When I first heard about this melamine crisis I was a little confused since I was pretty sure melamine was the thing they made melmac plates out of. I used to collect and sell those on eBay many years ago.
I looked into it further and and this article is a good one, though it has not been updated to reflect the current crisis.
What exactly is melamine?
Melamine is an organic compound that is often combined with formaldehyde to produce melamine resin, a synthetic polymer which is fire resistant and heat tolerant. Melamine resin is a very versatile material with a highly stable structure. Uses for melamine include whiteboards, floor tiles, kitchenware, fire retardant fabrics, and commercial filters. Melamine can be easily molded while warm, but will set into a fixed form. This property makes it ideally suited to certain industrial applications.
Melamine resin is manufactured by mixing urea with formaldehyde under heat and pressure. The substances begin to polymerize and are forced into a mold which will create the desired shape. Under pressure, melamine releases water, which could make the plastic unstable if it is not removed. The materials finish polymerizing and create a finished product, melamine resin.