Between November 22, 2023, and April 15, 2024, the US Food and Drug Administration (FDA) received approximately 1,300 adverse event reports for a variety of Purina pet foods.

Today (July 31, 2024) after more than half a year of follow-up work, including pet owner interviews, lab analyses, and a plant inspection, the agency released the results of its investigation.

Initial triage of complaints

Following an initial review of the ~1300 Adverse Event Reports (ie., complaints), agency veterinarians established a set of criteria to select complaints for more detailed follow-up. The criteria were:

• Owner’s willingness to be contacted for additional information
• Type of symptoms reported (primarily gastrointestinal, hepatic and neurologic cases were selected)
• Time between the illness and submission of report (prioritizing recent illness)
•  Availability of veterinary medical records
•  Availability of product with lot number and best-by date

Out of the 1300 complaints received, 107 met all of the established criteria.

The follow-up

The FDA pursued one or more of the following avenues for each of the 107 complaints flagged for follow-up.

• Review of veterinary medical records
• Interview of pet owners about their pets’ medical and diet histories and other potential exposures
• Lab testing of pet food samples still in the pet owners’ possession, including tests for
  • Mycotoxins (aflatoxin, fumonisin, deoxynivalenol)
  • Excess vitamin D 
  • Bacteria (including Salmonella, E. coli, Listeria, Staphylococcus aureus)
  • Pesticides
  • Phosphine (a fumigant used to control insects on grain and other commodities)
  • Rancid fat 
  • Metals

In addition to tests carried out on samples obtained from pet owners, FDA collected 20 sealed product samples from retail settings, representing four brands of Purina pet food. These samples were subjected to the same battery of tests as listed above.

Finally, the FDA conducted a comprehensive Preventive Controls Surveillance Inspection at the Purina manufacturing facility in Clinton, Iowa, the manufacturing site of the most frequently mentioned products in the complaints. 

The lab findings

Lab tests did not reveal the presence of mycotoxins, pesticides, phosphine, rancid fat, excess vitamin D, pathogenic bacteria, or excessive heavy metals in any of the samples obtained from pet owners or from retail settings.

Bacillus cereus was found in 17 samples obtained from open packages of pet food collected from pet owners’ homes. Bacillus cereus is a common environmental contaminant, and genetic analysis of the 17 strains showed that they were unrelated to each other. None of the sealed packages of pet food contained Bacillus cereus.

Lab tests were conducted for the following metals and micronutrients: arsenic, cadmium, calcium, chromium, cobalt, copper, iron, lead, magnesium, manganese, mercury, molybdenum, phosphorus, potassium, selenium, sodium, sulfur, thallium and zinc. Findings for metals, including micronutrients, were not of clinical concern, meaning levels were likely too low to trigger animal illness in otherwise healthy pets, according to the FDA report.

The inspection

A team consisting of two FDA investigators and one inspector from the Iowa Department of Agriculture conducted a three-day inspection that began on April 30, 2024.

During the course of the inspection, the team reviewed the firm’s food safety plan, hazard analysis, GMPs, employee training, complaints, pest control, management interviews, and associated records. 

The visit did not include a physical inspection of the production plant. No environmental, in-process, or finished product samples were collected during the inspection.

At the end of the inspection, the FDA issued a Form 483, citing the company for not conducting a reanalysis of its food safety plan after having been notified by a representative of the FDA regarding complaints associated with a new potential hazard in pet food.

The plant manager claimed to have been unaware of the complaints/new potential hazard in the pet food they were manufacturing. He explained that complaints were handled at the corporate level. The corporate Director of Quality Assurance acknowledged having been made aware of the complaints. He stated that they had been working on the potential issue at the corporate level with their microbiologists and currently did not see it as a hazard.

The FDA’s conclusion (quoted verbatim)

After thoroughly analyzing pet food adverse event reports, testing opened products from pet owners and sealed products from retail settings, and conducting a facility inspection, the FDA has determined the existing evidence does not identify a public health concern that could explain the symptoms detailed in these adverse event reports about Purina pet foods. 

The agency followed standard processes in evaluating the adverse event reports and identifying those most likely to yield additional information. However, this situation did present unique challenges in that there was a large volume of reports describing a wide array of reported symptoms, but relatively few met the criteria for follow up. The agency is aware of various media outlets and bloggers that have reported a high number of adverse events. Unfortunately, the FDA did not receive data to fully evaluate or substantiate most of these cases. As a science-based regulatory and public health agency, the FDA relies on data to be able to analyze adverse events and identify causes of illness.

Throughout its analysis, the FDA had a conscious commitment to notify the public if it uncovered information, such as laboratory results indicating contamination or a specific illness in pets that ate a particular lot, that could translate into actionable advice for veterinarians or pet owners. The agency has previously issued safety advisories in situations when there was a common link between the reports, such as findings of a pathogen, vitamin overdose, or disease agent that connected the food to the illnesses. In the recent situation regarding the adverse event reports mentioning Purina pet food, there was no direct or consistent connection between the wide range of adverse events submitted to the FDA, and evidence does not conclusively link the reported adverse events to Purina pet food.

The FDA continues to monitor and evaluate pet food adverse event reports to identify potential follow-up actions. The agency encourages consumers and veterinarians to submit reports about issues with pet food electronically through the Safety Reporting Portal or by calling an FDA Consumer Complaint Coordinator. For additional support with using the online Safety Reporting Portal, the FDA now offers the SmartHub – Safety Intake Portal, where an electronic assistant helps walk individuals through the process of submitting their report. For an explanation of the information and level of detail that would be helpful to include in a report to the FDA, please see How to Report a Pet Food Complaint.

“A complete and compelling account of the hidden and not-so-hidden ways the food we give our beloved pets can be contaminated.” – JoNel Aleccia, Health Reporter, Food & Nutrition, The Associated Press.

“An invaluable resource for busy pet owners” – Food Safety News

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