Updated consumer risk assessment of fluoride in food and drinking water including the contribution from other sources of oral exposure.

This updated risk assessment evaluated evidence on potential adverse health effects of fluoride related to all sources of oral exposure as mandated by the European Commission. Fluoride benefit assessment was not included. Effects on the central nervous system, thyroid and bone were prioritised.

INSIGHT: An integrated framework for safe and sustainable chemical and material assessment.

The assessment of chemicals and materials has traditionally been fragmented, with health, environmental, social, and economic impacts evaluated independently. This disjointed approach limits the ability to capture trade-offs and synergies necessary for comprehensive decision-making under the Safe and Sustainable by Design (SSbD) framework. The EU INSIGHT project addresses this challenge by developing a novel computational framework for integrated impact assessment, based on the Impact Outcome Pathway (IOP) approach.

Developmental neurotoxicity (DNT): A call for implementation of new approach methodologies for regulatory purposes: Summary of the 5th International Conference on DNT Testing.

The 5th International Conference on Developmental Neurotoxicity (DNT) Testing (DNT5) took place in April 2024 in Konstanz, Germany, organized by CAAT-Europe, the University of Konstanz, and scientists from the US EPA, SCAHT, and CAAT at Johns Hopkins University Bloomberg School of Public Health. The conference convened experts from regulatory agencies, industry, and academia to explore the latest advancements in DNT testing and the integration of animal-free new approach methodologies (NAMs) into next-generation risk assessment (NGRA). The key topic was the appli-cation and further development of the recently established DNT in vitro test battery (DNT-IVB).

Statement concerning the review of the approval of the basic substances chitosan and chitosan hydrochloride when used in plant protection.

The European Commission asked EFSA to provide an opinion according to Article 23(6) of Regulation (EC) No 1107/2009, in conjunction with Article 29 of Regulation (EC) No 178/2002, regarding the approved plant protection uses of chitosan and chitosan hydrochloride as basic substances. The Panel on Plant Protection Products and their Residues (PPR) was not provided with new dossiers but collated available scientific and technical knowledge and used a weight of evidence approach and experts' judgement for its appraisal. The statement has considered the possibility for extrapolation of the toxicological properties between chitosan and chitosan hydrochloride, and whether both substances can be expected to be of no toxicological concern; a comparison between the estimated levels of chitosan and chitosan hydrochloride resulting from the approved uses as basic substances and the level of chitosan expected to naturally occur in the environment.

Daphnids can safeguard the use of alternative bioassays to the acute fish toxicity test: a focus on neurotoxicity.

Assessment of potential impacts of chemicals on the environment traditionally involves regulatory standard data requirements for acute aquatic toxicity testing using algae, daphnids, and fish (e.g., Organisation for Economic Co-operation and Development [OECD] test guidelines 201, 202, and 203, respectively), representing different trophic levels.

Easy-MODA: Simplifying standardised registration of scientific simulation workflows through MODA template guidelines powered by the Enalos Cloud Platform.

Modelling Data (MODA) reporting guidelines have been proposed for common terminology and for recording metadata for physics-based materials modelling and simulations in a CEN Workshop Agreement (CWA 17284:2018). Their purpose is similar to that of the Quantitative Structure-Activity Relationship (QSAR) model report form (QMRF) that aims to increase industry and regulatory confidence in QSAR models, but for a wider range of model types. Recently, the WorldFAIR project's nanomaterials case study suggested that both QMRF and MODA templates are an important means to enhance compliance of nanoinformatics models, and their underpinning datasets, with the FAIR principles (Findable, Accessible, Interoperable, Reusable).

A developmental neurotoxicity adverse outcome pathway (DNT-AOP) with voltage gate sodium channel (VGSC) inhibition as a molecular initiating event (MiE).

The adverse outcome pathway (AOP) framework serves as a practical tool for organising scientific knowledge that can be used to infer cause-effect relationships between stressor events and toxicity outcomes in intact organisms. However, a major challenge in the broader application of the AOP concept within regulatory toxicology is the development of a robust AOPs that can withstand peer review and acceptance. This is mainly due to the considerable amount of work required to substantiate the modular units of a complete AOP, which can take years from inception to completion.

In vitro evaluation of the carcinogenic potential of perfluorinated chemicals.

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are the major components of long-chain per- and polyfluorinated alkyl substances (PFAS), known for their chemical stability and environmental persistence. Even if PFOA and PFOS have been phased out or are limited in use, they still represent a concern for human and environmental health. Several studies have been per­formed to highlight the toxicological behavior of these chemicals and their mode of action (MoA).

Pollutant exposure and myocardial injury: Protocol and progress report for a toxicological systematic mapping review.

An increasing body of evidence identifies pollutant exposure as a risk factor for cardiovascular disease (CVD), while CVD incidence is rising steadily with the aging population. Although numerous experimental studies are now available, the mechanisms through which lifetime exposure to envi­ronmental pollutants can result in CVD are not fully understood. To comprehensively describe and understand the pathways through which pollutant exposure leads to cardiotoxicity, a systematic mapping review of the available toxicological evidence is needed.

Linking nanomaterial-induced mitochondrial dysfunction to existing adverse outcome pathways for chemicals.

The adverse outcome pathway (AOP) framework plays a crucial role in the paradigm shift of tox­icity testing towards the development and use of new approach methodologies. AOPs developed for chemicals are in theory applicable to nanomaterials (NMs). However, only initial efforts have been made to integrate information on NM-induced toxicity into existing AOPs.

A Human Cell-based Assay to Assess the Induction of Vasculature Formation for Non-genotoxic Carcinogenicity Testing Purposes: A Pilot Study.

The induction of vasculature formation is proposed to be a significant mechanism behind the non-genotoxic carcinogenicity of a chemical. The vasculature formation model used in this study is based on the coculture of human primary HUVECs and hASCs. This model was used to develop an assay to assess the induction of vasculature formation.

The Cell Transformation Assay: A Historical Assessment of Current Knowledge of Applications in an Integrated Approach to Testing and Assessment for Non-Genotoxic Carcinogens.

The history of the development of the cell transformation assays (CTAs) is described, providing an overview of in vitro cell transformation from its origin to the new transcriptomic-based CTAs. Application of this knowledge is utilized to address how the different types of CTAs, variously addressing initiation and promotion, can be included on a mechanistic basis within the integrated approach to testing and assessment (IATA) for non-genotoxic carcinogens. Building upon assay assessments targeting the key events in the IATA, we identify how the different CTA models can appropriately fit, following preceding steps in the IATA.

OECD workshop consensus report: Ethical considerations with respect to human derived products, specifically human serum, in OECD test guidelines.

The ethical needs and concerns with use and sourcing of human materials, particularly serum, in OECD test guidelines were explored in a dedicated international workshop held in 2019. The health-related aspects of the donation procedure, including tissue screening, donor health, laboratory work health protection, permission from the donor for commercial use, payment of the donors and the potential for exploitation of low-income populations and data protection of the donors; supply, availability, and competition with clinical needs; traceability of the serum and auditability/GLP needs for the Test Guideline Programme, were examined. Here we provide the recommendations of the workshop with respect to the use of human serum, and potentially other human reagents, specifically with regard to test method development for OECD Test Guideline utility as part of the Mutual Acceptance of Data requirement across all OECD member countries.

Big Question to Developing Solutions: A Decade of Progress in the Development of Aquatic New Approach Methodologies from 2012 to 2022.

In 2012, 20 key questions related to hazard and exposure assessment and environmental and health risks of pharmaceuticals and personal care products in the natural environment were identified. A decade later, this article examines the current level of knowledge around one of the lowest-ranking questions at that time, number 19: "Can nonanimal testing methods be developed that will provide equivalent or better hazard data compared with current in vivo methods?" The inclusion of alternative methods that replace, reduce, or refine animal testing within the regulatory context of risk and hazard assessment of chemicals generally faces many hurdles, although this varies both by organism (human-centric vs. other), sector, and geographical region or country.

Analyses of Transcriptomics Cell Signalling for Pre-Screening Applications in the Integrated Approach for Testing and Assessment of Non-Genotoxic Carcinogens.

With recent rapid advancement of methodological tools, mechanistic understanding of biological processes leading to carcinogenesis is expanding. New approach methodologies such as transcriptomics can inform on non-genotoxic mechanisms of chemical carcinogens and can be developed for regulatory applications. The Organisation for the Economic Cooperation and Development (OECD) expert group developing an Integrated Approach to the Testing and Assessment (IATA) of Non-Genotoxic Carcinogens (NGTxC) is reviewing the possible assays to be integrated therein.

Limitations and uncertainties of acute fish toxicity assessments can be reduced using alternative methods.

Information about acute fish toxicity is routinely required in many jurisdictions for environmental risk assessment of chem­icals. This information is typically obtained using a 96-hour juvenile fish test for lethality according to OECD test guideline (TG) 203 or equivalent regional guidelines. However, TG 203 has never been validated using the criteria currently required for new test methods including alternative methods.

An analysis of the limitations and uncertainties of in vivo developmental neurotoxicity testing and assessment to identify the potential for alternative approaches.

Limitations of regulatory in vivo developmental neurotoxicity (DNT) testing and assessment are well known, such as the 3Rs conflict, low throughput, high costs, high specific expertise needed and the lack of deeper mechanistic information. Moreover, the standard in vivo DNT data variability and in the experimental animal to human real life extrapolation is uncertain. Here, knowledge about these limitations and uncertainties is systematically summarized using a tabular OECD format.

Chemical carcinogen safety testing: OECD expert group international consensus on the development of an integrated approach for the testing and assessment of chemical non-genotoxic carcinogens.

While regulatory requirements for carcinogenicity testing of chemicals vary according to product sector and regulatory jurisdiction, the standard approach starts with a battery of genotoxicity tests (which include mutagenicity assays). If any of the in vivo genotoxicity tests are positive, a lifetime rodent cancer bioassay may be requested, but under most chemical regulations (except plant protection, biocides, pharmaceuticals), this is rare. The decision to conduct further testing based on genotoxicity test outcomes creates a regulatory gap for the identification of non-genotoxic carcinogens (NGTxC).

Contradictory effects of chemical filters in UV/ROS-stressed human keratinocyte and fibroblast cells.

Chemical UV-filters are frequently applied as active ingredients in sunscreen to protect from detrimental effects of UV radiation. Regardless, many of these compounds are not well characterized concerning their capacity to counteract UV induced reactive oxygen species (ROS). Intracellular ROS release is an early event upon UV exposure and a crucial trigger of reaction cascades that may provoke adverse effects both in short- and long-term.

The transformics assay: first steps for the development of an integrated approach to investigate the malignant cell transformation in vitro.

The development of alternative methods to animal testing is a priority in the context of regulatory toxicology. Carcinogenesis is a field where the demand for alternative methods is particularly high. The standard rodent carcinogenicity bioassay requires a large use of animals, high costs, prolonged duration and shows several limitations, which can affect the comprehension of the human relevance of animal carcinogenesis.

Consensus statement on the need for innovation, transition and implementation of developmental neurotoxicity (DNT) testing for regulatory purposes.

This consensus statement voices the agreement of scientific stakeholders from regulatory agencies, academia and industry that a new framework needs adopting for assessment of chemicals with the potential to disrupt brain development. An increased prevalence of neurodevelopmental disorders in children has been observed that cannot solely be explained by genetics and recently pre- and postnatal exposure to environmental chemicals has been suspected as a causal factor. There is only very limited information on neurodevelopmental toxicity, leaving thousands of chemicals, that are present in the environment, with high uncertainty concerning their developmental neurotoxicity (DNT) potential.

International regulatory needs for development of an IATA for non-genotoxic carcinogenic chemical substances.

Although regulatory requirements for carcinogenicity testing of chemicals vary according to product sector and regulatory jurisdiction, the standard approach starts with a battery of genotoxicity tests. If any of the in vivo genotoxicity tests are positive, a lifetime rodent cancer bioassay may be requested, which allows the detection of non-genotoxic carcinogens (NGTxC). However, under most chemical regulations the cancer bioassay is rarely requested, specific requests to obtain information on non-genotoxic mechanisms of carcinogenicity are few, and there are no OECD approved screening methods.