Thyroid function and immune status in perch (Perca fluviatilis) from lakes contaminated with PFASs or PCBs

The environment contains a multitude of man-made chemicals, some which can act as endocrine disruptors (EDCs), while others be immunotoxic. We evaluated thyroid disruption and immunotoxic effects in wild female perch (Perca fluviatilis) collected from two contaminated areas Sweden; one site with per- polyfluoroalkyl substances (PFASs) sites polychlorinated biphenyls (PCBs), reference included for each area. hepatic mRNA expression receptors ? ?, the hormone metabolising iodothyronine deiodinases (dio1, dio2 dio3) were measured using real-time PCR, levels T3 plasma was analysed radioimmunoassay. In addition, lymphocytes, granulocytes, thrombocytes counted microscopically. Our results showed lower well amounts lymphocytes granulocytes PFAS-contaminated compared to sites. expressions coding enzymes (dio2 receptor (thra) significantly different these fish their site. For at PCB-contaminated sites, there no significant differences or thyroid-related genes, fish. Fish had higher both second PCB lake lake; hence PCBs are unlikely cause this effect. current study suggests that lifelong exposure PFASs could affect status immune defence wild.