Hexafluoropropylene oxide dimer acid (HFPO-DA), a perfluoroalkyl ether carboxylic acid (PFECA), shows diverse biological impacts across species. At 250 µM, it triggers apoptosis and enhances reactive oxygen species (ROS) levels in HepG2 cells. In hatchling chickens, HFPO-DA at a dosage of 4 mg/kg per egg notably decreases right ventricular wall thickness, accelerates heart rate, and promotes hepatic lipid accumulation, though these effects are mitigable by silencing the Ppara gene. It significantly reduces zebrafish embryo survival (LC50 = 7,651 mg/L). Additionally, when administered to pregnant dams at 250 mg/kg, it results in reduced average birthweight, decreased survival time, and lowered serum glucose levels, alongside increased serum cholesterol and triglyceride levels in neonatal rats. HFPO-DA has also been identified as a contaminant in sea and river water.