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{{Short description|Vitamin}}
{{cs1 config|name-list-style=vanc}}
{{lowercasetitle}}
{{Use mdy dates|date=February 2024}}
{{chembox
{{chembox
| Name = α-Tocopheryl acetate
| verifiedrevid = 470611314
| verifiedrevid = 470611314
| ImageFile1 = Tocopheryl acetate.png
| ImageFile1 = Tocopheryl acetate.png
| ImageAlt1 = RRR-α-Tocopheryl acetate
| ImageFile2= Tocopheryl_acetate_3d_structure.png
| ImageFile2= Tocopheryl_acetate_3d_structure.png
| ImageAlt2 = RRR-α-Tocopheryl acetate
| IUPACName = [(2''R'')-2,5,7,8-Tetramethyl-2-[(4''R'',8''R'')-4,8,12-trimethyltridecyl]chroman-6-yl] acetate
| PIN = (2''R'')-2,5,7,8-Tetramethyl-2-[(4''R'',8''R'')-4,8,12-trimethyltridecyl]-3,4-dihydro-2''H''-1-benzopyran-6-yl acetate
| OtherNames = Tocopherol acetate <br>Vitamin E acetate
| OtherNames = α-Tocopherol acetate<br>Vitamin E acetate
|Section1={{Chembox Identifiers
|Section1={{Chembox Identifiers
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
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| StdInChIKey = ZAKOWWREFLAJOT-CEFNRUSXSA-N
| StdInChIKey = ZAKOWWREFLAJOT-CEFNRUSXSA-N
| CASNo = 58-95-7
| CASNo = 58-95-7
| CASNo_Comment =RRR-α-isomer
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo_Ref = {{cascite|correct|CAS}}
| PubChem = 86472
| PubChem = 86472
| DrugBank = DB14003
| SMILES = O=C(Oc2c(c(c1O[C@](CCc1c2C)(C)CCC[C@H](C)CCC[C@H](C)CCCC(C)C)C)C)C
| SMILES = O=C(Oc2c(c(c1O[C@](CCc1c2C)(C)CCC[C@H](C)CCC[C@H](C)CCCC(C)C)C)C)C
}}
}}
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| Formula = C<sub>31</sub>H<sub>52</sub>O<sub>3</sub>
| Formula = C<sub>31</sub>H<sub>52</sub>O<sub>3</sub>
| MolarMass = 472.743 g/mol
| MolarMass = 472.743 g/mol
| Appearance =
| Appearance =pale yellow, viscous liquid<ref name=m/>
| Density =
| Density =
| MeltingPt =
| MeltingPt =–27.5 °C
| MeltingPt_ref =<ref name=m/>
| BoilingPt =
| Solubility =
| BoilingPt =240 °C
| BoilingPt_notes =decays without boiling<ref name=eu/>
| Solubility =insoluble<ref name=m/>
| SolubleOther =soluble in [[acetone]], [[chloroform]], [[diethyl ether]]; poorly soluble in [[ethanol]]<ref name=m/>
}}
}}
|Section3={{Chembox Hazards
|Section3={{Chembox Hazards
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| NFPA-F = 1
| NFPA-F = 1
| NFPA-R = 0
| NFPA-R = 0
| MainHazards =
| MainHazards =
| FlashPt =
| FlashPt =
| AutoignitionPt =
| AutoignitionPt =
}}
}}
}}
}}
'''α-Tocopheryl acetate''' ('''''alpha''-tocopherol acetate'''), also known as '''vitamin E acetate''', is a form of [[vitamin E]] with D-Alpha Tocopheryl Acetate as the natural form and DL-Alpha Tocopheryl Acetate as the synthetic form. DL-indicates the synthetic form where as D- indicates the natural form. It is the [[ester]] of [[acetic acid]] and {{nowrap|[[α-tocopherol]]}}.<ref name=eu/>


The [[U.S. Centers for Disease Control and Prevention]] says that vitamin E acetate is a very strong culprit of concern in the [[2019–20 vaping lung illness outbreak|2019 outbreak]] of [[vaping-associated pulmonary injury]] (VAPI),<ref name=CDC----2019/> but there is not yet sufficient evidence to rule out contributions from other chemicals.<ref>{{cite journal|last1=Feldman|first1=Ryan|last2=Meiman|first2=Jonathan|last3=Stanton|first3=Matthew|last4=Gummin|first4=David D.|date=June 2020|title=Culprit or correlate? An application of the Bradford Hill criteria to Vitamin E acetate|journal=Archives of Toxicology|volume=94|issue=6|pages=2249–2254|doi=10.1007/s00204-020-02770-x|issn=1432-0738|pmid=32451600|s2cid=218878143}}</ref><ref name=CDC2019/> Vaporization of this ester produces toxic [[pyrolysis]] products.<ref name=pmid32156732/>
⚫
'''Tocopheryl acetate''', also known as '''vitamin E acetate''', is a common vitamin supplement with the molecular formula C<sub>31</sub>H<sub>52</sub>O<sub>3</sub> (for 'α' form). It is the [[ester]] of [[acetic acid]] and [[tocopherol]] ([[vitamin E]]). It is often used in [[dermatological]] [[Product (business)|products]] such as skin creams. Tocopheryl acetate is not oxidized and can penetrate through the skin to the living cells, where about 5% is converted to free tocopherol. Claims are made for beneficial antioxidant effects.<ref>{{webarchive |url=https://web.archive.org/web/20150223105720id_/http://lpi.oregonstate.edu/fw04/allaboute.html|title=Linus Pauling Institute Research Report: All About E }}</ref> Tocopheryl acetate is used as an alternative to tocopherol itself because the [[phenol]]ic [[hydroxyl group]] is blocked, providing a less acidic product with a longer shelf life. It is believed that the acetate is slowly [[hydrolysis|hydrolyzed]] after it is absorbed into the skin, regenerating tocopherol and providing protection against the sun's [[ultraviolet]] rays.<ref>{{cite journal |vauthors=Beijersbergen van Henegouwen G, Junginger H, de Vries H |title=Hydrolysis of RRR-alpha-tocopheryl acetate (vitamin E acetate) in the skin and its UV protecting activity (an in vivo study with the rat) |journal=J Photochem Photobiol B |volume=29 |issue=1 |pages=45–51 |year=1995 |pmid=7472802 |doi=10.1016/1011-1344(95)90251-1}}</ref> Tocopheryl acetate was first synthesized in 1963 by workers at [[Hoffmann-La Roche]].<ref name="MayerSchudel1963">{{cite journal|last1=Mayer|first1=H.|last2=Schudel|first2=P.|last3=Rüegg|first3=R.|last4=Isler|first4=O.|title=Über die Chemie des Vitamins E. 3. Mitteilung. Die Totalsynthese von (2R, 4′R, 8′R)- und (2S, 4′R, 8′R)-α-Tocopherol|journal=Helvetica Chimica Acta|volume=46|issue=2|year=1963|pages=650–671|issn=0018019X|doi=10.1002/hlca.19630460225}}</ref>


==Use in cosmetics==
⚫
Although there is widespread use of tocopheryl acetate as a [[topical medication]], with claims for improved [[wound healing]] and reduced [[scar]] tissue,<ref>{{cite journal |vauthors=Panin G, Strumia R, Ursini F |title=Topical alpha-tocopherol acetate in the bulk phase: eight years of experience in skin treatment |journal=Ann. N. Y. Acad. Sci. |volume=1031 |issue= |pages=443–447 |date=2004 |pmid=15753192 |doi=10.1196/annals.1331.069 |url=|bibcode=2004NYASA1031..443P }}</ref> reviews have repeatedly concluded that there is insufficient evidence to support these claims.<ref>{{cite journal |vauthors=Sidgwick GP, McGeorge D, Bayat A |title=A comprehensive evidence-based review on the role of topicals and dressings in the management of skin scarring |journal=Arch. Dermatol. Res. |volume=307 |issue=6 |pages=461–477 |year=2015 |pmid=26044054 |pmc=4506744 |doi=10.1007/s00403-015-1572-0 |url=}}</ref><ref>{{cite journal |vauthors=Tanaydin V, Conings J, Malyar M, van der Hulst R, van der Lei B |title=The Role of Topical Vitamin E in Scar Management: A Systematic Review |journal=Aesthet Surg J |volume=36 |issue=8 |pages=959–965 |date=2016 |pmid=26977069 |doi=10.1093/asj/sjw046 |url=}}</ref> There are reports of vitamin E-induced allergic contact dermatitis from use of vitamin-E derivatives such as [[tocopheryl linoleate]] and tocopherol acetate in skin care products. Incidence is low despite widespread use.<ref>{{cite journal |vauthors=Kosari P, Alikhan A, Sockolov M, Feldman SR |title=Vitamin E and allergic contact dermatitis |journal=Dermatitis |volume=21 |issue=3 |pages=148–153 |date=2010 |pmid=20487657 |doi= |url=}}</ref>
⚫
α-Tocopheryl acetate is often used in [[dermatological]] [[Product (business)|products]] such as skin creams. It is not oxidized and can penetrate through the skin to the living cells, where about 5% is converted to free [[tocopherol]]. Claims are made for beneficial antioxidant effects.<ref>{{webarchive |url=https://web.archive.org/web/20150223105720/http://lpi.oregonstate.edu/fw04/allaboute.html|date=February 23, 2015|title=Linus Pauling Institute Research Report: All About E }}</ref> α-Tocopheryl acetate is used as an alternative to tocopherol itself because the [[phenol]]ic [[hydroxyl group]] is blocked, providing a less acidic product with a longer shelf life. It is believed that the acetate is slowly [[hydrolysis|hydrolyzed]] after it is absorbed into the skin, regenerating tocopherol and providing protection against the sun's [[ultraviolet]] rays.<ref>{{cite journal |vauthors=Beijersbergen van Henegouwen G, Junginger H, de Vries H |title=Hydrolysis of RRR-alpha-tocopheryl acetate (vitamin E acetate) in the skin and its UV protecting activity (an in vivo study with the rat) |journal=J Photochem Photobiol B |volume=29 |issue=1 |pages=45–51 |year=1995 |pmid=7472802 |doi=10.1016/1011-1344(95)90251-1}}</ref> Tocopheryl acetate was first synthesized in 1963 by workers at [[Hoffmann-La Roche]].<ref name="MayerSchudel1963">{{cite journal|last1=Mayer|first1=H.|last2=Schudel|first2=P.|last3=Rüegg|first3=R.|last4=Isler|first4=O.|title=Über die Chemie des Vitamins E. 3. Mitteilung. Die Totalsynthese von (2''R'', 4''′R'', 8''′R'')- und (2''S'', 4''′R'', 8''′R'')-α-Tocopherol|journal=Helvetica Chimica Acta|volume=46|issue=2|year=1963|pages=650–671|issn=0018-019X|doi=10.1002/hlca.19630460225}}</ref>


⚫
Although there is widespread use of tocopheryl acetate as a [[topical medication]], with claims for improved [[wound healing]] and reduced [[scar]] tissue,<ref>{{cite journal |vauthors=Panin G, Strumia R, Ursini F |title=Topical alpha-tocopherol acetate in the bulk phase: eight years of experience in skin treatment |journal=Ann. N. Y. Acad. Sci. |volume=1031 |pages=443–447 |date=2004 |issue=1 |pmid=15753192 |doi=10.1196/annals.1331.069 |bibcode=2004NYASA1031..443P |s2cid=45771699 |s2cid-access=free |url=https://images-na.ssl-images-amazon.com/images/I/B2tgqw5FeaS.pdf }}</ref> reviews have repeatedly concluded that there is insufficient evidence to support these claims.<ref>{{cite journal |vauthors=Sidgwick GP, McGeorge D, Bayat A |title=A comprehensive evidence-based review on the role of topicals and dressings in the management of skin scarring |journal=Arch. Dermatol. Res. |volume=307 |issue=6 |pages=461–477 |year=2015 |pmid=26044054 |pmc=4506744 |doi=10.1007/s00403-015-1572-0 |doi-access=free }}</ref><ref>{{cite journal |vauthors=Tanaydin V, Conings J, Malyar M, van der Hulst R, van der Lei B |title=The Role of Topical Vitamin E in Scar Management: A Systematic Review |journal=Aesthet Surg J |volume=36 |issue=8 |pages=959–965 |date=2016 |pmid=26977069 |doi=10.1093/asj/sjw046|doi-access=free }}</ref> There are reports of vitamin E-induced allergic contact dermatitis from use of vitamin E derivatives such as [[tocopheryl linoleate]] and tocopherol acetate in skin care products. Incidence is low despite widespread use.<ref>{{cite journal |vauthors=Kosari P, Alikhan A, Sockolov M, Feldman SR |title=Vitamin E and allergic contact dermatitis |journal=Dermatitis |volume=21 |issue=3 |pages=148–153 |date=2010 |pmid=20487657 |doi=10.2310/6620.2010.09083|s2cid=38212099 }}</ref>
On September 5th, 2019, the United States [[Food and Drug Administration]] (US FDA) announced that 10 out of 18, or 55.56% of the samples of cannabis-containing vape liquids sent in by states, linked to [[2019 United States outbreak of lung illness linked to vaping products|recent vaping related lung disease outbreak in the United States]], tested positive for vitamin E acetate<ref>{{Cite web|url=https://www.washingtonpost.com/health/2019/09/05/contaminant-found-vaping-products-linked-deadly-lung-illnesses-state-federal-labs-show/|title=Contaminant found in marijuana vaping products linked to deadly lung illnesses, tests show|last=Sun|first=Lena|date=September 6, 2019|website=Washington Post|language=en|url-status=live|archive-url=|archive-date=|access-date=2019-09-09}}</ref> which is being used as a thinning agent by some manufacturers.<ref>{{Cite web|url=https://theglobepost.com/2019/09/12/vaping-warning-cdc/|title=Vague Warning to Stop Vaping E-Cigarettes is Incorrect and Irresponsible|date=September 12, 2019|website=The Globe Post|language=en|url-status=live}}</ref> The FDA announced that some state labs have found vitamin E acetate, but stressed that "{{nowrap|[a]t}} this time, no one device, product, or substance has been linked to all cases."<ref>{{Cite web|url=https://www.cdc.gov/media/releases/2019/t0906_telebriefing_investigation_pulmonary_disease_e-cigarettes.html|title=Transcript of September 6, 2019, Telebriefing: Investigation of Pulmonary Disease Among People Who Use E-cigarettes|last=Centers for Disease Control and Prevention|first=|date=September 6, 2019|website=www.cdc.gov|language=en-us|url-status=live|archive-url=|archive-date=|access-date=2019-09-09}}</ref>


==Misuse==
<br />


===Ingredient in vape liquids===
⚫
==References==
{{also|2019–20 vaping lung illness outbreak|Vaping-associated pulmonary injury|Lacing (drugs)#Cannabis}}

On September 5, 2019, the United States [[Food and Drug Administration]] (US FDA) announced that 10 out of 18, or 56% of the samples of vape liquids sent in by states, linked to [[2019–20 vaping lung illness outbreak|the recent vaping-related lung disease outbreak in the United States]], tested positive for vitamin E acetate<ref>{{cite news|url=https://www.washingtonpost.com/health/2019/09/05/contaminant-found-vaping-products-linked-deadly-lung-illnesses-state-federal-labs-show/|title=Contaminant found in marijuana vaping products linked to deadly lung illnesses, tests show|last=Sun|first=Lena|date=September 6, 2019|newspaper=Washington Post|language=en|access-date=September 9, 2019}}</ref> which had been used as a thickening agent by [[black market|illicit]] THC vape cartridge manufacturers.<ref>{{cite magazine|url=https://www.rollingstone.com/culture/culture-features/vaping-honey-cut-mystery-thickener-vitamin-e-acetate-vapes-881896/|title=Three Companies Subpoenaed in Weed Vape Illness Investigation|date=September 10, 2019|magazine=Rolling Stone|language=en}}</ref> On November 8, 2019, the [[Centers for Disease Control and Prevention]] (CDC) identified vitamin E acetate as a very strong culprit of concern in the vaping-related illnesses, but has not ruled out other chemicals or toxicants as possible causes.<ref name=CDC----2019/> The CDC's findings were based on fluid samples from the lungs of 29 patients with [[vaping-associated pulmonary injury]], which provided direct evidence of vitamin E acetate at the primary site of injury in all the 29 lung fluid samples tested.<ref name=CDC----2019>{{cite web|url=https://www.cdc.gov/media/releases/2019/t1108-telebriefing-vaping.html|title=Transcript of CDC Telebriefing: Update on Lung Injury Associated with E-cigarette Use, or Vaping|publisher=Centers for Disease Control and Prevention|date=November 8, 2019}}{{PD-notice}}</ref> Research suggests when vitamin E acetate is inhaled, it may interfere with normal lung functioning.<ref name=CDC2019>{{cite web|url=https://www.cdc.gov/tobacco/basic_information/e-cigarettes/severe-lung-disease.html|title=Outbreak of Lung Injury Associated with E-Cigarette Use, or Vaping|publisher=[[Centers for Disease Control and Prevention]]|date=November 8, 2019}}{{PD-notice}}</ref> A 2020 study found that vaporizing vitamin E acetate produced carcinogenic [[alkenes]] and [[benzene]], but also exceptionally toxic [[ketene]] gas, which may be a contributing factor to the pulmonary injuries.<ref name=pmid32156732>{{cite journal|last1=Wu|first1=D|last2=O'Shea|first2=DF|date=March 24, 2020|title=Potential for release of pulmonary toxic ketene from vaping pyrolysis of vitamin E acetate|journal=Proceedings of the National Academy of Sciences of the United States of America|volume=117|issue=12|pages=6349–6355|doi=10.1073/pnas.1920925117|pmc=7104367|pmid=32156732|doi-access=free|bibcode=2020PNAS..117.6349W}}</ref>

==Chemistry==
At room temperature, α-tocopheryl acetate is a fat-soluble liquid. It has 3 [[chiral centers]] and thus 8 [[stereoisomers]]. It is made by [[ester]]ifying [[α-tocopherol]] with [[acetic acid]]. 2''R'',4''R'',8''R''-isomer, also known as RRR-α-tocopheryl acetate, is the most common isomer used for various purposes. This is because α-tocopherol occurs in nature primarily as RRR-α-tocopherol.<ref name=eu>{{cite journal|date=2016|title=Safety assessment of the substance α-tocopherol acetate for use in food contact materials|journal=EFSA Journal|volume=14|issue=3|pages=4412|doi=10.2903/j.efsa.2016.4412|doi-access=free}}</ref>

α-Tocopherol acetate does not boil at [[atmospheric pressure]] and begins to degrade at 240&nbsp;°C.<ref name=eu/> It can be [[Vacuum distillation|vacuum distilled]]: it boils at 184&nbsp;°C at 0.01&nbsp;[[mmHg]], at 194&nbsp;°C (0.025&nbsp;mmHg) and at 224&nbsp;°C (0.3&nbsp;mmHg). In practice, it is not degraded notably by [[air]], [[visible light]] or [[UV-radiation]]. It has a [[refractive index]] of 1.4950–1.4972 at 20&nbsp;°C.<ref name=m>{{cite book|title=The Merck index|date=1996|publisher=Merck|isbn=9780911910124|edition=12th|pages=1580|display-authors=et al}}</ref>

α-Tocopherol acetate is [[hydrolyzed]] to α-tocopherol and acetic acid under suitable conditions or when ingested by people.<ref name=eu/>

⚫
== References ==
{{Reflist}}
{{Reflist}}


Latest revision as of 15:17, 19 November 2024

α-Tocopheryl acetate
RRR-α-Tocopheryl acetate
RRR-α-Tocopheryl acetate
Names
Preferred IUPAC name
(2R)-2,5,7,8-Tetramethyl-2-[(4R,8R)-4,8,12-trimethyltridecyl]-3,4-dihydro-2H-1-benzopyran-6-yl acetate
Other names
α-Tocopherol acetate
Vitamin E acetate
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.000.369 Edit this at Wikidata
UNII
  • InChI=1S/C31H52O3/c1-21(2)13-10-14-22(3)15-11-16-23(4)17-12-19-31(9)20-18-28-26(7)29(33-27(8)32)24(5)25(6)30(28)34-31/h21-23H,10-20H2,1-9H3/t22-,23-,31-/m1/s1 checkY
    Key: ZAKOWWREFLAJOT-CEFNRUSXSA-N checkY
  • InChI=1/C31H52O3/c1-21(2)13-10-14-22(3)15-11-16-23(4)17-12-19-31(9)20-18-28-26(7)29(33-27(8)32)24(5)25(6)30(28)34-31/h21-23H,10-20H2,1-9H3/t22-,23-,31-/m1/s1
    Key: ZAKOWWREFLAJOT-CEFNRUSXBQ
  • O=C(Oc2c(c(c1O[C@](CCc1c2C)(C)CCC[C@H](C)CCC[C@H](C)CCCC(C)C)C)C)C
Properties
C31H52O3
Molar mass 472.743 g/mol
Appearance pale yellow, viscous liquid[1]
Melting point –27.5 °C[1]
Boiling point 240 °C decays without boiling[2]
insoluble[1]
Solubility soluble in acetone, chloroform, diethyl ether; poorly soluble in ethanol[1]
Hazards
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineFlammability 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g. canola oilInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
1
1
0
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

α-Tocopheryl acetate (alpha-tocopherol acetate), also known as vitamin E acetate, is a form of vitamin E with D-Alpha Tocopheryl Acetate as the natural form and DL-Alpha Tocopheryl Acetate as the synthetic form. DL-indicates the synthetic form where as D- indicates the natural form. It is the ester of acetic acid and α-tocopherol.[2]

The U.S. Centers for Disease Control and Prevention says that vitamin E acetate is a very strong culprit of concern in the 2019 outbreak of vaping-associated pulmonary injury (VAPI),[3] but there is not yet sufficient evidence to rule out contributions from other chemicals.[4][5] Vaporization of this ester produces toxic pyrolysis products.[6]

Use in cosmetics

[edit]

α-Tocopheryl acetate is often used in dermatological products such as skin creams. It is not oxidized and can penetrate through the skin to the living cells, where about 5% is converted to free tocopherol. Claims are made for beneficial antioxidant effects.[7] α-Tocopheryl acetate is used as an alternative to tocopherol itself because the phenolic hydroxyl group is blocked, providing a less acidic product with a longer shelf life. It is believed that the acetate is slowly hydrolyzed after it is absorbed into the skin, regenerating tocopherol and providing protection against the sun's ultraviolet rays.[8] Tocopheryl acetate was first synthesized in 1963 by workers at Hoffmann-La Roche.[9]

Although there is widespread use of tocopheryl acetate as a topical medication, with claims for improved wound healing and reduced scar tissue,[10] reviews have repeatedly concluded that there is insufficient evidence to support these claims.[11][12] There are reports of vitamin E-induced allergic contact dermatitis from use of vitamin E derivatives such as tocopheryl linoleate and tocopherol acetate in skin care products. Incidence is low despite widespread use.[13]

Misuse

[edit]

Ingredient in vape liquids

[edit]
See also: 2019–20 vaping lung illness outbreak, Vaping-associated pulmonary injury, and Lacing (drugs) § Cannabis

On September 5, 2019, the United States Food and Drug Administration (US FDA) announced that 10 out of 18, or 56% of the samples of vape liquids sent in by states, linked to the recent vaping-related lung disease outbreak in the United States, tested positive for vitamin E acetate[14] which had been used as a thickening agent by illicit THC vape cartridge manufacturers.[15] On November 8, 2019, the Centers for Disease Control and Prevention (CDC) identified vitamin E acetate as a very strong culprit of concern in the vaping-related illnesses, but has not ruled out other chemicals or toxicants as possible causes.[3] The CDC's findings were based on fluid samples from the lungs of 29 patients with vaping-associated pulmonary injury, which provided direct evidence of vitamin E acetate at the primary site of injury in all the 29 lung fluid samples tested.[3] Research suggests when vitamin E acetate is inhaled, it may interfere with normal lung functioning.[5] A 2020 study found that vaporizing vitamin E acetate produced carcinogenic alkenes and benzene, but also exceptionally toxic ketene gas, which may be a contributing factor to the pulmonary injuries.[6]

Chemistry

[edit]

At room temperature, α-tocopheryl acetate is a fat-soluble liquid. It has 3 chiral centers and thus 8 stereoisomers. It is made by esterifying α-tocopherol with acetic acid. 2R,4R,8R-isomer, also known as RRR-α-tocopheryl acetate, is the most common isomer used for various purposes. This is because α-tocopherol occurs in nature primarily as RRR-α-tocopherol.[2]

α-Tocopherol acetate does not boil at atmospheric pressure and begins to degrade at 240 °C.[2] It can be vacuum distilled: it boils at 184 °C at 0.01 mmHg, at 194 °C (0.025 mmHg) and at 224 °C (0.3 mmHg). In practice, it is not degraded notably by air, visible light or UV-radiation. It has a refractive index of 1.4950–1.4972 at 20 °C.[1]

α-Tocopherol acetate is hydrolyzed to α-tocopherol and acetic acid under suitable conditions or when ingested by people.[2]

References

[edit]
  1. ^ a b c d e The Merck index (12th ed.). Merck. 1996. p. 1580. ISBN 9780911910124.
  2. ^ a b c d e "Safety assessment of the substance α-tocopherol acetate for use in food contact materials". EFSA Journal. 14 (3): 4412. 2016. doi:10.2903/j.efsa.2016.4412.
  3. ^ a b c "Transcript of CDC Telebriefing: Update on Lung Injury Associated with E-cigarette Use, or Vaping". Centers for Disease Control and Prevention. November 8, 2019.Public Domain This article incorporates text from this source, which is in the public domain.
  4. ^ Feldman R, Meiman J, Stanton M, Gummin DD (June 2020). "Culprit or correlate? An application of the Bradford Hill criteria to Vitamin E acetate". Archives of Toxicology. 94 (6): 2249–2254. doi:10.1007/s00204-020-02770-x. ISSN 1432-0738. PMID 32451600. S2CID 218878143.
  5. ^ a b "Outbreak of Lung Injury Associated with E-Cigarette Use, or Vaping". Centers for Disease Control and Prevention. November 8, 2019.Public Domain This article incorporates text from this source, which is in the public domain.
  6. ^ a b Wu D, O'Shea DF (March 24, 2020). "Potential for release of pulmonary toxic ketene from vaping pyrolysis of vitamin E acetate". Proceedings of the National Academy of Sciences of the United States of America. 117 (12): 6349–6355. Bibcode:2020PNAS..117.6349W. doi:10.1073/pnas.1920925117. PMC 7104367. PMID 32156732.
  7. ^ Linus Pauling Institute Research Report: All About E at the Wayback Machine (archived February 23, 2015)
  8. ^ Beijersbergen van Henegouwen G, Junginger H, de Vries H (1995). "Hydrolysis of RRR-alpha-tocopheryl acetate (vitamin E acetate) in the skin and its UV protecting activity (an in vivo study with the rat)". J Photochem Photobiol B. 29 (1): 45–51. doi:10.1016/1011-1344(95)90251-1. PMID 7472802.
  9. ^ Mayer H, Schudel P, Rüegg R, Isler O (1963). "Über die Chemie des Vitamins E. 3. Mitteilung. Die Totalsynthese von (2R, 4′R, 8′R)- und (2S, 4′R, 8′R)-α-Tocopherol". Helvetica Chimica Acta. 46 (2): 650–671. doi:10.1002/hlca.19630460225. ISSN 0018-019X.
  10. ^ Panin G, Strumia R, Ursini F (2004). "Topical alpha-tocopherol acetate in the bulk phase: eight years of experience in skin treatment" (PDF). Ann. N. Y. Acad. Sci. 1031 (1): 443–447. Bibcode:2004NYASA1031..443P. doi:10.1196/annals.1331.069. PMID 15753192. S2CID 45771699.
  11. ^ Sidgwick GP, McGeorge D, Bayat A (2015). "A comprehensive evidence-based review on the role of topicals and dressings in the management of skin scarring". Arch. Dermatol. Res. 307 (6): 461–477. doi:10.1007/s00403-015-1572-0. PMC 4506744. PMID 26044054.
  12. ^ Tanaydin V, Conings J, Malyar M, van der Hulst R, van der Lei B (2016). "The Role of Topical Vitamin E in Scar Management: A Systematic Review". Aesthet Surg J. 36 (8): 959–965. doi:10.1093/asj/sjw046. PMID 26977069.
  13. ^ Kosari P, Alikhan A, Sockolov M, Feldman SR (2010). "Vitamin E and allergic contact dermatitis". Dermatitis. 21 (3): 148–153. doi:10.2310/6620.2010.09083. PMID 20487657. S2CID 38212099.
  14. ^ Sun L (September 6, 2019). "Contaminant found in marijuana vaping products linked to deadly lung illnesses, tests show". Washington Post. Retrieved September 9, 2019.
  15. ^ "Three Companies Subpoenaed in Weed Vape Illness Investigation". Rolling Stone. September 10, 2019.
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