Effects of chronic perfluorooctanoic acid (PFOA) at low concentration on morphometrics, gene expression, and fecundity in zebrafish (Danio rerio)

- Zebrafish exposed to PFOA long-term had detrimental effects in growth fecundity.
- Offspring of zebrafish long-term exposed to PFOA were delayed in early development.
- Organic anion transporter genes were altered in expression after long-term PFOA exposure.

Perfluorooctanoic acid (PFOA) is a persistent, toxic, anthropogenic chemical recalcitrant to biodegradation. Based on previous studies in lower and higher vertebrates, it was hypothesized that chronic, sub-lethal, embryonic exposure to PFOA in zebrafish (Danio rerio) would adversely impact fish development, survival, and fecundity. Zebrafish embryo/sac-fry were water exposed to 2.0 or 0 nM PFOA from 3 to 120 hpf, and juvenile to adult cohorts were fed spiked food (8 pM) until 6 months. After chronic exposure, PFOA exposed fish were significantly smaller in total weight and length. Gene expression analysis found a significant decrease of transporters slco2b1, slco4a1, slco3a1 and tgfb1a, and a significant increase of slco1d1 expression. PFOA exposed fish produced significantly fewer eggs with reduced viability and developmental stage delay in F1. Chronic, low-dose exposure of zebrafish to PFOA significantly altered normal development, survival and fecundity and would likely impact wild fish population fitness in watersheds chronically exposed to PFOA.