FDA says recalled heparin contained contaminant

— -- In a finding eerily similar to the contamination of pet food last year, the Food and Drug Administration said Wednesday that a counterfeit chemical has been detected in recalled supplies of the blood thinner heparin.

Nineteen people have died since Jan. 1, 2007, from allergic reactions that appear to be associated with contaminated heparin, says Janet Woodcock, acting director of the FDA's Center for Drug Evaluation and Research. The death toll had been four.

Last year, thousands of pets fell ill after eating food made with adulterated wheat flour from China. The flour contained two industrial chemicals, melamine and cyanuric acid, added to make it appear to be the more expensive wheat gluten.

Baxter, which supplied half of the heparin used in U.S. clinical settings, first recalled some of its heparin products on Jan. 17. The company expanded the recall on Feb. 27 to include all of its multidose, single-dose and Hep-Lock products, used to flush intravenous lines to ensure that they aren't blocked by blood clots.

Heparin is commonly used in many medical and surgical procedures. Initial analyses could find nothing wrong with the recalled product, says Woodcock.

"It reacts like heparin in some of the conventional tests used for heparin, which is why conventional acceptance tests of this ingredient might not detect this contaminant," she said.

But sophisticated tests by Baxter and the FDA, including nuclear magnetic resonance spectroscopy and capillary electrophoresis, showed slight differences. The counterfeit chemical is very like heparin in its molecular makeup and is also from an organic source, says Baxter's Peter Arduini. The raw ingredient in heparin comes from the lining of pig intestines.