We know that green plants utilize solar energy in various ways to produce chemical compounds necessary for their survival. These include chlorophyll, which allows plants to convert sunlight energy into food through a process called photosynthesis. However, did you know that some plants take this a step further and utilize solar energy directly in the synthesis of complex molecules required for their survival? In this article, we will discuss plant toxins, which are highly poisonous substances produced by certain plants that are harmful to humans as well as other animals. Some examples of these toxins are ricin, a lethal plant toxin that is found in the castor bean, and curcumin, which is a pigment and anti-inflammatory agent that is found in turmeric, and utilized by plants in the synthesis of lignin, the plant cell wall material. In addition to these toxins mentioned above, we will also examine pesticides, which are chemicals that are used to kill insects on or around plants. While many people are aware of the dangers of consuming pesticides, they may not know that some plants utilize pesticides in their defense against insects and other pests. We will examine the various ways that pesticides are found in plants, as well as the dangers that they pose to humans and the environment.
Plant Toxins
Just like animals, plants can be toxic to each other. Some examples of these toxins include but are not limited to:
- curcumins
- capsaicins
- chaconins
- ergot alkaloids
- aristolochic acids
- lindane
- benzyl isothiocyanate (found in gluetongs)
- chlordecones (found in strawberries)
- nicotinoids (found in soybeans)
- aristolochic acid (found in wolfberries)
- nicotianiods (found in wallnuts)
- hordenine
- harmine
- harmalines
- strychine
- ephedrines
- bufotenine
These toxins are extremely poisonous and can cause death in humans and other animals who consume them. However, plants use these compounds for their own defense, and so they are totally harmless to humans (unless you happen to be a bug!). Some examples of these toxins are shown below:
Ricin
Somebody asked me the other day what is the most poisonous substance known to man. Without hesitation, I replied, ricin. What is ricin? It’s pure poison. You don’t want to mess around with that stuff. It’s one of the most toxic substances known to man. If the seed falls on the ground and is not removed immediately, it can cause death. But it’s found in plants, so it doesn’t pose any threat to humans. However, ricin was once used to castrate rabbits. These castrations were done with a needle that was dipped in ricin. This is the kind of stuff that makes vets sick. It’s extremely toxic. Fortunately, while the body can’t reproduce, the brain is very smart, and so each new generation isn’t at risk of becoming deficient. That’s why doctors are able to treat diseases and ailments in subsequent generations; because the damage has already been done.
Capsaicins
Another extremely dangerous substance that is found in peppers is capsaicins. So what is capsaicins? It’s a compound that occurs naturally in peppers and other plants in the genus Capsicum. There’s a reason why this stuff is known as capsaicins. It has a very irritating effect on the human nerve endings. In fact, it can be harmful to human skin in large quantities. It’s been known to cause hives and other skin rashes in some people. Thankfully, there are only a few cases where humans were actually harmed by capsaicins. For the most part, it’s simply a problem of acute contact with skin. The worst that happens is that the skin can become irritated and red. Otherwise, it’s mostly harmless. Just make sure that you don’t ingest any, because it can cause vomiting and other gastrointestinal problems if you do. Like ricin, capsaicins were also used historically to castrate animals. However, while the effects of ricin are almost overnight, the effects of capsaicins can take much longer to appear. In some cases, it can even be days or weeks before the effects of capsaicins are visible. Once again, while capsaicins are very harmful to animals, they are harmless to humans. This is because humans have developed immunity to the effects of capsaicins over time. This is why you’ll rarely find cases of humans being harmed by capsaicins.
Chaconins
Chaconins are a group of alkaloids that are found in the seeds of the chacora fruit, also known as the tree fruit or the prickly pear cactus. This is a plant that is native to South America. The fruits of chacora trees are known for their large thorny stems. These are responsible for many of the cases of plant-induced skin rashes that we see in people. This is because the thorny stems are extremely irritating to the skin. It’s even been known for people to develop a severe case of psoriasis after being scratched by these poisonous plants. While not completely harmless, chaconins are significantly less toxic than most other plant toxins. They are also among the fewest known toxins to affect humans. For this reason, chaconins are frequently used as experimental drugs in clinical trials for psoriasis. Other uses for chaconins include, but are not limited to:
- insecticides
- fertility boosters
- anticarcinogens
- anti-inflammatory agents
- central nervous system stimulants
- vasodilators
- anti-hypertensives
- anti-Parkinson’s agents
- anti-psychotics
- molecular binders
- radioprotectants
- antioxidants
Like most toxic chemicals, chaconins can be poisonous to other animals. They have been known to cause paralysis, convulsions, and death in small animals, such as mice and rats. Even the tiniest animals can be harmed by chaconins. It is not uncommon for mice to make frequent excursions to the bathroom, as their bladder is very susceptible to the effects of chaconins. While the effects of chaconins in people are generally far less severe, it’s enough to cause skin rashes and other signs of irritation. Ingesting large quantities can cause gastrointestinal problems, as well. The prickly pear is also known to interfere with the function of the heart, so too much of this stuff can cause heart problems. This is why it’s extremely important to stay away from these plants if you have heart disease or are at risk of heart disease.