SHANGHAI — Chinese regulators are widening their investigation into contaminated food amid growing signs that the toxic industrial chemical melamine has leached into the nation's animal feed supplies, posing health risks to consumers.
The announcement came after food safety tests earlier this week found that eggs produced in three different provinces in China were contaminated with melamine, which is blamed for causing kidney stones and renal failure in infants. The tests have led to recalls of eggs and consumer warnings.
The reports are another serious blow to China's agriculture industry, which is already struggling to cope with its worst food safety scandal in decades after melamine-tainted milk supplies sickened over 50,000 children, caused at least four deaths and led to global recalls of goods produced with Chinese dairy products earlier this fall.
The cases are fueling global concerns about Chinese food. In Hong Kong, food safety officials announced this week that they would begin testing a wider variety of foods for melamine, including vegetables, flour and meat products. On the mainland, Shanghai and other cities are moving aggressively to test a wide variety of food products for melamine, including fish and livestock feed, according to the state-run news media, which has in recent days carried multiple reports on melamine in animal feed.
In the United States, worried consumers frantically e-mailed one another on Thursday and Friday about the possibility of melamine-tainted Halloween treats following a spate of news reports that some candies and chocolates made in China or with ingredients sourced in China had tested positive for high levels of melamine or been destroyed in recent weeks as a cautionary measure.
A spokeswoman for the Food and Drug Administration said the agency was adjusting a nationwide sampling of products for melamine "as necessary." The FDA, along with state and local authorities, have been sampling products in Asian markets since mid-September for traces of melamine.
"Thus far, most of FDA's testing of milk and milk-derived ingredients and products from China focused on human foods, but have included animal feeds as well," said the spokeswoman, Stephanie Kwisnek. "The FDA is currently re-evaluating its overall approach to keeping these products out of the U.S. market."
Asian food safety experts warned consumers not to grow too alarmed over the finding of tainted eggs because they contained much lower concentrations of melamine than the powdered baby formula that caused such widespread problems in China.
Hong Kong food safety officials said a child would have to eat about two dozen of the eggs in a single day to become ill.
Still, if eggs, milk and animal feed supplies are tainted, there is the specter of an even wider array of foods that could come under scrutiny, everything from pork and chicken supplies to bread, biscuits, eggs, cakes, seafood and candy.
China is also one of the world's largest exporters of food and food ingredients, including meats, seafood, beverages and vitamins.
Melamine was banned as an animal feed additive in China in July 2007. And last year, United States regulators put tough restrictions on the amount of melamine allowed in food products.
But interviews on Friday, and over the past year, with several Chinese chemical dealers who sell melamine suggests that melamine scrap, the substantially cheaper waste left over after producing melamine, continued to be added to animal and fish feed.
"I heard some melamine dealers still sell to animal feed producers," said Qin Huaizhen, manager at the Gaocheng Kaishun Chemical Co. in city of Shijiazhuang, though he insisted he has never sold melamine to animal feed producers. "In Shandong province many animal feed manufacturers buy melamine scrap."
Two other melamine dealers in east and south China said that only after the recent dairy scandal did government regulators begin to closely monitor the sale of melamine to animal feed producers.
Kidney experts said that there has been very little research into how the chemical disrupts kidney function. Dr. Fredric Coe, a professor of medicine at the University of Chicago, said that melamine is likely concentrated in the kidneys into crystals that the body cannot dissolve. Those crystals clog many of the kidney's nearly one million nephrons, which are tiny filtering units, in a process very different from the usual way kidney stones are formed, Coe said. Urination slows or ceases, and patients suffer acute kidney failure.
Some food-safety experts are perplexed as to how melamine was allowed to seep into China's food supplies after melamine-tainted animal feed exports from China were blamed last year for sickening dogs and cats in the United States, touching off international trade and food safety disputes between the two countries.
"A year ago, everybody should have been in a complete panic about it, and done something then," said Marion Nestle, a professor of food studies and public health at New York University and the author of "Pet Food Politics" (University of California Press, 2008), which examines the pet food problem in detail. "Someone should have required that melamine not be in any food product."
The pet food case led to a vast recall in the United States and other parts of the world and also sparked a lengthy food safety crackdown in China, with regulators boasting that they had closed down thousands of illegal or substandard food factories and slaughterhouses.
Still, the Chinese government never made clear last year or even this year how extensively it had tested its own food and feed supply for melamine, even though melamine dealers acknowledged it was common to sell melamine scrap into the food and feed market.
In the dairy case, Chinese investigators have arrested dozens of suspects and blamed the scandal on a group of rogue milk and melamine dealers who they accuse of intentionally adding melamine, which is commonly used to produce plastic and fertilizer, to milk supplies as cheap filler in order to save money.
High-ranking government officials, including the head of the nation's quality watchdog, have been fired in the wake of the recalls and Beijing has acknowledged that "lax regulation" contributed to the scandal.
Similarly, last year, regulators in Beijing largely blamed the pet-food debacle on a pair of small exporters, who regulators said shipped feed or feed ingredients contaminated with melamine in order to save money and cheat the buyers.
Beijing also insisted its food safety problems were exaggerated, perhaps partly as a protectionist ploy to slow the boom in Chinese imports.
But several farmers and melamine scrap dealers said in interviews last year that melamine had been used for years in animal feed, particularly fish feed. Many melamine producers say they believed melamine scrap was nontoxic and would not be harmful to animals or humans.
Melamine dealers say the government crackdown on the sale to feed producers only occurred this year, after the Sanlu Group dairy company announced that its infant milk formula was tainted with melamine. That announcement, which came in September, triggered a nationwide recall and government announcements that other major dairy brands were also selling melamine-contaminated milk.
"Before the Sanlu scandal, we were not banned from selling melamine to anyone" Niu Qinglin, manager of the Hebei Jinglong Fengli Chemical Co., said in a telephone interview Friday. "I had heard melamine dealers sell melamine to animal feed companies and food companies; it was common before the Sanlu scandal."
Niu, however, said he never sold melamine or melamine scrap to food or feed producers. And he noted that regulators had moved in on the trade. "Now, the government regulates that melamine cannot be sold to any animal feed manufacturers or food processing companies," he said.
