COLUMBIA - Federal regulators say a pet food company improperly tested or did not test corn shipments for the deadly fungus that has been blamed for the death or illness of about 100 dogs who ate the tainted food.
According to a report to be released this week by the U.S. Food and Drug Administration, Diamond Pet Foods allowed tainted corn into its Gaston plant and did not properly test for the poison aflatoxin.
The federal agency began an investigation into the Lexington County plant after the company recalled about 1 million pounds of dried dog food Dec. 20, said Phil Campbell, the Atlanta-based FDA official in charge of the investigation.
The FDA report represents the agency's findings but does not penalize the company, The State newspaper reported Monday.
A spokesman for the FDA did not immediately return a phone call by The Associated Press on Monday seeking comment.
"Diamond Pet Foods has cooperated fully with the FDA during its investigation," company spokeswoman Carol Anderson told the newspaper Friday.
She said the company has improved its testing of incoming corn and has begun checking its final product before shipping.
"This additional step will provide an extra layer of protection," she said.
The tainted corn was from South Carolina. Southeastern states tend to have a higher occurrence of aflatoxin because of their hot, humid summers, experts say.
At more than 20 parts per billion, aflatoxin becomes too great to be used in human and pet foods, according to FDA standards.
Out of more than 1,400 tests performed by the state Agriculture Department in the past two years, a quarter found levels of aflatoxin higher than allowed by the FDA, according to records obtained by The State under South Carolina's Freedom of Information Act.
Those tests were not required by law but are provided by the state agency at no charge.
Diamond Pet Foods collected a sample from each incoming truck or rail car and used a "cup test" to determine whether aflatoxin was present at levels above 20 parts per billion.
Typically the company would get one or two tainted loads of corn each year. But beginning in September, the tests began showing one or two tainted loads a week, Chief Operating Officer Mark Brinkmann has said.
Because of the increased frequency, the company changed its testing method to better measure the toxin's concentration. That new test went into effect Nov. 30.
On Dec. 20, Diamond recalled dried pet food produced at its Gaston plant from Sept. 1 through Dec. 6, saying batches had been found with high levels of aflatoxin. By late December, the company determined the poisonous batches were produced Oct. 1-15.
The State reported Monday that based on published reports and information from state officials, about 100 dogs have died or become sick from aflatoxin poisoning in South Carolina, North Carolina, Georgia, New York, Massachusetts, Ohio and Pennsylvania.
In South Carolina, 52 dogs were poisoned by eating Diamond Pet Foods and 35 of those died, said Pamela Parnell, a pathologist who has studied the cases at Clemson University's animal research laboratory in Richland County.
At least two dogs deaths in Aiken County were linked to the tainted food.
At one household in Cherokee County, 13 dogs were poisoned, and seven died, Ms. Parnell said.
"I keep hoping people stop feeding this, and we stop seeing them," she said. "It's a slow-acting poison. It can still cause severe damage a couple weeks after you stop feeding it."