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AbstractSynthetic polymers are chemicals of emerging concern for the environment, which is mainly attributed to their persistence in environmental compartments. On the other hand, polymers exist in nature as well. They are regarded of no concern for the environment. The present article focusses on the environmental fate of natural polymers and the implications on the persistence assessment for synthetic polymers. Natural polymers vary widely in structure, function, and properties. Crystallinity, wettability and surface area are important influencing factors on the (bio)degradation kinetics. Chemical and enzymatic hydrolysis is the most important process for the degradation of natural polymers, which for particulate material takes place either by bulk or surface erosion. Some natural polymers are degraded rapidly, but in other cases, degradation of natural polymers takes very long until complete mineralization. These differences in biodegradability are a result of evolution as they have to fulfil specific functions in nature which might require a certain persistency. Consequently, many natural polymers would have to be considered persistent or very persistent (P or vP) based on the available studies using the standard assessment approach. At the same time, they are considered no concern to the environment for good reasons. The analysis emphasizes that mineralization alone is not a resilient persistence endpoint for polymers. This needs to be recognized when assessing synthetic polymers, many of which would fulfil the existing P/vP criteria as well. For such synthetic polymers, it would be important to establish meaningful endpoints and polymer specific criteria to enable an adequate persistence assessment using a weight-of-evidence approach.

AbstractBackgroundOECD TG 309 "Aerobic Mineralisation in Surface Water" (OECD Test Guideline 309 (2004)) is currently used in regulation for the assessment of the persistence of chemicals in surface water. The test is performed in a batch under defined conditions. Processes which might be relevant for the fate of a chemical in surface water like direct and indirect photolysis are not addressed. In order to study the impact of sunlight on the fate in surface water, pendimethalin, a herbicidal active substance with known sensitivity to aqueous photolysis, was used. This was tested in an experiment based on OECD 309, but scaled up to 900 L size with a 1.40 m water column and irradiated with special lamps in order to monitor the fate of the substance at different water depths, in comparison to dark controls.ResultsPendimethalin degraded significantly under the applied test conditions. The test setups with exposure to simulated sunlight showed a significant faster degradation compared to the dark experiments. Application of 900 g sediment (1% of test system) to the test system further increased the degradation rate. In the simulated sunlight setups a faster degradation was observed in the upper water layer, hence, the concentration of the photolysis products were highest in the upper water layer, where the highest light intensity was measured. With decreasing light intensity in deeper water layers photolysis products were still detected at a water depth of 125 cm. Mineralisation up to 22% of the applied radioactivity was observed. In the dark controls neither significant amounts of photolysis products nor any mineralisation were detected. Among the different sampling depths no significant differences were observed. It was further observed that the dark controls became anaerobic at the end of the incubation time. This has been observed previously in standard laboratory tests according to OECD 309.ConclusionsThe study proves that for a substance sensitive to photolysis like pendimethalin, exposure to simulated sunlight leads to a significantly reduced degradation half-life (DegT50) in surface water compared to the dark control. In the standard test according to OECD guideline 309 the influence of photolytical degradation is not considered and thus the laboratory test can lead to the overestimation of the persistence of a chemical in surface water and consequently to a false-positive evaluation in the overall PBT assessment (ECHA Guidance on Information Requirements and Chemical Safety Assessment 2004), when only the results of the standard OECD 309 study are considered.

Abstract
A continuous task of the working group "Environmental Monitoring" is the development of methods and guidelines for a systematic and long-term analytical control of the chemical burden of environmental compartments and biota A new recommendation regarding the substance-related environmental monitoring is published in "Environmental Science and Pollution Research" (Rüdel et al., 2009). The "Chemical and Biological Monitoring Series", published in the same journal, originates from the working group or from its individual members also. Some central points of these articles are picked up and updated in this report. Current topics of major concern are the transformation of pharmaceuticals and its consequences for environmental monitoring and the monitoring of biocides and nanoparticles.
Besides other objectives the working group "Soil Chemistry and Soil Ecology" focuses on the development and standardisation of methods for the chemical, physical, and biological characterisation of soil pollution by specific contaminants as well as on the elaboration of methods for the assessment of potential harmful effects on soil, soil ecology, and on other potentially targeted environmental media. Recently the working group has summarized its main outcomes and conclusions in the position paper "Target Orientated Exposition Estimation in Soil Assessment" which is part of this report. Furthermore several other initiatives and activities of the working group are presented.

Abstract
Background
Persistence is a key criterion for the risk assessment of chemicals. In degradation tests, microbial biodegradation of labeled test chemicals leads to the incorporation of the label in microbial biomass, resulting in biogenic non-extractable residues (bioNER), which are not considered as harmful in persistence assessment. The amount of bioNER can be estimated using the microbial turnover to biomass (MTB) model. MTB estimates the biomass growth during productive degradation of a compound from theoretical growth yield and CO2-formation and gives an upper and a lower value for bioNER formation. The aim of this study is use available experimental data for bioNER to assess the validity, accuracy and precision of the MTB method as new tool in persistence assessment.

Results
We collected experimental data in order to test accuracy and precision of this estimation method. In total, 16 experimental studies were found in literature where bioNER was experimentally quantified. Hereof, 13 studies used the amount of label recovered from total amino acid (tAA) content as proxy for bioNER. Unfortunately, the comparison with experimental data was difficult due to the variety of employed methods. A conversion factor is required to extrapolate from tAA on bioNER, and this factor may vary during the experiment and between experiments. The bioNER formation for all compounds tested was calculated with the MTB method, and the outcome was compared to measured tAA as proxy for bioNER. The relation between predicted and measured bioNER was significant, but no better correlation was obtained than with CO2 to tAA. The mean absolute error of the prediction (low MTB versus tAA) was 5% applied label (range 0.3 to 16%). Some deviation between measured results and calculated bioNER could be contributed to uncertainties in the experimental determination, as shown by variance in replicates (bromoxynil) or high background of label in sterile samples (sulfadiazine).

Conclusions
MTB thus provides a robust model for determining of the potential amounts of biomass and bioNER formed from the degradation of organic chemicals.

Abstract
Background
Discussion concerning the bioavailability and ecotoxicological relevance of non-extractable residues (NER) in soil is still ongoing. Is NER formation a detoxification process or a hidden hazard? The use of radiolabelled chemicals enables detection of NER, but the identity of NER is usually unknown. Regulations require clear measurable parameters and the approach of Ortega-Calvo et al. (Environ Sci Technol 49:10255–10264, 2015) defines these.

Results
Following that approach, we studied the fate of three ecotoxic, NER-forming chemicals over a period of 6 months after application to three different soils. Initial 14C experiments showed formation of NER for all chemicals. For the chemical 2,4,6-trinitrotoluene (TNT), NER-formation was reproducible in all soils. We applied a recently standardized method using Tenax® to remove the bioavailable fraction of the chemical at test start and test end. Removing the bioavailable fractions also removed toxicity. Further experiments without radiolabelled TNT clearly showed that the toxicity measured in applied soils was caused by the bioavailable chemical and not by NER.

Conclusions
The tool developed can be used if the fate of the chemical including NER formation is well known and reproducible. The other selected chemicals, cypermethrin and carbendazim, showed unexpected behaviour in 14C-fate experiments. The degree of biodegradation was not reproducible for cypermethrin and unexpected losses occurred with carbendazim. This indicated a very large uncertainty when using non-radiolabelled compounds in NER experiments and thus the tool is not suitable in non-radiolabelled experiments.

Abstract
Background
Spreading of manure on agricultural soils represents an important pathway by which veterinary medicinal and biocidal products enter the environment. To assess their environmental impact in the context of authorization processes, experimental testing of transformation of these compounds in manure is considered in regulatory guidance documents. However, there is no standardized experimental test method available so far. To fill this gap, an experimental test method was developed to examine transformation in liquid cattle and pig manure.

Results
To account for manure specifics and for a possible influence of manure parameters on transformation rates, a comprehensive data acquisition and statistical analysis were performed. To address the variability of liquid manure of different type and origin, 30 manures were sampled and characterized. Thereof, three cattle and three pig manures were selected to perform anaerobic transformation studies with two radiolabeled veterinary medicinal active substances (14C-salicylic acid and 14C-paracetamol) and a confidential radiolabeled "14C-biocide B" serving as test compounds. Spatial and seasonal variability of manure parameters was quantified, and a sampling technique to obtain homogenous manure samples was developed. Transformation studies with six replicates per sampling point were conducted to examine the influence of test setup, of manure storage conditions, and of parameter variations between manure of the same species and of different species on half-lives, formation of extractable and non-extractable residues and mineralization rates. Finally, a test design was established that yields reproducible results for transformation studies in liquid cattle and pig manure under anaerobic conditions.

Conclusions
Results give a reliable basis for an experimental test method to perform anaerobic transformation studies in liquid cattle and pig manure. The developed test method comprises detailed guidance on selection of sampling date and site, collection from manure tank, storage duration and temperature in the laboratory, duration of manure acclimation period, and the incubation system design. It proved to give reproducible results in a validation ring test performed in a follow-up project and is planned to be submitted as draft test guideline for approval by the OECD.

Erste wissenschaftliche Studien zum Verbleib von technischem Nanomaterial (ENM) in Abfallverbrennungsanlagen [BÖR16, LAN16, WAL12, BAR16] deuten darauf hin, dass der Großteil der verwendeten ENM in den festen Verbrennungsrückständen verbleibt, wobei es möglicherweise nicht dauerhaft in diesen gebunden wird [WAL12]. Dementsprechend verlagert sich der Fokus der Untersuchungen hin zu nachgelagerten Schritten in der Verwertung bzw. Entsorgung der nanomaterialhaltigen mineralischen Rückstände aus der Verbrennung. Dies wurde zum Anlass genommen, um im Rahmen des zweijährigen UFOPLAN-Vorhabens "Untersuchungen zur möglichen Freisetzung von Nanopartikeln bei der Ablagerung und bodenbezogenen Anwendung von mineralischen Abfällen" mögliche Emissionspfade für aus der Hausmüll- bzw. Klärschlammverbrennung stammende Nanopartikel mithilfe von Laborversuchen zu untersuchen. Als ENM wurde nanoskaliges Titandioxid (nTiO2) in Form des Produkts Hombikat UV 100 WP der Fa. Venator eingesetzt. Nach der Herstellung ENM-haltiger HMV-Schlacken und Klärschlammaschen in großtechnischen Abfallbehandlungsanlagen, wurden diese in Laborversuchen hinsichtlich ihres Staubungs- und Elutionsverhaltens untersucht. Bei den Staubungsversuchen wurde bei Proben mit geringem Wasseranteil Titan sowohl bei den untersuchten HMV-Schlacken als auch bei den Klärschlammaschen in der alveolengängigen, der thorakalen und der einatembaren Fraktion des Staubs in höherer Konzentration als bei der Referenz detektiert. Bei den nassen Schlacken - welche typischerweise den Verhältnissen in der Praxis entsprechen - konnte Titan nur im thorakalen Staub gegenüber der Referenzprobe nachgewiesen werden. Neben den Staubungsversuchen wurden auch Elutionsversuche durchgeführt. In den Untersuchungen konnte gezeigt werden, dass standardisierte Labor-Elutionsverfahren in der Lage sind, im Vergleich mit Kontrollmaterialien erhöhte Mobilität von nTiO2 sicher anzuzeigen. Die beobachtete erhöhte Mobilität im Laborversuch konnten in Simulationsversuchen im Technikumsmaßstab bestätigt werden. Dort, wo die Elutionsversuche keine erhöhte Mobilität anzeigte, trat sie auch im Simulationsversuch nicht auf.

Parasiticides are veterinary pharmaceuticals very frequently used in pasture animals. Particularly substances of the classes of avermectins and milbemycins are very common. These substances are highly toxic to non-target organisms, often stable in the environment (persistent) and may potentially accumulative in organisms. The present project contributes to filling environmental data gaps for avermectins and milbemycins. In addition, risk management strategies for parasiticides used in pasture animals were evaluated with regard to their efficacy and practicability reducing the risk to dung or soil organisms.