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Pentachlorobenzene
Pentachlorobenzene (PeCB) is a chemical compound with the molecular formula C6HCl5 which is a chlorinated aromatic hydrocarbon. It consists of a benzene ring substituted with five chlorine atoms. PeCB was once used industrially for a variety of uses, but because of environmental concerns there are currently no large scale uses of PeCB.Pentachlorobenzene – Sources, environmental fate and risk characterization , Robert E. Bailey, EuroChlor, July 2007 Pentachlorobenzene is a known (POP) and banned globally by the |
Pentachlorobenzenethiol
Pentachlorobenzenethiol is a chemical compound from the group of thiols and organochlorine compounds. The chemical formula is . Synthesis Pentachlorobenzenethiol can be obtained from hexachlorobenzene. Properties Pentachlorobenzenethiol is a combustible gray solid with an unpleasant odor, practically insoluble in water. It has a monoclinic crystal structure. The compound is not well-biodegradable and presumably bioaccumulable and toxic for aquatic organisms. Pentachlorobenzenethiol is itself a metabolite of hexachlorobenzene and is found in the urine and the excretions of animals receiving hexachlorobenzene. Pentachlorobenzenethiol has a high potential for long-range transport via air as it is very slowly degraded in atmosphere. Applications Pentachlorobenzenethiol is used in the rubber industry. The compound is added to rubber (both natural and synthetic) to facilitate processing (mastication). See also *Chlorobenzene *Dichlorobenzene *Trichlorobenzene *Pentachlorobenzene *Hex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexachlorobenzene
Hexachlorobenzene, or perchlorobenzene, is an organochloride with the molecular formula C6Cl6. It is a fungicide formerly used as a seed treatment, especially on wheat to control the fungal disease bunt. It has been banned globally under the Stockholm Convention on Persistent Organic Pollutants. Physical and chemical properties Hexachlorobenzene is a stable, white, crystalline chlorinated hydrocarbon. It is sparingly soluble in organic solvents such as benzene, diethyl ether and alcohol, but practically insoluble in water with no reaction. It reacts violently above 65 °C with dimethyl formamide and has a flash point of 468 °F. It is stable under normal temperatures and pressures. It is combustible but it does not ignite readily. When heated to decomposition, hexachlorobenzene emits highly toxic fumes of hydrochloric acid, other chlorinated compounds (such as phosgene), carbon monoxide, and carbon dioxide. Synthesis Hexachlorobenzene has been made on a laboratory scale since t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 affect human health and the environment around the world. Because they can be transported by wind and water, most POPs generated in one country can and do affect people and wildlife far from where they are used and released. The effect of POPs on human and environmental health was discussed, with intention to eliminate or severely restrict their production, by the international community at the Stockholm Convention on Persistent Organic Pollutants in 2001. Most POPs are pesticides or insecticides, and some are also solvents, pharmaceuticals, and industrial chemicals. Although some POPs arise naturally (e.g. from volcanoes), most are man-made. The "dirty dozen" POPs identified by the Stockholm Convention include aldrin, chlordane, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentafluorobenzene
Pentafluorobenzene is an organofluoride compound with the molecular formula . The compound consists of a benzene ring substituted with five fluorine atoms. The substance is a colorless liquid with a boiling point similar to that of benzene.''CRC Handbook of Chemistry and Physics'', 90. Edition, CRC Press, Boca Raton, Florida, 2009, , Section 3, ''Physical Constants of Organic Compounds'', p. 3-414. It is prepared by defluorination of highly fluorinated cyclohexanes over hot nickel or iron. Another method involved dehydrofluorination of polyfluorinated cyclohexane using hot aqueous solution of KOH. See also *Hexafluorobenzene *Pentachlorobenzene *Fluorobenzene Fluorobenzene is the chemical compound with the formula C6H5F, often abbreviated PhF. A colorless liquid, it is a precursor to many fluorophenyl compounds. Preparation PhF was first reported in 1886 by O. Wallach at the University of Bonn, who ... References {{Reflist Fluoroarenes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Persistent Organic Pollutants
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 affect human health and the environment around the world. Because they can be transported by wind and water, most POPs generated in one country can and do affect people and wildlife far from where they are used and released. The effect of POPs on human and environmental health was discussed, with intention to eliminate or severely restrict their production, by the international community at the Stockholm Convention on Persistent Organic Pollutants in 2001. Most POPs are pesticides or insecticides, and some are also solvents, pharmaceuticals, and industrial chemicals. Although some POPs arise naturally (e.g. from volcanoes), most are man-made. The "dirty dozen" POPs identified by the Stockholm Convention include aldrin, chlordane, die ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stockholm Convention On Persistent Organic Pollutants
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 pollutants (POPs). History In 1995, the Governing Council of the United Nations Environment Programme (UNEP) called for global action to be taken on POPs, which it defined as "chemical substances that persist in the environment, bio-accumulate through the food web, and pose a risk of causing adverse effects to human health and the environment". Following this, the Intergovernmental Forum on Chemical Safety (IFCS) and the International Programme on Chemical Safety (IPCS) prepared an assessment of the 12 worst offenders, known as the ''dirty dozen''. The INC met five times between June 1998 and December 2000 to elaborate the convention, and delegates adopted the Stockholm Convention on POPs at the Conference of the Plenipotentiaries ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Programme On Chemical Safety
The International Programme on Chemical Safety (IPCS) was formed in 1980 and is a collaboration between three United Nations bodies, the World Health Organization, the International Labour Organization and the United Nations Environment Programme, to establish a scientific basis for safe use of chemicals and to strengthen national capabilities and capacities for chemical safety. A related joint project with the same aim, IPCS INCHEM, is a collaboration between IPCS and the Canadian Centre for Occupational Health and Safety (CCOHS). The IPCS identifies the following as "chemicals of major public health concern": *Air pollution *Arsenic * Asbestos *Benzene *Cadmium * Dioxin and dioxin-like substances *Inadequate or excess fluoride *Lead * Mercury *Highly hazardous pesticides See also * Acceptable daily intake *International Chemical Safety Card *Concise International Chemical Assessment Document * Food safety Food safety (or food hygiene) is used as a scientific method/disci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trichlorobenzene
Trichlorobenzene (TCB) may refer to any of three isomeric chlorinated derivatives of benzene with the molecular formula C6H3Cl3. Trichlorobenzenes are man-made chemical compounds that occur in three different forms. Even though the forms have the same molecular weight and molecular formulae, they are structurally different by the positions of the chlorine atoms attached to the benzene ring. 1,2,3-Trichlorobenzene and 1,3,5-trichlorobenzene are colorless solids, but 1,2,4-trichlorobenzene is a colorless oil. The isomers may also have different chemical and toxicological properties. Identification numbers and regulations * 1,2,3-Trichlorobenzene - EC number 201-757-1, CAS number 87-61-6, substance subjected to REACH Registration, added to the list ofSubmitted SVHC Intentions List* 1,2,4-Trichlorobenzene 1,2,4-Trichlorobenzene is an organochlorine compound, one of three isomers of trichlorobenzene. It is a derivative of benzene with three chloride substituents. It is a colorle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dichlorobenzene
There are three distinct chemical compounds which are dichlorobenzenes: *1,2-Dichlorobenzene or ''ortho''-dichlorobenzene; *1,3-Dichlorobenzene or ''meta''-dichlorobenzene; *1,4-Dichlorobenzene or ''para''-dichlorobenzene. All three isomers are colorless organic compounds with the formula CHCl. They differ structurally based on where the two chlorine atoms are attached to the ring, like bracelets with two beads of one color and four beads of another color. Biodegradation '' Rhodococcus phenolicus'' is a bacterium species able to degrade dichlorobenzene as its sole carbon Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes ... source. References {{Authority control Chlorobenzenes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorobenzene
Chlorobenzene is an aromatic organic compound with the chemical formula C6H5Cl. This colorless, flammable liquid is a common solvent and a widely used intermediate in the manufacture of other chemicals. Uses Historical The major use of chlorobenzene is as an intermediate in the production of herbicides, dyestuffs, and rubber. Chlorobenzene is also used as a high-boiling solvent in industrial applications as well as in the laboratory. Chlorobenzene is nitrated on a large scale to give a mixture of 2-nitrochlorobenzene and 4-nitrochlorobenzene, which are separated. These mononitrochlorobenzenes are converted to related 2-nitrophenol, 2-nitroanisole, bis(2-nitrophenyl)disulfide, and 2-nitroaniline by nucleophilic displacement of the chloride, with respectively sodium hydroxide, sodium methoxide, sodium disulfide, and ammonia. The conversions of the 4-nitro derivative are similar. Chlorobenzene once was used in the manufacture of pesticides, most notably DDT, by reaction w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polychlorinated Dibenzofuran
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 hydrogens in the dibenzofuran structure replaced by chlorines. For example, 2,3,7,8-tetrachlorodibenzofuran (TCDF) has chlorine atoms substituted for each of the hydrogens on the number 2, 3, 7, and 8 carbons (see structure in the upper left corner of the second image). Polychlorinated dibenzofurans with chlorines at least in positions 2,3,7 and 8 are much more toxicity, toxic than the parent compound dibenzofurane, with properties and chemical structures similar to polychlorinated dibenzodioxins. These groups together are often inaccurately called Dioxins and dioxin-like compounds, dioxins. They are known developmental toxicants, and suspected human carcinogens. PCDFs tend to co-occur with polychlorinated dibenzodioxins (PCDDs). PCDFs can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
