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Surprising uses of ‘toxicants’ in ancient China

LIU ZHAO | 2022-03-03 | Hits:
Chinese Social Sciences Today

Mang-cao (Illicium lanceolatum) Photo: CFP

The meaning of the term “toxic” has varied with time. Different from what may result in death or severe physical harm in a modern sense, the original term “du-wu” or “toxicants” in Traditional Chinese Medicine (TCM) is considered a general “medicine” or strong “medicine.” In early documents, the term “du,” or “toxic,” refers to the powerful medicinal properties of medicine. 

The classification of herbal medicine according to the severity of medicinal properties has been described in Chinese materia medica. The Huangdi Neijing [Yellow Emperor’s Canon of Medicine, China’s earliest extant medical canon] classifies medicinal substances into the ones with great, moderate, mild, and no toxicity—[“To use drugs with great toxicity to treat a disease, the rule is to stop using it when 60% of the disease is cured; To use drugs with moderate toxicity to treat a disease, the rule is to stop using it when 70% of the disease is cured; To use drugs with mild toxicity to treat a disease, the rule is to stop using it when 80% of the disease is cured; To use drugs with no toxicity to treat a disease, the rule is to stop using it when 90% of the disease is cured” (trans. Li Zhaoguo)]. The Shennong Bencao Jing [Divine Farmer’s Classic of Materia Medica, an ancient text on medicinal plants] described medicinal substances as “upper,” “middle,” or “low.” The upper is believed harmless to humans, while the middle is potentially toxic. The low features a strong or violent effect on physiological functions. 
From ancient times to the present, medicine has been closely related to toxicants in TCM, especially in the treatment of severe cases, where toxicants were often used. Such ideas can be found in Shangshu [Book of Documents, a classic of Chinese political philosophy]—“[Be you] like medicine, which must distress the patient, in order to cure his sickness” (trans. James Legge). With various materials, processing techniques, measurements, and proportions, TCM skillfully applies toxicants in treatment, which often works miracles. Of course, the accurate proportion and measurement of toxicants is the key to success. The toxicants are a cure if used properly. Misuse of toxicants may lead to severe damage or even death. 
Wu-tou (aconitum carmichaelii), commonly known as Chinese aconite, is referred to as low herbs in the Divine Farmer’s Classic of Materia Medica. Wu-tou has been used as an essential medicinal herb in TCM mainly for the treatment of rheumatic disorder, hemiplegia, etc. The toxic ingredient of wu-tou is aconitine, the scientific name of which is diterpenoid alkaloid. Consuming as little as 0.2 milligrams of pure aconitine may cause poisoning, and 3-5 milligrams may cause death. The consumption of wu-tou can cause myocardial paralysis, and damage the function of peripheral nerves around the heart, with signs such as numbness in the tongue, lips, face, and limbs. This is followed by salivation, vomiting, irritability, palpitation, slow heart rate or tachycardia, blood pressure dropping, muscle rigidity, and respiratory spasm until death from suffocation. There are still people in south China who practice the tradition of making liquor from wu-tou, so poisoning by wu-tou often occurs.
In the manuscripts concerning health care unearthed from the Mawangdui Han Dynasty Tombs, wu-tou was also recorded as being used to help people live longer. It has been proven by modern medical tests that aconitine has the effects of acting as a stimulant for the heart and dilating blood vessels, which will increase the contraction of the myocardium, and make people feel uplifted. Hence, there is reason to use wu-tou as a longevity medicine.
Criminal use of wu-tou is also documented in ancient archives. Er Tan, a Ming Dynasty collection of short stories, recorded a case of trafficking humans by using drugs that were made of dozens of herbs, including wu-tou, and others. Because wu-tou is highly toxic and can easily be used for wrongdoing, dynasties often restricted the sale and use of wu-tou with legislation. Bamboo texts unearthed from Mount Zhangjia [in Hubei Province] recorded that any one who possessed or produced wu-tou toxicant without permission will be sentenced to qi-shi [execution of an offender sentenced to death at a market place].
The most prolific use of wu-tou in ancient China was in the military. Military use of wu-tou included poisoning enemies and applying poison to arrows and swords. An example of using wu-tou to poison enemies can be found in the Mozi [an ancient text attributed to the Chinese philosopher Mozi more than 2,000 years ago]: people living in border areas were often ordered to plant and store toxic herbs in advance such as yuan-hua (thymelaeaceae), mang-cao (illicium lanceolatum), and wu-tou; [to prevent the enemy from attacking the city] the wells outside the city could be landfilled, and the aforementioned toxic herbs would be placed in the wells which couldn’t be landfilled.
There are many records of making poisonous arrows with wu-tou. In the historical novel Romance of the Three Kingdoms, the renowned physician Hua Tuo heals General Guan Yu, who is hit by a poisoned arrow in the arm during the Battle of Fancheng in 219. Hua tells Guan that the arrow that injured him had wu-tou toxicant applied, which penetrated straight into his bones, and he would lose his arm if not properly treated in time.  
As an important military material, the possession or sale of wu-tou was prohibited, but official stockpiling was required. A bamboo text unearthed from Mount Zhangjia recounts that army and border administrations were allowed to produce wu-tou toxicant, but arrows with wu-tou toxicant should be stored carefully. Use of these arrows was permitted in hunting down invaders or thieves, but the arrows needed to be brought back and stored afterwards. Those who didn’t return the poisonous arrows and hid them for more than five days would be punished by law.
Illicium lanceolatum is a medicinal plant with the Chinese name ‘mang-cao.’ It is described as a low herb in the Divine Farmer’s Classic of Materia Medica. The branches, leaves, roots, and fruit of mang-cao are poisonous, with the shells of its fruit the most poisonous. Mang-cao is commonly used to treat traumatic injury, lumbar strain, arthritis, rheumatism, etc. Symptoms of being poisoned by mang-cao may include dizziness and nausea. In severe cases, it may lead to convulsions, difficulty breathing, and even death. Because the fruit of mang-cao look like star anise, there are still cases of being poisoned by mistakenly using mang-cao fruits as star anise.
In addition to being used as medicine, mang-cao can also be used to poison rats and fish. The specific method of poisoning fish by mang-cao recorded in the Bencao Gangmu [Compendium of Materia Medica, an encyclopedic TCM work written in the 16th century] is to mix mashed mang-cao with foxtail millet flour that has been stored for an extended period of time, then throw the mixture into the water. Fish that eat the mixture will be poisoned and then surface. People can eat these fish without any problems. 
Poisoning fish is similar to the practice of draining off the water to catch fish [an unsustainable way to fish], which not only contaminates the environment, but also harms other aquatic plants and animals. Therefore, many dynasties restricted the practice of poisoning fish by legislation. According to Xunzi [a collection of philosophical writings attributed to and named after Confucian philosopher Xunzi, more than 2,000 years ago], “If it is the season when the grasses and trees are in the splendor of their flowering and sprouting new leaves, axes and halberds are not permitted in the mountain forest so as not to end their lives prematurely or to interrupt their maturation. If it is the season when the giant sea turtles, water lizards, fish, freshwater turtles, loach, and eels are deposing their eggs, nets and poisons are not permitted in the marshes so as not to prematurely end their lives or to interrupt their maturation” (trans. John Knoblock). This record corresponds exactly to the laws of the Qin (221–207 BCE) and Han (206 BCE–220 CE) dynasties found in unearthed documents. 
Poisoning fish is regarded as “bad karma” in Buddhism. In Sheyi Zhi, a Ming Dynasty (1368–1644) compilation of short stories concerning supernatural phenomena, a story tells of a eunuch named Zhou Juecheng being killed during the Xuande Era (1426–1435) because he poisoned fish. This story is a reflection of this concept.
Yu-shi is also called du-sha, or arsenopyrite, an iron arsenic sulfide. It is the main raw material for producing pi-shuang [arsenic trioxide, one of the most famous poisons in ancient China]. Yu-shi is classed as low in the Divine Farmer’s Classic of Materia Medica. It is often used in the treatment of deep, painful boils in skin, hemorrhoids, anal fistulas, beriberi, etc. Since yu-shi is white, it is also called bai-shi [“white stone”]. It is known as one of the “five-color stones” together with red dan-sha (cinnabar), yellow xiong-huang (realgar), blue zeng-qing (copper sulfate), and black ci-shi (magnetite). The “five-color stones” were the main raw material of producing wushi-san (“five-stone powder”) and was widely used in ancient Chinese alchemy [an ancient Chinese approach to alchemy as a part of the Taoist body-spirit cultivation]. Between the 3rd and the 10th centuries, Chinese people believed that taking the five-stone powder could boost energy levels and reduce fatigue, or even achieve immortality. 
There are many ancient historical facts, cultures, and ideas behind those records of toxicants, which enable readers to have a clearer understanding of the various aspects of the ancient world. 
Liu Zhao is a professor from the Center for Research on Chinese Excavated Classics and Paleography at Fudan University.