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  • 1.
    Müller, Alexandra
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordqvist, Kerstin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Marsalek, Jiri
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Building surface materials as sources of micropollutants in building runoff: A pilot study2019In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 680, p. 190-197Article in journal (Refereed)
    Abstract [en]

    Control of diffuse pollution is critical for achieving good surface water quality status. In this context, pollutant contributions from building materials have received increased attention in recent decades. This study examined the releases of metals, nonylphenols and phthalates from ten common building surface materials (installed in triplicates) into rainwater runoff from six rain events. The highest releases of metals were from copper and zinc sheets (average concentrations of 3090 μg/L Cu and 7770 μg/L Zn respectively), while other metal materials, e.g., Corten weathering steel, exhibited lower releases. PVC roofing released high concentrations of nonylphenols and phthalates (average concentrations of up to 26 μg/L nonylphenols and 455 μg/L Diisononyl phthalate, DINP) which have not been investigated in the earlier studies. Pollutant releases varied between events, likely because of weather conditions and rainfall characteristics. Study findings should be valuable for environmentally responsible applications of the existing building materials and the development of new ones, as well as the investigations and risk assessment of specific pollutants in stormwater.

  • 2.
    Lindfors, Sarah
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Heléne
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Meyn, Thomas
    Muthanna, Tone Merete
    Lundy, Lian
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Characterisation of Dissolved Metal Fractions in Urban Runoff2019Conference paper (Other academic)
  • 3.
    Viklander, Maria
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water. Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Müller, Alexandra
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Marsalek, Jiri
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Borris, Matthias
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Kunskapssammanställning: Dagvattenkvalitet2019Report (Other (popular science, discussion, etc.))
    Abstract [en]

    This report summarizes stormwater pollutants, their sources, concentrations, and variations in concentrations. Practical guidance for field data collection, adoption of standard data from the literature and computer modelling are given. Furthermore, the effects on health, the environment and society, and associated regulations are discussed.

  • 4.
    Vijayan, Arya
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Marsalek, Jiri
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Laboratory Melting of Late-Winter Urban Snow Samples: The Magnitude and Dynamics of Releases of Heavy Metals and PAHs2019In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 230, no 8, article id 182Article in journal (Refereed)
    Abstract [en]

    Laboratory snow melting experiments were conducted with actual late-winter snow samples, collected just before the final snowmelt, in two similar northern Swedish cities, Luleå and Umeå, to investigate releases of the selected heavy metals (HM) (Cu, Pb, Zn, and Cd) and 16 USEPA PAHs from melting snow. Metal concentrations were determined in three fractions: total, dissolved, and truly dissolved (defined as the fraction passing through a 3-kMWCO ultrafilter). Total HM concentrations in snowmelt were rather high at both sites and reflected the accumulation of pollutants in the roadside snowbanks over a period of about 5 months: Cd = 0.43, Cu = 303, Pb = 41.9, Zn = 817 (μg/l), and TSS = 2000 (mg/l) in Luleå samples and Cd = 1.87, Cu = 905, Pb = 165, Zn = 3150 (μg/l), and TSS = 4800 (mg/l) in Umeå samples. The difference between metal and TSS concentrations at the two sites of similar characteristics was attributed to a smaller volume snowbank in Umeå. The dissolved HM concentrations represented relatively small fractions of the total concentrations (0.3–6.9% in Luleå and 0.01–3.1% in Umeå). The truly dissolved fraction represented 71–90% of the dissolved fraction in Luleå and 74–98% in Umeå. At both sites, the dissolved fractions exhibited preferential elution from the laboratory snow piles. The PAHs studied (16 US EPA PAHs) were mostly particulate bound, with only 5–12% of the total burden contributed by the meltwater, and most dissolved concentrations below the reporting limits. PAH concentrations in the Luleå samples were about one-third to one-fourth of those in Umeå. In general, the releases of PAHs from the snowbank were delayed, compared with releases of meltwater, and showed similar release patterns as TSS.

  • 5.
    Gavric, Snezana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Larm, Thomas
    StormTac corporation, Stockholm, Sweden.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Marsalek, Jiri
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Wahlsten, Anna
    StormTac corporation, Stockholm, Sweden.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Measurement and conceptual modelling of retention of metals (Cu, Pb, Zn) in soils of three grass swales2019In: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707, Vol. 574, p. 1053-1061Article in journal (Refereed)
    Abstract [en]

    Grass swales are important elements of the urban green infrastructure that convey and attenuate urban runoff and improve its quality mostly through stormwater infiltration into, and retention of conveyed pollutants by, swale soils. The retention of metals by grass swales was addressed in this study investigating the enrichment of swale soils by three common traffic-related metals: Cu, Pb and Zn. Three swales of various characteristics (L1, L2, L3) were selected for study and their soils were sampled by coring the top 30 cm and dividing the cores into 5 cm thick layers. Cumulative metal burdens were compared to those modelled by the proprietary StormTac Web model, which estimates annual loads of specific constituents for the given land uses and stormwater treatment. The comparisons of measured (MBm) and simulated (MBs) metal burdens retained by swales showed that the measured values exceed the simulated ones, as described by average ratios MBs/MBm = 0.64, 0.50 and 0.59, for swales L1, L2 and L3, respectively. The measured burdens were calculated after subtracting the native soil metal concentrations, assumed equal to those found in the deepest sampled layer, 25–30 cm below the surface. The results suggest the feasibility of assessing performance of grass swales by modelling metal (Cu, Pb, Zn) retention by swales, however for older facilities considered for rehabilitation, the simulated results should be supplemented by soil chemistry sampling.

  • 6.
    Gavric, Snezana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Larm, Thomas
    StormTac AB, Stockholm.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Marsalek, Jiri
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Wahlsten, Anna
    StormTac AB, Stockholm.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Measurement and Planning–Level Modelling of Retention of Trace Metals (Cu, Pb, Zn) in Soils of Three Urban Drainage Grass Swales2019In: New Trends in Urban Drainage Modelling: UDM 2018 / [ed] Giorgio Mannina, Cham: Springer, 2019, p. 85-90Conference paper (Refereed)
    Abstract [en]

    Grass swales are important elements of urban green infrastructure that convey, attenuate and improve the quality of urban runoff mostly through stormwater infiltration into and retention of conveyed pollutants by swale soils. Such processes were addressed in this study, investigating the enrichment of swale soils by ubiquitous urban trace metals, Cu, Pb and Zn. Three swales were selected for study in the City of Lulea (Northern Sweden) and their soils were sampled by coring. Sample cores covered soil depths up to 30 cm, but only the results from the top 5 cm layer characterized by 9–15 samples in each swale are discussed here. After estimating metal mass in this layer in individual swales, such burdens were compared to those modelled by the proprietary StormTac Web model, which estimates annual loads of specific constituents for given land uses and is supported by an extensive database referenced to Swedish environmental conditions. The annual loads modelled for individual swales were multiplied by the swale age to obtain long–term inputs of the trace metals. A good agreement between the measured and modelled loads in soils was obtained and characterized by the ratio Lmod/Lmeas, with an average value of 0.96 and standard deviation of 0.55. Such results suggest the feasibility of assessing the long–term performance of grass swales by modelling trace metal (Cu, Pb, Zn) inputs into swales, estimating the metal loads retained in soils by sampling and analyses, and taking the difference (Lin − Lret) as the exported load.

  • 7.
    Tondera, Katharina
    et al.
    Institute of Environmental Engineering, RWTH Aachen University, Aachen.
    Blecken, Godecke-Tobias
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Tournebize, Julien
    Hydrosystems and Bioprocessus Research Unit, Irstea—National Research Institute of Science and Technology for Environment and Agriculture, Antony.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Andersson-Wikström, Alexandra
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Tanner, Chris C.
    National Institute of Water and Atmospheric Research, Hamilton.
    Emerging Contaminants: Occurrence, Treatment Efficiency and Accumulation Under Varying Flows2018In: Ecotechnologies for the Treatment of Variable Stormwater and Wastewater Flows / [ed] Katharina Tondera, Godecke-Tobias Blecken, Florent Chazarenc, Chris C. Tanner, Cham: Springer, 2018, p. 93-109Chapter in book (Refereed)
    Abstract [en]

    Emerging contaminants became a major topic in water treatment when laboratory detection methods for concentrations at a nanogram-scale improved approximately two decades ago. Research on using ecotechnologies to remove emerging contaminants in variable stormwater and wastewater flows has been conducted for more than a decade, but so far, not all removal mechanisms are well understood and only few setups have been investigated. This chapter summarises the current knowledge, focussing on pesticides and emerging contaminants listed on the watch list of the European Union. However, large-scale investigations are still rare and further research will have to be conducted in this field to enable practitioners to provide recommendations for design and maintenance of treatment facilities in the field of ecotechnologies.

  • 8.
    Blecken, Godecke-Tobias
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Tondera, Katharina
    Stormwater Research Group, University of the Sunshine Coast, Maroochydore.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Metals: Occurrence, Treatment Efficiency and Accumulation Under Varying Flows2018In: Ecotechnologies for the Treatment of Variable Stormwater and Wastewater Flows / [ed] Katharina Tondera, Godecke-Tobias Blecken, Florent Chazarenc, Chris C. Tanner, Cham: Springer, 2018, p. 75-91Chapter in book (Refereed)
    Abstract [en]

    Metals were the first priority pollutants to be widely investigated in stormwater. In solid phase, they are often attached to very fine particles. The dissolved fraction creates considerable environmental problems as it is the most bioavailable fraction. Hence, removal of both fine and dissolved particles plays a major role in the treatment of polluted runoff. Ecotechnologies specifically designed to remove metals should be able to address different treatment mechanisms. However, the exhaustion of sorption capacity reduces the lifespan of treatment facilities. Additionally, metal concentrations fluctuate extremely—spatially, seasonally and over time—which poses another challenge for further increasing removal efficiencies. While soil- or sand-based systems should be designed in a way that the filter material can be exchanged, newer developments such as Floating Treatment Wetlands show promising removal capacities as the installations bind metals in sludge sediments, which can be removed from time to time. The different treatment mechanisms, aforementioned developments and techniques as well as their removal capacities will be discussed in this chapter

  • 9.
    Borris, Matthias
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Marsalek, Jiri
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    An exploratory study of the effects of stormwater pipeline materials on transported stormwater quality2017In: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732, Vol. 76, no 2, p. 247-255Article in journal (Refereed)
    Abstract [en]

    Implications of three sewer pipe materials (concrete, galvanized corrugated steel, and polyvinyl chloride (PVC)) for stormwater quality were explored in laboratory experiments, in which three types of stormwater, SW1-SW3, were circulated in 0.5 m long sewer pipe sections. SW1 and SW2 represented synthetic rainwater, without and with fine street sediment added (CTSS = 150 mg/L), respectively, and SW3 was actual stormwater with the same sediment addition as SW2. Following 20-min runs, with an equivalent distance of 500 m travelled by water particles, a number of statistically significant changes in the stormwater chemistry were observed: (i) pH of all the simulated stormwaters increased in the concrete pipe (from 7.0-7.3 to 8.1-9.3), (ii) turbidity decreased in two stormwaters with sediments (SW2 and SW3) in concrete and galvanized corrugated steel pipes (by 50 and 85%, respectively), (iii) the type of stormwater affected the observed copper (Cu) concentrations, with Cudiss concentrations as high as 25.3 μg/L noted in SW3 passing through the PVC pipe, and (iv) zinc (Zn) concentrations sharply increased (Zntot = 759-1,406 μg/L, Zndiss = 670-1,400 μg/L) due to Zn elution from the galvanized steel pipe by all three stormwaters. Such levels exceeded the applicable environmental guidelines.

  • 10.
    Galfi, Helen
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Marsalek, Jiri
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Mineral and Anthropogenic Indicator Inorganics in Urban Stormwater and Snowmelt Runoff: Sources and Mobility Patterns2017In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 228, no 7, article id 263Article in journal (Refereed)
    Abstract [en]

    Inorganic chemicals in urban stormwater and snowmelt runoff originate from catchment geology and anthropogenic activities. The occurrence, partitioning and mobility of six minerals and six trace metal (TM) indicators of anthropogenic activities were studied in stormwater, snowmelt and baseflow in four urban catchments, and the sampling of inorganics was supplemented by measurements of electrical conductivity (EC), pH and total suspended solids (TSSs). Minerals occurred at concentrations several orders of magnitude higher (1–102 mg/L) than those of TMs (10−2–102 μg/L) and reflected the composition of local groundwater seeping into sewers. Concentrations of Ca, K, Mg and Na were enhanced by baseflow contributions and followed closely the electrical conductivity. Al and Fe minerals occurred in insoluble forms, and their pollutographs were similar to those of TMs, whose concentrations mimicked, to some extent, the flux of TSS. The TMs with the highest and lowest particulate fractions were Cr&Pb and Cu&Zn, respectively. The concentrations of total TMs in snowmelt were two to four times higher than those in stormwater, and both sources likely exceeded some of the stormwater effluent limits (for Cd, Cu and Zn) proposed in Sweden. Where such concentrations depended on water hardness, the risk of toxicity might be reduced by elevated hardness of the monitored snowmelt and stormwater. Recognizing the good ecological status of the study area receiving water, Lake Storsjön, some protection against polluted runoff and snowmelt may be needed and could be achieved by implementing stormwater management measures controlling TSS and TMs.

  • 11.
    Lindfors, Sarah
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Truly dissolved and labile Cu and Zn in urban runoff from a parking lot, an industrial area and copper and zinc roofs2017In: 14th IWA/IAHR International Conference on Urban Drainage: Conference Proceedings, 2017, Prague, 2017,, 2017Conference paper (Refereed)
    Abstract [en]

    In this work two approaches were used in order to characterise the chemical speciation of Cu and Zn in urban runoff: ultrafiltration and passive sampling using diffusive gradients in thin films (DGT). Grab samples were taken from two catchments during snowmelt and from copper and zinc roofs during a snow-mixed-with-rain event. The results indicated that the catchment runoff composed of high amountsof particulate Cu and Zn, and that the dissolved Cu and Zn comprised of a variety of mobile and labile species. Whereas, the total Cu and Zn concentrations in roof runoff, to a great extent, composed of free ions

  • 12.
    Borris, Matthias
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Marsalek, Jiri
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Contribution of coarse particles from road surfaces to dissolved and particle-bound heavy metal loads in runoff: A laboratory leaching study with synthetic stormwater2016In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 573, p. 212-221Article in journal (Refereed)
    Abstract [en]

    Laboratory leaching experiments were performed to study the potential of coarse street sediments (i.e. > 250 μm) to release dissolved and particulate-bound heavy metals (i.e. Cd, Cr, Cu, Ni, Pb and Zn) during rainfall/runoff. Towards this end, street sediments were sampled by vacuuming at seven sites in five Swedish cities and the collected sediments were characterized with respect to their physical and chemical properties. In the laboratory, the sediments were combined with synthetic rainwater and subject to agitation by a shaker mimicking particle motion during transport by runoff from street surfaces. As a result of such action, coarse street sediments were found to release significant amounts of heavy metals, which were predominantly (up to 99%) in the particulate bound phase. Thus, in dry weather, coarse street sediments functioned as collectors of fine particles with attached heavy metals, but in wet weather, metal burdens were released by rainfall/runoff processes. The magnitude of such releases depended on the site characteristics (i.e. street cleaning and traffic intensity), particle properties (i.e. organic matter content), and runoff characteristics (pH, and the duration of, and energy input into, sediment/water agitation). The study findings suggest that street cleaning, which preferentially removes coarser sediments, may produce additional environmental benefits by also removing fine contaminated particles attached to coarser materials

  • 13.
    Galfi, Helen
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Marsalek, Jiri
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Indicator bacteria and associated water quality constituents in stormwater and snowmelt from four urban catchments2016In: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707, Vol. 539, p. 125-140Article in journal (Refereed)
    Abstract [en]

    SummaryFour indicator bacteria were measured in association with physico-chemical constituents and selected inorganics during rainfall, baseflow and snowmelt periods in storm sewers of four urban catchments in a northern Swedish city. The variation patterns of coliforms, E. coli, enterococci and C. perfringens concentrations were assessed in manually collected grab samples together with those of phosphorus, nitrogen, solids, and readings of pH, turbidity, water conductivity, temperature and flow rates to examine whether these constituents with variation patterns similar to those of indicator bacteria, and to exclude the constituents with less similarity. In the reduced data set, the similarities were quantified by the clustering correlation analysis. Finally, the positive/negative relationships found between indicator bacteria and the identified associated constituent groups were described by multilinear regressions. In the order of decreasing concentrations, coliforms, E. coli and enterococci were found in the highest mean concentrations during both rainfall and snowmelt generated runoff. Compared to dry weather baseflow, concentrations of these three indicators in stormwater were 10 (snowmelt runoff) to 102 (rain runoff) times higher. C. perfringens mean concentrations were practically constant regardless of the season and catchment. The type and number of variables associated with bacteria depended on the degree of catchment development and the inherent complexity of bacteria sources. The list of variables associated with bacteria included the flow rate, solids with associated inorganics (Fe and Al) and phosphorus, indicating similar sources of constituents regardless of the season. On the other hand, bacteria were associated with water temperature only during rain periods, and somewhat important associations of bacteria with nitrogen and pH were found during the periods of snowmelt. Most of the associated constituents were positively correlated with bacteria responses, but conductivity, with two associated inorganics (Si and Sr), was mostly negatively correlated in all the catchments. Although the study findings do not indicate any distinct surrogates to indicator bacteria, the inclusion of the above identified constituents (flow rate, solids and total phosphorus for all seasons, water temperature for rainfall runoff, and total nitrogen and pH for snowmelt only) in sanitary surveys of northern climate urban catchments would provide additional insight into indicator bacteria sources and their modelling.

  • 14.
    Mattsson, Jonathan
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Mattsson, Ann E.
    Gryaab AB, Utveckling, Kvalitet och miljö, Göteborg.
    Davidsson, Fredrik
    Gryaab AB, Utveckling, Kvalitet och miljö, Göteborg.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Normalization of Wastewater Quality to Estimate Infiltration/Inflow and Mass Flows of Metals2016In: Journal of environmental engineering, ISSN 0733-9372, E-ISSN 1943-7870, Vol. 142, no 11, article id 4016050Article in journal (Refereed)
    Abstract [en]

    The quality of wastewater varies between catchments due to variation in urbanisation, sewer system properties, and pollution levels. This study was conducted to identify wastewater quality parameters that could be normalized to estimate levels of infiltration/inflow (I/I) in selected catchments and to investigate the geographic origins of metals entering sewer systems. Two sampling campaigns were conducted in the five catchments of the Gothenburg area focusing on 14 water quality parameters. Data from a reference study on domestic wastewater quality to normalize the mass flows associated with pure domestic wastewater was applied. The level of dilution due to I/I in wastewater entering Rya Wastewater Treatment Plant, estimated using Tot-N and Tot-P as indicators, provided the closest fit among the water quality parameters with results obtained by established methods for the two campaigns. The results from the study also indicated which catchments generated nondomestic wastewater with higher mass flows of specified metals.

  • 15.
    Andersson-Wikström, Alexandra
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Size fractionation of dissolved metals in stormwater in Umeå, Sweden2016Conference paper (Refereed)
    Abstract [en]

    Dissolved metals are generally considered the most mobile, toxic and bioavailable form of metals. However, the partition between dissolved and particulate phases is conventionally defined by the fraction passing through a 0.45 μm membrane, even though it is widely known that this fraction also includes different types of organic and inorganic colloids. Further size fractionation of metals in the dissolved phase can be performed using different techniques. The knowledge on the metal fractionation in stormwater is useful for assessments of the metals’ bioavailability as well as the performance of stormwater treatment systems. In this study, the size fractionation of dissolved metals in stormwater from four different urban areas in the city of Umeå, Sweden, is determined using ultrafiltration. The objective is to find a pattern for the size fractionation of different metals in the dissolved phase in stormwater and, by this, estimate the bioavailability of the metals. The investigated catchment areas include a parking space, a highway and two different commercial sites. The sampling campaigns will take place in the spring of 2016, taking samples from the stormwater drainage system using automatic samplers.

  • 16.
    Borris, Matthias
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Leonhardt, Günther
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Marsalek, Jiri
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Source-Based Modeling Of Urban Stormwater Quality Response to the Selected Scenarios Combining Future Changes in Climate and Socio-Economic Factors2016In: Environmental Management, ISSN 0364-152X, E-ISSN 1432-1009, Vol. 58, no 2, p. 223-237Article in journal (Refereed)
    Abstract [en]

    The assessment of future trends in urban stormwater quality should be most helpful for ensuring the effectiveness of the existing stormwater quality infrastructure in the future and mitigating the associated impacts on receiving waters. Combined effects of expected changes in climate and socio-economic factors on stormwater quality were examined in two urban test catchments by applying a source-based computer model (WinSLAMM) for TSS and three heavy metals (copper, lead, and zinc) for various future scenarios. Generally, both catchments showed similar responses to the future scenarios and pollutant loads were generally more sensitive to changes in socio-economic factors (i.e., increasing traffic intensities, growth and intensification of the individual land-uses) than in the climate. Specifically, for the selected Intermediate socio-economic scenario and two climate change scenarios (RSP = 2.6 and 8.5), the TSS loads from both catchments increased by about 10 % on average, but when applying the Intermediate climate change scenario (RCP = 4.5) for two SSPs, the Sustainability and Security scenarios (SSP1 and SSP3), the TSS loads increased on average by 70 %. Furthermore, it was observed that well-designed and maintained stormwater treatment facilities targeting local pollution hotspots exhibited the potential to significantly improve stormwater quality, however, at potentially high costs. In fact, it was possible to reduce pollutant loads from both catchments under the future Sustainability scenario (on average, e.g., TSS were reduced by 20 %), compared to the current conditions. The methodology developed in this study was found useful for planning climate change adaptation strategies in the context of local conditions.

  • 17.
    Borris, Matthias
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Leonhardt, Günther
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Marsalek, Jiri
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Source-based modeling of stormwater quality response to projected future changes in climatic and socio-economic factors2015In: Urban Drainage Modelling 2015: Poster presentations : Proceedings of the 10th International Conference of Urban Drainage Modelling, Mont-Sainte-Anne, Québec, Canada 20-23 Swptember 2015 / [ed] Thomas Maere; Sovanna Tik; Sophie Duchense; Peter A. Vanrolleghem, 2015, p. 73-78Conference paper (Other academic)
  • 18.
    Andersson-Wikström, Alexandra
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    The release of pollutants from roofing materials in laboratory experiments2015Conference paper (Refereed)
    Abstract [en]

    Diffuse pollution sources have been recognised by the European Water Framework Directive to significantly contribute to pollution of stormwater receivers. Stormwater runoff is considered to represent diffuse pollution sources. The aim of this study was to clarify the contributions of specific sources in the urban environment to the content of organic and inorganic pollutants in stormwater. This was done by conducting laboratory screening tests of several conventional roofing materials and coatings to determine which pollutants they release and how they might contribute to the deterioration of stormwater quality. The studied pollutants include metals (Cd, Cr, Cu, Ni, Pb, V, Zn) as well as polycyclic aromatic hydrocarbons (PAHs), phthalates, pesticides, nonylphenols and –ethoxylates. Many of the studied roofing materials, e.g. roofing shingle, a PVC sheet and a bitumen paste for felt roof maintenance, exhibited the potential to release several of these substances into stormwater runoff. However, phthalates were not released from any of the studied materials under the tested conditions. In addition, quite similar materials exhibited rather different substance release profiles.

  • 19.
    Nordqvist, Kerstin
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Galfi, Helen
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Marsalek, Jiri
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Westerlund, Camilla
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Measuring solid concentrations in urban stormwater and snowmelt: a new operational procedure2014In: Environmental Science: Processes & Impacts, ISSN 2050-7887, E-ISSN 2050-7895, Vol. 16, no 9, p. 2172-2183Article in journal (Refereed)
    Abstract [en]

    A comparative study of five methods measuring suspended sediment or solid concentrations in water–sediment mixtures indicated that, depending on the method used, broadly varying results can be obtained. For water–sediment mixtures containing sand size particles, the standard TSS method produced negatively biased results, accounting for 0 to 90% of the present solids; the negative bias directly depended on the magnitude of the sand fraction in the water–sediment mixture. The main reason for the differences between the TSS and the rest of the methods laid in the handling of samples; in the former methods, whole samples were analysed, whereas the TSS analysis was performed on sub-samples withdrawn from the water sample, the withdrawal process tending to exclude large particles. The methods using whole water–solid samples, rather than aliquots withdrawn from such samples, produced accurate estimates of solid concentrations, with a fairly good precision. Two whole-sample methods were studied in detail, a slightly modified standard SSC-B method and the newly proposed operational procedure referred to as the Multiple Filter Procedure (MFP), using three filters arranged in a series with decreasing pore sizes (25, 1.6 and 0.45 µm). Both methods assessed accurately concentrations of solids in a broad range of concentrations (200–8000 mg L−1) and particle sizes (0.063–4.0 mm). The newly introduced MFP was in good agreement with the SSC procedure, the differences between the two procedures not exceeding the standard bias defined for the SSC-B method. The precision of both SSC and MFP was generally better than ±10%. Consequently, these methods should be used when the total mass of transported solids is of interest.

  • 20.
    Österlund, Helene
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Faarinen, Mikko
    Ingri, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Baxter, Douglas
    Contribution of organic arsenic species to total arsenic measurements using ferrihydrite-backed diffusive gradients in thin films (DGT)2012In: Environmental Chemistry, ISSN 1448-2517, E-ISSN 1449-8979, Vol. 9, no 1, p. 55-62Article in journal (Refereed)
    Abstract [en]

    In previous publications discussing arsenic determination using ferrihydrite-backed diffusive gradients in thin films (DGT) devices, organic arsenic forms have been disregarded, even though it is known that the two most prevalent in natural waters, dimethylarsinate (DMA) and monomethylarsonate (MMA), may adsorb to ferrihydrite and thereby be included in the measurement. In this work the accumulation of DMA and MMA, as well as inorganic arsenite and arsenate, to ferrihydrite-backed DGT devices was investigated. It could be demonstrated that MMA, and under acidic conditions also DMA, adsorbed to the binding layer and might therefore contribute to the total mass of measured arsenic. Diffusion coefficients were measured for all four species to enable quantification of DGT-labile concentrations of organic and inorganic arsenic. Elution of the analytes from the ferrihydrite binding layer was performed using 1 mL of 1 M NaOH to facilitate arsenic speciation analysis using chromatographic separation. Average recovery rates were between 87 and 108%. This study shows that the contribution of DMA and MMA to the total accumulated mass must be taken into consideration when evaluating DGT data in future studies.

  • 21.
    Österlund, Helene
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Gelting, Johan
    Nordblad, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Baxter, Douglas
    ALS Scandinavia AB.
    Ingri, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Copper and nickel in ultrafiltered brackish water: labile or non-labile?2012In: Marine Chemistry, ISSN 0304-4203, E-ISSN 1872-7581, Vol. 132-133, no 1, p. 34-43Article in journal (Refereed)
    Abstract [en]

    Copper and nickel were sampled at three stations in the Baltic Sea using diffusive gradients in thin films (DGT) passive samplers and ultrafiltration (< 1 kDa). Two versions of DGT devices were used, the normal open pore (OP) and a restricted pore (RP). The OP DGT and RP DGT concentrations closely followed each other both in depth profiles and time series. The lack of significant difference between OP and RP DGT suggests that the labile complexes were smaller than the pore size of the RP gel (approximately 1 nm). These data, together with OP DGT measurements at the same location in two different years, clearly demonstrate that the DGT method is robust and indicates reproducible results during routine field conditions.Between 50 and 80% of the ultrafiltered fractions for Ni and Cu could not be detected by the DGT method, using standard procedures. This suggests the presence of complexing ligands for Cu and Ni. Assuming 100% complexation of Ni to fulvic acid ligand gave DGT concentrations similar to ultrafiltered Ni concentrations. The equivalent calculation for Cu indicates that up to 75% of the ultrafiltered Cu fraction is non-labile. The non-labile Cu complexes are proposed to be produced at sea since the fraction increases with decreasing terrestrial influence.

  • 22.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Forsberg, Jerry
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ingri, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ecke, Frauke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Alakangas, Lena
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Fractionation of trace metals in a contaminated freshwater stream using membrane filtration, ultrafiltration, DGT and transplanted aquatic moss2012In: Geochemistry: Exploration, Environment, Analysis, ISSN 1467-7873, E-ISSN 2041-4943, Vol. 12, no 4, p. 303-312Article in journal (Refereed)
    Abstract [en]

    Four metal speciation and fractionation techniques – DGT (diffusive gradients in thin films), 1-kDa ultrafiltration, 0.22-µm membrane filtration and aquatic moss – were simultaneously applied to a small, contaminated freshwater stream in northern Sweden to investigate differences and similarities between the methods regarding trace metal speciation and their dependence on geochemical water properties. The investigated metals comprise Al, Cd, Co, Cu, Fe, Mn, Ni, and Zn. The normal DGT devices with Chelex cation exchanger were used. Shoots from the aquatic moss Fontinalis antipyretica L ex Hedw. were collected in a non-polluted brook and transplanted to the sampling site for exposure. It was evident that 0.22-µm membrane filtration, 1-kDa ultrafiltration and DGT generally measured different metal fractions where

  • 23.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Further characterisation and applications of the diffusive gradients in thin films technique: In situ measurements of anions and cations in environmental waters2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    As both the toxicity and the mobility of trace elements are related to chemical forms present, robust methods for element speciation analysis are of great interest. During the last 15 years, hundreds of scientific articles have been published on the development and applications of the diffusive gradients in thin films (DGT) passive sampling technique. The aim of this thesis was to explore new application areas as well as carry out further characterisation of DGT-adsorbents already on the market. The commercially available DGT containing ferrihydrite adsorbent, currently in use for the determination of phosphate and inorganic arsenic, was characterised with respect to anionic arsenate, molybdate, antimonate, vanadate and tungstate determination. Tests were performed in the laboratory as well as in the field. Diffusion coefficients were determined for the anions using two different methods with good agreement. Simultaneous measurements of arsenate were conducted as quality control to facilitate comparison of the performance with previous work. The ferrihydrite-backed DGT was concluded useful for application over the pH-range 4 to 10 for vanadate and tungstate, and 4 to <8 for molybdate and antimonate. At pH values ≥8, deteriorating adsorption was observed. Further investigations of the ferrihydrite-DGT device were done with respect to organic arsenic species. From previous research it is understood that the two most prevalent forms of organic arsenic in natural waters, monomethylarsinate (MMA) and dimethylarsonate (DMA), adsorb to ferrihydrite. It was concluded that MMA and under some conditions DMA are accumulated and might therefore be included in total arsenic measurements. A method for speciation of inorganic As, DMA and MMA was described. DGT sampling was applied at three stations, with different salinities, in the brackish Baltic Sea. Time series as well as vertical profiles were taken and complementary membrane- (<0.22 μm) and ultrafiltrations (<1 kDa) were conducted on discrete samples collected at 5 m depth. A combination of a restricted pore (RP) version of DGT and the normal open pore (OP) DGT, both loaded with Chelex cation exchanger, was used for speciation of copper and nickel. Due to minimal differences in results between the OP- and RP-DGTs it was suggested that the complexes were smaller than the pore size of the RP gel (~1 nm) resulting in both DGTs accumulating essentially the same fraction. Furthermore, there seemed to be a trend in copper speciation indicating a higher degree of strong complexation with increasing salinity. The low salinity stations are more impacted by fluvial inputs which will likely affect the nature and composition of the organic ligands present. Assuming that copper forms more stable complexes with ligands of marine rather than terrestrial origin would be sufficient to explain the observed trend. Additionally, uranium results from the same sampling tours were used to evaluate OP-DGT for in situ uranium measurements. Previous research has focused on laboratory studies for characterisation of a range of suitable uranium adsorbents, including Chelex. From the Baltic Sea study, a strong correlation between DGT-labile uranium and pH was revealed. The correlation could not be associated to organic complexation, since the ultrafiltration results implicated that uranium was truly dissolved. Instead it must be attributed to the formation of stable inorganic anionic uranyl-carbonate complexes, the stability of which increases with increasing numbers of carbonates and pH. Transplanted aquatic moss has commonly been used to monitor bioavailable trace metal contaminations in freshwater. Like the DGT technique the method has the advantage of generating time-weighted averaged concentrations. The DGT technique has in several previous studies been suggested to mimic biological uptake of trace metals. Four speciation/fractionation techniques – DGT, transplanted aquatic moss, ultrafiltration (1 kDa) and membrane filtration (0.22 μm) – were used in parallel for measurements of Al, Cd, Co, Cu, Fe, Mn, Ni and Zn in a contaminated freshwater stream in northern Sweden. Differences and similarities between the methods were investigated and how these depend on geochemical water quality. Strong correlations between DGT-results and the concentrations in the filtrate (<0.22 μm) and ultrafiltration permeate for Al, Cu, Cd, Co and Zn were detected and, generally, elevated trace metal concentrations were found in the transplanted moss, compared to moss from the non-polluted reference stream. However, no correlation between moss and DGT-labile concentrations could be discerned.

  • 24. Baxter, Douglas
    et al.
    Faarinen, Mikko
    ALS Scandinavia AB.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Rodushkin, Ilya
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Christensen, Morten
    ALS Scandinavia AB, Täby.
    Serum/plasma methylmercury determination by isotope dilution gas chromatography: inductively coupled plasma mass spectrometry2011In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 701, no 2, p. 134-138Article in journal (Refereed)
    Abstract [en]

    A method for the determination of methylmercury in plasma and serum samples was developed. The method uses isotope dilution with 198Hg-labelled methylmercury, extraction into dichloromethane, back-extraction into water, aqueous-phase ethylation, purge and trap collection, thermal desorption, separation by gas chromatography, and mercury isotope specific detection by inductively coupled plasma mass spectrometry. By spiking 2 mL sample with 1.2 ng tracer, measurements in a concentration interval of (0.007–2.9) μg L−1 could be performed with uncertainty amplification factors <2. A limit of quantification of 0.03 μg L−1 was estimated at 10 times the standard deviation of concentrations measured in preparation blanks. Within- and between-run relative standard deviations were <10% at added concentration levels of 0.14 μg L−1, 0.35 μg L−1 and 2.8 μg L−1, with recoveries in the range 82% to 110%. Application of the method to 50 plasma/serum samples yielded a median (mean; range) concentration of methylmercury of 0.081 (0.091; <0.03–0.19) μg L−1. This is the first time methylmercury has been directly measured in this kind of specimen, and is therefore the first estimate of a reference range.

  • 25.
    Öhlander, Björn
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Forsberg, Jerry
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ingri, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ecke, Frauke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Alakangas, Lena
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Speciation of trace metals in a contaminated stream at the Laver mine by using membrane filtration, ultrafiltration, DGT and transplanted aquatic moss2011Conference paper (Refereed)
  • 26.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Applications of the DGT technique for measurements of anions and cations in natural waters2010Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Since the toxicity and mobility of trace metals are related to the metals' speciation, robust methods for trace metal speciation analysis are of great interest. During the last 15 years, hundreds of scientific articles have been published on the development and applications of the diffusive gradients in thin films (DGT) passive sampling technique.In this work the commercially available DGT containing ferrihydrite adsorbent, used for determination of phosphate and inorganic arsenic, was characterised with respect to anionic molybdate, antimonate, vanadate and tungstate determination. Tests were performed in the laboratory as well as in the field. Diffusion coefficients were determined for the anions using two different methods with good agreement. Simultaneous measurements of arsenate were conducted as quality control to facilitate comparison of the performance with previous work. The ferrihydrite-backed DGT was concluded useful for application over the pH-range 4 to 10 for vanadate and tungstate, and 4 to <8 for molybdate and antimonate. At pH values ≥8, deteriorating adsorption was observed.The combination of a restricted pore (RP) version of DGT and the normal open pore (OP) DGT was used for speciation of copper and nickel at three brackish water stations with different salinities in the Baltic Sea. Time series and depth profiles were taken, and complementary membrane- (<0.22 μm) and ultrafiltration (<1 kDa) was conducted. Comparing DGT and ultrafiltration measurements indicated that copper and nickel were complexed. Due to small differences in results between the OP and RP DGTs it was suggested that the complexes were smaller than the pore size of the RP gel (~1 nm) resulting in that both DGTs accumulating essentially the same fraction. Further, there seemed to be a trend in copper speciation indicating higher degree of strong complexation with increasing salinity. The low salinity stations are more affected by fluvial inputs which will likely affect the nature and composition of the organic ligands present. Assuming that copper forms more stable complexes with ligands of marine rather than terrestrial origin would be sufficient to explain the observed trend.

  • 27. Österlund, Helene
    et al.
    Chlot, Sara
    Faarinen, Mikko
    ALS Laboratory Group, Luleå.
    Widerlund, Anders
    Rodushkin, Ilya
    Ingri, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Baxter, Douglas
    Simultaneous measurements of As, Mo, Sb, V and W using a ferrihydrite diffusive gradients in thin films (DGT) device2010In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 682, no 1-2, p. 59-65Article in journal (Refereed)
    Abstract [en]

    The ferrihydrite-backed DGT (diffusive gradients in thin films), recently developed for arsenic and phosphate measurements was, for the first time, characterized with respect to molybdate, antimonate, vanadate and tungstate determination. Arsenate was included in the characterization to allow comparison with literature data and thus provide quality control of the measurements. In addition to laboratory experiments, field measurements were carried out in a natural stream in northern Sweden affected by mine drainage. It was shown that ferrihydrite-DGT is suitable for simultaneous determination of labile arsenic, molybdate, antimonate, vanadate and tungstate over a wide pH range. Diffusion coefficients were estimated using two different methods; diffusion cell and direct uptake to DGT devices in synthetic solutions. Estimations of the coefficients using the direct uptake method were performed between pH 4 and 8. The results from the two methods agreed well irrespective of pH, except for molybdate and antimonate that showed decreased values at pH 8. Adsorption of the analytes to ferrihydrite gel discs was rapid at all pH values. However, there was a tendency toward lower adsorption affinity for antimonate compared to the other anions. 100% recovery of accumulated analytes was achieved through complete dissolution of the ferrihydrite adsorbent using 1.4 mol L-1 HNO3 with 0.1 mol L-1 HF. From field sampling it was concluded that the opportunities for accurate antimonate and molybdate determination decrease at pH ≥8.7. DGT labile concentrations were generally lower than dissolved concentrations. Relatively lower DGT concentrations, compared to dissolved (<0.45 μm), were observed under a period when ferric oxide precipitations were detected on the DGT protective filter.

  • 28.
    Engström, Emma
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Rodushkin, Ilya
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ingri, Johan
    Baxter, Douglas
    Ecke, Frauke
    Österlund, Helene
    Öhlander, Björn
    Temporal isotopic variations of dissolved silicon in a pristine boreal river2010In: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 271, no 3-4, p. 142-152Article in journal (Refereed)
    Abstract [en]

    It has previously been concluded that the stable Si isotopes are fractionated during geochemical and biogeochemical elemental transfers, such as weathering and precipitation of clays and biogenic Si, which has opened up the possibility of using Si as a tracer in natural terrestrial ecosystems. Furthermore, quantification of the biogenic impact on the biogeochemical Si cycle has attracted significant scientific interest since biological control has been suggested. Previous observations of seasonal variations in the dissolved Si isotopic pattern further imply that high-frequency riverine sampling during main hydrological events might provide important information about natural processes governing the fluvial biogeochemical Si cycle.Therefore, temporal variations in the isotopic composition of riverine dissolved Si were investigated for the Kalix River, Northern Sweden, the largest pristine river system in Europe, based on high-frequency sampling during a period of 25 weeks from early April to early October 2006. Temporal variations spanning 0.4‰ for δ29Si and 0.8‰ for δ30Si of dissolved Si in the Kalix River were observed during the period, suggesting that the riverine dissolved Si input to the oceans cannot be considered to have a constant Si isotopic composition even on a short time scale.The results implicate biogeochemical Si-cycling via formation and dissolution of biogenic silica as processes significantly affecting the dissolved Si transport in boreal systems during April to early October. The Si budget in the river system appeared to be controlled by relative Si enrichment during high discharge events and relative Si depletions in the subarctic mountainous and lake dominated areas. The Si enrichments and depletions were accompanied by decreasing and increasing riverine δ29Si and δ30Si, respectively. These isotope variations can be explained by release of plant derived silica, depleted in heavier Si isotopes, during the spring snowmelt. Further, increased volumetric contribution from the headwater and losses of dissolved Si due to biogenic silica formation by diatoms in the subarctic lakes at a later period are expected to be responsible for the preferential losses of lighter isotopes, as further verified by land cover analysis

  • 29.
    Österlund, Helene
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Rodushkin, Ilya
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ylinenjärvi, Karin
    ALS Scandinavia AB.
    Baxter, Douglas
    Determination of total chlorine and bromine in solid wastes by sintering and inductively coupled plasma-sector field mass spectrometry2009In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 29, no 4, p. 1258-1264Article in journal (Refereed)
    Abstract [en]

    A sample preparation method based on sintering, followed by analysis by inductively coupled plasma-sector field mass spectrometry (ICP-SFMS) for the simultaneous determination of chloride and bromide in diverse and mixed solid wastes, has been evaluated. Samples and reference materials of known composition were mixed with a sintering agent containing Na2CO3 and ZnO and placed in an oven at 560 °C for 1 h. After cooling, the residues were leached with water prior to a cation-exchange assisted clean-up. Alternatively, a simple microwave-assisted digestion using only nitric acid was applied for comparison. Thereafter the samples were prepared for quantitative analysis by ICP-SFMS. The sintering method was evaluated by analysis of certified reference materials (CRMs) and by comparison with US EPA Method 5050 and ion chromatography with good agreement. Median RSDs for the sintering method were determined to 10% for both chlorine and bromine, and median recovery to 96% and 97%, respectively. Limits of detection (LODs) were 200 mg/kg for chlorine and 20 mg/kg for bromine. It was concluded that the sintering method is suitable for chlorine and bromine determination in several matrices like sewage sludge, plastics, and edible waste, as well as for waste mixtures. The sintering method was also applied for determination of other elements present in anionic forms, such as sulfur, arsenic, selenium and iodine.

  • 30. Engström, Emma
    et al.
    Rodushkin, Ilya
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ingri, Johan
    Baxter, Douglas
    Ecke, Frauke
    Österlund, Helene
    Öhlander, Björn
    Temporal isotopic variations of dissolved silicon in a pristine boreal river2009In: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 73, no 13, Suppl. S, p. A333-Article in journal (Other academic)
    Abstract [en]

    Interest in quantifying the biogenic impact on the terrestrial biogeochemical Si cycle has increased significantly since biological control has been suggested. Previous observations of isotopic fractionation of Si during biogeochemical and geochemical processes imply that seasonal dissolved Si isotopic patterns in rivers have the potential for use in extracting information about the riverineand terrestrial biogeochemical Si cycles.Therefore, variations in the isotopic composition of dissolved riverine Si were investigated for the Kalix River, Northern Sweden, one of the largest pristine rivers in Europe, based on high-frequency sampling during a period of 25 weeks from early April to early October 2006. Temporal variations spanning 0.4. for δ29Si and 0.8. for δ30Si of dissolved Si in the Kalix River were observed during the period, suggesting that the riverine Si input to the oceans cannot be considered to have a constant Si isotopic composition even on a short time scale. The results implicate biogeochemical Si-cycling via formation and dissolution of biogenic silica as major processes controlling the Si transport in boreal systems. The Si budget in the river system appeared to be controlled by relative Si accretions during high discharge events and relative Si depletions in the subarctic mountainous and lake dominated areas. There were also temporal variations in Si isotopic composition with accretion (relative Si contribution), accompanied by depletion of the heavier Si isotopes, while the opposite trend was observed during periods of riverine Si depletion. These isotope variations can be explained by release of plant derived silica, depleted in heavier Si isotopes, during the spring snowmelt. Further, increased volumetric contribution from the headwater and losses of Si due to biogenic silica formation by diatoms in the subarctic lakes at a later period are expected to be responsible for the preferential losses of lighter isotopes. These conclusions are further verified by land cover analysis.

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