Cat food’s ‘99%’ lead finding: what the study actually shows

Clean Label Project released a US cat-food study on October 2, 2026, reporting detectable lead in 99 of 100 products tested across 62 brands. The finding raises questions about what reaches pets’ bowls, but it does not mean 99% of all brands are contaminated or that the tested foods caused illness.

The central limitation is explicit. As executive director Molly Hamilton told CNN, the study “does not determine whether a specific product will cause harm to a cat.” Its headline number measures detection in a sample, not the proportion of cats harmed.

What the cat-food study’s 99% figure means

According to Clean Label Project’s announcement, the nonprofit bought 100 top-selling products and tested them for more than 122 contaminants, including metals, pesticides, herbicides and plastic-related chemicals. Its sample included 31 dry foods, 40 wet foods and 29 air-dried or freeze-dried foods.

Lead was detected in 99% of those products, cadmium in 96% and arsenic in 94%. Because the sample contained exactly 100 products, the lead figure represents 99 tested products. Products and brands are different denominators: those results cannot be converted into a percentage of all brands on sale.

Why the study compared calories, not food weight

Clean Label Project’s study webpage explains that results were expressed per 1,000 kilocalories, using each product’s labelled calorie density. Wet food contains substantially more water than dry food, so comparing equal weights would not compare the amount a cat eats to obtain the same energy.

On that calorie-adjusted basis, dry foods carried roughly three times as much lead as wet or air-dried products, the nonprofit reported. This is a comparison of contaminant levels within the study, not evidence that dry food produced three times as much illness.

Fish and seafood products contained about 18 times more mercury overall and about 2.5 times more cadmium than other products. Among wet foods, fish-based products contained about 28 times more mercury than those made with other proteins, according to the announcement.

Nearly 85% of poultry-based products met the organisation’s purity standard, compared with 25.7% of fish and seafood products. Those are results against Clean Label Project’s own standard, not government safety-test pass rates. Hamilton also told CNN: “We certified several fish-based foods.” The group averages do not describe every individual product.

What the testing found beyond heavy metals

CNN reported detectable glyphosate in 37% of tested products. Clean Label Project associated each additional plant ingredient among the first ten on a label with roughly 40% higher glyphosate levels. That association does not establish how contamination reached any particular product.

The plasticizer DEHP was detected in 48 of the 100 products. Where detected, levels in canned and pouched foods were about five times those in bagged products, according to Clean Label Project. Its announcement says contaminants can enter through ingredients, processing or packaging; it does not suggest they were intentionally added.

What manufacturers and an outside scientist said

The Pet Food Institute, which represents manufacturers, defended the industry’s safety systems in CNN’s report. Chief executive Elise Fennig said these include ingredient specifications, supplier verification, testing protocols, traceability and preventive controls.

“Cat owners should feel confident that the food they feed their pets is safe and produced according to rigorous regulatory and quality standards,” Fennig told CNN. Her response describes manufacturers’ safeguards; it is not an independent retest of the sampled foods.

Ryan Babadi, science director at consumer product safety organisation Toxic Free Future, told CNN the work appeared to be a “reasonably conducted analysis”. Babadi was not involved in the investigation. He urged retailers to require suppliers to remove harmful chemicals from food and packaging.

Does detecting metals establish harm to cats?

The report’s limitations prevent that conclusion. Each product was tested from one batch, so the work cannot capture variation between batches. Most brands contributed only one product, and the report restricted brand-level statements to brands with at least three tested products.

The report ranks products against their category rather than regulatory thresholds. Clean Label Project also operates a Purity Award certification programme. Its rankings provide a benchmark for comparing contamination, rather than a determination that a particular food will harm a cat.

Separate research by Bengü Bilgiç and colleagues, published on April 14 in Veterinary Research Communications, examined 300 dry cat foods and 750 cats. It measured metals in food, household drinking water, serum and hair—a different study design from October’s product testing.

That study found higher cadmium in fish- and red-meat-based foods than poultry foods, but no consistent accumulation in biological samples by protein source or feeding duration. Measured blood values remained within physiological reference ranges. The authors nevertheless cautioned that their observational, cross-sectional design could not exclude long-term accumulation or chronic-exposure risk.

What happens after the cat-food report?

Clean Label Project has released its report and rankings and called for closer scrutiny of ingredients, sourcing and finished products. Its announcement does not specify a timetable for manufacturer changes or a follow-up study measuring health outcomes in cats. Those outcomes remain outside what the new testing establishes.