A new analysis of 100 cat food products from 62 brands found detectable levels of lead in 99% of samples, cadmium in 96%, and arsenic in 94%, according to the nonprofit Clean Label Project. The pet food industry's main trade group disputes the findings, arguing the study measured products against a private purity standard rather than any regulatory safety threshold — and that detecting a contaminant isn't the same as proving harm.

What Was Tested, and How

Clean Label Project said an independent, ISO 17025-accredited lab tested 31 dry, 40 wet (canned and pouch), and 29 air-dried or freeze-dried products for more than 122 environmental contaminants and toxins, using ICP-MS for heavy metals and LC-MS/MS for other chemicals. The group reported results per 1,000 kilocalories rather than per kilogram of food, arguing that weight-based reporting makes high-moisture wet food look artificially cleaner. Combined with earlier testing, the group's full dataset now covers 541 samples from 87 brands.

Fish-Based Formulas Tested Far Higher for Some Metals

  • Lead was detected in 99% of products overall, cadmium in 96%, and arsenic in 94%.
  • 84.8% of poultry-based products met the group's purity standard, compared with 25.7% of fish and seafood products.
  • Fish- and seafood-named products had roughly 18 times more mercury than other formulas once format was accounted for; among wet foods specifically, the gap widened to about 28 times.
  • Dry food had roughly three times more lead than wet or air-dried food per calorie.
  • Glyphosate, a widely used herbicide, was found in 37% of products, rising with the number of plant ingredients near the top of the ingredient list.
  • A plasticizer, DEHP, was found in 48 of 100 products, at roughly five times higher levels in canned and pouched foods than in bagged ones.

No specific brands were named in the public reporting on the study. Herring meal, tuna and fish broth were the ingredients most consistently linked to higher contamination across the group's combined dataset.

The Pet Food Industry's Response

Pet Food Institute CEO Elise Fennig disputed the study's framing in a statement to trade publication Petfood Industry. She said the report measures products against a proprietary "purity standard" rather than science-based risk assessments or regulatory limits, and that it's unclear whether the methodology received outside scientific or veterinary review. Fennig noted the substances tested aren't intentionally added ingredients — they can occur naturally in the environment — and cited FDA guidance that whether a substance causes harm depends on the level and duration of exposure, not simply its presence. She added that U.S. pet food manufacturing is highly regulated and that companies run their own supplier verification and testing programs.

An unresolved dispute

Clean Label Project's findings describe the presence and relative levels of contaminants; the group did not publish toxicity thresholds or health-outcome data in the reporting reviewed for this story. The Pet Food Institute, in turn, offered no contaminant-level data of its own. Neither the FDA nor any state agency has announced a recall or formal safety action tied to this specific study.

What This Means for Cat Owners

Veterinary and nutrition experts generally recommend variety in diet and watching for recalls through official FDA and manufacturer channels rather than reacting to any single advocacy-group study. If you have concerns about a food you feed your cat, your veterinarian can advise on whether a switch is warranted — this study, on its own, identifies a measured chemical presence, not a confirmed health risk for any individual product or brand.