Clinical Briefs

With Comments from Russell H. Greenfield, MD

Ayurvedic Products and Heavy Metals

Source: Saper RB, et al. Heavy metal content of ayurvedic herbal medicine products. JAMA 2004;292:2868-2873.

Goal: To determine the prevalence of heavy metals in Ayurvedic herbal remedies made in South Asia and sold in Boston-area stores.

Design: Systematic search strategy.

Setting: All stores selling Ayurvedic herbal medicine products from South Asia within a 20-mile radius of Boston City Hall.

Methods: All stores selling Ayurvedic remedies within the defined limits were identified by searching on-line Yellow Pages, an on-line directory of Indian grocery stores, a South Asia community business directory, and newspapers. Each store was visited and one package of all unique Ayurvedic botanical products offered for oral use was purchased (n = 70). Using X-ray fluorescence spectroscopy, concentrations of lead, mercury, and arsenic were determined for each product by the New England Regional Environmental Protection Agency (EPA). Using the manufacturers’ dosage recommendations, estimated daily metal intake was compared with EPA safety standards. The authors returned to the stores at a later date and attempted to re-purchase each remedy initially found to contain heavy metals, as well as a randomly generated list of 14 products found to contain no heavy metals on initial testing.

Results: Heavy metals were found in 20% (14/70) of the Ayurvedic herbal medicine products (lead n = 13; mercury n = 6; and/or arsenic n = 6). All 10 re-purchased products had heavy metal concentrations similar to that found in original samples. If ingested as directed, each product would have caused heavy metal intakes above the EPA regulatory standards. Of the 14 products selected for re-purchase that initially tested negative for heavy metals, none contained heavy metals in re-testing.

Conclusion: Users of Ayurvedic herbal medicine products from South Asia may be at risk for heavy metal toxicity.

Study strengths: Assessment of reproducibility; well-defined limits; generalizability (choosing only those products manufactured in South Asia).

Study weaknesses: Inability to identify chemical forms of the metals (which could impact degree of toxicity and bioavailability, most notably with mercury); lack of documentation of manufacturers’ recommended duration of use of remedy.

Of note: Since 1978, at least 55 cases of heavy metal toxicity associated with Ayurvedic medicinal herbs have been published; the 70 products were manufactured by 26 Indian and one Pakistani company; seven of the 70 Ayurvedic remedies purchased specifically recommended use for children (six of which contained lead, three contained mercury, and three contained arsenic); Ayurvedic theory ascribes important therapeutic value to metals like mercury and lead, which are believed to be detoxified through heating and cooling, and the addition of specific herbs.

We knew that: It is estimated that 80% of India’s population (1 billion people) uses Ayurvedic remedies; in one study of 22 herbal Ayurvedic products purchased in India, 64% contained lead and mercury, and 41% contained arsenic; lead toxicity from Ayurvedic herbal medicines has been tied to developmental delay, congenital paralysis and sensorineuronal deafness, fatal infant encephalopathy, and status epilepticus; concerns over heavy metal contamination also have been raised for traditional medicines from China, Malaysia, Mexico, and Africa; it is been estimated that 750,000 people in the United States have consulted with an Ayurvedic practitioner.

Clinical import: This well-done study raises significant concerns about the safety of Ayurvedic herbal remedies and reminds us that while issues exist with the standardization and regulation of Western medicinal herbs, the problems are compounded when considering botanicals manufactured outside the country. If Ayurvedic herbs are to be used, those manufactured in the United States should be recommended. Until safeguards are firmly established and in place, practitioners must include use of Ayurvedic herbal remedies produced in South Asia in the differential diagnosis of otherwise unexplained heavy metal toxicity.

What to do with this article: Keep a hard copy in your files and make copies for your peers.

Dr. Greenfield, Medical Director, Carolinas Integrative Health Carolinas HealthCare System Charlotte, NC, Clinical Assistant Professor, School of Medicine, University of North Carolina, Chapel Hill, NC, is Executive Editor of Alternative Medicine Alert.