THURSDAY, May 10 (HealthDay News) -- A Canadian distributor of melamine-tainted fish food has recalled the feed from 198 U.S. fish farms and hatcheries and 57 Canadian fish farms and hatcheries, U.S. health officials reported Thursday.

Experts at the U.S. Food and Drug Administration said they still do not know if any fish fed the tainted meal have made it to the U.S. market.

"The FDA is working to determine the extent of the fish feed distribution and whether any of the fish that were fed the melamine-containing product have been released into the environment or eaten by humans," Dr. David Acheson, the assistant commissioner for food protection in the FDA's Office of the Commissioner, said during the teleconference.

In the meantime, U.S. officials have placed a ban on certain grain products from China, the suspected source of the melamine-contaminated wheat flour, gluten and rice protein that sparked the recent recall of more than 100 brands of pet food nationwide.

Melamine-tainted pet food also made its way to chicken and hog feed; it surfaced this week in fish meal.

Acheson told reporters that, "Skreeting, a company based in Vancouver, Canada, is recalling fish feed due to contamination with melamine." He added that, "To date, FDA analysis has shown one positive sample of contaminated fish feed from Marion Forks Hatchery in Oregon."

The fish feed was used as a starter diet for salmon and trout, according to the Oregon Department of Fish and Wildlife. The contaminated feed was also sent to several hatcheries in the state.

According to Acheson, a risk assessment by federal health officials found that the health risk from eating fish that ate contaminated feed is "very low."

He also elaborated on the new measures in place to check imported Chinese grains.

"All vegetable protein products imported or shipped from China cannot come into the United States unless they have been tested for melamine and other melamine-derived compounds," Acheson said.

In addition, the FDA is sampling pet food imported from China and will begin testing animal feed, including fish feed.

The FDA is also visiting U.S. manufacturers that use imported protein concentrates. The FDA will be collecting samples of both raw ingredients and finished product, and testing them for melamine, Acheson said. "This domestic assignment is targeted at pet food animal food, as well as human food," he noted.

In China, FDA representatives have visited the plants of the two manufacturers of the contaminated wheat flour. Both plants were closed, and the equipment dismantled. The FDA has confirmed that executives from both companies have been detained by Chinese authorities.

More information

For more information on the pet food recall, visit the U.S. Food and Drug Administration.

SOURCES: May 10, 2007, teleconference with David Acheson, M.D., assistant commissioner for food protection, Office of the Commissioner, U.S. Food and Drug Administration

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