The health ministry termed the observations made in the August 27 issue of the Journal of the American Medical Association on the presence of toxic metals beyond permitted levels in Ayurvedic medicines as flawed.

Terming the report as a 'rehash' of an earlier JAMA article by the same author in 2004, the ministry said it discloses 'a strong bias against Ayurvedic medicines.'

The ministry said India does not 'officially' export herbo-metallic compounds due to heavy metal concerns. 'Only purely herbal Ayurveda, Unani and Siddha medicines are being exported from India with effect from January 1, 2006,' a ministry press release said.

The earlier JAMA report, also by Robert B Saper of Boston Medical Centre, had prompted drug regulatory agencies of the US and European countries to repeatedly warn against the use of Indian Ayurvedic products and ban some of them in 2004.

"It is an outdated study, based on 2005 data of some Ayurvedic drugs available on the Internet. The authors are consciously trying to malign the reputation of Ayurveda at a time of global recognition," Ranjit Puranik, general secretary of Ayurvedic Drug Manufacturers Association, said.

The ADMA has a cooperation agreement with the American Herbal Products Association and plans to take up the issue with its US counterparts.

The Department of Ayurveda, Yoga and Naturopathy, Unani, Siddha and Homoeopathy said that the issues raised in JAMA, howsoever flawed, will be responded to by Indian scientists on the basis of their research on Ayurveda herbal and herbo-metallic medicines through research publications in due course.

India's AYUSH industry, which consists of a dozen big players and over 2,000 small- and medium-scale units, export value-added drugs worth over Rs 500 crore (Rs 5 billion). The country's herbal industry is worth over Rs 8,000 crore (Rs 80 billion).