Dozens of Suffolk homeowners are being urged to use bottled water after a toxic chemical was detected in their water wells.

The Suffolk County Health Department announced Thursday that PFOS, a chemical commonly found in firefighting foam, was detected in wells in East Patchogue.

Although there were no detections of PFOS above health guidance levels in the public water, the Suffolk County Water Authority has taken the wells out of service.

The county says health officials plan to sample private wells in the area at no charge to homeowners as a precautionary measure. Health experts say the chemical may cause cancer and other illnesses.

Gerhard Porsche and his wife, Maria, have lived in East Patchogue for more than 50 years. They told News 12 that the neighborhood has had “plenty of cancer cases.”

The county says it plans to test an estimated 58 properties in East Patchogue and South Medford that are served with a private well.

News 12 has reported that Wainscott, East Quogue and Westhampton Beach were also tested after the discovery of chemicals in the water.

The state’s Department of Environmental Conservation is providing free bottled water to residents who live in the private well testing area.