Over the weekend, the Associated Press
picked up on a tragic story from Mozambique where dozens of people apparently died after drinking a traditional beer that had been laced, allegedly, with “crocodile bile
.” Radio Mozambique
updated the story this morning, confirming that 69 people have died and 196 are hospitalized
after attending a funeral on Friday in the village of Chitima in the western part of the country. The mourners had gathered later in the day in a neighborhood to drink Pombe
(or Phombe), a fermented mix of sorghum, bran, corn, and sugar. (Note: The Latin name for a yeast, not usually used in brewing, is Schizosaccharomyces pombe
.) The owner of the drink stand, her daughter, nephew, and four members of neighboring families were among the first seven fatalities received at the local hospital morgue on Saturday morning
Paula Bernardo, district director of Health, Women and Social Action in Cahora Bassa, told Radio Mozambique that as authorities attempted to determine the cause of these deaths, local hospitals became inundated with people suffering from diarrhea and muscle aches (roughly translated from Portuguese) and more people already dead. The patients came both from Chitima and the nearby village of Songo.
The provincial health director for Tete, Carla Mosse Lazarus, said that samples had already been sent to a national analytical laboratory to determine what poison or poisons had contaminated the 210-liter drum of the brewed beverage.
Oddly, nowhere in today’s Mozambique report is there any appearance or speculation that the toxic substance may have been “crocodile bile” or any other local names for such a poison (such as ndura). The very short Associated Press report that appeared yesterday in The New York Times cites another official, Alex Albertini, as being the source of this speculation.
If the poison is “crocodile bile,” what is it?
Crocodile bile is literally the digestive juice from the gall bladders of the Nile crocodile, Crocodylus niloticus. Its use traces back to witchcraft accusations in 1899, according to Professor N.Z. Nyazema, in the Department of Clinical Pharmacology at the University of Zimbabwe, writing in the Central African Journal of Medicine in 1984 and 1985. The university, in Harare, is about 300 miles southwest across the Mozambique border from where the poisonings occurred.
Bile contains detergent molecules, called bile salts or bile acids, that animals use to dissolve or emulsify fats. They also bind to hormone receptors that regulate their own production. But more simply, bile salts or bile acids could conceivably be quite toxic in very high concentrations, as would any strong detergent. However, this isn’t consistent with the amounts allegedly used in traditional poisoning cases.
Professor Nyzema explains,
It is widely believed that the bile from the gall bladder of a crocodile is very poisonous. The bile nduru is used as poison which is added to beer or stiff porridge, sadza, of an unsuspecting victim. It is not easy to buy this poison neither is it easy for anyone to kill a crocodile solely for the purpose of obtaining the bile. But with a good fee one can obtain some of the poison from a special n’anga [a traditional healer of the Zimbabwean Shona tribe]. At times the n’anga may undertake to poison the victim thus adding mystery to the ingredients of the poison. It is reported that the poisoning occurs at special occasions like beer drinking: The nduru is said to be introduced into the beer by dipping the finger or nail where a small amount is placed: This will suffice for the purpose. The unfortunate victim is supposed to die within 24 hours. The poison is supposed to manifest itself when the patient develops pains mainly in the abdomen.
Professor Nyazema learned these stories from the writings of Professor Michael Gelfand, a South African doctor who led the department in the middle of the 20th century and wrote extensively on colonial medicine in southeastern Africa.
This led Nyazema to question the veracity of these traditional stories and investigated the acute toxicity of a large dose of crocodile bile in twenty mice of both sexes using both water and alcohol extracts of the bile (he had the cooperation of the Kariba Crocodile Farm in providing ten gall bladders for the study). The mice were allowed to drink two concentrations of each type of bile solution for 7 days. He also dosed a single baboon.
None of the animals died or appeared to experience any signs of toxicity. The paper lacks any sophisticated pathology or blood chemistry, but the report seems adequate to conclude that crocodile bile is not the deadly constituent of so-called “crocodile bile” or nduru.
In the current tragedy in Mozambique, I can’t imagine just how much bile would’ve had to be added to 210 liters of brew for so many deaths to occur.
Professor Nyazema’s 30-year-old writings may provide the answer. He hypothesized that the traditional descriptions of this poison might be consistent with a toxic plant that may have been added to the brew in witchcraft practices. Nyazema seized on the observation that the chemical structure of bile acids are not that far removed from plant-derived cardiac glycosides, drugs like digoxin (Lanoxin) that are still used to aid patients with heart failure and some types of heart rhythm disturbances.
The cardiac glycosides, commonly called digitalis for the mixed plant extract, have a low therapeutic index – meaning that there’s a small margin between the beneficial therapeutic dose and the toxic dose. Plants like foxglove (Digitalis purpurea) are commonly found in southeastern Africa having escaped cultivation from European colonists, but Nyazema also lists 11 other species of local plants that contain similar cardiac glycosides.
While high doses of cardiac glycosides will obviously slow the heartbeat to zero, nausea, vomiting, abdominal discomfort, and diarrhea are among the coincident signs of cardiac glycoside poisoning. These are also consistent with the minimal descriptions provided by Mozambique health authorities.
Attempts to contact Professor Nyazema have been unsuccessful, but he was still publishing up until 2013. The analytical tests from this tragic episode will tell if the good professor was indeed correct about the source of this traditional poison. But the mystery may still remain: Who would do such a thing and why? http://www.forbes.com/sites/davidkro...lly-poisonous/ http://www.verdade.co.mz/nacional/51...amento-em-tete