Active pharmaceutical ingredients can persist in the environment

Homeowners who rely on private wells as their drinking water source can be vulnerable to bacteria, nitrates, and other contaminants that have known human health risks. Because they are not connected to a public drinking water supply, the homeowners are responsible for ensuring that their own drinking water is safe.

source https://www.lifetechnology.com/blogs/life-technology-news-blog/active-pharmaceutical-ingredients-can-persist-in-the-environment