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We employ JRA-55 (Japanese 55-year Reanalysis), a recent second-generation global reanalysis providing data of high quality in the stratosphere, to examine whether a distinguishable effect of geomagnetic activity on Northern Hemisphere stratospheric temperatures can be detected. We focus on how the statistical significance of stratospheric temperature differences may be robustly assessed during years with high and low geomagnetic activity. Two problems must be overcome. The first is the temporal autocorrelation of the data, which is addressed with a correction of the t statistics by means of the estimate of the number of independent values in the series of correlated values. The second is the problem of multiplicity due to strong spatial autocorrelations, which is addressed by means of a false discovery rate (FDR) procedure. We find that the statistical tests fail to formally reject the null hypothesis, i.e. no significant response to geomagnetic activity can be found in the seasonal-mean Northern Hemisphere stratospheric temperature record.
2020
Risk governance of emerging technologies demonstrated in terms of its applicability to nanomaterials
Nanotechnologies have reached maturity and market penetration that require nano‐specific changes in legislation and harmonization among legislation domains, such as the amendments to REACH for nanomaterials (NMs) which came into force in 2020. Thus, an assessment of the components and regulatory boundaries of NMs risk governance is timely, alongside related methods and tools, as part of the global efforts to optimise nanosafety and integrate it into product design processes, via Safe(r)‐by‐Design (SbD) concepts. This paper provides an overview of the state‐of‐the‐art regarding risk governance of NMs and lays out the theoretical basis for the development and implementation of an effective, trustworthy and transparent risk governance framework for NMs. The proposed framework enables continuous integration of the evolving state of the science, leverages best practice from contiguous disciplines and facilitates responsive re‐thinking of nanosafety governance to meet future needs. To achieve and operationalise such framework, a science‐based Risk Governance Council (RGC) for NMs is being developed. The framework will provide a toolkit for independent NMs' risk governance and integrates needs and views of stakeholders. An extension of this framework to relevant advanced materials and emerging technologies is also envisaged, in view of future foundations of risk research in Europe and globally.
2020
Determining the Bio‐Based Carbon Content of Surfactants
In response to a mandate from the European Commission, the European Committee for Standardization (CEN) called on the technical committee CEN/TC 276 to develop a European standard (EN 17035) to define bio‐based surfactants and enable quantification of the bio‐based carbon content of surfactants based on radiocarbon analyses. This analytical approach was tested through directly contracted analyses and through a round robin procedure at commercial facilities in Europe. Initial results were unsatisfactory and further investigation identified issues surrounding the degree of homogenization in the samples. In general, the samples were only homogeneous at the gram level while the maximum quantity of material that could be introduced to the analytical process was at the milligram level. Having identified the root cause of the discrepancies between measured and expected results, new samples were sent to six European laboratories. The results were satisfactory indicating linearity and accuracy across the measurement range.
2020
The white-tailed eagle (Haliaeetus albicilla) in Scandinavia has suffered from impaired reproduction due to high exposure to industrial pollution between the 1960s and 1980s. While population numbers are rising again, new contaminants, such as per- and polyfluoroalkyl substances (PFAS), are increasingly found in high trophic avifauna and are of concern to potentially impact once again on population health. In the present study, we examined PFAS levels in plasma of white-tailed eagle nestlings from northern Norway over the last decade (2008–2017). While PFOA and PFNA exposure did not follow a significant time trend, PFOS and PFHxS concentrations decreased over time, and ≥C11 perfluorinated carboxylic acids only seem to level off during the last four years. This may in fact be the first evidence for a change in the trend for some of these compounds. Furthermore, since several PFAS are expected to be highly present in aqueous film-forming foams used at airports, we also investigate the potential of the two main airports in the region to act as hotspots for PFAS. Our results indeed show decreasing exposure to PFOA with distance to the airports. Altogether, our results seem to show that legislation actions are effective, and continued concern for PFAS exposure of high trophic wildlife is still warranted, even in the northern environment.
2020
Air quality in Europe - 2020 report
The Air quality in Europe report provides an annual assessment of the status and impacts of air quality and recent air quality trends. The report supports policy development and implementation in the field of air quality at both European and national levels.
European Environment Agency
2020
2020
2020
2020
2020
On the robustness of field calibration for smart air quality monitors
The robustness of field calibrated Air Quality Multi-sensors (AQM) performances to long term and/or mobile operation is still debated. Though accuracy generally exceeds the one of laboratory calibrations models, experimental results show that field calibration models cannot sustain optimal field performances due to changes occurring in operative conditions. Among them, the relocation of calibrated multi-sensors platforms and sensor drift are considered as the most relevant. In this work, we want to provide an answer to the general issue of field calibration robustness assessement. Analysing theoretical foundations and providing tools for determining the calibration model validity domain. In particular, by leveraging the probability distribution of target and interferent gas as well as environmental variables, measures of dissimilarity between calibration and operative phase conditions are considered to quantitatively capture the occurring change. A 6 months multiple nodes dataset including node relocations events in several sites have been processed for deriving nonlinear multivariate field calibrations whose robustness to changing conditions have been analysed. Kullback-Leibler, Euclidean and Hellinger dissimilarity measurements have been correlated with recorded performance degradation. Results show that quantifying relevant factors probability distribution changes allows to explain and predict performances of in field data driven calibration models. They also highlight the role of concept drift in explaining field performances ameliorating our capability to select optimal conditions in which a field calibration should be derived. Finally, smart air quality monitors could now autonomously detect the need for re-calibration.
2020
The quality and relevance of nanosafety studies constitute major challenges to ensure their key role as a supporting tool in sustainable innovation, and subsequent competitive economic advantage. However, the number of apparently contradictory and inconclusive research results has increased in the past few years, indicating the need to introduce harmonized protocols and good practices in the nanosafety research community. Therefore, we aimed to evaluate if best-practice training and inter-laboratory comparison (ILC) of performance of the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay for the cytotoxicity assessment of nanomaterials among 15 European laboratories can improve quality in nanosafety testing. We used two well-described model nanoparticles, 40-nm carboxylated polystyrene (PS-COOH) and 50-nm amino-modified polystyrene (PS-NH2). We followed a tiered approach using well-developed standard operating procedures (SOPs) and sharing the same cells, serum and nanoparticles. We started with determination of the cell growth rate (tier 1), followed by a method transfer phase, in which all laboratories performed the first ILC on the MTS assay (tier 2). Based on the outcome of tier 2 and a survey of laboratory practices, specific training was organized, and the MTS assay SOP was refined. This led to largely improved intra- and inter-laboratory reproducibility in tier 3. In addition, we confirmed that PS-COOH and PS-NH2 are suitable negative and positive control nanoparticles, respectively, to evaluate impact of nanomaterials on cell viability using the MTS assay. Overall, we have demonstrated that the tiered process followed here, with the use of SOPs and representative control nanomaterials, is necessary and makes it possible to achieve good inter-laboratory reproducibility, and therefore high-quality nanotoxicological data.
2020
2020
In this report, we investigate the relative expanded uncertainty (REU) formula for comparing low-cost sensors (microsensors) and reference measurements. The purpose of the REU formula is to check if microsensor measurements follow the data quality objective (DQO) of the European Air Quality Directive 2008/50/EC to be considered equivalent to a reference instrument. The project aimed to obtain a good understanding of the REU formula for its proper use in current and future projects involving microsensors.
NILU
2020
2020
FLEXPART v10.1 simulation of source contributions to Arctic black carbon
The Arctic environment is undergoing rapid changes such as faster warming than the global average and exceptional melting of glaciers in Greenland. Black carbon (BC) particles, which are a short-lived climate pollutant, are one cause of Arctic warming and glacier melting. However, the sources of BC particles are still uncertain. We simulated the potential emission sensitivity of atmospheric BC present over the Arctic (north of 66∘ N) using the FLEXPART (FLEXible PARTicle) Lagrangian transport model (version 10.1). This version includes a new aerosol wet removal scheme, which better represents particle-scavenging processes than older versions did. Arctic BC at the surface (0–500 m) and high altitudes (4750–5250 m) is sensitive to emissions in high latitude (north of 60∘ N) and mid-latitude (30–60∘ N) regions, respectively. Geospatial sources of Arctic BC were quantified, with a focus on emissions from anthropogenic activities (including domestic biofuel burning) and open biomass burning (including agricultural burning in the open field) in 2010. We found that anthropogenic sources contributed 82 % and 83 % of annual Arctic BC at the surface and high altitudes, respectively. Arctic surface BC comes predominantly from anthropogenic emissions in Russia (56 %), with gas flaring from the Yamalo-Nenets Autonomous Okrug and Komi Republic being the main source (31 % of Arctic surface BC). These results highlight the need for regulations to control BC emissions from gas flaring to mitigate the rapid changes in the Arctic environment. In summer, combined open biomass burning in Siberia, Alaska, and Canada contributes 56 %–85 % (75 % on average) and 40 %–72 % (57 %) of Arctic BC at the surface and high altitudes, respectively. A large fraction (40 %) of BC in the Arctic at high altitudes comes from anthropogenic emissions in East Asia, which suggests that the rapidly growing economies of developing countries could have a non-negligible effect on the Arctic. To our knowledge, this is the first year-round evaluation of Arctic BC sources that has been performed using the new wet deposition scheme in FLEXPART. The study provides a scientific basis for actions to mitigate the rapidly changing Arctic environment.
2020