One of the most poisonous plants in the world: WATER HEMLOCK

Look out, because we are about to introduce you to one of the most poisonous, dangerous plants in existence. What is this plant you ask? Why it’s the Water Hemlock. It looks harmless enough, but don’t let its humble appearance trick you. It is a very dangerous and poisonous plant that has the potential to kill.

We rely on plants for a myriad of things. Plants make up the material we use to build our houses, manufacture our products and certain plants provide a vital food source for developing countries. Many plants have healing abilities embedded into them and are used as medicine to cure diseases naturally. They’re also common source feed for animals making them a key component in our food industry. So plants are pretty great, but there are certain plants out there that are known to do more harm than good.

INTRODUCING: The Water Hemlock

Also known as the “Cicuta”. This very poisonous plant belongs to a small genus of four species of dangerous plants. The Water Hemlock is a perennial herbaceous plant, meaning that it can live up to two years and has the ability to survive through the harshest of winters, growing back in full bloom in the spring. These plants can grow up to a height of 2.5 meters (or 8.2 ft.). They have green and white flowers that dangle down like an umbrella growing easily in temperate climates. They are most commonly found in North America and Europe and grow in wet fields, along stream banks and other swampy places. The stem of this plant is forking, straight, even and hollow with leaves diverging from the fork. At the base of its stem is a tuberous root with thickened rootstocks, meaning they have thickened roots in the underground part of the plant with rootstock.


So what makes the “Cicuta” one of the most dangerous plants out there? Well, the Water Hemlock rootstock is a multi-chambered root that contains an oily, yellow-colored substance that turns red when it is exposed to the air. Fun fact: it kind of smells like a carrot or parsnip. A property of the poisonous substance, the cicutoxin, is an allergic reaction. It has the capability to aggravate the skin because of their mucous membranes and their antibacterial activity. The cicutoxin has a chemical structure closely related to oenanthotoxin which is a poison that affects the central nervous system. This can spell disaster for those who have an unknown allergy to this plant. The cicutoxin is present in all growth stages and parts of the Water Hemlock, however; it is mostly concentrated in the roots and appears to be most toxic at the beginning of spring. The effect of the cicutoxin acts as a stimulant on the central nervous system. It is a non-competitive (GABA) which stands for “gamma-aminobutyric acid” and is the primary inhibitory neurotransmitter in the mammals’ central nervous system. Its principal role is reducing neuron excitability throughout the nervous system, so if ingested, it can be fatal.


You might be looking at the image of the Water Hemlock and swear that you’ve seen this flower randomly in your backyard. You might be right, but there’s also another flower that looks suspiciously similar to the water hemlock and that’s the “Queen Anne’s Lace”. This flower is not poisonous at all, in fact; I’m one hundred percent sure you made fake cigarettes out of their stems when you were a kid.

A good rule of thumb is to check out its leaves. A water hemlock will have more leaves on its stem than a queen anne’s lace which tends to have none at all.

Another difference is the stem. A Queen Anne’s Lace will have a hairy, almost fuzzy stem whereas a Water Hemlock will have a smooth, green stem with brown speckles. A Queen Anne’s Lace will also have a more uniform, compact look. It’ll look more like a snowflake or a single flower all packed together. A Water Hemlock will have little flowers in it that “stem out” in all directions.

Both are white, but the Water Hemlock will have a more purplish hue to it. Also…a Water Hemlock’s leaves are smooth, whereas a Queen Anne’s Lace leaves are hairy, like the stem. If you look at both of these plants side by side, the Queen Anne’s Lace looks more delicate and like a house flower whereas the Water Hemlock definitely looks more “wild” and “dangerous.


There are records dating back to 1670 which show people who have died from the consumption of one of the world’s most dangerous plants. The Water Hemlock is so dangerous that even the smallest drops of the cicutoxin can cause death, especially when it’s ingested in the springtime. There are reports of some children who died from it by simply making a blow whistle from the stem.

There was also a case reported by a family who rubbed the plant on their skin and was instantly poisoned, along with the two children who died as a result of the topical contact from the plant.

Another case took place in 1992 when a 23-year-old man and his 38-year-old brother were hunting for ginseng in Maine. The younger of the two gathered a multitude of different plants from that specific area and proceeded to take about three bites from the root of the plant he picked. His brother also took a bite from the plant. After about 30 minutes the 23-year-old started to vomit violently. They ran out of the woods and called 911 right away. The sick brother laid on the ground until the paramedics came. When they arrived on the scene they saw that the man was unresponsive, a symptom of being heavily poisoned. He also had dilated pupils, mild tachycardia and profuse salivation meaning he was drooling heavily at the mouth. The man then began to experience severe seizures. When he reached the emergency room, he was given charcoal tablets and got his stomach pumped.

Even though the brother wasn’t having any symptoms, he was still treated the same way. He ended up getting an onset of symptoms about 2 hours after ingesting the root. Unfortunately for the younger brother, he died just 4 hours after eating the root. Proving that this harmless-looking plant is a real killer.

Based on the mortality files of the CDC’s National Center for Health Statistics, between the years of 1979 and 1988…around 58 deaths due to the ingestion of water hemlock were recorded. Many died due to misknowledge on the plant itself, thinking it’s a fruit or vegetable growing out of the ground. It has a similar appearance to overgrown parsley so some people have yanked it out of their garden, thinking it’s a common parsley stalk, when it’s really one of the most dangerous plants around.

Other names for Water Hemlock are beaver poison, children’s bane, poison parsnip, death of man and false parsley. It falls under the same umbrella as celery, parsley, carrots and parsnips. Pick a Water Hemlock and you’ll see that it actually smells pretty good. It smells like a turnip and tastes sort of sweet, like a carrot. But don’t let the yummy taste fool you…this is a highly poisonous plant.

Humans will commonly fall victim to Water Hemlock poisoning, but it’s the animals who are usually the most at risk. Livestock such as cows, chickens, ducks, horses and goats have no idea which plants are poisonous and which plants aren’t, so this makes them especially vulnerable. The poisoning of a herd is a typical event that takes place when water hemlocks aren’t removed from pastures. When the soil is moist in spring, this is often the time when cows will unknowingly eat the most toxic part of the Water Hemlock plant, its roots. The death can take place in at least 15 minutes, if not less.

Dogs will most commonly get Water Hemlock Poisoning by licking water that’s been running through Water Hemlock patches. Since dogs are a lot smaller than humans, many don’t make it to the treatment phase and will pass away fairly quickly. It’s important though to keep in mind that not all Water Hemlocks are created equal. The more mature plants are actually lower in poison than the young ones so if your dog snatched one of the older flowers. It might not be a total lost cause.

A similar treatment is required for dogs who are experiencing Water Hemlock poisoning. They will be given activated charcoal and will get their stomach pumped, just like a human. It’s definitely fair to say that dogs and animals get poisoned for more often than humans due to their lack of common sense!


The two main symptoms associated with a Water Hemlock poisoning include generalized seizures which affect the cerebral hemispheres, and loss of consciousness (briefly or for a more extended period of time). The symptoms will appear in as little as 15 minutes after the consumption of the plant, sometimes faster in children. Before the generalized seizure takes place, the victim might experience some or all of the following: dizziness, confusion, abdominal pain, tremors or shaking, drowsiness, nausea, and weakness. Other symptoms may appear alongside the seizure including a decrease in pH blood level and metabolic acidosis (a condition that occurs when the body produces excessive quantities of acid or when the kidneys are not removing enough acid from the body.) Also, the person might experience upon consumption of the Water Hemlock, blood coagulation disorders, swelling in the brain, kidney failure and skeletal muscle breakdown.

Water Hemlock poisoning can also cause neurological symptoms which might consist of: tingling, hallucinations, coma, dilated pupils, and numbness of the skin. A person could also experience cardiovascular symptoms such as high blood pressure or low blood pressure, rapid heartbeat or slow heart rate. Death usually happens due to respiratory failure, which is a condition when there isn’t enough oxygen passing through your lungs into your blood. Your body’s organs, such as your heart and brain need oxygen-rich blood to function properly. Respiratory failure can also take place if your lungs are unable to efficiently remove carbon dioxide (a waste gas) from your blood. Excess volume of carbon dioxide level in the blood can harm your body’s organs. Both of these problems — a low oxygen level and a high carbon dioxide level in the blood can occur at the same time and according to, causes ventricular fibrillation which is a disordered electrical activity in the heart causing the heart’s lower chambers to quiver or fibrillate instead of contracting normally. This prohibits the heart from pumping blood, causing collapse and cardiac arrest. This is what happens in a few hours after Water Hemlock poisoning.

People who are lucky to receive treatment from experts in Water Hemlock poisoning usually recuperate within 24 to 48 hours. However, seizures may continue for up to 96 hours. Long-term effects can occur occasionally such as “retrograde amnesia,” which is a type of memory loss that makes the person forget whatever happened before consumption. Other milder effects may include restlessness, muscle weakness, jerking, and nervousness. Some of these symptoms may continue for days, even months.


So what type of therapy can a victim expect upon ingesting one of the most dangerous plants in existence? The victim might require gastrointestinal cleansing with activated charcoal which is used as an emergency treatment for Water Hemlock poisoning, preventing the poison from being absorbed from the stomach into the body. Sometimes even several doses of activated charcoal are needed to treat severe poisoning. This treatment is performed only if the patient has consumed the substance up to one hour before, and has a normal undamaged airway or is intubated (where they insert a breathing tube inside the patient’s mouth to help them inhale and exhale air). Unfortunately, there is no known antidote for Water Hemlock poisoning. Other treatments might consist of controlling the seizures with different medications, but they bring their own side effects. Let’s just say, it’s best to stay away from this poisonous plant.



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