PFAS Levels in Freshwater Fish

Per- and polyfluoroalkyl substances (PFAS) are a large class of fluorinated synthetic chemicals that are toxic, highly persistent, and accumulate in humans, wildlife, and the environment. Over the last decade, government agencies, non-governmental organizations, academics, and many others have researched the nature and extent of PFAS environmental contamination and the extent to which people have been exposed to it, particularly through drinking water pathways. To investigate PFAS in other media, the Massachusetts Department of Environmental Protection collaborated with the U.S. Geological Survey to study PFAS contamination in selected surface waters in Massachusetts. That study, completed in 2021, detected PFAS in all 27 rivers sampled, including at locations upstream of known sources. While that study answered many questions about PFAS in the Massachusetts environment, it raised others: To what extent are freshwater fish from these and other waterbodies contaminated with PFAS? What are the contamination levels in lakes and ponds? Are risk management actions needed to reduce human exposure in fish and surface water? To help answer these and other questions, MassDEP contracted with ERG.  

ERG designed and executed a field study to characterize PFAS concentrations in surface water and edible tissue of commonly consumed freshwater fish from lakes, ponds, and rivers throughout Massachusetts, including several waterbodies in and near environmental justice communities. In consultation with MassDEP, ERG prepared a quality assurance project plan and sampling and analysis plan. With assistance from a subcontractor (Normandeau Associates), ERG ensured that all sampling and laboratory analyses were conducted according to the plans. Overall, sampling occurred at 52 lakes, ponds, and rivers throughout the Commonwealth. From these waterbodies, the field team collected 66 surface water samples and 948 fish from 16 different species, all of which were analyzed for 40 PFAS using draft EPA Method 1633. ERG conducted statistical analyses of the large data set and authored the project’s final report, “PFAS Concentrations in Surface Water and Fish Tissue at Selected Rivers and Lakes in Massachusetts.” The report describes numerous key findings, including the range of PFAS concentrations found in freshwater fish; the presence of PFAS in all waterbodies (including waterbodies in rural areas far from known and suspected sources); and insights into bioaccumulation factors. State agencies have been using this project’s extensive data to make risk management decisions about the presence of PFAS in surface waters and implications for fish consumption and recreational swimming.