Pet Food CSI: Deconstructing the recall

In more wonky news, an interesting article in Chemical & Engineering News was just released last week. (Shut up. I like science journals.)



It contains a pretty good comprehensive timeline of last year's pet food recall, with a focus on the scientific detective work that finally led to the identification of the contaminants responsible for so much animal sickness and death:

FDA, which regulates the manufacture and distribution of animal food and drugs, logged more than 18,000 phone calls after the recalls were announced. "This was the largest recall in FDA history," says Tolleson, who works in the agency's National Center for Toxicological Research (NCTR) in Jefferson, Ark. "There were more calls to FDA over this issue than anything we've ever handled before."

They peg the number of dead animals at "as many as 1,000," relying on the survey information released by the American Association of Veterinary Laboratory Diagnosticians. However, that survey is not complete, nor was it designed to elicit any kind of final or total number of dead pets. The actual number is undoubtedly much larger, based on numbers from the Veterinary Information Network, Banfield the Pet Hospital, and our own database. However, it's still much more accurate than the 12-14 we used to see so much of.



The article goes on to recap the 2004 recall (which we covered here) that turns out to have been an earlier melamine-related incident, although blamed at the time on mycotoxins.

Sadly, the 2007 incidents might not have been the first. A 2004 outbreak of kidney failure that reportedly struck thousands of dogs and cats in Asia originally was attributed to contamination of pet food ingredients by fungal toxins. But University of Georgia veterinary pathologist Cathy A. Brown and colleagues reported in September 2007 that they had found "compelling evidence" in tissue samples from autopsies of affected pets that both outbreaks were caused by the same toxic chemical combination (J. Vet. Diagn. Invest. 2007, 19, 525).

In the "Pet Food CSI" department, the article discusses some of the science used to identify melamine and cyanuric acid in the foods, and the distinguishing crystals they form in dogs' and cats' kidneys:

On March 30, FDA and Cornell University—whose animal health experts had been enlisted in the investigation by Menu Foods—announced that they had independently identified melamine as a contaminant.



[....]



The finding was a bit mysterious because the small amount of information available in the scientific literature indicated that melamine wasn't particularly toxic.



FCC staff next examined samples of the suspect wheat protein concentrate under a light microscope and separated out what appeared to be foreign particles. Fourier transform infrared and Raman spectra of the particles, as well as DART and GC-MS, confirmed the presence of melamine. FCC's analysis also unearthed further triazine contaminants, particularly cyanuric acid. [The FDA's R. Duane] Satzger says that total adulterant levels in the protein concentrate ran as high as 25% by weight.

Why was tracking down the contaminants so difficult?

The DART technique is much quicker than GC-MS because it requires no sample preparation, Satzger notes, but it depends on expensive equipment that's not widely available. Throughout April 2007, FCC scientists labored to develop a GC-MS method to rapidly screen pet food samples—one that could be replicated in other labs across the country with commonly available instrumentation. One challenge involved finding a way to test for multiple triazines, which have widely varying solubilities, in a single run. FCC researchers working in collaboration with FDA's Pacific Regional Laboratory Northwest, in Bothell, Wash., found that a solvent system of acetonitrile, water, and diethylamine did the trick.



During this same period, other FCC scientists were examining crystals from kidney tissue provided by FDA's Rockville, Md.-based Center for Veterinary Medicine, Satzger says. Raman mapping studies indicated the crystals could be melamine cyanurate. Lab tests also showed that mixing melamine and cyanuric acid in water forms melamine cyanurate crystals.



Meanwhile, Tolleson was gathering data about the toxicity of the pet food contaminants using cultured cells from the immune system known as macrophages. He found that cyanuric acid by itself was only slightly toxic; by contrast, melamine and the combination of both compounds were toxic to the macrophages.

I tried to elicit a comment from Procter & Gamble for an earlier story of my own, and somewhat surprisingly got a very polite " no comment." The article gives a hint as to a possible reason:

In April 2007, Procter & Gamble toxicologist George P. Daston showed that the triazine compounds are deadly to rats when consumed in combination, Tolleson says. Rats that ate the mixture developed the same kidney disorder seen in pet cats and dogs. Neither Daston nor other P&G representatives would comment for this story because the company is involved in ongoing litigation associated with the contaminated pet food.

Regardless, the forensic scientific work continued, broadening our understanding of just what happened when these compounds were consumed in large amounts by pets:

In November 2007, University of California, Davis, veterinary toxicologist Birgit Puschner and colleagues reported on the results of feeding melamine and cyanuric acid individually and in combination to a few cats (J. Vet. Diagn. Invest. 2007, 19, 616). The researchers found that a single 32 mg/kg dose of the combination can cause acute renal failure in cats. Puschner suggested that the compounds cause renal damage at least in part through precipitation of melamine cyanurate crystals out of acidic urine in the kidneys.



"That pretty much brought the story full circle," Tolleson says. "Melamine cyanurate was present in the contaminated raw material, it was detected in the crystals that were responsible for kidney failure, and feeding animals with melamine cyanurate reproduced the kidney toxicity."

That's where the science is today; now it's time to follow the money.

While the technical studies continue, the legal and financial mess spawned by the pet food adulteration is also gradually unfolding. This February, a federal grand jury in the U.S. indicted ChemNutra and its owners; Xuzhou Anying Biologic Technology Development Co. and its Chinese owner; and the export broker Suzhou Textiles, Silk, Light Industrial Products, Arts & Crafts (SSC) and its Chinese president for their roles in the contamination scheme. SSC had obtained the contaminated wheat from Xuzhou Anying on behalf of ChemNutra. According to the indictment, the shipments were falsely labeled to avoid inspection in China. ChemNutra's owners reportedly deny the allegations involving their company.



Menu Foods' Henderson says it's unlikely that customers of the Chinese companies will be able to obtain restitution because they have been shut down (C&EN, July 30, 2007, page 31). However, his firm has sued ChemNutra. Menu Foods itself faces considerable liability. The recall cost the company $54 million. Furthermore, on April 1, 2008, Menu Foods announced it had reached a tentative mediated settlement with pet owners who had filed claims against the company. A court hearing is scheduled for May 14.

The full article is here.

Comments

[slt]

I was just thumbing through Chemicl & Engineering News last night but I nodded off...



; )



Just curious if any mention was made regarding the rat poison finding or the differing stories between Pedigree saying "We told everyone right away" about the link to the 2004 deaths and (almost) everyone saying "Nuh-uh"?

[Dorene]

More science journal article blogging! Who needs an abstract when we have Christie! :-D

[Janeen]

More oversight of the pet food industry is desperately needed. The melamine fiasco is just one piece of the story. We recently reported on the increasing number of Streptococcus infections in pets -- and humans -- arising from contaminated pet food.



http://smartdogs.wordpress.com/2008/05/13/pet-food-pork-and-tampons/



Add in recent problems with salmonella, botulism, clostridium - and ingredients made from 4D animals... and we have a problem of nearly epidemic proportions.

[Gina Spadafori]

Pet food? Sure, but ... more oversight of the ENTIRE FOOD INDUSTRY is desperately needed. I gotta say our covering of the pet-food recall, food-safety issues and the FDA has turned me into a person who sources almost everything edible that comes into my house.



If I don't know/can't find the source, I mostly do without.



And of course, I'm now moving in to growing as much for myself as I can, as well as buying from the local CSA for additional neighborhood grown food. (My CSA is just a couple miles away, and our season's food boxes start this Friday, yay!)

[Colorado Transplant]

At www.blogs.wsj.com/health/ today there is an article about Stupak asking the FDA boss if he would like more subpoena power--the boss said it would be helpful.



Maybe it will happen next year.



Also, I have heard (I am not sure where) that the head of the FDA asks Congress for more money, especially for inspecting imported food, and Congress voted it down. One congressman said that the FDA should do more with less.



Again, maybe it will happen next year.

[Gina Spadafori]

MSNBC.com has a front page story about the surge of interest in "Buying American."



The beginning:



"It started with the tainted pet food."



Story here.



The story also talks about the Web site, How Americans Can Buy American.

[Colorado Transplant]

Many years ago I was surprised when a few items were "Made in China"



Now, "Made in America" label or printing is what amazes my brain.



I enjoyed the story about the woman trying to buy all American goods.

[Gina Spadafori]

Yep. Times change, sometimes for the better, but too often not!



I couldn't believe how hard a time I had finding clothespins that weren't made in China! (I'm putting out my wash sometimes now, part of my "Year of Living Greenly" effort.

[slt]

You're hanging your wash out? Every dog in my house just asked if they could come over to your "amusement park"!

[slt]

E. coli scare prompts beef recall in 11 states



"The meat being recalled is used in ground beef products. Included are 30-pound and 60-pound boxes and 47-gallon barrels of "MORREALE MEAT" beef products."



"The states affected are Florida, Georgia, Indiana, Iowa, Massachusetts, Michigan, Illinois, Nebraska, Pennsylvania and Wisconsin."



full story at http://www.cnn.com/2008/US/05/18/meat.recall.ap/

[JuliaMartin]

WHAT??!!, there are still recalls? I thought "recall" had been "RETIRED" in favor of

"voluntary product withdrawal" or "stealth recall" or "reformulated improved poison" or just "all new, all natural" advertising supporting a new package design.





What the heck is wrong with the meat industry?

They can kill just as many people with tainted goods as the pet food industry kills,and get away with it, just like the pet food industry did, they just need to use the FDA cover up system and keep lying about the death toll, very simple. Very effective.



Since any number of illnesses or deaths of humans or pets can be, and are, routinely lied about by the FDA, I fail to see the problem.



This beef recall won't kill enough people to matter. Or change a thing. And better get used to it, no number of dead pets is ever going to matter, or change a thing.

Several hundred thousand dead pets in 2004 did not matter. 300 thousand dead pets in 2007 and over half a million suffering damage did not matter and I tremble at the death toll it is going to take to make it matter.



Over a million dead pets, left to rot in full view, might do it. Or a few dead kids that snack on a handful of euthanasia brand kibble.

Whichever comes first.

[Colorado Transplant]

Geez, why did they leave out Colorado in the recall. The docs here could shore up their practices with all the people who get sick from tainted, should have been withdrawn, beef.



I guess they didn't send any of that stuff here.

Mama mia, my cats can have the beef for now!

[Dorene]

Gina --



Remember, "reuse" is just as "green' as "buying American new" -- I bet you could get some great clothespins at a local thrift store.



The Goodwill store and the local hospital thrift store are my first stops for "basics" -- if they don't have what I need, them I move on to "buying new."

[Gina Spadafori]

Great thought, and that didn't even occur to me. I'm going to remember to check out the second-hand stores ... and craig's list, too. Also Freecycle!

[Cathy Z.]

Thanks agian, Christie, for the wonderful article.

[Bernard J. (Bernie) Starzewski]

25% by weight?



Let me repeat that for effect...



25 percent by weight!



I said at the time that this was NOT a simple contamination event which was the word being pushed at the time. Search up the old blogs if you want to check on my posts but that is what I said.



25% by weight or 25% by volume is not some floor sweeping Janitory accidentally "contaminating" a batch. 25% is willful substitution of chemical crap for food.



It was an out and out substitution of product because thats what Anying made and that is what they advertized and that is what they sold and that is what they delivered.



It is after all called "Chem" Nutra. What part about "Chem" do we not understand?



NPN, Nadine. That's what you posted and thats what I zeroed in on and that is what this stuff is. Non Protien Nitrogen. And that is what killed my Brandy.



No, this was no accident. It was pure lousey stinking greed.



I think that it is appropriate here in a dog blog that I attribute the this word to the people at Chem Nutra and Menu Foods...



BASTARDS!