| ECHOs Human health development notes |
CD-Rom editor’s note: This is a chapter concerning human health of the book "Ideas for Growing Food Under Difficult Conditions " a compilation of the first 51 Echo Development notes bulletin. This ECHO book is fully included in this cd-rom under the agriculture document. But the health tips in chapter are so useful that we want to add them separately here.
The book iswas compiled by Laura S. Meitzner and Martin L. Price
ECHO: North Fort Myers, Florida
For full inf and credit please consult the ECHO book under "agriculture"
SOME REFLECTIONS. No doubt the word "hunger" in ECHO's name leads people to think of hunger as ECHO's only concern. ECHO is involved in much more than alleviating hunger. I often tell people that even if no one was dying of starvation in the world, ECHO would still be ministering to the poor in the name of Christ. So would most of our readers. There is much more to life than not dying of hunger! It is the quality of life that is our concern, spiritual and physical--the same things for which we all work and pray for ourselves and our families. The following letter is an eloquent example of this greater need. (It is from Cesar Maes, a Belgian Catholic priest in Guatemala, and was forwarded to us by Mel West.)
"Our new fish pond is a source of joy. How important is entertainment for development projects? How important is it in the lives of well-off people? A project that only takes the stomach into account is crippled from the start. There is more in a human being than a stomach and one can still feel hungry in many ways even when well fed.
"Don Tomas had to wait 75 years for an opportunity to see fishes. He showed his plastic bag with some colored little carp. 'Look, Padrecito, how beautiful!' And he hurried home to his water pit. There are hundreds of pits and miniponds in a wide environment and uncountable are the children and adults having lots of fun with them. The fact that several carp are already the size of a frying pan increases the enthusiasm. People tenderly look at the fishes. They smile, and believe in God. Wonder is the most intimate relative of faith.
"Humble people dream around the fish pond. It took a lot of time to remove hundreds of tons of dirt, using wheelbarrows and primitive implements. It was worth-while. They had never seen swallows skimming the water, never felt the sensation of a quivering fishing rod when a fish wriggles at the hook, never seen a water lily, never miraculously stayed dry floating on water [in a boat]. Their delight is our joy. The model farm becomes with this huge pond an entertainment area especially for families. It is the only one in our highland.
"Healthy entertainment is scarce. This partially explains the alcohol abuses, the sexual deviations and the vulnerable family ties. It also explains the successful religious meetings where they do a lot of singing, usually mishandling guitars."
RESOURCE CENTER WELCOMES INQUIRIES FROM COMMUNITY HEALTH WORKERS. MAP International is a non-profit Christian global health organization providing donated medicines, medical supplies, and development training services to over 300 missions, denominations, and national church groups around the world. MAP's Learning Resource Center has a collection of helpful reference materials related to community health and development in the third world. Christians involved in health work in the third world are welcome to write to them for information difficult to obtain locally (much like ECHO addresses questions related to your agricultural work). A full-time librarian responds to requests for information with photocopies ($0.10/page), suggested readings, and recommendations from MAP's stock of publications for sale. On-site use of the resource center is also welcomed. Direct inquiries to Flor Oamil, Learning Resource Center, MAP International, 2200 Glynco Parkway, P.O. Box 215000, Brunswick, GA 31521-5000, USA; phone 912/265-6010; fax 912/265-6170.
THE APPROPRIATE TECHNOLOGY INSTITUTE (ATI) offers training modules at Providence Farm in North Carolina. ATI prepares missionaries to use technology appropriately as they assist in church planting movements. The 12-week courses run in the spring and are repeated in the early fall. The training is devoted to spiritual, cross-cultural, and technical preparation for overseas living in the areas of appropriate technologies, food production, and community health systems. Participants examine a holistic approach to development (sprinkled throughout the other courses) and experience community living in an isolated setting throughout the course. The extensive readings and the technical preparation in the curriculum cover most aspects of village living a missionary is likely to encounter overseas. Instructors for each module are highly qualified, and the learning is largely hands-on. Those not able to participate in the full curriculum can take one or more of the modules (each lasts about a month). Total cost for the full 12-week program is approximately $1500/couple, $850 single.
They also offer 2-week intensive courses in missionary medicine (in March, June, and November if classes fill). These are designed to prepare students to use the Village Medical Manual as a diagnostic tool for common health issues in developing countries. Total cost of the medical course is $362 per person. Write for other times and places the course will be offered. Contact ATI, P.O. Box 1126, Marion, NC 28752, USA; phone 704/738-3891; fax 704/738-3946.
MEDICAL AMBASSADORS INTERNATIONAL offers a program in Community Health Evangelism "developed and tested over many years to train people who want to establish a community-based health care program which also integrates evangelism and discipleship. We can also assist those who have already established their own program and want to integrate evangelism and discipleship components." They quote a past participant: "My organization talks about integration of physical and spiritual but they do not tell me how to do it. This training has given me the How-To's to help us establish such a work."
The one-week training in Colorado Springs is in October and costs $300 for room, board and tuition. Contact Missionary Internship, P.O. Box 50110, Colorado Springs, CO 80949; phone 209/524-0600; fax 209/571-3538.
HOW CONCERNED SHOULD I BE THAT LEAD MAY CONTAMINATE URBAN GARDENS? This question was asked by Craig Shuck with World Concern. I spoke with Dr. Nina Bassuk, the program director of Cornell University's Urban Horticulture Institute and asked her to give us a perspective on this question. There are two situations where lead may be a problem: (1) if you are gardening near a busy highway and (2) if you are planting in the rubble of a building in which lead paint had been used. Of the two, the second is the more serious. Dr. Bassuk said that there is no reason to panic over the question. If your entire diet is not from such a garden and children are over 6 years old, there is no reason for real concern. There would be some concern for children under 6 for whom a large portion of their diet came from a lead contaminated garden. However, if they play in the area, the hand to mouth ingestion of lead is far more serious. Plants naturally exclude most of the lead. She believes that contamination by cars would only be a serious problem for gardens planted quite close to cars on a busy highway.
She has developed a "cure" for such soils, based on experiments from urban gardens in New York City. The cure calls for adding large amounts of organic matter such as compost or manure and maintaining the pH near neutral. In soils containing large amounts of lead, organic matter representing at least 25% of the total volume may be needed. Lettuce grown in soils with 40-50% organic matter had zero lead uptake, even though the concentrations in the soil were as high as 3,000 ppm. The organic matter is more effective if it is well decomposed. When the pH drops below 6.0, the level of lead uptake increases. [However, that much organic matter should itself help buffer the pH.] Adjusting the pH to levels >6.5 is also effective against cadmium, another toxic heavy metal.
Leafy and root crops such as lettuce, spinach, potatoes and beets are likely to absorb lead. Crops grown for seed or fruit such as corn, tomatoes, beans, squash, eggplant and peppers normally do not absorb lead from soil in any appreciable amount. In spite of organic matter in the soil, plants near a busy highway can still become con- taminated as lead from exhaust is deposited directly on the leaves. Water removes only a small amount of the lead, but 1% vinegar added to the water or 0.5% dishwashing liquid removed it effectively. FUTURE FERTILITY: Transforming Human Waste into Human Wealth by John Beeby addresses a question many development workers face. "The soil here is so depleted and so few inputs are available. Is it safe to recycle human waste into our fields or gardens?" This book takes a careful look at the topic of processing human urine and manure so it may be safely added to the soil to sustain productivity. For those of you in areas where human waste is currently unmanaged and causes the spread of disease, this book may be very helpful in defining treatment options you could implement. Nine different methods for recycling manure (aquaculture, algae, solar heating, composting, trees, grains, etc.) are outlined and compared based on purification levels, resources required, and the value of the finished product as fertilizer. This book will answer many of your questions about how to manage a waste recycling system safely and effectively. The 164-page book is US$18.50 plus postage ($4.50 within the USA; others write for exact cost) from: Bountiful Gardens, 18001 Shafer Ranch Rd., Willits, CA 95490- 9626, USA.
MORINGA SEEDS USED IN WATER PURIFICATION. We learned of another use for the multipurpose tree Moringa oleifera from Dr. Samia Al Azharia Jahn with the Deutsche Gesellschaft fur Technische Zusammenarbeit (GTZ) in Germany. Suspensions of the ground seed of the moringa tree are used as primary coagulants to clarify Nile water. At high turbidities their action was almost as fast as that of alum, and at medium and low turbidities >30 FTU it was comparable with the optimum dose and proper stirring technique. The doses required did not exceed 250 mg/l.
Coagulating the solid matter in water so that it can be easily removed can remove a good portion of the suspended bacteria. "River water is always faecally polluted. At our sampling site the total coliforms amounted during the flood season to 1600-18,000 per 100 ml. Turbidity reductions to 10 FTU were achieved after one hour, reducing the coliforms to 1-200 per 100 ml. Good clarification is obtained if a small cloth bag filled with the powdered seeds of the moringa is swirled round in the turbid water." "With raw water turbidities below 30 FTU no satisfactory removal of suspended matter can be achieved unless the seed suspension is used in combination with alum."
The material can clarify not only highly turbid muddy water but also waters of medium and low turbidity which may appear milky and opaque or sometimes yellowish or greyish (showing annual turbidity fluctuations between 50-300 FTU, such as the White Nile or several African lakes). During the cool season, complete clarification, which takes only one hour in warmer water, may take two hours unless the water is left in the sun for some time to raise its temperature."
The number of seeds required for treatment depends on the local average weight of their white kernels, found to range from 130-320 mg in different clones. "In the case of the Blue Nile, for example, water of low turbidity in the initial and final flood season needs doses equivalent to about one quarter of a 200 mg seed per liter, water of medium turbidities needs half a seed per liter and at high turbidities the dose should be 1-1.5 seeds per liter." Water from a different river will require different quantities of clarifier because of variable characteristics of suspended material. Simple experiments in a jar will determine the best dose.
To prepare the seed for use as a coagulant, remove the seed coats and the "wings." The white kernel is then crushed to a powder, using a mortar or placing in a cloth on top of a stone and crushing. The powder should be mixed with a small amount of clear water (about a 2% suspension) in a small bottle. Close the bottle, then shake at least 5 minutes to obtain a good water extract. This milky extract is then poured through a tea strainer before being added to the turbid water. It is even better to put some thin clean wide-mesh cotton cloth on the strainer.
"The milky white suspension has to be added to the turbid water and stirred fast for at least one minute. If a wooden soup whisk is used, the nails sometimes present in these gadgets should be replaced by small wooden sticks. After that the floc will not form unless it is stirred slowly and regularly (15-20 rotations per minute) for about five minutes." "After stirring the treated water should be covered and left to settle for at least an hour." If moved or shaken before then, clarification will take much longer or fail to reach completion. The GTZ is planning implementation projects in Indonesia and Kenya. Dr. Jahn has retired, but you may still write her at GTZ, Abt. 414; Postfach 5180; D-65726 Eschborn, GERMANY.
Dr. Samia Al Azharia Jahn has written a 539-page book, Proper Use of African Natural Coagulants for Rural Water Supplies. (Chapter titles: Annual fluctuations in raw water quality, Water treatment with traditional plant coagulants, Special microbiological and toxicological studies on water purification, Cultivation of moringa trees, Introducing domestic water treatment to rural people, Practical guide to domestic water coagulation and hygienic water storage). Much of the book is devoted to moringa. French and Spanish translations are in preparation. The book may be available from the Deutsche Gesellschaft fur Technische Zusammenarbeit (GTZ) at the address above; fax 06196-79-73-17. Dr. Jahn has sent us seed for two related, more drought-tolerant species which, if we get them to produce, we will offer to you. Dr. Jahn would like to hear from you if you are working with moringa in a major way.
She also sent us an article from the East African Medical Journal that investigated whether water treated with moringa seed powder might be toxic to people. Pounded seeds were fed to rats for 6 weeks with no toxic effects. "As the plant material acts as a flocculent [makes solids come together and settle], one might assume that most of it will get trapped in the sediment and only easily dissolvable substances will be present in the water." Furthermore, moringa "seeds are used for food; they are roasted like peanuts, pounded for tea and curries are prepared from the green pods." [I have not heard of the mature dried seeds being eaten, and at least the variety we have is quite distasteful, so I wonder if these food uses are not all for green seeds.]
Dr. Mike Benge with the forestry department of AID has put together a 196-page photocopied compilation on moringa which he titles "Moringa: a Multipurpose Vegetable and Tree That Purifies Water." He wrote, "If you have people who would like this kind of information, just send their addresses." You should contact him at Agroforestry, G/ENV, Rm. 413-E, SA-18, Agency for International Development, Washington, D.C. 20523- 1812, USA; phone 703/875-4063; fax 703/875-4639; e-mail firstname.lastname@example.org.
USING MORINGA ON A LARGER SCALE. Use of moringa seed on a small scale (household level) to purify water has been mentioned. Dr. Geoff Folkard at the University of Leicester in England sent us articles concerning recent work in Malawi. "This is the first time that Moringa oleifera seed has been used as a primary coagulant [to clarify water in a treatment plant] at this scale (flow rate 16 m3 per hour)."
The water plant normally uses alum, an imported chemical, to clarify the water. They only had enough seed to run the plant six hours. Water quality was monitored before and after the switch from alum to moringa was made. There was no deterioration in performance. They used twice as much moringa as alum (50 mg/ml of moringa seed vs. 75 mg/ml).
Laboratory trials show that using alum and moringa together (they call it co-coagulation) can give superior results to either used alone. Moringa seed (either M. oleifera or M. stenopetala) was equivalent to alum and even superior in water of unusually high turbidity. (If you are interested in the chemistry involved, the active ingredients in moringa seed have been identified as two small water-soluble proteins with a net positive charge.)
"For many countries, imported alum is the major cost element in the provision of potable water. Malawi currently spends in excess of £220,000 each year on imported alum. Switching to moringa would both save foreign exchange and generate farm and employment income.
"Further full scale trials in Malawi are planned for January 1994. It is hoped that demonstrations for interested parties from other developing countries will be arranged." Dr. Folkard's address is University of Leicester, University Road, Leicester LE1 7RH, England. Write him for his 1995 technical reports if you have serious interest in large-scale water treatment.
Dr. Folkard is now working on extracting the oil from moringa seed. Preliminary tests indicate that the cake remaining after the oil is extracted is still able to clarify water. He is conducting further tests. Because the oil is quite valuable, this could have a big impact on the economic viability of a moringa-based water treatment program. A LIVING FENCE THAT MIGHT BE DEADLY? The following is based on a note in the October-December 1991 issue of Agroforestry Today, which in turn is based on an article in The Economist (July 6, 1991 pp 86-87) and The Lancet (May 30, 1987 pp 1257-58).
"Farmers near Kabale in Kenya describe traditions, now considered superstitious, that certain euphorbias cause cancer when planted near the homestead." [Euphorbias in Africa fill many of the environmental niches that are filled by cacti in the Americas.] Now the carcinogenic effects of one common living fence species, Euphorbia tirucalli, have been described. The active carcinogen has been found not only in the plant itself, but in extracts from nearby soil, vegetables and drinking water. "The report suggests that Burkitt's lymphoma, a common childhood cancer in East Africa, is caused in part by consumption of water and vegetables from sites near this euphorbia." The plant grows profusely in Kenya's Eastern, Western and Nyanza Provinces and in parts of Tanzania. In southwestern Uganda it is widely planted as a living fence to exclude livestock from protected springs, suggesting the frightening prospect that water that has been assumed safe is in fact very hazardous. It is also commonly used as a living fence to protect food crops.
TAKE A LESSON FROM THE DEER. I worked one summer in the laboratory of forage scientist Dr. VanSoest at Cornell University. He said we should learn a lesson from the deer. Deer can eat plants with no ill effect that are poisonous to cattle. The difference is that deer are browsers. They eat a small amount of one thing, then move on to many other things during the course of the day. In contrast, when a cow likes something it keeps eating. The body is capable of detoxifying small amounts of a great many things. This is sound advice to keep in mind when evaluating plant nutrition and toxicities.
I have thought of that many times since working with so many kinds of plants at ECHO. No doubt a steady diet of some would be harmful, as is the case with many common foods like cassava which contains cyanide or spinach with oxalates. There is a comforting degree of safety in "browsing" among a large selection of foods. Not only will your body more likely be able to detoxify the small amounts of any particular toxin, but it is more likely to find at least a minimal amount of the various nutrients it requires. All the more reason to work to bring diversity to the diets of people with whom we work.
A PERSPECTIVE ON NUTRITIONAL LIMITATIONS OF AMARANTH. (Excerpted from ECHO's Technical Note on amaranth.) Based on the content of nutrients, amaranth seed and leaves are exceptionally nutritious. Amounts of vitamin C, iron, carotene, calcium, folic acid and protein are especially high in the leaves. There are reports that the incidence of blindness in children due to poor nutrition has been reduced with the use of 50 to 100 g of amaranth leaves per day. On a dry weight basis, the protein content of the leaves is about 30%. Amaranth seeds have more protein than many grains (15%) and this protein is high in the amino acid lysine that is usually low in cereals, and sulfur-containing amino acids that are usually low in legumes. Based only on an analysis of those nutrients that are present, amaranth would seem to be almost a "miracle food."
The presence of rather high amounts of oxalic acid and nitrates place some limitation on the quantity of leaves that should be consumed daily. The amount of oxalic acid is roughly the same as that found in spinach and chard. Excessive amounts (over 100 g per day?) may result in a level of oxalic acid that begins to reduce the availability of calcium in humans. This is especially a concern if calcium intake levels are low to begin with. Nitrate in vegetable portions of amaranth is a concern because it is hypothesized that nitrates may be chemically changed in our digestive tracts into poisonous nitrosamines. Evidence for this is lacking at the present time. Nevertheless, over 100 g per day may be an unsafe amount to eat according to some scientists. The levels of both oxalic acid and nitrates are reduced by boiling the leaves like a spinach, then discarding the water.
The seed should be as nutritious as cow's milk or soybeans, based only on the quality and amount of protein present. But there are apparently some "anti-nutritional" factors in raw amaranth that lead to quite unexpected results in feeding trials. Performance is improved somewhat by cooking. For example, Dr. Peter Cheeke at the University of Oregon compared the rate of weight gain for rats on diet of corn and ground amaranth seed (Amaranthus hypochondriacus), either raw or cooked. The average daily gain for rats on the corn-soybean diet during the first 20 days was 3.9 grams. Rats fed the corn-amaranth diet gained on 0.3 grams per day. The average daily gain for rats fed corn and cooked amaranth was 1.6 grams. Raw amaranth seed is extremely unpalatable to rats (i.e. they will not eat it readily). This does not seem to be improved much by cooking. In another study, Dr. Cheeke found that after 11 days on corn-amaranth diet, rats "had an unthrifty, hunched-up appearance, and exhibited symptoms typical of semi-starvation."
I phoned Dr. Cheeke to get his perspective on the seriousness of these negative results. He told me that there are definitely toxins and/or anti- nutritional factors in the raw grain and that it is less of a problem with cooked grain. He said that a scientist in Australia has been feeding raw amaranth seed to poultry as the major component of the diet. He found that chickens went into spasms, convulsions, and finally died. This unidentified factor causes liver damage. Other problems are caused by saponins, including the unpalatability. But to keep this in perspective, Dr. Cheeke pointed out that there are few raw foodstuffs which do not have problems. Raw soybeans contain 10 kinds of toxins. Raw kidney beans will kill rats, but the problem is eliminated by cooking. The key seems to be to use the seed in moderate amounts and to cook it. I asked whether I could say that unless people had little other than amaranth to eat, there should be no problem. He thought that this was probably a fair statement. It is our opinion that more research needs to be done before we can recommend amaranth grain as a major ingredient in animal feed. To our knowledge it has not been shown whether these factors decrease the value of amaranth in human nutrition. It is quite possible that some varieties may lack these anti-nutritional factors. Until more work is done, however, the feeding trial results must moderate our otherwise enthusiastic promotion of amaranth grain. But remember, the Aztecs did quite well on at least selected varieties!
TOXIC PLANTS CONSUMED BY GOATS MAY AFFECT HUMANS WHO DRINK THEIR MILK. A reader sent us an interesting news note from the August 1983 issue of Popular Science. Dr. Donald Crosby at the University of California at Davis reported that a woman from a backwoods area had a deformed baby. Dr. Crosby noted a striking resemblance to the deformed limbs of calves born to cows that forage such toxic plants as lupines. Throughout her pregnancy, the woman had drunk milk from a goat that had foraged freely in an area where lupines are abundant. Dr. Crosby then fed lupine seeds to a goat and found dangerous levels of the toxins in the milk four hours later. The goat in question had also given birth to deformed offspring. The evidence is circumstantial, but persuasive. It is something you should keep in mind.
CAN PEACH PITS BE USED AS FOOD? Dennis Zehr wrote from Lesotho that they are blessed with an abundance of peach trees. The children eat the pits in limited quantity and they have been fed in limited amounts to chickens. He asked about their safety.
We passed the question on to Dr. Julia Morton. "As with certain varieties of lima bean and cassava, kernels of the peach, bitter almond, chokecherry, apricot and apple contain cyanogenic glycosides which, under certain conditions, release hydrogen cyanide gas. Some have caused human and animal fatalities when consumed in quantity. Pre-soaking and thorough cooking may render them safe for animal feed. But marketing would be a hazard as one would have no control of the manner in which they would be used. Peach kernels have been employed in homicide." It does not sound like it is worth the risk.
DO NOT EAT SPROUTED SORGHUM. You have heard of the added nutritional benefits that can come from sprouting seeds before eating them. Grain sorghum is an example of how it is not safe to assume that any edible seed can be eaten after sprouting. According to an article in Science News, this practice used to be recommended to improve the nutritional value of sorghum. The sprouts were eaten fresh or dried and ground into a meal. "The average fatal dose of HCN (cyanide) is 50 to 60 mg, and this amount was readily obtained from sprouts grown from 100 grams of sorghum seed. Consumption in a single meal of sorghum sprouts or the dried product derived from 100 g of seed is entirely possible." Dried sprouts retained the high levels of cyanide. The authors say this presents a special risk to people with chronic cyanide poisoning from diets high in cassava and sorghum grain. Sprouting could increase the already serious levels of cyanide in their diets by as much as 500 to 1000 fold. We now have the original research article and will share it with you if this is a matter of special concern.
IS VELVET BEAN SAFE TO EAT? [NOTE: Read the following articles to see the development of research's answer and current perspective on this question.] Velvet bean is generating so much interest and the pressure to use it for human food is considerable. The multiple uses of velvet bean (Mucuna spp.) as a green manure plant, for weed and erosion control and for moisture conservation has been discussed (see chapter on Soil Health). Its use in Central America is increasing rapidly. It is among the most frequently requested seed in ECHO's seedbank and others are starting to get excited too. For example, Felix Quero in the Philippines says, "What impresses us most is its aggressiveness. It could even compete with the problem grass Imperata cylindrica and has potential of at the same time controlling this grass and providing food."
Yet its safety as a human food is questionable. The book Food Legumes says the plants are mainly used for grazing although mature seeds are also fed to animals. "They are used mainly for feeding cattle or sheep [i.e. ruminants] and can only be fed to pigs if they constitute less than 25% of the diet. They are considered unsuitable for poultry." [This may not be as bad as it sounds if, as I presume, they are speaking of raw beans. You cannot feed very much raw soybean either and a raw kidney bean diet will kill rats.] "Velvet beans can be used as a human food but require considerable care in their preparation... In many parts of Africa and Asia they are regarded as a famine food. The toxic principle can be removed by boiling and soaking the seeds in several changes of water."
Their safety is a very important question. The vines produce beans abundantly. It would be a terrible waste to not use such a nutritious bean [28-32% protein] for human food unless it is indeed dangerous. For example, when I visited the World Neighbors project in Honduras last December a drought had destroyed the regular bean crop. Yet there was a heavy yield of velvet beans. Because velvet beans were all they had, I understand that the people were eating and enjoying them regularly. They boiled them with corn, removed the seed coats by hand, then ground equal amounts of beans and corn to make tortillas. I also enjoyed refried velvet beans there.
Roland Bunch reports that velvet bean coffee is becoming popular in their project area, where it is sold as "nutricafe." Daniel Salcedo's organization Pueblo to People wanted to market nutricafe in the States to provide income to small farmers in Honduras. He mentions that older people who have had trouble with coffee because it is diuretic (increases urination) love nutricafe, which does not have this effect. (The "nutri" part of the name is probably misleading. Daniel told me he had brewed nutricafe tested for protein and found little.) But if the toxic material is removed by boiling the beans and discarding the water, might this be a dangerous drink? Or does roasting the beans or the boiling process itself render it harmless?
TOXICITY. The instruction to "boil in several changes of water" does not provide perspective. The same warning could mean that velvet beans that are not so prepared could prove fatal with a single meal or that they would cause some slight symptom if consumed regularly for a year--or any degree in between.
The most likely toxic principle is L-dopa. Velvet beans contain so much L-dopa (6-9% of the dry weight of seeds with seed coats removed) that they are the primary natural source of this compound. It is one of the most effective drugs against Parkinson's disease. Neurophysiologist Dr. Judy Toronchuk tells us that L-dopa causes neurological symptoms. These can include hyperactivity, muscle spasms, cardiac irritability, hypotension and vasoconstriction. But it causes nausea at much lower doses. "So probably if people were to ingest the un-degraded L-dopa they would voluntarily stop eating it, due to nausea, before they had eaten enough to affect the brain."
Judy checked with a pharmacology professor. He felt that the L-dopa would break down sufficiently with cooking, particularly if cooked in water. It breaks down readily in the presence of moisture and forms the harmless pigment melanin. In fact the drug must be stored in dry, brown bottles which must not be allowed to exceed room temperature. (Might beans that have been stored for a year in the hot, humid tropics have less L-dopa than freshly harvested beans?)
There is also an unusual compound (a cyclic imino acid) that presumably is a natural derivative of L-dopa. The articles I reviewed mentioned no biological effect of this compound.
RESEARCH. This brings us to an aspect of ECHO's ministry that is not normally visible to our network. Many undergraduate programs require research as part of the science major. ECHO encourages such students and their professors to undertake projects that would benefit small farmers in the third world. One of the projects we suggested in our "Research Opportunities" write-up was to look into this question of safety of velvet bean. Senior premedical major Sarah Kramer and her advisor Dr. Bob Kistler at Bethel College in Minnesota did just that, and came up with some very interesting information.
First, a computerized literature search turned up two journal article reports of people eating velvet beans. One study mentioned that they found a village in Ghana where some people ate velvet bean daily. Another study found that rural people in southern Nigeria use it as a soup thickener by first boiling to remove the hard seed coat, then grinding it.
Tom Post in Belize forwarded us a report like none other I have encountered from the book Poisonous Plants of the United States and Canada by J. M. Kingsbury. Using the velvet bean grown in Florida years ago "even boiled for an extended time, the beans were unpalatable and produced, an hour or more after ingestion, symptoms of nausea and discomfort. While cooking, the beans gave off a volatile substance which produced a smarting sensation in the eyes and a pronounced headache among those experimenting with them." This is so unlike recent reports where the tropical velvet bean is being used that there must be considerable differences in toxicity between varieties. ECHO distributes two varieties of velvet beans. One is the kind that has no itch-producing fuzz on the pods and produces seed only during short days. We call it our "tropical velvet bean." That is the one we normally send overseas unless specified differently. Seeds may be white, mottled or colored. The other is the less vigorous kind grown in the southeastern USA which we call the 90-day velvet bean and is possibly the kind mentioned in this report. However, Sarah's experiments with mice described below were with this 90-day type and she found no such problems.
Sarah's computer search turned up a rat feeding trial in Ghana using velvet beans. Results were reported in terms of grams of weight gain per gram of protein eaten (the protein efficiency ratio or PER). Rats fed raw beans lost weight (PER -3.03). The PER for rats fed autoclaved (i.e. pressure cooked) beans was 2.31, and for rats fed only the ideal diet it was 3.41. The lower value for beans does not necessarily mean there was still some toxicity. The protein of many legumes is not always digestible, or may be lower in one of the essential amino acids than the ideal control diet. The latter appears to be the case here because rats fed autoclaved beans to which the amino acid methionine (which is often in inadequate supply in legume seeds) was added had a PER of 3.59.
A study in the States showed that the likely benefit to the plant of such a high concentration of L-dopa is protection of the seed. "Mature seeds of velvet bean are conspicuously free from attack by small mammals and insects." Small amounts of L-dopa that they added to an insect diet produced toxic effects. Concentrations as high as found in velvet bean seeds inhibited feeding completely.
THE FEEDING EXPERIMENT. Sarah did a 27-day feeding trial with mice. She used the 90-day variety of velvet bean because we did not have enough of the tropical kind to do a feeding trial. Four mice were assigned to each of 9 experiments. The control mice were fed commercial mouse chow. When an experimental diet was used, every third day 4.0 grams of the control diet (mouse chow) was added to provide nutrients missing in the experimental diet. This amount was chosen because that was the average daily amount eaten by rats fed only the control diet. Mice fed the control diet gained 8 grams. Mice fed the control plus the amino acid methionine gained 7.5 grams, which statistically was not significantly different at the 1% confidence level.
[A note to those not familiar with statistics. In everyday English we use the word "significant" about the same as the phrase "a lot." "A Mercedes is significantly more expensive than a Volkswagon" means it costs "a lot" more. A scientist uses the word differently. If the weight of rats in two experiments is "significantly" different we mean that statistically speaking the probability is small that random chance could have accounted for the results.]
EFFECT OF "NUTRICAFE." One set of mice was fed the control diet except that velvet bean coffee was the only thing available to drink. Beans were roasted at 300 F on a cookie sheet for one hour. To make coffee, 40 g of roasted beans were boiled in 700 ml of water for one hour. Mice gained 10.2 grams, which was not significantly different from the control.
EFFECT OF RAW VELVET BEANS. Mice fed raw beans lost 5.6 grams. With added methionine they lost 6 grams. This could be caused by the L-dopa, but so many harmful things occur in raw bean seeds that some other cause cannot be ruled out. This was significantly different from the control.
EFFECT OF BOILING THE BEANS. Beans that had been soaked with one change of water were boiled 30 minutes (40 g in 700 ml water) then another 30 minutes in fresh water. They gained 4.8 grams. Mice fed boiled beans with added methionine gained 3.8 grams. These were not significantly different from the control.
For your consideration, Doug Welch in Malawi wrote, "Velvet beans are consumed here. They were displayed at the trade fair as one of the beans produced for consumption. There is a story of how villagers fled when attacked and left some partially cooked velvet beans. The hungry raiders ate them and all died. They have to cook the beans twice."
EFFECT OF ROASTING THE BEANS. Mice fed beans roasted at 300 F on a cookie sheet for one hour gained 1.5 grams. Those fed roasted beans plus methionine gained 3.0 grams. Both were significantly less than the control but not than the cooked beans.
WHAT PERSPECTIVE CAN WE GIVE? There is not enough evidence to say with certainty that there are no problems from eating cooked velvet beans. We very much need more research, but human need does not wait for science. What should you recommend in the meantime? Considering everything that has been said above, if velvet beans were available and I was hungry or my diet was low in protein, I would definitely eat them after thorough cooking. If I were neither hungry nor malnourished, but was living at a subsistence level, I would occasionally eat velvet beans. (I am none of the above and do not eat velvet beans except as a curiosity if they are offered.) I would definitely eat modest servings at first, and consider changing my cooking methods if nausea occurred. I would warn families of possible symptoms and ask them to report any problems to me. I would not eat the wild velvet beans unless forced to do so and would be doubly cautious. The same would go for any new variety that I might obtain unless I knew that it was eaten elsewhere. I would feed them freely to pigs and chickens only if I had the firewood to cook them first. If at all possible I would "take a lesson from the deer" and browse small quantities of many foods, not eating too much of one thing.
New evidence has led us to offer the following guidelines at present. Has there been a failure of the bean crop in your area, but velvet beans are abundant? If so, it is almost certainly better to make use of velvet bean than to suffer hunger or protein malnutrition. Is the food situation a bit less desperate than that, but people still do not have enough to eat? If so, consider using velvet beans in moderation and not every day. Are there plenty of alternative sources of protein? If so, do not eat the velvet beans. Velvet bean cofffee has a lot of dopa in it. It should not be consumed regularly.
NEW INFORMATION ON THE TOXIC SUBSTANCE IN VELVET BEANS. Velvet beans are being grown more widely, because corn yields can be increased considerably by intercropping with velvet beans. Velvet beans have potential to be a significant food. Bean yields are high, sometimes when common beans fail due to drought. The beans are nutritious, with a high protein content. Many recipes have been developed for their use and people enjoy the taste. Herein lies a major dilemma for farmers and their advisors. About 5% of the weight of the bean is a psychoactive substance called "dopa." Dopa is still a commonly prescribed treatment for Parkinson's disease, though it has side effects such as uncontrolled muscle twitches and, in extreme cases, even psychotic disorders including schizophrenia.
Dr. Rolf Myhrman brought both good and bad news on the subject at ECHO's Conference for Agricultural Missions. In his lab at Judson College in Illinois, he has been studying dopa in velvet beans from different countries and after different methods of preparation for human consumption. One thought has been that one might get rid of the dopa by removing all the seed coats. This can be easily done by hand after cooking. However, Rolf was unable to detect any dopa in the seed coats.
One major use of velvet bean by humans is to make a coffee substitute. (The coffee is called "nutri cafe" in Central America and the bean is sometimes called "Nescafe bean.") Ideally, the dopa would either be destroyed by the heat or remain in the grounds, leaving the coffee free of dopa. Rolf found, on the contrary, that making "coffee" is an ideal way to extract intact dopa! "An 8-ounce cup of velvet bean coffee can be expected to contain between 250 and 300 mg of dopa. For comparison, a physician might start a Parkinson's patient on 500-1,000 mg of dopa per day." [The other side of the question is whether someone with Parkinson's disease, but who cannot afford prescription dopa, could drink velvet bean coffee as a treatment. Do any physicians in our network have ideas on this?]
Rolf is working closely with Dr. Dan Buckles at CIMMYT, the International Center for Improvement of Corn and Wheat. According to Dr. Buckles, many people in Ghana eat velvet beans most days, using them primarily as a soup thickener. People in Benin mix 10-30% velvet bean flour with corn meal. Various preparation techniques are being used and sent to Rolf for analysis.
The good news is that a large fraction of the dopa can be removed from beans by grinding and soaking in water. Simple detoxification techniques might soon be available to remove most of the dopa. "Soaking the powder in room-temperature water, even for only two minutes, removes over half of the dopa. A second two-minute soak removed another 29%. Eighty percent is removed in two short soaking periods." Soaking 5-10 minutes does not remove additional dopa.
Using 50 C water is no more effective than water at room temperature. However, soaking 5 minutes in boiling water removed 89% of the dopa and repeating the soak removed 99%.
Dr. Buckles sent Rolf velvet beans from a community in Ghana where people regularly eat velvet beans. Might these be extra low in dopa? Surprisingly, they had even more dopa than some others. Rolf suspected that they are detoxifying the beans and requested details of food preparation methods.
"We now understand how the Ghanians remove the dopa. They boil the beans 45-60 minutes, discard the water, add cool water and let the beans cool, then discard that water. Although our extraction techniques have all been with flour, it does not surprise me that they are removing a significant amount from whole beans by boiling."
You may contact Dr. Myhrman at fax 708/695-0407 or e-mail email@example.com. This work began when Rolf requested an ECHO publication called Hunger-Related Research Opportunities, which lists research projects that could be performed with a modest budget that would benefit peasant farmers.
SPANISH-ENGLISH VELVET BEAN RECIPES. Aware of all these cautions, some of you still may decide it is necessary to use velvet bean as a food source, if people are hungry or suffer from protein deficiencies and there are no other alternatives. When I visited the World Neighbors project in Honduras a few years ago they were in the midst of a drought. The crop of common beans had failed, but the velvet beans produced abundantly. This led to efforts to incorporate velvet bean into local recipes. Additionally, new recipes were developed based on their work with soybean, after changes to improve the taste and consistency.
Milton Flores of CIDICCO shares his own experience. "Although many people are eating the velvet bean in more than one way, we are careful to caution them to use it with care. We have observed symptoms such as drowsiness and headaches. This is especially true when people mix several [velvet bean] dishes at a time. In my own opinion, some people are more sensitive than others. I can stand only one cup of velvet bean coffee and one or two velvet bean tortillas at one time. When we have cooking demonstrations, with several dishes prepared and offered at the same time, it is usual that a couple people report symptoms like those I have mentioned. Most people, however, do not seem to be affected in any way."
A recipe book can make everything look very straightforward and safe. Eating velvet bean has not been proven to be safe, but it is safer than trying to live without protein. (I imagine other beans could be made to fit into these interesting recipes.) World Neighbors/ACORDE has made available the Spanish-English recipe book Nutri-Cocina/Nutri-Kitchen. It gives guidelines for using seeds of this productive green manure crop to prepare 23 foods. The toasted nutri-flour and mashed cooked beans are used to prepare hot, high-protein drinks, tortillas, doughnuts, ravioli, pasta, and several sweet cakes and desserts. Ingredients are simple and common, and the directions are complete and easy to follow. You can order the book for US$7 plus postage: $3 in US/$7 overseas, from World Neighbors, 4127 NW 122 St., Oklahoma City, OK 73120-8869, USA; phone 405/752-9700; fax 405/752-9393; e-mail firstname.lastname@example.org. If you are in Central America, contact the regional office of Vecinos Mundiales, Aptdo. Postal 3385, Tegucigalpa, HONDURAS; tel/fax (504) 32-7471. They are an excellent source of information on the uses of velvet bean in Central America.
ARE JACK BEANS SAFE TO EAT? I have become uneasy recently. I can tell by letters that some of you are excited at the human food potential of the large seeds from the high-yielding jack beans (Canavalia ensiformis) that we sent. They are edible, but read the following cautions carefully. (You may react like one reader who was frustrated at my discussion of whether velvet beans are safe to eat. He wanted to know either "yes" or "no." Unfortunately, the world is often ambiguous.)
The book Food Legumes says, "The mature dry seeds can be used as food, but are not popular because of their unattractive flavor and texture, and the fact that they require soaking and boiling in salt water for several hours to remove the toxic constituents and to soften them. [Ed: Flavor and texture might be less of a problem if beans were just one ingredient in a recipe.] In Indonesia they are often boiled twice, left in running water for 2 days after the removal of the seed-coat, then fermented 3-4 days and finally cooked once more." "Dried seeds can be used in livestock feed, but are not very palatable and can cause outbreaks of poisoning unless cooked or limited to less than 30% of the total feed."
Legumes in Human Nutrition says "the flowers, leaves and immature pods and seeds are used as vegetables." The Handbook of Tropical Food Crops says, "Foliage and seeds often contain poisonous substances and these have been implicated in occasional fatal poisonings. ...Apparently the amounts of poisonous substances vary with age of plant, maturity of seed, and possibly with environmental factors. Some varieties contain such small quantities of poisonous substances that they are commonly eaten and are considered harmless. There is no easy way to distinguish poisonous from nonpoisonous varieties. The commonly used varieties are not dangerously poisonous, judging from their popular usage."
Roland Bunch in Honduras says to "make sure people boil the bean and change the water twice. This means there will be an extra expense in firewood, but it is necessary to prevent ... problems." Tom Post in Belize says people there cut the immature pods into pieces and serve them in soups.
Young jack bean pods can be eaten as a vegetable without any special precautions. Allen Voelkel wrote from Mexico, "I received approximately nine jack bean seeds. These I planted around the school. Some of the plants got destroyed, others were neglected but, year after year, the plants continued to pop up around the place. I was tremendously impressed by their resistance to drought. At the time, they were the only green thing in sight for miles, and they were one of the few plants that could withstand the ever devouring leaf-cutter ants. One of our workers took some of the seeds out to a community and showed a family how to plant and, then later, to prepare [the young pods] to eat. The family loved them, and they continue to grow them as a garden vegetable. Apparently other families are now interested."
A CAUTION ABOUT USING MORINGA TREE ROOTS AS A HORSERADISH SUBSTITUTE. An extensive review of uses of the moringa tree, written by Dr. Julia Morton, appeared in Economic Botany. I thought I should bring one paragraph to your attention.
"The root, best known in India and the Far East, is extremely pungent. When the plant is only 60 cm tall, it can be pulled up, its root scraped, ground up and vinegar and salt added to make a popular condiment much like true horseradish. ...The root bark must be completely removed since it contains two alkaloids allied to ephedrine-- benzylamine (moringine), which is not physiologically active, and the toxic moringinine which acts on the sympathetic nerve endings as well as on the cardiac and smooth muscles all over the body. Also present is the potent antibiotic and fungicide, pterygospermin. The alkaloid, spirachin (a nerve paralyzant) has been found in the roots.... Even when free of bark, the condiment, in excess, may be harmful." The key words are "in excess": take a lesson from the deer (see above).
WHERE THERE IS NO DOCTOR AND OTHER RESOURCES. This book by David Werner is so widely used that most of you in the field probably already have a copy. An extremely useful health handbook for villages, it includes helpful signs in diagnosis and simple, basic treatments common in tropical situations. It is readable and easy to use, and would be a useful tool in health teaching. Copies are available at bookstores around the world and in several languages. If you cannot find it locally, write The Hesperian Foundation, P.O. Box 1692, Palo Alto, CA 94302, USA. You may also want to use other books in the same style and level of practicality: Where There is No Dentist, Disabled Village Children, and Helping Health Workers Learn. These are all handbooks which are both interesting and immediately applicable in your work.
VITAMIN A USED IN TREATMENT OF MEASLES. Don Mansfield with William Carey International University brought the following item in the Footsteps newsletter to our attention. "Children with severe measles do benefit from having a capsule of vitamin A. Two studies from South Africa and Tanzania have shown that childhood mortality from measles can be reduced by about 30% if a capsule of 200,000 is given on each of two successive days. In fact, the World Health Organization recommends that this should be the routine management of measles where there is obvious vitamin A deficiency or where the proportion of children dying from episodes of measles exceeds 1%."
Don adds, "In Mali we had kids die every year from measles. We had hundreds of bottles of vitamin A that had been donated. JoAnn just never knew to use it for measles. Maybe EDN can help get the word out to remote mission clinics."
ELECTRIC SHOCK AS FIRST AID FOR POISONOUS BITES. I received the following account of scorpion bites from Don and JoAnn Mansfield in Mali. Don works in agriculture; JoAnn runs the clinic.
"The missionary I replaced had told me how to treat scorpion stings with a pair of 'electric shockers.' Frankly I did not believe it. Three weeks after we arrived a woman we knew came to the clinic. She had been stung on the side of her foot by a BIG scorpion of the kind that are common here. She was bent over with pain. We had nothing but an antihistamine, which did not help. I told her about the shock treatment. She was in so much pain that she was willing to try anything.
"We could not find the equipment my predecessor had told me about, but we did have a Briggs and Stratton power plant. I put the metal portion of the spark plug wire right on the spot where she had been stung, and had someone pull the rope. She jerked, but kept on moaning, hardly noticing the shock. The second pull had the same result. After the third pull she immediately straightened up, stopped moaning and began to leave. I stopped her and asked about the pain. She had none.
"In the next couple years we treated 4 or 5 more people similarly. In one case, where the sting was in a difficult spot to shock, there was still pain although it was a lot better. The others had total relief from pain, sometimes with one pull. None took more than three pulls."
Research into treating poisonous bites with electric shock began with Dr. Ron Guderian, a missionary in Ecuador, wondering about a widespread notion in Ecuador that electricity was therapeutic for snakebite. We wrote to Dr. Guderian for an update. A summary of his comments follow:
"In the laboratory we are trying to determine how the electric shock actually deactivates the venom, or what protein components the shock affects and how. This would give us the scientific basis to say how the shock works, not just that it appears to on trial." [The electric field changes the three-dimensional structure of the toxin, converting the venom to inert material. The shock eliminates the venom's biological activity.]
"We have been using the electric shock as a first aid measure for snake bites in Ecuador since 1980 and have found some very interesting results. If the shock treatment is given at the site of the bite and in an appropriate time frame, there is no reaction on the part of the person bitten." Shock has been used as first aid on the venomous bites of Portuguese men-of-war, Conga ants, scorpions, spiders, and even poison oak. It is used for snakes with hemotoxic venom which destroys blood cells and coagulation proteins, and does not have the same action on neurotoxic snakes (such as the cobra, mamba, and coral snakes).
"In the past two months we have treated several patients who have come to us 4-6 hours after being bitten. The site of the bite and surrounding tissues were edematous [Ed: in other words, venom had definitely been injected]. Having no other resource, the electric shock was given on the chance that it might help in some manner [Ed: Even though shock treatment is normally done much sooner than 4-6 hours]. To our surprise, the swelling decreased and in three days the site of the bite and surrounding tissues were normal. Without treatment, swelling usually increases and can last for weeks. The reduction is important because swelling causes much of the secondary complications from snake bites." In addition, the shock kills the anaerobic bacteria present in the bite which can lead to tissue death on the site.
THIS IS ONLY FOR USE IN REMOTE LOCATIONS WHERE ANTI-VENOM IS NOT AVAILABLE. "To answer your question, yes, shock should be used only if anti-venom is not available. Shock is not used along with anti-venom, nor in place of it. I have recorded 353 reports [by 1995] of the use of electrical shock with positive results."
TECHNICAL DETAILS. NEVER USE CURRENT FROM THE POWER COMPANY OR ALTERNATING CURRENT FROM YOUR OWN GENERATORS! "You need a DC pulsating electric current, 20-25 Kv and only milliamps of current. [An AC current can affect the heart; DC does not.] The best source of shock that we have found is the spark plug of an auxiliary gas motor such as a chain saw, motorcycle or outboard motor. Shock can also be applied directly from the coil of a car. Again let me say that this is experimental. The most important concept is that the patient be treated as soon as possible, preferably within 10-20 minutes. Otherwise permanent tissue damage may have already occurred.
"Most snake bites occur on the limbs. Ground the limb on the side opposite the bite. Hold the electrodes in place with tape as contact is otherwise broken during the discharge. Apply the shock directly to the bite for 2 seconds, rest and repeat 2- 3 times depending on the size of the snake." [Don Stilwell with SIM sent us a summary of a conversation with Dr. Guderian saying that the larger and more potent the snake and the more venom injected, the more shocks may be necessary, even up to eight discharges.]
To be effective, the skin should be washed (with alcohol, if available) and dried; sweat is a good conductor. Ground the plate on the opposite side of the bite and apply the shock on the bite marks for best penetration of the skin (skin is very resistant, and 15,000-20,000 volts are needed to penetrate it). After this first aid is applied, send the patient to a medical center for evaluation. They should take 2 cc's of blood and put it in a clear tube undisturbed for 20 minutes. Tilt after 20 minutes; if a clot has formed, the patient should be fine. Repeat this test every 6 hours for 48 hours, and if clots still form, the patient may go home. If clots do not form, give antivenom; this may be necessary if treatment is delayed.
Dr. Guderian requests that, if you use this method, please keep a record of patients treated and note the type and location of bite, type of snake, time elapse between bite and treatment, source for current and patient's response. "Since we are still collecting data to prove that this method works in other parts of the world, I would appreciate receiving any such data." His address is Hospital Vozandes, HCJB Casilla 17-17-691, Quito, ECUADOR, South America; fax 593-2-447-263; e-mail email@example.com. ECHO would like to know your results too.
REACTION TO BEE STINGS. The July 1987 issue of Florida's cooperative extension service bulletin on beekeeping, Apis, dedicated all four pages to the subject of reaction to bee stings (ask for a copy if you are very interested). The facts are even subject to controversy in the medical profession. The normal "local" reaction is "pain, swelling, redness, and itching... [such people are] at little risk of death unless the mouth or throat is affected so that the respiratory tract is obstructed." "Many people continue to believe that because they swell up they are at risk of losing their life when stung by bees. Ironically, it may in fact be the reverse. Those far more at risk may show no reactions to stings at all." It is systemic or allergic reactions that can be life-threatening. "There is no evidence that the very few who die as a result of a bee sting come from the pool of those who once before sustained a systemic reaction. On the contrary, no reaction at all may be a more ominous predictor of a lethal outcome on a subsequent sting." Stings inside the mouth and on the eyeball require special attention and are so very serious that when working with bees a veil should always be worn.
Death usually comes from multiple causes, not simple anaphylactic shock or allergy. In fact, most allergic reactions are in children, while 90% of those who die of bee stings are over age 25. "One may readily see how (1) a hot summer day, plus (2) strenuous exercise, plus (3) coronary atherosclerosis, plus (4) a bee may add up to death, whether or not one invokes an allergic mechanism...." "Panic by the person stung or those around him/her can produce a systemic reaction in itself." "The frightening aspect of being stung cannot be ruled out as a cause of a systemic reaction. A patient who suddenly develops hives, shortness of breath (sometimes with bronchospasm) and giddiness ... is terrified, as are those about him. The patient may think he is going to die, as may his family or physician. What people need to know is that the vast majority of patients, particularly if aged under 25, will quickly recover. ... patients who have these terrifying experiences need to know that there is no evidence either that they came to the brink of death or that they are at greater risk of dying from a subsequent sting than anyone else."
The conclusion: "the risk of fatality ... is lower than previously thought. What must be emphasized, however, is that environmental factors and physical well being of the individual being stung cannot be ignored when judging who is at risk of dying from a bee sting. Nor can perceptions by the individual being stung. Panic by the person stung or those around him/her can produce a systemic reaction in itself.
IS THE AFRICANIZED BEE STING MORE LETHAL THAN THAT OF ITALIAN BEES? David Unander sent us a report in Nature which concluded that the lethality of Africanized ("killer") bees is entirely due to their tendency to attack in mass. In South and Central America colony defenses result in attacks during which thousands of stings may be inflicted on one individual. "Although attacks of 300-500 stings have been survived without treatment, more than 500 stings are commonly fatal." Venom was collected from worker honeybees in Arizona and Africanized bees in Costa Rica. Analysis of venom pooled from 1,000 bees of each type showed that European bees contained more venom (145 micrograms dry weight) than the smaller Africanized bees (94 micrograms). In a trial with mice, the lethal dose for the purified venom was identical for both kinds of bees with one strain of mice. For the other strain of mice, the dose of Africanized bee venom required to have the same effect as honeybee venom was considerably higher (7.1 vs 4.6 mg/kg).
DO MOSQUITOES CARRY THE AIDS VIRUS? In case you are worrying about this frequent rumor, the following is quoted from World Development Forum, November, 1986. "The Pasteur Institute's Jean-Claude Chermann, a co-discoverer of the AIDS virus in 1983, says they do. A study in Zaire of 50 insects, reports Asia Week, indicated that all--including mosquitoes, tsetse flies and cockroaches--were infected. But the reassuring news is that the 'insects don't carry nearly enough of the virus to infect a human.' There is no way, he said, that the virus could be transmitted to humans by mosquitoes or other insects."
NEWSLETTER ON AIDS in Latin America. BoletÃn SIDA is a Spanish language bulletin published three times a year by MAP-Latin America. "We have produced this bulletin to inform the Evangelical churches in Latin America about the advance of the disease, its consequences, the methods of prevention, treatment and accompanying emotional issues for those affected. We hope to stimulate the church to take part in the struggle against AIDS." To subscribe (no charge, but donations welcome) send them your name and address. Also mention the kind of work you do and whether your work currently involves you in AIDS issues. Write MAP, BoletÃn SIDA, Casilla 17-08-8184, Quito, ECUADOR; phone (593-2) 452-373; fax (593-2) 435-500.
MALARIA VACCINE WITH ARTEMISIA. Because malaria is caused by a protozoan (a small animal) rather than bacteria or a virus, a vaccine has been difficult to develop. Experiments in Colombia suggest that it may be possible, however. They synthesized several polypeptides which are identical to segments of proteins on the protozoan. (Proteins are very large polypeptides.) Monkeys inoculated with the right mixture of these polypeptides developed partial to complete immunity to malaria. It has not yet been tried in humans. If you want a copy of the article let us know. (It is pretty heavy biochemistry.)
The following is abstracted from World Watch, May/June 1994. "More than 20 years ago Chinese scientists confirmed the antimalarial qualities of artemisinin, ... extracted from a fern- like plant Artemisia annua." This plant has been used as an anti-malarial drug for more than 1,500 years. Now derivatives of artemisinin that can be taken orally or injected have been developed and are widely used in Southeast Asia, and in parts of Africa and Latin America. The injectable form acts more rapidly than any other antimalarial and is effective against multi- drug-resistant parasites. It is not yet approved in any developed country.
The article in World Watch says that clinical trials have now been done and that "40-66% of participants were protected from the most common and deadly strain, Plasmodium falciparum, which is responsible for 95% of malaria cases." "Although Patarroyo's initial field trials were criticized because they did not meet international protocols, he answered their skepticism by conducting trials that did meet those standards. One of those trials, completed in 1992 in Ecuador, showed that the vaccine was successful in protecting 66% of the volunteers from the common malaria strain." It has been tested on 41,000 people in South America. Finally the World Health Organization and the Walter Reed Army Institute of Research are beginning tests in Africa and Asia.
"Meanwhile, other researchers are ... studying the feasibility of altering the mosquito's genetic makeup so that it will be unable to carry and transmit the parasite to humans." [Presumably this mosquito would compete with normal mosquitos for food and breeding grounds, so the number capable of infecting people would drop.]
HOMEMADE MOSQUITO REPELLENT FROM NEEM. Dr. V.P. Sharma, Director of the Malaria Research Centre in New Delhi, says the repellent is particularly effective against the Anopheles mosquito which spreads malaria. When the preparation is applied to the body, mosquitoes are effectively repelled. Low-cost neem oil is mixed with coconut oil in concentrations of 1-2%. This information is taken from Neem News, vol 1, p. 4, published by the Neem Association, 1511 Oneco Ave., Winter Park, FL 32789, USA. The non-profit association is organized to promote communication between neem scientists, growers and producers; promote its various uses and seek other uses; promote research to develop superior varieties of neem and to develop new uses.
POTENTIAL CONTRACEPTIVE FROM NEEM TREE OIL. I do not normally include items in EDN that are not yet ready for use. Because we have mentioned neem so often, though, I thought you would be interested in this item taken from Agroforestry Today. Indian scientists have isolated a neem oil extract which they believe can be refined into a birth control agent for women. They report it has spermicidal qualities and also can prevent a fertilized egg from being implanted in the uterus, possibly by interfering with estrogens. Unfortunately their "ultimate aim is to refine it into a powder that can be synthesized in the laboratory." I hope someone follows up to see whether a technique might be developed for making contraceptives directly from neem in a simple laboratory that could be set up anywhere.
ORAL VACCINE FOR TYPHOID. When I think of typhoid shots I think of finding time for three trips to a doctor, major soreness and some fever. A trip that comes up suddenly often does not allow time for completing the series. So when Glen Munro told me that he was immunized with no noticeable side effects by taking four pills, one every other day, I asked for details. He said the immunity is supposed to last 5 years. The series cost him $30. It is a live vaccine and must be refrigerated at all times. It is manufactured by the Swiss Serum and Vaccine Inst., Berne, Switzerland. I contacted Andy Murai at their U.S. subsidiary, Berna Products Corporation, 4216 Ponce de Leon Blvd., Coral Gables, FL 33146; phone 800/533-5899 or 305/443-2900; fax 305/567-1043. He said they are glad to ship overseas, even if orders are small.
EFFECTIVENESS OF A MORINGA SEED EXTRACT IN TREATING A SKIN INFECTION. There are powerful antibiotic and fungicidal effects of pterygospermin from the flowers and roots of the moringa tree. Now Axel Bosselmann has brought to our attention a study by Drs. Caceres and Lopez at the University of San Carlos in Guatemala. The article is summarized below.
Herbal applications are commonly used to treat skin infections in developing countries, although few investigations are conducted to validate scientifically their popular use. The small drought-resistant Moringa oleifera tree produces edible leaves, pods, flowers and roots. A previous study had showed that seeds are effective against skin infecting bacteria Staphylococcus aureus and Pseudomonas aeruginosa in vitro (i.e. in a test tube). This study showed that mice infected with S. aureus recovered as quickly with a specially prepared aqueous extract of moringa seed as with the antibiotic neomycin.
This study proves only the effectiveness of moringa as they prepared it. That preparation could be done in any country, but not with just household utensils. It was prepared by infusing 10 g powdered moringa seeds in 100 ml of 45 C water for 2 hours. The part that is a bit more complicated is reducing the 100 ml down to 10 ml by placing it in a rotavaporator. This is a very common piece of laboratory equipment which continually rotates a flask containing the liquid. An aspirator attached to a faucet produces a modest vacuum when the water is turned on. A rubber tube from the aspirator is connected to the rotavaporator, reducing the pressure and causing the water to evaporate rather quickly without boiling it. The ointment was prepared by placing 10% of the extract in vaseline. (We can send a copy of the article to medical personnel.)
Are you in a situation where there is a shortage of antibiotics? This ointment could be prepared for use in the local community anyplace where there is electricity and running water. I would not be surprised if much simpler methods, better suited to preparation as needed in the home, might not also be effective. I hope someone will devise and test such preparations.
USING NEEM LEAVES TO TREAT SCABIES. Larry Radice, of Maryknoll Fathers and Brothers in Tanzania, wrote, "After reading in EDN about use of moringa to treat a skin infection, I thought I might share with you and your readers my experience using neem tree leaves to treat scabies. (Scabies, also called seven year itch, is especially common in children. It causes very itchy little bumps that can appear all over the body, but are most common between fingers, on wrists, the waist and genitals. It is caused by little animals similar to tiny ticks or chiggers, which tunnel under the skin.)
"I lived in Tanzania for almost 8 years. One day while visiting a friend's home I noticed his daughter had a very bad case of scabies. ... I was told that she had gone to the local clinic, bought some medicine, but it had run out and the scabies had not cleared up. ... Her scalp was horribly encrusted and she had no hair in the infected area.
"I knew that neem tree leaves had insecticidal properties and that scabies is caused by a small mite. So I thought it would be worth a try.... I had the mother take neem tree leaves, about a hand full, and pound them into a mush adding a bit of water. I believe she then heated this, boiling off the excess water and leaving a paste. I told her to apply the poultice to the infected area twice a day for five days, leaving it to dry on the scalp.
"When I visited the home again two weeks later I had hardly said hello before she was excitedly telling me that her daughter was well. In fact by the third day the scabies was drying and by the end of that first week she could see new hair growing. When I saw the child the scabies were gone. I suggested the cure two other times and in both cases I later heard that the scabies had cleared up, but I did not get to see those results for myself."
In response to this letter, Dr. S. X. Charles at the Medical and Cancer Research and Treatment Center in India sent us the results of a study of 814 people treated with neem and turmeric. Scabies is normally treated with a scrub bath, boiling the fomites (clothes and bed linens), and application of benzyl benzoate. "The drug caused skin reaction when rubbed on the face, and children accidentally rubbing it ... in the eyes was common." Where There is No Doctor recommends a homemade but dangerous alternative to those who cannot afford the benzyl benzoate. In this, the very toxic insecticide lindane is mixed with 15 parts of vaseline. The neem method is far less toxic and essentially free.
"Fresh neem leaves and turmeric are ground to a paste in the proportion of 4:1 by weight. The measurement that is taught to mothers is a handful of neem leaves and a piece of turmeric ½ the length of the index finger. This paste is rubbed all over the body and left to dry. The procedure is repeated daily until the patient is cured. (Boiling clothes and scrub bath is carried out daily before application of the paste.)
"Paste rubbed on the face has not caused any skin reaction or other toxic symptoms. Because of the bitter taste, chances of children swallowing it was remote, and even if swallowed [is not toxic]." "Of the 824 cases, 98% showed complete cure within 3-15 days of treatment. Those cases (95.8%) with localized lesions showed cure in 3-5 days. When lesions were all over the body and there was secondary infection, treatment needed for a cure was 6-15 days. Failure of treatment was only 2%. The reasons for failure were irregular application of paste and not doing the preliminary treatment of scrub bath and boiling of fomites to prevent reinfection."
HONEY AS A DRESSING FOR WOUNDS. (Based on an article in the October 1992 issue of Apis.) New Zealand bee scientist Dr. Peter Molan says that "honey is used in many countries in the treatment of burns, blisters, bed sores and major wounds. Honey has long been used as a wound dressing and is probably the perfect substance for such a use. Not only is it antibiotic (killing almost all bacteria), it also keeps the wound from dehydrating. Almost all other wound dressings either keep the wound dry (avoiding infection, but leading to scarring), or moist (avoiding the severe effects of dehydration, but making a great medium for bacteria to grow).
"Honey is also better than man-made antibiotics, Dr. Molan contends, because such antibiotics actually slow down the rate of cell growth. The moisture-attracting nature of honey, on the other hand, pulls body fluids and nutrients to the wound surface where they help speed skin growth and healing."
"All honey gives off hydrogen peroxide, a known antibiotic. The hydrogen peroxide is produced when the glucose in honey reacts with oxygen. The problem with peroxide as an antibiotic is that in large concentrations it breaks down in the presence of a common enzyme, producing the characteristic fizz we see when we put it on a cut. Because it is produced slowly in honey, at a low level, the peroxide doesn't loose its effectiveness. Provided honey is kept away from light, the enzyme which breaks down the hydrogen peroxide won't even activate."
Dr. Molan has now discovered a second antibacterial property, present in some but not all New Zealand honey. It has been shown to be effective against Helicobacter pylori, which is thought to be the major cause of stomach ulcers. Tests will begin soon in which patients will be given a tablespoon of this honey five times a day. This substance also works against highly resistant bacteria such as the MSRA bacterium which is gaining a reputation for closing down hospital wards.
DON'T LIMIT CALCIUM WHILE TRYING TO PREVENT KIDNEY STONES. (Adapted from Science News, Vol 143, March 27, 1993.) Most kidney stones are made up of crystals of calcium and a naturally- occurring substance in some plants called oxalates. Many plants contain such high amounts of oxalates that we must temper our enthusiasm for those plants. Amaranth leaves and carambola fruit are good examples.
The conventional wisdom is that people with kidney stones should cut back on calcium in their diet. According to a study reported in the New England Journal of Medicine, men who ate a diet rich in calcium had a 34% lower risk of kidney stones than men who followed a restricted calcium diet.
"This goes against everything we have been taught," said one of the authors, kidney specialist Gary Curhan. He suggests that the reason may be that oxalates in the diet combine with calcium in the intestine in normal diets, creating insoluble crystals that are excreted. A low calcium diet would allow more oxalate to enter the bloodstream and eventually form insoluble crystals with calcium in the kidneys.
Dr. Curhan is not recommending added calcium, but that calcium not be reduced. I cannot help but wonder, though, whether taking extra calcium when I am going to be eating high oxalate foods might result in more of the oxalates being excreted harmlessly.
On a side note, the same study also found that men who ate a potassium-rich diet had a 50% lower risk of stones than those who ate the least amount of potassium. Bananas, oranges and grapefruit are good sources of potassium.
HERBALGRAM is the journal of the American Botanical Council and the Herb Research Foundation. For those interested in botany and pharmacology, this will make a fascinating read. Articles often discuss toxicities and traditional medicinal uses of various plants, with a chemical-scientific focus. We often find an interesting but otherwise obscure abstract about a new use for one of the tropical plants we have on ECHO's farm. The book list is unbelievable; we often wish we had the budget to buy everything on the page! Subscriptions are $25/year, $60/3 years; foreign subscriptions add $10/year. Write the American Botanical Council, P.O. Box 201660, Austin, TX 78720, USA; phone 512/331-8868; fax 512/331-1924.
CAB INTERNATIONAL (CABI) HEALTH AND DISEASE PUBLICATIONS provide up-to-date medical information on a wide variety of topics. (CABI also works with agriculture, forestry, and natural resource management in developing countries.) The latest catalog mentions a new health and disease database which covers parasitology, tropical diseases, communicable diseases, human nutrition, public health, and medicinal and poisonous plants. The catalog lists newsletters, journals, books, and computer resources. Items listed are expensive, but this is a good resource for those needing specific medical information on a variety of health problems in tropical countries. Request information from CAB International, Wallingford, Oxon OX10 8DE, UK; phone (01491)832111; fax (01491)883508; e-mail firstname.lastname@example.org; http://www.cabi.org/.
Like many universities, ECHO has an "unofficial" phytosanitary certificate in which we certify that, to the best of our knowledge, seed came from disease-free and insect-free plants and that the seeds have been treated with insecticide and fungicide. If requested, we enclose this with seed orders large enough to require a package. If you believe this certificate would be helpful you can request that we enclose it. However, it will not be enough with higher-risk imports, such as cuttings or roots of sweet potatoes, and certainly will not suffice if your import permit requires an official phytosanitary certificate.
WHEN YOU SEND SEED TO ECHO. Our seedbank has been greatly enriched by seeds sent by overseas members of ECHO's network. If you have seeds to share, write first telling why you think we might be interested and giving as much information as you can. If it is a seed that we could use, we will send a green and yellow mailing label (a plant import permit) issued in our name by the Department of Agriculture. All you need to do then is put the seeds in a package, identify each packet, and use the permit as your mailing label. The seeds will be forwarded to us after inspection.
When you send seed to ECHO, please treat it with a modest amount of insecticide. Please do not cover the seeds in quantities of powders; our customs inspectors do not appreciate that, and they may dispose of overtreated seed. We do need to be careful about pests. Years ago, there were two containers of seed sitting on my desk, each with a different type of adult insect pest crawling all over them, both sent to us from overseas. Fortunately the containers were well sealed and I was able to destroy the pests promptly. In another instance I was not so fortunate. I had a bouquet of a dozen dried sorghum heads in a vase, each a different type from Purdue University's International Sorghum Variety Trial, which I had cherished for twelve years. Someone sent an envelope of corn from overseas, and it was left in my office for a few weeks. One day I noticed that small insects had emerged from the seeds inside the envelope. I immediately put the envelope in the freezer to kill the insects, and I disposed of the grain. A few weeks later, however, the same insect was discovered destroying my sorghum bouquet; by that time, it was too late to save the bouquet, and it had to be discarded as well.
A related issue: please do not send infested seed or a diseased leaf or soil in an envelope for us to identify. ECHO does not have an entomologist on staff, and we cannot have your problem getting loose at ECHO! If it is important to know what the insect is and you cannot find someone in country to identify it, you might be able to send it in alcohol. Be sure it is in a very sturdy and tightly sealed container. However, a description might be sufficient. In most cases, precise identification is not important. Given the lack of resources available in most peasant farming situations, it is usually enough, for example, to know that it is some kind of caterpillar or some kind of grain weevil. The low-technology options for control that are available are probably generic caterpillar controls or generic weevil controls anyway.
GETTING YOUR OWN SEED IMPORT PERMIT. It is easy for U.S. citizens to obtain their own permit. Permits are designed for mailing seeds to the States, but usually help get you through customs with modest amounts of permitted seeds that you are carrying with you. Some plants are not allowed entry, especially those listed as "noxious weeds." It might also be more difficult (and dangerous) to bring seeds of crops of major economic importance in the States. The inspector probably would not let you bring citrus or corn because of the economic damage that could be done by introduction of a new disease or pest. Permits can be easily obtained by any citizen by writing to Permit Unit, USDA, APHIS, PPQ, 4700 River Rd., Unit 136, Riverdale, MD 20737, USA; phone 301/734-8645; fax 301/734-5786. The USDA must first send you a formal application, so allow plenty of time for two exchanges by mail. Permits are good only for the particular port of entry that you specify (so ECHO's Miami permit cannot be used in New York). For living plants, you also need a post-entry quarantine permit and a place (it could be a residence) where the plant will be kept and federally inspected for two years.