The "deadly killer" in the plant world may be right next to you! Let's take a look at the scientific investigation~

There is always a natural trust between humans and plants. In today's world of chemicals, plant essences, plant nutrition, wild vegetables and flower dishes... are favored by many people and have become synonymous with safety and health. Recently, the news that "a woman was poisoned and sent to the hospital after taking a photo with oleander in her mouth" became a hot search, suddenly reminding us: there are "deadly killers" among plants, and they are planted around us in large quantities! What are their types? How dangerous are they? Next, let's scientifically check the highly toxic plants around us.

1. Heart killer: Cardiac glycosides poisonous plants

Deadly: ★★★★

Concealment: ★★★★

Common plants: oleander, dieffenbachia, lily of the valley

These plants all contain a heart drug that has been used by humans for more than 200 years: cardiac glycosides. Once ingested, they first irritate the gastrointestinal tract and then directly attack the heart, causing arrhythmia at the mildest and life-threatening at the worst. Their toxicity is usually strong - taking 3 grams of dried oleander leaves at a time can lead to death.

Oleander (Photo by Wang Xi)

Cardiac glycosides were first extracted from Digitalis purpurea, commonly known as digitalis. Currently, this plant is widely used in greening. In modern China, digitalis was rare, and oleander was once planted in large quantities to extract cardiac glycosides. Among the poisonous plants of cardiac glycosides, there are many groups with "high appearance", such as the yellow cicada (Allamanda schottii) that looks like a golden wind chime, the fresh and refined lily of the valley (Convallaria majalis), milkweed (Asclepias curassavica), the side marigold (Adonis amurensis) known as the elf of the valley, and the large family of foliage plants "Dieffenbachia" with thousands of varieties, etc.

Foxglove

Lily of the Valley (Photo by Xue Kai)

Although not all cardiac glycoside plants are so strong, try not to let their juice come into contact with your skin, and don't make medicine or eat them on your own.

2. Nerve Agents: Alkaloid Toxic Plants

Deadly: ★★★★★

Concealment: ★★★★

Common plants: Aconitum, Datura, Veratrum

This type of plant is full of killers and can be regarded as the most dangerous and poisonous plant.

Beijing Evening News reported that on April 19, 2003, nine tourists entered Yunmengshan National Forest Park and dined at Guiguzi Village halfway up the mountain. After eating a plate of wild vegetables called "agar", they were poisoned and lost consciousness one after another. Two chefs in the kitchen were also poisoned and fell into a coma. After 120 emergency rescue, 10 people escaped, but 1 person unfortunately died - the culprit of this tragedy was a common plant in Beijing's mountainous areas: Aconitum carmichaelii.

Aconitum

The toxic component of Aconitum is an alkaloid: aconitine. It can paralyze the central nervous system and respiratory nerves, causing central nervous system depression and respiratory paralysis, leading to death. Medical research has shown that 0.2 mg of Aconitum can cause poisoning in ordinary people, and 3-4 mg can cause death. Therefore, a few Aconitum leaves mixed in wild vegetables, or a few Aconitum roots soaked in white wine, can easily kill people.

In addition, in Beijing's community gardens, a beautiful herb often suddenly appears: its branches are up to 1 meter high, its green leaves are lush and green, and its large golden flowers are like huge wind chimes. This is a highly poisonous plant that is as poisonous as Aconitum: Datura stramonium. It contains three powerful neurotoxins: hyoscyamine, atropine, and scopolamine. The ancients used it to make "sweating drugs", which made countless heroes bow down.

Mandala (Photo by Xue Kai)

Among the highly poisonous alkaloid plants, there are two "legendary poisons" that are rare in the north but must be mentioned: one is the famous "heart-breaking grass": Gelsemium elegans. It is a vine plant of the Loganaceae family, and a trace amount of ingestion can kill people. The flowers of Gelsemium elegans are similar to honeysuckle, and people often mistakenly use it to make tea and die; the other is the "pulling drug" that has killed countless people: Strychnos nux vomica. Its toxicity is cruel and fierce, stimulating the central nervous system of the human body. The face of the poisoned person is distorted with pain, and the body "pull forward dozens of times, with the head and feet together, like a pulling machine." It is said that Li Yu, the last emperor of the Southern Tang Dynasty, was poisoned to death by it.

3. Destroying the liver and kidneys: Toxic protein-based plants

Deadly: ★★★★★

Concealment: ★★★

Common plants: castor, Xanthium sibiricum, Abrus preparata

This kind of plant always makes people "love and hate". On the one hand, its seeds contain toxic proteins that can damage human liver and kidney cells, cause systemic bleeding, and eventually die from liver coma, respiratory and circulatory failure; on the other hand, they are important economic plants and cultural plants. For example, castor (Ricinus communis), which is common in the wild in Beijing, is a treasure and once ignited the hope of revitalizing industry for the Chinese. However, children can be poisoned and die if they accidentally eat 2-7 castor beans. Its toxicity is hundreds of times that of arsenic. Western agents smeared ricin on steel needles and steel balls to assassinate many important people. In the "Convention on the Prohibition of Biological Weapons" signed internationally in 1972 and the "Convention on the Prohibition of Chemical Weapons" signed in 1997, ricin is listed as a biological weapon. Former US Presidents Trump and Obama have received assassination letters containing ricin, which is also an important biological and chemical strategic weapon.

Castor (Photo by Xue Kai)

Another example is Xanthium strumarium, which is common in mountainous areas. It is a good medicine for rhinitis used in ancient and modern times, and it is also a special medicine for ancient people to treat prickly heat, eczema and various skin diseases. However, the whole plant is highly toxic, and there are many cases of poisoning or even death after ingestion. There is also Abrus precatorius, whose seeds are often used for decoration. Its seeds contain abscissa toxin protein, which is similar to ricin and can cause liver and kidney cell necrosis. The difference is that the poisoning is like lingering acacia, and usually takes several hours to several days of incubation period to appear. In mild cases, abdominal cramps, nausea and vomiting, and in severe cases, hematuria and coma. Northerners can pick up abscissa under the trees when traveling in Lingnan. Remember not to eat it by mistake.

Xanthium sibiricum (Photo by Xue Kai)

4. Attack the whole body: poisonous plants of acids, alcohols, and cyanogenic glycosides

Deadly: ★★★

Concealment: ★★★

Common plants: Aristolochia, Aristolochia strychnifolia

Aristolochic acid is a highly toxic plant of the acid and alcohol class, represented by Aristolochic acid. Aristolochic acid is contained in Chinese herbal medicines of the Aristolochiaceae family, which can cause severe kidney disease. In 1983, due to the shortage of Chinese herbal medicine Akebia, many pharmaceutical companies replaced Akebia with Aristolochic acid, a plant of the Aristolochiaceae family. Akebia contains aristolochic acid, which caused many people to suffer from renal failure after taking "Longdan Xiegan Pills"; in 1993, Belgium found more than 100 cases of renal failure in women after taking weight-loss pills containing Aristolochic acid, and found that this type of kidney disease was related to the aristolochic acid in Aristolochic acid. Therefore, whether for food or medicine, you need to be cautious when encountering Aristolochic acid, Aristolochic acid, Aristolochic acid, Aristolochic acid, Aristolochic acid, Aristolochic acid, Aristolochic acid, Asarum, etc.

Cyanogenic plants are represented by bitter almonds, peach kernels, ginkgo, and cassava. After poisoning, they mainly cause tissue cell suffocation and hypoxia. Oral intake of 60 grams of bitter almonds can be fatal for adults, and eating 5-10 raw ginkgo nuts can also be fatal for children. However, every year when ginkgo trees fall to the ground, the stench is not from cyanogenic substances, but from the orange-yellow fleshy seed coat of ginkgo, which contains butyric acid and heptanoic acid. After breaking, it emits a stench like fat deterioration and rotting fruit.

Mosaic cassava

Saponin-containing plants, such as Arisaema, Gleditsia sinensis, Pulsatilla chinensis, Phytolacca americana, etc., are very common in the mountains and wastelands of Beijing. Their toxicity can cause hemolysis and nerve stimulation, which can cause nausea and vomiting in mild cases and can be life-threatening in severe cases. Poisoning incidents are mainly caused by mistakenly picking wild vegetables and superstitious herbal remedies.

Arisaema sutchuenensis

To avoid plant poisoning, remember: do not touch, pick, or eat wild plants at random. Plants contain various chemical components, and in order to resist damage from insects, bacteria, fungi, viruses, etc., they may cause adverse reactions in people. Therefore, understanding science, knowing plants, and eating in moderation are the primary principles to ensure safety and health.

Written by Chen Hongyan, Deputy Director of the Science Museum of the National Botanical Garden (North Garden)