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Food Safety Practices

Food Safety Practices Questioned

Reports of mortality in dogs and cats in the spring have led to serious questions about the safety of the U.S. food supply, and have implications for our own.

After sick pets came into U.S. vet clinics by the hundreds in March and April, the U.S. food safety watchdog, the Federal Drug Administration (FDA) began testing pet food samples.  Initially, an ingredient in rat poison (aminopterin) was suspected. But these initial test results could not be duplicated by several leading universities, and further inspection of feed ingredients revealed the true culprit: melamine.


Until April, melamine was certainly not a substance commonly known to feed manufacturers in North America.  It’s a toxic substance that when combined with formaldehyde forms a plastic resin.  It’s a metabolite of cyromazine, a pesticide, and it’s also used as a flame retardant.

So how did such an obvious non-food ingredient end up in pet food? Investigations revealed that imported wheat and rice gluten from China, used as a thickener in semi-solid and wet pet foods, was the source. Although China has a notoriously lax food and feed
production industry with minimal government supervision, the FDA accepted the labelling and quality of the imported gluten products.
It avoided detection because the protein content seemed to be what it should.  Problem is, our common method for testing protein levels, called the Kjedahl nitrogen assay, only measures nitrogen, which is present in higher amounts in protein than in carbohydrates.

It doesn’t measure true proteins. Melamine is 66 per cent nitrogen. It’s thus effective at boosting nitrogen levels, skewing protein testing.

And that’s why the Chinese manufacturers added it to the gluten.  According to some press reports, this is a common practice in that country for livestock feeds.

But what I find disturbing is that after the problem was identified, a large proportion of the pet food was not destroyed.  Instead, it was fed to pigs and poultry in the U.S., deliberately introduced into the human food chain. 

Apparently it is OK to eat animals that have been fed melamine. Both the FDA and Health Canada agree on this.  They claim to have performed ‘health risk assessments’ and have determined the human risk to be low.

How do they know this?  Test results are non-existent and information released by both agencies has been extremely vague.  It’s true that dogs and cats were exposed to much higher levels of melamine, but questions still loom.  Fact is, we don’t really know how this substance acts in an animal’s body, or how it acts with other ingested substances – what level is truly safe. 

Unfortunately, the pet food industry in North America is not regulated as heavily as it is for livestock, but after this crisis that will certainly change.  But the practice of feeding waste and byproducts and vegetable proteins to livestock needs re-evaluation. Livestock shouldn’t be garbage cans for other industries. 

Hopefully this incident will spur some discussion and real actions on food safety, and maintain consumer confidence. I don’t think it’s appropriate to tell consumers that their food is safe when it will likely kill their dog.   n

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