Is the burgeoning pet food recall and animal feed contamination scandal the result of a "perfect storm" of relaxation of regulatory standards, food industry complacency in relying on outdated tests for detecting adulterants and Chinese productivity in ramping up the productive capacity of an industrial chemical to the point where it could be cheaply used to inflate the sales value of some common food additives?
And are we only in the eye of the storm now, awaiting word that not only has melamine entered the human food supply indirectly via contaminated animal feed but also may have been being added directly to human food products since as long ago as 2005 or earlier?
Answers after the jump.
Elsewhere, there are informative diaries relating the current events in the pet food recall situation (search on tag=pet food recall). In this diary, I want to focus on what I have been able to learn about protein testing in the food industry and the motivations that Chinese manufacturers (and others) might have for adding melamine to increase protein content in such ingredients as wheat gluten, rice protein, corn protein and soy protein to suggest how systemic and longstanding the problem might be.
There is a report on a Chinese supplier's website of PSEUDO rice protein containing non-protein nitrogen (possibly melamine) for sale in the marketplace dating back to 2005:
BE CAREFUL OF PSEUDO RICE PROTEIN FEED GRADE
Recently, we found Rice Protein Concentrate Feed Grade with very low price in market. Its appearance is White, good fineness & good looking. It make some of our customers confused about our Rice Protein's appearance and price.
After we searched in the market, we kindly inform everybody,
This kind of product is PSEUDO rice protein, and there are 2 kinds:
1. Inorganic nitrogen and a small part of other vegetable protein mixed together.
2. Biuret (one of the carbamide/urea)
How to know it is PSEUDO RICE PROTEIN: (Based on analysis)
1. Total Nitrogen is Inorganic nitrogen.
2. All proteins have isoelectric point. It has no isoelectric point (pI).
One thing to notice from this report is that there were two kinds of fake or adulterated protein concentrates. One kind contained urea (aka carbamide) which would not be anything particularly new, as I relate below. However, the other kind contained some other non-protein nitrogen source.
At this point, it may be worth noting that melamine production capacity has increased greatly in China in recent years leading to surplus availability:
The capacity of melamine in the world has made a rapid increase in recent years. There were more than 90 melamine producers in the world in 2004 with a total capacity of 1.4 million t/a and an output of around 1.2 million tons, an increase of 5% over the previous year.
China had more than 70 melamine producers in 2004 and the output reached 260 000 tons, an increase of 13% over the previous year and accounting for around 21% of the world total. The export amount was 73 000 tons. The export was mainly made to Europe, America, Japan, Korea and Southeast Asia.
It is expected that the output of melamine in China can reach 300 000 tons in 2005 and the export amount will be 90 000 tons.
It is clear that China has many legitimate uses for the melamine it has been producing (e.g., in timber processing, plastic, coatings, papermaking, adhesive, textile, leather, electric, pharmaceutical, flame-retarding agent and rubber antioxidant industries). The major significance of the great increase in their production capacity (and actual production) is that they seem to have created a melamine surplus leading to very inexpensive melamine being readily available on the market.
Protein concentrates are graded and priced largely on the basis of crude protein content. Proteins, unlike most other legitimate food components, contain nitrogen, making nitrogen measurement a common surrogate for protein content. The standard tests for crude protein content used in the food industry (Kjeldahl and Dumas are the ISO standards) measure total nitrogen and would, thus, be fooled by the addition of non-protein nitrogen. Not surprisingly, it has not been unknown in the protein meal industry for unscrupulous manufacturers to add urea (a common and inexpensive source of non-protein nitrogen) to protein meal to increase its apparent protein content (in fact, this is allowed to some extent in feed for ruminants, e.g. cows, which can digest urea). For instance, in the soybean meal industry, it is recommended that purchasers conduct qualitative tests for urea in protein meals originating from Southeast Asia:
Since the early 1970s, the feed industry in Southeast Asia has made tremendous expansion. High quality materials especially protein meals (fish meal and soybean meal) are often in short supply and also exhibit a variation in the quality aspects of nutrient availability. Since protein sources especially fish meal and soybean meal generally have high unit cost, the company must establish written ingredient quality standards for purchasing, but the methods for examining the physical qualities, especially for foreign materials and evidence of mold, must be fast, accurate and practical by the operators at the receiving plant.
...
Quick Test for Urea (Qualitative Test)
Reagents:
Urease solution: 0.2 g urease stir into 10 ml H2O.
Bromothymol blue solution: Rub 0.15 g Bromothymol blue in mortar with 2.4 ml 0.1 N NaOH, wash mortar and pestle with H2O and dil. To 50 ml H2O.
Test paper A: Mix 10 ml urease solution 1 and 10 ml indicator soln. 2. Pour mixture into watch glass, dip pieces of filter paper (Whatman No. 5) in soln. And hang paper to dry. Store dry paper (Orange color) in well-stoppered dark glass bottle in a cool place.
Test paper B: Dilute indicator soln. 2 with equal portion with H2O. Dip pieces of filter paper (same kind used for test paper A) in indicator soln. And hang to dry as in 3.
Procedure:
Stir 2-3 g of test sample in 50 ml H2O and let it stand for 2-3 min.
Placing 2-3 drops of test sample on dry test paper A, the appearance of blue or green spot after a few minutes of incubation at room temperature indicates urea.
For detection of urea in a very small, dry particle, dip both test paper A and B H2O and then shake the papers to remove excess H2O by using clean tweezers. Place the papers on a clean flat piece of glass. Place the sample on the papers and cover with another clean flat piece of glass by pressing down gently. Blue spots on the test paper A indicate urea (30-60 sec.). Spots continue to develop and enlarge for 10-20 min. and then fade gradually. Time varies inversely with urea concentration. If blue spots develop on both paper A and B, this indicates alkaline particles.
Unlike urea, melamine is hard to detect in common tests.
One objection that has been raised to the theory that melamine was added deliberately has been that since melamine is mostly derived from urea, it would just be cheaper to add the urea directly. However, as melamine contains a higher percentage of nitrogen than urea, being able to raise nitrogen levels with less adulterant may make processing the urea to melamine cost effective and might also have the benefit of making it less detectable by quality control tests as less melamine than urea need be mixed into the product. Another point is that melamine "scrap" may be cheaply available. As the New York Times reported, the Chinese supplier that supplied the first tainted wheat gluten had been trying to buy "melamine scrap" in online sites. Combine the Chinese melamine surplus with the ability of melamine to defeat the common qualitative quality control tests for urea conducted by purchasers and you have a recipe for creating an economic incentive to adulterate protein meals with melamine rather than urea since at least as long ago as 2005.
The risks of ingesting large amounts of melamine over long periods of time by humans or other mammals is not particularly well understood and researchers are still trying to figure out the mechanisms by which it may have resulted in renal failure in pets. Chinese suppliers may very well not have realized that they were actually "poisoning" animals or people. In the case of urea contamination, for example, as urea is a naturally occurring waste product excreted in urine, non-ruminant mammals can tolerate fairly high doses. The Chinese suppliers of melamine-adulterated products may have believed that melamine was, similarly, not particularly harmful given the limited literature and were "just" trying to make more money. They may have been being unscrupulous and reckless, but they would probably have wanted to keep the repeat business of purchasers. The intent here was likely not to cause harm but the intentional adulteration of food additives with chemicals not approved for animal or human consumption strikes me as the sort of willful recklessness that serves as intent in criminal manslaughter actions. Sadly, such "food fraud" is rampant in China.
This is not meant to be a "bash China" diary, however. While all the identified tainted food so far has originated in China, other suppliers are operating under the same economic incentives and there may be problems elsewhere, too. Moreover, the only somewhat responsible action I have found any company to take early on in this situation was that 2005 warning a Chinese manufacturer placed on its website. To the extent that the market can police a problem ahead of time, that was it; a supplier, not wanting to lose sales, warned its customers of lower-priced fraudulent products for sale in the marketplace.
I am most outraged, however, that I was able to find that 2005 warning in English on a Chinese supplier’s website and no evidence that anyone else in the export, import or pet food manufacturing industries or any regulatory authorities took any other steps to inform purchasers that additional testing would be required to detect the contaminants. This supplier should have (and may have) done more to notify purchasers and regulators. But, in any event, companies that import these products should have been able to locate this warning easily enough and contact each other and institute new quality control tests to screen for other potential non-protein nitrogen adulterants.
Now add in the facts that only now is FDA conducting any testing for melamine in imported protein concentrates and that the government may have helped signal its lack of concern with melamine contamination in 1999 ("EPA also proposes to remove melamine, a metabolite of cyromazine from the tolerance expression since it is no longer considered a residue of concern"), and you have a "perfect storm" for wide-scale protein concentrate adulteration.
And we may not have seen the worst of it, yet. In addition to now testing a wide variety of imported food products and ingredients for melamine contamination, FDA has also
asked the Centers for Disease Control and Prevention to use its surveillance network to monitor for signs of human illness, such as increased renal failure, that could indicate contamination of the human food supply.
While I'm mixing movie metaphors here, as in the China Syndrome, we may be heading for a meltdown.
What steps can you take to ensure the food safety of yourself and your loved ones, including your pets? As is usual with such large scale problems, personal, political, legal and economic pressure may all be needed. Personally, I am no longer feeding my cats any products containing any wheat gluten, rice protein, corn gluten, corn meal, soy protein, rice bran and am eliminating these ingredients from my diet, as well. I leave it to you in the comments to recommend other steps we can all choose among. I do recommend staying informed. I have found Itchmo and Pet Connection to be two blogs with much more up-to-date information than the FDA's official recall web page. I'll also close with one plea: If you have the financial resources, consider making a special donation to your local or other needy animal shelter. They have been hit particularly hard by all the pet food recalls.
Update: China Bans Melamine in Food Products
Update II: For more on the failures of the regulatory systems in this and other food crises, see Deep Harm's excellent What are food safety officials hiding?