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Concentrations of organohalogenated contaminants (OHCs) can show significant temporal and spatial variation in the environment and wildlife. Most of the variation is due to changes in use and production, but environmental and biological factors may also contribute to the variation. Nestlings of top predators are exposed to maternally transferred OHCs in the egg and through their dietary intake after hatching. The present study investigated spatial and temporal variation of OHCs and the role of age and diet on these variations in plasma of Norwegian white-tailed eagle (Haliaeetus albicilla) nestlings. The nestlings were sampled at two locations, Smøla and Steigen, in 2015 and 2016. The age of the nestlings was recorded (range: 44 - 87 days old) and stable carbon and nitrogen isotopes (δ13C and δ15N) were applied as dietary proxies for carbon source and trophic position, respectively. In total, 14 polychlorinated biphenyls (PCBs, range: 0.82 - 59.05 ng/mL), 7 organochlorinated pesticides (OCPs, range: 0.89 - 52.19 ng/mL), 5 polybrominated diphenyl ethers (PBDEs, range: 0.03 - 2.64 ng/mL) and 8 perfluoroalkyl substances (PFASs, range: 4.58 - 52.94 ng/mL) were quantified in plasma samples from each location and year. The OHC concentrations, age and dietary proxies displayed temporal and spatial variations. The age of the nestlings was indicated as the most important predictor for OHC variation as the models displayed significantly decreasing plasma concentrations of PCBs, OCPs, and PBDEs with increasing age, while concentrations of PFASs were significantly increasing with age. Together with age, the variations in PCB, OCP and PBDE concentrations were also explained by δ13C and indicated decreasing concentrations with a more marine diet. Our findings emphasise age and diet as important factors to consider when investigating variations in plasma OHC concentrations in nestlings.
2018
Water column distribution of mercury species in permanently stratified aqueous environments
Biogeochemical structures of three permanently stratified waterbodies were studied: a sea water basin (the Black Sea), an estuary (Hunnbunn fjord), and a freshwater lake (Nordbytjernet), with focus on the distributions of methylmercury (MeHg) and total mercury (THg). THg concentrations were similar in the sea water basin (0.2–1.8 ng/L) and the freshwater lake (0.8–1.2 ng/L), but significantly higher in the estuary (0.6–9.4 ng/L). An increase in the MeHg concentration and MeHg/THg ratio were found in the redox zone in all three basins, indicating bacterial production of MeHg in the aqueous phase. In the lake and estuary, the maximum MeHg concentration and MeHg/THg ratio were found in samples located closest to the bottom sediments, likely due to the formation of MeHg in surface sediments and subsequent diffusion to the overlying waters.
2018
2018
The Zeppelin Observatory is an atmospheric monitoring station located on the northwest coast of Spitzbergen island, in the Svalbard archipelago. The station provides background air composition, meteorological and climatological data for numerous research projects. The observatory is located on a mountain ridge in a region with complex topography that affects local atmospheric circulation processes. Research question: How the seasonal data collected at the Zeppelin observatory and Ny-Ålesund station (Fig. 2b), a temporarily station in the settlement, is affected by: 1) micrometeorological conditions 2) mesoscale dynamics 3) local air pollution
2018
In this study we apply two methods for data collection that are relatively new in the field of atmospheric science. The two developed methods are designed to collect essential geo-localized information to be used as input data for a high resolution emission inventory for residential wood combustion (RWC). The first method is a webcrawler that extracts openly online available real estate data in a systematic way, and thereafter structures them for analysis. The webcrawler reads online Norwegian real estate advertisements and it collects the geo-position of the dwellings. Dwellings are classified according to the type (e.g., apartment, detached house) they belong to and the heating systems they are equipped with. The second method is a model trained for image recognition and classification based on machine learning techniques. The images from the real estate advertisements are collected and processed to identify wood burning installations, which are automatically classified according to the three classes used in official statistics, i.e., open fireplaces, stoves produced before 1998 and stoves produced after 1998. The model recognizes and classifies the wood appliances with a precision of 81%, 85% and 91% for open fireplaces, old stoves and new stoves, respectively. Emission factors are heavily dependent on technology and this information is therefore essential for determining accurate emissions. The collected data are compared with existing information from the statistical register at county and national level in Norway. The comparison shows good agreement for the proportion of residential heating systems between the webcrawled data and the official statistics. The high resolution and level of detail of the extracted data show the value of open data to improve emission inventories. With the increased amount and availability of data, the techniques presented here add significant value to emission accuracy and potential applications should also be considered across all emission sectors.
2018
Altitude-temporal behaviour of atmospheric ozone, temperature and wind velocity observed at Svalbard
2018
2018
2018
2018
Model development for high-resolution emissions from residential wood combustion
In this report, we describe the MetVed model developed to estimate emissions from residential wood combustion (RWC) at high spatial-temporal resolution. The model uses a downscaling method approach, which builds on bottom-up principles and derive a wood burning potential for each grid based on the housing type, size and heating technology, energy demand and outdoor temperature of each grid. The model builds on the combination of several databases with information at high level of detail. The databases contain geo-localised information about dwelling number and type, energy consumption statistics, fireplace and stove locations, and the available technology for residential heating. The datasets are combined and the dependencies between the different variables are analysed. MetVed includes the time variation for RWC based on the heating degree concept combined with time-variation from consumer statistics, and the vertical distribution based on the RWC shared in apartment buildings versus houses. The results from the MetVed-model have shown to improve the accuracy of dispersion modelling results when compared with predictions based on previous emission inventories.
NILU
2018
2018
Maternal-Child Exposures to Persistent Organic Pollutants in Dhaka, Bangladesh
Information about the human burdens of persistent organic pollutants (POPs) in low- and middle-income countries is limited. In particular, studies often include only a small subset of POPs. To address this data gap, we aimed to assess maternal-child exposures to POPs in Dhaka, Bangladesh. We quantified 16 organochlorine pesticides, 12 polychlorinated biphenyls, 21 brominated flame retardants, 18 per- and polyfluorinated alkyl substances, 2 polycyclic aromatic hydrocarbons, and short-chain chlorinated paraffins in 18 pooled samples of human cord blood from 90 mother–infant pairs living in Dhaka, Bangladesh (2014–2015). In all pooled samples, we detected high levels of p,p′-DDT (median 81.6 ng/g lipid) and its metabolites p,p′-DDE and p,p′-DDD (median 551 and 10.7 ng/g lipid, respectively), where the p,p′-DDE/p,p′-DDT ratio ranged from 2.9 to 9.8 indicating recent dichlorodiphenyltrichloroethane (DDT) exposure. We also detected acenaphthene, decabromodiphenyl ethane, o,p′-DDT, o,p′-DDE, hexachlorobenzene, β-hexachlorocyclohexane, hexabromobenzene, and perfluorooctanoic acid in a subset of samples. For the other 59 target compounds, concentrations were below the limits of detection, despite using ultra-trace analytical methodology. No trends were observed when stratifying the analyses of detected POP concentrations by maternal age, maternal body mass index, or large fish consumption. These findings highlight recent DDT exposure in Dhaka, but the overall POP burden was otherwise low in this sample of pregnant women/newborns. Future monitoring efforts should focus on newly detected POPs for which burdens may be increasing due to ongoing industrialization in Bangladesh.
2018
Understanding the bioaccumulation mechanisms of per- and polyfluoroalkyl substances (PFASs) across different chain-lengths, isomers and functional groups represents a monumental scientific challenge with implications for chemical regulation. Here, we investigate how the differential tissue distribution and bioaccumulation behavior of 25 PFASs in crucian carp from two field sites impacted by point sources can provide information about the processes governing uptake, distribution and elimination of PFASs. Median tissue/blood ratios (TBRs) were consistently <1 for all PFASs and tissues except bile which displayed a distinct distribution pattern and enrichment of several perfluoroalkyl sulfonic acids. Transformation of concentration data into relative body burdens (RBBs) demonstrated that blood, gonads, and muscle together accounted for >90% of the amount of PFASs in the organism. Principal component analyses of TBRs and RBBs showed that the functional group was a relatively more important predictor of internal distribution than chain-length for PFASs. Whole body bioaccumulation factors (BAFs) for short-chain PFASs deviated from the positive relationship with hydrophobicity observed for longer-chain homologues. Overall, our results suggest that TBR, RBB, and BAF patterns were most consistent with protein binding mechanisms although partitioning to phospholipids may contribute to the accumulation of long-chain PFASs in specific tissues.
2018