![PCDD general structure](https://upload.wikimedia.org/wikipedia/commons/d/d8/PCDD_general_structure.png)
Polychlorinated dibenzodioxins (PCDDs), or simply dioxins, are a group of long-lived
polyhalogenated 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 ...
s that are primarily anthropogenic, and contribute toxic,
persistent organic pollution in the environment.
They are commonly but inaccurately referred to as dioxins for simplicity, because every PCDD
molecule
A molecule is a group of two or more atoms held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions which satisfy this criterion. In quantum physics, organic chemistry, and bioch ...
contains a
dibenzo-1,4-dioxin
Dibenzo-1,4-dioxin, also dibenzodioxin or dibenzo-''p''-dioxin (dibenzo-''para''-dioxin), is a polycyclic heterocyclic organic compound in which two benzene rings are connected by a 1,4-dioxin ring. Its molecular formula is C12H8O2. The two ox ...
skeletal structure, with
1,4-dioxin
1,4-Dioxin (also referred as dioxin or ''p''-dioxin) is a heterocyclic, organic, non-aromatic compound with the chemical formula CHO. There is an isomeric form of 1,4-dioxin, 1,2-dioxin (or ''o''-dioxin). 1,2-Dioxin is very unstable due to its ...
as the central
ring
Ring may refer to:
* Ring (jewellery), a round band, usually made of metal, worn as ornamental jewelry
* To make a sound with a bell, and the sound made by a bell
:(hence) to initiate a telephone connection
Arts, entertainment and media Film and ...
. Members of the PCDD family
bioaccumulate
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 ...
in humans and
wildlife
Wildlife refers to domestication, undomesticated animal species (biology), species, but has come to include all organisms that grow or live wilderness, wild in an area without being species, introduced by humans. Wildlife was also synonymous ...
because of their
lipophilic
Lipophilicity (from Greek λίπος "fat" and φίλος "friendly"), refers to the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene. Such non-polar solvents are themselves lipop ...
properties, and may cause developmental disturbances and
cancer
Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal b ...
.
Because dioxins can persist in the environment for more than 100 years, the majority of PCDD pollution today is not the result of recent emissions, but the cumulative result of synthetic processes undertaken since the beginning of the 20th century, including
organochloride
An organochloride, organochlorine compound, chlorocarbon, or chlorinated hydrocarbon is an organic compound containing at least one covalent bond, covalently bonded atom of chlorine. The chloroalkane class (alkanes with one or more hydrogens subst ...
-related manufacturing, incineration of chlorine-containing substances such as
polyvinyl chloride (PVC), and
chlorine bleaching of paper.
Forest fires and volcanic eruptions have also been cited as an airborne source, although their contribution to the current levels of PCDD accumulation are minor in comparison. Incidents of dioxin poisoning resulting from industrial emissions and accidents were first recorded as early as the mid 19th century during the
Industrial Revolution
The Industrial Revolution was the transition to new manufacturing processes in Great Britain, continental Europe, and the United States, that occurred during the period from around 1760 to about 1820–1840. This transition included going f ...
.
The word "dioxins" may also refer to other similarly acting chlorinated compounds (see
Dioxins and dioxin-like compounds
Dioxins and dioxin-like compounds (DLCs) are a group of chemical compounds that are persistent organic pollutants (POPs) in the environment. They are mostly by-products of burning or various industrial processes - or, in case of dioxin-like PCBs an ...
).
Chemical structure of dibenzo-1,4-dioxins
![Dibenzo-p-dioxin-numbering-2D-skeletal](https://upload.wikimedia.org/wikipedia/commons/8/8e/Dibenzo-p-dioxin-numbering-2D-skeletal.png)
The structure of
dibenzo-1,4-dioxin
Dibenzo-1,4-dioxin, also dibenzodioxin or dibenzo-''p''-dioxin (dibenzo-''para''-dioxin), is a polycyclic heterocyclic organic compound in which two benzene rings are connected by a 1,4-dioxin ring. Its molecular formula is C12H8O2. The two ox ...
consists of two
benzene ring
Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, ...
s joined by two oxygen bridges. This makes the compound an
aromatic
In chemistry, aromaticity is a chemical property of cyclic ( ring-shaped), ''typically'' planar (flat) molecular structures with pi bonds in resonance (those containing delocalized electrons) that gives increased stability compared to satur ...
di
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 ...
. The name dioxin formally refers to the central dioxygenated ring, which is stabilized by the two flanking
benzene ring
Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, ...
s.
In PCDDs, chlorine atoms are attached to this structure at any of 8 different places on the molecule, at positions 1–4 and 6–9. There are 75 different PCDD
congeners (that is, related dioxin compounds).
The toxicity of PCDDs depends on the number and positions of the chlorine atoms. Congeners that have chlorine in the 2, 3, 7, and 8 positions have been found to be significantly toxic. In fact, 7 congeners have chlorine atoms in the relevant positions which were considered toxic by the World Health Organization toxic equivalent (WHO-TEQ) scheme.
Historical perspective
Low concentrations of dioxins existed in nature prior to
industrialization
Industrialisation ( alternatively spelled industrialization) is the period of social and economic change that transforms a human group from an agrarian society into an industrial society. This involves an extensive re-organisation of an econo ...
as a result of natural combustion and geological processes. Dioxins were first unintentionally produced as by-products from 1848 onwards as
Leblanc process
The Leblanc process (pronounced leh-blaank) was an early industrial process for making ''soda ash'' (sodium carbonate) used throughout the 19th century, named after its inventor, Nicolas Leblanc. It involved two stages: making sodium sulfate from ...
plants started operating in Germany.
The first intentional synthesis of chlorinated dibenzodioxin was in 1872. Today, concentrations of dioxins are found in all humans, with higher levels commonly found in persons living in more industrialized countries. The most toxic dioxin,
2,3,7,8-tetrachlorodibenzodioxin
2,3,7,8-Tetrachlorodibenzo-''p-''dioxin (TCDD) is a polychlorinated dibenzo''-p-''dioxin (sometimes shortened, though inaccurately, to simply 'dioxin')Tuomisto, Jouko (2019) Dioxins and dioxin-like compounds: toxicity in humans and animals, s ...
(TCDD), became well known as a contaminant of
Agent Orange
Agent Orange is a chemical herbicide and defoliant, one of the "tactical use" Rainbow Herbicides. It was used by the U.S. military as part of its herbicidal warfare program, Operation Ranch Hand, during the Vietnam War from 1961 to 1971. It ...
, a herbicide used in the
Malayan Emergency
The Malayan Emergency, also known as the Anti–British National Liberation War was a guerrilla war fought in British Malaya between communist pro-independence fighters of the Malayan National Liberation Army (MNLA) and the military forces o ...
and the
Vietnam War
The Vietnam War (also known by #Names, other names) was a conflict in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. It was the second of the Indochina Wars and was officially fought between North Vie ...
.
Later, dioxins were found in
Times Beach
Times Beach is a ghost town in St. Louis County, Missouri, United States, southwest of St. Louis and east of Eureka. Once home to more than two thousand people, the town was completely evacuated early in 1983 due to TCDD—also known as dioxin ...
,
Missouri
Missouri is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. Ranking List of U.S. states and territories by area, 21st in land area, it is bordered by eight states (tied for the most with Tennessee ...
and
Love Canal
Love Canal is a neighborhood in Niagara Falls, New York, United States, infamous as the location of a landfill that became the site of an enormous environmental disaster in the 1970s. Decades of dumping toxic chemicals harmed the health of hund ...
,
New York
New York most commonly refers to:
* New York City, the most populous city in the United States, located in the state of New York
* New York (state), a state in the northeastern United States
New York may also refer to:
Film and television
* '' ...
and
Seveso
Seveso (; lmo, label= Lombard, Séves ) is a town and ''comune'' in the Province of Monza and Brianza, in the Region of Lombardy. The economy of the town has traditionally been based on the furniture industry.
Its name comes from the river of ...
,
Italy
Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical re ...
. More recently, dioxins have been in the news with the poisoning of President
Viktor Yushchenko
Viktor Andriyovych Yushchenko ( uk, Віктор Андрійович Ющенко, ; born 23 February 1954) is a Ukrainian politician who was the third president of Ukraine from 23 January 2005 to 25 February 2010.
As an informal leader of th ...
of
Ukraine
Ukraine ( uk, Україна, Ukraïna, ) is a country in Eastern Europe. It is the second-largest European country after Russia, which it borders to the east and northeast. Ukraine covers approximately . Prior to the ongoing Russian inv ...
in 2004,
the Naples Mozzarella Crisis,
the
2008 Irish pork crisis
The Irish pork crisis of 2008 was a dioxin contamination incident in Ireland that led to an international recall of pork products from Ireland produced between September and early December of that year. It was disclosed in early December 2008 ...
, and the
German feed incident of 2010.
Sources of dioxins
The
United States Environmental Protection Agency
The Environmental Protection Agency (EPA) is an independent executive agency of the United States federal government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it be ...
inventory of sources of dioxin-like compounds is possibly the most comprehensive review of the sources and releases of dioxins,
[ EPA/600/P-03/002f, Final Report] but other countries now have substantial research as well.
![PCDD sediment core](https://upload.wikimedia.org/wikipedia/commons/d/d2/PCDD_sediment_core.svg)
Occupational exposure is an issue for some in the
chemical industries
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 elements by physical separation methods, i.e., wit ...
, historically for those making
chlorophenol
A chlorophenol is any organochloride of phenol that contains one or more covalently bonded chlorine atoms. There are five basic types of chlorophenols (mono- to pentachlorophenol) and 19 different chlorophenols in total when positional isomerism is ...
s or
chlorophenoxy acid herbicides or in the application of chemicals, notably herbicides. In many developed nations there are now emissions regulations which have dramatically decreased the emissions
and thus alleviated some concerns, although the lack of continuous sampling of dioxin emissions causes concern about the understatement of emissions. In
Belgium
Belgium, ; french: Belgique ; german: Belgien officially the Kingdom of Belgium, is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to th ...
, through the introduction of a process called
AMESA, continuous sampling showed that periodic sampling understated emissions by a factor of 30 to 50 times. Few facilities have continuous sampling.
Dioxins are produced in small concentrations when organic material is
burned in the presence 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 ...
, whether the chlorine is present as
chloride
The chloride ion is the anion (negatively charged ion) Cl−. It is formed when the element chlorine (a halogen) gains an electron or when a compound such as hydrogen chloride is dissolved in water or other polar solvents. Chloride salts ...
ion
An ion () is an atom or molecule with a net electrical charge.
The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by conve ...
s or as
organochlorine compound
An organochloride, organochlorine compound, chlorocarbon, or chlorinated hydrocarbon is an organic compound containing at least one covalent bond, covalently bonded atom of chlorine. The chloroalkane class (alkanes with one or more hydrogens subst ...
s, so they are widely produced in many contexts. According to the most recent US EPA data, the major sources of dioxins are broadly in the following types:
*Combustion sources, e.g.
municipal waste
Municipal solid waste (MSW), commonly known as trash or garbage in the United States and rubbish in Britain, is a waste type consisting of everyday items that are discarded by the public. "Garbage" can also refer specifically to food waste, ...
or
medical waste
Biomedical waste or hospital waste is any kind of waste containing infectious (or potentially infectious) materials. It may also include waste associated with the generation of biomedical waste that visually appears to be of medical or laboratory ...
incinerator
Incineration is a waste treatment process that involves the combustion of substances contained in waste materials. Industrial plants for waste incineration are commonly referred to as waste-to-energy facilities. Incineration and other high ...
s and private backyard barrel burning
*
Metal smelting
Smelting is a process of applying heat to ore, to extract a base metal. It is a form of extractive metallurgy. It is used to extract many metals from their ores, including Silver mining#Ore processing, silver, iron-making, iron, copper extracti ...
*Refining and process sources
*Chemical manufacturing sources
*Natural sources
*Environmental reservoirs
When first carried out in 1987, the original US EPA inventory of dioxin sources revealed that incineration represented more than 80% of known dioxin sources. As a result, US EPA implemented new emissions requirements. These regulations succeeded in reducing dioxin stack emissions from incinerators. Incineration of
municipal solid waste
Municipal solid waste (MSW), commonly known as trash or garbage in the United States and rubbish in Britain, is a waste type consisting of everyday items that are discarded by the public. "Garbage" can also refer specifically to food waste, ...
,
medical waste
Biomedical waste or hospital waste is any kind of waste containing infectious (or potentially infectious) materials. It may also include waste associated with the generation of biomedical waste that visually appears to be of medical or laboratory ...
,
sewage sludge
Sewage sludge is the residual, semi-solid material that is produced as a by-product during sewage treatment of industrial or municipal wastewater. The term "septage" also refers to sludge from simple wastewater treatment but is connected to si ...
, and
hazardous waste
Hazardous waste is waste that has substantial or potential threats to public health or the environment. Hazardous waste is a type of dangerous goods. They usually have one or more of the following hazardous traits: ignitability, reactivity, co ...
together now produce less than 3% of all dioxin emissions. Since 1987, however, backyard barrel burning has showed almost no decrease, and is now the largest source of dioxin emissions, producing about one third of the total output.
In incineration, dioxins can also reform or form ''de novo'' in the
atmosphere
An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A s ...
above the stack as the exhaust gases cool through a temperature window of 600 to 200 °C. The most common method of reducing the quantity of dioxins reforming or forming ''de novo'' is through rapid (30 millisecond)
quenching
In materials science, quenching is the rapid cooling of a workpiece in water, oil, polymer, air, or other fluids to obtain certain material properties. A type of heat treating, quenching prevents undesired low-temperature processes, such as pha ...
of the exhaust gases through that 400 °C window.
Incinerator emissions of dioxins have been reduced by over 90% as a result of new emissions control requirements. Incineration in developed countries is now a very minor contributor to dioxin emissions.
Dioxins are also generated in reactions that do not involve burning — such as
chlorine bleaching fibers for
paper
Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, rags, grasses or other vegetable sources in water, draining the water through fine mesh leaving the fibre evenly distributed ...
or textiles, and in the manufacture of chlorinated phenols, particularly when reaction temperature is not well controlled. Compounds involved include the wood preservative
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 ...
, and also
herbicide
Herbicides (, ), also commonly known as weedkillers, are substances used to control undesired plants, also known as weeds.EPA. February 201Pesticides Industry. Sales and Usage 2006 and 2007: Market Estimates. Summary in press releasMain page fo ...
s such as
2,4-dichlorophenoxyacetic acid (or 2,4-D) and
2,4,5-trichlorophenoxyacetic acid (2,4,5-T). Higher levels of chlorination require higher reaction temperatures and greater dioxin production. Dioxins may also be formed during the
photochemical
Photochemistry is the branch of chemistry concerned with the chemical effects of light. Generally, this term is used to describe a chemical reaction caused by absorption of ultraviolet (wavelength from 100 to 400 nm), visible light (400–7 ...
breakdown of the common antimicrobial compound
triclosan
Triclosan (sometimes abbreviated as TCS) is an antibiotic, antibacterial and fungus, antifungal agent present in some consumer products, including toothpaste, soaps, detergents, toys, and surgical cleaning treatments. It is similar in its uses a ...
.
Sources of human intake
![Dioxin chart](https://upload.wikimedia.org/wikipedia/commons/f/f9/Dioxin_chart.png)
Tolerable daily, monthly or annual intakes have been set by the
World Health Organization
The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level of h ...
and a number of governments. Dioxins enter the general population almost exclusively from ingestion of food, specifically through the consumption of fish, meat, and dairy products since dioxins are fat-soluble and readily climb the
food chain
A food chain is a linear network of links in a food web starting from producer organisms (such as grass or algae which produce their own food via photosynthesis) and ending at an apex predator species (like grizzly bears or killer whales), det ...
.
Children are passed substantial body burdens by their mothers, and
breastfeeding
Breastfeeding, or nursing, is the process by which human breast milk is fed to a child. Breast milk may be from the breast, or may be expressed by hand or pumped and fed to the infant. The World Health Organization (WHO) recommends that br ...
increases the child's body burden.
Dioxin exposure can also occur from contact with Pentachlorophenol (Penta) treated lumber as Pentachlorophenol often contains dioxins as a contaminant. Children's daily intakes during breast feeding are often many times above the intakes of adults based on body weight. This is why the WHO consultation group assessed the tolerable intake so as to prevent a woman from accumulating harmful body burdens before her first pregnancy.
Breast fed children usually still have higher dioxin body burdens than non breast fed children. The
WHO
Who or WHO may refer to:
* Who (pronoun), an interrogative or relative pronoun
* Who?, one of the Five Ws in journalism
* World Health Organization
Arts and entertainment Fictional characters
* Who, a creature in the Dr. Seuss book '' Horton He ...
still recommends breast feeding for its other benefits. In many countries dioxins in breast milk have decreased by even 90% during the two last decades.
Dioxins are present in
cigarette smoke. Dioxin in cigarette smoke was noted as "understudied" by the US EPA in its "Re-Evaluating Dioxin" (1995). In that same document, the US EPA acknowledged that dioxin in cigarettes is "anthropogenic" (man-made, "not likely in nature").
Metabolism
Dioxins are absorbed primarily through dietary intake of fat, as this is where they accumulate in animals and humans. In humans, the highly chlorinated dioxins are stored in fatty tissues and are neither readily metabolized nor excreted. The estimated elimination
half-life
Half-life (symbol ) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable ato ...
for highly chlorinated dioxins (4–8 chlorine atoms) in humans ranges from 4.9 to 13.1 years.
The persistence of a particular dioxin
congener in an animal is thought to be a consequence of its structure. Dioxins with no lateral (2, 3, 7, and 8) chlorines, which thus contain hydrogen atoms on adjacent pairs of carbons, can more readily be oxidized by
cytochromes P450. The oxidized dioxins can then be more readily excreted rather than stored for a long time.
Toxicity
2,3,7,8-Tetrachlorodibenzodioxin
2,3,7,8-Tetrachlorodibenzo-''p-''dioxin (TCDD) is a polychlorinated dibenzo''-p-''dioxin (sometimes shortened, though inaccurately, to simply 'dioxin')Tuomisto, Jouko (2019) Dioxins and dioxin-like compounds: toxicity in humans and animals, s ...
(TCDD) is considered the most toxic of the
congeners (for the mechanism of action, see
2,3,7,8-Tetrachlorodibenzodioxin
2,3,7,8-Tetrachlorodibenzo-''p-''dioxin (TCDD) is a polychlorinated dibenzo''-p-''dioxin (sometimes shortened, though inaccurately, to simply 'dioxin')Tuomisto, Jouko (2019) Dioxins and dioxin-like compounds: toxicity in humans and animals, s ...
and
Aryl hydrocarbon receptor
The aryl hydrocarbon receptor (also known as AhR, AHR, ahr, ahR, or dioxin receptor) is a protein that in humans is encoded by the AHR gene. The aryl hydrocarbon receptor is a transcription factor that regulates gene expression. It was originall ...
). Other dioxin congeners including PCDFs and PCBs with dioxin-like toxicity, are given a toxicity rating from 0 to 1, where TCDD = 1 (see
Dioxins and dioxin-like compounds
Dioxins and dioxin-like compounds (DLCs) are a group of chemical compounds that are persistent organic pollutants (POPs) in the environment. They are mostly by-products of burning or various industrial processes - or, in case of dioxin-like PCBs an ...
). This toxicity rating is called the Toxic Equivalence Factor concept, or
TEF. TEFs are consensus values and, because of the strong species dependence for toxicity, are listed separately for mammals, fish, and birds. TEFs for mammalian species are generally applicable to human risk calculations. The TEFs have been developed from detailed assessment of literature data to facilitate both risk assessment and regulatory control.
Many other compounds may also have dioxin-like properties, particularly non-ortho
PCBs
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 ...
, one of which has a TEF as high as 0.1.
The total dioxin toxic equivalence (TEQ) value expresses the toxicity as if the mixture were pure TCDD. The TEQ approach and current TEFs have been adopted internationally as the most appropriate way to estimate the potential health risks of mixture of dioxins. Recent data suggest that this type of simple scaling factor may not be the most appropriate treatment for complex mixtures of dioxins; both transfer from the source and absorption and elimination vary among different congeners, and the TEF value is not able to accurately reflect this.
Dioxins and other
persistent organic pollutant
Persistent organic pollutants (POPs), sometimes known as "forever chemicals", are organic compounds that are resistant to environmental degradation through chemical, biological, and photolytic processes. They are toxic chemicals that adversely ...
s (POPs) are subject to the
Stockholm Convention
Stockholm Convention on Persistent Organic Pollutants is an international environmental treaty, signed on 22 May 2001 in Stockholm and effective from 17 May 2004, that aims to eliminate or restrict the production and use of persistent organic ...
. The
treaty
A treaty is a formal, legally binding written agreement between actors in international law. It is usually made by and between sovereign states, but can include international organizations
An international organization or international o ...
obliges signatories to take measures to eliminate where possible, and minimize where not possible to eliminate, all sources of dioxin.
Health effects in humans
![Chloracne-in-herbicide-worker](https://upload.wikimedia.org/wikipedia/commons/5/5a/Chloracne-in-herbicide-worker.png)
Dioxins build up primarily in fatty tissues over time (
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 ...
), so even small exposures may eventually reach dangerous levels. In 1994, the US EPA reported that dioxins are a probable
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 substan ...
, but noted that non-cancer effects (reproduction and sexual development, immune system) may pose a greater threat to human health.
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 ...
, the most toxic of the dibenzodioxins, is classified as a Group 1 carcinogen by the
International Agency for Research on Cancer
The International Agency for Research on Cancer (IARC; french: Centre International de Recherche sur le Cancer, CIRC) is an intergovernmental agency forming part of the World Health Organization of the United Nations.
Its role is to conduct and ...
(IARC). TCDD has a half-life of approximately 8 years in humans, although at high concentrations, the elimination rate is enhanced by metabolism.
The health effects of dioxins are mediated by their action on a cellular receptor, the
aryl hydrocarbon receptor
The aryl hydrocarbon receptor (also known as AhR, AHR, ahr, ahR, or dioxin receptor) is a protein that in humans is encoded by the AHR gene. The aryl hydrocarbon receptor is a transcription factor that regulates gene expression. It was originall ...
(AhR).
Exposure to high levels of dioxins in humans causes a severe form of persistent
acne
Acne, also known as ''acne vulgaris'', is a long-term Cutaneous condition, skin condition that occurs when Keratinocyte, dead skin cells and Sebum, oil from the skin clog hair follicles. Typical features of the condition include comedo, black ...
, known as
chloracne
Chloracne is an acne-like eruption of blackheads, cysts, and pustules associated with exposure to certain halogenated aromatic compounds, such as chlorinated dioxins and dibenzofurans. The lesions are most frequently found on the cheeks, behind ...
.
High occupational or accidental levels of exposures to dioxins have been shown by epidemiological studies to lead to an increased risk of tumors at all sites. Other effects in humans (at high dose levels) may include:
*Developmental abnormalities in the
enamel of children's
teeth
A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, tear ...
.
*
Central
Central is an adjective usually referring to being in the center of some place or (mathematical) object.
Central may also refer to:
Directions and generalised locations
* Central Africa, a region in the centre of Africa continent, also known as ...
and
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 ...
pathology
*
Thyroid
The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thy ...
disorders
*Damage to the
immune system
The immune system is a network of biological processes that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as cancer cells and objects such as wood splinte ...
s
*
Endometriosis
Endometriosis is a disease of the female reproductive system in which cells similar to those in the endometrium, the layer of tissue that normally covers the inside of the uterus, grow outside the uterus. Most often this is on the ovaries, f ...
*
Diabetes
Diabetes, also known as diabetes mellitus, is a group of metabolic disorders characterized by a high blood sugar level ( hyperglycemia) over a prolonged period of time. Symptoms often include frequent urination, increased thirst and increased ap ...
Recent studies have shown that high exposure to dioxins changes the ratio of male to female births among a population such that more females are born than males.
Dioxins accumulate in food chains in a fashion similar to other chlorinated compounds (
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 ...
). This means that even small concentrations in contaminated water can be concentrated up a food chain to dangerous levels because of the long biological half life and low water solubility of dioxins.
Toxic effects in animals
While it has been difficult to establish specific health effects in humans due to the lack of controlled dose experiments, studies in animals have shown that dioxin causes a wide variety of toxic effects.
[R. Pohjanvirta, J. Tuomisto, Short-term toxicity of 2,3,7,8-tetrachlorodibenzop- dioxin in laboratory animals: effects, mechanisms, and animal models, Pharmacological Reviews 1994: 46: 483–549.] In particular,
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 ...
has been shown to be
teratogenic
Teratology is the study of abnormalities of physiological development in organisms during their life span. It is a sub-discipline in medical genetics which focuses on the classification of congenital abnormalities in dysmorphology. The related t ...
,
mutagenic
In genetics, a mutagen is a physical or chemical agent that permanently changes genetic material, usually DNA, in an organism and thus increases the frequency of mutations above the natural background level. As many mutations can cause cancer in ...
,
carcinogenic
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 substan ...
,
immunotoxic
An immunotoxin is an artificial protein consisting of a targeting portion linked to a toxin. When the protein binds to that cell, it is taken in through endocytosis, and the toxin kills the cell. They are used for the treatment of some kinds of c ...
, and
hepatotoxic
Hepatotoxicity (from ''hepatic toxicity'') implies chemical-driven liver damage. Drug-induced liver injury is a cause of acute and chronic liver disease caused specifically by medications and the most common reason for a drug to be withdrawn fro ...
. Furthermore, alterations in multiple
endocrine
The endocrine system is a messenger system comprising feedback loops of the hormones released by internal glands of an organism directly into the circulatory system, regulating distant target organs. In vertebrates, the hypothalamus is the neu ...
and
growth factor
A growth factor is a naturally occurring substance capable of stimulating cell proliferation, wound healing, and occasionally cellular differentiation. Usually it is a secreted protein or a steroid hormone. Growth factors are important for regu ...
systems have been reported. The most sensitive effects, observed in multiple species, appear to be developmental, including effects on the developing
immune
In biology, immunity is the capability of multicellular organisms to resist harmful microorganisms. Immunity involves both specific and nonspecific components. The nonspecific components act as barriers or eliminators of a wide range of pathogens ...
,
nervous, and
reproductive system
The reproductive system of an organism, also known as the genital system, is the biological system made up of all the anatomical organs involved in sexual reproduction. Many non-living substances such as fluids, hormones, and pheromones are als ...
s.
The most sensitive effects are caused at
body burden
In analytical chemistry, biomonitoring is the measurement of the body burden of toxic chemical compounds, elements, or their metabolites, in biological substances. Often, these measurements are done in blood and urine. Biomonitoring is performe ...
s relatively close to those reported in humans.
Among the animals for which TCDD toxicity has been studied, there is strong evidence for the following effects:
*Birth defects (
teratogenic
Teratology is the study of abnormalities of physiological development in organisms during their life span. It is a sub-discipline in medical genetics which focuses on the classification of congenital abnormalities in dysmorphology. The related t ...
ity)
:In rodents, including rats,
mice,
hamsters and guinea pigs,
birds,
and fish.
*Cancer (including
neoplasms
A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...
in the mammalian lung, oral/nasal cavities,
thyroid
The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thy ...
and
adrenal
The adrenal glands (also known as suprarenal glands) are endocrine glands that produce a variety of hormones including adrenaline and the steroids aldosterone and cortisol. They are found above the kidneys. Each gland has an outer cortex which ...
glands, and liver,
squamous cell
Epithelium or epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. It is a thin, continuous, protective layer of compactly packed cells with a little intercellula ...
carcinoma, and various animal
hepatocarcinomas)
:In rodents
and fish.
*Hepatotoxicity (liver toxicity)
:In rodents,
chickens,
and fish.
*Endocrine disruption
:In rodents
and fish.
*Immunosuppression
:In rodents
and fish.
The LD50 of dioxin also varies wildly between species with the most notable disparity being between the ostensibly similar species of hamster and guinea pig. The oral LD50 for guinea pigs is as low as 0.5 to 2 μg/kg body weight, whereas the oral LD50 for hamsters can be as high as 1 to 5 mg/kg body weight, a difference of as much as thousandfold or more, and even among rat strains there may be thousandfold differences.
[
]
Agent Orange
Agent Orange was the code name for one of the herbicide
Herbicides (, ), also commonly known as weedkillers, are substances used to control undesired plants, also known as weeds.EPA. February 201Pesticides Industry. Sales and Usage 2006 and 2007: Market Estimates. Summary in press releasMain page fo ...
s and defoliant
A defoliant is any herbicidal chemical sprayed or dusted on plants to cause their leaves to fall off. Defoliants are widely used for the selective removal of weeds in managing croplands and lawns. Worldwide use of defoliants, along with the ...
s the U.S. military
The United States Armed Forces are the military forces of the United States. The armed forces consists of six service branches: the Army, Marine Corps, Navy, Air Force, Space Force, and Coast Guard. The president of the United States is the ...
used as part of its herbicidal warfare
Herbicidal warfare is the use of substances primarily designed to destroy the plant-based ecosystem of an area. Although herbicidal warfare use chemical substances, its main purpose is to disrupt agricultural food production and/or to destroy pl ...
program, Operation Ranch Hand
Operation Ranch Hand was a U.S. military operation during the Vietnam War, lasting from 1962 until 1971. Largely inspired by the British use of 2,4,5-T and 2,4-D ( Agent Orange) during the Malayan Emergency in the 1950s, it was part of the ov ...
, during the Vietnam War
The Vietnam War (also known by #Names, other names) was a conflict in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. It was the second of the Indochina Wars and was officially fought between North Vie ...
from 1961 to 1971. It was a mixture of 2,4,5-T and 2,4-D. The 2,4,5-T used was contaminated with 2,3,7,8-tetrachlorodibenzodioxin
2,3,7,8-Tetrachlorodibenzo-''p-''dioxin (TCDD) is a polychlorinated dibenzo''-p-''dioxin (sometimes shortened, though inaccurately, to simply 'dioxin')Tuomisto, Jouko (2019) Dioxins and dioxin-like compounds: toxicity in humans and animals, s ...
(TCDD), an extremely toxic dioxin compound
Dioxins and dioxin-like compounds (DLCs) are a group of chemical compounds that are persistent organic pollutants (POPs) in the environment. They are mostly by-products of burning or various industrial processes - or, in case of dioxin-like PCBs ...
.
During the Vietnam war, between 1962 and 1971, the United States military sprayed of chemical herbicides and defoliants in Vietnam, eastern Laos and parts of Cambodia, as part of Operation Ranch Hand.[Pellow, David N]
''Resisting Global Toxics: Transnational Movements for Environmental Justice''
MIT Press, 2007, p. 159, ().
By 1971, 12% of the total area of South Vietnam had been sprayed with defoliating chemicals, which were often applied at rates that were 13 times as high as the legal USDA limit.[SBSG, 1971]
p. 36
/ref> In South Vietnam alone, an estimated 10 million hectares
The hectare (; SI symbol: ha) is a non-SI metric unit of area equal to a square with 100-metre sides (1 hm2), or 10,000 m2, and is primarily used in the measurement of land. There are 100 hectares in one square kilometre. An acre is ab ...
of agricultural land were ultimately destroyed.[Luong, 2003]
p. 3
/ref> In some areas, TCDD concentrations in soil and water were hundreds of times greater than the levels considered safe by the U.S. Environmental Protection Agency
The Environmental Protection Agency (EPA) is an Independent agencies of the United States government, independent executive agency of the United States federal government tasked with environmental protection matters. President Richard Nixon pro ...
.[Fawthrop, Tom]
"Vietnam's war against Agent Orange"
''BBC News'', June 14, 2004[Fawthrop, Tom]
"Agent of Suffering"
''Guardian'', February 10, 2008
According to Vietnamese Ministry of Foreign Affairs, 4.8 million Vietnamese people were exposed to Agent Orange, resulting in 400,000 people being killed or maimed, and 500,000 children born with birth defects
A birth defect, also known as a congenital disorder, is an abnormal condition that is present at birth regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can ...
.[York, Geoffrey; Mick, Hayley]
"Last Ghost of the Vietnam War"
, ''The Globe and Mail'', July 12, 2008 The Red Cross of Vietnam
The Viet Nam Red Cross Society () is a member (National Society) of the International Federation of Red Cross and Red Crescent Societies and has its headquarters in Hanoi. The organisation was established during the First Indochina War, and orig ...
estimates that up to 1 million people are disabled or have health problems due to Agent Orange contamination. The United States government has challenged these figures as being unreliable and unrealistically high.
Dioxin exposure incidents
*In 1949, in a Monsanto
The Monsanto Company () was an American agrochemical and agricultural biotechnology corporation founded in 1901 and headquartered in Creve Coeur, Missouri. Monsanto's best known product is Roundup, a glyphosate-based herbicide, developed in th ...
herbicide production plant for 2,4,5-T in Nitro, West Virginia
Nitro is a city in Kanawha and Putnam counties in the State of West Virginia, named after a World War I era nitrocellulose plant built by the government. The population was 6,518 according to the 2021 Population estimates.
History
Nitro was in ...
, 240 people were affected when a relief valve opened.
*In 1963, a dioxin cloud escaped after an explosion in a Philips
Koninklijke Philips N.V. (), commonly shortened to Philips, is a Dutch multinational conglomerate corporation that was founded in Eindhoven in 1891. Since 1997, it has been mostly headquartered in Amsterdam, though the Benelux headquarters i ...
-Duphar plant (now Solvay Solvay may refer to:
Companies and organizations
* Solvay Brussels School of Economics and Management, Brussels, Belgium
* Solvay Conference, founded by Ernest Solvay, deals with open questions in physics and chemistry
* Solvay Indupa, an Argen ...
Group) near Amsterdam
Amsterdam ( , , , lit. ''The Dam on the River Amstel'') is the Capital of the Netherlands, capital and Municipalities of the Netherlands, most populous city of the Netherlands, with The Hague being the seat of government. It has a population ...
. The plant was so polluted with dioxin after the accident that it had to be dismantled, embedded in concrete, and dumped into the ocean.
*
Between 1965 and 1968 production of 2,4,5-trichlorophenol in Spolana
SPOLANA s.r.o. is a chemical factory located on the Elbe riverbank in Neratovice, Czech Republic. It is oriented mainly towards exporting its products, and exports represent more than 80% of its total production. It currently concentrates on the p ...
Neratovice
Neratovice (; german: Neratowitz) is a town in Mělník District in the Central Bohemian Region of the Czech Republic. It has about 16,000 inhabitants. It is an industrial town.
Administrative parts
Villages of Byškovice, Horňátky, Korycany, Lo ...
plant in Czechoslovakia
, rue, Чеськословеньско, , yi, טשעכאסלאוואקיי,
, common_name = Czechoslovakia
, life_span = 1918–19391945–1992
, p1 = Austria-Hungary
, image_p1 ...
seriously poisoned about 60 workers with dioxins; after 3 years of investigation of the health problems of workers, Spolana stopped manufacture of 2,4,5-T (most of which was supplied to the US military in Vietnam
Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...
). Several buildings of the Spolana chemical plant were heavily contaminated by dioxins. Unknown amounts of dioxins were flushed into the Elbe
The Elbe (; cs, Labe ; nds, Ilv or ''Elv''; Upper and dsb, Łobjo) is one of the major rivers of Central Europe. It rises in the Giant Mountains of the northern Czech Republic before traversing much of Bohemia (western half of the Czech Repu ...
and Mulde
The Mulde () is a river in Saxony and Saxony-Anhalt, Germany. It is a left tributary of the Elbe and is long.
The river is formed by the confluence, near Colditz, of the Zwickauer Mulde (running through Zwickau) and the Freiberger Mulde (with ...
rivers during the 2002 European flood
In August 2002, a week of intense rainfall produced flooding across a large portion of Europe. It reached the Czech Republic, Italy, Spain, Austria, Germany, Slovakia, Hungary, Romania, Bulgaria, Croatia, Ukraine and Russia. The event killed 232 ...
, contaminating soil. Analysis of eggs and ducks found dioxin levels 15 times higher than the EU limit and a high concentration of dioxin-like PCBs in the village of Libiš
Libiš is a municipality and village in Mělník District in the Central Bohemian Region of the Czech Republic. It has about 2,300 inhabitants.
Geography
Libiš is located about north of Prague and creates a conurbation with the neighbouring tow ...
. In 2004, the state health authority published a study which analysed the level of toxic substances in human blood near Spolana. According to the study, dioxin levels in Neratovice
Neratovice (; german: Neratowitz) is a town in Mělník District in the Central Bohemian Region of the Czech Republic. It has about 16,000 inhabitants. It is an industrial town.
Administrative parts
Villages of Byškovice, Horňátky, Korycany, Lo ...
, Libiš and Tišice
Tišice is a municipality and village in Mělník District in the Central Bohemian Region of the Czech Republic. It has about 2,500 inhabitants.
Administrative parts
The villages of Chrást and Kozly are administrative parts of Tišice.
Geography ...
were about twice the level of the control group in Benešov
Benešov (; german: Beneschau; also known as Benešov u Prahy) is a town in the Central Bohemian Region of the Czech Republic. It has about 16,000 inhabitants. The town is known for the Konopiště Castle.
Administrative parts
Villages of Baba, ...
. The quantity of dioxins near Spolana is significantly higher than the background levels in other countries. According to the US EPA, even a background level can pose a risk of cancer from 1:10000 to 1:1000, about 100 times higher than normal. The consumption of local fish, eggs, poultry, and some produce was prohibited because of post-flood contamination.
*Also during 1965 through 1968, Dr. Albert M. Kligman was contracted by the Dow Chemical Company to perform threshold tests for TCDD on inmates at Holmesburg Prison
Holmesburg Prison, given the nickname "The Terrordome," was a prison operated by the city of Philadelphia, Pennsylvania and the Philadelphia Prison System, Pennsylvania Department of Prisons (PDP) from 1896 to 1995. The facility is located at 8 ...
in Philadelphia
Philadelphia, often called Philly, is the largest city in the Commonwealth of Pennsylvania, the sixth-largest city in the U.S., the second-largest city in both the Northeast megalopolis and Mid-Atlantic regions after New York City. Sinc ...
after Dow studies revealed adverse effects on workers at Dow's Midland, Michigan
Midland is a city in and the county seat of Midland County, Michigan. The city's population was 42,547 as of the 2020 census. It is the principal city of the Midland Micropolitan Statistical Area, part of the larger Saginaw-Midland-Bay City Comb ...
, plant were likely due to TCDD. A subsequent test by Dow in rabbit ear models when exposed to 4–8μg usually caused a severe response. The human studies carried out in Holmesburg failed to follow Dow's original protocol and lacked proper informed consent by the participants. As a result of poor study design and subsequent destruction of records, the tests were virtually worthless even though ten inmates were exposed to 7,500μg of TCDD.
*In 1976, large amounts of dioxins were released in an industrial accident at Seveso, Italy, although no immediate human fatalities or birth defects occurred.
*In 1978, dioxins were some of the contaminants that forced the evacuation of the Love Canal
Love Canal is a neighborhood in Niagara Falls, New York, United States, infamous as the location of a landfill that became the site of an enormous environmental disaster in the 1970s. Decades of dumping toxic chemicals harmed the health of hund ...
neighborhood of Niagara Falls, New York
Niagara Falls is a City (New York), city in Niagara County, New York, United States. As of the 2020 United States Census, 2020 census, the city had a total population of 48,671. It is adjacent to the Niagara River, across from the city of Niagara ...
.
*From 1982 through to 1985, Times Beach, Missouri
Times Beach is a ghost town in St. Louis County, Missouri, United States, southwest of St. Louis and east of Eureka. Once home to more than two thousand people, the town was completely evacuated early in 1983 due to TCDD—also known as diox ...
, was bought out and evacuated under order of the United States Environmental Protection Agency
The Environmental Protection Agency (EPA) is an independent executive agency of the United States federal government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it be ...
due to high levels of dioxins in the soil caused by applications of contaminated oil meant to control dust on the town's dirt roads. The town eventually disincorporated.
*A chemical plant Khimprom in Ufa
Ufa ( ba, Өфө , Öfö; russian: Уфа́, r=Ufá, p=ʊˈfa) is the largest city and capital of Bashkortostan, Russia. The city lies at the confluence of the Belaya and Ufa rivers, in the centre-north of Bashkortostan, on hills forming the ...
, Russia released phenol
Phenol (also called carbolic acid) is an aromatic organic compound with the molecular formula . It is a white crystalline solid that is volatile. The molecule consists of a phenyl group () bonded to a hydroxy group (). Mildly acidic, it req ...
into the water tributaries in the Spring of 1990. An investigation revealed previously classified disposal of dioxin in manufacturing 2,4,5-Trichlorophenoxyacetic acid. The Spring 1990 accident affected 670,000 people. Dioxin was found in tap water. It was assumed that it resulted from chlorophenol
A chlorophenol is any organochloride of phenol that contains one or more covalently bonded chlorine atoms. There are five basic types of chlorophenols (mono- to pentachlorophenol) and 19 different chlorophenols in total when positional isomerism is ...
produced by a reaction with chlorine in water purification.
*In December 1991, an electrical explosion caused dioxins (created from the oxidation of 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 ...
) to spread through four residence hall
A dormitory (originated from the Latin word ''dormitorium'', often abbreviated to dorm) is a building primarily providing sleeping and residential quarters for large numbers of people such as boarding school, high school, college or university s ...
s and two other buildings on the college campus of SUNY New Paltz.
*In May 1999, there was a dioxin crisis in Belgium: quantities of polychlorinated biphenyls
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 of 1976, Toxic Substances Contro ...
with dioxin-like toxicity had entered the food chain
A food chain is a linear network of links in a food web starting from producer organisms (such as grass or algae which produce their own food via photosynthesis) and ending at an apex predator species (like grizzly bears or killer whales), det ...
through contaminated animal feed
Animal feed is food given to domestic animals, especially livestock, in the course of animal husbandry. There are two basic types: fodder and forage. Used alone, the word ''feed'' more often refers to fodder. Animal feed is an important input to ...
. 7,000,000 chickens and 60,000 pigs had to be slaughtered. This scandal was followed by a landslide change in government in the elections one month later.
*Explosions resulting from the terrorist attacks on the US on September 11, 2001
The September 11 attacks, commonly known as 9/11, were four coordinated suicide terrorist attacks carried out by al-Qaeda against the United States on Tuesday, September 11, 2001. That morning, nineteen terrorists hijacked four commerc ...
, released massive amounts of dust into the air. The air was measured for dioxins from September 23, 2001, to November 21, 2001, and reported to be "likely the highest ambient concentration that have ever been reported n history" The United States Environmental Protection Agency
The Environmental Protection Agency (EPA) is an independent executive agency of the United States federal government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it be ...
report dated October 2002 and released in December 2002 titled "Exposure and Human Health Evaluation of Airborne Pollution from the World Trade Center Disaster" authored by the EPA Office of Research and Development in Washington states that dioxin levels recorded at a monitoring station on Park Row near City Hall Park
City Hall Park is a public park surrounding New York City Hall in the Civic Center of Manhattan. It was the town commons of the nascent city of New York.
History
17th century
David Provoost was an officer in the Dutch West India Company. Hi ...
in New York
New York most commonly refers to:
* New York City, the most populous city in the United States, located in the state of New York
* New York (state), a state in the northeastern United States
New York may also refer to:
Film and television
* '' ...
between October 12 and 29, 2001, averaged 5.6 parts per trillion, or nearly six times the highest dioxin level ever recorded in the U.S. Dioxin levels in the rubble of the World Trade Centers
World Trade Centers are sites recognized by the World Trade Centers Association.
World Trade Center may refer to:
Buildings
* List of World Trade Centers
* World Trade Center (2001–present), a building complex that includes five skyscrapers, a ...
were much higher with concentrations ranging from 10 to 170 parts per trillion. The report did no measuring of the toxicity of indoor air.
*In a 2001 case study, physicians reported clinical changes in a 30-year-old woman who had been exposed to a massive dosage (144,000 pg/g blood fat) of dioxin equal to 16,000 times the normal body level; the highest dose of dioxin ever recorded in a human. She suffered from chloracne
Chloracne is an acne-like eruption of blackheads, cysts, and pustules associated with exposure to certain halogenated aromatic compounds, such as chlorinated dioxins and dibenzofurans. The lesions are most frequently found on the cheeks, behind ...
, nausea
Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the ...
, vomiting
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 Human nose, nose.
Vomiting can be the result of ailments like Food-poisoning, foo ...
, epigastric
In anatomy, the epigastrium (or epigastric region) is the upper central region of the abdomen. It is located between the costal margins and the subcostal plane. Pain may be referred to the epigastrium from damage to structures derived from the f ...
pain, loss of appetite
Anorexia is a medical term for a loss of appetite. While the term in non-scientific publications is often used interchangeably with anorexia nervosa, many possible causes exist for a loss of appetite, some of which may be harmless, while others i ...
, leukocytosis
Leukocytosis is a condition in which the white cell (leukocyte count) is above the normal range in the blood. It is frequently a sign of an inflammatory response, most commonly the result of infection, but may also occur following certain parasi ...
, anemia
Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, th ...
, amenorrhoea
Amenorrhea is the absence of a menstrual period in a woman of reproductive age. Physiological states of amenorrhoea are seen, most commonly, during pregnancy and lactation (breastfeeding). Outside the reproductive years, there is absence of menses ...
and thrombocytopenia
Thrombocytopenia is a condition characterized by abnormally low levels of platelets, also known as thrombocytes, in the blood. It is the most common coagulation disorder among intensive care patients and is seen in a fifth of medical patients an ...
. However, other notable laboratory tests, such as immune function tests, were relatively normal. The same study also covered a second subject who had received a dosage equivalent to 2,900 times the normal level, who apparently suffered no notable negative effects other than chloracne. These patients were provided with olestra
Olestra (also known by its brand name Olean) is a fat substitute that adds no calories to products. It has been used in the preparation of otherwise high-fat foods thereby lowering or eliminating their fat content. The Food and Drug Administrati ...
to accelerate dioxin elimination.
*
In 2004, in a notable individual case of dioxin poisoning, Ukrainian
Ukrainian may refer to:
* Something of, from, or related to Ukraine
* Something relating to Ukrainians, an East Slavic people from Eastern Europe
* Something relating to demographics of Ukraine in terms of demography and population of Ukraine
* So ...
politician Viktor Yushchenko
Viktor Andriyovych Yushchenko ( uk, Віктор Андрійович Ющенко, ; born 23 February 1954) is a Ukrainian politician who was the third president of Ukraine from 23 January 2005 to 25 February 2010.
As an informal leader of th ...
was exposed to the second-largest measured dose of dioxins, according to the reports of the physicians responsible for diagnosing him. This is the first known case of a single high dose of TCDD dioxin poisoning, and was diagnosed only after a toxicologist recognized the symptoms of chloracne
Chloracne is an acne-like eruption of blackheads, cysts, and pustules associated with exposure to certain halogenated aromatic compounds, such as chlorinated dioxins and dibenzofurans. The lesions are most frequently found on the cheeks, behind ...
while viewing television news coverage of his condition.
*In the early 2000s, residents of the city of New Plymouth
New Plymouth ( mi, Ngāmotu) is the major city of the Taranaki region on the west coast of the North Island of New Zealand. It is named after the English city of Plymouth, Devon from where the first English settlers to New Plymouth migrated. ...
, New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...
, reported many illnesses of people living around and working at the Dow Chemical plant. This plant ceased production of 2,4,5-T in 1987.
*DuPont has been sued by 1,995 people who claim dioxin emissions from DuPont's plant in DeLisle, Mississippi
DeLisle () is a census-designated place (CDP) in Harrison County, Mississippi, United States. It is part of the Gulfport– Biloxi Metropolitan Statistical Area. The population was 1,147 at the 2010 census.
Geography
DeLisle is located at . ...
, caused their cancers, illnesses or loved ones' deaths; of these only 850 were pending as of June 2008. In August 2005, Glen Strong, an oyster
Oyster is the common name for a number of different families of salt-water bivalve molluscs that live in marine or brackish habitats. In some species, the valves are highly calcified, and many are somewhat irregular in shape. Many, but not al ...
fisherman with the rare blood cancer multiple myeloma
Multiple myeloma (MM), also known as plasma cell myeloma and simply myeloma, is a cancer of plasma cells, a type of white blood cell that normally produces antibodies. Often, no symptoms are noticed initially. As it progresses, bone pain, an ...
, was awarded $14 million from DuPont, but the ruling was overturned June 5, 2008, by a Mississippi
Mississippi () is a state in the Southeastern region of the United States, bordered to the north by Tennessee; to the east by Alabama; to the south by the Gulf of Mexico; to the southwest by Louisiana; and to the northwest by Arkansas. Miss ...
jury who found DuPont's plant had no connection to Mr. Strong's disease. In another case, parents claimed dioxin from pollution caused the death of their 8-year-old daughter; the trial took place in the summer of 2007, and a jury wholly rejected the family's claims, as no scientific connection could be proven between DuPont and the family's tragic loss. DuPont's DeLisle plant is one of three titanium dioxide
Titanium dioxide, also known as titanium(IV) oxide or titania , is the inorganic compound with the chemical formula . When used as a pigment, it is called titanium white, Pigment White 6 (PW6), or CI 77891. It is a white solid that is insolubl ...
facilities (including Edgemoor, Delaware
Edgemoor is a census-designated place in New Castle County, Delaware, United States. The population was 5,677 at the 2010 census.
Geography
Edgemoor is located at (39.7501139, -75.4996414).
According to the United States Census Bureau, the CDP ...
, and New Johnsonville, Tennessee
New Johnsonville is a city in Humphreys County, Tennessee, United States. The population was 1,951 at the 2010 census.
History
The history of New Johnsonville is rooted in the town of Johnsonville, which was once situated on the Tennessee Rive ...
) that are the largest producers of dioxin in the country, according to the US EPA's Toxic Release Inventory. DuPont maintains its operations are safe and environmentally responsible.
*In 2007, thousands of tonnes of foul-smelling refuse were piled up in Naples
Naples (; it, Napoli ; nap, Napule ), from grc, Νεάπολις, Neápolis, lit=new city. is the regional capital of Campania and the third-largest city of Italy, after Rome and Milan, with a population of 909,048 within the city's adminis ...
, Italy and its surrounding villages, defacing entire neighbourhoods. Authorities discovered that polychlorinated dibenzodioxins levels in buffalo milk used by 29 mozzarella makers exceeded permitted limits; after further investigation they impounded milk from 66 farms. Authorities suspected the source of the contamination was from waste illegally disposed of on land grazed by buffalo. Prosecutors in Naples placed 109 people under investigation on suspicion of fraud and food poisoning. Sales of Mozzarella cheese fell by 50% in Italy.
*In December 2008 in Ireland
Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...
dioxin levels in pork
Pork is the culinary name for the meat of the domestic pig (''Sus domesticus''). It is the most commonly consumed meat worldwide, with evidence of pig husbandry dating back to 5000 BCE.
Pork is eaten both freshly cooked and preserved; ...
were disclosed to have been between 80 and 200 times the legal limit. All Irish pork products were withdrawn from sale both nationally and internationally. In this case the dioxin toxicity was found to be mostly due to dioxin-like polychlorinated dibenzofurans
Dibenzofuran is a heterocyclic organic compound with the chemical structure shown at right. It is an aromatic compound that has two benzene rings fused to a central furan ring. All the numbered carbon atoms have a hydrogen atom bonded to each of th ...
and polychlorinated biphenyls
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 of 1976, Toxic Substances Contro ...
, and the contribution from actual polychlorinated dibenzodioxins was relatively low. It is thought that the incident resulted from the contamination of fuel oil
Fuel oil is any of various fractions obtained from the distillation of petroleum (crude oil). Such oils include distillates (the lighter fractions) and residues (the heavier fractions). Fuel oils include heavy fuel oil, marine fuel oil (MFO), bun ...
used in a drying burner at a single feed processor, with PCBs. The resulting combustion produced a highly toxic mixture of PCBs, dioxins and furan
Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen atom. Chemical compounds containing such rings are also referred to as furans.
Furan is a colorless, flammable, highly ...
s, which was included in the feed produced and subsequently fed to a large number of pigs.
*According to data in 2009, in 2005 the production of dioxin by the steel industry ILVA
ILVA is a Danish chain of furniture stores, offering mostly Scandinavian-style bed-, dining- and living room products. The company was founded in 1974, and currently runs eight stores in the Nordic countries. It also had three stores in Brit ...
in Taranto
Taranto (, also ; ; nap, label= Tarantino, Tarde; Latin: Tarentum; Old Italian: ''Tarento''; Ancient Greek: Τάρᾱς) is a coastal city in Apulia, Southern Italy. It is the capital of the Province of Taranto, serving as an important com ...
(Italy
Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical re ...
) accounted for 90.3 per cent of the overall Italian emissions, and 8.8 per cent of the European emissions.
*German dioxin incident: In January 2011 about 4700 German farms were banned from making deliveries after self-checking of an animal feed producer had showed levels of dioxin above maximum levels. This incident appeared to involve PCDDs and not PCBs. Dioxins were found in animal feed and eggs in many farms. The maximum values were exceeded twofold in feed and maximally fourfold in some individual eggs.[ Thus the incident was minor as compared with the Belgian crisis in 1999, and delivery bans were rapidly cleared.]
Dioxin testing
The analyses used to determine these compounds' relative toxicity share common elements that differ from methods used for more traditional analytical determinations. The preferred methods for dioxins and related analyses use high resolution gas chromatography/mass spectrometry (HRGC/HRMS). Concentrations are determined by measuring the ratio of the analyte to the appropriate isotopically labeled internal standard.
Also novel bio-assays like DR CALUX are nowadays used in identification of dioxins and dioxin-like compounds. The advantage in respect to HRGC/HRMS is that it is able to scan many samples at lower costs. Also it is able to detect all compounds that interact with the Ah-receptor which is responsible for carcinogenic effects.
See also
*Dioxins and dioxin-like compounds
Dioxins and dioxin-like compounds (DLCs) are a group of chemical compounds that are persistent organic pollutants (POPs) in the environment. They are mostly by-products of burning or various industrial processes - or, in case of dioxin-like PCBs an ...
*Polychlorinated dibenzofurans
More thorough treatise of all groups with similar actions and binding to aryl hydrocarbon receptor is given in Dioxins and dioxin-like compounds.
Polychlorinated dibenzofurans (PCDFs) are a family of organic compounds with one or several of the ...
(PCDFs) – A group of compounds, produced by the same conditions as dioxins and commonly co-present with dioxins in contamination incidents. They have the same toxic mode of action and are included in the toxic equivalent Toxic equivalency factor (TEF) expresses the toxicity of Polychlorinated dibenzodioxins, dioxins, Polychlorinated dibenzofurans, furans and Polychlorinated biphenyl, PCBs in terms of the most toxic form of dioxin, 2,3,7,8-TCDD.Van den Berg M, Birnba ...
scheme for the purposes of assessing dioxin levels.
*Chemetco
Chemetco was formerly one of the largest United States refiners of copper from recycled or residual sources.
Its maximum output of 120,000 tons per year was approximately half of the entire U.S. copper output from recycled copper. The company w ...
– this former copper smelter is cited in an academic study as one of the 10 highest ranking sources of dioxin pollution reaching Nunavut in the Canadian Arctic
*Polychlorinated biphenyls
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 of 1976, Toxic Substances Contro ...
– A group of compounds historically used in the manufacture of electrical transformers certain members of which can also contribute to dioxin-like toxicity. These dioxin like compounds are also included in the toxic equivalent Toxic equivalency factor (TEF) expresses the toxicity of Polychlorinated dibenzodioxins, dioxins, Polychlorinated dibenzofurans, furans and Polychlorinated biphenyl, PCBs in terms of the most toxic form of dioxin, 2,3,7,8-TCDD.Van den Berg M, Birnba ...
scheme when measuring dioxin levels.
References
External links
NIEHS dioxin fact sheet
"Dioxins and Dioxin-like Compounds in the Food Supply: Strategies to Decrease Exposure"
, a 2003 report by the National Academy of Sciences
The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nati ...
"Assessment of the Health Risks of Dioxins"
a 1998 report by the World Health Organization
The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level of h ...
.
{{DEFAULTSORT:Polychlorinated Dibenzodioxins
Chloroarenes
IARC Group 1 carcinogens
IARC Group 3 carcinogens
Immunotoxins
Dibenzodioxins
Persistent organic pollutants under the Convention on Long-Range Transboundary Air Pollution
Persistent organic pollutants under the Stockholm Convention