Poison is a chemical substance that has a detrimental effect to life. The term is used in a wide range of scientific fields and industries, where it is often specifically defined. It may also be applied
colloquial
Colloquialism (), also called colloquial language, everyday language or general parlance, is the linguistic style used for casual (informal) communication. It is the most common functional style of speech, the idiom normally employed in convers ...
ly or figuratively, with a broad sense.
Whether something is considered a poison may change depending on the amount, the circumstances, and what living things are present. Poisoning could be accidental or deliberate, and if the cause can be identified there may be ways to neutralise the effects or minimise the
symptoms.
In
biology
Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditar ...
, a poison is a
chemical substance
A chemical substance is a form of matter having constant chemical composition and characteristic properties. Some references add that chemical substance cannot be separated into its constituent Chemical element, elements by physical separation m ...
causing death, injury or harm to
organism
In biology, an organism () is any life, living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy (biology), taxonomy into groups such as Multicellular o ...
s or their parts. In
medicine
Medicine is the science and Praxis (process), practice of caring for a patient, managing the diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, and Health promotion ...
, poisons are a kind of
toxin that are delivered passively, not actively. In industry the term may be negative, something to be removed to make a thing safe, or positive, an agent to limit unwanted
pests
PESTS was an anonymous American activist group formed in 1986 to critique racism, tokenism, and exclusion in the art world. PESTS produced newsletters, posters, and other print material highlighting examples of discrimination in gallery represent ...
. In
ecological terms, poisons introduced into the environment can later cause unwanted effects elsewhere, or in other parts of the
food chain.
Modern definitions
In broad metaphorical (colloquial) usage of the term, "poison" may refer to any thing deemed harmful.
In
biology
Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditar ...
, poisons are
substances that can cause
death
Death is the irreversible cessation of all biological functions that sustain an organism. For organisms with a brain, death can also be defined as the irreversible cessation of functioning of the whole brain, including brainstem, and brain ...
, injury or harm to
organs,
tissues,
cells, and
DNA usually by chemical reactions or other
activity on the
molecular scale, when an organism is exposed to a sufficient quantity.
Medicinal fields (particularly
veterinary medicine) and
zoology
Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the animal kingdom, including the structure, embryology, evolution, classification, habits, and ...
often distinguish poisons from ''
toxins'' and ''
venoms''.
Both poisons and venoms are toxins, which are
toxicants produced by organisms in nature.
The difference between venom and poison is the delivery method of the toxin.
Venoms are toxins that are actively delivered by being injected via a bite or sting through a ''venom apparatus'', such as
fangs or a
stinger, in a process called
envenomation,
whereas poisons are toxins that are passively delivered by being swallowed, inhaled, or absorbed through the skin.
Uses
Industry,
agriculture
Agriculture or farming is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled peop ...
, and other sectors employ many poisonous substances, usually for reasons other than their
toxicity
Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subs ...
to humans. For example, many poisons are important
feedstocks (e.g. feeding chickens Arsenic antihelminths
),
solvent
A solvent (s) (from the Latin '' solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for ...
s (e.g. rubbing alcohol, turpentine),
cleaners (e.g. bleach, ammonia),
coatings (e.g. Arsenic wallpaper
), and so on. Even the toxicity itself sometimes has economic value, when it serves agricultural purposes of
weed control and
pest control. Most poisonous industrial compounds have associated
material safety data sheets and are classified as
hazardous substances. Hazardous substances are subject to extensive regulation on production, procurement and use in overlapping domains of
occupational safety and health
Occupational safety and health (OSH), also commonly referred to as occupational health and safety (OHS), occupational health, or occupational safety, is a multidisciplinary field concerned with the safety, health, and welfare of people at ...
,
public health
Public health is "the science and art of preventing disease, prolonging life and promoting health through the organized efforts and informed choices of society, organizations, public and private, communities and individuals". Analyzing the det ...
,
drinking water quality standards,
air pollution
Air pollution is the contamination of air due to the presence of substances in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. There are many different type ...
and
environmental protection
Environmental protection is the practice of protecting the natural environment by individuals, organizations and governments. Its objectives are to conserve natural resources and the existing natural environment and, where possible, to repair da ...
. Due to the mechanics of
molecular diffusion, many poisonous compounds rapidly diffuse into
biological tissues
In biology, tissue is a biological organizational level between cells and a complete organ. A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function. Organs are ...
, air, water, or
soil
Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former ...
on a molecular scale. By the principle of
entropy
Entropy is a scientific concept, as well as a measurable physical property, that is most commonly associated with a state of disorder, randomness, or uncertainty. The term and the concept are used in diverse fields, from classical thermodyna ...
,
chemical contamination is typically costly or infeasible to reverse, unless specific
chelating agents or
micro-filtration processes are available. Chelating agents are often broader in scope than the acute target, and therefore their ingestion necessitates careful
medical
Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care practi ...
or
veterinarian supervision.
Pesticides are one group of substances whose toxicity to various insects and other animals deemed to be pests (e.g.,
rat
Rats are various medium-sized, long-tailed rodents. Species of rats are found throughout the order Rodentia, but stereotypical rats are found in the genus ''Rattus''. Other rat genera include ''Neotoma'' ( pack rats), ''Bandicota'' (bandicoot ...
s and
cockroach
Cockroaches (or roaches) are a Paraphyly, paraphyletic group of insects belonging to Blattodea, containing all members of the group except termites. About 30 cockroach species out of 4,600 are associated with human habitats. Some species are we ...
es) is their prime purpose. Natural pesticides have been used for this purpose for thousands of years (e.g. concentrated
table salt is toxic to many
slugs).
Bioaccumulation
Bioaccumulation is the gradual accumulation of substances, such as pesticides or other chemicals, in an organism. Bioaccumulation occurs when an organism absorbs a substance at a rate faster than that at which the substance is lost or eliminated ...
of chemically-prepared agricultural
insecticides is a matter of concern for the many species, especially
bird
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweig ...
s, which
consume insects as a primary food source. Selective toxicity, controlled application, and controlled
biodegradation are major challenges in
herbicide and pesticide development and in
chemical engineering generally, as all lifeforms on earth share an underlying
biochemistry
Biochemistry or biological chemistry is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology ...
; organisms exceptional in their environmental resilience are classified as
extremophile
An extremophile (from Latin ' meaning "extreme" and Greek ' () meaning "love") is an organism that is able to live (or in some cases thrive) in extreme environments, i.e. environments that make survival challenging such as due to extreme tempe ...
s, these for the most part exhibiting radically different susceptibilities.
Ecological lifetime
A poison which enters the
food chain—whether of industrial, agricultural, or
natural origin—might not be immediately toxic to the first organism that
ingests the toxin, but can become further concentrated in
predator
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill ...
y organisms further up the food chain, particularly
carnivore
A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other ...
s and
omnivores, especially concerning
fat soluble poisons which tend to become stored in biological tissue rather than excreted in
urine
Urine is a liquid by-product of metabolism in humans and in many other animals. Urine flows from the kidneys through the ureters to the urinary bladder. Urination results in urine being excreted from the body through the urethra.
Cellular ...
or other water-based
effluents.
Apart from food, many poisons readily enter the body through the
skin
Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation.
Other cuticle, animal coverings, such as the arthropod exoskeleton, have diffe ...
and
lungs.
Hydrofluoric acid
Hydrofluoric acid is a solution of hydrogen fluoride (HF) in water. Solutions of HF are colourless, acidic and highly corrosive. It is used to make most fluorine-containing compounds; examples include the commonly used pharmaceutical antidepr ...
is a notorious contact poison, in addition to its
corrosive
A corrosive substance is one that will damage or destroy other substances with which it comes into contact by means of a chemical reaction.
Etymology
The word ''corrosive'' is derived from the Latin verb ''corrodere'', which means ''to gnaw'', ...
damage. Naturally occurring
sour gas is a notorious, fast-acting atmospheric poison (as released by
volcanic activity or
drilling rig
A drilling rig is an integrated system that Drilling, drills wells, such as oil or water wells, or holes for piling and other construction purposes, into the earth's subsurface. Drilling rigs can be massive structures housing equipment used to ...
s). Plant-based contact irritants, such as that possessed by
poison ivy or
poison oak, are often classed as
allergen
An allergen is a type of antigen that produces an abnormally vigorous immune response in which the immune system fights off a perceived threat that would otherwise be harmless to the body. Such reactions are called allergies.
In technical ter ...
s rather than poisons; the effect of an allergen being not a poison as such, but to turn the body's
natural defenses against itself. Poison can also enter the body through faulty
medical implants, or by
injection (which is the basis of
lethal injection in the context of
capital punishment
Capital punishment, also known as the death penalty, is the state-sanctioned practice of deliberately killing a person as a punishment for an actual or supposed crime, usually following an authorized, rule-governed process to conclude that ...
).
In 2013, 3.3 million cases of unintentional human poisonings occurred. This resulted in 98,000 deaths worldwide, down from 120,000 deaths in 1990.
In modern society, cases of
suspicious death elicit the attention of the
Coroner's office and
forensic investigators.
Of increasing concern since the isolation of natural
radium
Radium is a chemical element with the symbol Ra and atomic number 88. It is the sixth element in group 2 of the periodic table, also known as the alkaline earth metals. Pure radium is silvery-white, but it readily reacts with nitrogen (rathe ...
by
Marie and
Pierre Curie in 1898—and the subsequent advent of
nuclear physics
Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions, in addition to the study of other forms of nuclear matter.
Nuclear physics should not be confused with atomic physics, which studies the ...
and nuclear technologies—are
radiological poisons. These are associated with
ionizing radiation, a mode of toxicity quite distinct from chemically active poisons. In
mammals, chemical poisons are often passed from mother to offspring through the
placenta
The placenta is a temporary embryonic and later fetal organ (anatomy), organ that begins embryonic development, developing from the blastocyst shortly after implantation (embryology), implantation. It plays critical roles in facilitating nutrien ...
during gestation, or through
breast milk
Breast milk (sometimes spelled as breastmilk) or mother's milk is milk produced by mammary glands located in the breast of a human female. Breast milk is the primary source of nutrition for newborns, containing fat, protein, carbohydrates (lac ...
during
nursing
Nursing is a profession within the health care sector focused on the care of individuals, families, and communities so they may attain, maintain, or recover optimal health and quality of life. Nurses may be differentiated from other health ...
. In contrast, radiological damage can be passed from mother or father to offspring through genetic
mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, m ...
, which—if not fatal in
miscarriage or
childhood, or a direct cause of
infertility—can then be passed along again to a subsequent generation. Atmospheric
radon is a natural radiological poison of increasing impact since humans moved from
hunter-gatherer lifestyles though
cave dwelling to increasingly enclosed structures able to
contain radon in dangerous concentrations. The 2006
poisoning of Alexander Litvinenko
A poison can be any substance that is harmful to the body. It can be swallowed, inhaled, injected or absorbed through the skin. Poisoning is the harmful effect that occurs when too much of that substance has been taken. Poisoning is not t ...
was a novel use of radiological assassination, presumably meant to evade the normal investigation of chemical poisons.
Poisons widely dispersed into the environment are known as
pollution
Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the ...
. These are often of
human origin, but pollution can also include unwanted biological processes such as toxic
red tide
A harmful algal bloom (HAB) (or excessive algae growth) is an algal bloom that causes negative impacts to other organisms by production of natural phycotoxin, algae-produced toxins, mechanical damage to other organisms, or by other means. HABs are ...
, or acute changes to the natural chemical environment attributed to
invasive species
An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species adv ...
, which are toxic or detrimental to the prior ecology (especially if the prior ecology was associated with human economic value or an established industry such as
shellfish harvesting).
The scientific disciplines of
ecology
Ecology () is the study of the relationships between living organisms, including humans, and their physical environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere level. Ecology overl ...
and
environmental resource management study the environmental life cycle of toxic compounds and their complex, diffuse, and highly interrelated effects.
Etymology
The word "poison" was first used in 1200 to mean "a deadly potion or substance"; the English term comes from the "...Old French poison, puison (12c., Modern French poison) "a drink", especially a medical drink, later "a (magic) potion, poisonous drink" (14c.), from Latin potionem (nominative potio) "a drinking, a drink", also "poisonous drink" (Cicero), from potare "to drink".
The use of "poison" as an adjective ("poisonous") dates from the 1520s. Using the word "poison" with plant names dates from the 18th century. The term "
poison ivy", for example, was first used in 1784 and the term "poison oak" was first used in 1743. The term "
poison gas" was first used in 1915.
Terminology
The term "poison" is often used
colloquial
Colloquialism (), also called colloquial language, everyday language or general parlance, is the linguistic style used for casual (informal) communication. It is the most common functional style of speech, the idiom normally employed in convers ...
ly to describe any harmful substance—particularly
corrosive
A corrosive substance is one that will damage or destroy other substances with which it comes into contact by means of a chemical reaction.
Etymology
The word ''corrosive'' is derived from the Latin verb ''corrodere'', which means ''to gnaw'', ...
substances,
carcinogen
A carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis (the formation of cancer). This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes. Several radioactive subst ...
s,
mutagens,
teratogens and harmful
pollutant
A pollutant or novel entity is a substance or energy introduced into the environment that has undesired effects, or adversely affects the usefulness of a resource. These can be both naturally forming (i.e. minerals or extracted compounds like o ...
s, and to exaggerate the dangers of chemicals.
Paracelsus (1493–1541), the father of
toxicology, once wrote: "Everything is poison, there is poison in everything.
Only the dose makes a thing not a poison"
(see
median lethal dose). The term "poison" is also used in a figurative sense: "His brother's presence poisoned the atmosphere at the party". The law defines "poison" more strictly. Substances not legally required to carry the label "poison" can also cause a medical condition of poisoning.
Some poisons are also toxins, which is any poison produced by animals, vegetables or bacteria, such as the
bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were am ...
l
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respon ...
s that cause
tetanus and
botulism
Botulism is a rare and potentially fatal illness caused by a toxin produced by the bacterium '' Clostridium botulinum''. The disease begins with weakness, blurred vision, feeling tired, and trouble speaking. This may then be followed by weakn ...
. A distinction between the two terms is not always observed, even among scientists. The derivative forms "toxic" and "poisonous" are synonymous. Animal poisons delivered
subcutaneously
The subcutaneous tissue (), also called the hypodermis, hypoderm (), subcutis, superficial fascia, is the lowermost layer of the integumentary system in vertebrates. The types of cells found in the layer are fibroblasts, adipose cells, and ma ...
(e.g., by
sting or
bite) are also called ''venom''. In normal usage, a poisonous organism is one that is harmful to consume, but a venomous organism uses venom to kill its prey or defend itself while still alive. A single organism can be both poisonous and venomous, but that is rare.
All living things produce substances to protect them from getting eaten, so the term "poison" is usually only used for substances which are poisonous to humans, while substances that mainly are poisonous to a common pathogen to the organism and humans are considered
antibiotic
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting pathogenic bacteria, bacterial infections, and antibiotic medications are widely used in the therapy, ...
s. Bacteria are for example a common adversary for ''
Penicillium chrysogenum
''Penicillium chrysogenum'' (formerly known as ''Penicillium notatum'') is a species of fungus in the genus ''Penicillium''. It is common in temperate and subtropical regions and can be found on salted food products, but it is mostly found in i ...
'' mold and humans, and since the mold's poison only targets bacteria humans may use it for getting rid of bacteria in their bodies. Human
antimicrobial peptides which are toxic to viruses, fungi, bacteria and cancerous cells are considered a part of the immune system.
In
nuclear physics
Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions, in addition to the study of other forms of nuclear matter.
Nuclear physics should not be confused with atomic physics, which studies the ...
, a
poison is a substance that obstructs or inhibits a nuclear reaction.
Environmentally hazardous substances are not necessarily poisons, and vice versa. For example, food-industry wastewater—which may contain potato juice or milk—can be hazardous to the ecosystems of streams and rivers by consuming oxygen and causing
eutrophication
Eutrophication is the process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients, particularly nitrogen and phosphorus. It has also been defined as "nutrient-induced increase in phytopla ...
, but is nonhazardous to humans and not classified as a poison.
Biologically speaking, any substance, if given in large enough amounts, is poisonous and can cause death. For instance, several kilograms worth of water would constitute a lethal dose. Many substances used as medications—such as
fentanyl—have an only one order of magnitude greater than the
ED50. An alternative classification distinguishes between lethal substances that provide a therapeutic value and those that do not.
Poisoning
Poisoning can be either acute or chronic, and caused by a variety of natural or synthetic substances. Substances that destroy tissue but do not absorb, such as
lye, are classified as
corrosive
A corrosive substance is one that will damage or destroy other substances with which it comes into contact by means of a chemical reaction.
Etymology
The word ''corrosive'' is derived from the Latin verb ''corrodere'', which means ''to gnaw'', ...
s rather than poisons.
Acute
Acute poisoning is exposure to a poison on one occasion or during a short period of time. Symptoms develop in close relation to the exposure. Absorption of a poison is necessary for systemic poisoning. Furthermore, many common household medications are not labeled with skull and crossbones, although they can cause severe illness or even death. Poisoning can be caused by excessive consumption of generally safe substances, as in the case of
water intoxication.
Agents that act on the
nervous system
In Biology, biology, the nervous system is the Complex system, highly complex part of an animal that coordinates its Behavior, actions and Sense, sensory information by transmitting action potential, signals to and from different parts of its ...
can paralyze in seconds or less, and include both biologically derived
neurotoxin
Neurotoxins are toxins that are destructive to nerve tissue (causing neurotoxicity). Neurotoxins are an extensive class of exogenous chemical neurological insultsSpencer 2000 that can adversely affect function in both developing and matur ...
s and so-called
nerve gas
Nerve agents, sometimes also called nerve gases, are a class of organic chemicals that disrupt the mechanisms by which nerves transfer messages to organs. The disruption is caused by the blocking of acetylcholinesterase (AChE), an enzyme tha ...
es, which may be synthesized for
warfare
War is an intense armed conflict between State (polity), states, governments, Society, societies, or paramilitary groups such as Mercenary, mercenaries, Insurgency, insurgents, and militias. It is generally characterized by extreme violenc ...
or industry.
Inhaled or ingested
cyanide
Cyanide is a naturally occurring, rapidly acting, toxic chemical that can exist in many different forms.
In chemistry, a cyanide () is a chemical compound that contains a functional group. This group, known as the cyano group, consists of ...
, used as a method of
execution in
gas chambers, or as a
suicide method, almost instantly starves the body of energy by
inhibiting the
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecule ...
s in
mitochondria that make
ATP
ATP may refer to:
Companies and organizations
* Association of Tennis Professionals, men's professional tennis governing body
* American Technical Publishers, employee-owned publishing company
* ', a Danish pension
* Armenia Tree Project, non ...
. Intravenous injection of an unnaturally high concentration of
potassium chloride
Potassium chloride (KCl, or potassium salt) is a metal halide salt composed of potassium and chlorine. It is odorless and has a white or colorless vitreous crystal appearance. The solid dissolves readily in water, and its solutions have a sa ...
, such as in the execution of prisoners in parts of the United States, quickly stops the
heart
The heart is a muscular organ found in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon diox ...
by eliminating the
cell potential necessary for
muscle contraction.
Most biocides, including
pesticides, are created to act as acute poisons to target organisms, although acute or less observable chronic poisoning can also occur in non-target organisms (
secondary poisoning), including the
human
Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...
s who apply the biocides and other
beneficial organisms. For example, the herbicide
2,4-D imitates the action of a plant hormone, which makes its lethal toxicity specific to plants. Indeed, 2,4-D is not a poison, but classified as "harmful" (EU).
Many substances regarded as poisons are toxic only indirectly, by
toxication. An example is "wood alcohol" or
methanol, which is not poisonous itself, but is chemically converted to toxic
formaldehyde and
formic acid
Formic acid (), systematically named methanoic acid, is the simplest carboxylic acid, and has the chemical formula HCOOH and structure . It is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. Est ...
in the
liver
The liver is a major organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the synthesis of proteins and biochemicals necessary for digestion and growth. In humans, it ...
. Many
drug
A drug is any chemical substance that causes a change in an organism's physiology or psychology when consumed. Drugs are typically distinguished from food and substances that provide nutritional support. Consumption of drugs can be via inhal ...
molecules are made toxic in the liver, and the genetic variability of certain liver
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecule ...
s makes the toxicity of many compounds differ between individuals.
Exposure to radioactive substances can produce
radiation poisoning, an unrelated phenomenon.
Two common cases of acute natural poisoning are
theobromine poisoning of
dogs and
cat
The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of ...
s, and
mushroom poisoning in humans. Dogs and cats are not natural herbivores, but a chemical defense developed by ''
Theobroma cacao
''Theobroma cacao'', also called the cacao tree and the cocoa tree, is a small ( tall) evergreen tree in the family Malvaceae. Its seeds, cocoa beans, are used to make chocolate liquor, cocoa solids, cocoa butter and chocolate. The largest ...
'' can be incidentally fatal nevertheless. Many omnivores, including humans, readily consume edible
fungi
A fungus (plural, : fungi or funguses) is any member of the group of Eukaryote, eukaryotic organisms that includes microorganisms such as yeasts and Mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified ...
, and thus many fungi have evolved to become
decisively inedible, in this case as a direct defense.
Chronic
Chronic poisoning is long-term repeated or continuous exposure to a poison where symptoms do not occur immediately or after each exposure. The person gradually becomes ill, or becomes ill after a long latent period. Chronic poisoning most commonly occurs following exposure to poisons that
bioaccumulate, or are
biomagnified, such as
mercury,
gadolinium, and
lead
Lead is a chemical element with the Symbol (chemistry), symbol Pb (from the Latin ) and atomic number 82. It is a heavy metals, heavy metal that is density, denser than most common materials. Lead is Mohs scale of mineral hardness#Intermediate ...
.
Management
* Initial management for all poisonings includes ensuring adequate
cardiopulmonary function and providing treatment for any symptoms such as
seizures,
shock, and
pain
Pain is a distressing feeling often caused by intense or damaging stimuli. The International Association for the Study of Pain defines pain as "an unpleasant sensory and emotional experience associated with, or resembling that associated with, ...
.
* Injected poisons (e.g., from the sting of animals) can be treated by binding the affected body part with a
pressure bandage and placing the affected body part in hot water (with a temperature of 50 °C). The pressure bandage prevents the poison being pumped throughout the body, and the hot water breaks it down. This treatment, however, only works with poisons composed of protein-molecules.
* In the majority of poisonings the mainstay of management is providing supportive care for the patient, i.e., treating the symptoms rather than the poison.
Decontamination
* Treatment of a recently ingested poison may involve gastric decontamination to decrease absorption. Gastric decontamination can involve
activated charcoal,
gastric lavage,
whole bowel irrigation, or
nasogastric aspiration. Routine use of emetics (
syrup of Ipecac),
cathartics or laxatives are no longer recommended.
**
Activated charcoal is the treatment of choice to prevent poison absorption. It is usually administered when the patient is in the emergency room or by a trained emergency healthcare provider such as a Paramedic or EMT. However, charcoal is ineffective against
metal
A metal (from Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typi ...
s such as
sodium
Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable ...
,
potassium
Potassium is the chemical element with the symbol K (from Neo-Latin '' kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosp ...
, and
lithium, and
alcohols and
glycols; it is also not recommended for ingestion of corrosive chemicals such as
acids and
alkalis.
**
Cathartics were postulated to decrease absorption by increasing the expulsion of the poison from the
gastrointestinal tract. There are two types of cathartics used in poisoned patients; saline cathartics (
sodium sulfate,
magnesium citrate,
magnesium sulfate) and saccharide cathartics (
sorbitol). They do not appear to improve patient outcome and are no longer recommended.
**
Emesis
Vomiting (also known as emesis and throwing up) is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose.
Vomiting can be the result of ailments like food poisoning, gastroenteri ...
(i.e. induced by
ipecac) is no longer recommended in poisoning situations, because vomiting is ineffective at removing poisons.
**
Gastric lavage, commonly known as a stomach pump, is the insertion of a tube into the stomach, followed by administration of water or saline down the tube. The liquid is then removed along with the contents of the stomach. Lavage has been used for many years as a common treatment for poisoned patients. However, a recent review of the procedure in poisonings suggests no benefit.
It is still sometimes used if it can be performed within 1 hour of ingestion and the exposure is potentially life-threatening.
**
Nasogastric aspiration involves the placement of a tube via the nose down into the stomach, the stomach contents are then removed by suction. This procedure is mainly used for liquid ingestions where activated charcoal is ineffective, e.g.
ethylene glycol poisoning.
**
Whole bowel irrigation cleanses the bowel. This is achieved by giving the patient large amounts of a
polyethylene glycol
Polyethylene glycol (PEG; ) is a polyether compound derived from petroleum with many applications, from industrial manufacturing to medicine. PEG is also known as polyethylene oxide (PEO) or polyoxyethylene (POE), depending on its molecular w ...
solution. The osmotically balanced polyethylene glycol solution is not absorbed into the body, having the effect of flushing out the entire
gastrointestinal tract. Its major uses are to treat ingestion of sustained release drugs, toxins not absorbed by activated charcoal (e.g.,
lithium,
iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in ...
), and for removal of ingested drug packets (
body packing/smuggling).
Enhanced excretion
* In some situations elimination of the poison can be enhanced using
diuresis,
hemodialysis
Hemodialysis, also spelled haemodialysis, or simply dialysis, is a process of purifying the blood of a person whose kidneys are not working normally. This type of dialysis achieves the extracorporeal removal of waste products such as creatinin ...
,
hemoperfusion,
hyperbaric medicine,
peritoneal dialysis,
exchange transfusion
An exchange transfusion is a blood transfusion in which the patient's blood or components of it are exchanged with (replaced by) other blood or blood products. The patient's blood is removed and replaced by donated blood or blood components. This ...
or
chelation. However, this may actually worsen the poisoning in some cases, so it should always be verified based on what substances are involved.
Epidemiology
In 2010, poisoning resulted in about 180,000 deaths down from 200,000 in 1990.
There were approximately 727,500 emergency department visits in the United States involving poisonings—3.3% of all injury-related encounters.
Applications
Poisonous compounds may be useful either for their toxicity, or, more often, because of another chemical property, such as specific chemical reactivity. Poisons are widely used in industry and agriculture, as chemical reagents, solvents or complexing reagents, e.g.
carbon monoxide
Carbon monoxide ( chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the si ...
,
methanol and
sodium cyanide
Sodium cyanide is a poisonous compound with the formula Na C N. It is a white, water-soluble solid. Cyanide has a high affinity for metals, which leads to the high toxicity of this salt. Its main application, in gold mining, also exploits its h ...
, respectively. They are less common in household use, with occasional exceptions such as
ammonia
Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogeno ...
and
methanol. For instance,
phosgene
Phosgene is the organic chemical compound with the formula COCl2. It is a toxic, colorless gas; in low concentrations, its musty odor resembles that of freshly cut hay or grass. Phosgene is a valued and important industrial building block, es ...
is a highly reactive
nucleophile acceptor, which makes it an excellent reagent for polymerizing
diols and
diamines to produce
polycarbonate and
polyurethane
Polyurethane (; often abbreviated PUR and PU) refers to a class of polymers composed of organic chemistry, organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethan ...
plastics. For this use, millions of tons are produced annually. However, the same reactivity makes it also highly reactive towards proteins in human tissue and thus highly toxic. In fact, phosgene has been used as a
chemical weapon. It can be contrasted with
mustard gas
Mustard gas or sulfur mustard is a chemical compound belonging to a family of cytotoxic and blister agents known as mustard agents. The name ''mustard gas'' is technically incorrect: the substance, when dispersed, is often not actually a gas, b ...
, which has only been produced for chemical weapons uses, as it has no particular industrial use.
Biocides need not be poisonous to humans, because they can target metabolic pathways absent in humans, leaving only incidental toxicity. For instance, the herbicide
2,4-dichlorophenoxyacetic acid is a mimic of a plant growth hormone, which causes uncontrollable growth leading to the death of the plant. Humans and animals, lacking this hormone and its receptor, are unaffected by this, and need to ingest relatively large doses before any toxicity appears. Human toxicity is, however, hard to avoid with pesticides targeting mammals, such as
rodenticides.
The risk from toxicity is also distinct from toxicity itself. For instance, the preservative
thiomersal
Thiomersal ( INN), or thimerosal ( USAN, JAN), is an organomercury compound. It is a well-established antiseptic and antifungal agent.
The pharmaceutical corporation Eli Lilly and Company gave thiomersal the trade name Merthiolate. It has bee ...
used in vaccines is toxic, but the quantity administered in a single shot is negligible.
File:Poisonings world map-Deaths per million persons-WHO2012.svg, upright=1.3, Deaths from poisonings per million persons in 2012
Image:Poisonings world map - DALY - WHO2004.svg, Disability-adjusted life year for poisonings per 100,000 inhabitants in 2004.
History
Throughout human history, intentional application of poison has been used as a method of
murder,
pest-control
Pest control is the regulation or management of a species defined as a pest (organism), pest; any animal, plant or fungus that impacts adversely on human activities or environment. The human response depends on the importance of the damage don ...
,
suicide, and
execution. As a method of execution, poison has been ingested, as the ancient Athenians did (see
Socrates
Socrates (; ; –399 BC) was a Greek philosopher from Athens who is credited as the founder of Western philosophy and among the first moral philosophers of the ethical tradition of thought. An enigmatic figure, Socrates authored no te ...
), inhaled, as with
carbon monoxide
Carbon monoxide ( chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the si ...
or
hydrogen cyanide
Hydrogen cyanide, sometimes called prussic acid, is a chemical compound with the formula HCN and structure . It is a colorless, extremely poisonous, and flammable liquid that boils slightly above room temperature, at . HCN is produced on a ...
(see
gas chamber), injected (see
lethal injection), or even as an
enema. Poison's lethal effect can be combined with its allegedly
magical powers; an example is the
Chinese ''gu'' poison. Poison was also employed in
gunpowder warfare. For example, the 14th-century Chinese text of the ''
Huolongjing'' written by
Jiao Yu outlined the use of a poisonous gunpowder mixture to fill
cast iron
Cast iron is a class of iron– carbon alloys with a carbon content more than 2%. Its usefulness derives from its relatively low melting temperature. The alloy constituents affect its color when fractured: white cast iron has carbide impu ...
grenade
A grenade is an explosive weapon typically thrown by hand (also called hand grenade), but can also refer to a shell (explosive projectile) shot from the muzzle of a rifle (as a rifle grenade) or a grenade launcher. A modern hand grenade g ...
bombs.
[Needham, Joseph (1986). ''Science and Civilization in China: Volume 5, Part 7''. Taipei: Caves Books, Ltd. Page 180.]
While
arsenic
Arsenic is a chemical element with the symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a metalloid. It has various allotropes, bu ...
is a naturally occurring environmental poison, its artificial concentrate was once nicknamed
inheritance powder.
In
Medieval
In the history of Europe, the Middle Ages or medieval period lasted approximately from the late 5th to the late 15th centuries, similar to the post-classical period of global history. It began with the fall of the Western Roman Empire a ...
Europe, it was common for
monarch
A monarch is a head of stateWebster's II New College DictionarMonarch Houghton Mifflin. Boston. 2001. p. 707. Life tenure, for life or until abdication, and therefore the head of state of a monarchy. A monarch may exercise the highest authority ...
s to employ personal
food tasters to thwart royal
assassination
Assassination is the murder of a prominent or important person, such as a head of state, head of government, politician, world leader, member of a royal family or CEO. The murder of a celebrity, activist, or artist, though they may not have a ...
, in the dawning age of the
Apothecary
''Apothecary'' () is a mostly archaic term for a medical professional who formulates and dispenses '' materia medica'' (medicine) to physicians, surgeons, and patients. The modern chemist (British English) or pharmacist (British and North Amer ...
.
Figurative use
The term poison is also used in a figurative sense. The slang sense of alcoholic drink is first attested 1805, American English. (e.g., a bartender might ask a customer "what's your poison?" or "Pick your poison")
Figurative use of the term dates from the late 15th century.
Figuratively referring to persons as poison dates from 1910.
The figurative term poison-pen letter became well known in ...1913 by a notorious criminal case in Pennsylvania, U.S.; the phrase dates to 1898.
See also
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References
External links
National Capital Poison CenterwebPOISONCONTROL(R)Agency for Toxic Substances and Disease RegistryAmerican Association of Poison Control CentersAmerican College of Medical ToxicologyClinical Toxicology Teaching Wiki
Find Your Local Poison Control Centre Here (Worldwide)Poison Prevention and Education WebsiteCochrane Injuries Group Systematic reviews on the prevention, treatment and rehabilitation of traumatic injury (including poisoning)
Pick Your Poison—12 Toxic Talesby Cathy Newman
{{Authority control
Execution equipment
Execution methods
Suicide methods