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| | colspan=2 | References: <sup id="fn_3_back">]]</sup> | |||
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| </div> | </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 |
'''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 ]. | ||
| ==History== | |||
| 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. | |||
| Bisphenol A was first synthesized by Dianin in 1891<sup id="fn_1_back">]]</sup>,<sup id="fn_2_back">]]</sup>. Bisphenol A was investigated in the 1930s during the search for synthetic ]. At that time, another synthesized compound, ], turned out to be more powerful an estrogen, so bisphenol A was not used as a synthetic estrogen. Its current main uses are as a ] in the manufacture of ] ] and in the manufacture of ] resins. Bisphenol A is also used as an antioxidant in ], as an ] in ], and as a ] inhibitor in ]. | |||
| ⚫ | Polycarbonates are widely used in |
||
| ⚫ | Polycarbonates are widely used in many 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 == | ||
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| 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. | ||
| The first evidence of bisphenol A's estrogenicity came from experiments in the |
The first evidence of bisphenol A's estrogenicity came from experiments in the 1930s in which it was fed to ovariectomised rats<sup id="fn_4_back">]]</sup>,<sup id="fn_5_back">]]</sup>. Some ] 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). It has been claimed that these effects lead to health problems such as, in men, lowered ] count and infertile sperm. | ||
| 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 ] and ]<sup>] | 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 ] and ]<sup>]</sup>. 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== | ==References== | ||
| * Dianin, ''Zhurnal russkogo fiziko-khimicheskogo obshchestva'', 23 (1891), pp. 492 ff. | * <cite id="fn_1">]</cite> Dianin, ''Zhurnal russkogo fiziko-khimicheskogo obshchestva'', 23 (1891), pp. 492 ff. | ||
| ⚫ | * <cite id="fn_2">]</cite> Th. Zincke, Mittheilungen aus dem chemischen Laboratorium der Universität Marburg, ''Justus Liebigs Annalen der Chemie'', 343 (1905), pp. 75-131. | ||
| ⚫ | * <cite id="fn_3">]</cite> ''Handbook of Chemistry and Physics'', CRC Press, 76th edition (1995-1996). | ||
| * <cite id="fn_4">]</cite> E. C. Dodds and Wilfrid Lawson, ''Nature'', 137 (1936), 996. | |||
| ⚫ | * Mittheilungen aus dem chemischen Laboratorium der Universität Marburg |
||
| * <cite id="fn_5">]</cite> E. C. Dodds and W. Lawson, ''Proceedings of the Royal Society of London, Series B, Biological Sciences'', 125, #839 (27-IV-1938), pp. 222-232. | |||
| ⚫ | * ''Handbook of Chemistry and Physics'', CRC Press, 76th edition (1995-1996). | ||
| ==External Links== | ==External Links== | ||
| * 6: | |||
| * | |||
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Revision as of 22:41, 17 May 2005
| Bisphenol A | |
|---|---|
| Chemical name | 4,4'-(propan-2-ylidene)diphenol 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 |
| References: | |
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.
History
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 an estrogen, so bisphenol A was not used as a synthetic estrogen. Its current main uses are as a monomer in the manufacture of polycarbonate plastic and in the manufacture of epoxy resins. Bisphenol A is also used as an antioxidant in plasticizers, as an antioxidant in PVC, and as a polymerization inhibitor in PVC.
Polycarbonates are widely used in many 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 1930s in which it was fed to ovariectomised rats,. 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). It has been claimed that these effects lead to health problems such as, in men, lowered sperm count and infertile sperm.
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
- 1: Dianin, Zhurnal russkogo fiziko-khimicheskogo obshchestva, 23 (1891), pp. 492 ff.
- 2: Th. Zincke, Mittheilungen aus dem chemischen Laboratorium der Universität Marburg, Justus Liebigs Annalen der Chemie, 343 (1905), pp. 75-131.
- 3: Handbook of Chemistry and Physics, CRC Press, 76th edition (1995-1996).
- 4: E. C. Dodds and Wilfrid Lawson, Nature, 137 (1936), 996.
- 5: E. C. Dodds and W. Lawson, Proceedings of the Royal Society of London, Series B, Biological Sciences, 125, #839 (27-IV-1938), pp. 222-232.