© by TERRAPUB, 2012. Fish Immunotoxicology: Research at the Crossroads

Abstract—The current testing paradigm used in ecotoxicological hazard and risk assessment is well appropriate for chemicals with non-specific modes of action, the question, however is, whether it is appropriate for specifically acting compounds as well. A specific mode of action that is shown by numerous environmental chemicals is immunotoxicity. Immunity is an ecologically relevant trait, which is of key importance for organism survival and population growth against the pressure of pathogens in their environment. However, the environment also imprints genotypic and phenotypic properties of the immune system. Immunologically relevant environmental factors include pathogens as well as toxic chemicals. A complicating factor in detecting immunotoxic effects is the fact that they may be not evident in the resting immune system, but only after immune activation by pathogen challenge. Consequently, risk assessment of chemical-induced disruption of immune function must focus not alone on the relationship between chemical exposure and the response of selected immune parameters, but it has to consider the complex functional properties of this system in its ecological context