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The Norwegian Arctic possesses a unique environment for the detection of new potential chemicals of emerging Arctic concern (CEACs) due to remoteness, sparse population and the low number of local contamination sources. Hence, a contaminant present in Arctic air is still considered a priority indication for its environmental stability and environmental mobility. Today, legacy persistent organic pollutants (POPs) and related conventional environmental pollutants are already well-studied because of their identification as Arctic pollutants in the 1980s. Many of them are implemented and reported in various national and international monitoring activities including the Arctic Monitoring and Assessment Programme (AMAP). These standard monitoring schemes, however, are based on compound-specific quantitative analytical methods. Under such conditions, the possibility for the identification of hitherto unidentified contaminants is limited and random at best. Today, new and advanced technological developments allow a broader, unspecific analytical approach as either targeted multicomponent analysis or suspect and non-target screening strategies. In order to facilitate such a wide range of compounds, a wide-scope sample clean-up method for high-volume air samples based on a combination of adsorbents was applied, followed by comprehensive two-dimensional gas chromatography separation and low-resolution time-of-flight mass spectrometric detection (GC × GC-LRMS). During the study reported here, simultaneous non-target and suspect screening were applied. The detection of over 700 compounds of interest in the particle phase and over 1200 compounds in the gaseous phase is reported. Of those, 62 compounds were confirmed with reference standards and 90 compounds with a probable structure (based upon mass spectrometric interpretation and library spectrum comparison). These included compounds already detected in Arctic matrices and compounds not detected previously (see also Fig. 1). In addition, 241 compounds were assigned a tentative structure or compound class. Hitherto unknown halogenated compounds, which are not listed in the mass spectral libraries used, were also detected and partly identified.
2020
Impact of late spring Siberian snow on summer rainfall in South-Central China
Located in the Yangtze River Valley and surrounded by mountains, South-Central China (SCC) frequently suffered from natural disasters such as torrential precipitation, landslide and debris flow. Here we provide corroborative evidence for a link between the late spring (May) snow water equivalent (SWE) over Siberia and the summer (July–August, abbr. JA) rainfall in SCC. We show that, in May, anomalously low SWE over Siberia is robustly related to a large warming from the surface to the mid-troposphere, and to a stationary Rossby wave train from Siberia eastward toward the North Atlantic. On the one hand, over the North Atlantic there exhibits a tripole pattern response of sea surface temperature anomalies in May. It persists to some extent in JA and in turn triggers a wave train propagating downstream across Eurasia and along the Asian jet, as the so-called Silk Road pattern (SRP). On the other hand, over northern Siberia the drier soil occurs in JA, accompanied by an overlying anomalous anticyclone through the positive feedback. This anomalous anticyclone favors the tropospheric cooling over southern Siberia, and the meridional (northward) displacement of the Asian jet (JMD) due to the change in the meridional temperature gradient. The combination of the SRP and the JMD facilitates less water vapor transport from the tropical oceans and anomalous descending motion over SCC, and thus suppresses the precipitation. These findings indicate that May Siberian SWE can be exploited for seasonal predictability of SCC precipitation.
2020
Hepato(Geno)Toxicity Assessment of Nanoparticles in a HepG2 Liver Spheroid Model
(1) In compliance with the 3Rs policy to reduce, refine and replace animal experiments, the development of advanced in vitro models is needed for nanotoxicity assessment. Cells cultivated in 3D resemble organ structures better than 2D cultures. This study aims to compare cytotoxic and genotoxic responses induced by titanium dioxide (TiO2), silver (Ag) and zinc oxide (ZnO) nanoparticles (NPs) in 2D monolayer and 3D spheroid cultures of HepG2 human liver cells. (2) NPs were characterized by electron microscopy, dynamic light scattering, laser Doppler anemometry, UV-vis spectroscopy and mass spectrometry. Cytotoxicity was investigated by the alamarBlue assay and confocal microscopy in HepG2 monolayer and spheroid cultures after 24 h of NP exposure. DNA damage (strand breaks and oxidized base lesions) was measured by the comet assay. (3) Ag-NPs were aggregated at 24 h, and a substantial part of the ZnO-NPs was dissolved in culture medium. Ag-NPs induced stronger cytotoxicity in 2D cultures (EC50 3.8 µg/cm2) than in 3D cultures (EC50 > 30 µg/cm2), and ZnO-NPs induced cytotoxicity to a similar extent in both models (EC50 10.1–16.2 µg/cm2). Ag- and ZnO-NPs showed a concentration-dependent genotoxic effect, but the effect was not statistically significant. TiO2-NPs showed no toxicity (EC50 > 75 µg/cm2). (4) This study shows that the HepG2 spheroid model is a promising advanced in vitro model for toxicity assessment of NPs.
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Review on the methodology supporting the health impact assessment by the European Environment Agency
2020
Estimation of pollutant releases into the atmosphere is an important problem in the environmental sciences. It is typically formalized as an inverse problem using a linear model that can explain observable quantities (e.g., concentrations or deposition values) as a product of the source-receptor sensitivity (SRS) matrix obtained from an atmospheric transport model multiplied by the unknown source-term vector. Since this problem is typically ill-posed, current state-of-the-art methods are based on regularization of the problem and solution of a formulated optimization problem. This procedure depends on manual settings of uncertainties that are often very poorly quantified, effectively making them tuning parameters. We formulate a probabilistic model, that has the same maximum likelihood solution as the conventional method using pre-specified uncertainties. Replacement of the maximum likelihood solution by full Bayesian estimation also allows estimation of all tuning parameters from the measurements. The estimation procedure is based on the variational Bayes approximation which is evaluated by an iterative algorithm. The resulting method is thus very similar to the conventional approach, but with the possibility to also estimate all tuning parameters from the observations. The proposed algorithm is tested and compared with the standard methods on data from the European Tracer Experiment (ETEX) where advantages of the new method are demonstrated. A MATLAB implementation of the proposed algorithm is available for download.
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Microplastic (MP) is of growing concern to environmental and human health. This study investigated three analytical approaches to measure MP in tissues of salmonids. The study aimed to 1) determine and demonstrate the sensitivity of current analytical methods for MP in salmon tissues for the three different quantitative methods, 2) compare the utility of the different methods in terms of cost, time and sensitivity 3) quantify MP in a relevant selection of tissues of farmed and wild salmon in order to establish likely indicator organs for future documentation purposes. We here present the results, compare the methods and discuss uncertainties and needs for further method development.
NORCE Research AS
2020
På oppdrag fra Elkem Carbon AS, har NILU utført målinger av arsen (As) i omgivelsene til Elkem Carbon i Vågsbygd
(Kristiansand kommune). Bedriften ble pålagt av Miljødirektoratet å gjennomføre As-målinger i omgivelsesluft. PM10-prøver tatt med filterprøvetaker i boligområdet på Fiskåtangen (Konsul Wilds vei) ble analysert med hensyn på As med induktivt koblet plasma massespektrometri (ICP-MS). Rapporten dekker målinger i perioden 25. september 2019 – 28. september 2020. Årsmiddelverdien av konsentrasjonen av As ble målt til 2,38 ng/m3. Målsettingsverdien for tiltak i forurensningsforskriften på 6 ng/m3 ble overholdt med god margin. Årsmiddelverdien var marginalt lavere enn nedre vurderingsterskel på 2,4 ng/m3. Et langtransportert bidrag til de to høyeste registrerte As døgnkonsentrasjonene kan ikke utelukkes.
NILU
2020
Environmental pollutants in the terrestrial and urban environment 2019
Samples from the urban terrestrial environment in the Oslo area were analysed for various inorganic and organic environmental pollutants. The selected species were earthworm, fieldfare, sparrowhawk, brown rat, red fox and tawny owl. Air- and soil-samples were also included in the study to further the understanding on sources and uptake of pollutants. A foodchain approach was used to investigate trophic magnification of the different compounds.
NILU
2020
Grenseområdene Norge-Russland. Luft- og nedbørkvalitet, årsrapport 2019.
Smelteverkene i nordvest-Russland slipper ut store mengder svoveldioksid (SO2) og tungmetaller. Utslippene påvirker luft- og nedbørkvalitet i grenseområdene. Miljøovervåkingen viser at grenseverdier for SO2 er overholdt i kalenderåret 2019, samt for vinter 2018/19. I januar 2019 var det to episoder med høye konsentrasjoner av SO2 på Svanvik. 25. januar ble det sendt varsel til befolkningen i området. Målsettingsverdier for Ni og As er overholdt.
NILU
2020
The paper provides the annual update of the European air quality concentration maps and population exposure estimates for human health related indicators of pollutants PM10 (annual average, 90.4 percentile of daily means), PM2.5 (annual average), ozone (93.2 percentile of maximum daily 8-hour means, SOMO35, SOMO10) and NO2 (annual average), and vegetation related ozone indicators (AOT40 for vegetation and for forests) for the year 2017. The report contains also NOx annual average concentration map for 2017. The trends in exposure estimates in the period 2005-2017 for PM10 and ozone, resp. in the period 2007-2017 for PM2.5 are summarized. The analysis is based on interpolation of annual statistics of the 2017 observational data reported by EEA Member countries in 2016 and stored in the Air Quality e-reporting database. The mapping method is the Regression – Interpolation – Merging Mapping. It combines monitoring data, chemical transport model results and other supplementary data using linear regression model followed by kriging of its residuals (residual kriging). The paper presents the mapping results and gives an uncertainty analysis of the interpolated maps.
ETC/ATNI
2020
This program, «Monitoring of environmental contaminants in freshwater ecosystems and single species in large Norwegian lakes”, has covered sampling and determination of environmental contaminants by analyses of organisms in an aquatic, pelagic food web of Lake Mjøsa, and in the top predator in Lake Femunden. Samples of different trophic levels, from epipelagic zooplankton to the top predator brown trout, were collected during the late stages of the growth season in 2019. In this report, the status of contamination in the food web, trends and biomagnification potential of various environmental contaminants is discussed.
Norsk institutt for vannforskning (NIVA)
2020
Monitoring of the atmospheric ozone layer and natural ultraviolet radiation. Annual Report 2019.
This report summarizes the results from the Norwegian monitoring programme on stratospheric ozone and UV radiation
measurements. The ozone layer has been measured at three locations since 1979: In Oslo/Kjeller, Tromsø/Andøya and
Ny-Ålesund. The UV measurements started in 1995. The results show that there was a significant decrease in stratospheric
ozone above Norway between 1979 and 1997. After that, the ozone layer stabilized at a level ~2% below pre-1980 level.
2019 was characterized by low ozone values in April and an “ozone hole” in Southern Norway in December 2019.
NILU
2020