The U.S. Food and Drug Administration is expanding a dog-food recall of certain products from multiple brands that may contain an unsafe level of a toxin called aflatoxin. Aflatoxin is a byproduct of a type of mold (Aspergillus flavus) that can grow on grains commonly used in pet food, according to the FDA. When pets consume too much aflatoxin, it can cause sickness and, in some severe cases, longterm liver issues and/or death.