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Survey of mercury, cadmium and lead content of household batteries
(2014) Recknagel, Sebastian; Radant, Hendrik; Kohlmeyer, Regina
The 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: Waste Management 34 (2014) 156-161
Transport of perfluoroalkyl acids in a water-saturated sediment
(2014) Klitzke, Sondra; Möller, Axel; Vierke, Lena
The 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
Aus alten Rohren
(2013)
Leitungen aus Blei vergiften noch immer in tausenden Haushalten das Trinkwasser. Das Schwermetall schädigt vor allem Schwangere und Kleinkinder. Zum Schutz sinkt ab dem 1. Dezember der erlaubte Bleigehalt von 25 auf 10 Mikrogramm je Liter. Letzte Bleirohre müssen dann endgültig raus. Die Stiftung Warentest beantwortet die wichtigsten Fragen: Wie viele giftige Rohre gibt es noch? Wie erfahre ich, ob ich betroffen bin? Wer führt Wasseranalysen durch? Wer zahlt für die neue Leitung? Eine Grafik zeigt, wo in Deutschland das Risiko am größten ist.
© www.test.de
Evaluation of field-scale variability of heavy metal sorption in soils by scale factors
(2015) Xiao, Han; Böttcher, Jürgen; Utermann, Jens
The ability of soils to sorb heavy metals is quantified by sorption isotherms. The field-scale variability of heavy metal sorption isotherms across fields of apparently "homogeneousŁ soil is often very large and makes the upscaling of point measurements to larger scales problematic. This may be overcome by scaling of sorption isotherms, which is a method that potentially reduces the wide spread of the isotherms into a reference or average isotherm, respectively, but preserves the variation through calculated scale factors. At two study sites near Hannover, Germany (loess soil at Lathwehren, loamy to sandy soil at Vinnhorst), we investigated the field-scale variability of the sorption isotherms of cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn). For each site, 50 samples were taken along a 250 m transect at two depths. Further, for each site and depth a composite sample was mixed from aliquots of the 50 transect samples. Sorption isotherms of single heavy metals were measured, along with a range of soil properties, including pH, CEC, OC, and texture. The isotherms were successfully parameterized by the Freundlich equation and were spatially very variable. Calculation of scale factors for the sorption isotherms was successful, as scaling reduction of variance was high (from 64% to 99%). We then tested if correlations between scale factors of different heavy metal sorption isotherms, and also to soil properties existed. Such correlation were expected, because heavy metals (e.g. Cd and Zn) are competitively adsorbed, and the respective soil properties directly relate to ion sorption in soil. Significant correlations between scale factors of heavy metal sorption isotherms were only found at one site and depth (in the loamy to sandy subsoil). Thus, these relationships were site- and depth specific and are not generalizable. In addition, significant correlations between scale factors of heavy metal sorption isotherms and soil properties occurred only sporadically, and were not transferrable. One possible reason for this might be that the data were transformed (difference transformation) prior to correlation analysis to obtain normality. A further objective was to prove, whether the average isotherms can be represented by a single measured isotherms of the composite samples from the area. This was found to hold at the loess site, but not at the loamy to sandy site. This indicates that scaling is favorable to sites not too much differing in soil texture. Although correlation analysis revealed only sporadic and not transferrable correlations, a multiple linear regression equation for the Lathwehren subsoil was found to predict Cu sorption scale factors from organic carbon content and cation exchange capacity. From our investigation we conclude that scaling is a useful tool to quantify and express field-scale variability of heavy metal sorption isotherms in soils. However, a prediction of scale factors from simple soil properties was only partly successful and needs further research efforts.Quelle: Verlagsinformation

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