Researchers have warned that traditional Ayurvedic medicines and herbal supplements manufactured in United States and India may contain unacceptably high levels of lead, and other toxins. The study in the Journal of the American Medical Association has reported that nearly 21 % of Ayurvedic medicines actually contain lead, mercury or arsenic especially products that are sold via the Internet.

Ayurvedic medicines are largely plant based and have been used by Indians as well as worldwide by people from South Asia and other regions for many years. Dr. Robert B. Saper, from Boston University School of Medicine, and colleagues said, "However, since 1978 more than 80 cases of lead poisoning associated with Ayurvedic medicine use have been reported worldwide."

Arsenic can cause cancer, lead and mercury lead to damage in the kidneys and brain especially in the case of children. More than 80 people worldwide have developed lead poisoning, reports the study with symptoms that include fatigue, anemia and abdominal pain.

Ayurvedic medicines are largely manufactured for use in adults to treat problems such as indigestion to infertility though the researchers found that 4 % of the medicines they examined were labeled for use in children. These traditional medicines come in two types- herbal and rasa shastra. In the ancient practice of rasa shastra herbs are deliberately combined either with certain metals such as mercury, lead, iron and zinc, minerals like mica etc or gems like pearl etc. The claim is that when these are carefully prepared and properly administered they are safe and beneficial.

Michael McGuffin of the American Herbal Products Association, whose members include the makers of traditional herbal products says about 750,000 Americans have used Ayurvedic medicines.

Saper and his colleagues bought all the medications on the Internet and out of the 193 they examined 20.7 % of the products showed a presence of metals. The American made Ayurvedic medicines had a higher rate at 21.7 % compared to Indian manufactured products which were at 19.5 %. The researchers also found that the rasa shastra medicines were more than twice as likely to contain detectable metals when compared to herbal ones with a tally of 40.5 % compared to 17.1 % and a higher concentration of lead and mercury as well.

"Several Indian-manufactured rasa shastra medicines could result in lead and/or mercury ingestions 100 to 10,000 times greater than acceptable limits. Among the metal-containing products, 95 percent were sold by U.S. Web sites and 75 percent claimed Good Manufacturing Practices," the researchers noted.

The manufactures of the websites mentioned have said that they test their products for safety, but McGuffin feels it would be impossible to ensure products being 100 % lead free as lead can be found in both soil and water and could easily contaminate fruits, vegetables and even dairy products.  Peter Bowes, owner of Seattle-based Tattva's Herbs, says his company's own tests found much lower lead levels than those listed in the study.

Saper told Reuters Health, "Current regulations governing the quality of herbal supplements made and sold in the US and India are inadequate. We recommend strictly enforced government-mandated daily dose limits for toxic metals in all dietary supplements. Manufacturers should have to demonstrate compliance with these standards through independent third-party laboratory testing."

McGuffin says that as government and professional agencies set widely different safety standards for lead, mercury and arsenic it would be difficult to set a level. Though most of the products checked in the study have lead levels that exceed California's standard, only two violate the World Health Organization's standard.

The Food and Drug Administration should set maximum daily dose limits for toxic metals in dietary supplements, feels Saper. The FDA currently doesn't specify how much lead is permitted in these products, but it can pull products off the market if they're found to be unsafe. "If we know what the target is, it makes it easier to hit the target," said McGuffin adding that the government and industry should seriously consider such limits.

Saper and his colleagues recommended that the herbal Ayurvedic medicines should be used rather than the rasa shastra medicines. "Although the current study focused on Ayurvedic medicines, reports of similar problems with toxic metals in other traditional medicines (e.g. Chinese, Mexican, Middle Eastern) and Western herbal supplements have been reported, Saper said.

"Products made by members of the American Herbal Product Assn; capsules/liquids/pastes; are less likely to contain toxic metals," Saper said. "Products that have obtained seals of quality approval from Consumer Lab.com and the United States Pharmacopeia (USP) can be assumed to be free of significant levels of toxic metals," he concluded.