Horsham, Warminster and Warrington had some of the highest levels of the chemicals nationwide in their drinking water when it was first discovered in 2014. The chemicals have been linked by some studies to health effects including elevated cholesterol, ulcerative colitis, low birth weight babies, immunotoxicity, developmental delays, and some cancers. Pennsylvania Department of Health studies have found elevated rates of some cancers in the towns, but results overall have been inconclusive, officials say.

According to the EPA, the July 25 meeting will be an all-day event, featuring a working session from 10 a.m. to 3 p.m. followed by a listening session from 4 to 9 p.m.

The event is open to the press and public, but the EPA is encouraging online registration. Those who wish to speak during the listening session must select that option during online registration, which closes July 20.

Registration can be made at www.epa.gov/pfas/forms/pfas-community-engagement-horsham-pa.