CHAPTER XXV IRRITANT POISONS—(Contd.) B — ORGANIC POISONS 1. VEGETABLE POISONS Vegetable purgatives, when given in large doses, act as irritant poisons, and their action is due to an active principle, acrid oil or resin residing in them. When applied externally to the skin, they produce inflammation, pustular eruptions or vesications, and unhealthy callous sores or ulcers, When taken internally, the symptoms of gastro-intestinal irritation are more marked, while the nervous and cerebral symptoms are mostly absent. Death generally results from exhaustion. The post-mortem appearances are the signs of irritation and inflamma- tion of the alimentary canal. RICINUS COMMUNIS (CASTOR-OIL PLANT, ARANDI) t> The castor-oil plant belongs to N.O. Euphorbiacese. Its seeds contain an active principle, ricin, a toxalbumin or phytotoxin, which is a powerful irritant poison. A toxalbumin resembles a bacterial toxin in its action, and causes agglutination of the red blood corpuscles with some degree of haemolysis and cell destruction. The oil expressed from the seeds is a pharmacopoeial preparation, known as Oleum ricini, which is a viscid, nearly colourless or pale yellow liquid with a slight odour and a bland, acrid, unpleasant taste, It is soluble in 3J parts of alcohol (90 per cent). It is largely used in medicine, the dose being 60 to 240 minims. The residue left after pressure of the oil is highly poisonous, as it contains ricin, and should not, therefore, be given to cattle in their fodder. Symptoms.—Burning pain in the throat; nausea; violent vomiting; thirst -7 vertigo; colicky pain in the abdomen; rapid, feeble pulse; cold, clammy skin; cramps; prostration; collapse and death. Diarrhoea with bloody stools may or may not be present. Consciousness is retained till the end in some cases, while stupor or coma is observed in other cases. Fatal Dose and Fatal Period.—The lethal dose of ricin for a man weighing 60 kilogrammes is calculated by Stillmark * to b£ 6 milligrammes, which is generally equal to ten castor-oil seeds, although a single seed2 has pro* duced alarming symptoms, and two seeds s have caused the death of a man, 26 years old, in six days. On the other hand, recovery has occurred after a handful of the seeds (probably twenty-five to thirty or more) ,4 Treatment—Evacuate by washing out the stomach, administer stimulants and hypodermic injections of morphine, and apply warmth externally, Post-mortem Appearances.—Congestion, softening and inflammation of the mucous membrane of the alimentary canal, with occasional erosions and submucous haemorrhages. Fragments of the seeds may be found in the stomach and intestines. The blood is usually seen in the serous cavities. Detection of the Seeds.—There are two varieties of the seeds, viz. a large red seed with brown blotches yielding 40 per cent of oil which is largely 1. Arbiet d. Pharmakol Inst Dorpat, Pt HI, p. 59; Dymmock, Pharmac* IndL, VoL ULL, p. ov^L 2. Gullan, Brit. Med. Jour., May 6, 1905, p. 988. . 3. Meldrum, Brit. Med. Jour., Feb. 10, 1900, p. 317. 4 L, T. R. H-utchinson, Ind. Med. Gaz., May 1900, p, 196.