Almost exactly a year later. Huh.

By Harbin (Own work) [Public domain], via Wikimedia Commons
A recent bit of investigative journalism/adulteration fishing conducted by WJLA in Washington D.C. found Pentobarbital consistently in one particular brand of pet food after a total of 62 samples were submitted for presence/absence testing.

In total, we tested 15 cans of [brand]. Nine cans — 60-percent of the sample — were positive for pentobarbital. And while the levels detected were not lethal, under federal law they are also not permitted at any concentration.

Neither FDA nor the company wanted anything to do with making a statement (rightfully so when you are presented such information from a random organization without your own investigation), but I’m sure will in the next few days. As of today no recall has been posted for the affected brand.

And while the levels detected were not lethal, under federal law they are also not permitted at any concentration.

This is true, but one of my biggest issues during the recall/illnesses last year was that FDA had never (before the recall) explicitly defined a zero tolerance rule for this particular material, and had a study which indicated that there was a threshold in which no expected adverse events were anticipated in even the worst case scenario for exposure. This met the criteria for the adulteration definition:

A food shall be deemed to be adulterated – If it bears or contains any poisonous or deleterious substance which may render it injurious to health; but in case the substance is not an added substance such food shall not be considered adulterated under this clause if the quantity of such substance in such food does not ordinarily render it injurious to health.

FDA determined in their study that dogs consuming less than 50 micrograms of pentobarbital per day had no-observable-effects compared to controls, and based on that study concluded that it was highly unlikely that a dog consuming dry food with the observed levels of pentobarbitol observed (up to 32 ppb) will experience any adverse events. While not regulated, this certainly was considered to be good scientific data to support a threshold, and at no point in the study did FDA describe a zero tolerance legality for the chemical.

Since my post last february, FDA released a Q&A about the original recall, which made it abundantly clear to all other pet food manufacturers their position on detectable levels of pentobarbital.

There is currently no set tolerance for pentobarbital in pet food and its detection renders the product adulterated.

Hey, FDA. Props. Thank you for making your position clear here. They even repeat it several times throughout the Q&A. What about that study though?

Nineteen years ago, the FDA collected dry dog food samples to determine whether products contained pentobarbital. The sampling was not representative of the entire pet food market because the sample collectors specifically sought out dry dog foods with certain animal-derived ingredients. The sampling method and the age of the data generated by the survey means that the data cannot be used to draw inferences about dog food being produced and sold in the U.S. today.

…it wasn’t representative of the total market, okay. I can work with that. But the safety conclusions of that study didn’t have anything to do with the market presence…what about the observable-effects dose? FDA dodges the question by explicitly stating what the study did, but addressing none of the implications of the conclusions written in 2002.

FDA hammered it home again when they released the guidance for Animal Food Preventive Controls by identifying pentobarbital as a reasonably foreseeable hazard…but then I hit another snag. You see, the Q&A for the previous recall stated:

 It is not acceptable to use animals euthanized with a chemical substance in pet or other animal foods. FDA’s understanding is that animal protein ingredient suppliers typically implement practices at their facilities to ensure that euthanized animals are either not accepted at the facility, or are segregated from animal protein going for animal food use.

Which matches the adulteration definitions mentioned above. However, the preventive controls guidance considers pentobarbital a reasonably foreseeable hazard because:

Pentobarbital residues should be identified as a known or reasonably foreseeable hazard for facilities that salvage skeletal muscle, organs, or other tissues from animals that died other than by slaughter if the cause of death is unknown, or the animal was known to be euthanized with chemicals. The salvaged skeletal muscle, organs or other tissues are generally used for food for carnivorous animals such as those at zoos, wildlife rehabilitation centers, private wildlife preservation centers, alligator farms, mink farms, or in pet food products. We recommend operations that salvage skeletal muscles, organs, or other tissues for processing determine whether animals have been euthanized using pentobarbital and, if so, exclude those animals from use as animal food. 

In a guidance document the “recommend”…that is not strong enough language, the FDCA states that animal food or components thereof is adulterated if “it is, in whole or in part, the product of a diseased animal or of an animal which has died otherwise than by slaughter”. This isn’t a recommend, it’s a legal requirement.

But that just means it’s the law. FDA doesn’t have to enforce the law, and in fact is an interpretation agency as well. Compliance policy guide Sec. 675.400 states:

The Center for Veterinary Medicine does not believe that Congress intended the Act to preclude application of different standards to human and animal foods under Section 402. Different standards have historically existed for human and animal food concerned with aesthetics….Policy: No regulatory action will be considered for animal feed ingredients resulting from the ordinary rendering process of industry, including those using animals which have died otherwise than by slaughter, provided they are not otherwise in violation of the law.Rendered animal feed ingredients which contain harmful microorganisms, toxins or chemical substances may be considered adulterated under Section 402(a)(1) or (2) of the Act.

So FDA threw out the “animal which has died otherwise than by slaughter” provision of the adulteration definition, but still left a clarifying statement that if a toxin or other substance survives rendering it still makes the product adulterated, as is the case with pentobarbital.

Ultimately, the entire surfacing of pentobarbital as an adulterant in pet foods is a reminder that all guidance is binding on industry in practice but it confers no assurance that FDA will stand by any of the material. Even the Defect Levels Handbook, which includes maximum levels of natural or unavoidable defects in foods for human use that present no health hazards are guidance only, and are thrown out the door  in the event a product is associated with a problem (note, this is a GOOD reason to do so) or FDA decides that it shouldn’t apply in that situation, based solely on the opinion of the inspector.

Evidence indicating that such a violation exists causes the food to be adulterated within the meaning of the act, even though the amounts of natural or unavoidable defects are lower than the currently established defect action levels.

So, until it ends up in the code of federal regulations or otherwise in a congressional bill, if it’s poisonous or deleterious to health in any concentration, be prepared to consider it adulterated. As far as how to consider what substances apply…it’s complicated and it depends. Everything is safe until it’s not.