Lead turned up in 99 of every 100 cat foods tested in a new cat food study from the Clean Label Project, a Colorado nonprofit that tests consumer products for contaminants. The results, released Friday, Oct. 2, 2026, and first reported by CNN, also found cadmium in 96% of products, arsenic in 94%, the herbicide glyphosate in 37% and a plastic chemical called DEHP in nearly half.
The group bought 100 top-selling cat foods from 62 brands at retail and had an independent lab screen them for more than 122 contaminants. Every format was affected, including products marketed as natural or premium. But the report is careful about one point: it measured how much of each substance was present and ranked products against each other. It did not show that any food made a cat sick.
What the cat food study tested
According to the Clean Label Project’s published summary, the sample included 31 dry kibbles, 40 wet foods in cans or pouches, and 29 air-dried or freeze-dried products. An ISO 17025-accredited lab ran the tests, and results were converted to micrograms per 1,000 calories rather than per kilogram of food.
That matters because wet food is mostly water, so a cat eats about four times as much of it by weight to get the same calories.
Report author Molly Hamilton, the nonprofit’s executive director, said the daily routine of most pets is what makes the findings relevant.
“Most cats eat the same foods nearly every day, with little variation,” Hamilton told CNN.
She added that chronic kidney disease is among the most common causes of death in older cats, and that the kidneys do much of the work of filtering heavy metals.
Fish, chicken and the “whack-a-mole” problem
Protein source was the strongest predictor: fish-based cat foods carried about 18 times more mercury and about 2.5 times more cadmium than foods made with other proteins. Among wet foods, the gap in mercury was close to 28 times. Nearly half (48.6%) of fish and seafood products landed among the highest for mercury, while no poultry-based product did.
Overall, 84.8% of poultry products met the group’s purity standard, compared with 25.7% of fish and seafood products. “It’s a whack-a-mole situation,” Hamilton said, explaining that chicken did better on mercury and cadmium but showed higher rates of lead and herbicides.
Pooling this round with earlier testing, 541 samples across 87 brands, the group found herring meal, tuna and fish broth most strongly tied to contamination. Products with herring meal landed in the most contaminated 10% of products 60% of the time.
Why dry cat food carried more lead
Dry cat food had roughly three times the lead of wet or air-dried products, and the gap held regardless of protein. The products with the highest lead levels had about 3.5 times more than the typical product.
Plants, glyphosate and a plastic chemical in the can
Cats are carnivores, but many recipes add vegetables and legumes. Glyphosate levels rose about 40% for each additional plant ingredient among the first ten on the label. The study also found that in 35 of 100 products, the first-listed ingredient, usually meat or fish, was outnumbered by ingredients from another category within the top ten. Listing one crop several times in different forms is known as “ingredient splitting,” and it is allowed.
DEHP, a phthalate used in flexible PVC plastics, was detected in 48 of 100 products. It appeared at similar rates in every format, but canned and pouched foods carried about five times as much where it was found. Ryan Babadi, science director at the nonprofit Toxic Free Future, who was not involved in the work, called its spread a “very concerning finding.” There was better news on packaging: BPA showed up in only two products and BPS in one.
What the cat food study does not show
Every product was tested from a single batch, so the results cannot capture differences between production lots. Hamilton was explicit about the limits, as quoted in CNN’s report, carried by KION:
“It does not determine whether a specific product will cause harm to a cat.”
She also noted that few rules govern contaminants in pet food. “The absence of safety standards does not mean a contaminant is safe,” she said. Babadi said the work “appears to be a reasonably conducted analysis.”
The full list of products tested and the group’s top-ranked foods sit behind an email sign-up on its website. Publicly, the nonprofit names three companies whose cat foods carry its certification seal: Bixbi, Freshpet and Smalls. Hamilton said no brand helped choose products, run tests or analyze results, and none saw the findings before publication.
Pet Food Institute pushes back
The Pet Food Institute, which represents cat food makers, told CNN that manufacturers run food safety programs with “ingredient specifications, supplier verification, testing protocols, traceability systems, and science-based preventive controls.” CEO Elise Fennig said: “Cat owners should feel confident that the food they feed their pets is safe and produced according to rigorous regulatory and quality standards.” No response from the FDA was included in the reports reviewed for this article.
Practical steps for cat owners after the cat food study
The report’s advice is about trimming exposure, not panic:
- Rotate proteins. If your cat eats fish-based food exclusively, mix in chicken or other proteins. Foods without fish in the name can still contain marine ingredients.
- Consider format. Wet or air-dried food carried less lead than dry kibble.
- Read past the first ingredient. Long strings of similar plant ingredients near the top were linked to more lead and more herbicide residue.
- Ask the brand. Hamilton advises contacting the manufacturer to ask whether, and how often, it tests finished products.
- Keep the cat eating. The group notes that for picky cats, a complete diet they will actually eat remains the priority.
For other food safety news closer to your own plate, see our roundup of three food recalls to check your kitchen for.
