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An organochloride, organochlorine compound, chlorocarbon, or chlorinated hydrocarbon is an
organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The ...
containing at least one
covalently bonded A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs. The stable balance of attractive and repulsive forces between atoms ...
atom of
chlorine Chlorine is a chemical element with the Symbol (chemistry), symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate betwee ...
. The chloroalkane class (
alkane In organic chemistry, an alkane, or paraffin (a historical trivial name that also has other meanings), is an acyclic saturated hydrocarbon. In other words, an alkane consists of hydrogen and carbon atoms arranged in a tree structure in which ...
s with one or more hydrogens substituted by chlorine) provides common examples. The wide structural variety and divergent chemical properties of organochlorides lead to a broad range of names, applications, and properties. Organochlorine compounds have wide use in many applications, though some are of profound environmental concern, with
TCDD TCDD may refer to any of the following: * Turkish State Railways The State Railways of the Republic of Turkey ( tr, Türkiye Cumhuriyeti Devlet Demiryolları), abbreviated as TCDD, is a government-owned national railway company responsible with ...
being one of the most notorious.


Physical and chemical properties

Chlorination modifies the physical properties of hydrocarbons in several ways. These compounds are typically denser than
water Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ...
due to the higher atomic weight of chlorine versus hydrogen. Aliphatic organochlorides are often
alkylating agent Alkylation is the transfer of an alkyl group from one molecule to another. The alkyl group may be transferred as an alkyl carbocation, a free radical, a carbanion, or a carbene (or their equivalents). Alkylating agents are reagents for effecting al ...
s as chlorine can act as a leaving group, which can result in cellular damage.


Natural occurrence

Many organochlorine compounds have been isolated from natural sources ranging from bacteria to humans. Chlorinated organic compounds are found in nearly every class of biomolecules and
natural product A natural product is a natural compound or substance produced by a living organism—that is, found in nature. In the broadest sense, natural products include any substance produced by life. Natural products can also be prepared by chemical syn ...
s including
alkaloid Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar ...
s,
terpene Terpenes () are a class of natural products consisting of compounds with the formula (C5H8)n for n > 1. Comprising more than 30,000 compounds, these unsaturated hydrocarbons are produced predominantly by plants, particularly conifers. Terpenes ar ...
s,
amino acid Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha am ...
s,
flavonoid Flavonoids (or bioflavonoids; from the Latin word ''flavus'', meaning yellow, their color in nature) are a class of polyphenolic secondary metabolites found in plants, and thus commonly consumed in the diets of humans. Chemically, flavonoids ...
s,
steroid A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and a ...
s, and
fatty acid In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, fr ...
s.
Dioxins Dioxin may refer to: * 1,2-Dioxin or 1,4-Dioxin, two unsaturated heterocyclic 6-membered rings where two carbon atoms have been replaced by oxygen atoms, giving the molecular formula C4H4O2 *Dibenzo-1,4-dioxin, the parent compound also known as ...
, which are of particular concern to human and environmental health, are produced in the high temperature environment of forest fires and have been found in the preserved ashes of lightning-ignited fires that predate synthetic dioxins. In addition, a variety of simple chlorinated hydrocarbons including
dichloromethane Dichloromethane (DCM or methylene chloride, methylene bichloride) is an organochlorine compound with the formula . This colorless, volatile liquid with a chloroform-like, sweet odour is widely used as a solvent. Although it is not miscible with ...
,
chloroform Chloroform, or trichloromethane, is an organic compound with chemical formula, formula Carbon, CHydrogen, HChlorine, Cl3 and a common organic solvent. It is a colorless, strong-smelling, dense liquid produced on a large scale as a precursor to ...
, and
carbon tetrachloride Carbon tetrachloride, also known by many other names (such as tetrachloromethane, also IUPAC nomenclature of inorganic chemistry, recognised by the IUPAC, carbon tet in the cleaning industry, Halon-104 in firefighting, and Refrigerant-10 in HVAC ...
have been isolated from marine algae. A majority of the chloromethane in the environment is produced naturally by biological decomposition, forest fires, and volcanoes. The natural organochloride
epibatidine Epibatidine is a chlorinated alkaloid that is secreted by the Ecuadoran frog '' Epipedobates anthonyi'' and poison dart frogs from the Ameerega genus. It was discovered by John W. Daly in 1974, but its structure was not fully elucidated until ...
, an alkaloid isolated from tree frogs, has potent
analgesic An analgesic drug, also called simply an analgesic (American English), analgaesic (British English), pain reliever, or painkiller, is any member of the group of drugs used to achieve relief from pain (that is, analgesia or pain management). It ...
effects and has stimulated research into new pain medication. However, because of its unacceptable
therapeutic index The therapeutic index (TI; also referred to as therapeutic ratio) is a quantitative measurement of the relative safety of a drug. It is a comparison of the amount of a therapeutic agent that causes the therapeutic effect to the amount that causes ...
, it is no longer a subject of research for potential therapeutic uses. The frogs obtain epibatidine through their diet which is then sequestered into their skin. Likely dietary sources are beetles, ants, mites, and flies.


Preparation


From chlorine

Alkanes In organic chemistry, an alkane, or paraffin (a historical trivial name that also has other meanings), is an acyclic saturated hydrocarbon. In other words, an alkane consists of hydrogen and carbon atoms arranged in a tree structure in which ...
and
aryl In organic chemistry, an aryl is any functional group or substituent derived from an aromatic ring, usually an aromatic hydrocarbon, such as phenyl and naphthyl. "Aryl" is used for the sake of abbreviation or generalization, and "Ar" is used as ...
alkanes may be chlorinated under free radical conditions, with UV light. However, the extent of chlorination is difficult to control. Aryl chlorides may be prepared by the Friedel-Crafts halogenation, using chlorine and a
Lewis acid A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any sp ...
catalyst. The haloform reaction, using chlorine and
sodium hydroxide Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly caustic base and alkali ...
, is also able to generate alkyl halides from methyl ketones, and related compounds. Chloroform was formerly produced thus. Chlorine adds to the multiple bonds on alkenes and alkynes as well, giving di- or tetra-chloro compounds.


Reaction with hydrogen chloride

Alkenes react with
hydrogen chloride The compound hydrogen chloride has the chemical formula and as such is a hydrogen halide. At room temperature, it is a colourless gas, which forms white fumes of hydrochloric acid upon contact with atmospheric water vapor. Hydrogen chloride ga ...
(HCl) to give alkyl chlorides. For example, the industrial production of
chloroethane Chloroethane, commonly known as ethyl chloride, is a chemical compound with chemical formula CH3CH2Cl, once widely used in producing tetraethyllead, a gasoline additive. It is a colorless, flammable gas or refrigerated liquid with a faintly sweet ...
proceeds by the reaction of
ethylene Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula or . It is a colourless, flammable gas with a faint "sweet and musky" odour when pure. It is the simplest alkene (a hydrocarbon with carbon-carbon double bonds). Ethylene i ...
with HCl: :H2C=CH2 + HCl → CH3CH2Cl In
oxychlorination In organic chemistry, oxychlorination is a process for making C-Cl bonds. In contrast with direct use of Cl2, oxychlorination uses hydrogen chloride in combination with oxygen.{{Ullmann, author=M. Rossberg , display-authors=et al., title=Chlorinated ...
, hydrogen chloride instead of the more expensive chlorine for the same purpose: :CH2=CH2 + 2 HCl + O2 → ClCH2CH2Cl + H2O. Secondary and tertiary alcohols react with hydrogen chloride to give the corresponding chlorides. In the laboratory, the related reaction involving
zinc chloride Zinc chloride is the name of inorganic chemical compounds with the formula ZnCl2 and its hydrates. Zinc chlorides, of which nine crystalline forms are known, are colorless or white, and are highly soluble in water. This salt is hygroscopic and ev ...
in concentrated
hydrochloric acid Hydrochloric acid, also known as muriatic acid, is an aqueous solution of hydrogen chloride. It is a colorless solution with a distinctive pungent smell. It is classified as a strong acid Acid strength is the tendency of an acid, symbol ...
: : + HCl -> ce\Delta] \overset + H2O Called the Lucas reagent, this mixture was once used in
qualitative organic analysis Analytical chemistry studies and uses instruments and methods to separate, identify, and quantify matter. In practice, separation, identification or quantification may constitute the entire analysis or be combined with another method. Separati ...
for classifying alcohols.


Other chlorinating agents

Alkyl chlorides are most easily prepared by treating alcohols with thionyl chloride (SOCl2) or
phosphorus pentachloride Phosphorus pentachloride is the chemical compound with the formula PCl5. It is one of the most important phosphorus chlorides, others being PCl3 and POCl3. PCl5 finds use as a chlorinating reagent. It is a colourless, water-sensitive and moist ...
(PCl5), but also commonly with sulfuryl chloride (SO2Cl2) and
phosphorus trichloride Phosphorus trichloride is an inorganic compound with the chemical formula PCl3. A colorless liquid when pure, it is an important industrial chemical, being used for the manufacture of phosphites and other organophosphorus compounds. It is toxic a ...
(PCl3): :ROH + SOCl2 → RCl + SO2 + HCl :3 ROH + PCl3 → 3 RCl + H3PO3 :ROH + PCl5 → RCl + POCl3 + HCl In the laboratory, thionyl chloride is especially convenient, because the byproducts are gaseous. Alternatively, the Appel reaction can be used: :


Reactions

Alkyl chlorides are versatile building blocks in organic chemistry. While alkyl bromides and iodides are more reactive, alkyl chlorides tend to be less expensive and more readily available. Alkyl chlorides readily undergo attack by nucleophiles. Heating alkyl halides with
sodium hydroxide Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly caustic base and alkali ...
or
water Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ...
gives alcohols. Reaction with
alkoxide In chemistry, an alkoxide is the conjugate base of an alcohol and therefore consists of an organic group bonded to a negatively charged oxygen atom. They are written as , where R is the organic substituent. Alkoxides are strong bases and, whe ...
s or
aryloxide In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of one or more hydroxyl groups (— O H) bonded directly to an aromatic hydrocarbon group. The simplest is phenol, . Phenolic compounds are c ...
s give
ether In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again be c ...
s in the Williamson ether synthesis; reaction with
thiol In organic chemistry, a thiol (; ), or thiol derivative, is any organosulfur compound of the form , where R represents an alkyl or other organic substituent. The functional group itself is referred to as either a thiol group or a sulfhydryl gro ...
s give thioethers. Alkyl chlorides readily react with
amine In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituen ...
s to give substituted
amine In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituen ...
s. Alkyl chlorides are substituted by softer halides such as the iodide in the Finkelstein reaction. Reaction with other pseudohalides such as
azide In chemistry, azide is a linear, polyatomic anion with the formula and structure . It is the conjugate base of hydrazoic acid . Organic azides are organic compounds with the formula , containing the azide functional group. The dominant applic ...
,
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 ...
, and thiocyanate are possible as well. In the presence of a strong base, alkyl chlorides undergo dehydrohalogenation to give
alkene In organic chemistry, an alkene is a hydrocarbon containing a carbon–carbon double bond. Alkene is often used as synonym of olefin, that is, any hydrocarbon containing one or more double bonds.H. Stephen Stoker (2015): General, Organic, an ...
s or
alkyne \ce \ce Acetylene \ce \ce \ce Propyne \ce \ce \ce \ce 1-Butyne In organic chemistry, an alkyne is an unsaturated hydrocarbon containing at least one carbon—carbon triple bond. The simplest acyclic alkynes with only one triple bond and n ...
s. Alkyl chlorides react with
magnesium Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ta ...
to give
Grignard reagent A Grignard reagent or Grignard compound is a chemical compound with the general formula , where X is a halogen and R is an organic group, normally an alkyl or aryl. Two typical examples are methylmagnesium chloride and phenylmagnesium bromide ...
s, transforming an
electrophilic In chemistry, an electrophile is a chemical species that forms bonds with nucleophiles by accepting an electron pair. Because electrophiles accept electrons, they are Lewis acids. Most electrophiles are positively charged, have an atom that carri ...
compound into a nucleophilic compound. The Wurtz reaction reductively couples two alkyl halides to couple with
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 iso ...
.


Applications


Vinyl chloride

The largest application of organochlorine chemistry is the production of
vinyl chloride Vinyl chloride is an organochloride with the formula H2C=CHCl. It is also called vinyl chloride monomer (VCM) or chloroethene. This colorless compound is an important industrial chemical chiefly used to produce the polymer polyvinyl chloride (PVC ...
. The annual production in 1985 was around 13 million tons, almost all of which was converted into polyvinylchloride (PVC).


Chloromethanes

Most low molecular weight chlorinated hydrocarbons such as
chloroform Chloroform, or trichloromethane, is an organic compound with chemical formula, formula Carbon, CHydrogen, HChlorine, Cl3 and a common organic solvent. It is a colorless, strong-smelling, dense liquid produced on a large scale as a precursor to ...
,
dichloromethane Dichloromethane (DCM or methylene chloride, methylene bichloride) is an organochlorine compound with the formula . This colorless, volatile liquid with a chloroform-like, sweet odour is widely used as a solvent. Although it is not miscible with ...
, dichloroethene, and
trichloroethane Trichloroethane (CHCl) may refer to either of two isomeric chemical compounds: * 1,1,1-Trichloroethane (methyl chloroform, CClCH) * 1,1,2-Trichloroethane 1,1,2-Trichloroethane, or 1,1,2-TCA, is an organochloride solvent with the molecular formula ...
are useful solvents. These solvents tend to be relatively non-polar; they are therefore immiscible with water and effective in cleaning applications such as
degreasing Degreasing, often called defatting or fat trimming, is the removal of fatty acids from an object. In culinary science, degreasing is done with the intention of reducing the fat content of a meal. Degreasing food Degreasing is often used by diete ...
and dry cleaning. Several billion kilograms of chlorinated methanes are produced annually, mainly by chlorination of methane: :CH4 + x Cl2 → CH4−xClx + x HCl The most important is dichloromethane, which is mainly used as a solvent. Chloromethane is a precursor to chlorosilanes and
silicone A silicone or polysiloxane is a polymer made up of siloxane (−R2Si−O−SiR2−, where R = organic group). They are typically colorless oils or rubber-like substances. Silicones are used in sealants, adhesives, lubricants, medicine, cooking ...
s. Historically significant, but smaller in scale is chloroform, mainly a precursor to chlorodifluoromethane (CHClF2) and
tetrafluoroethene Tetrafluoroethylene (TFE) is a fluorocarbon with the chemical formula C2 F4. It is the simplest perfluorinated alkene. This gaseous species is used primarily in the industrial preparation of fluoropolymers. Properties Tetrafluoroethylene is a c ...
which is used in the manufacture of Teflon.


Pesticides

The two main groups of organochlorine insecticides are the
DDT Dichlorodiphenyltrichloroethane, commonly known as DDT, is a colorless, tasteless, and almost odorless crystalline chemical compound, an organochloride. Originally developed as an insecticide, it became infamous for its environmental impacts. ...
-type compounds and the chlorinated
alicyclic In organic chemistry, an alicyclic compound contains one or more all-carbon rings which may be either saturated or unsaturated, but do not have aromatic character. Alicyclic compounds may have one or more aliphatic side chains attached. The ...
s. Their mechanism of action differs slightly. *The DDT like compounds work on the
peripheral nervous system The peripheral nervous system (PNS) is one of two components that make up the nervous system of bilateral animals, with the other part being the central nervous system (CNS). The PNS consists of nerves and ganglia, which lie outside the brain ...
. At the axon's
sodium channel Sodium channels are integral membrane proteins that form ion channels, conducting sodium ions (Na+) through a cell's membrane. They belong to the superfamily of cation channels and can be classified according to the trigger that opens the channel ...
, they prevent gate closure after activation and membrane depolarization. Sodium ions leak through the nerve membrane and create a destabilizing negative "afterpotential" with hyperexcitability of the nerve. This leakage causes repeated discharges in the neuron either spontaneously or after a single stimulus. *Chlorinated cyclodienes include aldrin,
dieldrin Dieldrin is an organochloride originally produced in 1948 by J. Hyman & Co, Denver, as an insecticide. Dieldrin is closely related to aldrin, which reacts further to form dieldrin. Aldrin is not toxic to insects; it is oxidized in the insect to fo ...
, endrin, heptachlor, chlordane and
endosulfan Endosulfan is an off-patent organochlorine insecticide and acaricide that is being phased out globally. It became a highly controversial agrichemical due to its acute toxicity, potential for bioaccumulation, and role as an endocrine disruptor. ...
. A 2- to 8-hour exposure leads to depressed
central nervous system The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all par ...
(CNS) activity, followed by hyperexcitability, tremors, and then seizures. The mechanism of action is the insecticide binding at the GABAA site in the gamma-aminobutyric acid (GABA) chloride ionophore complex, which inhibits chloride flow into the nerve. *Other examples include
dicofol Dicofol is an organochlorine pesticide that is chemically related to DDT. Dicofol is a miticide that is very effective against spider mite. One of the intermediates used in its production is DDT. This has caused criticism by many environmentalis ...
, mirex,
kepone Chlordecone, better known in the United States under the brand name Kepone, is an organochlorine compound and a colourless solid. It is an obsolete insecticide, now prohibited in the western world, but only after many thousands of tonnes had bee ...
, and
pentachlorophenol Pentachlorophenol (PCP) is an organochlorine compound used as a pesticide and a disinfectant. First produced in the 1930s, it is marketed under many trade names. It can be found as pure PCP, or as the sodium salt of PCP, the latter of which diss ...
. These can be either
hydrophilic A hydrophile is a molecule or other molecular entity that is attracted to water molecules and tends to be dissolved by water.Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon'' Oxford: Clarendon Press. In contrast, hydrophobes are no ...
or
hydrophobic In chemistry, hydrophobicity is the physical property of a molecule that is seemingly repelled from a mass of water (known as a hydrophobe). In contrast, hydrophiles are attracted to water. Hydrophobic molecules tend to be nonpolar and, th ...
, depending on their molecular structure.Robert L. Metcalf "Insect Control" in ''Ullmann's Encyclopedia of Industrial Chemistry'' Wiley-VCH, Wienheim, 2002.


Insulators

Polychlorinated biphenyl Polychlorinated biphenyls (PCBs) are highly carcinogenic chemical compounds, formerly used in industrial and consumer products, whose production was banned in the United States by the Toxic Substances Control Act in 1979 and internationally by t ...
s (PCBs) were once commonly used electrical insulators and heat transfer agents. Their use has generally been phased out due to health concerns. PCBs were replaced by polybrominated diphenyl ethers (PBDEs), which bring similar toxicity and
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 ...
concerns.


Toxicity

Some types of organochlorides have significant toxicity to plants or animals, including humans. Dioxins, produced when organic matter is burned in the presence of chlorine, are persistent organic pollutants which pose dangers when they are released into the environment, as are some insecticides (such as
DDT Dichlorodiphenyltrichloroethane, commonly known as DDT, is a colorless, tasteless, and almost odorless crystalline chemical compound, an organochloride. Originally developed as an insecticide, it became infamous for its environmental impacts. ...
). For example, DDT, which was widely used to control insects in the mid-20th century, also accumulates in food chains, as do its metabolites DDE and DDD, and causes reproductive problems (e.g., eggshell thinning) in certain bird species. DDT also posed further issues to the environment as it is extremely mobile, traces even being found in Antarctica despite the chemical never being used there. Some organochlorine compounds, such as
sulfur mustard 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 ...
s,
nitrogen mustard Nitrogen mustards are cytotoxic organic compounds with the chloroethylamine (Cl(CH2)2NR2) functional group. Although originally produced as chemical warfare agents, they were the first chemotherapeutic agents for treatment of cancer. Nitrogen m ...
s, and
Lewisite Lewisite (L) (A-243) is an organoarsenic compound. It was once manufactured in the U.S., Japan, Germany and the Soviet Union for use as a Chemical warfare, chemical weapon, acting as a vesicant (blister agent) and lung irritant. Although the substa ...
, are even used as chemical weapons due to their toxicity. However, the presence of chlorine in an organic compound does not ensure toxicity. Some organochlorides are considered safe enough for consumption in foods and medicines. For example, peas and broad beans contain the natural chlorinated plant hormone
4-chloroindole-3-acetic acid 4-Chloroindole-3-acetic acid (4-Cl-IAA) is an organic compound that functions as a plant hormone. Synopsis It is a member of the class of compounds known as auxins and a chlorinated analogue of the more common indole-3-acetic acid (IAA) auxin. 4- ...
(4-Cl-IAA); and the sweetener
sucralose Sucralose is an artificial sweetener and sugar substitute. The majority of ingested sucralose is not broken down by the body, so it is noncaloric. In the European Union, it is also known under the E number E955. It is produced by chlorination of ...
(Splenda) is widely used in diet products. , at least 165 organochlorides had been approved worldwide for use as pharmaceutical drugs, including the natural antibiotic
vancomycin Vancomycin is a glycopeptide antibiotic medication used to treat a number of bacterial infections. It is recommended intravenously as a treatment for complicated skin infections, bloodstream infections, endocarditis, bone and joint infections, ...
, the antihistamine
loratadine Loratadine, sold under the brand name Claritin among others, is a medication used to treat allergies. This includes allergic rhinitis (hay fever) and hives. It is also available in combination with pseudoephedrine, a decongestant, known as lora ...
(Claritin), the antidepressant
sertraline Sertraline, sold under the brand name Zoloft among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. The efficacy of sertraline for depression is similar to that of other antidepressants, and the differe ...
(Zoloft), the anti-epileptic
lamotrigine Lamotrigine, sold under the brand name Lamictal among others, is a medication used to treat epilepsy and stabilize mood in bipolar disorder. For epilepsy, this includes focal seizures, tonic-clonic seizures, and seizures in Lennox-Gastaut synd ...
(Lamictal), and the inhalation anesthetic
isoflurane Isoflurane, sold under the brand name Forane among others, is a general anesthetic. It can be used to start or maintain anesthesia; however, other medications are often used to start anesthesia rather than isoflurane, due to airway irritation w ...
. Rachel Carson brought the issue of DDT pesticide toxicity to public awareness with her 1962 book '' Silent Spring''. While many countries have phased out the use of some types of organochlorides such as the US ban on DDT, persistent DDT, PCBs, and other organochloride residues continue to be found in humans and mammals across the planet many years after production and use have been limited. In
Arctic The Arctic ( or ) is a polar regions of Earth, polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenla ...
areas, particularly high levels are found in
marine mammal Marine mammals are aquatic mammals that rely on the ocean and other marine ecosystems for their existence. They include animals such as seals, whales, manatees, sea otters and polar bears. They are an informal group, unified only by their reli ...
s. These chemicals concentrate in mammals, and are even found in human breast milk. In some species of marine mammals, particularly those that produce milk with a high fat content, males typically have far higher levels, as females reduce their concentration by transfer to their offspring through lactation.''Marine Mammal Medicine'', 2001, Dierauf & Gulland


See also

*
Organic halide Halocarbon compounds are chemicals in which one or more carbon atoms are linked by covalent bonds with one or more halogen atoms ( fluorine, chlorine, bromine or iodine – ) resulting in the formation of organofluorine compounds, organoch ...


References


External links


"Formation of Chlorinated Hydrocarbons in Weathering Plant Material" article at SLAC website
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