For years Chinese dairy producers have been making trips to the local tannery, collecting the chemical scraps left over from the leather softening process, putting it into milk, and thereby boosting the milk’s protein content as measured in tests.
But the chemicals they are adding—hydrolyzed leather proteins, sodium and potassium dichromate, the chemical hexavalent chromium (CrVI)—cause cancer.
The toxic milk has been dubbed “leather milk.” The most vulnerable victims are infants.
The issue had been reported as early as 2005, but recent reports in the Chinese media, along with high-profile denials by the Communist Party that there were any problems, brought it to light again.
Zhejiang Metropolitan Daily reported that five out of eight batches of dairy drinks from Chenyuan Dairy Co., Ltd. in Jinhua City, Zhejiang Province, contained high levels of hydrolyzed protein from leather. Additionally, six batches of products sold to Longyou, Haining, and Jiashan markets all contained hydrolyzed leather proteins.
Hong Kong’s Wenweipo reported as early as 2005 that at least 200 diary factories in Shandong Province added leather hydrolyzed protein to their products.
Xinhua reported in July 2005 that in Shanxi Province, artificial milk was made out of materials that have nothing to do with real milk, such as synthetic flavoring, protein hydrolysate, and additives. Such artificial milk was then sold under famous brand names.
In March 2009 a site inspection of Chenyuan Diary Co., Ltd. revealed three 20 kg bags of leather hydrolyzed protein, along with 1,300 boxes of tainted dairy products. Similar cases were also reported in Shandong, Shanxi, Hebei provinces.
China State Council Food Safety Administration issued a notice on Feb. 13 that since July 2010 they have uncovered 40 illegal dairy product manufacturing and sales facilities. A total of 2,131 tons of tainted milk powder were confiscated.
Wang Xiaofeng, a Beijing food inspection expert, said it is more difficult to detect leather hydrolyzed protein than melamine, because it is a type of protein itself. The inspection method devised by the Ministry of Agriculture checks if hydroxyproline, a type of hydrolyzed animal collagen, is contained in the dairy products. If so, it can be inferred that the product contains leather hydrolyzed protein.
Social System Broken
Dishonest traders often add water to milk. The milk is thereby diluted and cannot pass nutrition analysis tests because of reduced protein content. Substances are then added to ensure an acceptable protein level.
Xinmin Weekly once quoted a dairy industry insider saying that a ton of protein hydrolysate costs 1,000 yuan. The cost of producing one ton of milk powder—including fresh milk, labor, water, and electricity—is at least 20,000 yuan. However, if protein hydrolysate was added the cost can drop down to 4,000 or 5,000 yuan.
Milk is mostly consumed by children and is the only source of nutrition for infants. The devastating consequences of a previous scandal, in 2008, involving the chemical melamine, caused at least six painful deaths due to kidney stones, and left millions of young children sick, with potential future health problems.
At that time Communist Party authorities covered up the poisonings until the Olympic Games were over.
Professor Guo Yuhua from Tsinghua University Department of Sociology says it’s a problem of China’s social system, where everyone is looking out for their own interest.
Next: "A society where people are poisoning each other."