Clean Label Project cat food study finds lead in 99% of tested products

An investigation released on 2 October has put an uncomfortable question behind the cat-food bowl: how much can an ingredient label tell you about contaminants? The Clean Label Project, a US nonprofit that tests and certifies consumer products, says it analysed 100 cat foods from 62 brands for more than 122 contaminants.

Its published findings report lead detected in 99% of the products tested. Cadmium appeared in 96% and arsenic in 94%. Those are detection rates within this sample, rather than percentages of cats harmed. The report also found differences between food formats and protein sources.

The findings received fresh CNN reporting on 2 October. For UK readers encountering the headlines, the useful distinction is between a laboratory result, a product comparison and evidence of harm. They answer different questions, and collapsing them into one can make a startling number less informative.

What the tests compared

Clean Label Project says it bought the products and used an independent analytical laboratory. The sample included dry, wet, air-dried and freeze-dried foods. It reported more mercury in fish and seafood products, and more lead in dry food, within the tested set.

The full report makes an important measurement choice: contaminant amounts are compared per 1,000 kilocalories, rather than by the same weight of food. Wet food contains more water, so an equal-weight comparison can make it appear cleaner through dilution. Comparing an equal amount of food energy addresses that particular problem.

That is a reason to read the units beside a result. A comparison per kilogram and one per calorie are not interchangeable. Neither, on its own, tells an owner how much contaminant their individual cat has absorbed.

Detection does not establish illness

Each product was tested from a single batch, according to the report's limitations. It cannot show how every later batch of that product will perform. Most brands contributed only one product, so a finding about one recipe is not a verdict on an entire company's range.

Report author Molly Hamilton told CNN that the investigation compares contaminant levels and does not determine whether a particular product will harm a cat. That limitation belongs beside the headline number. Finding a substance, measuring an exposure and establishing a clinical consequence are separate stages of evidence.

CNN also sought an industry response. Pet Food Institute chief executive Elise Fennig said manufacturers use safety and quality controls, including supplier checks, testing and traceability. That is the industry body's response; it does not independently validate every tested batch or dismiss the reported findings.

A shortlist is not a recall list

Readers can inspect the exact products included in the testing. The page also explains its Clean Sixteen selection of products with the lowest contaminant levels. It explicitly says that absence from that shortlist does not necessarily mean a product exceeds federal or state regulations, or could not qualify for certification.

That makes the list a comparison within the organisation's programme, not a recall notice. A brand name alone is also an incomplete match: the recipe, format and tested batch matter. The report is framed around the US market; it does not establish the results for every similarly named product sold in Britain.

For a UK owner, checking the precise recipe is more useful than treating a familiar logo as proof that their own pouch was tested. The remaining question is whether the manufacturer can provide relevant testing information for the product actually being fed.

The question to take beyond the headline

Hamilton's practical suggestion, reported by CNN, is to ask manufacturers whether they test finished food for contaminants and how frequently. That moves the conversation from packaging language to evidence about quality control.

Diet decisions still need a nutritional basis. Cats Protection's feeding guidance recommends complete cat food, meaning food that supplies the necessary nutrients. It says changes should be gradual and advises following a vet's guidance for specialist diets. An abrupt change prompted by a headline can introduce a different problem without answering the original testing question.

The next useful information is product-specific: repeated batch results, how the measurements were made and what they mean for the exact recipe in the bowl. A detection headline can start that enquiry. It cannot finish it.

Sources and update record

Published 3 October 2026. This report covers Clean Label Project's findings released on 2 October, its full report and tested-product register, CNN's same-day reporting and industry response, and current Cats Protection feeding guidance. All five records are linked beside the relevant claims and were checked on 3 October. The testing report is the new development; no illness outbreak or product recall is asserted here.