Per- and polyfluoroalkyl substances (PFAS) are highly persistent, harmful chemicals with complex environmental transport behaviour. PFAS have emerged as a concerning class of contaminants, with over 4000 non-naturally occurring chemicals displaying widespread environmental presence. The long lasting , bio accumulative, and toxic properties of certain PFAS compounds, notably PFOS and long-chain PFCAs, have regulatory action. However, the use of alternative compounds with poorly understood environmental behaviours continues. Despite growing calls for improved management, there remains a significant knowledge gap regarding biota exposure to PFASs.
In this research, the impact of PFAS is assessed by exposing the mussels to PFAS mixtures, mimicking environmental contamination through water and food in controlled tanks for 28 days, followed by 14 days depuration phase. By using distinct 13 C isotopic labelling , the study traced the sources of contamination. The analysis compared control mussels with PFAS-exposed ones from various tank conditions, evaluating health effects through using oxidative stress biomarkers (CAT, SOD, LOOH), a detoxification marker (GST), and a neurotoxicity marker (AChE). Early molecular responses were investigated by measuring the relative expression of genes associated with cell proliferation, apoptosis, cellular stress, and energy metabolism through qPCR analysis. Furthermore, the condition index of individual mussels was assessed to evaluate overall health and condition, and a lipidomic analysis was performed to investigate alterations in lipid profiles in response to varying exposure conditions.
This research sheds light on the biochemical and molecular responses of blue mussels to simultaneous exposure to PFAS through waterborne and foodborne routes. By enhancing our understanding of the risks associated with these contaminants, the findings contribute significantly to the field of ecotoxicology and aid in the development of more effective management strategies.