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Phthalates (pronounced 〔": video of Steve Risotto of the American Chemistry Council, uploaded by user AmericanChemistry on 23 Oct 2009, retrieved 23 Dec 2011.〕 or in British English /ˈ(f)θaleɪts/〔(【引用サイトリンク】title=phthalate, n. )〕), or phthalate esters, are esters of phthalic acid and are mainly used as plasticizers (substances added to plastics to increase their flexibility, transparency, durability, and longevity). Phthalates are manufactured by reacting phthalic anhydride with alcohol(s) that range from methanol and ethanol (C1/C2) up to tridecyl alcohol (C13), either as a straight chain or with some branching. They are divided into two distinct groups, with very different applications, toxicological properties, and classification, based on the number of carbon atoms in their alcohol chain. They are used primarily to soften polyvinyl chloride (PVC). Lower-molecular-weight phthalates (3-6 carbon atoms in their backbone) are being gradually replaced in many products in the United States, Canada, and European Union over health concerns. They are replaced by high-molecular-weight phthalates (those with more than 6 carbons in their backbone, which gives them increased permanency and durability). In 2010, the market was still dominated by high-phthalate plasticizers; however, due to legal provisions and growing environmental awareness and perceptions, producers are increasingly forced to use non-phthalate plasticizers.〔(【引用サイトリンク】Plasticizers – Study: Market, Analysis, Trends - Ceresana )〕 Phthalates are used in a wide range of common products, and are released into the environment.〔(ehp.1205256_508 ) (PDF)〕 There is no covalent bond between the phthalates and plastics; rather, they are entangled within the plastic as a result of the manufacturing process used to make PVC articles.〔(bilder.buecher.de ) (PDF)〕 They can be removed by exposure to heat or with organic solvents. However, people are exposed to phthalates, and most Americans tested by the Centers for Disease Control and Prevention have metabolites of multiple phthalates in their urine.〔(Pthalates FactSheet ) (PDF)〕 Phthalate exposure may be through direct use or by indirect means through leaching and general environmental contamination. Diet is believed to be the main source of di(2-ethylhexyl) phthalate (DEHP) and other phthalates in the general population.〔 Fatty foods such as milk, butter, and meats are a major source.〔(【引用サイトリンク】title=4. To what extent are people exposed to phthalates? )〕 In studies of rodents exposed to certain phthalates, high doses have been shown to change hormone levels and cause birth defects.〔 ==Uses== Phthalates are used in a large variety of products, from enteric coatings of pharmaceutical pills and nutritional supplements to viscosity control agents, gelling agents, film formers, stabilizers, dispersants, lubricants, binders, emulsifying agents, and suspending agents. End-applications include adhesives and glues, agricultural adjuvants, building materials, personal-care products, medical devices, detergents and surfactants, packaging, children's toys, modelling clay, waxes, paints, printing inks and coatings, pharmaceuticals, food products, and textiles. Phthalates are also frequently used in soft plastic fishing lures, caulk, paint pigments, and sex toys made of so-called "jelly rubber". Phthalates are used in a variety of household applications such as shower curtains, vinyl upholstery, adhesives, floor tiles, food containers and wrappers, and cleaning materials. Personal-care items containing phthalates include perfume, eye shadow, moisturizer, nail polish, liquid soap, and hair spray. Phthalates are also found in modern electronics and medical applications such as catheters and blood transfusion devices. The most widely used phthalates are di(2-ethylhexyl) phthalate (DEHP), diisodecyl phthalate (DIDP), and diisononyl phthalate (DINP). DEHP was the dominant plasticizer used globally in PVC due to its low cost. Benzylbutylphthalate (BBP) is used in the manufacture of foamed PVC, which is used mostly as a flooring material, though its use is decreasing rapidly in the Western countries. Phthalates with small R and R' groups are used as solvents in perfumes and pesticides. Approximately seven million tonnes of plasticizers are consumed globally every year, of which European consumption accounts for approximately 1 million tonnes. They contribute 10-60% of plasticized products by weight.〔 More recently in Europe and the US, regulatory developments have resulted in a change in phthalate consumption, with the higher phthalates (DINP and DIDP) replacing DEHP as the general purpose plasticizer of choice because DIDP and DINP were not classified as hazardous. All of these mentioned phthalates are now regulated and restricted in many products. DEHP, although most applications are shown to pose no risk when studied using recognized methods of risk assessment, has been classified as a Category 1A reprotoxin, and is now on the Annex XIV of the European Union's REACH legislation, which means that producers and users must submit authorization requests to the European Chemicals Agency in Helsinki in order to continue to use DEHP. Analysis of such applications will involve studies on alternatives and, given the wide number of compounds that have been used as plasticizers, such evaluations are likely to be far-reaching. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「phthalate」の詳細全文を読む スポンサード リンク
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