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Last stand: bog bean, Menyonthes trifoliato, is disappearing in places through medicinal use

Herbal Cures Endanger Rare Species New Scientist 15 Feb 97

A SOARING trade in herbal teas and medicines is threatening some plants with extinction, according to a new study. Eighteen species are in urgent need of protection, it says, while world sales of herbal potions are increasing by more than 10 per cent a year, with Britain probably the fastest growing market. The findings, from the consulting firm McAlpine, Thorpe and Worrier, which advises several British importers, are supported by botanists. "It's a new area of research, but of great concern," says Fiona Dennis, who is producing a separate study on the subject for the World Wide Fund for Nature. The report's main author, Govinda Worrier, says that the endangered medicinal plants with the largest international markets are Chinese ginseng, 8000 tonnes of which are traded every year, and Ginkgo biloba or the maidenhair tree, a fashionable remedy for heart ailments and dementia that is found in North America, China and Indonesia. Some 2000 tonnes of G. biloba are sold every year, a third of it in Germany, and this trade is growing by 25 per cent a year. Other leading products include Harpogophylum procumbens and Menyanthes trifoliata, both of which fight rheumatism. Jim Duke, a former botanist for the US government who advised the McAlpine study, says that American demand has endangered several South Asian medicinal plants, including the Indian yew, Taxus vallichiana. "The Indian yew has just been ripped off the hillsides of northern India and Nepal," says Duke. Its bark is sold to the US as a recognised treatment for ovarian and other cancers. Duke claims that the efficacy of some potions is a myth, and that "science could elp protect several species simply by exposing them". For instance, the herb goldenseal (Hydrastis canadensis) has become endangered in the US "partly because people buy it in the mistaken belief that it masks the presence of hard drugs such as cocaine in urine analysis". The plant is also used by athletes, apparently effectively, to conceal steroids in their urine. Christine Leon of the Royal Botanic Gardens, Kew, who is investigating the safety of Chinese medicines for Guy's Hospital in London, says that once a plant becomes rare, suppliers of such medicines often use substitutes in their products, some of which are unsafe. Leon cites Aquilaria malaccensis, which is taken as a tonic for stomach upsets and also used as incense. She says it is being overexploited "with the result that a lot of poor and adulterated product is reaching the UK now". Kew is seeking money to establish an "authentication centre" for traditional Chinese herbal medicines. Dennis points out that trade in herbal medicines is not always bad for the environment. "Many plants have been sustainably harvested for a long time," she says. One example is witch hazel, made from the bark and leaves of the American shrub Hamamelis virginiana. Worrier wants the large trading companies to form a conservation organisation that would employ scientists to identify threatened species and encourage cultivation to relieve wild stocks. Cultivation is most developed in Germany, the world's largest market for herbal products with a trade worth more than FI-4 billion a year. However, Duke warns that consumers sometimes prefer wild versions. Wild ginseng, for example, produces a wiry root.

Fred Pearce

Chinese medicine and Conservation of Rare Species New Scientist Jan 3 98

FOLLOWING the second Opium War, which ended in 1860, Britain and other colonial powers demanded that China legalise the opium trade. The Chinese refused. In retaliation British troops ransacked the Summer Palace in Beijing. Some of China's greatest artistic treasures were destroyed. Echoes of this historic clash reverberate in contemporary confrontations between conservationists and the people who trade, prescribe and use traditional Chinese medicine (TCM). Many of the latter regard foreign demands for regulation of TCM to protect endangered species as a form of cultural imperialism. "I agree that all herbalists have duties to protect the endangered animals," says one Hong Kong TCM trader. "However, we are equally obliged to use these anfidotes to cure the patents. In my opinion, human lives are much more important than those of the animals." Faced with such views, conservafionists feel discouraged. Meanwhile, a treasure trove of natural heritage is under threat. Last year, China was among 136 nafions to sign a formal resolufion recognising that the uncontrolled use of wild species in traditional medicine threatens their survival and the continuation of these medical practices. The resolution, drawn up by the UN Convention on International Trade in Endangered Species (CITES), aims to initiate new partnerships in conservation. It sees education as crucial to prevent the overexploitation of medicinal species. At the same time, it acknowledges the importance of traditional medicine. Finding a sustainable way to practise TCM is crucial because it is by far the biggest of the many systems of traditional medicine that use animals and plants, and it exploits a huge range of natural ingredients. At least a quarter of the world's population, including ethnic Chinese on all continents, Koreans and Japanese, use medical practices based on TCM. Trade in Chinese medicines was worth around $2 billion to China in 1994, and is growing rapidly. About 85 per cent of these medicines are derived from plants, with 13 per cent coming from animals, and 2 per cent based on minerals. Up to 12 of these ingredients are mixed to give an individually tailored prescription. TCM sees the body as a microcosm of the natural world. Illness results when there is an imbalance, and equilibrium is restored through medication, rest and exercise. It is one of a handful of alternatives to Westem medicine that are endorsed by the WHO. Western notions of TCM are confused. It is commonly stigmatised as mere superstition yet it provides the basis for some successful Western medicines. Artemisin, for example, extracted from daisies and used by TCM practitioners for 1500 years, is now a very promising anti malarial drug in the West. Ephedrine, pre scribed for the treatment of asthma, comes from a plant that has been used in Chi nese medicine for millennia. One TCM cure for eczema proved so successful in recent trials at London's Great Ormond Street Hospital that a pharmaceuticals company has patented its own version. A key ingredient is root from the slow growing tree peony, which could rapidly become overexploited in the wild. While Westem medicine quietly assimilates traditional Chinese cures, TCM is also evolving. China has an official policy of running two healthcare systems in parallel. A doctor might use a CT scan to check for blood clots in a stroke patient, and then prescribe traditional medicines to disperse them. Although the philosophy of TCM remains traditional, treatments ani changing in response to new diseases and approaches, often at the expense of wildlife. The earliest known pharmacopoeia, dating from the first century BC, lists 365 different plants, animals and minerals. The number is now 11 559. Add to this an exploding demand for TCM, in part due to increased prosperity in Southeast Asia, and the effects on wildlife can be devastating. Field surveys assessing conservation risks posed by TCM deal almost exclusively with the few medicinal mammals. The results are disheartening. Continued demand for tiger bones makes overexploitation a greater threat than habitat loss. Similarly, medicinal use of rhinoceros cn hom has accounted for much of the animal's decline in numbers. Between 1970 and 1993, 95 per cent of the world's population of black rhinoceros disappeared, and Javan and Sumatran rhinos hover on the brink of extinction. Demand for bear bile still threatens Asian bears, even though there are now regulations on intemational trade in all species. Little or nothing is known about the biology, trade or conservation status of thousands of other nomnammahan medicinal species. And the speed at which Chinese medicine is growing means that some species newly recruited to the pharmacopoeia could become threatened even before outsiders, and some practitioners, reahse they are being used. For example, sea moths-small marine fishes that like seahorses, are used to treat many conditions from respiratory problems and impotence to general malaise-have been a recognised TCM medicine for less than 30 years. Now they are actively traded by China, Hong Kong, Indonesia, the Philippines and Vietnam. How this might affect the species' survival remains uncertain because so little is known about their ecology. Medical practitioners often do not need ecologists to tell them that trade in a species is taking its toll on wild populations. They know, for example, that trade in seahorses boomed in the n-dd-1980s, following China's economic restructuring. Traders in China estimate that sales are still increasing by between 8 and 10 per cent a year, with a global total of at least 20 milhon dried seahorses traded in 1994. Southeast Asia's seahorse populations have slumped by up to 70 per cent in the past decade. Greater demand and dwindling supplies are forcing TCM merchants to seek stock from as far afield as Ecuador and Mozambique. And this is not an isolated example-trade networks throughout Southeast Asia supply China's demand for turtles and tortoises.

Conflicting interests

As demand increases and supplies decrease, prices rise. So do conservation concerns. Rare or depleted species with inflated price tags are especially at risk because their value makes it worthwhile for suppliers to collect even the very last animal or plant from the wild. This ah-eady seems likely with the Chinese threestriped box turtle, according to a recent report from TRAFFIC, the trade-monitoring programme of the World Wide Fund for Nature, and the World Conservation Union. Highly coveted species often become important sources of income: seahorses now support thousands of subsistence fishers in Asia, many of whom could not otherwise make a living. The growing use of prepackaged patent medicines has made matters worse. Consumers increasingly rely on proprietary products.

Farming alone can never resolve conservation concerns, as consumers often prefer wild ingredients, believing them to be more potenty medicines because they are easier to use cn than traditional, individually tailored prescriptions of raw materials. This places more pressure on targ et species. Seahorses, for example, once had to be of a certain size and quality before they were accepted by practitioners and consumers. But declining availability of the preferred Z large, pale and smooth seahorses has been offset by the shift towards prepackaged medicines, which make it possible for TCM merchants to sell previously unused juvenile, spiny and dark-coloured animals. Today almost a third of the seahorses sold in China are prepackaged. Most countries where TCM is practised are well aware of conservation issues and have legislation to control exploitation of threatened species. Enforcing these laws is difficult, however. The vast majority of medicinal animals and plants are collected from the wild, making regulation of suppliers an unwieldy task. All seahorses are caught at sea by hand or in nets. And about 80 per cent of the 1000 plant species most commonly used in TCM come from wild populations. The China Plant Red Data Book lists 388 endangered species, of which 22 are still harvested from the wild virtually unchecked.

Slow to grow

One solution is to farm medicinal animals and plants. Chinese officials have promoted this as a way of guaranteeing supplies as well as protecting endangered species. And there have been some successes-notably with plant species, such as American ginseng-which is used as a general tonic and for chronic coughs. Red deer, too, have for centuries been farmed for their antlers, which are used to treat impotence and general fatigue. But growing your own is not a universal panacea. Some plants grow so slowly that cultivation in not economically viable. Animals such as musk deer may be difficult to farm, and so generate little profit. Seahorses are difficult to feed and plagued by disease in captivity. Other species cannot be cultivated at all. Even when it works, farming usually fails to match the scale of demand. Overall, cultivated TCM plants in China supply less than 20 per cent of the required 1.6 million tonnes per annum. Similarly, China's demand for animal products such as musk and pangolin scales far exceeds supply from captive-bred sources. Farming alone can never resolve conservation concerns, as government authorities and those who use Chinese medicine realise. For a start, consumers often prefer ingredients taken from the wild, believing them to be more potent. This is reflected in the price, with wild oriental ginseng fetching up to 32 times as much as cultivated plants. Then there are welfare concerns. Bear farming in China is particularly controversial. Around 7600 captive bears have their bile "milked" through tubes inserted into their gall bladders. According to Chinese officials, 10 000 wild bears would need to be killed each year to produce as much bile. But many Westerners argue that bear farming is cruel.

One alternative to farming involves replacing medical ingredients from threatened species with manufactured chemical compounds. In general, this sort of substitution is difficult to achieve because the active ingredient is often not known. In addition, most TCM uses compounds which may act synergistically-several ingredients may interact to give the required effect. Also, people prefer and trust the wild source. Tauro ursodeoxychohc acid, the active ingredient of bear bile, can be synthesised and is used by some Western doctors to treat gallstones, but many TCM consumers reject it as being inferior to the natural substance from wild [email protected]

Second choice

The search to replace medicines from threatened species with products from more abundant animals or plants may run into similar difficulties. In a survey in South Korea, 80 per cent of TCM practitioners surveyed said they considered bear bile more effective than bile from other animals. Three quarters of the doctors also believed that bear bile is better than the equivalent chemicals from plant sources. Similarly, some practitioners happily use substitutes for rhinoceros hom, while others stress its essential role in TCM. Even where substitutes are widely accepted, they may simply divert the problem. Peony and Madagascar periwinklealtematives to bear bile-are themselves threatened. So is the saiga antelope, whose hom was once proposed as a proxy for rhinoceros hom. Given the lack of knowledge about most species used in TCM, it is usually impossible to predict the ecological i.tnpact on substitute species. . People with a stake in TCM often seek chemical and biological altematives to endangered species because they realise that plants and animals lost from the wild are also lost to medicine forever. Sustainable and controlled use of natural resources are not just Western concepts. Chinese advice against overexploitation of natural medicinal soecies dates from at least Mencius, a philosopher living in the 4th century BC. As in the West, however, not everyone is conservation-minded. One Hong Kong wholesaler said there was no incentive to trade alternatives to threatened species because rare products are more profitable. Economic arguments also fuel opposition to trade controls. Bans on trade in rhinoceros hom and tiger bone have cost China's pharmaceuticals industry an estimated $2.5 million since 1993. Faced with evidence of increasing global demand for TCM sptcie's, many Western [email protected] are combative in discussi,ons @ with TCM [email protected] The Chinese, who commonly take a nonconfrontational approach, often view conservationists as rude and arrogant. Suggestions that TCM is hocus-pocus are particularly galling, given its successes; including those in the West. Westem misconceptions further strain relations. One repeated fallacy is that rhinoceros hom is used as an aphrodisiac in TCM. It is, in fact, prescribed for fife-threatening fevers and convulsions and has been clinically shown to have fever-reducing properties. Cultural differences add to the confusion. Chinese officials, for example, are puzzled by criticism of bear farming, which they view as a triumph in balancing the demands of wildlife conservation and the pharmaceuticals industry. Many Westerners, in turn, seem not to understand the importance of TCM, or the difficulties in substituting products. They also often fail to explain conservation threats to TCM traders and practitioners in terms that are believable and acceptable. Many still share the view of the Hong Kong trader who said: "There is no problem with turtles and tortoises. You only have to see how many there are in the markets. The problem is that there are not enough people to collect them in the countryside." Despite a history of mistrust and misunderstanding, communication is possible. Progress began in 1995 when representatives of the oriental medicine communities in Asia met with conservationists at a symposium in Hong Kong, organised by TRAFFIC. The two groups established a co clear willingness to cooperate through dialogue.' and mutual understanding. This has led to several bear imneetings, including last month's First International tened Symposium on Endangered Species Used in Traditional East Asian Medicine (see This Week, 20/27 December 1997, p 15). Ethnic Chinese fear that TCM itself may become an "endangered species" and are weary of it being made the intemational scapegoat for conservation problems. Wild animals and plants are under attack on many fronts. Rhinoceros hom is treasured for Yemeni dagger handles, deer musk used to be much sought after for Western perfumes, Buddhists sell turtles for the devout to release at temples, seahorses and newts are bought as pets. Add to this the increasing threat of habitat loss, and conservation efforts based on partnership rather than confrontation have never been so urgent.

Rob Parry-Jones is programme officer for TRAFFIC East Asia, based in Hong Kong Amanda Vincent is assistant professor of conservation biology at McG!ll University, Montreal, Canada


Endangered clouded leopard

Wildlife Traders Slow to Change their Spots New Scientist 31 Jan 98

EFFORTS to stamp out the illegal trade in endangered species suffered a blow last week with the disclosure that medicines containing body parts from tigers, rhinos and leopards are widely ava able across North America.

A survey by TRAFFIC-which monitors the trade in wildlife-of 110 Chinese stores in New York, Vancouver, Seattle, Toronto, San Francisco, Atlanta and Los Angeles found that half sold medicines containing, or claiming to contain, species in which it is illegal to trade. Almost all the medicines were made in China, which off i cially banned the manufacture and sale of til r and rhino derivatives in 1993. Judy Mills, director of TRAFFIC East Asia, asks: "Are these old stocks or has a black-market industry started up in China or elsewhere? The tiger and some rhino species are too close to extinction for us to be guessing at the answers."

Previous investigations by TRAFFIC uncovered tigerbone preparations for sale in Europe, Asia and Australasia, indicating that the illicit trade is taking cross the world. The organisation says inadequate legislation and poor rcement are to blame. n the US, for example, it is illegal to import products containing the parts of protected species. But customs must prove that products contain endangered animals before impounding them, even if they are labelled as such. Because foren sic techniques cannot detect derivatives such as ground-up tiger bone, there have en few prosecutions. And once a product has been imported it can be traded internally. TRAFFIC wants the US and Canada to make it illegal even to claim that a product contains endangered species. This is already the law in Britain, Hong Kong and China. Fiona Holland, Hong Kong