Background: The NORMAN Association (https://www.norman-network.com/) initiated the NORMAN Suspect List Exchange (NORMAN-SLE; https://www.norman-network.com/nds/SLE/) in 2015, following the NORMAN collaborative trial on non-target screening of environmental water samples by mass spectrometry. Since then, this exchange of information on chemicals that are expected to occur in the environment, along with the accompanying expert knowledge and references, has become a valuable knowledge base for “suspect screening” lists. The NORMAN-SLE now serves as a FAIR (Findable, Accessible, Interoperable, Reusable) chemical information resource worldwide. Results: The NORMAN-SLE contains 99 separate suspect list collections (as of May 2022) from over 70 contributors around the world, totalling over 100,000 unique substances. The substance classes include per- and polyfluoroalkyl substances (PFAS), pharmaceuticals, pesticides, natural toxins, high production volume substances covered under the European REACH regulation (EC: 1272/2008), priority contaminants of emerging concern (CECs) and regulatory lists from NORMAN partners. Several lists focus on transformation products (TPs) and complex features detected in the environment with various levels of provenance and structural information. Each list is available for separate download. The merged, curated collection is also available as the NORMAN Substance Database (NORMAN SusDat). Both the NORMAN-SLE and NORMAN SusDat are integrated within the NORMAN Database System (NDS). The individual NORMAN-SLE lists receive digital object identifiers (DOIs) and traceable versioning via a Zenodo community (https://zenodo.org/communities/norman-sle), with a total of > 40,000 unique views, > 50,000 unique downloads and 40 citations (May 2022). NORMAN-SLE content is progressively integrated into large open chemical databases such as PubChem (https://pubchem.ncbi.nlm.nih.gov/) and the US EPA’s CompTox Chemicals Dashboard (https://comptox.epa.gov/dashboard/), enabling further access to these lists, along with the additional functionality and calculated properties these resources offer. PubChem has also integrated significant annotation content from the NORMAN-SLE, including a classification browser (https://pubchem.ncbi.nlm.nih.gov/classification/#hid=101). Conclusions: The NORMAN-SLE offers a specialized service for hosting suspect screening lists of relevance for the environmental community in an open, FAIR manner that allows integration with other major chemical resources. These efforts foster the exchange of information between scientists and regulators, supporting the paradigm shift to the “one substance, one assessment” approach. New submissions are welcome via the contacts provided on the NORMAN-SLE website (https://www.norman-network.com/nds/SLE/).

Certain persistent and polar substances may pose a hazard to drinking water resources. To foster the knowledge exchange in this field the Working Group Environmental Monitoring of the German Chemical Society (GDCh) Division Environmental Chemistry and Ecotoxicology discussed at their meeting in December 2018 the significance and relevance of persistent, mobile and toxic chemicals (PMT substances) in the environment. Five oral contributions highlighted not only various aspects such as the identification of potential PMT substances based on certain properties and their possible regulation under the European REACH regulation, but also current developments in the analysis of PMT substances and results from environmental monitoring. The data presented prove that many persistent and mobile substances can be detected in surface waters. Once detected, it can be complex and costly to identify sources and reduce inputs, as a case study on 1,4-dioxane in Bavarian surface waters shows. The same applies to the removal of polar substances from raw water for drinking water production. Today, scientific advances in analytical methods make it easier to identify and quantify even very polar substances in water samples. In addition to the targeted analysis of critical chemicals, non-target screening is playing an increasingly important role. This opens up the possibility of detecting substances in water samples that have not previously been investigated in routine monitoring and testing their relevance for humans and the environment. However, the list of potentially occurring PM substances that have not yet been investigated is still very long. Further methodological improvements seem necessary here. In view of the evidence for the presence of PMT substances in the environment (e.g., trifluoroacetic acid and 1,4-dioxane) and the potential risks for drinking water abstraction, it seems important under consideration of the precautionary principle to identify and prioritise relevant REACH-registered substances. The assessment should be based on the intrinsic properties and the emission potential of the compounds. The implementation of a detailed proposal made at European level to regulate PMT and very persistent and very mobile (vPvM) substances in the context of REACH would ensure that chemicals identified as being substances of very high concern according to the PMT and vPvM criteria are subject to authorisation in future.

Bioaccumulation, the accumulation of a chemical in an organism relative to its level in the ambient medium, is of major environmental concern. Thus, monitoring chemical concentrations in biota are widely and increasingly used for assessing the chemical status of aquatic ecosystems. In this paper, various scientific and regulatory aspects of bioaccumulation in aquatic systems and the relevant critical issues are discussed. Monitoring chemical concentrations in biota can be used for compliance checking with regulatory directives, for identification of chemical sources or event-related environmental risk assessment. Assessing bioaccumulation in the field is challenging since many factors have to be considered that can affect the accumulation of a chemical in an organism. Passive sampling can complement biota monitoring since samplers with standardised partition properties can be used over a wide temporal and geographical range. Bioaccumulation is also assessed for regulation of chemicals of environmental concern whereby mainly data from laboratory studies on fish bioaccumulation are used. Field data can, however, provide additional important information for regulators. Strategies for bioaccumulation assessment still need to be harmonised for different regulations and groups of chemicals. To create awareness for critical issues and to mutually benefit from technical expertise and scientific findings, communication between risk assessment and monitoring communities needs to be improved. Scientists can support the establishment of new monitoring programs for bioaccumulation, e.g. in the frame of the amended European Environmental Quality Standard Directive.

The polycyclic musk compounds HHCB (Galaxolide®) and AHTN (Tonalide®) are commonly used as synthetic fragrances in personal care products and household cleaners. These and other synthetic musk fragrances were quantified in different aquatic samples from the German Environmental Specimen Bank (ESB). While HHCB and AHTN were found in almost all samples, most of the other musk fragrances were detected only in a few samples and mostly at lower concentration levels. Blue mussels from the North Sea showed varying levels of 0.5–1.7 ng g⁻¹ ww for HHCB and 0.4–2.5 ng g⁻¹ ww for AHTN (ww, wet weight) in the period from 1986 to 2000, while blue mussels from the Baltic Sea were only slightly contaminated with synthetic musk fragrances. Lipid weight-related concentrations of synthetic musk compounds in blue mussels were higher than in eelpout muscles, bladder wrack and herring gull eggs. In comparison to the marine specimens, muscles of bream from German rivers had higher concentrations of HHCB and AHTN. The ranges of HHCB and AHTN concentrations in bream from the Elbe River were 545–6400 ng g⁻¹ lw and 48–2130 ng g⁻¹ lw, respectively (lw, lipid weight; five sampling sites, period 1993–2003). In the Rhine River, HHCB and AHTN levels of bream muscles were highest at the Iffezheim site (up to 9750 ng g⁻¹ lw HHCB, 1998). Even higher synthetic musk levels were detected in bream from the rivers Saale and Saar. In recent years, levels of both compounds determined in bream from most sampling sites have decreased from maximum values in the 1990s. As the concentrations of AHTN have decreased faster, the ratio of HHCB to AHTN increased from 2–4 in the 1990s to 10–20 in recent years.