There is building evidence that the pets who died from pet food products were a result of melamine scrap–an extracted from coal (yes, the black stuff)–added to pet food & livestock feed by China. Of course the manufacturers there say it's harmless and adding it is a widespread practice.
The most infuriating aspect of this is that melamine is used solely to deceive tests into registering higher protein levels because of melamine's nitrogen content. Buyers in Asia and the U.S. purchase animal feed with this "fake protein" of no nutritional value as the NY Times notes. And why did they start adding melamine scrap? It is cheaper than real protein (Come on, it's scrap!) and they can't get away as easily with adding urea (yes, the stuff in urine) in fooling the tests. Talk about cheap cons.
The Times made note of other China scandals:
China’s food safety scandals have involved everything from fake baby milk formulas and soy sauce made from human hair to instances where cuttlefish were soaked in calligraphy ink to improve their color and eels were fed contraceptive pills to make them grow long and slim...all for consumption by their citizens and those who buy China's exports.