But the debate over the toxin, and the concentration involved, reinforces my belief that the problem is biologic. If some poison got into the wheat, it would contaminate some products, then the poison would be diluted as more food was processed through the line. Unless someone continued to put the poison in the food, it would quickly go away. The first few batches of food would have lethal doses of poison, but as the food passed over the poison, it would take the poison with it.
This story involves thousands, or tens of thousands, of animals. Only something that can reproduce could contaminate that much food.
In some countries they use melamine monomer as a fertilizer- six nitrogen, three carbons and six hydrogens, a good source of nitrogen.
In the US we use ammonium nitrate, but some countries don't trust their citizens with stuff like that (we make about 6 million tons a year and so far only Karl Armstrong and Tim McVeigh have misbehaved).
China has been known to use melamine as a fertilizer and sometimes as a sort of pesticide.
Point is, melamine plastic and melamine monomer are different.
I think that some bags of fertilizer got mixed with bags of wheat and processed, or a tank car was used for fertilizer then wheat without cleaning.
Stand Back! I, gonzo, am a Certified Plastics Engineer, and I shall assuage your fears!
Melamine, or melamine-formaldehyde, or urea-formaldehyde - lotsa names here, because, well, it's real name has been sorta fudged over many year - is a thermoset plastic. That means you heat a pot of chemicals up, shape it like you want it, keep heating it until it's hard, and then cool it and use it. If you made a cup out of it, you got a cup! Have some coffee!
It is not toxic (remember the coffee?), but it does kinda stink when it's cut with a power saw. It's a speed/abrasion thing that breaks down the polymer chains, liberating some gas, like formaldehyde and others.
BTW, cups, saucers, bowls, and plates are made from the stuff. They called it 'Melmac'(Melmac-melamine: get it?), and it was once very popular as durable, non-rusting, outdoor, tableware. Some other uses are floor tiles, countertop covering (Formica-formaldehyde: pretty neat, huh?), and lots of other really handy stuff. Cheap Inexpensive, too (I HATE the word 'cheap' when it comes to plastics).
"How is it made, you ask?" Well, they take a bunch of chemicals, mostly liquids, put them in a big tank, and ... ah ... they just cook it, OK?
"Where do they get the chemicals, you ask?" Now, it gets interesting!
A dairy cow produces milk. It's a living machine that we feed grass and stuff to, and it makes gallons of milk! It also makes fecal matter which we use to describe dimocRATS, and in fact, they're the same thing! Then we call it fertilizer.
The cow also makes gallons of urine just standing there, while we're using the milk and poop. That 'urine' is a veritable cornucopia of hydrocarbon chemical compounds just waiting to be processed into something else.
Yes, that's right, boys and girls - Melamine, Melmac, Formica, etc., are all potentially made out of cow-piss! They can be made out of other things, but there's a lot of cow pee available out there, and if you really believe in recycling, this shouldn't bother you at all.
Now have a nice day ................... FRegards
PS: I have been waiting to tell that story for 30 years ...