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Beware the Beauty - the Poisonous plants in your garden
Nassau is famous for its flowering plants and trees, many of which originate from the four corners of the earth. Beautiful as many of these plants are, a surprising number are highly poisonous. In my garden in Nassau I counted six plants that could cause severe poisoning if parts of the plant were eaten!

Strangely, many Bahamian poisonous plants belong to the same family as the Potato - that staple carbohydrate source of the British and American diets. In fact, the Potato itself can be poisonous if eaten when green or sprouting. The plants in the Potato family - the Solanaceae contain toxic alkaloids similar to the drug atropine, which has a number of pharmacological uses. Members of this family include the Black Nightshade, often known locally as the 'Pepper Bush', the Chalice Vine, the Day Jessamine, the Angel's Trumpet and its close relative the Devil's trumpet.
When I renovated my house in Nassau, I planted the Chalice Vine (Solandra nitida) around the pergola by the front door. We even called the house 'Solandra' after the plant! The Chalice Vine's striking trumpet shaped flowers perfectly complemented the colour of the house and provided the perfect tropical touch. However, I made sure that my young children understood that they were not to touch the flowers for they contain the powerful alkaloid solandrine - a toxin which has been responsible for several cases of near-fatal poisoning in Florida.
Rather similar is the Angel's Trumpet (Datura candida), its flowers however, hang vertically and taper to a narrow point at the stem. Children have been poisoned by sucking the nectar of these flowers or merely by placing the Datura flowers in their mouths and blowing through them as if through a trumpet. Symptoms of such poisoning include dilated pupils, dryness of the mouth, and difficulty in swallowing, hallucinations, uncoordination, and muscular and respiratory paralysis.
Another member of this family with rather small but fragrant flowers is the Day Jessamine (or  Day Jasmine), Cestrum diurnum. This is a rather untidy looking plant that is often found in gardens. Its flowers are followed by whitish berries that turn black as they ripen. The berries of the day Jessamine, if eaten, cause similar symptoms to those caused by the Angel's Trumpet, but the leaves are high in substances resembling the cardiac glycoside ouabain, which causes heart stimulation, and has been used to treat congestive heart failure.
The Black Nightshade, Solanum nigrum, is a common weed in Nassau gardens. It too contains poisonous alkaloids, and has resulted in many cases of poisoning. Known in the Bahamas as the 'Pepper Bush', it has been used with petroleum jelly to prepare a poultice for boils.
Several local plants contain powerful purgatives, and some have been used in bush medicine. A familiar tree downtown is the Sandbox, Hura crepitans. It grows in Parliament Street, George Street, and on Lover's Lane off Shirley Street. Easily distinguishable by its spiky grey bark, it produces a curved seed pod (see photo on left) that is used to fashion the 'toothed,' necklaces often peddled on Bay Street. These seeds contain a potent substance called ricin which causes violent vomiting and diarrhea, and sometimes convulsions and circulatory collapse. Allergic reactions have been produced by merely handling the seeds of the Sandbox tree! 

This same substance ricin is found in the seeds of the Castor oil bean Ricinus communis, a very common and widespread weed in Nassau, particularly on land that has been recently cleared, and then allowed to re-grow. Dr Julia Morton of the University of Miami, a noted specialist on tropical poisonous plants, has written that as few as two or three seeds have been known to kill children, while six can kill a horse.

The Ackee, Blighia sapida, is an African Tree, widely grown in Jamaica where its cooked fruit is known as 'vegetable brains.' Actually the only edible part is the fleshy aril surrounding the seed, and then only when it is completely ripe and the fruit has split, for until then it contains the poison hypoglycin, which causes vomiting, exhaustion, prostration, and possibly coma and death. 

Between 1886 and 1950, approximately 5,000 deaths in Jamaica were attributed to Ackee poisoning. The seeds of the Ackee also contain hypoglycin, and the red distinctive rind contains Saponin, used in Jamaica for poisoning fish.


 A more recent case in Africa is noted below from the Lancet -  Author/s: Honore A. Meda - Issue: Feb 13, 1999:

Background: On March 21, 1998, the Regional Health Authority of Bobo- Dioulasso, Burkina Faso, asked the Centre Muraz to investigate an unexplained outbreak of epidemic fatal encephalopathy (EFE). We aimed to identify the cause of this epidemic.

Methods: We identified cases retrospectively through review of health- service records and interviews of family members, village chiefs, and local healers. Active surveillance was started in administrative divisions within the study area in April, 1998, to identify further EFE cases. We did a case-control study of households to investigate the risk from various environmental and health factors. Blood and urine samples were collected if possible and urine dicarboxylic acid concentrations measured by gas chromatography.

Findings: 29 cases of EFE were identified from January to May, 1998. Estimated age-specific attack rates (2-6 years) ranged from 31 to 847 per 100000 population (p<0.001). The most common symptoms were hypotonia, vomiting, convulsions, and coma. All children died in 2-48 h. The only factor associated with EFE was the presence of ackee trees (Blighia sapida) within 100 m of households (odds ratio 5.1 [95% CI 1.8-14.7] p=0.001). Poisoning with unripe ackee fruits was suggested by urine concentrations of dicarboxylic acids four to 200 times higher in cases (n=2) than in controls (n=3).

Conclusion: Consumption of unripe ackee fruit probably caused this epidemic and may lead to a substantial number of unexplained deaths in preschool children in west Africa every year. Educational campaigns have the potential to prevent these deaths.

An important source of starch for Indians and early settlers in Florida - and presumably for the Indians of the Bahamas, was the rootstock of the Coontie, Zamia floridana and Z. pumilla. A strange and primitive fernlike plant, the Coontie is common in the pine barrens of New Providence (see my article 'The Coontie'). Only after peeling, grating, and repeatedly washing in water, can the root be used as a food. The water used in the washing process must be discarded as it contains the poison cycasin.

 

One of the Bahamas' more dangerous flowering plants is the familiar Oleander, Nerium oleander used extensively in the landscaping of Independence Drive, and near the entrance of the Seafloor Aquarium. All the parts of this attractive plant contain toxic glycosides similar in action to the drug digitalis. If eaten, this plant causes nausea, vomiting, cramps, lowered pulse, convulsions and possibly death. Even burning the plant produces a poisonous smoke, and bees gathering nectar from the flowers have even been known to make poisonous honey!


This article is not intended to frighten the reader from venturing into his garden, but it should serve as a warning to all parents, and those supervising children. Young hands have an invariable tendency to convey interesting objects to young mouths, and these objects may include pretty flowers and berries - deadly flowers and berries!.

 

Of the plants I have mentioned on this page, four were growing in my garden, two were in my neighbour's yards and two were prominent in public places in Nassau. We must always instruct our children not to touch and eat strange plants, or we may see some of the more unfortunate consequences of the meeting of Man and Nature

 

R. Attrill 2006