The exporters of medicinal plant based products may soon have to comply with a new international guideline on 'Good Agricultural and Collection Practices' if they are to find their products acceptable in the developed countries. The new guideline once accepted and incorporated under national laws, can turn mandatory for medicinal plant export clearances, it is learnt.

The guidelines for good agricultural and collection practices for herbal industry has been announced by the World Health Organisation (WHO) in response to the growing reports of adverse effects from herbal medicines and the realization of the fact that over harvesting could lead to the extinction of endangered species. Global herbal industry is estimated to be worth more than $60 billion a year.

The WHO guidelines are intended for national governments to ensure that the production of herbal medicines, which can be the natural, readily available answer to some ailments, is safe, posing no threat to either people or the environment.

"Herbal medicines are growing in popularity in wealthy countries and their use remains widespread in developing regions. But poor quality of raw plant materials and wrong identification of plant species are a major cause of adverse effects. Cultivating, collecting and classifying plants correctly are therefore of the utmost importance for the quality and safety of products," the WHO has observed.

The Guidelines on Good Agricultural and Collection Practices for Medicinal Plants also warn that the growing market and its great commercial benefit might pose a threat to biodiversity through over-harvesting of raw materials for medicines and natural health care products. If not controlled, these practices may lead to the extinction of endangered species and the destruction of natural habitats and resources.

The guidelines cover the spectrum of cultivation and collection, including site selection, climate and soil considerations and identification of seeds and plants, as well as the main post-harvest operations and legal issues such as national and regional laws on quality standards, patent status and benefits sharing.

Among the risks highlighted are inadvertent contamination by microbial or chemical agents and misidentification of plants or intentional adulteration. In this context, the report cites caarrhythmias reported in the United States in 1997 after the accidental substitution of plantain, to be used as a dietary supplement, with Digitalis lanata, generally used for heart conditions.

Among endangered medicinal plants the guidelines mentioned the reported rapid decline due to increasing demand of wild ginseng used for digestive conditions resulting from nervous disorders. Wild American ginseng, goldenseal, echinacea, black cohosh, slippery elm and kava kava top the "at-risk list" of endangered species of medicinal plants.