The body breaks down and eliminates lots of environmental pollutants in just hours or days. Roundup’s glyphosate stays in the body for several days (assuming there is no additional exposure). Glyphosate is considered non-persistent. But PFAS chemicals are considered persistent:

PFAS tend to remain unchanged in the body for long periods of time. It takes nearly four years for the level in the body to go down by half, assuming there is no additional exposure. This is known as a half life.
–PA Health Department

Four years! And that assumes we’re not adding to our stores every day. Which we are. Bioaccumulation. Imagine livestock exposure. Pet exposure. PFAS are persistent. We need to stop producing them.

This map documents PFAS pollution in public and private water systems. Click the link for the interactive map:
PFAS Contamination in the U.S. (June 8, 2022)

The number of U.S. communities confirmed to be contaminated with the highly toxic fluorinated compounds known as PFAS continues to grow at an alarming rate. As of June 2022, 2,858 locations in 50 states and two territories are known to be contaminated.