Person: Hellack, Bryan
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Veröffentlichung Aerosol pollution maps and trends over Germany with hourly data at four rural background stations from 2009 to 2018(2020) Heintzenberg, Jost; Birmili, Wolfram; Hellack, BryanA total of 10 years of hourly aerosol and gas data at four rural German stations have been combined with hourly back trajectories to the stations and inventories of the European Emissions Database for Global Atmospheric Research (EDGAR), yielding pollution maps over Germany of PM10, particle number concentrations, and equivalent black carbon (eBC). The maps reflect aerosol emissions modified with atmospheric processes during transport between sources and receptor sites. Compared to emission maps, strong western European emission centers do not dominate the downwind concentrations because their emissions are reduced by atmospheric processes on the way to the receptor area. PM10, eBC, and to some extent also particle number concentrations are rather controlled by emissions from southeastern Europe from which pollution transport often occurs under drier conditions. Newly formed particles are found in air masses from a broad sector reaching from southern Germany to western Europe, which we explain with gaseous particle precursors coming with little wet scavenging from this region. Annual emissions for 2009 of PM10, BC, SO2, and NOx were accumulated along each trajectory and compared with the corresponding measured time series. The agreement of each pair of time series was optimized by varying monthly factors and annual factors on the 2009 emissions. This approach yielded broader summer emission minima than published values that were partly displaced from the midsummer positions. The validity of connecting the ambient concentration and emission of particulate pollution was tested by calculating temporal changes in eBC for subsets of back trajectories passing over two separate prominent emission regions, region A to the northwest and B to the southeast of the measuring stations. Consistent with reported emission data the calculated emission decreases over region A are significantly stronger than over region B. © Author(s) 2020.Veröffentlichung Closing gaps for environmental risk screening of engineered nanomaterials(2019) Kühnel, Dana; Hellack, Bryan; Nickel, Carmen; Kussatz, Carola; Zalm, Esther van der; Zalm, Esther van derEngineered nanomaterials (ENM) have a widespread presence in human life and are components of many products and applications. This warrants an easy and fast evaluation of potential environmental risks. However, so far this is hampered by the multitude of different nanomaterials on the markets in addition to the many variations in form, size and surface modifications. Testing of each variation of ENM is not manageable, and hence the development and application of fast risk screening tools for ENMs is discussed. Here, we present the development of a scoring scheme with regard to ENM environmental risks under consideration of the two compartments water and soil. It allows for the ranking of ENM according to their environmental fate and hazard by taking into account criteria that are meaningful and relevant for ENM. The selection of the criteria is based on conceptual considerations, existing knowledge, and experimental work including transport and transformation studies as well as aquatic and terrestrial toxicity tests. The allocation of the ENM to the scores informs on the potential for transport and transformation and the hazard potential. Fate and hazard scores are subsequently combined into one risk score (1â€Ì10 for aquatic compartment, 1â€Ì7 for terrestrial compartment). The risk score has the intention to indicate which ENM may need prioritization for further action, i.e. with regard to the degree of detail for further testing or modelling. The applicability and consistency of the scoring schemes were assessed by taking different chemical species (e.g. of Ag, TiO2, SiO2, Cu, Fe) of ENM in various modifications (e.g. different shapes and coatings) into account. In conclusion, the established scoring schemes were found to be applicable to rank ENM according to their environmental fate and hazard potential, and thus to their environmental risk potential. © 2019 The Authors. Published by Elsevier B.V.