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"Bastian, Susanne"
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Ultrafine and Fine Particles and Hospital Admissions in Central Europe. Results from the UFIREG Study
Abstract
Rationale
Evidence of short-term effects of ultrafine particles (UFP) on health is still inconsistent and few multicenter studies have been conducted so far especially in Europe.
Objectives
Within the UFIREG project, we investigated the short-term effects of UFP and fine particulate matter (particulate matter with an aerodynamic diameter less than 2.5 μm [PM2.5]) on daily cause-specific hospital admissions in five Central and Eastern European cities using harmonized protocols for measurements and analyses.
Methods
Daily counts of cause-specific hospital admissions focusing on cardiovascular and respiratory diseases were obtained for Augsburg and Dresden (Germany), 2011–2012; Chernivtsi (Ukraine), 2013 to March 2014; and Ljubljana (Slovenia) and Prague (Czech Republic), 2012–2013. Air pollution and meteorologic data were measured at fixed monitoring sites in all cities. We analyzed city-specific associations using confounder-adjusted Poisson regression models and pooled the city-specific effect estimates using metaanalysis methods.
Measurements and Main Results
A 2,750 particles/cm3 increase (average interquartile range across all cities) in the 6-day average of UFP indicated a delayed and prolonged increase in the pooled relative risk of respiratory hospital admissions (3.4% [95% confidence interval, −1.7 to 8.8%]). We also found increases in the pooled relative risk of cardiovascular (exposure average of lag 2–5, 1.8% [0.1–3.4%]) and respiratory (6-d average exposure, 7.5% [4.9–10.2%]) admissions per 12.4 μg/m3 increase (average interquartile range) in PM2.5.
Conclusions
Our findings indicated delayed and prolonged effects of UFP exposure on respiratory hospital admissions in Central and Eastern Europe. Cardiovascular and respiratory hospital admissions increased in association with an increase in PM2.5. Further multicenter studies are needed using harmonized UFP measurements to draw definite conclusions on health effects of UFP.
Journal Article
Ozone (O 3 ) observations in Saxony, Germany, for 1997–2020: trends, modelling and implications for O 3 control
Given its importance for human health, vegetation and climate, trends in ground-level ozone (O3) concentrations in eastern Germany were systematically analysed using the long-term O3 data from 16 measurement stations. The findings indicate that despite reductions in oxides of nitrogen (NOx= NO + NO2) concentrations across all sites, O3 pollution in Saxony has in fact worsened over the past decade, especially in densely populated urban areas. The strongest O3 trend is observed at a traffic-dominated station, with an annual ozone increase of 1.2 µg m−3 yr−1 (or 3.5 % yr−1), while urban and rural background stations show more moderate rises of, on average, 0.5 µg m−3 yr−1 (or 1.1 % yr−1) over the last decade. To diagnose O3 formation and the controlling effects of NOx and volatile organic compounds (VOCs) over the past decades in this region, for the first time, detailed photochemical box modelling was performed by means of the complex MCM (Master Chemical Mechanism). Analysis of isopleth diagrams for two seasons indicates that O3 formation was predominantly VOC-limited at traffic and urban sites from 2000 to 2019. The observed rise in O3 levels suggests that current efforts to reduce total non-methane volatile organic compound (TNMVOC, including NMVOCs and oxygenated VOCs) emissions and NOx from various sources unfortunately remain insufficient. Based on anthropogenic and biogenic emission data, we recommend that continued NOx abatement and further additional VOC controls, with a focus on solvent use, be implemented in densely populated areas to mitigate O3 pollution in the coming years.
Journal Article
Ozone observations in Saxony, Germany, for 1997-2020: trends, modelling and implications for O.sub.3 control
Given its importance for human health, vegetation and climate, trends in ground-level ozone (O.sub.3) concentrations in eastern Germany were systematically analysed using the long-term O.sub.3 data from 16 measurement stations. The findings indicate that despite reductions in oxides of nitrogen (NO.sub.x = NO + NO.sub.2) concentrations across all sites, O.sub.3 pollution in Saxony has in fact worsened over the past decade, especially in densely populated urban areas. The strongest O.sub.3 trend is observed at a traffic-dominated station, with an annual ozone increase of 1.2 µg m.sup.-3 yr.sup.-1 (or 3.5 % yr.sup.-1 ), while urban and rural background stations show more moderate rises of, on average, 0.5 µg m.sup.-3 yr.sup.-1 (or 1.1 % yr.sup.-1) over the last decade.
Journal Article
Ozone (O3) observations in Saxony, Germany, for 1997–2020: trends, modelling and implications for O3 control
Given its importance for human health, vegetation and climate, trends in ground-level ozone (O3) concentrations in eastern Germany were systematically analysed using the long-term O3 data from 16 measurement stations. The findings indicate that despite reductions in oxides of nitrogen (NOx= NO + NO2) concentrations across all sites, O3 pollution in Saxony has in fact worsened over the past decade, especially in densely populated urban areas. The strongest O3 trend is observed at a traffic-dominated station, with an annual ozone increase of 1.2 µg m−3 yr−1 (or 3.5 % yr−1), while urban and rural background stations show more moderate rises of, on average, 0.5 µg m−3 yr−1 (or 1.1 % yr−1) over the last decade.To diagnose O3 formation and the controlling effects of NOx and volatile organic compounds (VOCs) over the past decades in this region, for the first time, detailed photochemical box modelling was performed by means of the complex MCM (Master Chemical Mechanism). Analysis of isopleth diagrams for two seasons indicates that O3 formation was predominantly VOC-limited at traffic and urban sites from 2000 to 2019. The observed rise in O3 levels suggests that current efforts to reduce total non-methane volatile organic compound (TNMVOC, including NMVOCs and oxygenated VOCs) emissions and NOx from various sources unfortunately remain insufficient. Based on anthropogenic and biogenic emission data, we recommend that continued NOx abatement and further additional VOC controls, with a focus on solvent use, be implemented in densely populated areas to mitigate O3 pollution in the coming years.
Journal Article
Decreasing trends of particle number and black carbon mass concentrations at 16 observational sites in Germany from 2009 to 2018
Anthropogenic emissions are dominant contributors to air pollution. Consequently, mitigation policies have been attempted since the 1990s in Europe to reduce pollution by anthropogenic emissions. To evaluate the effectiveness of these mitigation policies, the German Ultrafine Aerosol Network (GUAN) was established in 2008, focusing on black carbon (BC) and sub-micrometre aerosol particles. In this study, long-term trends of atmospheric particle number concentrations (PNCs) and equivalent BC (eBC) mass concentration over a 10-year period (2009–2018) were determined for 16 GUAN sites ranging from roadside to high Alpine environments. Overall, statistically significant decreasing trends are found for most of these parameters and environments in Germany. The annual relative slope of eBC mass concentration varies between −13.1 % and −1.7 % per year. The slopes of the PNCs vary from −17.2 % to −1.7 %, −7.8 % to −1.1 %, and −11.1 % to −1.2 % per year for 10–30, 30–200, and 200–800 nm size ranges, respectively. The reductions in various anthropogenic emissions are found to be the dominant factors responsible for the decreasing trends of eBC mass concentration and PNCs. The diurnal and seasonal variations in the trends clearly show the effects of the mitigation policies for road transport and residential emissions. The influences of other factors such as air masses, precipitation, and temperature were also examined and found to be less important or negligible. This study proves that a combination of emission mitigation policies can effectively improve the air quality on large spatial scales. It also suggests that a long-term aerosol measurement network at multi-type sites is an efficient and necessary tool for evaluating emission mitigation policies.
Journal Article
Toxicity of Tungsten Carbide and Cobalt-Doped Tungsten Carbide Nanoparticles in Mammalian Cells in vitro
Background: Tungsten carbide nanoparticles are being explored for their use in the manufacture of hard metals. To develop nanoparticles for broad applications, potential risks to human health and the environment should be evaluated and taken into consideration. Objective: We aimed to assess the toxicity of well-characterized tungsten carbide (WC) and cobaltdoped tungsten carbide (WC-Co) nanoparticle suspensions in an array of mammalian cells. Methods: We examined acute toxicity of WC and of WC-Co (10% weight content Co) nanoparticles in different human cell lines (lung, skin, and colon) as well as in rat neuronal and glial cells (i.e., primary neuronal and astroglial cultures and the oligodendrocyte precursor cell line OLN-93). Furthermore, using electron microscopy, we assessed whether nanoparticles can be taken up by living cells. We chose these in vitro systems in order to evaluate for potential toxicity of the nanoparticles in different mammalian organs (i.e., lung, skin, intestine, and brain). Results: Chemical-physical characterization confirmed that WC as well as WC-Co nanoparticles with a mean particle size of 145 nm form stable suspensions in serum-containing cell culture media. WC nanoparticles were not acutely toxic to the studied cell lines. However, cytotoxicity became apparent when particles were doped with Co. The most sensitive were astrocytes and colon epithelial cells. Cytotoxicity of WC-Co nanoparticles was higher than expected based on the ionic Co content of the particles. Analysis by electron microscopy demonstrated presence of WC nanoparticles within mammalian cells. Conclusions: Our findings demonstrate that doping of WC nanoparticles with Co markedly increases their cytotoxic effect and that the presence of WC-Co in particulate form is essential to elicit this combinatorial effect.
Journal Article
Long-term observations of tropospheric particle number size distributions and equivalent black carbon mass concentrations in the German Ultrafine Aerosol Network (GUAN)
The German Ultrafine Aerosol Network (GUAN) is a cooperative atmospheric observation network, which aims at improving the scientific understanding of aerosol-related effects in the troposphere. The network addresses research questions dedicated to both climate- and health-related effects. GUAN's core activity has been the continuous collection of tropospheric particle number size distributions and black carbon mass concentrations at 17 observation sites in Germany. These sites cover various environmental settings including urban traffic, urban background, rural background, and Alpine mountains. In association with partner projects, GUAN has implemented a high degree of harmonisation of instrumentation, operating procedures, and data evaluation procedures. The quality of the measurement data is assured by laboratory intercomparisons as well as on-site comparisons with reference instruments. This paper describes the measurement sites, instrumentation, quality assurance, and data evaluation procedures in the network as well as the EBAS repository, where the data sets can be obtained (doi:10.5072/guan).
Journal Article
Transcriptional inhibition in Schwann cell development and nerve regeneration
Schwann cells, the myelinating glial cells of the peripheral nervous system are remarkably plastic after nerve trauma. Their transdifferentiation into specialized repair cells after injury shares some features with their development from the neural crest. Both processes are governed by a tightly regulated balance between activators and inhibitors to ensure timely lineage progression and allow re-maturation after nerve injury. Functional recovery after injury is very successful in rodents, however, in humans, lack of regeneration after nerve trauma and loss of function as the result of peripheral neuropathies represents a significant problem. Our understanding of the basic molecular machinery underlying Schwann cell maturation and plasticity has made significant progress in recent years and novel players have been discovered. While the transcriptional activators of Schwann cell development and nerve repair have been well defined, the mechanisms counteracting negative regulation of（re-）myelination are less well understood. Recently, transcriptional inhibition has emerged as a new regulatory mechanism in Schwann cell development and nerve repair. This mini-review summarizes some of the regulatory mechanisms controlling both processes and the novel concept of ＂inhibiting the inhibitors＂ in the context of Schwann cell plasticity.
Journal Article
Internalisation of engineered nanoparticles into mammalian cells in vitro: influence of cell type and particle properties
Cellular internalisation of industrial engineered nanoparticles is undesired and a reason for concern. Here we investigated and compared the ability of seven different mammalian cell cultures in vitro to incorporate six kinds of engineered nanoparticles, focussing on the role of cell type and particle properties in particle uptake. Uptake was examined using light and electron microscopy coupled with energy dispersive X-ray spectroscopy (EDX) for particle element identification. Flow cytometry was applied for semi-quantitative analyses of particle uptake and for exploring the influence on uptake by the phagocytosis inhibitor Cytochalasin D (CytoD). All particles studied were found to enter each kind of cultured cells. Yet, particles were never found within cell nuclei. The presence of the respective particles within the cells was confirmed by EDX. Live-cell imaging revealed the time-dependent process of internalisation of technical nanoparticles, which was exemplified by tungsten carbide particle uptake into the human skin cells, HaCaT. Particles were found to co-localise with lysosomal structures within the cells. The incorporated nanoparticles changed the cellular granularity, as measured by flow cytometry, already after 3 h of exposure in a particle specific manner. By correlating particle properties with flow cytometry data, only the primary particle size was found to be a weakly influential property for particle uptake. CytoD, an inhibitor of actin filaments and therewith of phagocytosis, significantly inhibited the internalisation of particle uptake in only two of the seven investigated cell cultures. Our study, therefore, supports the notion that nanoparticles can enter mammalian cells quickly and easily, irrespective of the phagocytic ability of the cells.
Journal Article