The use of spontaneous behavior, swimming performances and metabolic rate to evaluate toxicity of PFOS on topmouth gudgeon Pseudorasbora parva

Perfluorooctane sulfonate (PFOS) is a ubiquitous environmental contaminant that has been found to pose various risks to fish health and the safety of aquatic ecosystem. Swimming performance is an integrated index of fitness in fish. However, little research has sought on the effects of PFOS on swimming performances of fish. Experiments were carried out to clarify the impacts of acute exposure to PFOS on behavior, swimming ability and metabolic rate in topmouth gudgeon (Pseudorasbora parva), to understand the underlying ecotoxicological effects of waterborne PFOS exposure on fish physiology and behavior. Fish were exposed to PFOS (0, 0.5, 2, 8 or 32 mg/L) for 96 h. Afterwards, the routine metabolic rate (RMR), spontaneous swimming behavior (SSB), fast-start swimming performance (FSP) and critical swimming speed (Ucrit) of the topmouth gudgeon were examined. The results show reduced behavioral performance and increased physiological stress with increasing PFOS concentration. Both RMR, SSB and Ucrit were significantly affected by PFOS exposure (p < 0.05). The lowest observed effect concentration (LOEC) is 2 mg/L for SSB. PFOS treatment resulted in increased RMR (p = 0.001) and decreased Ucrit (p = 0.005), whereas FSP was not influenced by PFOS (p > 0.05). The results indicate that the anaerobic swimming capacity was conserved, but the metabolic level, SSB and aerobic swimming performance in topmouth gudgeon were susceptible to PFOS contamination, and hence might be useful as considerable potential biomarkers of pollution.