An Experimental Investigation concerning the Effects of "Tuba" (Derris elliptica) Fish-Poison.
By J. Argyll Campbell.
"Tuba" is a term used by the Malays to denote various plants which possess fish-poisoning properties. Derris elliptica Benth., Leguminosa, is the most powerful of these plants.
Interesting accounts of "tuba" fishing are given by George Maxwell (1) and W. H. Furness (2). According to these authors the root of the low climbing plant, Derris elliptica, is most commonly employed. The root is pounded by a club and then extracted by soaking it in water contained in boats. The soaked root is compressed and a milky-white watery fluid escapes. This fluid is mixed with lime to make it sink and spread when poured into the river. Previously a barricade has been erected some distance down the river to prevent the fish escaping. The poison stupefies the fish and they flee before it. Men in boats and on the barricade scoop up the fish in nets or spear them as they come to the surface. Furness says that the fish seem to be affected by suffocation.
Research has been done concerning the chemical composition of this poison. M. Greshoff (3) obtained a resin which he called "derrid" and which he found to resemble pachyrrhizid, timboine, niruoline and piscidine in composition. Wray (4) also isolated a resinous substance which he named "tubaine."
I can find no research concerning the actions of the poison upon the living tissues, although much has been written about its apparent actions. Greshoff (5) says that drinking the poison produces vomiting, dizziness and death. He records a case of suicide in Java. Ridley (6) mentions that "tuba" poison is speedily fatal to man when swallowed or to fish when in contact with the gills; and that it is used by Malays as an abortifacient (7). Gimlette (8) gives a good deal of information. Fish stupefied by the poison can be eaten with impunity by man. Chinese use the poison extensively as an insecticide, especially for spraying pepper vines. It is put into wells with criminal intent, but death seems to be rare. A decoction is used by Malay girls to produce abortion; death sometimes occurs owing to uterine haemorrhage. Acute cases of poisoning are characterised by fixation of the jaws. In Borneo the Dyak girls use it to commit suicide. It is also mixed with "ipoh" poison by the Sakei in preparation of dart poison for blow pipes.
