Early warning and prioritization of contaminants of emerging concern for risk assessment

Contaminants of emerging concern (CECs), including persistent and bioaccumulative substances (e.g., PFAS), micro/nanoplastics, pharmaceuticals, and their environmental transformation products, are an increasing challenge for toxicology, environmental monitoring, and regulatory decision-making because they may threaten water quality, ecosystem integrity, and human health before their risks are fully characterized. Their diverse chemical properties, occurrence in complex mixtures, continuous introduction into the environment, and often limited mechanistic toxicity data make early identification and prioritization difficult. These challenges raise important questions about how existing toxicological evidence, exposure information, effect-based tools, new approach methodologies (NAMs), and computational predictions can be integrated to support timely and scientifically robust decisions. Recent advances in high resolution analytical platforms, non-target screening (NTS), high-throughput testing, omics-based approaches, read-across, adverse outcome pathway frameworks, machine learning, and geospatial exposure assessment provide new opportunities to address these limitations. However, important gaps remain in data quality and interoperability, the validation and interpretation of predictive models, the assessment of combined exposures and multiple stressors, and the translation of molecular- and cellular-level findings into organism, population, ecosystem, and human health outcomes. Adaptive approaches are therefore needed in which models guide monitoring and testing, while newly generated evidence continuously improves risk predictions and prioritization.This Research Topic aims to advance toxicologically informed and data-driven approaches for the early warning, characterization, and prioritization of CECs. It will provide a forum for research that integrates mechanistic toxicology, exposure science, experimental evidence, NAMs, in silico methods, and artificial intelligence to identify emerging risks and improve the efficiency of testing and monitoring strategies. Contributions may address how these approaches can support the evaluation of individual chemicals and complex real world mixtures, strengthen human health and ecological risk assessment, and facilitate transparent, evidence- based regulatory decision- making. The Research Topic will also encourage work that evaluates the applicability, uncertainty, transferability, and regulatory relevance of emerging tools across different environmental and biological contexts.To gather further insights into the early identification and prioritization of CECs in across environmental matrices (aquatic, terrestrial, atmospheric, and circular waste streams), this Research Topic will consider studies spanning experimental, computational, monitoring, and regulatory perspectives. We welcome articles addressing, but not limited to, the following themes:o Early-warning indicators, non-target screening (NTS), suspect screening, and prioritization frameworks for CECs and their transformation productso Effect- based monitoring and bioassay- directed approacheso New approach methodologies, including high-throughput and omics-based toxicologyo Adverse outcome pathways and mechanistic approaches to hazard characterizationo Mixture, cumulative, and multiple-stressor toxicityo In silico toxicology, read-across, machine learning, and artificial intelligenceo Integration of analytical discovery, occurrence, toxicity, and exposure datao Geospatial and spatiotemporal exposure assessmento Links between molecular or cellular responses and organism, population, or ecosystem effectso Human health and ecological risk assessment for CECs in environmental system and resource recovery processeso Uncertainty analysis, model validation, and explainabilityo Translating data- driven evidence into monitoring strategies and regulatory decision- makingo Frameworks supporting evidence-based policymaking and relevant Sustainable Development Goals Topic editors: Mohammad Sadia, Dominique M. Narain-Ford Source: https://www.frontiersin.org/research-topics/85649/early-warning-and-prioritization-of-contaminants-of-emerging-concern-for-risk-assessment