Some scientists believe only 1% of the worlds’ plant species have been screened for their medicinal potential. With more than 80,000 acres of tropical rainforest being lost everyday could many potential drugs be lost before the plants containing them are even discovered?
Drugs used to treat malaria, cancer and glaucoma all originally came from tropical forests.
In the same way colonial era plant hunters searched for new species to take home or exploit commercially, medical researchers explore tropical forests for cures and treatments in their diverse flora. However, this might not always be possible as tropical forests are chopped down.
According to the Scientific American, more than 80,000 acres of tropical rainforest and 135 species of plants and animals are lost daily. If current rates continue, the North Atlantic Space Agency’s (NASA) Earth Observatory predict the world’s rainforests will be gone within 100 years. Tropical forests cover less than 7% of the Earth’s surface yet are home to approximately 50% of all land animal and plant species.
Current extinction rates are 100-1,000 times higher than natural background rates and as many as 15,000 medicinal plants are under threat. This means humanity could potentially lose many future medical drugs contained within these plants.
Predictions vary, but only 1 –15% of plant species have been screened for their medicinal potential. This leaves out other potential uses such as a food or material. And one study estimated that 12.5% of plant species documented worldwide have medicinal value.
According to Milken Institute Review for every 10,000 compounds screened for medicinal properties, about 250 make it to clinical trials. Of those only one will eventually become an approved drug. Around 120 prescription drugs sold globally originate from rainforest plants.
Of anticancer drugs available between 1940 and 2002, 40% were from natural or naturally derived products.
Quinine, which is on the World Health Organisation’s (WHO) essential medicine list and used for treating malaria, comes from the bark of a Cinchona tree, found in the tropical forests of the Andes, South America. And from the Calabar bean, originating in the tropical forests of Africa, comes the drug Physostigmine, which is used to treat glaucoma (a condition where the nerve that connects your eye and brain becomes damaged and can lead to vision loss).
Biopiracy is when pharmaceutical companies use plants with medicinal properties identified by the indigenous people’s owners, for profit, without permission from them or compensating.
The most famous case of this is the plant Rosy periwinkle, native to Madagascar.
Rosy periwinkle’s original use as a traditional medicine prompted it to be investigated by scientists. Rosy periwinkle was found to have a chemical called Vincristine. Vincristine, also on the WHO’s essential medicine list, is used to treat different types of cancer, such as leukemia and Hodgkin’s disease.
Pharmaceutical company, Eli Lilly then patented and marketed the drug Vincristine, made billions and Madagascar never profited from it. However whether this in fact constitutes biopiracy is disputed because locals used Rosy periwinkle for a different medical use. And when Eli Lilly filed the patent Rosy Periwinkle had spread beyond Madagascar to other countries.
Harry Ridgewell is a WikiTribune journalist with a particular interest in science and politics. Follow @harryridgewell