THE FOLLOWING ARTICLE APPEARED IN THE

NOVEMBER 1998 ISSUE

THE POISON SLEUTHS

DEATH BY ARGEMONE MEXICANA

-Dr. Anil Aggrawal

"Good morning doctor. Oh, my God, what are you doing today? You have the dead body of a young man today. His whole body is swollen, especially his legs. What happened to him? Please tell me."

"Good morning Tarun. The name of this young man is Ghanshyam, and he was found dead in his hospital bed today morning. He is about 32 years old, and belongs to a low socio-economic status family. He was a champion of the cause of downtrodden, and was their leader for quite sometime now. For some days he had been complaining of marked swelling of the whole body especially of his legs. He had some gastrointestinal symptoms also such as vomiting and diarrhea, but the doctors were not very much worried about these symptoms. The main cause of worry was his swelling which could be an indication of some heart or kidney trouble. He had been admitted to the hospital and investigations were being carried out, but today morning he was found dead. Doctors were initially quite at ease giving his cause of death as kidney failure, but there was some organization of Jhuggi-Jhompri settlements, which raised the doubt that the death could have been as a result of deliberate poisoning by someone. Obviously they seem to have some political clout too. Just after a delegation met the local MLA with this doubt, an inquiry was ordered, and hence the police has brought his dead body to me. My job is to find out how he actually died."

"But why would a person want to kill Ghanshyam? He does not seem to have a fight with anyone, does he?"

"We do not know yet. I may remind you, that Ghanshyam was a leader of the downtrodden, and he may have had some enemies. It is not uncommon for leaders to have enemies who can go to any extent to have the leader removed from their way. It is possible that Ghanshyam had some enemies, who might have done away with him with some poison. Once his body is cremated, and then if someone raises a doubt that he had been poisoned, we would not be in a position to do anything about it. But right now, we have his body in our possession. So it is indeed very prudent to find out the right cause of death right now. Especially since this has now become such a hot political issue."

"So what are you going to do now?"

"I went through the hospital records, and found out what symptoms he was suffering from. I also had a detailed discussion with the doctors who were treating him. I already told you that he was having diarrhea, vomiting and marked swelling of his body, especially his legs. On inquiring from the doctors, I found out some other symptoms too. He had loss of appetite, and his liver was enlarged and tender. He complained of tingling sensations in the skin, and tenderness of the calf muscles. But what really interested me was that he was also having increased intraocular pressure.."

"Sorry to interrupt you doctor, but what is meant by intraocular pressure?"

"Tarun, the word intraocular is a Latin word meaning inside the eye. It is the pressure exerted by the fluid inside the eye. Normal intraocular pressure or tension is about 15 mm of Mercury, which simply means that normally the pressure inside the eye is so much as to support a column of about 15 mm of mercury. If you compare this figure with certain other commonly known figures, you would be better able to appreciate this pressure. The normal systolic blood pressure is about 120 mm of mercury, which means that the pressure generated by heart during contraction is roughly 8 times the pressure inside the eye. The normal atmospheric pressure at sea level is 760 mm of mercury, which means that it is about 50 times higher than that found inside the eye. In raised intraocular tension, the pressure rises more than 25 mm of mercury. Increase in intraocular tension is technically known as glaucoma. Rise in intraocular tension occurs in very few poisonings. Coupled with other symptoms, I at once made a certain guess about the possible poison that he might have ingested.."

"What is that poison? Please tell me doctor. I am getting curious."

"Tarun, it comes from a plant called Satyanashi in vernacular. Botanically it is known as Argemone mexicana."

"Oh, I have heard about Satyanashi. It is a common weed found in our country, isn’t it?"

"Yes, you are right Tarun. Its seeds are very much similar to that of dark variety of mustard seeds. I must tell you mustard (which is edible) has two varieties of seeds, a dark variety (Brassica nigra) and a light variety (Brassica compestris). The light variety is yellowish and quite distinctive. The seeds of Argemone mexicana give out a very poisonous oil, known as Argemone oil or katkar oil. This oil also looks very much similar to mustard oil. So katkar oil is very much used to adulterate mustard oil. It appears Ghanshyam got adulterated mustard oil from somewhere and consumed it. That is why he got these symptoms."

"Just one thing doctor before we go ahead. Could you tell me, why this plant is called Argemone mexicana?"

"Yeah sure Tarun. The name Argemone comes from the Greek argema, meaning "a cataract in the eye". Interestingly, the juice of this plant was once very popular in the treatment of cataract and hence the name. Of course, now it is known that it is not only useless for treating cataract, but can in fact be dangerous to the eye. The name mexicana, simply refers to its native place Mexico. I may tell you that this is originally an American herbaceous annual belonging to the family Papaveraceae, but has now become a pantropical weed throughout tropical and subtropical parts of the world. It has come to India through activities of man and occurs as a local weed in cold season, exclusively in low rainfall regions at elevation from sea level to 2,500 m. It grows wild all over the country in wastelands and along roadsides. It is called Sialkanta in Bengal and North India, Satyanashi in Gujrat and Bharamdandi or Pila-Dhatura in Maharashtra. It is known by several other names such as Ujarkanta and Phirangi Dhatura. It is a robust prickly herbaceous annual, 1-4 ft high, with spreading branches. The flowers are 1-3 inch across and are colored yellow. Seeds are blackish brown, round and netted, and as I told you earlier, resemble those of mustard (Brassica nigra). The extract of the whole plant (latex) contains two alkaloids Berberine and Protopine. Seeds yield 22-36% of a pale yellow, nauseous, bitter, non-edible oil, which as I told you earlier is known as katkar oil or simply Argemone oil. This oil is rich in two other alkaloids Sanguinarine and Dihydrosanguinarine, the former being more toxic than the latter. These latter two alkaloids are mainly responsible for the poisonous symptoms produced by ingestion of Argemone oil. It is said that if katkar oil is heated to 2400 C for 15 minutes, it loses its toxic properties. Other alkaloids of lesser importance are cheletrythrine and coptisine."

"Doctor, you told me that the seeds of the dark variety of mustard look very similar to those of Argemone mexicana. Is there some test, by which the two can be differentiated?"

"Oh yes. Certainly. The light variety of mustard seeds (Brassica compestris) can easily be differentiated from Argemone by simple visual inspection. The tricky part is to differentiate the dark variety of mustard seeds (Brassica nigra) with those of Argemone. This is done by placing the seeds in normal saline. Mustard seeds will sink, while Argemone seeds will float. If you have trouble remembering this fact, remember the mnemonic 'False will Float'. Remember Argemone seeds are 'false' seeds."

"Oh, that is truly marvelous. Is there a scientific way to detect adulterated mustard oil too?"

"Oh, yes, there certainly is. There are at least three interesting color tests to detect adulterated mustard oil. The first is the Nitric acid test. We take 5 ml of adulterated oil and mix it with an equal volume of Nitric acid. The test tube is shaken and then allowed to stand. After some time the acid layer turns yellow, orange or crimson, depending on the amount of argemone oil in the adulterated sample. This is a simple test but has the great drawback of lack of specificity. This means that there are a number of false positives. The second is Ferric Chloride test. In this test, we use three reagents, namely Hydrochloric acid, ethanol and of course ferric chloride. The test is carried out in three steps. In step 1, two ml of adulterated oil is mixed with an equal amount of Hydrochloric acid and heated in a water bath at 35 degrees Celsius for two minutes. After this 8 ml of ethanol is added and heating continued for one more minute (Step 2). Finally in the third step we add 2 ml of ferric chloride, and the mixture is heated for a further ten minutes. If an orange-red precipitate forms, it indicates adulteration with Argemone oil. Finally there is the Cupric acid test, where 5 ml. of adulterated oil in taken in a test tube. One ml. glacial acetic acid and 2 mg. of cupric acetate solution are added to it. Development of green colour confirms the presence of argemone oil in the sample. Besides these color tests, the adulterated oil can also be detected by Paper chromatography and Thin Layer Chromatography (TLC). These are slightly complicated techniques, but I will tell you the basics of these tests. In paper chromatography, the mixture (of mustard and argemone oils) is allowed to run on a paper which is much like a blotting paper. The speeds with which each oil travels on this paper is different, with the result that after some time the two oils separate. These oils can be made visible by adding suitable reagents. This is the basis of paper chromatography. TLC is also quite similar. Paper chromatography is a very sensitive technique and can detect down to 0.0001% adulteration with argemone oil."

"Doctor, you earlier told me that Katkar oil is used to adulterate mustard oil. So does this mean it is cheaper than mustard oil?"

"Yeah sure. But an additional factor often held responsible for adulteration is the maturation periods of the two plants, which is almost similar. Those defending intentional adulteration (mainly merchants and retailers of mustard oil) often point to the fact that the two plants often grow together and ripe at the same time, so during harvesting, there is an inadvertent mixing of the two seeds. But this argument appears fallacious for several reasons. Argemone grows mostly on fallow land and mustard has a canopy that does not let anything grow under it. Mustard ripens in March and Argemone in May. By May mustard has already been harvested, so adulteration can only be intentional."

"Oh, I see. Does this mean Katkar oil has no use at all? It is only misused for adulteration."

"No Tarun. Katkar oil has several legitimate uses. It is used medicinally in several countries in the treatment of dropsy (swelling of the body), jaundice and skin diseases. It is often given as an aperient (laxative). It is also used for lighting lamps, as it is very cheap. I might tell you that although the seeds of Argemone look very much like those of mustard seeds, there are some important differences between the two. If the seeds are placed between two fingers and rubbed, the Argemone seeds are found to have spiny edges. Mustard seeds do not have such spiny edges. Furthermore the seeds of mustard are heavier having a specific gravity of 1.3 as compared to 1.08 of Argemone. This helps in easy differentiation. The seeds of mustard will drown in saline water of appropriate specific gravity (say 1.2), while those of Argemone will keep on floating. Always remember the mnemonic I told you earlier - 'False will Float"

"Oh, that is certainly interesting. Could you tell me the name of the disease one suffers from, when he consumes Katkar oil?"

"Tarun, the name of the disease is epidemic dropsy. Dropsy means swelling of the body, and the name epidemic is self-explanatory. This disease usually occurs in epidemic form. The reason is that when adulterated oil comes in the market, several people consume it and fall ill at the same time. That is why the name epidemic dropsy is quite apt, although modern textbooks of medicine rarely use this term now. I told you that the chief symptom of Argemone oil poisoning is marked swelling over the legs. The cause of this swelling (technically known as edema or dropsy) is the increased porosity of the blood vessels, which is caused by Sanguinarine. Because of the increased porosity, water leaves the blood vessels and comes to lie in the tissues. This is mainly responsible for the swelling. Sometime so much water oozes out of the blood that it accumulates in the cavities around the heart and lungs. Look here at Ghanshyam’s body. I have dissected the body for you. Can you see the fluid accumulated around his lungs and heart?"

"Oh, sure doctor. There is lot of fluid around his lungs and heart. And of course his legs are very much swollen. It is becoming clear to me now that he died of Argemone oil poisoning. I was just curious to know how old this disease is."

"Tarun, the first case of poisoning in the country was reported in Bombay in 1877. In 1926, a doctor in Bengal discovered its link with consumption of cooking oil adulterated with Argemone oil. In 1935, the scourge killed 1,500 people in Bengal, and in 1966 an outbreak incapacitated hundreds of people in Bombay. In 1983, dropsy created havoc in Delhi, and again in 1998 during the months of August and September. During 1998 epidemic in Delhi, a total of 2552 cases were reported officially of which as many as 65 died. I may tell you, that although katkar oil is poisonous to animals, they do not show classical symptoms of epidemic dropsy. Experiments have shown that monkeys and cats develop sleepiness and diarrhea culminating in death. Guinea pigs and mice lost weight and died without showing any symptoms. Since epidemic dropsy can not be produced in animals, most studies on the Argemone oil have been done on human volunteers."

"Doctor, have the outbreaks of Argemone poisoning occurred in other countries too, or is it just a peculiarity of our country?"

"Tarun, Argemone poisoning has occurred in several other countries too, namely Fiji islands, South Africa and the 3 Ms - Madagascar, Myanmar and Mauritius. In our own country, it seems to occur more commonly in Northern India. South India has rarely suffered from this condition perhaps because mustard oil is not very popular there. Another interesting fact is that while almost all outbreaks of poisoning have occurred due to contamination with argemone oil, in South Africa an epidemic occurred due to adulteration of wheat flour with argemone seeds."

"Oh, I see. So how do we arrive at the final diagnosis that Ghanshyam indeed has died due to Argemone oil poisoning?"

"Tarun, I looked at his eyes, and dissected the retina. His intraocular tension is high. In addition, I also saw retinal hemorrhages, which is another thing that occurs in Argemone oil poisoning. Look here at the retina, which I have dissected out. Can you see retinal hemorrhages here?"

"Oh sure doctor, they are very obvious. What else?"

"Tarun, I told you that Sanguinarine causes dilation of blood vessels. Owing to dilation of peripheral blood vessels, a bluish mottling appears on the skin. Here you can see those bluish mottlings all over his skin. You can also see some small, fleshy, dark red, warty growths or nodules in the mucous membranes of cheek, gums, tongue and nose. This is quite characteristic of Argemone oil poisoning. Another characteristic thing is enlargement of liver. In this case too, it is enlarged. So we are almost sure that Ghanshyam died of Argemone oil poisoning. I have enquired the place from where Ghanshyam used to buy his mustard oil. It is from a local retailer Kauwa Ram. Come let us tell the police to seize all oil from his possession. It is quite obvious that he has adulterated the mustard oil with Argemone oil, and is selling it to gullible public for his own profit."

"Oh yeah, this was a most interesting discussion doctor. Because of your sterling sleuthing, this dishonest trader will be caught and the public will be saved of this unnecessary agony. Tell me what are you going to tell me the next time?"

"Tarun, next time, I would tell you about a very interesting poison- Sodium chlorate." "