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Retrospective analysis of cyclic volatile methylsiloxanes in archived German fish samples covering a period of two decades

Radermacher, Georg; Rüdel, Heinz; Wesch, Charlotte; Böhnhardt, Anna; Koschorreck, Jan Science of The Total Environment 706 (2020), März, 136011; online 9. Dezember 2019 Cyclic volatile methylsiloxanes (cVMS) are widely applied chemicals used as intermediates in the production of silicon polymers or as ingredients in personal care products. cVMS are under scrutiny due to their environmental properties and their potential for long-range atmospheric transport, persistence and food web magnification. In 2018, the cVMS octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6) were identified as Substances of Very High Concern (SVHC) under the European REACH regulation. To obtain current data on the presence of cVMS in German waters, the spatial and temporal occurrence of D4, D5 and D6 in fillets of bream from major rivers archived in the German Environmental Specimen Bank (ESB) was analyzed with a GC-ICP-MS/MS coupling method. The spatial comparison of 17 sites for the year 2017 revealed that highest cVMS burdens occurred in samples from the Saar river (near to the French/German border). cVMS levels in fish from a lake in northern Germany did not exceed the limits of detection. For selected sites, time series covering the period from 1995 to 2017 were investigated. In most years D5 concentrations in fish were clearly higher than the observed D4 and D6 concentrations. Overall maximum D4 and D5 concentrations (about 320 and 7600 ng g−1 wet weight, respectively) were found at one Saar site in 2009. In three of five analyzed time series D5 concentrations peaked 2007–2011. In recent years, cVMS levels in fish decreased at almost all sites. To allow an assessment of the relevance of the detected cVMS fish concentrations these were compared to environmental quality standards (EQS) for D4 and D5 which were recently enacted in the context of the Swedish implementation of the European Water Framework Directive (WFD). The D5 EQS in fish was exceeded at four sites in several years in the investigated period and in the Saar even till 2017. doi: 10.1016/j.scitotenv.2019.136011

Geochemical data on silicon isotope and Ge/Si ratios along a global erodosequence

Abstract

Rheometric data from rotational tests on magnetorheological silicones

Abstract

Best Available Techniques (BAT) reference document for the non-ferrous metals industries

The BAT reference document (BREF) entitled 'Non-Ferrous Metals Industries' forms part of a series presenting the results of an exchange of information between EU Member States, the industries concerned, non-governmental organisations promoting environmental protection, and the Commission, to draw up, review and, where necessary, update BAT reference documents as required by Article 13(1) of the Directive 2010/75/EU on industrial emissions. This document is published by the European Commission pursuant to Article 13(6) of the Directive. This BREF for 'Non-Ferrous Metals Industries' concerns the activities specified in Sections 2 and 6.8 of Annex I to Directive 2010/75/EU, namely: - 2.1: Metal ore (including sulphide ore) roasting or sintering; - 2.5: Processing of non-ferrous metals: (a) production of non-ferrous crude metals from ore, concentrates or secondary raw materials by metallurgical, chemical or electrolytic processes; (b) melting, including the alloyage, of non-ferrous metals, including recovered products and operation of non-ferrous metal foundries, with a melting capacity exceeding 4 tonnes per day for lead and cadmium or 20 tonnes per day for all other metals; - 6.8: Production of carbon (hard-burnt coal) or electrographite by means of incineration or graphitisation. This document also covers: - the production of zinc oxide from fumes during the production of other metals; - the production of nickel compounds from liquors during the production of a metal; - the production of silicon-calcium (CaSi) and silicon (Si) in the same furnace as the production of ferro-silicon; - the production of aluminium oxide from bauxite prior to the production of primary aluminium, where this is an integral part of the production of the metal; - the recycling of aluminium salt slag. Important issues for the implementation of Directive 2010/75/EU in the non-ferrous metals industries are the emissions to air of dust, metals, organic compounds (which can result in the formation of PCDD/F) and sulphur dioxide; diffuse air emissions; emissions to water of metals (e.g. Hg, Cd, Cu, Pb, Zn); resource efficiency; and the prevention of emissions to soil and groundwater. This BREF contains 12 chapters. Chapters 1 and 2 provide general information on the non-ferrous metals industry and on the common industrial processes and techniques used within the whole sector. Chapters 3, 4, 5, 6, 7, 8, 9 and 10 correspond to the following specific production sectors: copper, aluminium, lead and/or tin, zinc and/or cadmium, precious metals, ferro-alloys, nickel and/or cobalt, and carbon and graphite. For each specific production sector, these eight chapters provide information and data concerning the applied processes and techniques; the environmental performance of installations in terms of current emissions, consumption of raw materials, water and energy, and generation of waste; the techniques to prevent or, where this is not practicable, to reduce the environmental impact of operating installations in these sectors that were considered in determining the BAT; and the emerging techniques as defined in Article 3(14) of the Directive. Chapter 11 presents the BAT conclusions as defined in Article 3(12) of the Directive. Chapter 12 is dedicated to concluding remarks and recommendations for future work. Quelle: BAT-Merkblatt JRC 107041

Markt für Mangan

technologyComment of manganese production (RER): The metal is won by electrolysis (25%) and electrothermic processes (75%). ELECTROLYSIS OF AQUEOUS MANGANESE SALTS The production of manganese metal by the electrolysis of aqueous manganese salts requires at first a milling of the manganese ore. Milling increases the active surface and ensures sufficient reactivity in both the reduction and the subsequent leaching steps. After milling the manganese ore is fed to a rotary kiln where the reduction and calcination takes place. This process is carried out at about 850 - 1000 ºC in a reducing atmosphere. As a reducing agent, several carbon sources can be used e.g. anthracite, coal, charcoal and hydrocarbon oil or natural gas. The cal-cined ore needs to be cooled below 100 ºC to avoid a further re-oxidation. The subsequent leaching process is carried out with recycled electrolyte, mainly sulphuric acid. After leaching and filtration the iron content is removed from the solution by oxidative precipitation and the nickel and cobalt are removed by sulphide precipitation. The purified electrolyte is then treated with SO2 in order to ensure plating of γ-Mn during electrolysis. Electrolysis is carried out in diaphragm cells. The cathode is normally made of stainless steel or titanium. For the anode lead-calcium or lead-silver alloy can be used. After an appropriate reaction time the cathodes are removed from the electrolysis bath. The manganese that is deposited on the cathode starter-sheet is stripped off mechanically and then washed and dried. The metal is crushed to produce metal flakes or powder or granulated, depending on the end use. ELECTROTHERMAL DECOMPOSITION OF MANGANESE ORES The electrothermal process is the second important process to produce manganese metal in an industrial scale. The electrothermal process takes place as a multistage process. In the first stage manganese ore is smelted with only a small amount of reductant in order to reduce mostly the iron oxide. This produces a low-grade ferro-manganese and a slag that is rich in Mn-oxide. The slag is then smelted in the second stage with silicon to produce silicomanganese. The molten silicomanganese can be treated with liquid slag from the fist stage to obtain relatively pure manganese metal. For the last step a ladle or shaking ladle can be used. The manganese metal produced by the electrothermal process contains up to 98% of Mn. Overall emissions and waste: Emissions to air consist of dust and fume emissions from smelting, hard metal and carbide production; Other emissions to air are ammonia (NH3), acid fume (HCl), hydrogen fluoride (HF), VOC and heavy metals. Effluents are composed of overflow water from wet scrubbing systems, wastewater from slag and metal granulation, and blow down from cooling water cycles. Waste includes dust, fume, sludge and slag. References: Wellbeloved D. B., Craven P. M. and Waudby J. W. (1997) Manganese and Manganese Alloys. In: Ullmann's encyclopedia of industrial chemistry (ed. Anonymous). 5th edition on CD-ROM Edition. Wiley & Sons, London. IPPC (2001) Integrated Pollution Prevention and Control (IPPC); Reference Document on Best Available Techniques in the Non Ferrous Metals Industries. European Commission. Retrieved from http://www.jrc.es/pub/english.cgi/ 0/733169 technologyComment of manganese production (RoW): The metal is won by electrolysis (assumption: 25%) and electrothermic processes (assumption: 75%). No detailed information available, mainly based on rough estimates. technologyComment of treatment of non-Fe-Co-metals, from used Li-ion battery, hydrometallurgical processing (GLO): The technique SX-EW is used mainly for oxide ores and supergene sulphide ores (i.e. ores not containing iron). It is assumed to be used for the treatment of the non-Fe-Co-metals fraction. The process includes a leaching stage followed by cementation or electro-winning. A general description of the process steps is given below. In the dump leaching step, copper is recovered from large quantities (millions of tonnes) of strip oxide ores with a very low grade. Dilute sulphuric acid is trickled through the material. Once the process starts it continues naturally if water and air are circulated through the heap. The time required is typically measured in years. Sulphur dioxide is emitted during such operations. Soluble copper is then recovered from drainage tunnels and ponds. Copper recovery rates vary from 30% to 70%. Cconsiderable amounts of sulphuric acid and leaching agents emit into water and air. No figures are currently available on the dimension of such emissions. After the solvent-solvent extraction, considerable amounts of leaching residues remain, which consist of undissolved minerals and the remainders of leaching chemicals. In the solution cleaning step occur precipitation of impurities and filtration or selective enrichment of copper by solvent extraction or ion exchange. The solvent extraction process comprises two steps: selective extraction of copper from an aqueous leach solution into an organic phase (extraction circuit) and the re-extraction or stripping of the copper into dilute sulphuric acid to give a solution suitable for electro winning (stripping circuit). In the separation step occurs precipitation of copper metal or copper compounds such as Cu2O, CuS, CuCl, CuI, CuCN, or CuSO4 • 5 H2O (crystallisation) Waste: Like in the pyrometallurgical step, considerable quantities of solid residuals are generated, which are mostly recycled within the process or sent to other specialists to recover any precious metals. Final residues generally comprise hydroxide filter cakes (iron hydroxide, 60% water, cat I industrial waste).

Markt für Silizium, Elektronikqualität

technologyComment of silicon production, electronics grade (DE, RoW): In practice, EG-silicon is a product from complex chemical production plants. The conventional route for production of EG-silicon comprises three process steps: 1) the MG-silicon is converted into a gas, either trichlorosilane (SiHCl3) or silane (SiH4), 2) this gas is purified by means of distillation, 3) silicon in solid form is deposited in a Siemens reactor. Reference: Jungbluth N., Stucki M, and Frischknecht R. (2009) Photovoltaics. In Dones, R. (Ed.) et al., Sachbilanzen von Energiesystemen: Grundlagen für den ökologischen Vergleich von Energiesystemen und den Einbezug von Energiesystemen in Ökobilanzen für die Schweiz. ecoinvent report No. 6-XII, Swiss Centre for Life Cycle Inventories, Dübendorf, CH, 2009.

Passive equilibrium sampling of hydrophobic organic compounds in homogenised fish tissues of low lipid content

Passive equilibrium sampling using polymer samplers in lean tissue is one of the current challenges in assessing bioaccumulation and biomagnification due to the long time needed to reach equilibrium. Despite recent progress achieved by rolling pieces of intact fish fillet with sheets of silicone, there is still a need for a passive sampling method for homogenates that achieves equilibrium before tissue decay starts. In this work, a new approach for relocation of silicone passive samplers in homogenates of lean fish was established for three homogenates with lipid contents varying from 1.2% to 6.1%. Results showed that for 20 model hydrophobic organic compounds with log KOW between 3.9 and 7.8, equilibrium between the silicone and the tissue was achieved in less than 3 days at 4˚C. The concentrations in lipids obtained using passive equilibrium sampling and those from traditional total solvent extraction agreed well, within a factor of 1.3. This new procedure extends the use of passive samplers to homogenised fish tissues of low lipid content, which is highly relevant for environmental studies focused on bioaccumulation of contaminants. © 2018 The Authors. Published by Elsevier Ltd.

Retrospective analysis of cyclic volatile methylsiloxanes in archived German fish samples covering a period of two decades

Cyclic volatile methylsiloxanes (cVMS) are widely applied chemicals used as intermediates in the production of silicon polymers or as ingredients in personal care products. cVMS are under scrutiny due to their environmental properties and their potential for long-range atmospheric transport, persistence and food web magnification. In 2018, the cVMS octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6) were identified as Substances of Very High Concern (SVHC) under the European REACH regulation. To obtain current data on the presence of cVMS in German waters, the spatial and temporal occurrence of D4, D5 and D6 in fillets of bream from major rivers archived in the German Environmental Specimen Bank (ESB) was analyzed with a GC-ICP-MS/MS coupling method. The spatial comparison of 17 sites for the year 2017 revealed that highest cVMS burdens occurred in samples from the Saar river (near to the French/German border). cVMS levels in fish from a lake in northern Germany did not exceed the limits of detection. For selected sites, time series covering the period from 1995 to 2017 were investigated. In most years D5 concentrations in fish were clearly higher than the observed D4 and D6 concentrations. Overall maximum D4 and D5 concentrations (about 320 and 7600 ng gâ Ì1 wet weight, respectively) were found at one Saar site in 2009. In three of five analyzed time series D5 concentrations peaked 2007â€Ì2011. In recent years, cVMS levels in fish decreased at almost all sites. To allow an assessment of the relevance of the detected cVMS fish concentrations these were compared to environmental quality standards (EQS) for D4 and D5 which were recently enacted in the context of the Swedish implementation of the European Water Framework Directive (WFD). The D5 EQS in fish was exceeded at four sites in several years in the investigated period and in the Saar even till 2017.

Bioanalytical and chemical characterization of organic micropollutant mixtures in long-term exposed passive samplers from the Joint Danube Survey 4: Setting a baseline for water quality monitoring

Monitoring methodologies reflecting the long-term quality and contamination of surface waters are needed to obtain a representative picture of pollution and identify risk drivers. This study sets a baseline for characterizing chemical pollution in the Danube River using an innovative approach, combining continuous three-months use of passive sampling technology with comprehensive chemical (747 chemicals) and bioanalytical (seven in vitro bioassays) assessment during the Joint Danube Survey (JDS4). This is one of the world's largest investigative surface-water monitoring efforts in the longest river in the European Union, which water after riverbank filtration is broadly used for drinking water production. Two types of passive samplers, silicone rubber (SR) sheets for hydrophobic compounds and AttractSPETM HLB disks for hydrophilic compounds, were deployed at nine sites for approximately 100 days. The Danube River pollution was dominated by industrial compounds in SR samplers and by industrial compounds together with pharmaceuticals and personal care products in HLB samplers. Comparison of the Estimated Environmental Concentrations with Predicted No-Effect Concentrations revealed that at the studied sites, at least one (SR) and 4-7 (HLB) compound(s) exceeded the risk quotient of 1. We also detected AhR-mediated activity, oxidative stress response, peroxisome proliferator-activated receptor gamma-mediated activity, estrogenic, androgenic, and anti-androgenic activities using in vitro bioassays. A significant portion of the AhR-mediated and estrogenic activities could be explained by detected analytes at several sites, while for the other bioassays and other sites, much of the activity remained unexplained. The effect-based trigger values for estrogenic and anti-androgenic activities were exceeded at some sites. The identified drivers of mixture in vitro effects deserve further attention in ecotoxicological and environmental pollution research. This novel approach using long-term passive sampling provides a representative benchmark of pollution and effect potentials of chemical mixtures for future water quality monitoring of the Danube River and other large water bodies. © 2023 The Author(s).

Landshut Silicon Foundry GmbH (2007 - 2008)

Berichtsjahr: 2008 Adresse: Jenaer Straße 1 84034 Landshut Bundesland: Bayern Flusseinzugsgebiet: Donau Betreiber: Landshut Silicon Foundry GmbH Haupttätigkeit: Oberflächenbehandlung mit organischen Lösungsmitteln >150 kg/h oder >200 t/a

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