In a new study, natural foams and water surface microlayers of 43 Wisconsin rivers and lakes were found to contain 36 compounds in a group of chemicals known as PFAS. While PFAS were detected in both the foam and the water surface, it’s the foams that the researcher said were orders of magnitude higher in PFAS concentration compared to water, and they urge people and their pets to avoid them. The study also revealed that foams, generally off-white and found along shorelines on windy days, are not an indicator of elevated contamination levels in the entire water body.

Leading the project is Christy Remucal with the University of Wisconsin-Madison Department of Civil and Environmental Engineering and interim director of the University of Wisconsin Aquatic Sciences Center.