Poison

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In biology, poisons are substances that cause injury, illness or death of organisms by a chemical reaction, at the molecular level. This definition excludes physical agents, of small size (a clot, a bubble of air in the blood, an electrical current, radiation, etc.). Some poisons are also toxins, and the distinction between these two terms is not always observed even among scientists. According to the observation of Paracelsus, all substances are, high-dose toxins. Most needed, such as water, oxygen, vitamins. By contrast, substances considered poison beyond certain doses, can have interesting pharmacological properties. For example, at low doses, arsenic oxide can cure the Lupus. Most effective anti-infective drugs, such as antibiotics, are poisons and their dosage is calculated to destroy the infectious agent without endangering the life of the patient. The contre-poisons can also be dangerous, but their antagonism cancels the toxic effects of each of the two molecules.

Is generally reserved as the poison to those acting dose very low (lower than the thousandth or the millionth mass report).

The study of symptoms, mechanisms of action, treatment and diagnosis of biological poisons is called toxicology.

Chemistry has generalized the notion of poison of poison of catalyst: it is a substance that blocks or inhibits a reaction, often by binding to a catalyst more strongly than normal reagent. For example, the species contained lead quickly blocking the functioning of catalytic exhaust converters, which was compelled to reformulate gasoline.

The great unity of the processes used by living species is that many poisons have effects on many species, even if the sensitivity is highly variable from one species to another.

Most species produce poisons for themselves, and organize themselves accordingly.

Broad categories of poisons

There are three broad categories of poisons:

• chemical poisons, arsenic, cyanide, phenol, sarin, phosgene…;
• organic poisons (batrachotoxin, curare, botulinum toxin muscarine, ricin, tétraodontoxine…);
• physical poisons (radionuclides: radiation alpha, beta, gamma).

The poison can be gaseous, liquid or solid. It may act by contact (dermal absorption), by inhalation, ingestion or injection. There are natural Poisons (gas, minerals, alkaloids, venom…) and poisons created by man.

There are also wounds toxics (paraquat, colchicine…) of functional toxics (antiarrhythmic drugs, antidepressants, Tricyclic, barbiturates, carbamates, chloroquine, digitaline, theophylline…).

Classes of poisons

• Nerve (the synaptic junction… inhibitor): the nerve affect nerve, prevent motor coordination, and block some critical muscles (respiratory muscle, heart). The best known are curare, neurotoxins, and nerve gases. many insecticides belong to this class. Most often, their target is the interface between the nerve cell and the next cell (nerve or muscle);
• Poisons necrotising and poisons hémolysants: living cells are full to overflowing, pockets who do that thanks to a frame, a net composed of lipids and proteins that the cell maintains permanently. Some poisons destroy these nets, in catalysing and accelerating its decay, either by taking the place of elements but without the strength of the whole;
• ATP synthesis inhibitor: living cells work with the energy of ATP, provided by the mitochondria. Cyanides block the synthesis of ATP, which in seconds deprive these cells of all energy, stopping all syntheses and any motor activity and killing quickly;
• inhibitor of the muscular junction: potassium chloride causes an interruption of the heart by preventing the creation of the cell potential contraction of muscles. It is this last poison used in some States of United States to execute prisoners sentenced to death;
• cumulative poison: poison may also act slowly by accumulation. For example, mercury, lead and other heavy metals, benzene and other aromatic compounds;
• mutagenic poison and poisons allergens: Finally, asbestos (causing cancer of the lungs and pleura), many dust (sawdust, dust of Earth and coal), allergens, have harmful effects which the occurrence is not certain, but more or less likely depending on the dose and the frequency of exposure, and according to the sensitivity of the person.

Many substances regarded as poisons are actually poisons precursors: is the body itself which turns them into poisons. For example, methanol is not toxic, but is converted to methanal in the liver.

(See also types of toxins in the venom article).

Types of damage

Contact or ingestion of a poison may cause damage:

• Although temporary (including death) or irreversible;
• partial and localized, or well widespread;
• quickly, or rather slowly.
• with certainty, or with a certain probability (increasing with dose).

(See also the types of damages in section venom).

Resistance to poisons

Poisons are so present that life would be impossible without poison. Different solutions are adopted by human beings live:

• excretion, i.e. the evacuation (urine, sweat, breathing, etc.). This mechanism is very used to the poisons of internal origin, present synthesis and in large quantity (urea, oxygen to the plants or carbon dioxide for animals, etc.).
• chemical destruction (but has been seen, the cure can be worse than the disease, if the destruction products are more toxic). Most organizations have a body specialized in the treatment of the incoming molecules (such as liver). This allows to reduce the concentration in sometimes sufficient proportions for the shock.
• the concentration in a body chemically little mobilized (cells of adipose storage, shells or bones).
• the self-mutilation: rather than having a body performance but sensitive to some poison, the organization prefers do without using a system less efficient but more suited to the context (which does not mean more robust in absolute terms). It is the mechanism of resistance of microbes to antibiotics.

The mithridatism is to interfere with increasing doses of toxic to acquire an insensitivity or resistance to it. The King of the ancient Mithridates was thus to prevent the risks associated with poisoning which he feared he would be the victim.

The effects of the poison varies also with the resistance of the victim.

Latency period

Some poisons can smash, acting in a few minutes, others in a few hours, others a few days, or several weeks, finally some acting long term (six months to a year, with a long period of latency – as for example with asbestos, because of very long times of development of cancer of the pleura (mesothelioma).) This last period for asbestos clearly exceed the twenty years, in the majority of cases of mesothelioma.

The latency period – designating the period without symptoms or the time after which the poison is its effect-, can be highly variable from one poison to another and may depend on other factors (resistance to poison…), most of the poisons do not effect immediately, insofar as they must first be assimilated by the body.

Lethal doses

Lethal doses can be highly variable, ranging from quantities per gram in the picogram below.

In toxicology, the lethal dose (LD50, dose per kilogram of fresh weight) represent doses that result in the death of half of human beings or living organisms present in a sample.

Detection of poisons

The techniques used to detect poisons depending on their nature. Physico-chemical analyses may use the electrochemical, chromatographic and spectrometric, for example a chromatography coupled with mass spectrometry.

Use of poisons

in the nature

No poisons, life as we know it would not exist. All living species widely use poisons:

• to defend themselves, especially against microorganisms (antibiotics, lysozyme) or other living organisms (poisonous plants, poisonous animals, etc.) it is important here to distinguish between “Ivy” which applies to plants and “venomous” (for venom) which applies to the animals
• to defend their territory and their source of food against competition (désherbantes plants, mycotoxins);
• to obtain an offensive capability much more and more economic than brute physical force (poisonous snakes).

by human industry

Human spreading wide poisons this time with a genuine desire and an awareness of the goals (but sometimes, however, a real unconsciousness of the consequences):

• eliminate parasites (lice, mosquitoes);
• eliminate competitors (insects and fungi pests of crops, “weeds”);
• to care for themselves, or get stoned (the word drug indicates the proximity of phenomena), or still dope.
• Select species, by combining with a useful character poison resistance;
• kill, war: weapons chemical (gas-attack…) or bacteriological (see chemical weapon, see NBC weapons);
• etc.

in crimes

• political assassinations (for example, assassinations of political opponents).
• murders of competitors (political, economic…).
• murders of people uncomfortable (witnesses…).
• killings by interest (family in transmissions of estates, to benefit from the inheritance…).
• murder hate, passion…
• to be able to separate from her husband, before the divorce Act, adopted in France, July 27, 1884,
• in crimes of masses (in genocide of the Jews by the nazis practiced in Nazi extermination camps, using Zyklon B which emits… hydrogen cyanide).
• to test on humans of new substances or new poisons human (criminal experiments, in particular biological poisons, the Japanese Unit 731, from 1932 to 1945, Kizu and Shanzi in Manchuria (China), experimenting with poisons on detainees, by Guépéou or GPU, as early as 1938, at the instigation of Béria, criminal of Nazi medical experimentation, on the prisoners)(, in some camps of concentration…).

Famous poisonings

• Socrates: Accused of distorting the young Athenians by his ideology, sentenced to death by the Areopagus of Athens, drank a decoction to base of hemlock, assisted by his servant (e) s (in fact the story in the Phaedo Plato).
• Britannicus
• Agnès Sorel

• Napoleon Bonaparte: A theory prevailed there is still little, imagining that he was murdered by arsenic, because the FBI was discovered in 1961 in his hair “compatible with poisoning” arsenic rates: legend that Napoleon has died of poisoning by a relative. Current theory says that the arsenic came instead from a hair treatment product, and would in fact died of gastric bleeding caused by cancer of the stomach, quite consistent with his family history and the testimony of relatives.
• Charles Darwin: Would be poisoned by self-medication of a solution containing one percent of arsenic, while this is only a rumour (in fact, he would have suffered for more than 20 years, of Chagas disease, a disease and infection caused by the parasite Trypanosoma cruzi (American Trypanosomiasis) caused by bedbugs hémophages of the genus Triatoma, Darwin was himself caught in March 1835)(, in Chile, by a Pushpin to transmit this infection);

• Rasputin: Resisted a massive dose of cyanide (due to the reaction of the cyanide with the sugar for cakes that contained) and therefore ultimately murdered more brutally than bullets.

• Alan Turing: Suicide is by painting an Apple of cyanide that he bit then;
• Georgi Markov (Georgi Ivanov Markov): Dissident Bulgarian, murdered in London in September, 1978, by agents of the Bulgarian secret police and a special umbrella (nicknamed “Bulgarian umbrella”), which threw him in the calf a ball made of an alloy of Platinum and iridium, ricin-coated.
• Munir Said Thalib (or see also Munir Said Thalib, on the Wikipedia encyclopedia in English): A prominent Indonesian human rights defender, died 7 September 2004 after having ingested arsenic on a plane from Jakarta to Amsterdam.
• Viktor Yushchenko: President of the Republic of Ukraine since January 23, 2005, head of the political coalition “Our Ukraine” (Nasha Ukrayina) since 2002, whose face is remained hailed by chloric acne, is poisoned in 2004, tetrachlorodibenzodioxin (TCDD) or “Seveso dioxin”, in the election campaign against Viktor Yanukovych.
• Alexander Litvinenko: Russian Ex-espion emigrated to England, was poisoned with polonium-210 in November 2006.
• Case of the poisoned Josacine: in 1994 Jean-Marc Deperrois was sentenced by the Court of Assizes of Seine-Maritime for poisoning of a child of eight years, Émilie Taney, with antibiotic syrup (Josacine) poisoned with cyanide. The trial shows that the child was apparently not the intended recipient of the poison.

In France, Lafarge and Besnard Affairs are the two most famous cases of poisoning.

Famous poisoners

• Agrippina the younger, daughter of Germanicus and mother of Nero, is murdering her second husband Passienus Crispus, immensely rich, to bind to the Claude Emperor, his uncle. Then she poisoned Emperor Claude, October 13, 54, with a toxicodendron radicans named locust (according to the Roman writer Suetonius, and his book, lives of the Twelve Caesars).
• Néron, son of Agrippina, is poison his brother Britannicus (according to the Roman writer Suetonius, and his book, lives of the Twelve Caesars).
• Charles II of Navarre, said Charles the bad.
• The Borgia family:
  • Pope Alexander VI, Roderic de Borgia (though this is a rumour). He died in having drank poisoned wine.
  • Caesar, son of Roderic Borgia.
• Catherine Deshayes, said the neighbor (see case of poisons).
• Marie Lafarge: was accused of having poisoned her husband. Ordered in 1840 to forced labour for life, was released but this case remains a judicial Enigma: the husband would in fact probably died of typhoid.
• the affair of the poisons: famous case at the time of a series of poisonings in Paris and at the Royal Court, involving the Marquise de Brinvilliers under Louis XIV, Madame de Montespan,…
• Hélène Jégado: sentenced to death in 1851 in Rennes for 3 murders and 3 attempts. Suspected about 36 poisonings arsenic;
• Marie Besnard: nicknamed “the toxicodendron radicans of Loudun”. She was accused of having poisoned twelve people arsenic, for a purpose purely estate and financial. It was paid, and some scientists still put his guilt into question. According to some:
  • methods of measurement of rate of arsenic, at the time, on the exhumed skeletons were unreliable.
  • these skeletons could be contaminated by arsenic from the weed control, used in cemeteries, in the 1950s.
  • most of the people who have made a donation to Marie Besnard had reached an age at death.
  • the amounts of these gifts were generally very small.

Poisoning in the literature

• The poison takes an important place in several plays of William Shakespeare: Hamlet and Romeo and Juliet for example.

• Gustave Flaubert described the suicide to arsenic of the main character in the novel Madame Bovary.

• In the novel the name of the rose Umberto Eco, the character of Jorge de Burgos makes use of a poison.

• In the count of Monte – Cristo, Valentine de Villefort is poisoned by his stepmother who wants to hand-bass on the legacy of grandfather (and grandmother) of Valentine, but it mithridatisait Valentine for a few years and she survives.

• Poisonings are blossoming in the novels: the mirror crack, death in the clouds, drama in three acts, the sign of the four, ten little Niggers, etc.

• In the gesture of the Princes – demons, cycle of science fiction in 5 volumes written by the American author Jack Vance, the originating Sarkoys of the planet Sarkovy are for masters poisoners who exercise their talents for a fee. Their preferred poison is the kluthe, kills by simple contact, rapidly or very slowly with the chosen dosage. A scene of the kluthe poisoning is related in the first episode of the series, “The Prince of the stars”.

• The Borgia recipe by Voltaire:

“The drooling of a pig made rabid by the suspending upside down by the feet, and long time beating it to death.” [...] It seems that the poison of the Borgia was a mixture of arsenious acid and reeking alkaloids. Thus preparing: it sacrificed a pig, it includes arsenious acid abdominal organs, and expected that the decomposition – delayed by arsenic – was complete. Then, depending on whether there are to use it as a powder or drops, it had more than dry rotten mass or to collect liquids. »

“Nothing is poison, is poison: the dose makes the poison.” Most popular: “excess night all.” Theophrastus Bombastus von Hohenheim, says Paracelsus

• Count Cain (popular manga series):

The main character, Earl Cain C. Hargreaves, nicknamed the count of Poisons, resolves investigations and mystic crimes (as a supposed spirited people supposedly murdered by curses and ghosts, etc.) in the years around the time of Jack the Ripper, his poisons and his knowledge on them.

• “Between a toxicodendron radicans and a bad stove there is only a difference of intent.” Desproges