The environmental impact of volatile anaesthetics has traditionally been evaluated primarily in terms of their greenhouse gas contributions. This review broadens the discourse by exploring the ecological ramifications of using fluorinated volatile anaesthetics such as sevoflurane and desflurane, which are classified as Per- and Polyfluoroalkyl Substances (PFAS). These agents not only contribute to atmospheric pollution with their greenhouse effects but also yield degradation products like hexafluorisopropanol (HFIP) and trifluoroacetic acid (TFA) that introduce PFAS into aquatic ecosystems, risking long-term environmental persistence. While Total Intravenous Anaesthesia (TIVA) primarily affects local water systems through renally excreted propofol metabolites, the environmental impact of volatile anaesthetics is significantly broader, encompassing atmospheric deposition and global pollution, exacerbated by the fact that maintenance anaesthesia with sevoflurane requires 20 to 120 times more active pharmaceutical ingredients per hour than TIVA. This bolsters the argument for a critical reassessment of how we quantify ecotoxicity in anaesthetic practices, advocating for a transition to more sustainable alternatives like TIVA. The recognition of PFAS contamination underscores that the current methods for assessing environmental effects of volatile anaesthetics might require greater scrutiny, necessitating a reevaluation of current quantification approaches in response to emerging environmental and health issues associated with PFAS.