It has been estimated that we are losing 137 plant and animal species every single day. That's 50,000 species a year! Again, why should we in the Western world be concerned about the destruction of distant tropical rainforests? Because rainforest plants are complex chemical storehouses that contain many undiscovered biodynamic compounds with unrealized potential for use in modern medicine. We can gain access to these materials only if we study and conserve the species that contain them.
Key to Tomorrow's Cures?
Rainforests currently provide sources for one-fourth of today's medicines, and 70 percent of the plants found to have anticancer properties are found only in the rainforest. The rainforest and its immense undiscovered biodiversity hold the key to unlocking tomorrow's cures for devastating diseases. How many cures for devastating disease have we already lost?
Two drugs obtained from a rainforest plant known as the Madagascar periwinkle, now extinct in the wild due to deforestation of the Madagascar rainforest, have increased the chances of survival for children with leukemia from 20 percent to 80 percent. Think about it: eight out of ten children are now saved, rather than eight of ten children dying from leukemia. How many children have been spared and how many more will continue to be spared because of this single rainforest plant? What if we had failed to discover this one important plant among millions before human activities had led to its extinction? When our remaining rainforests are gone, the rare plants and animals will be lost forever-and so will the possible cures for diseases like cancer they can provide.
No one can challenge the fact that we are still largely dependent on plants for treating our ailments. Almost 90 percent of people in developing countries still rely on traditional medicine, based largely on different species of plants and animals, for their primary health care. In the United States, some 25 percent of prescriptions are filled with drugs whose active ingredients are extracted or derived from plants. By 1980 sales of these plant-based drugs in the United States amounted to some $4.5 billion annually. Worldwide sales of these plant-based drugs were estimated at $40 billion in 1990. Currently 121 prescription drugs sold worldwide come from plant-derived sources from only 90 species of plants. Still more drugs are derived from animals and microorganisms.
More than 25 percent of the active ingredients in today's cancer-fighting drugs come from organisms found only in the rainforest. The U.S. National Cancer Institute has identified more than 3,000 plants that are active against cancer cells, and 70 percent of these plants are found only in the rainforest. In the thousands of species of rainforest plants that have not been analyzed are many more thousands of unknown plant chemicals, many of which have evolved to protect the plants from diseases. These plant chemicals may well help us in our own ongoing struggle with constantly evolving pathogens, including bacteria, viruses, and fungi that are mutating against our mainstream drugs and becoming resistant to them. These pathogens cause serious diseases, including hepatitis, pneumonia, tuberculosis, and HIV, all of which are becoming more difficult to treat. Experts now believe that if there is a cure for cancer and even AIDS, it will probably be found in the rainforest.
Bio-prospecting
In 1983, there were no U.S. pharmaceutical manufacturers involved in research programs to discover new drugs or cures from plants. Today, more than 100 pharmaceutical companies, including giants like Merck, Abbott, Bristol-Myers Squibb, Eli Lilly, Monsanto, Smith-Kline Beecham, as well as several branches of the U.S. government, including the National Cancer Institute, are engaged in plant-based research projects trying to find possible drugs to treat infections, cancer, and AIDS. Most of this research is currently taking place in the rainforest in an industry that is now called "bioprospecting." This new pharmacological industry draws together an unlikely confederacy: plant collectors and anthropologists; ecologists and conservationists; natural product companies and nutritional supplement manufacturers; AIDS and cancer researchers; executives in the world's largest drug companies; and native indigenous shamans. They are part of a radical experiment: to preserve the world's rainforests by showing how much more valuable they are standing than cut down. And it is a race against a clock whose every tick means another acre of charred forest. Yet, it is also a race that pits one explorer against another, for those who score the first big hit in chemical bio-prospecting will secure wealth and a piece of scientific immortality.
In November 1991, Merck Pharmaceutical Company announced a landmark agreement to obtain samples of wild plants and animals for drug-screening purposes from Costa Rica's National Biodiversity Institute (INBio); the program is still ongoing today. Spurred by this and other biodiversity prospecting ventures, interest in the commercial value of plant genetic and biochemical resources is burgeoning today. While the Merck-INBio agreement provides a fascinating example of a private partnership that contributes to rural economic development, rainforest conservation, and technology transfer, virtually no precedent exists for national policies and legislation to govern and regulate what amounts to a brand new industry.
Since wealth and technology are as concentrated in most of the North as biodiversity and poverty are in much of the South, the question of equity is particularly hard to answer in ways that satisfy everyone with a stake in the outcome. The interests of bioprospecting corporations are not the same as those of people who live in a biodiversity "hot spot," many of them barely eking out a living. As the search for wild species whose genes can yield new medicines and better crops gathers momentum, these rich habitats also sport more and more bioprospectors. Like the nineteenth-century California gold rush or its present-day counterpart in Brazil, this "gene rush" could wreak havoc on ecosystems and the people living in or near them. Done properly, however, bioprospecting can bolster both economic and conservation goals while underpinning the medical and agricultural advances needed to combat disease and sustain growing populations.
The majority of our current plant-derived drugs were discovered by examining the traditional use of plants by the indigenous people who lived where the plants grew and flourished. History has shown that the situation with the rainforest is no different, and bio-prospectors now are working side by side with rainforest tribal shamans and herbal healers to learn the wealth of their plant knowledge and about the many uses of indigenous plants.
No comments:
Post a Comment