Rhino horns are a precious commodity. On the black market, they can fetch an absurd price upwards of $60,000/kg. That’s more than the price of gold. Put in a different perspective, drop me a kilo of rhino horn and that pays two years of my graduate stipend…plus a Christmas bonus.* But that price also cost 618 rhinos their lives in 2012. This all-time high continues a rapidly increasing trend dating back to 2008 when poachers killed 83 rhinos–a noticeable uptick from the yearly average of 15 rhinos killed from 2000-2007. The practice is in no way humane, as poachers often cut horns off of tranquilized rhinos and then leave them to die from their wounds. I’ll spare you the grisly photos, but gruesome Internet images abound.
Fueling this demand for rhino horns are East Asian countries like China and Vietnam (I’m shaking my head in disapproval at you, my peoples in Vietnam). There, rhino horns are coveted by practitioners of traditional Chinese medicine who believe its extract can be used for treating fevers as well as other “conditions.” While most news coverage is quick to point out that rhino horns are little more than keratin (the protein found in our hair and nails) and that they lack any curative properties, little discussion is devoted to any actual research on their medicinal value. While published data is scarce–this probably reflects the obstacles in obtaining rhino horns for research–what little that has been published certainly doesn’t support using rhino horn as medicine.
In the early 1990s, Chinese researchers published in the Journal of Ethnopharmacology two studies that tested the ability of rhino horn extract to reduce fever (1,2). In the first study, researchers induced fever in rats by injecting them with turpentine oil, a known fever-causing agent. This was followed by injections of rhino horn extract prepared in either saline or in the herbal concoction traditionally prescribed for fevers. Both preparations of rhino horn extract were able to slightly decrease fevers in rats, but the effect required using rhino horn extract at 20 times the concentration normally prescribed by traditional medicine. Furthermore, the researchers observed that similarly high concentrations of horn extracts from saiga antelope, water buffalo, and cattle, also reduced fever in rats. This result meant that there was nothing special or magical about rhino horns in particular. The researchers concluded that, at least for the purpose of traditional medicine, rhino horns could be swapped out for horns from non-endangered animals.
Still, the Chinese studies had two other problems. First, they injected the rhino horn extract into the rats, whereas in traditional medicine rhino horn extract is ingested. Second, their study didn’t compare how effective rhino horn extract reduced fever against known anti-fever drugs. These issues were addressed by Laburn and Mitchell, who published their results in the Journal of Basic and Clinical Physiology and Pharmacology (3). In their study, rabbits were injected with bacterial lipopolysaccharide (LPS), a component of bacterial cell walls. Since LPS is foreign to the rabbit’s body, it triggers the rabbit’s immune system and induces fever. To test their fever-reducing abilities, either rhino horn extract, reedbuck (a non-endangered African antelope) horn extract, indomethacin (an anti-fever drug), or water was fed “gavage-style” to the LPS-injected rabbits. This meant that the samples were pumped directly into the rabbit’s stomach through a tube passed through its mouth. To monitor the effect of each agent on fever, rectal temperature was monitored over the course of 250 minutes. The researchers found that neither the rhino nor the reedbuck horn extract did anything to reduce fever in rabbits. More importantly, indomethacin was very effective at reducing the fever. These findings are similar to another report which found that acetaminophen was more effective than rhino horn extract at reducing fever in children.
Despite little scientific support for using rhino horns as medicine, the demand for rhino horns in China and Vietnam continues to soar. This week, in response to the growing poaching problem, Vietnam signed a no-poaching agreement with South Africa, where the majority of rhinos have been killed. Whether this will have any appreciable effect on poaching, however, is debatable considering that the demand for rhino horns in Vietnam has overshadowed its own conservation efforts. In 2010, the last of the Javan rhino subspecies native to Vietnam was killed by poachers.
Other ways to curb poaching have also been explored, such as routinely shaving off rhino horns. While rhino horns eventually grow back, this practice is unpopular among conservationists since rhinos depend on their horns for defense. It’s also worth noting that many dehorning advocates are also rhino owners whose true financial motives may lie in their support for legalizing the rhino horn trade. Another suggestion that’s been floated around to reduce poaching is to implant GPS devices into rhino horns. This would serve as a sort of RhinoJack that can be used to track down poachers. Others, on the other hand, suggest taking even more drastic actions.
These measures, of course, serve only to make poaching less desirable without dealing directly with demand. What’s troubling is that the demand for rhino horns is now being propped up by new and kookier, unscientific ideas, which extend far beyond its traditional use. Reports from China and Vietnam indicate that con men are peddling rhino horn extract as a miracle cure for whatever malady suits their fancy. As John Platt, of SciAm blogs, reports, “In Vietnam con men recently started marketing rhino horn as a cure for cancer or as a party drug to lessen the effects of alcohol.” (Do I smell a pseudo-cure for Asian Glow as well?) In other cases, rhino horns are being crushed and snorted like cocaine, sprinkled on food, or mixed with alcoholic cocktails as over-the-top displays of wealth popular among Vietnam’s “nouveaux riches.” By linking rhino horns with status symbols, the affluent are only driving up prices. Unfortunately for rhinos, as the price for their horns go up, so does the incentive for poachers.
*We don’t receive Christmas bonuses.
1. But PP, Lung LC, Tam YK. Ethnopharmacology of rhinoceros horn. I: Antipyretic
effects of rhinoceros horn and other animal horns. J Ethnopharmacol. 1990
Sep;30(2):157-68. PubMed PMID: 2255207.
2. But PP, Tam YK, Lung LC. Ethnopharmacology of rhinoceros horn. II: Antipyretic
effects of prescriptions containing rhinoceros horn or water buffalo horn. J
Ethnopharmacol. 1991 May-Jun;33(1-2):45-50. PubMed PMID: 1943172.
3. Laburn HP, Mitchell D. Extracts of rhinoceros horn are not antipyretic in
rabbits. J Basic Clin Physiol Pharmacol. 1997;8(1-2):1-11. PubMed PMID: 9363565.