A group of doctors and scientists are warning against the use of alternative Indian remedies, after finding eight patients had been poisoned with lead after using them.
"We wish to alert the medical community to a substantial threat to wellbeing posed by a particular form of herbal remedy, namely Ayurvedic
medicine," they write in the latest New Zealand Medical Journal, published yesterday.
Ayurvedic medicine is a traditional form of healing originating in India.
Citing an American study, the medical journal case report says 20 per cent of Ayurvedic preparations bought in Boston contained substantial amounts of heavy metals.
The eight Auckland and Waikato patients suffered a range of symptoms, commonly including abdominal pain, after taking Ayurvedic powders or tablets, which in one case were a treatment for male infertility.
One of the tablets had 10mg of lead and the recommended dose on the bottle was four a day.
Under the levels set by United Nations food and health organisations, a 70kg adult would exceed the tolerable weekly intake by a factor of four by taking a single tablet containing 8mg of lead.
Treatment of the New Zealand patients included chelation therapy and blood transfusions.
The researchers say the public is widely exposed to the Ayurvedic contention that, when taken correctly, "bhasmas" - carefully extracted ashes - containing lead or mercury are therapeutically beneficial.
"This belief is irreconcilable with Western toxicology. From the view of Western science, even minuscule quantities of lead have potential for harm, including irreversible brain damage, and are of absolutely no therapeutic benefit."
The researchers say the eight cases - identified from 1999 to 2005 hospital, laboratory and Auckland public health records plus one Waikato case - are the tip of a widespread problem.
Also in the journal is a Waikato Hospital study showing that a third of people attending the emergency department had used complementary or alternative medicines.
