Exposure to wastewater effluent disrupts hypoxia responses in killifish (Fundulus heteroclitus)

Hypoxia (low oxygen) often occurs in aquatic ecosystems that receive effluent from municipal wastewater treatment plants (WWTP). The combination of hypoxia and WWTP could impair fish health, because contains multiple contaminants disrupt the physiological pathways use to cope with hypoxia, but interactive effects these stressors on physiology are poorly understood. We have examined this issue by exposing mummichog killifish ( Fundulus heteroclitus ) (5 2 kPa O and/or 100% for 21 days a full factorial design. then measured tolerance, whole-animal metabolism, gill morphology, haematology, tissue metabolites. In clean water, responded chronic improvements as reflected increases time loss equilibrium at 0.5 (t LOE ). These occurred association exposed surface lamellae resulted regression interlamellar cell mass (ILCM). Concurrent exposure attenuated t remodeling nearly depleted brain glycogen stores. Therefore, can mechanisms tolerance. Our research suggests near WWTPs health fish. • Receiving waters (WWTP) be hypoxic. Combined Killifish were Wastewater disrupted underlying physiology. health. Combinations low oxygen