Captured and Contained: Drinking Water Treatment Media Retain PFAS Beyond Their Service Life
This independent study was performed by Dr. Zhi (George) Zhou from Purdue University to address critical knowledge gaps regarding the retention and long-term fate of per- and polyfluoroalkyl substances (PFAS) on point-of-use (POU) and point-of-entry (POE) drinking water treatment media once those media reach end-of-life and are disposed of in a landfill. The study’s objectives were to 1) quantify PFAS retention and desorption behavior from spent activated carbon (AC) filters, reverse osmosis (RO) membranes, and ion exchange (IX) resins; 2) to evaluate breakthrough and exhaustion dynamics; and 3) to assess how environmental conditions, such as, pH, ionic strength, and nitrate influence PFAS retention. The results demonstrated that all treatment media retained PFAS at very high levels, with retention rates ranging from approximately 99.83% to >99.99% across all PFAS compounds. This study is significant because it provides scientifically rigorous, peer-reviewable evidence that PFAS retention from spent treatment media is high under typical disposal-relevant conditions, helping inform regulators, waste managers, and stakeholders about the environmental and public health implications of PFAS treatment media and end-of-life management strategies.