The Swiss physician and alchemist Paracelsus famously said, “All substances are poisons; there is none which is not a poison. The right dose differentiates a poison,” and he’s right. Even water in too large a quantity will kill you. However, some things require such a small amount to cause death – sometimes just a drop falling on a fully gloved hand – that they’re in a class all on their own. From flowers to heavy metals, from man made gases to venom, here are 25 Deadliest Poisons Known To Mankind. NOTE: This list is not ranked.
Cyanide can be in the form of a colorless gas or a crystal, but either way, it's pretty deadly. It smells like bitter almonds, and exposure to cyanide can cause symptoms such as headache, nausea, rapid breathing and heart rate, and weakness in just minutes. If untreated, cyanide kills by basically depriving the body's cells of oxygen. And yes, it can be made from apple seeds, but don't worry if you eat a few. You'd need to eat about ten apple cores before there was enough cyanide in your system to have an effect. Please don't do that.
Hydrofluoric Acid is a poison used in the making of Teflon, among other things. When in liquid from, it can easily seep through the skin and into the bloodstream. It reacts with the calcium in the body and can even destroy the underlying bone. The scary part? At first contact it's completely painless, leaving more time and possibility for it to do its damage.
Arsenic is a naturally occurring crystalline metalloid and is possibly one of the most well known and common poisons used as a murder weapon in the late 19th century. However, its known use in such a capacity goes back to the mid 1700's. Arsenic poisoning can kill in a few hours to a few days. Symptoms are vomiting and diarrhea, which made it difficult to distinguish from dysentery or cholera 120 years ago.
Belladonna or Deadly Nightshade is a highly poisonous herb/flower with a very romanticized history. The poison comes from an alkaloid called atropine, and the entire plant is poisonous, with the root being the most deadly and the berries being the least. However, just two ingested berries is still enough to kill a child. Some people use Belladonna recreationally as a hallucination, and in Victorian times women often used a tincture of Belladonna to dilate their pupils and make them appear more wide and glassy eyed. Before death, Belladonna can also give you seizures, rapid pulse, and confusion. Don't play with Belladonna, kids.
Carbon monoxide is odorless, tasteless, colorless, and slightly less dense than air. Also it will poison and then kill you. Part of what makes Carbon monoxide so deadly is because it's difficult to detect; it's sometimes called the "silent killer." It inhibits your body's ability to carry oxygen where it's needed - like to cells. To keep them alive and stuff. Early carbon monoxide poisoning symptoms are similar to the flu, minus the fever - headaches, weakness/lethargy, sleeplessness, nausea, & confusion. Luckily, you can get a carbon monoxide detector at every hardware or home improvement store!
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