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2021
The effect of the 2018 extreme meteorological conditions in Europe on methane (CH4) emissions is examined using estimates from four atmospheric inversions calculated for the period 2005–2018. For most of Europe, we find no anomaly in 2018 compared to the 2005–2018 mean. However, we find a positive anomaly for the Netherlands in April, which coincided with positive temperature and soil moisture anomalies suggesting an increase in biogenic sources. We also find a negative anomaly for the Netherlands for September–October, which coincided with a negative anomaly in soil moisture, suggesting a decrease in soil sources. In addition, we find a positive anomaly for Serbia in spring, summer and autumn, which coincided with increases in temperature and soil moisture, again suggestive of changes in biogenic sources, and the annual emission for 2018 was 33 ± 38% higher than the 2005–2017 mean. These results indicate that CH4 emissions from areas where the natural source is thought to be relatively small can still vary due to meteorological conditions. At the European scale though, the degree of variability over 2005–2018 was small, and there was negligible impact on the annual CH4 emissions in 2018 despite the extreme meteorological conditions.
This article is part of a discussion meeting issue ‘Rising methane: is warming feeding warming? (part 2)’.
2021
2021
2021
2021
2021
2021
Safety assessment of titanium dioxide (E171) as a food additive
The present opinion deals with an updated safety assessment of the food additive titanium dioxide (E 171) based on new relevant scientific evidence considered by the Panel to be reliable, including data obtained with TiO2 nanoparticles (NPs) and data from an extended one-generation reproductive toxicity (EOGRT) study. Less than 50% of constituent particles by number in E 171 have a minimum external dimension < 100 nm. In addition, the Panel noted that constituent particles < 30 nm amounted to less than 1% of particles by number. The Panel therefore considered that studies with TiO2 NPs < 30 nm were of limited relevance to the safety assessment of E 171. The Panel concluded that although gastrointestinal absorption of TiO2 particles is low, they may accumulate in the body. Studies on general and organ toxicity did not indicate adverse effects with either E 171 up to a dose of 1,000 mg/kg body weight (bw) per day or with TiO2 NPs (> 30 nm) up to the highest dose tested of 100 mg/kg bw per day. No effects on reproductive and developmental toxicity were observed up to a dose of 1,000 mg E 171/kg bw per day, the highest dose tested in the EOGRT study. However, observations of potential immunotoxicity and inflammation with E 171 and potential neurotoxicity with TiO2 NPs, together with the potential induction of aberrant crypt foci with E 171, may indicate adverse effects. With respect to genotoxicity, the Panel concluded that TiO2 particles have the potential to induce DNA strand breaks and chromosomal damage, but not gene mutations. No clear correlation was observed between the physico-chemical properties of TiO2 particles and the outcome of either in vitro or in vivo genotoxicity assays. A concern for genotoxicity of TiO2 particles that may be present in E 171 could therefore not be ruled out. Several modes of action for the genotoxicity may operate in parallel and the relative contributions of different molecular mechanisms elicited by TiO2 particles are not known. There was uncertainty as to whether a threshold mode of action could be assumed. In addition, a cut-off value for TiO2 particle size with respect to genotoxicity could not be identified. No appropriately designed study was available to investigate the potential carcinogenic effects of TiO2 NPs. Based on all the evidence available, a concern for genotoxicity could not be ruled out, and given the many uncertainties, the Panel concluded that E 171 can no longer be considered as safe when used as a food additive.
2021
Atmospheric Supply of Nitrogen, Copper, HCB, BDE-99, SCCP and PFOS to the Baltic Sea in 2019
Norwegian Meteorological Institute
2021
Air Quality Plans and Measures. Analysis of data submitted from 2014 to 2020.
The submitted data were analysed with the aim to provide information to the EEA Member countries that can be used to improve their air quality management practices, and to give feedback on data quality and possible use. Previous studies in the framework of the Air Implementation Pilot (published in 2012 and 2013) made assessments of the measures and management practices but were not successful in defining the measures’ effectiveness, so the present report also looks into what kind of information can be obtained from the data.
In the period 2014 – 2020, 23 EEA member countries submitted at least one air quality plan. Most countries focus their plans on pollutants related to traffic: NO2 and/or PM10. Most measures target exceedances of NO2 (62 %), PM10 (26 %) and PM2.5 (10 %), and measures are reported that target exceedances of standards of benzo(a)pyrene, nickel and lead (all in PM10) as well as SO2. In one case, the measure is related to benzene.
« Traffic » is the main sector leading to exceedances, with 64 % of records, followed by « domestic heating » (14 %), « local industry » (10 %) and “Other” (8 %). The « Other » category when given further information could comprise a variety of sources including meteorology, agricultural residue burning, harbour activity or shipping.
The majority of the exceedances occurred in urban areas (65 %) followed by suburban areas (21 %), while 14 % of the exceedances addressed in the plans occurred in rural areas.
The available data consist of a large number of individual records (ranging from several hundreds to over 20 thousand depending on the reporting element) that in theory can be linked using unique identifiers. However, not all the records can be linked. While the basis for analysis can vary depending on which reporting segments are used, the overall results are consistent across the segments, and provide a very good overview of which air pollution abatement measures are taken by national and local authorities.
ETC/ATNI
2021
Air quality European-wide annual maps based on the Air Quality (AQ) e-Reporting validated (E1a) measurement data, the EMEP modelling data and other supplementary data have been regularly produced, using the Regression – Interpolation – Merging Mapping (RIMM) methodology. However, due to the time schedule of production of the validated AQ measurement and the EMEP modelling data, the RIMM air quality maps of a year Y have typically not been available until May of year Y+2. In this report, we examine the AQ interim mapping, based on the preliminary (E2a) measurement and the CAMS Ensemble Forecast modelling data. Such interim maps could be prepared one year earlier than the validated maps. In order to overcome an obstacle of data gaps of E2a data in several areas, so-called pseudo stations data in areas with no E2a data are estimated, based on regression relation between E2a data from year Y and validated E1a data from year Y-1, together with the ratio of the modelling results from years Y and Y-1. The analysis have been performed for the PM10 annual average, the NO2 annual average and the ozone indicator SOMO35, based on the 2017 data. We evaluate these maps using the validated E1a data. Based on the results, we recommend the regular production of the interim AQ maps for the examined indicators, in addition to the regular AQ maps.
ETC/ATNI
2021
Forskere har funnet ut hvor mye CO2 vi faktisk slipper ut når vi drar på ferie
Norges forskningsråd
2021
The effective enrichment of perfluoroalkyl acids (PFAAs) in sea spray aerosols (SSA) demonstrated in previous laboratory studies suggests that SSA is a potential source of PFAAs to the atmosphere. In order to investigate the influence of SSA on atmospheric PFAAs in the field, 48 h aerosol samples were collected regularly between 2018 and 2020 at two Norwegian coastal locations, Andøya and Birkenes. Significant correlations (p < 0.05) between the SSA tracer ion, Na+, and PFAA concentrations were observed in the samples from both locations, with Pearson’s correlation coefficients (r) between 0.4–0.8. Such significant correlations indicate SSA to be an important source of atmospheric PFAAs to coastal areas. The correlations in the samples from Andøya were observed for more PFAA species and were generally stronger than in the samples from Birkenes, which is located further away from the coast and closer to urban areas than Andøya. Factors such as the origin of the SSA, the distance of the sampling site to open water, and the presence of other PFAA sources (e.g., volatile precursor compounds) can have influence on the contribution of SSA to PFAA in air at the sampling sites and therefore affect the observed correlations between PFAAs and Na+.
2021
Why is the city's responsibility for its air pollution often underestimated? A focus on PM2.5
While the burden caused by air pollution in urban areas is well documented, the origin of this pollution and therefore the responsibility of the urban areas in generating this pollution are still a subject of scientific discussion. Source apportionment represents a useful technique to quantify the city's responsibility, but the approaches and applications are not harmonized and therefore not comparable, resulting in confusing and sometimes contradicting interpretations. In this work, we analyse how different source apportionment approaches apply to the urban scale and how their building elements and parameters are defined and set. We discuss in particular the options available in terms of indicator, receptor, source, and methodology. We show that different choices for these options lead to very large differences in terms of outcome. For the 150 large EU cities selected in our study, different choices made for the indicator, the receptor, and the source each lead to an average difference of a factor of 2 in terms of city contribution. We also show that temporal- and spatial-averaging processes applied to the air quality indicator, especially when diverging source apportionments are aggregated into a single number, lead to the favouring of strategies that target background sources while occulting actions that would be efficient in the city centre. We stress that methodological choices and assumptions most often lead to a systematic and important underestimation of the city's responsibility, with important implications. Indeed, if cities are seen as a minor actor, plans will target the background as a priority at the expense of potentially effective local actions.
2021
American Geophysical Union (AGU)
2021