Deleterious effects of wastewater on the health status of fish: a field caging study

Abstract

tWe carried out a caging field experiment to assess the potential effects of an untreated sewage effluenton the health status of Prochilodus lineatus. We analyzed multiple biomarker responses, which includedmorphological indices, biochemical and hematological parameters as well as oxidative stress mark-ers. In addition, we investigated the energetic demand of that exposure. Our findings showed that fishcaged at the effluent showed a differential physiologic profile, suggesting a strong impact on fish health.Particularly, mortality, monocytosis, transaminase increase, antioxidant enzyme activation, lipid oxida-tive damage in several tissues and hepatic and muscle glycogen depletion were observed. According tomultivariate analysis, oxidative stress markers and metabolic parameters were key biomarkers to con-tribute in separating fish caged at effluent site from those caged at upstream and downstream sites.So, these biomarkers allied to a caging strategy are recommended for future environmental monitoringassessments.