ToxiGen - Reproductive toxicity and transgenerational effects of petroleum mixtures in fish

A fundamental and enduring challenge for ecosystem managers developing risk and impact assessment tools is to predict the extent of impact that spilled oil can have on the immediate fish populations and on future generations. Modelling approaches are important tools for these assessments, but they currently suffer from two major shortcomings: 1) the failure to acknowledge that effects can be transferred through several generations and 2) the assumption that a small group of toxic compounds, polycyclic aromatic hydrocarbons, can be used as chemical proxy for exposure to complex petroleum mixtures. Emerging understanding within petroleum ecotoxicology now suggests that model outputs lack robustness. Up until now studies have not been able to determine the effects over multiple generations, and to properly identify the causative agents within petroleum. ToxiGen is an interdisciplinary study that will determine the effects and toxic mechanisms of petroleum on the reproductive success of fishes and subsequent generations. Our ambition is to identify the compounds responsible for alterations in reproductive success in adults and survival and fitness of the progeny. We will work with Atlantic cod and polar cod that are of high ecological and commercial importance, respectively. Zebrafish will be used for high-risk and generational experiments. We will work at the frontier of analytical chemistry to characterize the toxic fractions of petroleum. To disentangle mechanisms of toxicity, novel methods such as micro-injecting compounds into eggs will be used. We will combine different approaches to identify new biomarkers of exposure and effects. The new knowledge will then be integrated into reproductive adverse outcome pathways to be available through an internationally harmonized knowledgebase. Ultimately, ToxiGen will provide environmental managers with knowledge and data for models, and methods to detect and monitor the presence and impact of these complex mixtures in situ.