As the summer months approach, the Michigan Department of Health and Human Services (MDHHS) is issuing its annual recommendation that Michiganders should avoid contact with foam they may see on Michigan waterbodies such as lakes, rivers and streams.

The foam may have unknown chemicals or bacteria in it, so it is recommended to avoid contact. Foam can form on any waterbody, but foam on some waterbodies may have high levels of per- and polyfluoroalkyl substances (PFAS). PFAS-containing foam tends to be bright white in color, is often lightweight and may pile up like shaving cream on shorelines or blow onto beaches.

Naturally occurring foam without PFAS tends to pile up in bays, eddies or at river barriers such as dams. Naturally occurring foam is typically off-white and/or brown in color and often has an earthy or fishy scent.