Rare but well-publicized events have occurred in which a pet food was implicated in a pet’s illness or death or a pet owner became ill because they handled a contaminated pet food product or treat.


Melamine Contamination

Without a doubt, the 2007 melamine contamination is one of the most widely publicized cases where something went wrong with pet food. What was supposed to be wheat gluten and rice protein concentrate sourced from China was intentionally adulterated with non-food material. This produced a far less expensive ingredient and gave the sellers a larger profit margin. The adulterated ingredients slipped through checks because they appeared genuine when screened by routine tests despite containing an illegal substance. In short, the manufacturer committed the crime of “economic fraud.” While the manufacturers may have never intended to hurt animals, when the pet food companies used the ingredients in good faith, there were deadly results.

The types of ingredients in this case are traded primarily on the basis of crude protein content. Crude protein is the chemical method used to test the protein content, named because it does not directly measure protein, but a component (nitrogen) of the protein instead. Under normal circumstances, protein content is 6.25 times the level of nitrogen present in feed. This means the amount of protein can be calculated by the amount of nitrogen present.

Some non-protein sources of nitrogen are acceptable for use in ruminant feeds because ruminants (such as cattle, sheep and goats) convert them into protein through the bacteria in their gut.

But non-ruminant animals cannot do this.

Melamine and cyanuric acid contain non-protein nitrogen as a key part of their molecular structure.

Miniscule amounts of these compounds were introduced into the wheat or rice flour so crude protein analysis would show a protein content similar to that of wheat-gluten or rice-protein concentrate and could be labeled as such. These adulterated materials not only utilized non-protein nitrogen sources not approved for pets; they utilized non-protein sources forbidden in any animal feed. This manipulation is clearly an intentional act of adulteration.

An extended explanation of the 2007 melamine incident is further described on the U.S. Food and Drug Administration (FDA) website.


Salmonella infantis in pig ear chews

Salmonella, a group of bacteria, are a common source of food-borne illness in humans. In the 1990s, Salmonella infantis contaminated pig ears processed for pet chews in a Canadian slaughter facility and these products sickened several people.

At retailers, the chew products were in bulk displays accessible to both children and pets. Additionally, given how the products are used, there is a fairly high risk for humans (especially children) of infection.

Tracking the source was complicated. These chew products were seldom labeled with more information than “pig ears,” and little or no tracking information was included on the containers. Following the event, many distributors and retailers took measures to avoid similar incidents. They began requiring full tracking information for these products as well as individual wrappers to prevent contamination. They also distributed safe handling instructions at the point of sale.

Today’s visitors to the FDA website see more recalls for salmonella than in the past. This is not because of an increase in salmonella incidents—only that potential problems are being identified sooner. The FDA published a guidance for industry, and businesses are responding by catching problems much earlier to prevent pet and human illness.

A sensible pet owner always handles pet food and chews using safe food handling procedures and practices. If it is food for a pet, it is also food for insects, molds and bacteria. It should be kept clean, separate and away from children; food bowls should be washed frequently with hot, soapy water.



It is important to note that the FDA, states and AAFCO have emphasized the need for standardized process controls, and many pet food makers have, for some time, implemented such process controls for all their products.

Previously, the law required such measures only for livestock feeds incorporating drugs and for canned pet food products.

However, the aim of recently passed federal legislation, including the Food Safety Modernization Act (FSMA) and the Food and Drug Administration Amendments Act of 2007 (FDAAA), is to improve the safety of animal feed, including pet food, through a number of new standards, process controls and other features. Their aim is to prevent—rather than react—to animal feed incidents.