39 research outputs found

    Atmospheric concentrations and gas/particle partitioning of neutral poly- and perfluoroalkyl substances in northern German coast

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    Total 58 high volume air samples were collected in Busum, Germany, from August 2011 to October 2012 to investigate air concentrations of 12 per- and polyfluoroalkyl substances (PFASs) and their gas/particle partitioning. The total concentration (vapor plus particle phases) of the 12 PFASs (Sigma PFASs) ranged from 8.6 to 155 pg/m(3) (mean: 41 pg/m(3)) while fluorotelomer alcohols 8:2 (8:2 FTOH) dominated all samples accounting for 61.9% of Sigma PFASs and the next most species were 10:2 FTOH (12.7%). Air mass back trajectory analysis showed that atmospheric PFASs in most samples were from long range atmospheric transport processes and had higher ratios of 8:2 to 6:2 FTOH compared to the data obtained from urban/industrial sources. Small portion of particle PFASs in the atmosphere was observed and the average percent to Sigma PFASs was 2.0%. The particle-associated fractions of different PFASs decreased from perfluorooctane sulfonamidoethanols (FOSEs) (15.5%) to fluorotelomer acrylates (FTAs) (7.6%) to perfluorooctane sulfonamides (FOSAs) (3.1%) and F10Hs (1.8%), indicating the functional group obviously influenced their gas/particle partitioning. For neutral compounds with acid dissociation constant (PKa) > 7.0 (i.e., FTOHs, FOSEs and FOSAs), a significant log-linear relationship was observed between their gas/particle partition coefficients (K-SP) and vapor pressures (p(L)(o)), suggesting the gas/particle partitioning of neutral PFASs agreed with the classical logK(SP)-logp(L)(o) relation. Due to the pK(a) values of 6:2 and 8:2 FTA below the typical environmental pH conditions, they mainly exist as ionic form in aerosols, and the corrected logK(SP) (neutral form) were considerably lower than those of FTOHs, FOSEs and FOSAs with similar vapor pressures. Considering the strong partitioning potential to aqueous phases for ionic PFASs at higher pH values, a need exists to develop a model taking account of the ad/absorption mechanism to the condensed phase of aerosols for ionizable PFASs (e.g., FTAs). (C) 2014 Elsevier Ltd. All rights reserved

    Neutral poly- and perfluoroalkyl substances in air and seawater of the North Sea

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    Concentrations of neutral poly- and perfluoroalkyl substances (PFASs), such as fluorotelomer alcohols (FTOHs), perfluoroalkane sulfonamides (FASAs), perfluoroalkane sufonamidoethanols (FASEs), and fluorotelomer acrylates (FTACs), have been simultaneously determined in surface seawater and the atmosphere of the North Sea. Seawater and air samples were taken aboard the German research vessel Heincke on the cruise 303 from 15 to 24 May 2009. The concentrations of FTOHs, FASAs, FASEs, and FTACs in the dissolved phase were 2.6-74, < 0.1-19, < 0.1-63, and < 1.0-9.0 pg L-1, respectively. The highest concentrations were determined in the estuary of the Weser and Elbe rivers and a decreasing concentration profile appeared with increasing distance from the coast toward the central part of the North Sea. Gaseous FTOHs, FASAs, FASEs, and FTACs were in the range of 36-126, 3.1-26, 3.7-19, and 0.8-5.6 pg m(-3), which were consistent with the concentrations determined in 2007 in the North Sea, and approximately five times lower than those reported for an urban area of Northern Germany. These results suggested continuous continental emissions of neutral PFASs followed by transport toward the marine environment. Air-seawater gas exchanges of neutral PFASs were estimated using fugacity ratios and the two-film resistance model based upon paired air-seawater concentrations and estimated Henry's law constant values. Volatilization dominated for all neutral PFASs in the North Sea. The air-seawater gas exchange fluxes were in the range of 2.5 x 10(3)-3.6 x 10(5) pg m(-2) for FTOHs, 1.8 x 10(2)-1.0 x 10(5) pg m(-2) for FASAs, 1.1 x 10(2)-3.0 x 10(5) pg m(-2) for FASEs and 6.3 x 10(2)-2.0 x 10(4) pg m(-2) for FTACs, respectively. These results suggest that the air-seawater gas exchange is an important process that intervenes in the transport and fate for neutral PFASs in the marine environment

    Brominated flame retardants and Dechloranes in European and American eels from glass to silver life stages

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    The populations of American (Anguilla rostrata) and European eels (Anguilla anguilla) have been declining rapidly in the last decades. Organic contaminants are suspected to be one of the possible causes for the decline; however, so far there have been few investigations of the uptake of specific compounds by different life cycle stages (e.g. freshwater or marine stage) and how the contamination patterns develop throughout the eel's life cycle. In the present study we measured concentrations of polybrominated diphenylethers (PBDEs), alternate brominated flame retardants (alternate BFRs) and Dechloranes (Decs) in different life stages of European and American eels to compare the contamination patterns and their development throughout the eel's life cycle. In general, concentrations of flame retardants (FRs) were similar to or higher in American than in European eels, and a greater number of FRs were detected. PBDE congeners that are characteristic of the Penta-PBDE formulation were the most abundant FRs in all adult eels as well as American glass eels. In European glass eels the alternate BFR 2,3-dibromopropy1-2,4,6-tribromophenylether (DPTE) and Dechlorane Plus were the dominating FRs, with average concentrations of 1.1 +/- 0.31 ng g(-1) ww and up to 0.32 ng g(-1) ww respectively. Of the PBDEs BDE-183 was the most abundant congener in European glass eels. Low concentrations (less than 10% of the total contamination) of Tetra and Penta-PBDEs in juvenile European eels indicated that bans of technical Penta-PBDE in the European Union are effective. Enrichment of PBDEs was observed over the life stages of both European and American eels. However, a greater relative contribution of PBDEs to the sum FR contamination in American eels indicated an ongoing exposure to these substances. High contributions of alternate BFRs in juvenile eels indicated an increased use of these substances in recent years. Concentrations seemed to be driven primarily by location, rather than life stage or age. (C) 2013 Elsevier Ltd. All rights reserved

    Impact of antithymocyte globulin doses in reduced intensity conditioning before allogeneic transplantation from matched sibling donor for patients with acute myeloid leukemia: a report from the acute leukemia working party of European group of Bone Marrow Transplantation.

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    Antithymocyte globulin (ATG) is commonly used for graft-vs.-host disease (GVHD) prophylaxis in unrelated donor allogeneic transplantation (Allo-HSCT). However, its use is still controversial in matched sibling donor (MSD) Allo-HSCT, notably after reduced intensity conditioning (RIC). ATG dose may influence the outcome, explaining in part the discordant conclusions in MSD Allo-HSCT. We, therefore, analyzed the impact of ATG doses in patients with acute myeloid leukemia in first complete remission undergoing RIC Allo-HSCT from a MSD. We analyzed 234 patients from the EBMT registry and compared outcome according to given ATG dose (high dose: >/= 6 mg/kg, n = 39 or low dose: < 6 mg/kg, n = 195). No difference was found in the cumulative incidence of acute (grade 2-4: high dose vs. low dose: 21% vs. 13%, p = 0.334; adjusted hazard ratio (HR): 1.20, p = 0.712) and chronic GVHD (extensive: high dose vs. low dose: 19% vs. 18%, p = 0.897; adjusted HR: 1.01, p = 0.980). In contrast, high dose of ATG significantly increased the incidence of relapse (52% vs. 26%, p = 0.011; adjusted HR: 1.31, p = 0.001) leading to impaired outcome (HR progression-free survival (PFS): 1.23, p = 0.002; HR overall survival (OS): 1.17, p = 0.029; HR GVHD and relapse-free survival (GRFS): 1.20, p = 0.005). We conclude that an ATG dose <6 mg/kg is sufficient for GVHD prophylaxis, while higher doses impair disease control and outcome

    Natives and aliens: who and what belongs in nature and in the nation?

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    The distinction between native and alien species is a main tenet of various natural sciences, invasion biology in particular. However, it is also a contested one, as it does not reflect the biological features of a species, but only its place of origin and migration history. The present article offers a brief genealogy of the native/alien divide and argues that central to this binary is a national thinking which divides the world into distinct (national) units, enclosed by (natural) borders, with a unique (native) population attached to these spatial units. The article illustrates this argument by looking at two interrelated processes: the nationalisation of nature, by which the national thinking intervenes as an organising principle in determining ecological inclusion/exclusion, and the naturalisation of the nation, through which the nation is given an ontological status. Taken together these two processes confirm the continuing salience of the nation as a b-ordering principle actively constituting both the social and natural world, also in times of anthropogenic changes and increasing people’s mobility

    HLA-Mismatched Donors in Patients with Myelodysplastic Syndrome: An EBMT Registry Analysis

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    Recently, haploidentical transplantation (haplo) using post-transplant cyclophosphamide (PTCy) has been reported to give very encouraging results in patients with hematological malignancies. Patients who have no HLA-matched donor currently have the choice between a mismatched unrelated donor, an unrelated cord blood (CB) donor, and a haploidentical related donor. The aim of our study is to compare the outcome of patients with myelodysplastic syndrome (MDS) who have been transplanted from a haploidentical donor using PTCy, an HLA-mismatched unrelated donor (marrow or peripheral blood stem cells), or an unrelated mismatched CB donor. A total of 833 MDS patients from the European Group for Blood and Marrow Transplantation (EBMT) registry, transplanted between 2011 and 2016, were identified. The potential benefit of haplo was compared with mismatched unrelated and CB donors in an adjusted and weighted model taking into account potential confounders and other prognostic variables. Haplo was at lower risk of acute graft-versus-host disease (GVHD) than mismatched unrelated donor (P = .010) but at similar risk than CB. Progression-free survival was better after haplo (versus mismatched unrelated, P = .056; versus CB, P = .003) and overall survival tended to be superior after haplo (versus mismatched unrelated, P = .082; versus CB, P = .002). Nonrelapse mortality was not significantly different between haplo and mismatched unrelated donors. Relapse risk was not influenced by the type of donor. In conclusion, patients with MDS from the EBMT registry receiving hematopoietic stem cell transplantation from a haplo donor have significantly better outcome than those receiving hematopoietic stem cell transplantation from a CB donor and at least similar or better outcome than with a mismatched unrelated donor. Prospective studies comparing the type of donors will be needed to confirm this assumption
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