This series of articles explores how PFAS (forever chemicals) contaminate our water and food, and what we can do about it. PFAS are synthetic chemicals that can cause cancer, birth defects, liver problems, damage to the immune system, and other serious health problems. They are of particular concern to rural people who get their water from wells and live near military bases, factories that use PFAS, or farmland where sewage sludge has been land applied.