(CNN)-- An environmental advocacy group says, your tap water may contain elevated levels of "Forever Chemicals" or PFAs. Perfluoroalkyl substances are manmade chemicals that have properties that allow them to repel both water and oil.
The chemicals got the name "Forever Chemicals" because they don't break down naturally in your body. This will cause them to build up in your system over time, increasing the risk of cancer. However, these toxins are not only limited to cancer, but they also can reduce the effectiveness of vaccines and harm the development of fetuses.
Some of the highest PFA levels were detected in water sampled from major metropolitan areas.