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A critical assessment of the environmental fate of linear and cyclic volatile methylsiloxanes using multimedia fugacity models.

https://arctichealth.org/en/permalink/ahliterature287996
Source
Environ Sci Process Impacts. 2018 Jan 24;20(1):183-194
Publication Type
Article
Date
Jan-24-2018
Author
Dimitri Panagopoulos
Matthew MacLeod
Source
Environ Sci Process Impacts. 2018 Jan 24;20(1):183-194
Date
Jan-24-2018
Language
English
Publication Type
Article
Abstract
We apply multimedia models to systematically evaluate the fate profile of cyclic volatile methyl siloxanes (VMS) D4, D5 and D6, and the linear VMS L4 and L5 using recently reported measurements of their partition ratios between organic carbon and water (KOC), their salting out constants (Ks), and their enthalpy of sorption to organic carbon (?HOC). Our assessment follows a multi-stage strategy where the environmental fate of the chemicals is explored in generic regional models with increasing fidelity to the real system and in a region-specific model. Modeled emissions of VMS to air remained in air and were degraded or advected out of the system with overall residence times ranging from 2.4 to 2.5 days, while emissions to water resulted in accumulation in sediment and longer residence times ranging from 29.5 to 1120 days. When emitted to water the modeled residence times of VMS in the sediment exceeded the REACH criterion for persistence in freshwater sediments. Reported KOC measurements for D5 differ by 1 log unit, which results in a 500-day difference in the overall residence times calculated in the generic regional modeling. In the specific-region modeling assessment for Adventfjorden, Svalbard in Norway, the different KOC measurements of D5 resulted in a 200-day difference in overall residence times. Model scenarios that examined combinations of previously published ?HOC or enthalpy of phase change between octanol and water (?HOW) for D5 in combination with the range of the KOC measurements resulted in 1100-days difference in overall residence times. Our results demonstrate that residence times of VMS in aquatic systems are highly sensitive to their degree of sorption to organic carbon, and that residence times of VMS likely exceed several persistence criteria and therefore they cannot be considered as non-persistent.
PubMed ID
29300410 View in PubMed
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Emissions, fate and transport of persistent organic pollutants to the Arctic in a changing global climate.

https://arctichealth.org/en/permalink/ahliterature116763
Source
Environ Sci Technol. 2013 Mar 5;47(5):2323-30
Publication Type
Article
Date
Mar-5-2013
Author
Henry Wöhrnschimmel
Matthew MacLeod
Konrad Hungerbuhler
Author Affiliation
Institute for Chemical and Bioengineering, Swiss Federal Institute of Technology Zurich , Wolfgang-Pauli Strasse 10, 8093 Zurich, Switzerland.
Source
Environ Sci Technol. 2013 Mar 5;47(5):2323-30
Date
Mar-5-2013
Language
English
Publication Type
Article
Keywords
Air - analysis
Arctic Regions
Climate change
Environmental Pollutants - analysis
Humans
Models, Theoretical
Organic Chemicals - analysis
Water - chemistry
Abstract
Climate change is expected to alter patterns of human economic activity and the associated emissions of chemicals, and also to affect the transport and fate of persistent organic pollutants (POPs). Here, we use a global-scale multimedia chemical fate model to analyze and quantify the impact of climate change on emissions and fate of POPs, and their transport to the Arctic. First, climate change effects under the SRES-A2 scenario are illustrated using case-studies for two well-characterized POPs, PCB153, and a-HCH. Then, we model the combined impact of altered emission patterns and climatic conditions on environmental concentrations of potential future-use substances with a broad range of chemical properties. Starting from base-case generic emission scenarios, we postulate changes in emission patterns that may occur in response to climate change: enhanced usage of industrial chemicals in an ice-free Arctic, and intensified application of agrochemicals due to higher crop production and poleward expansion of potential arable land. We find both increases and decreases in concentrations of POP-like chemicals in the Arctic in the climate change scenario compared to the base-case climate. During the phase of ongoing primary emissions, modeled increases in Arctic contamination are up to a factor of 2 in air and water, and are driven mostly by changes in emission patterns. After phase-out, increases are up to a factor of 2 in air and 4 in water, and are mostly attributable to changes in transport and fate of chemicals under the climate change scenario.
PubMed ID
23362961 View in PubMed
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Equilibrium sampling to determine the thermodynamic potential for bioaccumulation of persistent organic pollutants from sediment.

https://arctichealth.org/en/permalink/ahliterature267810
Source
Environ Sci Technol. 2014 Oct 7;48(19):11352-9
Publication Type
Article
Date
Oct-7-2014
Author
Annika Jahnke
Matthew MacLeod
Håkan Wickström
Philipp Mayer
Source
Environ Sci Technol. 2014 Oct 7;48(19):11352-9
Date
Oct-7-2014
Language
English
Publication Type
Article
Keywords
Animals
Bivalvia
Environmental monitoring
Fishes
Geologic Sediments - analysis
Hexachlorobenzene - analysis
Lakes
Lipids - chemistry
Polychlorinated biphenyls - analysis
Sweden
Thermodynamics
Abstract
Equilibrium partitioning (EqP) theory is currently the most widely used approach for linking sediment pollution by persistent hydrophobic organic chemicals to bioaccumulation. Most applications of the EqP approach assume (I) a generic relationship between organic carbon-normalized chemical concentrations in sediments and lipid-normalized concentrations in biota and (II) that bioaccumulation does not induce levels exceeding those expected from equilibrium partitioning. Here, we demonstrate that assumption I can be obviated by equilibrating a silicone sampler with chemicals in sediment, measuring chemical concentrations in the silicone, and applying lipid/silicone partition ratios to yield concentrations in lipid at thermodynamic equilibrium with the sediment (CLip?Sed). Furthermore, we evaluated the validity of assumption II by comparing CLip?Sed of selected persistent, bioaccumulative and toxic pollutants (polychlorinated biphenyls (PCBs) and hexachlorobenzene (HCB)) to lipid-normalized concentrations for a range of biota from a Swedish background lake. PCBs in duck mussels, roach, eel, pikeperch, perch and pike were mostly below the equilibrium partitioning level relative to the sediment, i.e., lipid-normalized concentrations were =CLip?Sed, whereas HCB was near equilibrium between biota and sediment. Equilibrium sampling allows straightforward, sensitive and precise measurement of CLip?Sed. We propose CLip?Sed as a metric of the thermodynamic potential for bioaccumulation of persistent organic chemicals from sediment useful to prioritize management actions to remediate contaminated sites.
PubMed ID
25184484 View in PubMed
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Exposure assessment at a PCDD/F contaminated site in Sweden--field measurements of exposure media and blood serum analysis.

https://arctichealth.org/en/permalink/ahliterature98958
Source
Environ Sci Pollut Res Int. 2010 Jan;17(1):26-39
Publication Type
Article
Date
Jan-2010
Author
Annika Aberg
Mats Tysklind
Tohr Nilsson
Matthew MacLeod
Annika Hanberg
Rolf Andersson
Sture Bergek
Richard Lindberg
Karin Wiberg
Author Affiliation
Department of Chemistry, Umeå University, SE-901 87, Umeå, Sweden.
Source
Environ Sci Pollut Res Int. 2010 Jan;17(1):26-39
Date
Jan-2010
Language
English
Publication Type
Article
Keywords
Benzofurans - blood - metabolism
Environmental Exposure - adverse effects - analysis
Environmental monitoring
Food contamination - analysis
Food Supply - classification
Geography
Humans
Public Health
Risk assessment
Soil Pollutants - analysis - blood - metabolism
Sweden
Tetrachlorodibenzodioxin - analogs & derivatives - analysis - blood - metabolism
Water Pollutants, Chemical - analysis - blood - metabolism
Abstract
BACKGROUND, AIM, AND SCOPE: The main pathway for human exposure to the highly toxic polychlorinated-p-dioxins and polychlorinated furans [polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs)] is via dietary intake. Other exposure pathways may, however, be important in close proximity to point sources, such as wood preservation sites, where PCDD/F contaminated chlorophenols (CP) were previously used. In this study, a heavily PCDD/F contaminated CP saw mill site in Sweden was investigated. Human exposure through a broad spectrum of exposure pathways was assessed. Such studies are in demand since the question whether contaminated sites represent a current or future risk can only be answered by detailed site-specific risk assessments. MATERIALS AND METHODS: Sampling of exposure media (soil, air, groundwater, raspberries, carrots, potatoes, grass, milk, eggs, and chicken fodder) was made. Exposure media concentrations and congener distribution patterns were used to investigate the mobilization of PCDD/Fs from soil to the environment and to calculate exposure levels for adults. Blood serum levels from site-exposed and control individuals were also analyzed. RESULTS: Congener distribution patterns at the site were generally dominated by a specific marker congener (1234678-HpCDF), which is highly abundant in the polluted soil. The dioxin toxic equivalents (TEQ) concentrations were notably elevated as compared to national reference samples for most exposure media, and the marker congener was a major contributor to increased TEQ levels. There were also indications of soil-to-air volatilization of tetra- and penta-CDD/Fs. People who participated in the restoration of a contaminated building showed higher levels of 1234678-HpCDF compared to controls, and calculated exposure levels suggest that several site-specific exposure routes may be of importance for the daily intake of PCDD/F. CONCLUSIONS, RECOMMENDATIONS, AND PERSPECTIVES: Despite low mobility of higher chlorinated PCDD/Fs, these contaminants were transferred from the polluted soil to the surroundings and into human tissue. The extent of increased exposure from contaminated sites depends on the PCDD/F source strength of the soil, composition of the pollution, human activities, and dietary patterns of the residents. Impact from the contaminated soil on other exposure media was seen also for areas with low to moderate soil contamination. In the future, not only the levels of PCDD/F soil pollution but also the composition must be considered in risk assessments of contaminated sites.
PubMed ID
19641944 View in PubMed
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Investigating the presence and persistence of volatile methylsiloxanes in Arctic sediments.

https://arctichealth.org/en/permalink/ahliterature306959
Source
Environ Sci Process Impacts. 2020 Apr 29; 22(4):908-917
Publication Type
Journal Article
Date
Apr-29-2020
Author
Dimitri Panagopoulos Abrahamsson
Nicholas Alexander Warner
Liisa Jantunen
Annika Jahnke
Fiona Wong
Matthew MacLeod
Author Affiliation
Department of Environmental Science and Analytical Chemistry, ACES, Stockholm University, Svante Arrhenius väg 8, SE-114 18 Stockholm, Sweden. drdimitripanagopoulos@gmail.com.
Source
Environ Sci Process Impacts. 2020 Apr 29; 22(4):908-917
Date
Apr-29-2020
Language
English
Publication Type
Journal Article
Keywords
Arctic Regions
Canada
Environmental monitoring
Geologic sediments
Siloxanes
Waste Water
Water Pollutants, Chemical
Abstract
Volatile methylsiloxanes (VMS) have been identified as contaminants of emerging concern in aquatic systems. Here, we report on the presence of VMS in sediment and wastewater from Arctic regions in 2014 to 2016 and model their persistence in Adventfjorden in Longyearbyen, Svalbard. Total concentrations of VMS in sediment were dominated by D4 and D5 and ranged from 0.0024 to 1.7 ng g-1 at Svalbard (Longyearbyen), from 4.0 to 43 ng g-1 in Greenland (Nuuk) and from 0.19 to 21 ng g-1 in the Canadian Archipelago. Concentrations in wastewater samples from Svalbard ranged from 12 to 156 ng L-1. Large variability in reported values of the partition ratio between organic carbon and water (KOC) and enthalpy of sorption (?HOC; often estimated from enthalpy of phase change between octanol and water, ?HOW) of VMS has resulted in high uncertainty in evaluating persistence in aquatic systems. We evaluated previously reported KOC and ?HOC values from the literature in predicting measured VMS concentrations in sediment and wastewater in scenarios using a fugacity-based multimedia model for VMS concentrations in Svalbard. We tested two different model scenarios: (1) KOC and ?HOW measurements for three cyclic VMS previously reported by Kozerski et al. (Environ. Toxicol. Chem., 2014, 33, 1937-1945) and Xu and Kropscott (Environ. Chem., 2014, 33, 2702-2710) and (2) the KOC and ?HOC measurements from Panagopoulos et al. (Environ. Sci. Technol., 2015, 49, 12161-12168 and Environ. Sci. Technol. Lett., 2017, 4(6), 240-245). Concentrations of VMS in sediment predicted from concentrations in wastewater in scenario 2 were in good agreement with measured concentrations, whereas in scenario 1, predicted concentrations were 2 to 4 orders of magnitude lower. Such large discrepancies indicate that the differences in the predicted concentrations are more likely to be attributed to KOC and ?HOC than to uncertainty in environmental parameters or emission rates.
PubMed ID
32048673 View in PubMed
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No measurable "cleaning" of polychlorinated biphenyls from Rainbow Trout in a 9 week depuration study with dietary exposure to 40% polyethylene microspheres.

https://arctichealth.org/en/permalink/ahliterature281184
Source
Environ Sci Process Impacts. 2016 Jul 13;18(7):788-95
Publication Type
Article
Date
Jul-13-2016
Author
Christoph Daniel Rummel
Margaretha Adolfsson-Erici
Annika Jahnke
Matthew MacLeod
Source
Environ Sci Process Impacts. 2016 Jul 13;18(7):788-95
Date
Jul-13-2016
Language
English
Publication Type
Article
Keywords
Animals
Environmental Exposure
Microspheres
Oncorhynchus mykiss - metabolism
Polychlorinated Biphenyls - metabolism
Polyethylene - analysis
Sweden
Water Pollutants, Chemical - metabolism
Abstract
Persistent hydrophobic chemicals sorbed to plastic can be transferred to fish and other aquatic organisms upon ingestion. However, ingestion of plastic could also lead to enhanced elimination of these chemicals if the plastic is less contaminated than the fish. Here, we attempted to measure the influence of ingestion of uncontaminated polyethylene microspheres on the depuration rates of polychlorinated biphenyls (PCBs) in an in vivo fish feeding experiment. Rainbow trout were given feed contaminated with PCBs for two consecutive days, then clean feed for three days to allow for egestion of the contaminated food. A control group of fish were then fed ordinary food pellets and a treatment group were fed pellets that additionally contained 40% by weight polyethylene microspheres. Condition factors and growth rates in both groups were similar, indicating no negative effect of the plastic microspheres on the nutritional status of the fish. Fish were sampled after zero, three, six and nine weeks, homogenized, solvent-extracted and analyzed by GC/MS. PCB concentrations declined in both groups at a rate consistent with growth dilution. There was no significant difference in the elimination rate constants between the control and treatment group, indicating that ingestion of uncontaminated plastic did not cause a measurable enhancement of depuration of PCBs by the fish in this study.
PubMed ID
27312800 View in PubMed
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Performance of the CalTOX fate and exposure model in a case study for a dioxin-contaminated site.

https://arctichealth.org/en/permalink/ahliterature265405
Source
Environ Sci Pollut Res Int. 2015 Jun;22(11):8719-27
Publication Type
Article
Date
Jun-2015
Author
Annika Åberg
Matthew MacLeod
Karin Wiberg
Source
Environ Sci Pollut Res Int. 2015 Jun;22(11):8719-27
Date
Jun-2015
Language
English
Publication Type
Article
Keywords
Animals
Benzofurans - analysis
Cattle
Daucus carota - chemistry
Eggs - analysis
Environmental Exposure - analysis
Food contamination - analysis
Hazardous Waste Sites
Humans
Meat - analysis
Milk - chemistry
Models, Theoretical
Poaceae - chemistry
Risk assessment
Soil Pollutants - analysis
Solanum tuberosum - chemistry
Sweden
Tetrachlorodibenzodioxin - analogs & derivatives - analysis
Abstract
Soil with high levels of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) is found at contaminated sites all over the world. Transfer of PCDD/Fs from contaminated soil to the food chain could lead to elevated human exposure. As a complement to available monitoring data, multimedia fate and exposure modeling can be applied to support risk assessment of sites with PCDD/F contaminated soil. In this study, we evaluated the performance of the CalTOX fate and exposure model for 2,3,7,8-substituted PCDD/Fs against measured concentrations in air, soil, grass, carrots, potatoes, milk, meat, and eggs from a contaminated site in northern Sweden. The calculated total toxic equivalent (TEQ) concentrations agree with measurements within a factor of 10 for all exposure media but one. Results for individual congeners demonstrated that the model did not always perform well at describing key processes that mobilize PCDD/Fs out of soils, such as transfer into root crops and ingestion of soil by chickens. Uncertainty in only a small subset of input parameters affects the model output. Improved information and models describing transfer of soil particles onto leafy vegetation by rain splash and biotransfer factors for PCDD/Fs to milk, meat, and eggs are particular research needs to reduce uncertainties in model-based assessments.
PubMed ID
25572268 View in PubMed
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Polychlorinated biphenyls (PCBs) as sentinels for the elucidation of Arctic environmental change processes: a comprehensive review combined with ArcRisk project results.

https://arctichealth.org/en/permalink/ahliterature299344
Source
Environ Sci Pollut Res Int. 2018 Aug; 25(23):22499-22528
Publication Type
Journal Article
Review
Date
Aug-2018
Author
Pernilla Carlsson
Knut Breivik
Eva Brorström-Lundén
Ian Cousins
Jesper Christensen
Joan O Grimalt
Crispin Halsall
Roland Kallenborn
Khaled Abass
Gerhard Lammel
John Munthe
Matthew MacLeod
Jon Øyvind Odland
Janet Pawlak
Arja Rautio
Lars-Otto Reiersen
Martin Schlabach
Irene Stemmler
Simon Wilson
Henry Wöhrnschimmel
Author Affiliation
Norwegian Institute for Water Research (NIVA), 0349, Oslo, Norway. pernilla.carlsson@niva.no.
Source
Environ Sci Pollut Res Int. 2018 Aug; 25(23):22499-22528
Date
Aug-2018
Language
English
Publication Type
Journal Article
Review
Keywords
Air Pollutants - analysis
Air Pollution - statistics & numerical data
Animals
Arctic Regions
Climate change
Environmental Monitoring - methods
Humans
Ice
Models, Theoretical
Oceans and Seas
Polychlorinated biphenyls - analysis
Rivers - chemistry
Seasons
Soil Pollutants - analysis
Water Pollutants, Chemical - analysis
Abstract
Polychlorinated biphenyls (PCBs) can be used as chemical sentinels for the assessment of anthropogenic influences on Arctic environmental change. We present an overview of studies on PCBs in the Arctic and combine these with the findings from ArcRisk-a major European Union-funded project aimed at examining the effects of climate change on the transport of contaminants to and their behaviour of in the Arctic-to provide a case study on the behaviour and impact of PCBs over time in the Arctic. PCBs in the Arctic have shown declining trends in the environment over the last few decades. Atmospheric long-range transport from secondary and primary sources is the major input of PCBs to the Arctic region. Modelling of the atmospheric PCB composition and behaviour showed some increases in environmental concentrations in a warmer Arctic, but the general decline in PCB levels is still the most prominent feature. 'Within-Arctic' processing of PCBs will be affected by climate change-related processes such as changing wet deposition. These in turn will influence biological exposure and uptake of PCBs. The pan-Arctic rivers draining large Arctic/sub-Arctic catchments provide a significant source of PCBs to the Arctic Ocean, although changes in hydrology/sediment transport combined with a changing marine environment remain areas of uncertainty with regard to PCB fate. Indirect effects of climate change on human exposure, such as a changing diet will influence and possibly reduce PCB exposure for indigenous peoples. Body burdens of PCBs have declined since the 1980s and are predicted to decline further.
PubMed ID
29956262 View in PubMed
Less detail

Polychlorinated biphenyls (PCBs) as sentinels for the elucidation of Arctic environmental change processes: a comprehensive review combined with ArcRisk project results.

https://arctichealth.org/en/permalink/ahliterature292539
Source
Environ Sci Pollut Res Int. 2018 Jun 28; :
Publication Type
Journal Article
Date
Jun-28-2018
Author
Pernilla Carlsson
Knut Breivik
Eva Brorström-Lundén
Ian Cousins
Jesper Christensen
Joan O Grimalt
Crispin Halsall
Roland Kallenborn
Khaled Abass
Gerhard Lammel
John Munthe
Matthew MacLeod
Jon Øyvind Odland
Janet Pawlak
Arja Rautio
Lars-Otto Reiersen
Martin Schlabach
Irene Stemmler
Simon Wilson
Henry Wöhrnschimmel
Author Affiliation
Norwegian Institute for Water Research (NIVA), 0349, Oslo, Norway. pernilla.carlsson@niva.no.
Source
Environ Sci Pollut Res Int. 2018 Jun 28; :
Date
Jun-28-2018
Language
English
Publication Type
Journal Article
Abstract
Polychlorinated biphenyls (PCBs) can be used as chemical sentinels for the assessment of anthropogenic influences on Arctic environmental change. We present an overview of studies on PCBs in the Arctic and combine these with the findings from ArcRisk-a major European Union-funded project aimed at examining the effects of climate change on the transport of contaminants to and their behaviour of in the Arctic-to provide a case study on the behaviour and impact of PCBs over time in the Arctic. PCBs in the Arctic have shown declining trends in the environment over the last few decades. Atmospheric long-range transport from secondary and primary sources is the major input of PCBs to the Arctic region. Modelling of the atmospheric PCB composition and behaviour showed some increases in environmental concentrations in a warmer Arctic, but the general decline in PCB levels is still the most prominent feature. 'Within-Arctic' processing of PCBs will be affected by climate change-related processes such as changing wet deposition. These in turn will influence biological exposure and uptake of PCBs. The pan-Arctic rivers draining large Arctic/sub-Arctic catchments provide a significant source of PCBs to the Arctic Ocean, although changes in hydrology/sediment transport combined with a changing marine environment remain areas of uncertainty with regard to PCB fate. Indirect effects of climate change on human exposure, such as a changing diet will influence and possibly reduce PCB exposure for indigenous peoples. Body burdens of PCBs have declined since the 1980s and are predicted to decline further.
PubMed ID
29956262 View in PubMed
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Statistical analysis of long-term monitoring data for persistent organic pollutants in the atmosphere at 20 monitoring stations broadly indicates declining concentrations.

https://arctichealth.org/en/permalink/ahliterature257067
Source
Environ Sci Technol. 2014 Oct 8;
Publication Type
Article
Date
Oct-8-2014
Author
Deguo Kong
Matthew MacLeod
Hayley Hung
Ian T Cousins
Source
Environ Sci Technol. 2014 Oct 8;
Date
Oct-8-2014
Language
English
Publication Type
Article
Abstract
During recent decades concentrations of persistent organic pollutants (POPs) in the atmosphere have been monitored at multiple stations worldwide. We used three statistical methods to analyse a total of 748 time series of selected POPs in the atmosphere to determine if there are statistically significant reductions in levels of POPs that have had control actions enacted to restrict or eliminate manufacture, use and emissions. Significant decreasing trends were identified in 560 (75%) of the 748 time series collected from the Arctic, North America and Europe, indicating that the atmospheric concentrations of these POPs are generally decreasing, consistent with overall effectiveness of emission control actions. Statistically significant trends in synthetic time series could be reliably identified with the improved Mann-Kendall (iMK) test and the digital filtration (DF) technique in time series longer than 5 years. The temporal trends of new (or emerging) POPs in the atmosphere are often unclear because time series are too short. A statistical detrending method based on the iMK test was not able to identify abrupt changes in the rates of decline of atmospheric POP concentrations encoded into synthetic time series.
PubMed ID
25296171 View in PubMed
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11 records – page 1 of 2.