In ongoing coverage, the New York Times reports that officials from the Food and Drug Administration (FDA) have identified a contaminant that may be responsible for 19 recent deaths linked to the blood thinner heparin.

Baxter, the pharmaceutical company that makes heparin, recently issued large scale recalls of the product in both the United States and Germany.

Now, officials say that sophisticated testing never before used to analyze prescription drugs has identified what appears to be an unusual contaminant in the recalled batches of heparin. The substance, which was undetectable by normal means of analysis, seems to be some type of heparin mimic, and was likely the cause of the allergic-type reactions reported by patients.

Investigation has tied the contaminant to production facilities in China, a new blow for suppliers of raw ingredients from that country, who have already been hit with several recall notices due to contaminated products ranging from dog food to children's toys.

The raw ingredients for heparin come from pig intestines, and many of the initial compounds are produced in China, then shipped to the United States and Europe, where they are refined and blended to produce the actual ingredients that makers like Baxter use to produce final products.

Tests showed that up to 20% of the active ingredient in the recalled heparin had been replaced by the hard to detect mimic. FDA sources are not yet speculating on whether the contamination was accidental or the result of deliberate cost savings measures by Chinese suppliers.

What is clear is that this new information should make screening the rest of the heparin supply quick, though likely expensive. Baxter has not issued any statements about whether the new screening techology will become a standard part of the heparin production process.