Do chicken eggs contain PFAS forever chemicals from the farm?

What's actually in it

Hens absorb PFAS (per- and polyfluoroalkyl substances) from contaminated feed, water, and soil. The chemicals accumulate in their bodies and get deposited into eggs, concentrating in the yolk. Both factory-farmed hens and backyard chickens are exposed, though from different sources. Commercial hens get PFAS through feed and treated water. Free-range and backyard hens get it from pecking at contaminated soil and bugs.

What the research says

A 2026 study in Foods measured PFAS levels in eggs from commercial farms and home producers. The results surprised the researchers: home-produced eggs from backyard chickens often had higher PFAS levels than factory-farmed eggs.

The likely reason is that backyard chickens forage on open ground. If that soil is anywhere near an area where PFAS has been used (firefighting foam, treated fields, industrial sites), the hens pick it up directly. Factory-farmed hens live indoors and eat controlled feed, which limits some (but not all) PFAS sources.

The study detected multiple PFAS types in the eggs, including PFOS and PFOA, two of the most studied and harmful varieties. Even eggs labeled as organic or free-range aren't guaranteed to be PFAS-free, because the contamination comes from the environment, not from farming practices.

Eggs are one of the most commonly eaten foods in the world. For people who eat two or three eggs a day, the PFAS exposure from eggs alone adds a measurable amount to their total daily intake.