But the company, BMK International, was acting on orders from the U.S. Food and Drug Administration, which found that the allergy-fighting compound was contaminated with a toxin shown to damage kidneys severely and possibly cause cancer. The incident was not an isolated event, say government officials, but the tip of an iceberg that could have serious health consequences for a small but rapidly growing group of consumers who are turning to Chinese herbalism to ease their pains and soothe their minds. Dozens of Chinese herbal remedies on sale in the United States, they believe, contain the toxin, aristolochic acid, which naturally occurs in many of the herbs used in these centuries-old Chinese healing compounds. The toxin has already been fingered in a mass outbreak of kidney trauma in Belgium, possibly causing cancers in more than 30 people there, and is suspected of the same in several other countries. Federal officials are unsure how widespread the contamination is.
Herbal manufacturers insist it is quite limited.
Last summer, the FDA aggressively began seizing cargo shipments from China suspected of carrying the worrisome herbs, according to federal trade documents. The agency bombarded doctors with letters urging a detailed exploration of their patients' Chinese herbal remedy use. And it warned the herbal industry to police itself, both in the United States and in China, where many of the herbs originate. Herbal companies contend that the FDA is being heavy-handed, taking dramatic actions based on minimal evidence. But the FDA and health advocates say the effort is actually evidence of the agency's impotence in controlling herbal and dietary supplements.