The FDA recently announced that as many as 15 people might have been killed by a contaminant present in heparin, a biological product purified from pig intestines and used to prevent blood clots after a heart attack or during certain medical procedures.

The first step in the preparation of this deadly batch of heparin was completed in a plant in China that is co-owned by an American company. This raw material was in turn processed at a plant in Wisconsin.

It's not yet clear exactly where and at what stage the heparin was contaminated, but perhaps we can be forgiven if we're all a bit gun-shy these days about medical products coming out of China.

This recent scare got me thinking about the many stories we've read this past year about adulterated Chinese products. I first became aware of the problems with health products imported from China when some of their dietary supplements were found to be contaminated with dangerous heavy metals, or else spiked with prescription drugs that actually led to their beneficial effects.

During the first half of 2007, we learned that lots of other unsafe products have been manufactured in China, with many of them then being exported to the U.S.

April 2007. The U.S. Food and Drug Administration (FDA) confirmed about 15 deaths in cats and dogs from eating pet food containing wheat gluten from China. The gluten had been spiked with a cheap chemical called melamine, which is present in plastics and pesticides. Nearly 100 brands of cat and dog food made with wheat gluten were recalled in the U.S.

May–June 2007. Consumers were advised to discard all toothpastes made in China after U.S. health officials found that some contained diethylene glycol, a poison used in antifreeze. The diethylene glycol had apparently been substituted for a more expensive but safe chemical called glycerin, which is routinely added to toothpastes, foods, drugs, and other products.

Late June 2007. The FDA banned farmed seafood from China because repeated testing turned up traces of antibiotics and antifungal drugs not approved in this country for use in seafood farming.

First half of 2007. Chinese inspectors announced the closure of 180 food factories and the seizure of tons of candy, pickles, crackers, and seafood tainted with formaldehyde, illegal dyes, and industrial wax. In addition, about 420 bottles of fake albumin, the blood protein, were discovered in hospitals in one Chinese province.

Summer 2007. Federal regulators warned consumers that millions of toys imported from China, ranging from Barbie doll accessories to toy trains, were coated with paint containing lead. In June 2007, the Consumer Product Safety Commission specifically recalled 1.5 million "Thomas and Friends" wooden railway toys because of lead paint.

Concerning the latest crisis of tainted heparin, the hazard could have been due to a deliberate adulteration of the product, a chance error made during preparation, or the result of trying to cut corners during the manufacturing process in order to save money.

Investigators from the FDA have indeed found manufacturing problems in the Chinese heparin plant, and Baxter International, a pharmaceutical company that sells and distributes heparin, has withdrawn virtually all of its heparin products from the market. Fortunately, another producer of heparin has stepped up its production to meet the needs.

Recently, German drug regulators have recalled heparin supplies there as well, following reports of about 100 adverse events in that country associated with injections of the drug. It's not clear yet whether the initial steps in the preparation of the tainted German supplies took place in China.

In any case, we clearly need either to stop fueling the Chinese economy by importing their flawed products or to substantially increase our funding for the agencies charged with inspecting products imported from China and other countries.