Tainted animal feed: a brief overview
More than a month after the first chemically tainted pet food was recalled, melamine continues to be found in animal feed -- including meal for livestock and fish destined for human consumption.
The U.S. Food and Drug Administration has said that people are not at risk because the tainted ingredients were diluted before being fed to the livestock and fish, but many questions persist.
How did the problem come to light?
Menu Foods Income Fund, a Canadian-owned pet food manufacturer that supplies foods for dozens of private-label and popular pet food brands, announced a recall of 60 million containers of moist dog and cat food in March.
At the time, the company said 10 animals had died of kidney failure after eating the food.
What caused the pet illnesses and why would the chemicals be added to pet food?
The FDA said the food contained ingredients tainted with melamine (used in making plastic) and cyanuric acid (used to sanitize pool water), and that the interaction between the chemicals probably caused renal failure in the animals.
Those chemicals, which are high in nitrogen, might have been added to make the food ingredients appear protein-rich, since a common protein test evaluates nitrogen content.
Where did the tainted ingredients originate?
The FDA says the contaminated ingredients came from China.
How many pets have died?
The FDA so far has confirmed 16 deaths related to the pet food contamination, although officials have said they expect that number to rise. An FDA hotline has received 17,000 complaints from the public. Of the 8,000 calls the agency has logged so far, about 4,000 have reported that a cat or dog died after eating the contaminated food.
What animals in the human food chain have been affected, and what has happened to them?
The Department of Agriculture, which regulates meat and poultry, has said that several livestock farms bought salvaged pet food before the melamine contamination was discovered. The tainted products were then mixed with other foodstuffs to create feed for more than 23 million chickens and 56,000 hogs.
As many as 3.1 million chickens at 38 farms in Indiana may have received contaminated feed in early February and were slaughtered for human food a few weeks later. About 6,000 hogs in California, Kansas, New York, North Carolina, South Carolina and Utah also could have eaten tainted food; about 5,600 of them are still on farms. On Tuesday, food safety officials said an additional 50,000 swine in Illinois also might have been fed contaminated feed.
Agriculture officials lifted the quarantine on 20 million chickens after tests of their feed failed to find melamine and related compounds. Animals on farms where feed tested positive for the chemicals are being held until the USDA determines whether the animals are safe for use as food, the agency said.
The agency has declined to name the farms or the brands under which the animals are sold.
Why do officials say humans aren’t at risk, if pets died?
People are at “very low” risk, food safety officials have said, because of the “dilution effect” -- the tainted products were mixed with other food and the animals make up only a part of the human diet. In general, pet diets are limited to one or two items, and the sickened pets were fed a much higher concentration of the chemicals.
Is there a risk from eating fish?
Food safety officials again point to the “dilution effect” and say that there is no evidence of harm to people. But they cannot yet say how many commercially raised fish or fish farms might be affected by the tainted meal and are unable to identify the types of fish involved.
