A major new investigation has pulled back the curtain on what’s actually inside the food we feed our cats every day, and the results are pretty unsettling. Testing conducted by the Clean Label Project analyzed 100 of the top-selling cat foods across 62 different brands, screening them for over 122 different contaminants. The findings show toxic plastics, the widely used herbicide glyphosate, and heavy metals like lead, mercury, and arsenic showing up in the vast majority of products, even those marketed as premium or organic.
Because cats tend to eat the same food day in and day out, these toxins can build up in their bodies over time, potentially contributing to serious health issues like chronic kidney disease, which is one of the leading causes of death in older cats. The study found lead in 99% of the samples, cadmium in 96%, and arsenic in 94%. Dry foods seemed to carry the highest concentrations of lead, containing about three times more than wet or air-dried alternatives. Meanwhile, fish and seafood-based formulas were the worst offenders when it came to mercury and cadmium, with some wet seafood products containing nearly 28 times more mercury than poultry-based wet foods.
What’s particularly frustrating for pet owners is that these contaminants aren’t just limited to cheap, low-quality brands. Even high-end, organic, and natural foods tested positive for these harmful substances. The issue often traces back to the ingredients themselves—plants added for vitamins and minerals can carry pesticide residues like glyphosate, while fish can accumulate heavy metals from their environment. There are also concerns about plastics like DEHP leaching into food during processing, especially in canned and pouch-style packaging.
Currently, there are very few strict regulations governing contaminant levels in pet food, meaning the onus is largely on the consumer to navigate this mess. Experts suggest varying your cat’s diet—switching between chicken and fish, for instance—to avoid overloading them on a single type of toxin. It also pays to look closely at the ingredient list; just because a fish-free name is on the box doesn’t mean there aren’t seafood ingredients inside. Ultimately, the best move might be reaching out to manufacturers directly to ask about their quality control and how often they test their batches for heavy metals and pesticides.
