4-Methylbenzylidene camphor 5196620 213011768 2008-05-17T09:54:52Z Stone 13976 <!-- Here is a table of data; skip past it to edit the text. --> <!-- Submit {{:subst:chembox_simple_organic}} to get this template or go to [[:Template:Chembox simple organic]]. --> {| border="1" cellpadding="2" cellspacing="0" align="right" style="margin-left:1em; background: #ffffff;" ! colspan="2" align=center bgcolor="#cccccc" | '''4-MBC''' |- | colspan="2" align=center | [[Image: 4-Methylbenzylidene camphor.svg|200px|{{PAGENAME}}]] |- | [[IUPAC nomenclature|Chemical name]] | 4-Methylbenzylidene camphor (4-MBC) |- | [[Chemical formula]] | C<sub>18</sub>H<sub>22</sub>O<sub></sub> |- | [[Molecular mass]] | 254.4 |- | [[Melting point]] | 66-70°C |- | [[Boiling point]] | |- | [[Density]] | |- | [[CAS registry number|CAS number]] | 36861-47-9 |- | [[Simplified molecular input line entry specification|SMILES]] | <small> </small> |- |} '''4-Methylbenzylidene camphor''', short '''4-MBC''', also '''3-(4-Methylbenzylidene)bornan-2-one''', or '''3-(4-Methylbenzylidene)-dl-camphor''' is an organic [[camphor]] derivative that is used in the [[Cosmetics|cosmetic]] industry for its ability to protect the [[skin]] against [[UV]], specifically UV B radiation. As such it is used in [[sunscreen]] [[lotion]]s and [[deodorant]]s. Its tradenames include '''Eusolex 6300''' ([[Merck & Co.|Merck]]) and '''Parsol 5000''' ([[DSM (company)|DSM]]). ==Mechanism== All the camphor sunscreens are supposed to dissipate the photon energy by trans-cis isomerisation. But for Parsol 5000 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.<ref>''Sun Protection in Man''. Chapter 26: Cantrell, Ann; McGarvey, David J.; Truscott, T. George. Photochemical and photophysical properties of sunscreens.</ref> ==Endocrine disruptor== Studies have raised the issue that 4-MBC acts an [[endocrine disruptor]]. There is controversy about the [[estrogen]]ic effects of 4-MBC and while one study showed only a relatively minor effect<ref>[http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12765243&dopt=Abstract] Low estrogenic activity</ref>, a study in Switzerland showed significant uterine growth in immature rodents.<ref>[http://www.mindfully.org/Health/Sun-Screens-EDs.htm] Significant estrogenic activity</ref> In addition, there is some evidence that 4-MBC may suppress the pituitary-thyroid axis leading to [[hypothyroidism]].<ref>[http://www.endocrine-abstracts.org/ea/0011/ea0011oc60.htm] Inhibition of pit-thyroid axis</ref> The agent can also lead to a [[photoallergy|photoallergic]] [[dermatitis]]. ==Approval status== 4-MBC is approved for use in Europe by the [[European Union]]'s Scientific Committee for Cosmetic Products & Non-Food Products but is not approved for use in the USA by the [[Food and Drug Administration]]. It is also approved in Canada by [[Health Canada]], in Australia and other countries. It's not permitted in Japan. ==Alternative agents== Alternative agents that block UV by [[Absorption (skin)|absorption]] include: * [[Avobenzone]] * [[Oxybenzone]] * [[octyl methoxycinnamate]] (OMC) * [[homosalate]] ==See also== [[Xenoestrogen]] ==References== <references/> ==External links== * [http://www.greentox.org/ Reports of endocrine disruption] * [http://www.chemicalland21.com/specialtychem/finechem/3-(4-METHYLBENZYLIDEN)CAMPHOR.htm Chemical information] [[Category:Dermatological preparations]] [[Category:Sunscreening agents]]