| 1. |
- Benskin, Jonathan P., et al.
(författare)
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Perfluoroalkyl Acids in the Atlantic and Canadian Arctic Oceans
- 2012
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Ingår i: Environmental Science and Technology. - : American Chemical Society. - 0013-936X .- 1520-5851. ; 46:11, s. 5815-5823
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Tidskriftsartikel (refereegranskat)abstract
- We report here on the spatial distribution of C-4, C-6, and C-8 perfluoroalkyl sulfonates, C-6-C-14 perfluoroalkyl carboxylates, and perfluorooctanesulfonamide in the Atlantic and Arctic Oceans, including previously unstudied coastal waters of North and South America, and the Canadian Arctic Archipelago. Perfluorooctanoate (PFOA) and perfluorooctanesulfonate (PFOS) were typically the dominant perfluoroalkyl acids (PFAAs) in Atlantic water. In the midnorthwest Atlantic/Gulf Stream, sum PFAA concentrations (Sigma PFAAs) were low (77-190 pg/L) but increased rapidly upon crossing into U.S. coastal water (up to 5800 pg/L near Rhode Island). Sigma PFAAs in the northeast Atlantic were highest north of the Canary Islands (280-980 pg/L) and decreased with latitude. In the South Atlantic, concentrations increased near Rio de la Plata (Argentina/Uruguay; 350-540 pg/L Sigma PFAAs), possibly attributable to insecticides containing N-ethyl perfluorooctanesulfonamide, or proximity to Montevideo and Buenos Aires. In all other southern hemisphere locations, Sigma PFAAs were less than210 pg/L. PFOA/PFOS ratios were typically greater than= 1 in the northern hemisphere, similar to 1 near the equator, and less than= 1 in the southern hemisphere. In the Canadian Arctic, Sigma PFAAs ranged from 40 to 250 pg/L, with perfluoroheptanoate, PFOA, and PFOS among the PFAAs detected at the highest concentrations. PFOA/PFOS ratios (typically greater thangreater than1) decreased from Baffin Bay to the Amundsen Gulf; possibly attributable to increased atmospheric inputs. These data help validate global emissions models and contribute to understanding of long-range transport pathways and sources of PFAAs to remote regions.
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| 6. |
- Gouin, Todd, et al.
(författare)
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Influence of global climate change on chemical fate and bioaccumulation : The role of multimedia models
- 2013
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Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 32:1, s. 20-31
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Tidskriftsartikel (refereegranskat)abstract
- Multimedia environmental fate models are valuable tools for investigating potential changes associated with global climate change, particularly because thermodynamic forcing on partitioning behavior as well as diffusive and nondiffusive exchange processes are implicitly considered. Similarly, food-web bioaccumulation models are capable of integrating the net effect of changes associated with factors such as temperature, growth rates, feeding preferences, and partitioning behavior on bioaccumulation potential. For the climate change scenarios considered in the present study, such tools indicate that alterations to exposure concentrations are typically within a factor of 2 of the baseline output. Based on an appreciation for the uncertainty in model parameters and baseline output, the authors recommend caution when interpreting or speculating on the relative importance of global climate change with respect to how changes caused by it will influence chemical fate and bioavailability.
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| 7. |
- Hermanson, Mark H., et al.
(författare)
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Deposition History of Brominated Flame Retardant Compounds in an Ice Core from Holtedahlfonna, Svalbard, Norway
- 2010
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 44:19, s. 7405-7410
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Tidskriftsartikel (refereegranskat)abstract
- Brominated flame retardants (BFRs) have been found in Arctic wildlife, lake sediment, and air. To identify the atmospheric BFR deposition history on Svalbard, Norway, we analyzed 19 BFRs, including hexabromocyclododecane (HBCD), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), decabromodiphenyl ethane (DBDPE), pentabromoethylbenzene (PBEB), and 15 polybrominated diphenyl ether congeners (PBDE) in the upper 34 m of an ice core (representing 1953-2005) from Holtedahlfonna, the western-most ice sheet on Svalbard. All of the non-PBDE compounds were detected in nearly continuous profiles in the core. Seven PBDEs were not observed above background (28, 47, 66, 100, 99, 154, 153), while 4 were found in 1 or 2 of 6 segments (17, 85, 138, 183). BDEs-49, 71, 190, 209 had nearly continuous profiles but only BDE-209 in large amounts. The greatest inputs were HBCD and BDE-209, 910, and 320 pg cm(-2) yr(-1) from 1995-2005. DBDPE, BTBPE, and PBEB show nearly continuous input growth in recent core segments, but all were <6 pg cm(-2) yr(-1). Long-range atmospheric processes may have moved these particle-bound BFRs to the site, probably during the Arctic haze season. Average air mass trajectories over 10 years show >75% of atmospheric flow to Holtedahlfonna coming from Eurasia during haze periods (March and April).
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| 8. |
- Houde, Magali, et al.
(författare)
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POLYBROMINATED DIPHENYL ETHERS AND THEIR HYDROXYLATED ANALOGS IN PLASMA OF BOTTLENOSE DOLPHINS (TURSIOPS TRUNCATUS) FROM THE UNITED STATES EAST COAST.
- 2009
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Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 28:10, s. 2061-2068
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Tidskriftsartikel (refereegranskat)abstract
- Polybrominated diphenyl ethers (PBDEs) and hydroxylated-PBDEs (OH-PBDE) were determined in plasma of free-ranging bottlenose dolphins (Tursiops truncatus) from Charleston (CHS), South Carolina, and the Indian River Lagoon (IRL), Florida, US. Significantly lower sum (Sigma) of PBDE concentrations (sum of 12 congeners) were found in animals from the IRL [arithmetic mean: 5.454.63 ng/g wet weight (ww)] compared to CHS (3040 ng/g ww). BDE-47 was the predominant PBDE in dolphins from the IRL (50% of the SigmaPBDEs) and CHS (58%). SigmaPBDE concentrations in plasma of dolphins were negatively correlated with age at both locations. Fifteen and sixteen individual OH-PBDE congeners could be quantified in plasma of dolphins from IRL and CHS, respectively. Similar to SigmaPBDE, mean SigmaOH-PBDE concentrations were significantly higher in plasma of dolphins at CHS (1150708 pg/g ww) compared to IRL (624393 pg/g ww). The predominant congener at both locations was 6-OH-PBDE 47 (IRL: 384319 pg/g ww; CHS: 541344 pg/g ww) representing 61.5% of total SigmaOH-PBDE at IRL and 47.0% at CHS. Concentrations of SigmaOH-PBDEs were weakly negatively correlated with age in dolphins from both locations (P<0.05; IRL, R2=0.048; CHS, R2=0.021). In addition to the OH-PBDE congeners identified with technical standards, eight and four unidentified OH-PBDEs were detected and quantified respectively in animals from CHS (sum of unidentified OH-PBDEs=1.350.90 pg/g ww) and IRL (0.730.40 pg/g ww). Our results suggest that, unlike OH-PCBs, OH-PBDEs in bottlenose dolphins are minor products in plasma relative to SigmaPBDEs and a significant proportion may be a consequence of the dietary uptake of naturally produced methoxylated- and OH-PBDEs.
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| 9. |
- Muir, Derek C. G., et al.
(författare)
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Trends of legacy and new persistent organic pollutants in the circumpolar arctic : Overview, conclusions, and recommendations
- 2010
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 408:15, s. 3044-3051
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Tidskriftsartikel (refereegranskat)abstract
- This article provides an overview of key findings in the reviews in this special issue on the assessment of persistent organic pollutants (POPS) under the Arctic Monitoring and Assessment Program (AMAP), identifies knowledge gaps, and presents conclusions and recommendations for future work. The articles in this special issue summarize the peer reviewed literature and selected technical reports on trends of concentrations and possible biological effects of POPs in the Arctic published up to early 2009. Crown Copyright
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| 10. |
- Ruggirello, Rachel M., et al.
(författare)
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Current use and legacy pesticide deposition to ice caps on Svalbard, Norway
- 2010
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Ingår i: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 115, s. D18308-
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Tidskriftsartikel (refereegranskat)abstract
- Transport and deposition of current use (CUP) and legacy pesticides (LP) and residual products to the Arctic have been documented in abiotic matrices. These observations show that some "low-persistence" pesticides with high OH center dot reaction rates are stable enough to accumulate in a polar environment. In 2005, we drilled an ice core on Holtedahlfonna, one of the major ice fields on Svalbard, Norway to measure the input of 47 CUPs and 17 LPs to a high-elevation abiotic environment with no local pesticide sources. Of these, 9 CUPs and 12 LPs were observed in at least one of 6 core segments dating to 1953: 15 of these were found in enough core segments to reveal time-related trends. CUPs often observed included chlorpyrifos, dacthal, alpha- and beta- endosulfan, endosulfan sulfate, trifluralin, and gamma-HCH. LPs most often observed included methoxychlor, alpha- and gamma-chlordane, cis- and trans- nonachlor, endrin, dieldrin, and p, p'-DDE. In our comparison of core burdens at Holtedahlfonna and Austfonna (220 km ENE from Holtedahlfonna), we found twice as many CUPs at Austfonna along with greater amounts of dieldrin, methoxychlor, alpha-endosulfan and chlorpyrifos suggesting different accumulation processes or sources. Air mass back trajectories over a 10-year period of comparison between sites (1986-1995) show air mass flow from Eurasia 74% of the time to Austfonna and 45% to Holtedahfonna which may account for some of the differences.
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| 11. |
- Vorkamp, Katrin, et al.
(författare)
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Influences of climate change on long-term time series of persistent organic pollutants (POPs) in Arctic and Antarctic biota
- 2022
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Ingår i: Environmental Science. - : Royal Society of Chemistry (RSC). - 2050-7887 .- 2050-7895. ; 24:10, s. 1643-1660
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Forskningsöversikt (refereegranskat)abstract
- Time series of contaminants in the Arctic are an important instrument to detect emerging issues and to monitor the effectiveness of chemicals regulation, based on the assumption of a direct reflection of changes in primary emissions. Climate change has the potential to influence these time trends, through direct physical and chemical processes and/or changes in ecosystems. This study was part of an assessment of the Arctic Monitoring and Assessment Programme (AMAP), analysing potential links between changes in climate-related physical and biological variables and time trends of persistent organic pollutants (POPs) in Arctic biota, with some additional information from the Antarctic. Several correlative relationships were identified between POP temporal trends in freshwater and marine biota and physical climate parameters such as oscillation indices, sea-ice coverage, temperature and precipitation, although the mechanisms behind these observations remain poorly understood. Biological data indicate changes in the diet and trophic level of some species, especially seabirds and polar bears, with consequences for their POP exposure. Studies from the Antarctic highlight increased POP availability after iceberg calving. Including physical and/or biological parameters in the POP time trend analysis has led to small deviations in some declining trends, but did generally not change the overall direction of the trend. In addition, regional and temporary perturbations occurred. Effects on POP time trends appear to have been more pronounced in recent years and to show time lags, suggesting that climate-related effects on the long time series might be gaining importance.
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| 12. |
- Wang, Zhanyun, et al.
(författare)
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Enhancing Scientific Support for the Stockholm Convention’s Implementation : An Analysis of Policy Needs for Scientific Evidence
- 2022
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 56:5, s. 2936-2949
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Tidskriftsartikel (refereegranskat)abstract
- The Stockholm Convention is key to addressing the global threats of persistent organic pollutants (POPs) to humanity and the environment. It has been successful in identifying new POPs, but its national implementation remains challenging, particularly by low- and middle-income Parties. Concerted action is needed to assist Parties in implementing the Convention’s obligations. This analysis aims to identify and recommend research and scientific support needed for timely implementation of the Convention. We aim this analysis at scientists and experts from a variety of natural and social sciences and from all sectors (academia, civil society, industry, and government institutions), as well as research funding agencies. Further, we provide practical guidance to scientists and experts to promote the visibility and accessibility of their work for the Convention’s implementation, followed by recommendations for sustaining scientific support to the Convention. This study is the first of a series on analyzing policy needs for scientific evidence under global governance on chemicals and waste.
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| 13. |
- Yeung, Leo W. Y., 1981-, et al.
(författare)
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Perfluoroalkyl substances and extractable organic fluorine in surface sediments and cores from Lake Ontario
- 2013
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Ingår i: Environment International. - : Elsevier. - 0160-4120 .- 1873-6750. ; 59, s. 389-397
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Tidskriftsartikel (refereegranskat)abstract
- Fourteen perfluoroalkyl substances (PFASs) including short-chain perfluorocarboxylates (PFCAs, C4-C6) and perfluoroalkane sulfonates (PFSAs, C4 and C6) were measured in surface sediment samples from 26 stations collected in 2008 and sediment core samples from three stations (Niagara, Mississauga, and Rochester basins) collected in 2006 in Lake Ontario. Perfluorooctanesulfonate (PFOS), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA), and perfluoroundecanoate (PFUnDA) were detected in all 26 surface sediment samples, whereas perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonamide (FOSA), perfluorododecanoate (PFDoDA) and perfluorobutanoate (PFBA) were detected in over 70% of the surface sediment samples. PFOS was detected in all of the sediment core samples (range: 0.492-30.1ngg-1 d.w.) over the period 1952-2005. The C8 to C11 PFCAs, FOSA, and PFBA increased in early 1970s. An overall increasing trend in sediment PFAS concentrations/fluxes from older to more recently deposited sediments was evident in the three sediment cores. The known PFCAs and PFSAs accounted for 2-44% of the anionic fraction of the extractable organic fluorine in surface sediment, suggesting that a large proportion of fluorine in this fraction remained unknown. Sediment core samples collected from Niagara basin showed an increase in unidentified organic fluorine in recent years (1995-2006). These results suggest that the use and manufacture of fluorinated organic compounds other than known PFCAs and PFSAs has diversified and increased.
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| 14. |
- Yuan, Bo, et al.
(författare)
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Chlorines Are Not Evenly Substituted in Chlorinated Paraffins : A Predicted NMR Pattern Matching Framework for Isomeric Discrimination in Complex Contaminant Mixtures
- 2020
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Ingår i: Environmental Science and Technology Letters. - : American Chemical Society (ACS). - 2328-8930. ; 7:7, s. 496-503
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Tidskriftsartikel (refereegranskat)abstract
- Chlorinated paraffins (CPs) can be mixtures of nearly a half-million possible isomers. Despite the extensive use of CPs, their isomer composition and effects on the environment remain poorly understood. Here, we reveal the isomeric distributions of nine CP mixtures with single-chain lengths (C-14/15) and varying degrees of chlorination. The molar distribution of CnH2n+2-mClm in each mixture was determined using high-resolution mass spectrometry (MS). Next, the mixtures were analyzed by applying both one-dimensional H-1, C-13 and two-dimensional nuclear magnetic resonance (NMR) spectroscopy. Due to substantially overlapping signals in the experimental NMR spectra, direct assignment of individual isomers was not possible. As such, a new NMR spectral matching approach that used massive NMR databases predicted by a neural network algorithm to provide the top 100 most likely structural matches was developed. The top 100 isomers appear to be an adequate representation of the overall mixture. Their modeled physicochemical and toxicity parameters agree with previous experimental results. Chlorines are not evenly distributed in any of the CP mixtures and show a general preference at the third carbon. The approach described here can play a key role in understanding of complex isomeric mixtures such as CPs that cannot be resolved by MS alone.
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