Developmental Effects of a Non-Dioxin-Like Polychlorinated Biphenyl Mixture on Zebrafish (Danio rerio)

PCBs are synthetic organic compounds known for their toxicity to many organisms and are notorious for having large discrepancies between measured and nominal concentrations. Historically thought to be less toxic, non-dioxin-like (NDL) PCBs represent the majority of congeners and are capable of eliciting neurotoxic effects. NDL-PCBs remain understudied, including their effects on aquatic organisms. In the first study, I collected extensive chemistry data and data on neurobehavioral and cardiac endpoints to test the acute effects of exposure to an NDL-PCB mixture on early life stage zebrafish. Neurobehavioral effects observed in the first study indicated a potential for longer term behavioral effects in these fish. In the second study, I collected data on feeding, social, and memory behavior of zebrafish at time points beyond the acute exposure from the first study. Acute and longer-term behavioral endpoints in the first and second studies demonstrated effects from PCB exposure but did not indicate mechanisms. In the third study, I collected untargeted and targeted metabolomic data on amino acid, sugar, anionic compound, and neurotransmitter profiles to determine the specific pathways affected by exposure to an NDL-PCB mixture. These combined data from these studies provide a unique insight into the chemical profile of an NDL-PCB mixture in biological applications and synthesize acute, longer-term, and mechanistic effects on developing zebrafish. These data fully illustrate an adverse outcome pathway from toxicokinetic to population level effects.