The Agriculture Department in the United States (USDA) has given approval for 20 million chickens to be sold which may have been given feed contaminated with the chemical melamine.
The USDA says it is not necessary to quarantine livestock on farms where melamine or related compounds could not be detected in animal feed, as it makes up only a small share of the feed; the 20 million chickens come into that category.
However on farms where feed tests have found melamine, or where feed samples have not been submitted or been available for tests, animals will be held under quarantine until risk assessments are completed which will determine whether they will be culled or used for food.
Scientists from five federal agencies, including the Centers for Disease Control and Prevention, have all stated that there is very little risk to people who eat the meat from livestock that ate the contaminated feed.
The scientists say even if a person ate only foods for one day contaminated with melamine at the levels in the adulterated animal feed, the potential exposure would be about 2,500 times lower than the dose considered potentially harmful.
It is suspected that the feed was supplemented with pet food scraps that contained melamine; the contaminated pet food has been responsible for the deaths of a number of cats and dogs.
The scientists now need to assess the health risk to livestock; however, they say the risk to animals that ate the tainted food is minimal because melamine, a chemical used to make plastic, does not accumulate in these animals’ bodies but is excreted in their urine.
Many poultry and hog feed suppliers from a number of states bought salvaged pet food for use in feed rations for their animals and some of the pet food contained melamine in the wheat gluten and rice protein concentrate used in making the pet food.
The government is now apparently monitoring imports of corn gluten, wheat gluten and rice protein concentrate that are destined for animal or human consumption.
The melamine was found in wheat gluten and rice protein imported from China and triggered one of the largest pet food recalls in U.S. history, a recall of more than 100 brands of pet food.
According to the USDA as many as 3.1 million chickens at 38 farms in Indiana may have been given contaminated feed in early February and many were slaughtered for human food just a few weeks later.
Also 6,000 hogs in six states, California, Kansas, New York, North Carolina, South Carolina and Utah, may also have eaten the tainted feed.
Scientists with the Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC) of the Department of Health and Human Services (HHS), the Environmental Protection Agency (EPA), U.S. Customs and Border Protection (CBP) of the Department of Homeland Security (DHS), and the Food Safety and Inspection Service (FSIS) of the U.S. Department of Agriculture (USDA) conducted the study.