Transcriptional impact of organophosphate and metal mixtures on olfaction: copper dominates the chlorpyrifos-induced response in adult zebrafish.

Chemical exposures in fish have been linked to loss of olfaction leading to an inability to detect predators and prey and decreased survival. However, the mechanisms underlying olfactory neurotoxicity are not well characterized, especially in environmental exposures which involve chemical mixtures. We used zebrafish to characterize olfactory transcriptional responses by two model olfactory inhibitors, the pesticide chlorpyrifos (CPF) and mixtures of CPF with the neurotoxic metal copper (Cu). 30 one-year-old adult AB strain zebrafish were exposed, in groups of three, to CPF/Cu concentrations of 0/0, 0.1/0, 0.25/0, 0.6/0, 0/0.1, 0/0.25, 0/0.6, 0.1/0.25, 0.25/0.25, 0.6/0.25.