Aflatoxin — Another Potential Food Contaminant

Published Jul. 20, 2012

I’m sure you are all aware of the current recall of dog and cat foods that have been manufactured primarily at a Diamond Pet Food plant in Gaston, SC because of potential contamination with Salmonella infantis bacteria. This is the same processing plant that was involved in an outbreak of aflatoxicosis in 2005-2006 that led to the deaths of more than 100 dogs. While most owners have at least heard of Salmonella, the dangers associated with aflatoxin are not as well known.

Aflatoxin is a toxic byproduct produced mainly by Aspergillus fungi. Aspergillus lives in the soil around the world and grows on crops like corn, peanuts, rice, soybeans, wheat, and oats. Under hot and dry environmental conditions and/or when crops are otherwise stressed (e.g., by an infestation of large numbers of insects) the fungi that are living on the crops will produce aflatoxin. Contamination levels increase if crops are handled incorrectly after harvest or are stored under conditions that promote fungal growth.

Aflatoxins can have a variety of effects when they are ingested by animals. Liver failure is a frequent outcome, with many patients dying despite prompt diagnosis and aggressive treatment. Dogs that are suffering from liver failure typically have some or all of the following symptoms:

loss of appetite
yellow discoloration of the whites of the eyes and other tissues
vomiting that may contain blood
diarrhea that may contain frank blood or be dark and tarry
dark urine
fever
abnormal bleeding and bruising

Aflatoxins can also disrupt the immune system, damage the kidneys, cause cancer, and destroy red blood cells.

The 2005-2006 outbreak of aflatoxicosis in dogs was caused by contaminated corn. Corn products are routinely screened for aflatoxin prior to being included in pet foods, but in this case the Food and Drug Administration determined that the manufacturer did not adhere to its own testing guidelines. As a result, Diamond strengthened their monitoring program for incoming corn and started running additional tests for aflatoxin on their finished products.

To quickly identify potential cases of food-borne illnesses, veterinarians and regulatory officials need to know exactly what pets have been eating. Owners can usually identify the brand name of their dogs’ foods, but not other essential information like product dates and codes. This is just one of the reasons why I recommend that owners avoid removing food from its original packaging. If your pet’s food needs to be protected from the elements, vermin, or from inquisitive teeth and claws, place the entire bag within an appropriately sized storage container. Hopefully you’ll never need the detailed product information provided on the label but, if you do, at least you’ll know where to find it.