Elisa Brivio Contacts: elisa.brivio@phd.unipi.itORCID: 0009-0003-8342-414XThesis supervisors: Dott. Matteo Tesi Project title: Impact of per- and polyfluoroalkyl substances (PFAS) on male fertility: the canine model. Abstract: Per- and polyfluoroalkyl substances (PFAS) are synthetic chemical compounds that can be found in a wide range of everyday use objects and products. Their presence in the environment is widely spread, and their strong chemical structure allows them to be extremely resistant to degradation. A critical aspect is represented by their ability to bioaccumulate and biomagnify in biological tissues, exerting negative effects on overall health by disrupting hormonal synthesis and signalling, inducing immunotoxicity, increasing risk of cancer and impairing fertility and reproductive functions. As found in human literature, PFAS negatively impact male reproductive ability by reducing semen quality and also by acting as an endocrine disruptor on the synthesis of testosterone. However, this aspect has yet to be studied in dogs. This project will focus on evaluating the impact of PFAS on male fertility in the canine model through in vitro and in vivo approaches on testicular cell lines and on semen samples. The aim of this project is to elucidate the mechanisms underlying PFAS-induced toxicity by performing citotoxicity tests, metabolomic and lipidomic analyses.