In March 2015, rumors appeared on social media that dog treat brand Canine Carry Outs (commonly misspelled as “Canine Carryouts”) contains anti-freeze under the “hidden” ingredient name of propylene glycol and is therefore dangerous to feed to dogs. Similar rumors circulated online about Canine Carry Outs before the claim migrated to Facebook in 2015 (one earlier Facebook version did not circulate as widely).
The Canine Carry Outs warning closely resembles a similar rumor about Purina’s Beneful brand pet food, which circulated in early 2015 as well. Although Beneful wasn’t mentioned in the Facebook warning shown above, it’s possible that the rumor stemmed in part from earlier alerts that mentioned other brands of dog foods in conjunction with propylene glycol.
It’s not precisely accurate to suggest that propylene glycol is a “hidden” ingredient and is therefore likely dangerous, as the Agency for Toxic Substances and Disease Registry (ATSDR) explains in a document about the substance’s use as a food additive:
Although propylene glycol is not approved for use in cat food, it is classed as generally recognized as safe for dogs in addition to humans. Purina’s response to Beneful rumors contained a longer answer to questions about propylene glycol in pet food:
Propylene glycol is quite different from ethylene glycol, the anti-freeze used in automobiles. Propylene glycol is approved as a food additive in human food and in feed for animals, except cats, in the U.S. and Canada.
Ethylene glycol — not propylene glycol — is the active compound in most automobile radiator anti-freeze solutions, and is toxic to animals and humans when ingested. Propylene glycol has a different molecular structure, giving it different properties and allowing it to be used safely in animal feed, except for cats, as well as in human foods, such as cake mixes, salad dressings, soft drinks, popcorn, food coloring, fat-free ice cream and sour cream.
Purina contrasted the oft-vilified ingredient with another form of “anti-freeze”:
A September 2012 version of the contaminated pet foods series of rumors (including Canine Carry Outs) listed several brands of pet treats [PDF] but did not include the number of complaints received (whether or not they were deemed to have merit). Canine Carry Outs was not among the brands named in those complaints.
The Facebook poster did not elaborate as to why she made the claim about Canine Carry Outs in her post, but one day later the brand was coincidentally acquired by the J.M. Smucker Company. It’s possible that news mentions of the Canine Carry Outs brand of jerky treats revived older rumors about their purported danger; however, we could find no credible reports of pet injury, death, or recalls linked to the brand despite long-circulating rumors about its safety.
“J. M. Smucker Completes Acquisition of Big Heart Pet Brands.”
The Huntsville Item. 25 March 2015.