from New Scientist, 10 January 2004
THE multimillion-pound boom in herbal medicine is threatening to wipe out up to a fifth of the plant species on which it depends, wrecking their natural habitats and jeopardising the health of millions of people in developing countries. And yet the herbal medicines industry has been accused of doing nothing about it.
Most people around the globe use herbal medicine for everyday healthcare, with as many as 80 per cent relying on it in some countries. But two-thirds of the 50,000 medicinal plants in use are still harvested from the wild, and research to be published later this year suggests that between 4000 and 10,000 of them may now be endangered.
A study by Alan Hamilton, a plant specialist from the global environment network WWF, will point out that the market for herbal remedies in North America and Europe has been expanding by about 10 per cent a year for the last decade and the world market is now thought to be worth at least £11 billion. Many of the plants are harvested by poor communities in India and China whose livelihoods will suffer if the plants die out.
"It's an extremely serious problem," Hamilton told New Scientist. He is a member of the World Conservation Union's Medicinal Plants Specialist Group, and has drawn his estimates of the number of species at risk from expert analyses of the IUCN's Red List of threatened plants. His study is due to be published in Biodiversity and Conservation.
Anti-cancer drugs
Hamilton has also helped compile a report, Herbal Harvests with a Future, which is due to be unveiled next week by the conservation group Plantlife International. "With demand and commercialisation growing fast, the future of the wild plants which have helped most of humanity for centuries is now more uncertain than it has ever been," says the group's Martin Harper.
One species highlighted by Plantlife as being under threat is tetu lakha (Nothatodytes foetida), a small tree found in rainforests in south India and Sri Lanka and used for anti-cancer drugs in Europe. Others include a saw-wort known as costus or kusta (Saussurea lappa) from India whose root is used for chronic skin disorders, and the tendrilled fritillary (Fritillaria cirrhosa) from Sichuan, China, used to treat respiratory infections.
Although the crisis has been looming for years, Plantlife accuses the herbal medicine industry of failing to ensure the sustainability of its supplies. It has established that 11 of 16 herbal companies in the UK, for instance, harvest all the plants they sell from the wild, and the remaining five grow only a small proportion.
A leading UK natural skin care company, The Body Shop International, accepts that it doesn't grow its own medicinal plants, but insists that it is environmentally aware. "The protection of flora and fauna is an integral part of The Body Shop approach to products. We do not source materials derived from endangered and threatened species," says a company spokeswoman in London.
Health fads
But Plantlife says awareness of the environmental problems among companies in general is limited and sometimes vague. "Given the scale of the threat, this is alarming," Harper warns. "It is time for the industry to join forces with environmental organisations to ensure that herbal harvests have a sustainable future."
Another leading international expert on medicinal plants, Gerard Bodeker from Green College, Oxford, thinks that the assessments of the crisis by Hamilton and Plantlife are conservative. Most of the processes involved in supplying the growing market for herbal remedies are "the result of unsustainable and often destructive practices driven by poverty", he says.
The industry is characterised by changing health fads which keep favouring different plants, so there is little incentive to sustainably produce particular species, he argues. "They are eating their own nest. They are not replacing what they take."
The market for African cherry (Prunus africana), the bark of which is popular in Europe as a treatment for prostate enlargement, has collapsed because too many trees have been destroyed. In the past the trees, which grow in Africa's mountain regions, survived because traditionally less than half of their bark was harvested.
But according to a recent study by Kristine Stewart, from consultants Keith and Schnars in Florida, growing commercial pressures have led to whole forests being stripped or felled. Exports of dried bark halved between 1997 and 2000 and the main exporter, Plantecam, had to close its extraction factory in Cameroon (Journal of Ethnopharmacology, vol 89, p 3).
Lack of education
In its report, Plantlife urges the industry to invest in cultivation. It also proposes the introduction of a kite mark to identify products that have been sustainably harvested. "There is a complete lack of awareness and lack of education amongst consumers," Bodeker says. Although those that use herbal medicines might be expected to be more environmentally aware than most, that doesn't seem to be the case. "They don't make the links," he adds.
The UK's largest association of herbal practitioners, the National Institute of Medical Herbalists, is very concerned. "We all need to work together to address this issue and to put pressure on suppliers," the institute's Trudy Norris says.
