Person: Vierke, Lena
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Lena
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Veröffentlichung Ferntransportpotential von Chemikalien - Wie kann diese besorgniserregende Stoffeigenschaft in der PBT-Bewertung unter REACH berücksichtigt werden?(2013) Ackermann, Juliane; Scheringer, Martin; Vierke, LenaVeröffentlichung Fluorchemikalien: Funktionalität und Umweltschutz(2016) Schulte, Christoph; Vierke, LenaDas Beispiel der Per- und Polyfluoralkylchemikalien zeigt, dass Substanzen schaden können, wenn die Entwickler nur auf die nützlichen Eigenschaften schauen und dabei Gefahren übersehen.Quelle: http://onlinelibrary.wiley.comVeröffentlichung Estimation of the Acid Dissociation Constant of Perfluoroalkyl Carboxylic Acids through an Experimental Investigation of their Water-to-Air Transport(2013) Berger, Urs; Cousins, Ian T.; Vierke, LenaThe acid dissociation constants (pKas) of perfluoroalkyl carboxylic acids(PFCAs) have been the subject of discussion in the literature; for example, values from-0.2 to 3.8 have been suggested for perfluorooctanoic acid (PFOA). The dissociatedanionic conjugate bases of PFCAs have negligible air-water partition coefficients (KAWs)and do not volatilize from water. The neutral acids, however, have relatively high KAWsand volatilization from water has been demonstrated. The extent of volatilization ofPFCAs in the environment will depend on the water pH and their pKa. Knowledge ofthe pKas of PFCAs is therefore vital for understanding their environmental transport and fate. We investigated the water-to-airtransfer of PFCAs in a novel experimental setup. We used ~1 ìg L-1 of PFCAs in water (above environmental backgroundconcentrations but below the concentration at which self-association occurs) at different water pH (pH 0.3 to pH 6.9) andsampled the PFCAs volatilized from water during a 2-day experiment. Our results suggest that the pKas of C4-11 PFCAs are <1.6.For PFOA, we derived a pKa of 0.5 from fitting the experimental measurements with a volatilization model. Perfluoroalkanesulfonic acids were not volatilized, suggesting that their pKas are below the investigated pH range (pKa <0.3).
Quelle: http://pubs.acs.org/Veröffentlichung Perfluorierte Carbonsäuren nicht nur Perfluoroctansäure (PFOA) ist besorgniserregend(2013) Staude, Claudia; Vierke, LenaPerfluorierte Carbonsäuren mit einer Kettenlänge von elf bis vierzehn Kohlenstoffatomen (C11-14 perfluoroalkyl carboxylicacids - PFCAs) sind ubiquitär in der Umwelt zu finden. DieKonzentrationen in Biota zeigen einen ansteigenden Trend.Eine Bewertung der Eigenschaften dieser Stoffe nach denKriterien des Annex XIII der europäischen ChemikalienverordnungREACH bestätigt die sehr persistenten und sehrbioakkumulierenden Eigenschaften der C11-14-PFCAs. Deshalbsind C11-14-PFCAs gemäß der REACH-Verordnungbesonders besorgniserregende Stoffe und seit Dezember2012 auf der Kandidatenliste gelistet. Die von diesen Stoffenausgehenden Risiken sind zu minimieren und die Stoffe durchAlternativstoffe oder -technologien zu ersetzen. Quelle: Mitt. Umweltchem. Ökotox, 19(2013)2, S.30Veröffentlichung Short-chain perfluoroalkyl acids: environmental concerns and a regulatory strategy under REACH(2018) Biegel-Engler, Annegret; Fetter, Èva; Brendel, Stephan; Fetter, Éva; Staude, Claudia; Vierke, LenaBackground Short-chain PFASs (per- and polyfluoroalkyl substances) are widely used as alternatives to long-chain PFASs. Long-chain PFASs become gradually regulated under REACH (EC No. 1907/2006) and other international regulations, due to having persistent, bioaccumulative and toxic properties and/or being toxic for reproduction. The increasingly used short-chain PFASs are assumed to have a lower bioaccumulation potential. Nonetheless, they have other properties of concern and are already widely distributed in the environment, also in remote regions. The REACH Regulation does not directly address these emerging properties of concern, complicating the implementation of regulatory measures. Therefore, this study illustrates these environmental concerns and provides a strategy for a regulation of short-chain PFASs within REACH. Results Short-chain PFASs have a high mobility in soil and water, and final degradation products are extremely persistent. This results in a fast distribution to water resources, and consequently, also to a contamination of drinking water resources. Once emitted, short-chain PFASs remain in the environment. A lack of appropriate water treatment technologies results in everlasting background concentrations in the environment, and thus, organisms are permanently and poorly reversibly exposed. Considering such permanent exposure, it is very difficult to estimate long-term adverse effects in organisms. Short-chain PFASs enrich in edible parts of plants and the accumulation in food chains is unknown. Regarding these concerns and uncertainties, especially with respect to the precautionary principle, short-chain PFASs are of equivalent concern to PBT substances. Therefore, they should be identified as substances of very high concern (SVHC) under REACH. The SVHC identification should be followed by a restriction under REACH, which is the most efficient way to minimize the environmental and human exposure of short-chain PFASs in the European Union. Conclusion Due to an increasing use of short-chain PFASs, an effective regulation is urgently needed. The concerns of short-chain PFASs do not match the "classical" concerns as defined under REACH, but are not of minor concern. Therefore, it is of advantage to clearly define the concerns of short-chain PFASs. This might facilitate the following restriction process under REACH. © The Author(s) 2018Veröffentlichung Transport of perfluoroalkyl acids in a water-saturated sediment(2014) Klitzke, Sondra; Möller, Axel; Vierke, LenaThe objective of this work was to provide updated information on the development of the potentialimpact of heavy metal containing batteries on municipal waste and battery recycling processes followingtransposition of the new EU Batteries Directive 2006/66/EC. A representative sample of 146 differenttypes of commercially available dry and button cells as well as lithium-ion accumulators for mobilephones were analysed for their mercury (Hg)-, cadmium (Cd)- and lead (Pb)-contents. The methods usedfor preparing the cells and analysing the heavy metals Hg, Cd, and Pb were either developed during a formerstudy or newly developed. Several batteries contained higher mass fractions of mercury or cadmiumthan the EU limits. Only half of the batteries with mercury and/or lead fractions above the markingthresholds were labelled. Alkaline-manganese mono-cells and Li-ion accumulators, on average, containedthe lowest heavy metal concentrations, while zinc-carbon batteries, on average, contained thehighest levels.
Quelle: ©2013 Elsevier Ltd. All rights reserved