The Michigan Department of Health and Human Services (MDHHS) is reminding Michigan residents and visitors to avoid foam on Michigan waterbodies such as lakes, rivers and streams.

Foam can form on any waterbody. Natural foam is usually off-white and/or brown, often has an earthy or fishy scent and tends to pile up in bays, in eddies or at river barriers such as dams.

Sometimes foam can contain harmful chemicals or bacteria. This can include high levels of per- and polyfluoroalkyl substances (PFAS). PFAS-containing foam is usually bright white in color, lightweight and may pile up along shores or blow onto beaches. Some studies in people have found that that repeated high PFAS exposure is linked to liver damage and thyroid disease, among other health effects.

If you come in contact with any foam, MDHHS recommends you rinse off or bathe as soon as possible. According to current science, the risk of PFAS entering the body through skin contact is low. However, coming into contact with foam without rinsing off or bathing can lead to accidentally swallowing foam or its contents.

“We advise you to avoid contact with foam if you can, but if you accidentally come into contact with foam, you should rinse off as soon as possible,” said Dr. Natasha Bagdasarian, MDHHS chief medical executive. “Rinsing off in general after water activities is always a good idea.”

The Michigan Department of Agriculture and Rural Development (MDARD) also recommends that people do not allow their animals to come into contact or swallow foam on waterbodies. Animals are at risk of swallowing foam built up in their fur when grooming themselves. If animals do come into contact with foam, they should be rinsed off and bathed with fresh water. Pet owners with questions related to animals and foam ingestion should contact their veterinarian.

Anyone with questions about exposure to PFAS or foam can call the MDHHS Environmental Health hotline at 800-648-6942. More information is available on the MPART website.