(Thanks to Peggy who posted the link at petconnection!)
From the Pittsburgh Tribune-Review.
By Karen Roebuck
Wednesday, May 2, 2007
As more contaminated human and pet food products are found daily, the biggest unknown remains the long-term health effects from eating food laced with industrial chemicals, doctors and researchers said Tuesday.
"That is one thing people are still concerned about -- long-term effects -- and we still don't know the answer to that," said Dr. Wilson Rumbeiha, a pathologist with Michigan State University's Center for Population and Animal Health. Rumbeiha is working with the U.S. Food and Drug Administration on the pet food contamination.
Between 2.5 million and 3 million Indiana-raised chickens that ate contaminated feed were slaughtered in March and are in the human food supply, U.S. Department of Agriculture and FDA officials announced yesterday. The processed meat will not be recalled, but 100,000 other birds that ate contaminated feed will not get into the food chain, they said.
About 6,000 pigs in six states ate contaminated feed, but only several hundred are believed to have been sold to consumers. The surviving pigs will be put down, but the sold pork will not be recalled, federal officials said.
The FDA is refusing to accept shipments of 11 vegetable protein ingredients from China used in many human and pet foods, from energy bars to baby formulas to gravy. The FDA is testing samples of those ingredients and human foods at hundreds of manufacturing and processing facilities nationwide.
Four chemicals -- melamine, a chemical used in plastics; cyanuric acid, a chemical commonly used in pool chlorination; and their by-products, ammelide and ammeline -- have been found in wheat gluten, rice protein concentrate and in the urine, kidneys and tissues of infected cats and dogs, Rumbeiha said.
Since March 16, 153 brands of cat and dog food have been recalled.
Few health studies have been gauging the effects of ingesting the four contaminants, and no studies have looked at the impact of consuming them in combination, he said.
"We all believe that individually these compounds that are named alone are not that dangerous, but together they are more toxic," Rumbeiha said.
Still, USDA and FDA officials are quick to say that they believe the health risk to humans is minimal, and less than to pets, because of the "dilution effect." Animals tend to consume one type of food all the time, while humans eat a variety, they said.
Rumbeiha, Dr. Bruce Dixon, director of the Allegheny County Health Department, and other doctors and veterinarians said that while people and many pets are unlikely to become seriously ill immediately after consuming tainted foods, they may be suffering kidney damage that won't be evident for years.
Humans can function normally until nearly 90 percent of their kidneys shut down, and sometimes do not realize they have a problem until they need dialysis, said Dr. Stephen Sandroni, director of the division of nephrology and hypertension at Allegheny General Hospital on the North Side.
"It's not unlike secondhand smoke; it's not unlike asbestos; it's not like aspirin and phenacetin, which affected kidneys. It's a slowly damaging process," Dixon said. "I don't think anybody has the data yet to suggest it's not a significant risk. I think it is."