Developmental deformities and biochemical disruptions in zebrafish (Danio spp) embryos and adults following exposure to perfluorooctanoic acid (PFOA) and perflurorooctanesulfonic acid (PFOS)

Abstract

Perfluorooctanoic acid (PFOA) and Perfluorooctanesulfonic (PFOS) are metabolites of perfluorinated chemicals, which are persistent compounds due to their chemical structure and inability to be broken down. The purpose of this investigation is to determine the mechanism of action of both compounds as developmental and adults toxicants. To determine possible mechanisms of action, various endpoints were assessed included: (1) presence of anatomical changes, (2) alterations in hatching and mortality, and (3) changes in acetylcholinesterase, and glutathione s- transferase activities. Zebrafish embryos and adults were ideal models to investigate developmental changes as well as perturbations in mature systems, due to ease of tracking desired changes. Results indicate disruption of hatching as well as a delayed response or death at 50 mg/L for both PFOA and PFOS. In addition, inhibition of acetylcholinesterase (AChE) activity by PFOA was observed in zebrafish muscle, while no noticeable changes were observed with brain AChE activity following exposure to PFOA. No changes were observed in brain and muscle tissue of zebrafish exposed to PFOS. Glutathione s- transferase (GST) induction was also observed at lower concentrations in PFOS, while no change in GST activity was observed in zebrafish livers following PFOA exposure