Metabolomics in bivalve mollusks: A review of biomarker discovery for environmental contaminant exposure

This review examines the potential of NMR- and MS-based metabolomics for environmental monitoring using bivalves as bioindicators. Bivalves, particularly mussels, play a vital role in ecological studies by providing critical insights into the impacts of water contamination on aquatic ecosystems. As water pollution continues to pose a growing global challenge, bivalves' environmental and economic importance underscores their value in monitoring programs. Metabolomics, a high-throughput analytical approach, has emerged as a powerful tool for assessing metabolic changes in organisms exposed to environmental stressors. This review explores metabolomics applications across various bivalve species, focusing on identifying biomarkers associated with contaminants and their effects on different organisms. Key aspects of study design are discussed, including extraction techniques, analytical platforms, and the development of tailored protocols to address metabolite class specificity, method efficiency, safety, and reproducibility. Furthermore, we highlight how bivalve metabolomics contributes to biomarker discovery and the elucidation of toxicity mechanisms. By addressing both the benefits, such as its sensitivity and broad applicability, and the challenges, such as sample preparation and data complexity, our review provides a unified perspective on the ecological and human health implications of using bivalve metabolic profiles for environmental biomonitoring.