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{| align="right" border="1" cellspacing="0" cellpadding="3" style="margin: 0 0 0 0.5em; background: #FFFFFF; border-collapse: collapse; border-color: #C0C090;"
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'''Bisphenol A''' is a ] that is prepared by ] of two equivalents of ] with one equivalent of ]. Its ] is shown at right. Bisphenol A belongs to the ] class of ] ]s, having two phenol ]s in its ].


! bgcolor="#a0ffa0" colspan="2"| '''{{PAGENAME}}''' <!-- replace if not identical with the article name -->
Bisphenol A was invented in the 1930's during the search for synthetic ]. At that time, another synthesized compound, ], turned out to be more powerful as an estrogen, so bisphenol A was shelved until ] chemists discovered that it could be polymerized to form ] ]. Its current main use is in the manufacture of polycarbonate polymers and ] glues.
|-
| ]
| 4,4'-(propan-2-ylidene)diphenol<br />{{PAGENAME}}
|-
| colspan=2 | ]
|-
| ]
| C<sub>15</sub>H<sub>16</sub>O<sub>2</sub>
|-
| ]
| 228.2902
|-
| ]
| 153&deg;C
|-
| ]
| 220&deg;C at 4 mm Hg <br />222&deg;C at 3 mm Hg
|-
| ]
| 227°C
|-
| ]
| 80-05-7
|-
|}
</div>

'''Bisphenol A''' is a ] that is prepared by ] of two equivalents of ] with one equivalent of ]. Bisphenol A belongs to the ] class of ] ]s; it has two phenol ]s in its ]. Bisphenol A was first synthesized by Dianin in 1891.

Bisphenol A was investigated in the 1930s during the search for synthetic ]. At that time, another synthesized compound, ], turned out to be more powerful as an estrogen, so bisphenol A was shelved until ] chemists discovered that it could be polymerized to form ] ]. Its current main use is in the manufacture of polycarbonate polymers and ] glues.


Polycarbonates are widely used in all sorts of consumer products, from ] and ] to water and food containers and shatter-resistant baby bottles. Some polymers used in ] also contain bisphenol A, while epoxy resins containing bisphenol A are popular coatings for the inside of cans used for canning food. Polycarbonates are widely used in all sorts of consumer products, from ] and ] to water and food containers and shatter-resistant baby bottles. Some polymers used in ] also contain bisphenol A, while epoxy resins containing bisphenol A are popular coatings for the inside of cans used for canning food.


== Possible Health Risks == == Possible Health Risks ==

BPA has been known to leach from plastics which are cleaned with harsh detergents or used to contain acidic or high temperature liquids. The chemical has been found in nearly every human tested in the United States. BPA has been known to leach from plastics which are cleaned with harsh detergents or used to contain acidic or high temperature liquids. The chemical has been found in nearly every human tested in the United States.


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A previous report, released by the ] Center for Risk Analysis and funded by the ], called the evidence for risks "weak" and "inconsistent". A previous report, released by the ] Center for Risk Analysis and funded by the ], called the evidence for risks "weak" and "inconsistent".


==References==

* Dianin, ''Zhurnal russkogo fiziko-khimicheskogo obshchestva'', 23 (1891), pp. 492 ff.

* Mittheilungen aus dem chemischen Laboratorium der Universit&auml;t Marburg, T. Zincke, ''Justus Leibigs Annals Chemie'', 343 (1905), pp. 75-99.

==External Links==


==External Sources:==



Revision as of 02:36, 17 May 2005

Bisphenol A
Chemical name 4,4'-(propan-2-ylidene)diphenol
Bisphenol A
Chemical structure of Bisphenol A
Chemical formula C15H16O2
Molecular Weight 228.2902
Melting point 153°C
Boiling point 220°C at 4 mm Hg
222°C at 3 mm Hg
Flashpoint 227°C
CAS number 80-05-7

Bisphenol A is a chemical compound that is prepared by reaction of two equivalents of phenol with one equivalent of acetone. Bisphenol A belongs to the phenol class of aromatic organic compounds; it has two phenol functional groups in its molecule. Bisphenol A was first synthesized by Dianin in 1891.

Bisphenol A was investigated in the 1930s during the search for synthetic estrogens. At that time, another synthesized compound, diethylstilbestrol, turned out to be more powerful as an estrogen, so bisphenol A was shelved until polymer chemists discovered that it could be polymerized to form polycarbonate plastic. Its current main use is in the manufacture of polycarbonate polymers and epoxy glues.

Polycarbonates are widely used in all sorts of consumer products, from sunglasses and CDs to water and food containers and shatter-resistant baby bottles. Some polymers used in dental fillings also contain bisphenol A, while epoxy resins containing bisphenol A are popular coatings for the inside of cans used for canning food.

Possible Health Risks

BPA has been known to leach from plastics which are cleaned with harsh detergents or used to contain acidic or high temperature liquids. The chemical has been found in nearly every human tested in the United States.

The first evidence of bisphenol A's estrogenicity came from experiments in the 1930's feeding BPA to ovariectomised rats (Dodds and Lawson 1936, 1938). Some hormone disrupting effects in studies on animals and human cancer cells have been shown to occur at levels as low as 2-5 ppb (parts per billion).

The plastics industry has long claimed that bisphenol A is safe at typical levels of human exposure, minimizing or discounting all tests to the contrary. Eleven industry-funded studies found no risk from bisphenol A, while 90% of 104 independent studies showed possible risks, says a December 2004 report from scientists Frederick vom Saal and Claude Hughes

A previous report, released by the Harvard Center for Risk Analysis and funded by the American Plastics Council, called the evidence for risks "weak" and "inconsistent".

References

  • Dianin, Zhurnal russkogo fiziko-khimicheskogo obshchestva, 23 (1891), pp. 492 ff.
  • Mittheilungen aus dem chemischen Laboratorium der Universität Marburg, T. Zincke, Justus Leibigs Annals Chemie, 343 (1905), pp. 75-99.

External Links

"Study Cites Risk of Compound in Plastic Bottles" - LA Times

Plastics Industry Bisphenol A information site

Bisphenol Info page of a site about dangers of endocrine disruptors

EPA page on Bisphenol A

An Endocrine/Estrogen Letter special Report on BPA