The Associated Press and others are reporting that milk products tainted with the toxic chemical melamine are on sale again in China.
Melamine-tainted milk products have been pulled from convenience store shelves in southern China more than a year after hundreds of thousands of children were sickened in a massive milk safety scandal, a government spokeswoman said Monday.
I originally covered this scandal in which melamine was added to dairy products to spoof higher protein levels in baby formula milk and other foods back in 2008. Several thousand babies in China became ill, having suffered acute kidney failure, with several fatalities.
Melamine is an organic compound, a base with chemical formula C3H6N6. Officially it is 1,3,5-triazine-2,4,6-triamine in the IUPAC nomenclature system (CAS #108-78-1). It is has a molecular mass of just over 126, forms a white, crystalline powder, and is only slightly soluble in water. It is used in fire retardants in polymer resins because its high nitrogen content is released as flame-stifling nitrogen gas when the compound is burned or charred.
Indeed, it is this high nitrogen level – 66% nitrogen by mass – in melamine that gives it the analytical characteristics of protein molecules. Melamine can also be described as a trimer of cyanamide, three cyanamide units joined in a ring. It is described as being harmful according to its MSDS sheet: “Harmful if swallowed, inhaled or absorbed through the skin. Chronic exposure may cause cancer or reproductive damage. Eye, skin and respiratory irritant.” Not something you would want in your infant’s milk. However, that said, the toxic dose is rather high, on a par with common table salt with an LD50 of more than 3 grams per kilogram of bodyweight.
The AP report claims that the Chinese authorities had said they would clamp down on on this toxic food fraud, but named among the culprits in the new scandals a company that was allegedly involved first time round and had been under investigation for a year.
Washington Post AP link