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|Section2= |Section3= |Section7= |Section8= }} Bisphenol A (BPA) is an organic synthetic compound with the chemical formula (CH3)2C(C6H4OH)2 belonging to the group of diphenylmethane derivatives and bisphenols, with two hydroxyphenyl groups. It is a colorless solid that is soluble in organic solvents, but poorly soluble in water. It has been in commercial use since 1957. BPA is employed to make certain plastics and epoxy resins. BPA-based plastic is clear and tough, and is made into a variety of common consumer goods, such as water bottles, sports equipment, CDs, and DVDs. Epoxy resins containing BPA are used to line water pipes, as coatings on the inside of many food and beverage cans and in making thermal paper such as that used in sales receipts. In 2011, an estimated 10 billion pounds of BPA chemical were produced for manufacturing polycarbonate plastic, making it one of the highest volume of chemicals produced worldwide. BPA exhibits hormone-like properties that raise concern about its suitability in some consumer products and food containers. Since 2008, several governments have investigated its safety, which prompted some retailers to withdraw polycarbonate products. The FDA has ended its authorization of the use of BPA in baby bottles and infant formula packaging, based on market abandonment, not safety. The European Union and Canada have banned BPA use in baby bottles. A 2010 report from the US Food and Drug Administration (FDA) identified possible hazards to fetuses, infants, and young children. However, an FDA assessment released in March 2013 said that BPA is safe at the very low levels that occur in some foods.〔(【引用サイトリンク】title=Bisphenol A (BPA): Use in Food Contact Application )〕 In July 2014, the FDA updated its perspective on the use of BPA in food contact applications, confirming that "BPA is safe at the current levels occurring in foods" based on extensive research, including two more studies issued by the agency in early 2014.〔(【引用サイトリンク】title=Bisphenol A (BPA): Use in Food Contact Application )〕 The European Food Safety Authority (EFSA) reviewed new scientific information on BPA in 2008, 2009, 2010, 2011 and 2015: EFSA’s experts concluded on each occasion that they could not identify any new evidence which would lead them to revise their opinion that the presently known levels of exposure to BPA is safe; however, EFSA does recognize some uncertainties, and will continue to investigate them.〔(EFSA Topic: Bisphenol A )〕 ==Production== World production capacity of this compound was 1 million tons in the 1980s,〔 and more than 2.2 million tons in 2009. and thus belongs to the high production volume chemicals. In 2003, U.S. consumption was 856,000 tons, 72% of which used to make polycarbonate plastic and 21% going into epoxy resins. In the U.S., less than 5% of the BPA produced is used in food contact applications,〔 but remains in the canned food industry and printing applications such as sales receipts. Bisphenol A was first synthesized by the Russian chemist A.P. Dianin in 1891.〔 See especially p. 492.〕 This compound is synthesized by the condensation of acetone (hence the suffix A in the name) with two equivalents of phenol. The reaction is catalyzed by a strong acid, such as hydrochloric acid (HCl) or a sulfonated polystyrene resin. Industrially, a large excess of phenol is used to ensure full condensation; the product mixture of the cumene process (acetone and phenol) may also be used as starting material:〔 : A large number of ketones undergo analogous condensation reactions. Commercial production of BPA requires distillation – either extraction of BPA from many resinous byproducts under high vacuum or solvent-based extraction using additional phenol followed by distillation. 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「Bisphenol A」の詳細全文を読む スポンサード リンク
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