4-Methylbenzylidene camphor

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4-Methylbenzylidene camphor[1]
Skeletal formula of 4-methylbenzylidene camphor
Ball-and-stick model of the 4-methylbenzylidene camphor molecule
Names
IUPAC name
(3E)-1,7,7-Trimethyl-3-[(4-methylphenyl)methylene]-2-norbornanone
Other names
Enzacamene; 3-(4-Methylbenzylidene)bornan-2-one
3-(4-Methylbenzylidene)-dl-camphor
Identifiers
36861-47-9 N
Abbreviations 4-MBC
ChemSpider 4939160 YesY
EC Number 253-242-6
Jmol 3D model Interactive image
PubChem 6434217
Properties
C18H22O
Molar mass 254.37 g/mol
Appearance White crystalline powder
Melting point 66 to 69 °C (151 to 156 °F; 339 to 342 K)
Insoluble
Hazards
Main hazards Xi
R-phrases R36/37/38 R50 R53
S-phrases S26 S37/39 S61
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YesYN ?)
Infobox references

4-Methylbenzylidene camphor (4-MBC, enzacamene) is an organic camphor derivative that is used in the cosmetic industry for its ability to protect the skin against UV, specifically UV B radiation. As such it is used in sunscreen lotions and other skincare products claiming a SPF value. Its tradenames include Eusolex 6300 (Merck) and Parsol 5000 (DSM).

Mechanism[edit]

All the camphor sunscreens are supposed to dissipate the photon energy by cis-trans isomerisation. But for 4-MBC the quantum yield for this isomerisation is reported to be only between 0.13 - 0.3. This low quantum yield means that other photochemical processes are occurring.[2]

Endocrine disruptor[edit]

Studies have raised the issue that 4-MBC acts an endocrine disruptor. There is controversy about the estrogenic effects of 4-MBC and while one study showed only a relatively minor effect,[3] a study in Switzerland showed significant uterine growth in immature rodents.[4] In addition, there is some evidence that 4-MBC may suppress the pituitary-thyroid axis leading to hypothyroidism.[5]

The agent can also lead to a photoallergic dermatitis.[citation needed]

Approval status[edit]

4-MBC has been banned for use in Europe by the European Union since 2015.[6] It is approved in Canada by Health Canada. It is not approved for use in the USA by the Food and Drug Administration and it is not permitted in Japan.

See also[edit]

References[edit]

  1. ^ 3-(4-METHYLBENZYLIDEN)CAMPHOR at chemicalland21.com
  2. ^ Sun Protection in Man. Chapter 26: Cantrell, Ann; McGarvey, David J.; Truscott, T. George. Photochemical and photophysical properties of sunscreens.
  3. ^ Mueller SO; Kling M; Arifin Firzani P; et al. (April 2003). "Activation of estrogen receptor alpha and ERbeta by 4-methylbenzylidene-camphor in human and rat cells: comparison with phyto- and xenoestrogens". Toxicol. Lett. 142 (1-2): 89–101. doi:10.1016/S0378-4274(03)00016-X. PMID 12765243. 
  4. ^ Sun Block has Endocrine Disruptor Chemicals, New Scientist, April 18, 2001
  5. ^ IH Hamann; C Schmutzler; P Kirschmeyer; H Jarry & J Köhrle (2006). "4-Methylbenzylidene-camphor (4MBC) causes pituitary effects comparable to hypothyroidism". Endocrine Abstracts 11: OC60. 
  6. ^ http://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:32015R1298&from=EN