAH-16, petrol and diesel aliphatics C5–C35. All sorption filters released DOC and nanoparticles, which may explain some of the transportation of OPs through the filter beds. The recommendation is to use a combination of sand pre-filtration and all the studied sorption materials in stormwater filters in series, to achieve effective removal of different types of OPs. It is also important to improve the hydraulic conditions to obtain sufficient water flows through the filters.
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| 33. |
- Markiewicz, Anna, 1984, et al.
(författare)
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Emissions of organic pollutants from traffic and roads : Priority pollutants selection and substance flow analysis
- 2017
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Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 580, s. 1162-1174
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Tidskriftsartikel (refereegranskat)abstract
- A large number of organic pollutants (OPs) emitted from vehicles and traffic-related activities exhibit environmental persistence and a tendency to bioaccumulate, and may have detrimental long-term effects on aquatic life. The aim of the study was to establish a list of significant sources of OPs occurring in road runoff, identify the OPs emitted from these sources, select a number of priority pollutants (PP), and estimate the quantity of PPs emitted in a road environment case study using substance flow analysis (SFA). The priority pollutants included in the SFA were selected from a list of approximately 1100 compounds found after comprehensive screening, including literature and database searches, expert judgments, the Ranking and Identification of Chemical Hazards method, and chemical analysis of sediments. The results showed the following priority order: polycyclic aromatic hydrocarbons (PAHs) > alkanes C20–C40 > alkylphenols > phthalates > aldehydes > phenolic antioxidants > bisphenol A > oxygenated-PAHs > naphtha C5–C12 > amides > amines. Among these, PAHs were chosen for a SFA, which was performed for a highway case study area in Gothenburg (Sweden). The SFA showed that the main sources of PAHs emitted in the area were vehicle exhaust gases, followed by tyre wear, motor lubricant oils, road surface wear, and brake linings. Only 2–6% of the total 5.8–29 kg annually emitted PAHs/ha ended up in the stormwater sewer system. The measured PAH loads were found in much smaller amounts than the calculated loads and the outflow to stormwater contained much more of the hazardous PAHs than the total loads emitted in the catchment area.
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| 34. |
- Markiewicz, Anna, 1984, et al.
(författare)
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Generation of nano- and micro-sized organic pollutant emulsions in simulated road runoff
- 2019
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Ingår i: Environment International. - : Elsevier. - 0160-4120 .- 1873-6750. ; 133, s. 1-12
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Tidskriftsartikel (refereegranskat)abstract
- A wide range of organic pollutants (OPs) are emitted from the road and traffic environment and transported with road runoff to receiving waters. To provide an understanding of the transport routes of OPs in the environment, an investigation was carried out with the aim to determine whether OPs are transported with nano- and microparticles in the form of emulsions. Tests were performed on simulated road runoff, using laboratory prepared mixtures of ultrapure water and specific polycyclic aromatic hydrocarbons (PAHs), alkylphenols (APs) and their ethoxylates (APEOs), phthalates, diesel oil (aliphatic hydrocarbons), with and without addition of humic acid (HA) and iron (Fe) colloids. The samples were analysed directly after mixing and after a few days of stabilisation for particle size distribution (PSD) and concentrations of particles in the size range 10 nm-100 mu m, and zeta potential> +/- 500 mV. Further, after long-term storage to achieve stabilisation, selected samples were investigated for the PSD and particle concentrations in the ranges 10 nm-2 mu m, to determine whether stable emulsions had formed. The following simulation mixtures, both mixed and stabilised, were identified as potential emulsions: diesel, APs and APEOs, diesel with APs and APEOS, phthalates, and a mixture of all OPs with and without colloids. Measurements with the Zetasizer and Nanosight instruments imply that the majority of particles in the samples were found in the nano-range of 30-660 nm respectively, and a smaller portion of particles < 28% also measured with Coulter Counter were found to be micro-sized. Higher concentrations of the smallest nanoparticles were found in the mixture of all OPs without colloids added, than in the OP mixture with colloids added. The results indicate that the addition of colloids favours the formation of larger micro-sized emulsions that may break down with time into nano-sized particles. In the mixed samples, the number of micro-sized particles decreased, while the number of nanoparticles increased; this process may also occur in road runoff transportation systems during heavy rain events. This is the first study to indicate that emulsions of OPs may be formed in road runoff, and that emulsions may act as carriers of OPs in urban stormwater.
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| 35. |
- Polukarova, Maria, 1992-, et al.
(författare)
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Organic pollutants, nano- and microparticles in street sweeping road dust and washwater
- 2020
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Ingår i: Environment International. - : Elsevier BV. - 0160-4120 .- 1873-6750. ; 135
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Tidskriftsartikel (refereegranskat)abstract
- Road areas are pollution hotspots where many metals, organic pollutants (OPs) and nano/microparticles accumulate before being transported to receiving waters. Particles on roads originate from e.g. road, tyre and vehicle wear, winter road maintenance, soil erosion, and deposition. Street sweeping has the potential to be an effective and affordable practice to reduce the occurrence of road dust, and thereby the subsequent spreading of pollutants, but there is currently little knowledge regarding its effectiveness. In this paper we investigate the potential of street sweeping to reduce the amounts of OPs and nano/microparticles reaching stormwater, in a case study sampling road dust and washwater from a street sweeping machine, road dust before and after sweeping, and stormwater. The compound groups generally found in the highest concentrations in all matrices were aliphatics C5–C35 > phthalates > aromatics C8–C35 > PAH-16. The concentrations of aliphatics C16–C35 and PAHs in washwater were extremely high at ≤ 53,000 µg/L and ≤ 120 µg/L, respectively, and the highest concentrations were found after a 3-month winter break in sweeping. In general, fewer aliphatic and aromatic petroleum hydrocarbons and PAHs were detected in road dust samples than in washwater. The relative composition of the specific PAH-16 suggests tyre wear, vehicle exhausts, brake linings, motor oils and road surface wear as possible sources. The study indicates that many of the hydrophobic compounds quantified in washwater are attached to small particles or truly dissolved. The washwater contains a wide range of small particles, including nanoparticles in sizes from just below 1 nm up to 300 nm, with nanoparticles in the size range 25–300 nm present in the highest concentrations. The results also indicated agglomeration of nanoparticles in the washwater. The street sweeping collected a large amount of fine particles and associated pollutants, leading to the conclusion that washwater from street sweeping needs to be treated before disposal.
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