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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
2020
This work aimed to identify the major source(s) of faecal pollution impacting Salcott Creek oyster fisheries in the UK through the examination of the sterol profiles. The concentration of the major sewage biomarker, coprostanol, in water overlying the oysters varied between 0.01 µg L−1 and 1.20 µg L−1. The coprostanol/epicoprostanol ratio ranged from 1.32 (September) to 33.25 (February), suggesting that human sewage represents the key input of faecal material into the estuary. However, a correlation between the sterol profile of water above the oysters with that of water that enters from Tiptree Sewage Treatment Works (r = 0.82), and a sample from a site (Quinces Corner) observed to have a high population of Brent geese (r = 0.82), suggests that both sources contribute to the faecal pollution affecting the oysters. In identifying these key faecal inputs, sterol profiling has allowed targeted management practices to be employed to ensure that oyster quality is optimised.
MDPI
2020
Validation of SMILES HCl profiles over a wide range from the stratosphere to the lower thermosphere
Hydrogen chloride (HCl) is the most abundant (more than 95 %) among inorganic chlorine compounds Cly in the upper stratosphere. The HCl molecule is observed to obtain long-term quantitative estimations of the total budget of the stratospheric chlorine compounds. In this study, we provided HCl vertical profiles at altitudes of 16–100 km using the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) from space. The HCl vertical profile from the upper troposphere to the lower thermosphere is reported for the first time from SMILES observations; the data quality is quantified by comparison with other measurements and via theoretical error analysis. We used the SMILES level-2 research product version 3.0.0. The period of the SMILES HCl observation was from 12 October 2009 to 21 April 2010, and the latitude coverage was 40∘ S–65∘ N. The average HCl vertical profile showed an increase with altitude up to the stratopause (∼ 45 km), approximately constant values between the stratopause and the upper mesosphere (∼ 80 km), and a decrease from the mesopause to the lower thermosphere (∼ 100 km). This behavior was observed in all latitude regions and reproduced by the Whole Atmosphere Community Climate Model in the specified dynamics configuration (SD-WACCM). We compared the SMILES HCl vertical profiles in the stratosphere and lower mesosphere with HCl profiles from Microwave Limb Sounder (MLS) on the Aura satellite, as well as from the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) on SCISAT and the TErahertz and submillimeter LImb Sounder (TELIS) (balloon borne). The TELIS observations were performed using the superconductive limb emission technique, as used by SMILES. The globally averaged vertical HCl profiles of SMILES agreed well with those of MLS and ACE-FTS within 0.25 and 0.2 ppbv between 20 and 40 km (within 10 % between 30 and 40 km; there is a larger discrepancy below 30 km), respectively. The SMILES HCl concentration was smaller than those of MLS and ACE-FTS as the altitude increased from 40 km, and the difference was approximately 0.4–0.5 ppbv (12 %–15 %) at 50–60 km. The difference between SMILES and TELIS HCl observations was about 0.3 ppbv in the polar winter region between 20 and 34 km, except near 26 km. SMILES HCl error sources that may cause discrepancies with the other observations are investigated by a theoretical error analysis. We calculated errors caused by the uncertainties of spectroscopic parameters, instrument functions, and atmospheric temperature profiles. The Jacobian for the temperature explains the negative bias of the SMILES HCl concentrations at 50–60 km.
2020
Environmental Contaminants in an Urban Fjord, 2019
This programme, “Environmental Contaminants in an Urban Fjord” has covered sampling and analyses of sediment and organisms in a marine food web of the Inner Oslofjord, in addition to samples of blood and eggs from herring gull. The programme also included inputs of pollutants via surface water (storm water), and effluent water and sludge from a sewage treatment plant. The bioaccumulation potential of the contaminants in the Oslo fjord food web was evaluated. The exposure to/accumulation of the contaminants was also assessed in birds. A vast number of chemical parameters have been quantified, in addition to some biological effect parameters in cod, and the report serves as a status description of the concentrations of these chemicals in different compartments of the Inner Oslofjord marine ecosystem.
Norsk institutt for vannforskning
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
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
2020
Estimation of the temporal profile of an atmospheric release, also called the source term, is an important problem in environmental sciences. The problem can be formalized as a linear inverse problem wherein the unknown source term is optimized to minimize the difference between the measurements and the corresponding model predictions. The problem is typically ill-posed due to low sensor coverage of a release and due to uncertainties, e.g., in measurements or atmospheric transport modeling; hence, all state-of-the-art methods are based on some form of regularization of the problem using additional information. We consider two kinds of additional information: the prior source term, also known as the first guess, and regularization parameters for the shape of the source term. While the first guess is based on information independent of the measurements, such as the physics of the potential release or previous estimations, the regularization parameters are often selected by the designers of the optimization procedure. In this paper, we provide a sensitivity study of two inverse methodologies on the choice of the prior source term and regularization parameters of the methods. The sensitivity is studied in two cases: data from the European Tracer Experiment (ETEX) using FLEXPART v8.1 and the caesium-134 and caesium-137 dataset from the Chernobyl accident using FLEXPART v10.3.
2020
Epigenetics in breast cancer therapy—New strategies and future nanomedicine perspectives
Epigenetic dysregulation has been recognized as a critical factor contributing to the development of resistance against standard chemotherapy and to breast cancer progression via epithelial-to-mesenchymal transition. Although the efficacy of the first-generation epigenetic drugs (epi-drugs) in solid tumor management has been disappointing, there is an increasing body of evidence showing that epigenome modulation, in synergy with other therapeutic approaches, could play an important role in cancer treatment, reversing acquired therapy resistance. However, the epigenetic therapy of solid malignancies is not straightforward. The emergence of nanotechnologies applied to medicine has brought new opportunities to advance the targeted delivery of epi-drugs while improving their stability and solubility, and minimizing off-target effects. Furthermore, the omics technologies, as powerful molecular epidemiology screening tools, enable new diagnostic and prognostic epigenetic biomarker identification, allowing for patient stratification and tailored management. In combination with new-generation epi-drugs, nanomedicine can help to overcome low therapeutic efficacy in treatment-resistant tumors. This review provides an overview of ongoing clinical trials focusing on combination therapies employing epi-drugs for breast cancer treatment and summarizes the latest nano-based targeted delivery approaches for epi-drugs. Moreover, it highlights the current limitations and obstacles associated with applying these experimental strategies in the clinics.
MDPI
2020
Atmospheric inversions have been used for the past two decades to derive large-scale constraints on the sources and sinks of CO2 into the atmosphere. The development of dense in situ surface observation networks, such as ICOS in Europe, enables in theory inversions at a resolution close to the country scale in Europe. This has led to the development of many regional inversion systems capable of assimilating these high-resolution data, in Europe and elsewhere. The EUROCOM (European atmospheric transport inversion comparison) project is a collaboration between seven European research institutes, which aims at producing a collective assessment of the net carbon flux between the terrestrial ecosystems and the atmosphere in Europe for the period 2006–2015. It aims in particular at investigating the capacity of the inversions to deliver consistent flux estimates from the country scale up to the continental scale.
The project participants were provided with a common database of in situ-observed CO2 concentrations (including the observation sites that are now part of the ICOS network) and were tasked with providing their best estimate of the net terrestrial carbon flux for that period, and for a large domain covering the entire European Union. The inversion systems differ by the transport model, the inversion approach, and the choice of observation and prior constraints, enabling us to widely explore the space of uncertainties.
This paper describes the intercomparison protocol and the participating systems, and it presents the first results from a reference set of inversions, at the continental scale and in four large regions. At the continental scale, the regional inversions support the assumption that European ecosystems are a relatively small sink (−0.21±0.2
Pg C yr−1). We find that the convergence of the regional inversions at this scale is not better than that obtained in state-of-the-art global inversions. However, more robust results are obtained for sub-regions within Europe, and in these areas with dense observational coverage, the objective of delivering robust country-scale flux estimates appears achievable in the near future.
2020
2020
Understanding the global distribution of atmospheric black carbon (BC) is essential for unveiling its climatic effect. However, there are still large uncertainties regarding the simulation of BC transport due to inadequate information about the removal process. We accessed the wet removal rate of BC in East Asia based on long-term measurements over the 2010–2016 period at three representative background sites (Baengnyeong and Gosan in South Korea and Noto in Japan). The average wet removal rate, represented by transport efficiency (TE), i.e., the fraction of undeposited BC particles during transport, was estimated to be 0.73 in East Asia from 2010 to 2016. According to the relationship between accumulated precipitation along trajectory and TE, the wet removal efficiency was lower in East and North China but higher in South Korea and Japan, implying the importance of the aging process and frequency of exposure to below- and in-cloud scavenging conditions during air mass transport. Moreover, the wet scavenging in winter and summer showed the highest and lowest efficiency, respectively, although the lowest removal efficiency in summer was primarily associated with a reduced BC aging process because the in-cloud scavenging condition was dominant. The average half-life and e-folding lifetime of BC were 2.8 and 7.1 d, respectively, which is similar to previous studies, but those values differed according to the geographical location and meteorological conditions of each site. Next, by comparing TE from the FLEXible PARTicle (FLEXPART) Lagrangian transport model (version 10.4), we diagnosed the scavenging coefficients (s−1) of the below- and in-cloud scavenging scheme implemented in FLEXPART. The overall median TE from FLEXPART (0.91) was overestimated compared to the measured value, implying the underestimation of wet scavenging coefficients in the model simulation. The median of the measured below-cloud scavenging coefficient showed a lower value than that calculated according to FLEXPART scheme by a factor of 1.7. On the other hand, the overall median of the calculated in-cloud scavenging coefficients from the FLEXPART scheme was highly underestimated by 1 order of magnitude, compared to the measured value. From an analysis of artificial neural networks, the convective available potential energy, which is well known as an indicator of vertical instability, should be considered in the in-cloud scavenging process to improve the representative regional difference in BC wet scavenging over East Asia. For the first time, this study suggests an effective and straightforward evaluation method for wet scavenging schemes (both below and in cloud), by introducing TE along with excluding effects from the inaccurate emission inventories.
2020
Microfibers (MFs) are frequently reported as the most dominant type of microplastic (MP) found in the marine water column and sediments. A major source of MFs is the use and washing of textiles. Although WWTPs can remove up to 98% of MP, estimates suggest billions of MP are still released from a single WWTP annually. Intrinsic properties (polymer type, density, size) will influence environmental degradation, settling times, and ingestion of MFs by marine organisms. Less well understood is the influence of environmental degradation on the fate of MFs. In the current study, we compare the effect of UV exposure on the degradation and fragmentation of polyester (PET), polyamide (nylon; PA), polyacrylonitrile (acrylic; PAN) and wool fibers. Degradation of MFs was conducted in seawater under environmentally relevant exposure conditions using simulated sunlight. PA, PET and wool MFs exhibited changes in surface morphology after just 2 weeks from the start of exposure, followed by fragmentation after
2020
MetVed v.2.0. Improvement and update of the MetVed emission model for residential wood combustion
This report presents the update of the MetVed-model (Grythe et al., 2019). Among the updates are new emission factors and several new species that include climate gases (CO2, CH4 and N2O). There is now a new parameter that describes the emission altitude and a new and improved time variation. Activity data has been updated to the most recent year (2019), which also has required updates to the model and model input variables. The largest update has been the holiday cabin emission module, which is an entirely new addition. Emissions from cabins differ in several ways from residential emissions. The most notable difference is that cabins are spread over more rural areas and are more dispersed than the residential dwellings. The model differentiates alpine and coastal cabins, which is an important distinction as a high density of cabins exists along the coast and they are mainly used during summer.
NILU
2020
2020