Can PFAS in fish and seafood increase your chemical exposure?

What's actually in it

Fish and seafood can contain PFAS (per- and polyfluoroalkyl substances) that accumulate through the food chain. These "forever chemicals" get into waterways from industrial discharge, firefighting foam runoff, and wastewater treatment plants. Fish absorb PFAS from the water and from the smaller organisms they eat, concentrating the chemicals in their tissue.

Unlike mercury, which most people know about in fish, PFAS contamination in seafood has received far less attention. But the levels are high enough to matter.

What the research says

A 2025 study in Environ Pollut measured PFAS levels in fish and water samples from the United Kingdom and Spain. The researchers tested multiple fish species and then estimated what this means for human dietary exposure.

They found measurable PFAS in fish from both countries. The concentrations varied by species and location, with fish from areas closer to industrial activity or urban centers carrying higher levels.

When the researchers calculated dietary exposure for people who eat fish regularly, the contribution from PFAS in seafood was meaningful. For frequent fish eaters, seafood could be one of the largest dietary sources of PFAS exposure.

Don't stop eating fish. The omega-3 benefits are real. But vary the types and sources of fish you eat. Smaller fish like sardines and anchovies tend to have lower PFAS levels than larger predatory fish. Check local advisories for PFAS in your region's waterways.