In Asia nowadays, people are scared of taking in dairy products or anything that has milk in it, especially if it's from China. News are flashed on the television informing us about the pull-out of Chinese-imported products that contain milk or that it causes kidney stones in children but they never tell us, their viewers, what the hell "melamine" is about. Questions kept sprouting in my class which I try to answer as patiently as I could, though they are totally unrelated to my lecture for the day: How does melamine get in the milk? What is melamine's real use? How does it cause kidney stones? Does it affect adult kidneys too?
Literature in the textbooks and journals are not really that helpful because they are not for laymen. People with very little understanding of scientific terms will have kidney stones before they could ever decipher what the article was all about...so I'll try and explain it as simple as possible.
Before it was identified as a "bad guy" in the news, let me tell you what it was before all the media attention. Melamine is classified as a very heat resistant resin. If you have those microwaveable plastic bowls, these have been coated with melamine to prevent melting of the plastic when microwave particles pass through it to heat food. In fact, they are sometimes found in flame retardants! Melamine is also used to coat counter tops and white boards - see their glossy surface? That is melamine. Sometimes, it's found in glue (the ones that say that do not produce noxious fumes) and of course, burn proof fabrics like aprons and pot holders. Its derivatives from arsenic is used to treat African trypanosomiasis - therefore, an important chemotherapeutic agent.
Its usefulness was exploited in the late 1950's when it was patented as a non-protein nitrogen source for cattle but was turned down after several studies because it was difficult to digest and that urea and cottonseed would be better alternatives. You may ask, why do these cows need a nitrogen source? They need nitrogen to build protein. Their diet which is mainly grass, contain chlorophyll, a little nitrogen and many fiber. To become economically beneficial, they need to have more muscle. More muscle means more meat. The heavier they will be, the more money they will fetch for their owners.
Melamine manufacturers were not disheartened. They incorporated melamine in food products (like those that contain milk!) to increase their advertised protein content without really spending much on a natural protein source. Its very convenient for food products to claim protein contents since the tests used aren't specific for what kind of protein is being claimed in the nutrition label. Now, the plot thickens...how in the world do these food manufacturers add an insoluble substance like melamine in milk? They mix it with formaldehyde...which will also lengthen the storage period of their product.
Let's not get scared yet. Melamine is not really toxic...in low doses. In fact, it's lethal dose is less than 3grams per kilogram (based on rats). So if you're 60 kilograms, it would take 180 grams of melamine to kill you...and that's quite a lot. Besides, melamine alone will not kill you. Its combination with cyanuric acid will.
(Cough!) WHAT IS CYANURIC ACID?!
Cyanuric acid is an ingredient of some bleaches, disinfectants and herbicides. Sometimes, this is found in drinking water especially in heavily herbicide-bombed areas. There was a study conducted that cyanuric acid is also as toxic as melamine when alone. However, when combined with melamine, they cause major damage like the fatal kidney/bladder stones in children. These may lead to bladder cancer or worse, reproductive problems.
Let me clarify that today's melamine scare affected children because they're the ones that usually feed on milk. Although it is not stated in the literature that I've read, adult kidneys are prone to melamine cyanurate (the compound formed from cyanuric acid and melamine) because these developed kidneys are more prone to abuse like alcohol ingestion and of course accessibility to high protein diets (think Atkins's diet, steaks and protein shakes). Children have lower body mass so acute melamine toxicity is easier observed in them. Maybe it'll take me 5 more packs of soft chewy chinese White Rabbit candies before I experience this.
How does melamine get into Chinese milk? I have three (3) possible theories:
1. It's ingested by the cows themselves. Maybe there are unscrupulous herders that add melamine to cattle feed in hopes of increasing the nitrogen content in their diets. Cats die of renal failure by ingesting melamine..what more of cows, which are bigger than they are? Before they die, their milk may have been transported halfway across the world.
2. It may have been added in the milk to increase its protein content. They might have dissolved a little melamine in formaldehyde, then added it to the milk before being analyzed. It's like hitting 2 birds with 1 stone. Longer storage and higher protein means more profits.
3. It might have been in the container. Melamine has been used in fire-proofing or for making smoother surfaces, it is possible.
I hope our BFAD recalls all the milk products from our supermarkets, especially if they're from China. How do we protect ourselves while these melamine issue isn't resolved? Simple. Beware of anything dairy that is from China - that includes their chocolates, candies, cakes, cookies, biscuits, milk and anything that could possibly contain milk. Next, ask yourself if the protein content in a particular product has logical amount of protein. For example, if none of the ingredients in your bag chips naturally contains protein and the nutrition labels says it has protein...don't buy it! Lastly, eat fresh food that is locally grown. Like buying fresh carabao milk from your local farmers or from people who are into organic farming. It'll do the local economy some good and it will definitely keep your kidneys safe.
