Today I’m going to talk about: Poison I’ve divided my presentation into two parts: First I’d like to introduce the poison and second I’ll present of samekinds of poison. So, let’s start with introduce Poison, any substance that produces disease conditions, tissue injury,or otherwise interrupts natural life processes when in contact with orabsorbed into the body. Most poisons taken in sufficient quantity arelethal. A poisonous substance may originate as a mineral, vegetable, or ananimal, and it may assume the form of a solid, liquid, or gas. A poison,depending on the type, may attack the surface of the body or, moreseriously, internal organs or the central nervous system.

Finally let’s consider: with kinds of poison Poisons in humans are usually classified according to their effects ascorrosives, irritants, or narcotics; the last named are also known assystemic or nerve poisons. Corrosives include strong acids or alkalis that cause local tissuedestruction, externally or internally; that is, they “burn” the skin or thelining of the stomach. Common or so-called household corrosive poisonsinclude hydrochloric acid, carbolic acid, bichloride of mercury, andammonia. Irritants such as arsenic, mercury, iodine, and laxatives act directlyon the mucous membrane, causing gastrointestinal irritation or inflammationaccompanied by pain and vomiting; diluted corrosive poisons also have theseeffects. Irritants include cumulative poisons, those substances that can beabsorbed gradually without apparent harm until they suddenly take effect. Narcotic poisons act upon the central nervous system or upon importantorgans such as the heart, liver, lungs, or kidneys until they affect therespiratory and circulatory systems. These poisons can cause coma,convulsions, or delirium. Narcotic poisons include alcohol, opium and itsderivatives, belladonna, turpentine, potassium cyanide, chloroform, andstrychnine. Also included in this category is one of the most dangerous

poisons known, botulin toxin, a potent bacterial toxin that is the cause ofacute food poisoning (see Botulism). Blood poisoning, also bacterial in nature, is a condition that occurswhen virulent microorganisms invade the bloodstream through a wound or aninfection. Symptoms include chills, fever, prostration, and ofteninfections or secondary abscesses in various organs (see Septicemia). Mostpoison gases also affect the bloodstream. Because these gases restrict thebody’s ability to absorb oxygen, they are often considered in a separatecategory called asphyxiants, to which group ordinary carbon monoxidebelongs. Gas poisons, however, may also be corrosives or irritants