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AbstractBecause of their usually high molecular weight, polymers are generally considered as being of low environmental concern and are, therefore, exempted from registration and evaluation within REACH. This exemption is currently being reviewed by the European Commission. Against this background, data on the environmental fate and effects of selected water-soluble synthetic organic polymers used in cosmetic products were evaluated. The considered polymers include non-ionic polyethylene glycols (PEGs), anionic homo- and copolymers of acrylic acid (AA-P&CoPs), and cationic polyquaterniums (PQs). The PEGs are more amenable to biodegradation than the AA-P&CoPs and the PQs, which biodegrade slowly. In wastewater treatment plants, sorption and precipitation are expected to lead to an effective removal of the considered polymers from the wastewater. Uptake and bioaccumulation in aquatic organisms are limited by the large molecular size and, for AA-P&CoPs and PQs, the ionic charge of the polymers. In aquatic ecotoxicity tests, the PEGs and the AA-P&CoPs showed generally no to low toxicity. Effects of AA-P&CoPs on algae and crustaceans are attributed to the chelation of cationic nutrients in soft water, with toxicity being mitigated at higher water hardness. Toxicity of the cationic PQs to aquatic organisms ranged from absent to high, depending on the polymer structure, charge density and molecular weight, as well as on the test organism and test conditions. The observed effects most likely result from interactions with the organisms' surfaces. Aquatic toxicity of the PQs is reduced by dissolved organic carbon, suspended solids, sediments minerals, and at higher water hardness, representative of natural conditions. Results from toxicity tests with sediment and soil organisms were only identified for homopolymers of acrylic acid, showing no toxicity. The evaluation of the available ecotoxicity data suggests that test methods may need to be adapted to the respective polymer type, and further standardised to improve reproducibility. Based on the identified data, the considered polymers are likely to be of low environmental concern. However, this conclusion must be seen as preliminary, since environmental concentrations could not be estimated, and further ecotoxicity data are required, e.g., for sediment and soil organisms.

Authorisation of biocidal products in the European Union is a two-stage process, where the biocidal active substances are approved in a first step at the European level, and the biocidal products are authorised in a second step at member state level. If an active substance is designated as Candidate for Substitution (CFS) during this process, a comparative assessment must be carried out for each biocidal product containing this CFS by the competent authority. The aim of the current project was to evaluate the practicability of the existing technical guidance for this procedure by conducting a number of exemplary comparative assessments, and to develop recommendations for improvements. The analysis of the existing guidance revealed that essential concepts are only vaguely defined and would need considerable expert judgement and ad hoc decisions to be applied within a comparative assessment. The here developed recommendations relate to the definition of a product's intended uses, which are subject to a comparative assessment, and the requirement for chemical diversity of active substances in authorised products that currently often leads to a stop of the comparative assessment. Further recommendations relate to the use of risk mitigation measures and various hazard indices for a qualitative comparative assessment, and a standardised process of a quantitative, risk-based comparative assessment using recalculated risk quotients as decisive step. It is acknowledged that particularly the recommendations regarding the risk-based comparison may result in a considerable workload related to the comparative assessment of biocidal products. However, such efforts appear to be a precondition for a sound and defensible comparison of environmental risks. This could not be obtained by comparing risk quotients that were derived using different assumptions for the products within the assessment.

Abfälle aus sog. Spiegeleinträgen müssen je nach Abfallzusammensetzung als gefahrenrelevant oder nicht gefahrenrelevant eingestuft werden. Dabei werden gefahrenrelevante Eigenschaften anhand der Konzentrationen der Abfallinhaltsstoffe oder anhand einer Prüfung ermittelt. Für das Gefährlichkeitsmerkmal HP 14 (ökotoxisch) gibt es auf EU-Ebene keine konkreten Vorgaben für eine Einstufung anhand von Prüfungen (Biotests). In Deutschland wurde 2013 eine Handlungsempfehlung des UBA zur ökotoxikologischen Charakterisierung von Abfällen veröffentlicht. Ziel des vorliegenden Projekts war es, Vorschläge für eine Aktualisierung und Weiterentwicklung dieser Handlungsempfehlung zu erarbeiten. Eine Literaturrecherche wurde durchgeführt, um Biotest-basierte Strategien für die HP 14-Einstufung von Abfällen, Herangehensweisen bei Probenahme, Probenvorbehandlung und Elution sowie relevante öko-toxikologische Testverfahren zu identifizieren. Die in der UBA-Handlungsempfehlung vorgeschlagene Strategie zur HP 14-Einstufung von Spiegeleinträgen wurde überprüft, und erste Vorschläge für eine Aktualisierung und Weiterentwicklung wurden gemacht. Die Teststrategie wurde anschließend anhand der Beprobung, Aufbereitung und ökotoxikologischen Untersuchung von 10 Abfallproben aus Spiegeleinträgen (Filterstaub, Boden und Steine, Shredderleichtfraktionen und Staub) überprüft. Aufbauend auf den Ergebnissen und Erfahrungen und unter Berücksichtigung der Diskussionen mit dem projektbezogenen Begleitkreis wurden die Vorschläge für eine Aktualisierung und Weiterentwicklung der UBA-Handlungsempfehlung weiter ausgearbeitet. Sie betreffen Probenahme, Probenvorbehandlung, Teilung von Proben im Labor, Elution, ökotoxikologische Testung und Mindestanforderungen an Berichte. Außerdem wurden Punkte identifiziert, für die auf regulatorischer Ebene Handlungsbedarf besteht, und es wurden Vorschläge für Anpassungen der Testrichtlinien für die Biotests gemacht.

Waste from so-called mirror entries has to be categorized as hazardous or non-hazardous depending on its composition. Hazard properties (HP) are determined based on concentrations of the waste constituents or testing. For the hazard property HP 14 (ecotoxic), there are no specific requirements at EU level for the classification based on testing (bioassays). In Germany, recommendations for the ecotoxicological characterization of wastes were published by UBA in 2013 The objective of the present project was to develop proposals for updating and further developing the UBA recommendations. A literature search was carried out to identify biotest-based strategies for the HP 14 classification of waste, approaches to sampling, sample pretreatment and elution as well as relevant ecotoxicological test methods. The strategy proposed in the UBA recommendations for HP 14 classification of mirror entries was verified, and initial suggestions were made for its update and further development. The strategy was then reviewed based on sampling, sample preparation and ecotoxicity testing of 10 waste samples from mirror entries (flue-gas dust, soil and stones, fluff-light fractions and dust). Based on the results and experiences and the discussions with the project advisory group, the proposals for updating and further developing the UBA recommendations were further elaborated. They relate to sampling, sample pretreatment, subsampling in the laboratory, elution, ecotoxicity testing, and minimum requirements for reporting. In addition, issues were identified for which there is a need for action at regulatory level and proposals were made for adjustments to the test guidelines for the biotests.

In view of the advanced development of new specific active pharmaceutical ingredients, the question arises as to whether the established standard procedures for the environmental risk assessment in the context of marketing authorization are still sufficient to adequately cover relevant effects on environmental organisms. The focus of this project is on specific test strategies for substances from the group of oncologicals, cardiologicals and statins, as well as their experimental verification in case studies. Studies with aquatic plants in the Lemna sp. Growth Inhibition Test (⁠OECD⁠ 221), the zebrafish embryo toxicity test (OECD 236) amended with sublethal endpoints and the comet assay with environmentally relevant cell types are discussed as possible adaptations, although not all of them proved to be suitable.

The environmental risk assessment (ERA) focusses on individual chemicals, while non-target organisms in the environment are exposed simultaneously to a multitude of substances from various sources. In the aquatic environment, effluents of wastewater treatment plants (WWTPs) represent a key source for co-incidental mixtures of chemicals from various uses. The aim of the present project was to explore the consideration of mixtures of chemicals released via WWTPs in an ERA. Based on a literature survey and own data on human pharmaceuticals and other substances typically present in the effluents of WWTPs, 20 substances were selected. In total, 33 single-substance and 24 mixtures were assessed in chronic toxicity tests with cyanobacteria, green algae, the water plant Lemna minor and the freshwater crustacean Daphnia magna. The results from the mixture tests provided consistent evidence that the aquatic toxicity of mixtures with regard to chronic endpoints can be predicted by the concept of concentration addition (CA) with less than 3-fold deviation. Evidence for synergistic interaction with respect to CA of the two antibiotics sulfamethoxazole and trimethoprim in primary producers was detected, which calls for further investigations. Furthermore, mixture tests demonstrated that the presence of 50% (v:v) WWTP effluent in the test medium did not impact the predictability of mixture toxicity. With regard to mixture concentrations changing during the exposure time, as it is typical for WWTP effluents, the average mixture concentrations appeared to underestimate chronic mixture effects on reproduction of D. magna, while the peak concentrations provided a better estimate. Single-substance risk assessments were compared to risk assessments for selected mixture scenarios based on different approaches. A mixture assessment factor applied in the ERA of single substances and its appropriate size is discussed in view of a prospective consideration of environmental mixtures of unknown composition in the single-substance ERA.

The aim of the present project was to identify the most relevant factors increasing the uncertainty of the environmental risk assessment (ERA) of endocrine active substances as compared to baseline toxicants. The evaluation was supported by data on endocrine effects of six model substances on fish and aquatic invertebrates. Two key factors were identified: (1) The current evaluation of endocrine effects only covers effects on the estrogen / androgen and thyroid axis, while other endocrine modes of action and, especially, effects on invertebrates are insufficiently covered. (2) At present, it is difficult to assess whether the results of tests with few standard test species are protective for all wildlife species. For fish, effect concentrations in species with similar metabolic capacities are often in the same order of magnitude, but larger differences are observed between species that differ in their metabolic capacities. For invertebrates, cross-species extrapolation is far more complex. This is due to the much higher diversity and heterogeneity of invertebrates and the often fragmentary knowledge on endocrine effects and the underlying processes. The uncertainty of the ERA of endocrine active substances is also increased by mixture effects. It may be increased if worst case exposure conditions coincide with sensitive developmental windows. Further factors (e.g. the irreversibility of effects, effects on the reproductive behaviour, and effects with uncertain population relevance and low-dose effects) and the specificity of the identified factors for endocrine active substances are discussed.