Is PFAS in Pet Food Putting Your Dog or Cat at Risk in 2025?

New research out of Japan is raising fresh questions about how PFAS, the "forever chemicals" linked to a range of health concerns, end up in the food bowls of dogs and cats. Two linked studies, reported by PetfoodIndustry.com, found that fish-based ingredients may be contributing to elevated levels of long-chain PFAS in cats' blood serum. Here's what pet owners need to know, and what it means for the broader PFAS problem in everyday products.

What did the new research find?

According to PetfoodIndustry.com, researchers tracing PFAS exposure in companion animals identified fish-based pet food ingredients as a likely contributor to long-chain PFAS compounds detected in cats' blood. Long-chain PFAS are a class of forever chemicals that persist in the body and environment for years, and fish are known to accumulate these compounds from contaminated water, making seafood-based products a plausible pathway for exposure.

The studies focused specifically on cats and dogs, comparing blood serum levels against dietary patterns. The researchers reportedly found associations between fish-heavy diets and higher long-chain PFAS levels, an association, not a proven cause-and-effect relationship, but one that adds to a growing body of evidence about how PFAS move through the food chain and into household pets.

Who and what is affected?

This matters most directly for cat owners, since felines are often fed fish-based wet food as a dietary staple, sometimes daily. Dogs were also studied, though the fish-ingredient link was described as more pronounced in cats. Pet food brands that source fish or fish meal, whether for flavor, palatability, or omega-3 content, are the ones most relevant to this emerging exposure pathway.

It's worth noting this isn't limited to pet food. PFAS contamination has been documented across a huge range of consumer categories, from cookware to outdoor apparel. PFAS Authority's own scoring of 11,090 products found that 41% fail its PFAS and toxin screen, a reminder that forever chemicals show up far beyond nonstick pans, and pet owners managing PFAS exposure at home are often dealing with it on multiple fronts at once, not just what's in the food bowl.

It's important to be clear about method here, that screen is based on published ingredients, materials, certifications, and manufacturer disclosures, not laboratory testing of each product. You can see how the scoring works on our methodology page.

Why does this matter for pet health?

PFAS exposure has been associated in scientific literature with a range of health concerns in humans and animals, including effects on the liver, thyroid function, and immune response. Long-chain PFAS in particular are known to bioaccumulate, meaning levels can build up over a pet's lifetime with repeated exposure through diet.

Cats already face elevated risk for certain thyroid and kidney conditions as they age, and researchers have raised questions about whether environmental exposures, including PFAS, could play a role, though this remains an area of active study rather than settled science. The Japanese research adds a specific, food-based angle to that broader conversation, it suggests diet, not just environment, could be a meaningful exposure route for household pets.

It's also worth remembering that PFAS contamination in fish is not unique to pet food. Wild-caught and farmed fish used in human food supplies have shown PFAS contamination in various regions, tied to water pollution near industrial sites, military bases, and wastewater treatment facilities. Pet food manufacturers sourcing from the same supply chains would reasonably be expected to face similar contamination risks.

What should pet owners do now?

There's no need for panic, but a few practical steps can help pet owners reduce uncertainty.

• Check ingredient sourcing where possible. Some pet food brands publish information about where fish ingredients are sourced or whether they test for contaminants. Brands that disclose more about sourcing and testing generally give owners more to go on than those that stay silent.
• Diversify protein sources. Rotating between fish-based and non-fish-based formulas may reduce cumulative exposure to fish-derived PFAS, though this is a precaution rather than a guaranteed fix.
• Watch for future disclosures. As this research gets more attention, expect some pet food brands to respond with statements or testing data. Silence from a brand isn't proof of a problem, but it also isn't proof of the opposite.
• Look at your own PFAS footprint. Since pets share your home environment, including cookware, carpets, and water, reducing PFAS exposure broadly can help. Our product finder can help you check other household items for PFAS-related concerns using the same published-data approach described in our methodology.

Bottom Line

Emerging research suggests fish-based pet food ingredients may be one pathway for long-chain PFAS exposure in cats, an association that deserves attention but not alarm. No pet food can currently be called PFAS-free with certainty, and this is a developing area of science. Owners concerned about cumulative PFAS exposure, in pet food and elsewhere, have reason to stay informed and ask brands for more transparency, while treating any single product, including fish-based pet food, as lower concern rather than guaranteed safe.

FAQ

Does this mean fish-based pet food is dangerous?

Not necessarily. The research found an association between fish-based ingredients and higher long-chain PFAS levels in cats' blood, according to PetfoodIndustry.com, but it does not prove that any specific product causes harm. It's a signal for more research and scrutiny, not a confirmed danger.

Should I stop feeding my cat fish-based food?

That's a personal and veterinary decision, not one this article can make for you. Owners uncomfortable with the findings may choose to rotate proteins or ask their vet and pet food brand about sourcing and testing practices.

Is PFAS only a concern in pet food?

No. PFAS Authority's own scoring of thousands of products found PFAS-related concerns across many categories, including cookware and outdoor apparel, not just food. You can explore specific products using our finder tool.