Repositori URV

Identifier: TDX:522

Handle: https://hdl.handle.net/20.500.11797/TDX522

Authors:
Alonso Guerra, Virginia

Abstract:
Polybrominated diphenyl ethers (PBDEs) are used as flame retardant additives in a variety of consumer products. Brominated diphenyl ether congener BDE-99 is ubiquitous in the environment and is regarded as one of the most persistent congeners present in wildlife and humans. Experimental studies have evaluated BDE-99 effects on development and reproduction due to pre and perinatal exposure but not in adults. Moreover, previous studies have indicated effects on hormone homeostasis. Although, little is known about their potential toxicological properties.On the other hand, the mechanism through which BDE-99 causes these effects is not well elucidated. This study hypothesized that adverse physiological effects derived from BDE-99 exposure could be due to an imbalance between oxidant agents and antioxidant mechanisms as well as to an hormonal interaction.The aim of the present study was to evaluate the effects of oral BDE-99 exposure on cognitive and reproductive function in adult male rats.In general terms, no alterations on neurodevelopment tests execution were observed. BDE-99 adult exposure caused alterations in sperm morphology, sperm production as well as alterations in seminiferous tubules. Moreover, phagolysosomes in kidney were observed due to BDE-99 administration. In all studied tissues, BDE-99 caused variations in the antioxidant system.Urine biochemical analysis showed changes in renal enzymatic activities and an increase in protein content. In blood, hepatic transaminase activities were also altered by BDE-99 exposure. In addition, testosterone and progesterone levels were decreased.This doctoral thesis shows that oral BDE-99 exposure causes toxic effects in adult male rats that become apparent through an imbalance in oxidative and hormonal status. These variat