The mechanisms behind toxic effects of POPs

Environmental exposure to persistent organic pollutants (POPs) such as dioxins, polychlorinated biphenyls (PCBs), organochlorine pesticides (OP) and brominated flame retardants (BFRs) is an emotive and sensitive subject. Questions have been raised among t he scientific community, policy makers and general public regarding the potential hazard of POPs in the environment to human and animal development and health. Particular attention has been given to xenobiotic compounds that are capable of modulating or d isrupting the endocrine system. Special concerns have been raised whether environmental exposure may cause adverse effects in sensitive populations such as the fetus and the developing infant. However, the knowledge about these chemicals, their sources, e nvironmental behaviour, and toxicity is extremely limited, precluding the completion of a comprehensive risk assessment. This proposal seeks to establish whether "real life" mixtures of POPs have potential to disrupt the development and function of the hu man reproductive- and immune systems by using in vitro and in vivo methods combined with genomics. Data from studies with cell models will be compared with data from animal exposure studies in order to enable elucidation of differences between in vivo and in vitro situations and to better understand mechanisms of action. The project will use cell cultures and selected tissues in animals and man. The application of the same cell types from various species enables the comparison of effects and mechanisms fo r toxicity between different species leading to more valid extrapolation to the situation in humans