Reproductive health indicators of immature common carp exposed to municipal wastewater of Behbahan, Iran

Exogenous estrogens or pollutants with estrogen-like activity can induce vitellogenin (VTG) synthesis in male and juvenile fish, making this protein a useful indicator of chemicals that mimic estrogenic activity. The purpose of this study was to investigate the impact of municipal wastewater on blood biochemical parameters of common carp (Cyprinus carpio). Under experimental conditions, biomarkers such as sex steroid levels, alkali-labile phosphate levels, cholesterol and triglycerides, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) were assessed in immature fish exposed to municipal wastewaters collected from a sewage canal in Behbahan, Khuzestan Province, Iran. No significant changes were found in testosterone levels on day 21; however, estradiol, alkali-labile phosphate, triglycerides, cholesterol, and LDL-cholesterol significantly increased in the fish exposed to municipal wastewater compared with the control group. A significant decrease in HDL-cholesterol levels was observed in the fish exposed to municipal wastewater at the end of the experiment. In conclusion, the results of the present study indicated that sewage effluent of Behbahan may contain endocrine disrupters and exposure to sublethal concentrations of municipal wastewater may cause dysfunction in reproductive health indicators of common carp.