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  • 1. Borga, Katrine
    et al.
    Fjeld, Eirik
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, Michael S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Consistency in Trophic Magnification Factors of Cyclic Methyl Siloxanes in Pelagic Freshwater Food Webs Leading to Brown Trout2013Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 47, nr 24, s. 14394-14402Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cyclic volatile methyl siloxanes (cVMS) concentrations were analyzed in the pelagic food web of two Norwegian lakes (Mjosa, Randsfjorden), and in brown trout (Salmo trutta) and Arctic char (Salvelinus alpinus) collected in a reference lake (Femunden), in 2012. Lakes receiving discharge from wastewater treatment plants (Mjosa and Randsfjorden) had cVMS concentrations in trout that were up to 2 orders of magnitude higher than those in Femunden, where most samples were close to the limit of quantification (LOO). Food web biomagnification of cVMS in Mjosa and Randsfjorden was quantified by estimation of trophic magnification factors (TMFs). TMF for legacy persistent organic pollutants (POPs) were analyzed for comparison. Both decamethylcyclopentasiloxane (DS) and dodecamethylcyclohexasiloxane (D6) biomagnified with TMFs of 2.9 (2.1-4.0) and 2.3 (1.8-3.0), respectively. Octamethylcyclotetrasiloxane (D4) was below the LOQ in the majority of samples and had substantially lower biomagnification than for D5 and D6. The cVMS TMFs did not differ between the lakes, whereas the legacy POP TMFs were higher in Mjosa than inRandsfjorden. Whitefish had lower cVMS bioaccumulation compared to legacy POPs, and affected the TMF significance for cVMS, but not for POPs. TMFs of D5 and legacy contaminants in Lake Mjosa were consistent with those previously measured in Mjosa.

  • 2. Borga, Katrine
    et al.
    Fjeld, Eirik
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, Michael S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Food Web Accumulation of Cyclic Siloxanes in Lake Mjosa, Norway2012Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 46, nr 11, s. 6347-6354Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The biomagnification of the cyclic volatile methyl siloxanes octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexatetrasiloxane (D6) was analyzed in the Lake Mjosa food web in Norway from zooplankton and Mysis to planktivorous and piscivorous fish. The trophic magnification factor (TMF) for D5 was determined and compared with TMFs of several legacy contaminants: polychlorinated biphenyl (PCB) congeners 153 and 180, polybrominated diphenyl ether (PBDE) congeners 47 and 99, and p,p'-DDE. D5 showed TMF significantly greater than 1, implying food web biomagnification (TMF = 2.28, CI: 1.22-4.29). This contrasts with two studies that reported TMF < 1, which may reflect variability in TMF between food webs. The Lake Mjosa D5 TMF was sensitive to the species included at the higher trophic level; whole food web TMF differed from TMF excluding smelt (Osmerus eperlanus) or brown trout (Salmo trutta) (TMF-SMELT = 1.62, CI: 0.96-2.72; TMF-TROUT = 3.58, CI: 1.82-7.03). For legacy contaminants (e.g., PCB-153 and PCB-180), the TMFs were less sensitive to the food web composition, and a better model fit was obtained compared to D5. The differences in biomagnification behavior between D5 and the legacy contaminants suggest that the biomagnification of D5 is being governed by species-specific properties such as biotransformation rate or tissue distribution that differ from those of legacy contaminants.

  • 3. Buser, Andreas M.
    et al.
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Bogdal, Christian
    MacLeod, Matthew
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Scheringer, Martin
    Hungerbuehler, Konrad
    Concentrations in Ambient Air and Emissions of Cyclic Volatile Methylsiloxanes in Zurich, Switzerland2013Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 47, nr 13, s. 7045-7051Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Tens of thousands of tonnes of cyclic volatile methylsiloxanes (cVMS) are used each year globally, which leads to high and continuous cVMS emissions to air. However, field measurements of cVMS in air and empirical information about emission rates to air are still limited. Here we present measurements of decamethylcyclopentasfloxane (D-5) and dodecamethylcyclohexasiloxane (D-6) in air for Zurich, Switzerland. The measurements were performed in January and February 2011 over a period of eight days and at two sites (city center and background) with a temporal resolution of 6-12 h. Concentrations of Ds and D-6 are higher in the center of Zurich and range from 100 to 650 ng m(-3) and from 10 to 79 ng m(-3), respectively. These values are among the highest levels of D-5 and D-6 reported in the literature. In a second step, we used a multimedia environmental fate model parametrized for the region of Zurich to interpret the levels and time trends in the cVMS concentrations and to back calculate the emission rates of D-5 and D-6 from the city of Zurich. The average emission rates obtained for D-5 and D-6 are 120 kg d(-1) and 14 kg d(-1), respectively, which corresponds to per capita emissions of 310 mg capita(-1) d(-1) for D-5 and 36 mg capita(-1) d(-1) for D-6.

  • 4.
    de Wit,
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Nylund, Kerstin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Eriksson, Ulla
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Haglund, M.
    Kierkegaard,
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Asplund, Lillemor
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Brominated flame retardants in sludge from 50 Swedish sewage treatment plants: Evidence of anaerobic degradation of HBCD and TBBPA.2007Inngår i: Dioxin 2007, Tokyo, Japan: 2-7 September, 2007Konferansepaper (Annet (populærvitenskap, debatt, mm))
  • 5.
    de Wit, Cynthia A.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Nylund, Kerstin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Eriksson, Ulla
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Haglund, Malin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Asplund, Lillemor
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Brominated flame retardants in sludge from 50 Swedish sewage treatment plants: Evidence of anaerobic degradation of HBCD and TBBPA.2007Inngår i: Fourth International Worskhop on Brominated Flame Retardants BFR 2007: Amsterdam, the Netherlands, 24-27 April., 2007Konferansepaper (Annet vitenskapelig)
  • 6.
    de Wit, Cynthia A.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Nylund, Kerstin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Eriksson, Ulla
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Haglund, Malin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Asplund, Lillemor
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Brominated flame retardants in sludge from 50 Swedish sewage treatment plants: Evidence of anaerobic degradation of HBCD and TBBPA.2007Inngår i: The 27th International Symposium on Halogenated Persistent Organic Pollutants (Dioxin 2007), Tokyo, Japan, 2-7 September, 2007., 2007Konferansepaper (Annet vitenskapelig)
  • 7.
    Jahnke, Annika
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi. Helmholtz Centre for Environmental Research – UFZ, Germany.
    Holmbäck, Jan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Argelia Andersson, Rina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Mayer, Philipp
    MacLeod, Matthew
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Differences between Lipids Extracted from Five Species Are Not Sufficient To Explain Biomagnification of Nonpolar Organic Chemicals2015Inngår i: Environmental Science and Technology Letters, ISSN 2328-8930, Vol. 2, nr 7, s. 193-197Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Lipids are the major sorptive phase for many organic chemicals that bioaccumulate in foodwebs. However, lipids are usually operationally defined by the extraction protocol. Large differences in sorptive capacities between species would violate assumptions implicit in widely used lipid-normalization procedures and invalidate generic bioaccumulation factors. We extracted lipids from five species from different trophic levels and domains and determined fractions of triglycerides, phospholipids, and cholesterol. We passively dosed the lipids with cyclic volatile methylsiloxanes and chlorobenzenes via headspace from spiked olive oil to determine their sorptive capacities. Lipids from seal blubber and pork bacon solely composed of triglycerides had capacities similar to that of olive oil; lipids from mussels, herring, and guillemot egg had quantifiable fractions of phospholipids and cholesterol and showed capacities reduced by factors of up to 2.3-fold. Generally, the sorptive capacities of the lipids were not elevated relative to the olive oil controls and are unlikely to explain a substantial part of biomagnification.

  • 8.
    Kierkegaard, A
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Adolfsson-Erici, M
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, M
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    A Sensitive Method for the Analysis of Decamethylcyclopentasiloxane (D5) in Biota2008Inngår i: SETAC North America 29th Annual Meeting: 16-20 November, 2008Konferansepaper (Fagfellevurdert)
  • 9.
    Kierkegaard, A
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Adolfsson-Erici, M
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, M
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Decamethylcyclopentasiloxane (D5) Concentrations in Fish from Urban and Remote Lakes in Sweden2008Inngår i: SETAC North America 29th Annual Meeting: 16-20 November, 2008Konferansepaper (Fagfellevurdert)
  • 10.
    Kierkegaard, Amelie
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Asplund, Lillemor
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    de Wit, Cynthia
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, Michael
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Thomas, G.O.
    Sweetman, A.J.
    Jones, K.C.
    Fate of Higher Brominated PBDEs in Lactating Cows2007Inngår i: Environ. Sci. Technol., Vol. 41, s. 417-423Artikkel i tidsskrift (Fagfellevurdert)
  • 11.
    Kierkegaard, Amelie
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Bignert, Anders
    McLachlan, Michael S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Bioaccumulation of decamethylcyclopentasiloxane in perch in Swedish lakes2013Inngår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 93, nr 5, s. 789-793Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Decamethylcyclopentasiloxane (D5), a high production volume chemical used in personal care products, enters the environment both via air and sewage treatment plant (STP) recipients. It has been found in fish, and there is concern that it may be a bioaccumulative substance. In this work D5 was analyzed in perch from six Swedish lakes that did not receive STP effluent, and in perch and sediment from six lakes that received STP effluent. In the lakes receiving the STP effluent, the D5 concentrations in sediment varied over three orders of magnitude and were correlated with the number of persons connected to the STP normalized to the surface area of the receiving body. In the lakes not receiving effluent, the D5 levels in perch were all below the LOQ while D5 was above the LOQ in almost all perch from lakes that received effluent. The D5 concentrations in perch and sediment from the lakes receiving STP effluent were correlated. This shows that STP effluent is a much more important source of D5 to aquatic ecosystems than atmospheric deposition, and that the risk of adverse effects of D5 on aquatic life will be greatest in small recipients receiving large amounts of STP effluent. The bioaccumulation of D5 was compared to that of PCB 180 on the basis of multimedia bioaccumulation factors (mmBAFs), which describe the fraction of the contaminant present in the whole aquatic environment (i.e. water and surface sediment) that is transferred to the fish. In four of the six lakes the mmBAF of D5 was >0.3 of the mmBAF of PCB 180. Given that PCB 180 is a known highly bioaccumulative chemical, this indicates that the bioaccumulation of D5 in perch is considerable.

  • 12.
    Kierkegaard, Amelie
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Bignert, Anders
    McLachlan, Michael S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Cyclic volatile methylsiloxanes in fish from the Baltic Sea2013Inngår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 93, nr 5, s. 774-778Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Laboratory studies suggest that the cyclic volatile methylsiloxanes (cVMS) octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (05) and dodecamethylcyclohexasiloxane (D6) will persist in the aquatic environment and bioaccumulate in fish. Here these cVMS were measured in herring collected in the Swedish waters of the Baltic Sea and the North Sea and in grey seals from the Baltic Proper. D4, D5, and D6 were present in herring muscle at concentrations around 10, 200, and 40 ng g(-1) lipid weight, respectively. The ratio of these concentrations was similar to the relative magnitude of estimated emissions to water, suggesting that the efficiency of overall transfer through the environment and food web was similar (within a factor 2-3) for the three chemicals. The concentrations of D5 and D6 were similar in herring caught in the highly populated Baltic Proper and in the less populated Bothnian Sea and Bothnian Bay. The D4 concentrations were lower at the most remote northern station, suggesting that D4 is less persistent than D5 and D6. Herring from the North Sea had lower levels of all three chemicals. The concentrations of D4, D5 and D6 in grey seal blubber were lower than the lipid normalized concentrations in herring, indicating that they do not biomagnify in grey seals.

  • 13.
    Kierkegaard, Amelie
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    De Wit, Cynthia A
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Asplund, Lillemor
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, Michael S
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Thomas, Gareth O
    Sweetman, Andrew J
    Jones, Kevin C
    A mass balance of tri-hexabrominated diphenyl ethers in lactating cows.2009Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 43, nr 7, s. 2602-2607Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Beef and dairy products can be important vectors of human exposure to polybrominated diphenylethers (BDEs), and hence an understanding of BDE transfer from feed to cows' milk and tissue is important for BDE exposure assessment The fate of tri- to hexaBDEs in lactating cows exposed to a naturally contaminated diet was studied by analyzing feed, feces, and milk samples from a mass balance study. Tissue distribution was studied in one cowslaughtered afterthe experiment The carryover rates from feed to milk ranged from 0.15 to 0.35 for the major congeners. Lower values were observed for several of the tetrabrominated congeners, and this was attributed to metabolism. The dietary absorption efficiency decreased with increasing octanol-water partition coefficient of the BDE congener. The absorption behavior was consistent with a model based on chemical lipophilicity, but agreed less well with a model based on effective molecular diameter, and it violated Lipinski's "rule of 5". The lipid normalized concentrations were similar in all tissues analyzed including liver and milk, suggesting that tissue distribution is governed by partitioning into lipids. Overall, the behavior of the tri- to hexaBDEs was consistent with that observed for other classes of halogenated aromatic contaminants such as PCBs and PCDD/Fs, but it differed markedly from the behavior of the hepta- decaBDEs.

  • 14.
    Kierkegaard, Amelie
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, Michael S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Determination of decamethylcyclopentasiloxane in air using commercial solid phase extraction cartridges2010Inngår i: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1217, nr 21, s. 3557-3560Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Decamethylcyclopentasiloxane (D-5), a high production volume chemical used in personal care products. has been designated for regulation in Canada and is under review in the EU because of concerns about its persistence and potential for bioaccumulation in the environment. D-5 is a volatile compound expected to be found primarily in air, but there is little information on atmospheric concentrations due to the lack of sensitive analytical methods. Here a simple and sensitive method to determine D-5 in ambient air is presented. The challenge in the environmental analysis of D-5 is avoiding contamination. Our method is based on the high trapping efficiency of the sorbent [solute ENV+, combined with a comparably high sampling rate. A small amount of sorbent (10 mg) is eluted in a small volume of n-hexane (0.1-0.6 mL). which is injected onto a GC/MS system without further processing. The simplicity of the method enables the use of a field blank for every sample to trace contamination. The method provides low limits of quantification (similar to 0.3 ng/m(3)), good repeatability and limited breakthrough (similar to 1%). By lowering the limit of quantification compared to published work by almost two orders of magnitude, it became possible to quantify D5 in ambient air at locations remote from strong point sources. The concentrations at a rural Swedish site ranged from 0.7 to 8 ng/m(3) over a period of 4 months.

  • 15.
    Kierkegaard, Amelie
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, Michael S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Determination of linear and cyclic volatile methylsiloxanes in air at a regional background site in Sweden2013Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 80, s. 322-329Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A number of volatile methylsiloxanes have been identified as environmental contaminants and several are currently the subject of detailed risk assessments due to concerns that they may be persistent, bioaccumulative and toxic in the environment. Once emitted these chemicals reside primarily in the atmosphere. Consequently, knowledge of their concentrations in air is essential to understanding their fate in the environment and any potential adverse impacts. We developed a method to analyse 4 cyclic volatile methylsiloxanes (D3, D4, D5 and D6) and 4 linear volatile methylsiloxanes (L3, L4, L5 and L6) in air at regional background levels. The method showed good repeatability (median difference between sample pairs of 2-8%) and low limits of quantification (from 3.8 pg m(-3) for L3 to 320 pg m(-3) for D4). However, the analysis of D3 and D4 was confounded by the transformation of D5 to these analytes on the sampling cartridge. During a sampling campaign with a daily temporal resolution between November 4 and December 14 2011, all analytes with the exception of L5 and L6 could be quantified in all samples. It was hypothesized that the ratio of the concentrations of different VMS reflected the relative strength of their emissions to the airshed due to the slow phototransformation of the VMS at high latitudes in winter. This was supported by available emissions information.

  • 16.
    Kierkegaard, Amelie
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Sellström, Ulla
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, Michael S
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Environmental analysis of higher brominated diphenyl ethers and decabromodiphenyl ethane.2009Inngår i: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1216, nr 3, s. 364-375Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Methods for environmental analysis of higher brominated diphenyl ethers (PBDEs), in particular decabromodiphenyl ether (BDE209), and the recently discovered environmental contaminant decabromodiphenyl ethane (deBDethane) are reviewed. The extensive literature on analysis of BDE209 has identified several critical issues, including contamination of the sample, degradation of the analyte during sample preparation and GC analysis, and the selection of appropriate detection methods and surrogate standards. The limited experience with the analysis of deBDethane suggests that there are many commonalities with BDE209. The experience garnered from the analysis of BDE209 over the last 15 years will greatly facilitate progress in the analysis of deBDethane.

  • 17.
    Kierkegaard, Amelie
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    van Egmond, Roger
    McLachlan, Michael S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Cyclic Volatile Methylsiloxane Bioaccumulation in Flounder and Ragworm in the Humber Estuary2011Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 45, nr 14, s. 5936-5942Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cyclic volatile methylsiloxanes are being subjected to regulatory scrutiny as possible PET chemicals. The investigation of bioaccumulation has yielded apparently contradictory results, with high laboratory fish bioconcentration factors on the one hand and low field trophic magnification factors on the other. In this study, octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) were studied along with polychlorinated biphenyls (PCBs) in sediments, ragworm, and flounder from six sites in the Humber Estuary. Bioaccumulation was evaluated using multimedia bioaccumulation factors (mmBAFs) which quantified the fraction of the contaminant present in the aquatic environment that is transferred to the biota. PCB 180, a known strongly bioaccumulative chemical, was used as a benchmark. The mean mmBAF of D5 was about twice that of PCB 180 in both polycheates and flounder, while for D4 it was 6 and 14 times higher, respectively. The mmBAF of D6 was a factor 5-10 lower than that of PCB180. The comparatively strong multimedia bioaccumulation of D4 and D5, even in the absence of biomagnification, was explained by both compounds having a >100 times stronger tendency to partition into lipid rather than into organic carbon, while PCB 180 partitions to a similar extent into both matrices.

  • 18. Krogseth, Ingjerd S.
    et al.
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, Michael S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Breivik, Knut
    Hansen, Kaj M.
    Schlabach, Martin
    Occurrence and seasonality of cyclic volatile methyl siloxanes in arctic air2013Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 47, nr 1, s. 502-509Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cyclic volatile methyl siloxanes (cVMS) are present in technical applications and personal care products. They are predicted to undergo long-range atmospheric transport, but measurements of cVMS in remote areas remain scarce. An active air sampling method for decamethylcyclopentasiloxane (D5) was further evaluated to include hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), and dodecamethylcyclohexasiloxane (D6). Air samples were collected at the Zeppelin observatory in the remote Arctic (79 degrees N, 12 degrees E) with an average sampling time of 81 +/- 23 h in late summer (August-October) and 25 +/- 10 h in early winter (November-December) 2011. The average concentrations of D5 and D6 in late summer were 0.73 +/- 0.31 and 0.23 +/- 0.17 ng/m(3), respectively, and 2.94 +/- 0.46 and 0.45 +/- 0.18 ng/m(3) in early winter, respectively. Detection of D5 and D6 in the Arctic atmosphere confirms their long-range atmospheric transport. The D5 measurements agreed well with predictions from a Eulerian atmospheric chemistry-transport model, and seasonal variability was explained by the seasonality in the OH radical concentrations. These results extend our understanding of the atmospheric fate of D5 to high latitudes, but question the levels of D3 and D4 that have previously been measured at Zeppelin with passive air samplers.

  • 19.
    MacLeod, Matthew
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Genualdi, Susie
    Harner, Tom
    Scheringer, Martin
    Junge relationships in measurement data for cyclic siloxanes in air2013Inngår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 93, nr 5, s. 830-834Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In 1974, Junge postulated a relationship between variability of concentrations of gases in air at remote locations and their atmospheric residence time, and this Junge relationship has subsequently been observed empirically for a range of trace gases. Here, we analyze two previously-published datasets of concentrations of cyclic volatile methyl siloxanes (cVMS) in air and find Junge relationships in both. The first dataset is a time series of concentrations of decamethylcyclopentasiloxane (D-5) measured between January and June, 2009 at a rural site in southern Sweden that shows a Junge relationship in the temporal variability of the measurements. The second dataset consists of measurements of hexamethylcyclotrisiloxane (D-3), octamethylcyclotetrasiloxane (D-4) and D-5 made simultaneously at 12 sites in the Global Atmospheric Passive Sampling (GAPS) network that shows a Junge relationship in the spatial variability of the three cVMS congeners. We use the Junge relationship for the GAPS dataset to estimate atmospheric lifetimes of dodecamethylcyclohexasiloxane (D-6), 8:2-fluorotelomer alcohol and trichlorinated biphenyls that are within a factor of 3 of estimates based on degradation rate constants for reaction with hydroxyl radical determined in laboratory studies.

  • 20. McGoldrick, Daryl J.
    et al.
    Durham, Jeremy
    Leknes, Henriette
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Gerhards, Reinhard
    Powell, David E.
    McLachlan, Michael S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Assessing inter-laboratory comparability and limits of determination for the analysis of cyclic volatile methyl siloxanes in whole Rainbow Trout (Oncorhynchus mykiss)2011Inngår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 85, nr 8, s. 1241-1247Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cyclic volatile methyl siloxanes (cVMS) are high volume production chemicals used in a wide range of industrial and consumer products. Three cVMS compounds (D4, D5, and D6) have and are undergoing environmental risk evaluations in several countries and have been proposed for legal regulation in Canada. As interest in monitoring concentrations of these chemicals in the environment increase, there is a need to evaluate the analytical procedures for cVMS in biological matrices in order to assess the quality of data produced. The purpose of this study was to determine laboratory testing performance for measuring residues of D4, D5, and D6 in a standard set of fish homogenate samples and to estimate limits of determination for each substance. The samples sent to each laboratory consisted of homogenized whole body tissues of hatchery raised rainbow trout which were fed food fortified with D4, D5, and D6 (dosed) and trout that were fed standard food rations (control). The participants analyzed each sample using their analytical method of choice using their own standards and procedures for quantification and quality control. With a few exceptions, participating laboratories generated comparable results for D4, D5, and D6 in both the dosed and control samples having z-scores between 2 and -2. Method detection limits for the whole fish matrix were on average 2.4 ng g(-1), ww for D4, 2.3 ng g(-1), ww for D5, and 1.8 ng g(-1), ww for D6.

  • 21.
    McLachlan, Michael S.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Hansen, Kaj M.
    van Egmond, Roger
    Christensen, Jesper H.
    Skjoth, Carsten A.
    Concentrations and Fate of Decamethylcyclopentasiloxane (D-5) in the Atmosphere2010Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 44, nr 14, s. 5365-5370Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Decamethylcyclopentasiloxane (D-5) is a volatile compound used in personal care products that is released to the atmosphere in large quantities. Although D-5 is currently under consideration for regulation, there have been no field investigations of its atmospheric fate. We employed a recently developed, quality assured method to measure D-5 concentration in ambient air at a rural site in Sweden. The samples were collected with daily resolution between January and June 2009. The 05 concentration ranged from 0.3 to 9 ng m(-3), which is 1-3 orders of magnitude lower than previous reports. The measured data were compared with D-5 concentrations predicted using an atmospheric circulation model that included both OH radical and D-5 chemistry. The model was parametrized using emissions estimates and physical chemical properties determined in laboratory experiments. There was good agreement between the measured and modeled D-5 concentrations. The results show that D-5 is clearly subject to long-range atmospheric transport, but that it is also effectively removed from the atmosphere via phototransformation. Atmospheric deposition has little influence on the atmospheric fate. The good agreement between the model predictions and the field observations indicates that there is a good understanding of the major factors governing D-5 concentrations in the atmosphere.

  • 22.
    McLachlan, Michael S.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Radke, Michael
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Sobek, Anna
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Malmvärn, Anna
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Alsberg, Tomas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Arnot, Jon A.
    Brown, Trevor N.
    Wania, Frank
    Breivik, Knut
    Xu, Shihe
    Using Model-Based Screening to Help Discover Unknown Environmental Contaminants2014Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 48, nr 13, s. 7264-7271Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Of the tens of thousands of chemicals in use, only a small fraction have been analyzed in environmental samples. To effectively identify environmental contaminants, methods to prioritize chemicals for analytical method development are required. We used a high-throughput model of chemical emissions, fate, and bioaccumulation to identify chemicals likely to have high concentrations in specific environmental media, and we prioritized these for target analysis. This model-based screening was applied to 215 organosilicon chemicals culled from industrial chemical production statistics. The model-based screening prioritized several recognized organosilicon contaminants and generated hypotheses leading to the selection of three chemicals that have not previously been identified as potential environmental contaminants for target analysis. Trace analytical methods were developed, and the chemicals were analyzed in air, sewage sludge, and sediment. All three substances were found to be environmental contaminants. Phenyl-tris(trimethylsiloxy)silane was present in all samples analyzed, with concentrations of similar to 50 pg m(-3) in Stockholm air and similar to 0.5 ng g(-1) dw in sediment from the Stockholm archipelago. Tris(trifluoropropyl)trimethyl-cyclotrisiloxane and tetrakis(trifluoropropyl)tetramethyl-cyclotetrasiloxane were found in sediments from Lake Mjosa at similar to 1 ng g(-1) dw. The discovery of three novel environmental contaminants shows that models can be useful for prioritizing chemicals for exploratory assessment.

  • 23.
    Panagopoulos, Dimitri
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Jahnke, Annika
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi. Helmholtz Centre for Environmental Research, UFZ, Germany.
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    MacLeod, Matthew
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Organic Carbon/Water and Dissolved Organic Carbon/Water Partitioning of Cyclic Volatile Methylsiloxanes: Measurements and Polyparameter Linear Free Energy Relationships2015Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 49, nr 20, s. 12161-12168Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The sorption of cyclic volatile methyl siloxanes (cVMS) to organic matter has a strong influence on their fate in the aquatic environment. We report new measurements of the partition ratios between freshwater sediment organic carbon and water (K-OC) and between Aldrich humic acid dissolved organic carbon and water (K-DOC) for three cVMS, and for three polychlorinated biphenyls (PCBs) that were used as reference chemicals. Our measurements were made using a purge-and-trap method that employs benchmark chemicals to calibrate mass transfer at the air/water interface in a fugacity-based multimedia model. The measured log K-OC of octamethylcydotetrasiloxane (D-4), decamethylcyclopentasiloxane (D-5), and dodecamethylcydohexasiloxane (D-6) were 5.06, 6.12, and 7.07, and log K-DOC were 5.05, 6.13, and 6.79. To our knowledge, our measurements for K-OC of D-6 and K-DOC of D-4 and D-6 are the first reported. Polyparameter linear free energy relationships (PP-LFERs) derived from training sets of empirical data that did not include cVMS generally did not predict our measured partition ratios of cVMS accurately (root-mean-squared-error (RMSE) for logK(OC) 0.76 and for logK(DOC) 0.73). We constructed new PP-LFERs that accurately describe partition ratios for the cVMS as well as for other chemicals by including our new measurements in the existing training sets (logK(OC) RMSEcVMS: 0.09, logk(DOC) RMSEcVMS: 0.12). The PP-LFERs we have developed here should be further evaluated and perhaps recalibrated when experimental data for other siloxanes become available.

  • 24.
    Panagopoulos, Dimitri
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi. Lawrence Berkeley National Laboratory, United States.
    Jahnke, Annika
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    MacLeod, Matthew
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Temperature Dependence of the Organic Carbon/Water Partition Ratios (K-oc) of Volatile Methylsiloxanes2017Inngår i: Environmental Science and Technology Letters, ISSN 2328-8930, Vol. 4, nr 6, s. 240-245Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Knowing the temperature dependence of the organic carbon/water partition ratios (K-oc) of volatile methylsiloxanes (VMS) is required to understand their environmental fate. We measured the Koc of two linear VMS (IVMS), three cyclic VMS (cVMS), and six polychlorinated biphenyls (PCBs) at 25, 15, 10, and 5 degrees C and calculated their enthalpies and entropies of sorption to organic carbon (Delta H-oc and Delta S-oc, respectively). The Delta H-oc of VMS ranged from -79.2 to -45.8 kJ mol(-1) while the Delta H-oc of the PCBs ranged from -68.7 to -29.3 kJ mol(-1). Previously reported measurements of the enthalpy of phase change between octanol and water (Delta H-ow) for cVMS (11.3-68.8 kJ mol(-1)) differed substantially from our Delta H-oc measurements, even showing different signs (negative versus positive). Literature data of Delta H-oc and Delta H-ow for PCBs (-61 to -17 kJ mol(-1)) are closer to our measured values of Delta H-oc for the PCBs showing the same sign (negative) with differences within a factor of 2 in the majority of the cases. Comparison of all available data for PCBs and VMS indicated that there may be important differences between Delta H-oc and Delta H-ow, especially for the VMS. Therefore, assuming Delta H-oc equals Delta H-ow in environmental fate models may be a source of substantial error.

  • 25.
    Panagopoulos, Dimitri
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Jahnke, Annika
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    MacLeod, Matthew
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Temperature dependence of the organic carbon/water partition ratios (KOC) of volatile methylsiloxanesInngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851Artikkel i tidsskrift (Fagfellevurdert)
  • 26.
    Panagopoulos, Dimitri
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Jahnke, Annika
    MacLeod, Matthew
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Evaluating the salting-out effect on the organic carbon/water partition ratios (KOC and KDOC) of linear and cyclic volatile methylsiloxanes: Measurements and polyparameter linear free energy relationships2016Inngår i: Journal of Chemical and Engineering Data, ISSN 0021-9568, E-ISSN 1520-5134, Vol. 61, nr 9, s. 3098-3108Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dissolved inorganic salts influence the partitioning of organic chemicals between water and sorbents. We present new measurements of the salting-out constants (Ks) for partition ratios between water and organic carbon (KOC) and between water and dissolved organic carbon (KDOC) of three cyclic volatile methylsiloxanes (cVMS), two linear volatile methylsiloxanes (lVMS), three polychlorinated biphenyls (PCBs), and α-hexachlorocyclohexane (α-HCH). Ks, KOC, and KDOC were derived from volatilization rates of the chemicals from mixtures of water and organic carbon with varying concentrations of sodium chloride in a purge-and-trap system. KOC and KDOC values at different salinities were determined by fitting their values to reproduce observed volatilization rates using a fugacity-based multimedia model and assuming first-order kinetics for volatilization. The Ks values of cVMS and lVMS ranged from 0.16–0.76. The log KOC of cVMS and lVMS in fresh water interpolated from our measurements ranged from 5.20 to 7.36 and the log KDOC values from 5.04 to 6.72. Polyparameter linear free energy relationships (PP-LFERs) trained with data sets without measurements for siloxanes failed to accurately describe the log KOC and log KDOC of cVMS and lVMS. Including our measurements for cVMS and lVMS substantially improved the fit. PP-LFERs trained with data for Ks from solubility measurements do not describe our new measurements well regardless of whether or not they are included in the training set, which may reflect differences in the salting-out effect on partitioning to organic carbon versus on solubility.

  • 27.
    Ricklund, N.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Kierkegaard, A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    An international survey of decabromodiphenyl ethane (deBDethane) and decabromodiphenyl ether (decaBDE) in sewage sludge samples2008Inngår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 73, nr 11, s. 1799-1804Artikkel i tidsskrift (Fagfellevurdert)
  • 28.
    Ricklund, N
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Kierkegaard, A
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, M
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Decabromodiphenyl ethane in sewage sludge – A global survey.2008Inngår i: 29th Annual Meeting of SETAC North America: Tampa, 16-20 November, 2008Konferansepaper (Fagfellevurdert)
  • 29.
    Ricklund, N
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Kierkegaard, A
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, M
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Decabromodiphenyl ethane in sewage sludge – A global survey2008Inngår i: Svenskt-norskt miljökemiskt möte: Sigtuna, Sverige, 22-24 September, 2008Konferansepaper (Fagfellevurdert)
  • 30.
    Ricklund, N.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för systemekologi.
    Kierkegaard, A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, M. S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Leonards, P. E. G.
    Bioaccumulation of decabromodiphenyl ethane (dbdpe) in the Western Scheldt estuaryManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    Decabromodiphenyl ethane (dbdpe) is a brominated flame retardant (BFR) with both a similar chemical structure and similar technical applications to a chemical of recognized environmental concern, decabromodiphenyl ether (decaBDE). Bioaccumulation has been one of the most controversial issues in the risk assessment of decaBDE, but it has not been measured for dbdpe. During the last several years, dbdpe has been detected in a variety of biota, which suggests that it is bioavailable. In this work, dbdpe was analyzed together with decaBDE in a benthic and pelagic food web in the Western Scheldt estuary, an environment known to be contaminated with the two BFRs. The biota-sediment accumulation factors for benthic invertebrates were low (0.0008-0.005) for both chemicals. This weak bioaccumulation into the lowest trophic levels of the food web may have been due to a poor bioavailability of the BFRs into the estuary. Both chemicals were transferred up through the food web, but biodilution was observed, not biomagnification (BMFs 0.2-0.8). The bioaccumulation behavior of dbdpe was similar to that of decaBDE.

  • 31.
    Ricklund, N.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Kierkegaard, A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Wahlberg, C.
    Mass balance of decabromodiphenyl ethane and decabromodiphenyl ether in a WWTP2008Inngår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 74, nr 3, s. 389-394Artikkel i tidsskrift (Fagfellevurdert)
  • 32.
    Ricklund, Niklas
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, Michael S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Levels and potential sources of decabromodiphenyl ethane (dbdpe) and decabromodiphenyl ether (decaBDE) in lake sediment and marine sediment in Sweden2010Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 44, nr 6, s. 1987-1991Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Decabromodiphenyl ethane (dbdpe) is a brominated flame retardant (BFR) used as a replacement for the structurally similar decabromodiphenyl ether (decaBDE), which is a regulated environmental contaminant of concern. Dbdpe has been found in indoor dust, sewage sludge, sediment and biota, but little is known about its occurrence and distribution in the environment. In this paper, sediment was analyzed from 11 isolated Swedish lakes and along a transect running from central Stockholm through the Stockholm archipelago to the open Baltic Sea. Dbdpe was present in all samples. In lake sediment, the levels ranged from 0.23 to 11 ng/g d.wt. and were very similar to the levels of decaBDE (0.48-11 ng/g d.wt.). Since the lakes have no known point sources of BFRs, their presence in the sediments provides evidence for long range atmospheric transport and deposition. In the marine sediment, the dbdpe and decaBDE levels decreased by a factor of 20-50 over 40 km from the inner harbor to the outer archipelago. There the dbdpe and decaBDE levels were similar to the levels in nearby isolated lakes. The results indicate that contamination of the Swedish environment with dbdpe has already approached that of decaBDE, and that this contamination is primarily occurring via the atmosphere.

  • 33.
    Ricklund, Niklas
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    McLachlan, Michael S
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Wahlberg, Cajsa
    Mass balance of decabromodiphenyl ethane and decabromodiphenyl ether in a WWTP.2009Inngår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 74, nr 3, s. 389-94Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The additive flame retardant decabromodiphenyl ethane (deBDethane) has been identified in the environment, but little is known about its environmental behaviour. It is structurally similar to decabromodiphenyl ether (decaBDE), making it conceivable that it may also become an environmental contaminant of concern. In this study a mass balance of deBDethane and decaBDE was undertaken in a modern WWTP in Stockholm serving 7.05x10(5) inhabitants. Flow proportional samples of plant influent and effluent as well as daily grab samples of digested sludge were collected during two 7-day periods. All samples were analyzed with GC/HRMS using isotope labelled internal standards. The mean mass flows of deBDethane and decaBDE to the WWTP were 6.0 g per day and 55 g per day, respectively. Of this, less than 1% of both BFRs left the WWTP via the effluent, while the bulk was sequestered into the digested sludge, where the mean concentrations of deBDethane and decaBDE were 81 and 800 ng g(-1)d.wt., respectively. It is concluded that the transfer efficiency of deBDethane from the technosphere to the environment via WWTPs is similar to that of decaBDE.

  • 34.
    Safron, Andreas
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Strandell, Michael
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Macleod, Matthew
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Rate Constants and Activation Energies for Gas-Phase Reactions of Three Cyclic Volatile Methyl Siloxanes with the Hydroxyl Radical2015Inngår i: International Journal of Chemical Kinetics, ISSN 0538-8066, E-ISSN 1097-4601, Vol. 47, nr 7, s. 420-428Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Reaction with hydroxyl radicals (OH) is the major pathway for removal of cyclic volatile methyl siloxanes (cVMS) from air. We present new measurements of second-order rate constants for reactions of the cVMS octamethylcyclotetrasiloxane (D-4), decamethylcyclopentasiloxane (D-5), and dodecamethylcyclohexasiloxane (D-6) with OH determined at temperatures between 313 and 353 K. Our measurements were made using the method of relative rates with cyclohexane as a reference substance and were conducted in a 140-mL gas-phase reaction chamber with online mass spectrometry analysis. When extrapolated to 298 K, our measured reaction rate constants of D-4 and D-5 with the OH radical are 1.9 x 10(-12) (95% confidence interval (CI): (1.7-2.2) x 10(-12)) and 2.6 x 10(-12) (CI: (2.3-2.9) x 10(-12)) cm(3) molecule(-1) s(-1), respectively, which are 1.9x and 1.7x faster than previous measurements. Our measured rate constant for D-6 is 2.8 x 10(-12) (CI: (2.5-3.2) x 10(-12)) cm(3) molecule(-1) s(-1) and to our knowledge there are no comparable laboratory measurements in the literature. Reaction rates for D-5 were 33% higher than for D-4 (CI: 30-37%), whereas the rates for D-6 were only 8% higher than for D-5 (CI: 5-10%). The activation energies of the reactions of D-4, D-5, and D-6 with OH were not statistically different and had a value of 4300 +/- 2800 J/mol.

  • 35.
    Zou, Hongyan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Radke, Michael
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    MacLeod, Matthew
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    McLachlan, Michael S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Using Chemical Benchmarking to Determine the Persistence of Chemicals in a Swedish Lake2015Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 49, nr 3, s. 1646-1653Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    It is challenging to measure the persistence of chemicals under field conditions. In this work, two approaches for measuring persistence in the field were compared: the chemical mass balance approach, and a novel chemical benchmarking approach. Ten pharmaceuticals, an X-ray contrast agent, and an artificial sweetener were studied in a Swedish lake. Acesulfame K was selected as a benchmark to quantify persistence using the chemical benchmarking approach. The 95% confidence intervals of the half-life for transformation in the lake system ranged from 780-5700 days for carbamazepine to <1-2 days for ketoprofen. The persistence estimates obtained using the benchmarking approach agreed well with those from the mass balance approach (1-21% difference), indicating that chemical benchmarking can be a valid and useful method to measure the persistence of chemicals under field conditions. Compared to the mass balance approach, the benchmarking approach partially or completely eliminates the need to quantify mass flow of chemicals, so it is particularly advantageous when the quantification of mass flow of chemicals is difficult. Furthermore, the benchmarking approach allows for ready comparison and ranking of the persistence of different chemicals.

  • 36.
    Zou, Hongyan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Radke, Michael
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Kierkegaard, Amelie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    McLachlan, Michael S.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Temporal Variation of Chemical Persistence in a Swedish Lake Assessed by Benchmarking2015Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 49, nr 16, s. 9881-9888Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Chemical benchmarldng was used to investigate the temporal variation of the persistence of chemical contaminants in a Swedish lake. The chemicals studied included 12 pharmaceuticals, an artificial sweetener, and an X-ray contrast agent. Measurements were conducted in late spring, late autumn, and winter. The transformation half-life in the lake could be quantified for 7 of the chemicals. It ranged from several days to hundreds of days. For 5 of the chemicals (bezafibrate, climbazole, diclofenac, furosemide, and hydrochlorothiazide), the measured persistence was lower in late spring than in late autumn. This may have been caused by lower temperatures and/or less irradiation during late autumn. The seasonality in chemical persistence contributed to changes in chemical concentrations in the lake during the year. The impact of seasonality of persistence was compared with the impact of other important variables determining concentrations in the lake: chemical inputs and water flow/dilution. The strongest seasonal variability in chemical concentration in lake water was observed for hydrochlorothiazide (over a factor of 10), and this was attributable to the seasonality in its persistence.

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