Lead, cadmium and arsenic appeared in almost all of 100 popular cat food products tested in a new study, while researchers also detected mercury, glyphosate and chemicals associated with plastics.
The Clean Label Project tested 100 products from 62 brands for more than 122 potential contaminants, with the findings reported by CNN raising questions about the levels of certain substances in cat food and how they vary according to the type of food and its protein source.
Researchers detected lead in 99% of the samples, cadmium in 96% and arsenic in 94%. They also tested the products for mercury and other contaminants.
Molly Hamilton, the organisation’s executive director, noted that cats often eat the same food almost every day. She said repeated exposure to some contaminants could therefore contribute to their accumulation in the animals’ bodies over time.
Lead detected in 99% of samples
The study found significant differences in contaminant levels depending on whether the food was wet, dry, air-dried or freeze-dried, as well as on the source of its protein.
Dry food contained about three times as much lead as wet, air-dried or freeze-dried food, according to the analysis.
Foods that relied primarily on fish or seafood as their protein source showed particularly high levels of mercury and cadmium. Mercury levels in those products were about 18 times higher, while cadmium levels were about 2.5 times higher than in foods based on other protein sources.
Glyphosate also detected
The researchers also tested for glyphosate, one of the most widely used agricultural herbicides. They detected the chemical in 37% of the products.
The study found that products containing more plant-based ingredients among their top 10 ingredients generally had higher average levels of glyphosate.
Researchers also detected DEHP, a phthalate compound used in PVC plastics and some food-contact materials, in about half of the products. The highest levels appeared in canned and pouch-packaged foods.
Experts and industry respond
Ryan Babandi, science director at Toxic Free Future, described the research as generally credible and said retailers and manufacturers should ensure that potentially harmful chemicals do not enter pet foods or their packaging.
The Pet Food Institute, which represents the pet food industry, said manufacturers follow strict safety and quality-control protocols. These include raw-material inspections, supplier assessments, laboratory testing and traceability systems designed to ensure that products remain safe and nutritionally appropriate.
Study has important limitations
The findings also require context because the study has several limitations.
Researchers tested only one batch of each product, meaning the results cannot capture potential differences between batches of the same food.
The study also measured the presence and levels of specific contaminants in the products it tested. It did not establish that any particular product causes harm to a cat’s health.
