August 28, 2008
Why American Readers should read the previous post!
I realize that the previous post is very long and may appear to apply only to Europe, but it is also important to Americans for several reasons:
- American companies who have signed up for the safe cosmetics compact have agreed to follow the European regulations.
- Tony suggests that oakmoss could be considered to not be a "natural" product per the standards that are under development in the US.
- The proposals for the FDA to increase its regulation of cosmetics will probably, if adopted, bring increasing scrutiny to the use of these products in the US.
So read at least the Executive Summary, and if you can go further down and read the details.
Sale / use of fragrant lichen commodities to become virtually illegal in Europe?
From the forthcoming Cropwatch Newsletter & by the Cropwatch Team (with considerable help from those who have to remain anonymous).
SCCP Opinion SCCP/1131/07 ‘Opinion on Oakmoss/Treemoss’ adopted at the 15th Plenary Meeting on 15th April 2008 limits the potent sensitisers atranol & chloroatranol to 2ppm in oakmoss & treemoss (and cedarmoss) products. These SCCP proposal limits are currently unachievable by industry, reported elsewhere as being the result of a mistaken manufacturers claim. Further, they contrast with a forthcoming IFRA Purity Standard (shortly to be introduced under the 43rd IFRA Amendment) which proposes an achievable limit of 100ppm for atranol & chloroatranol respectively. The SCCP proposal drives a stake right through the heart of perfumery art, heritage & culture, since fragrant moss (lichen) extracts are the cornerstones of both the chypre & fougère accords, so important throughout the history of perfumery. It remains to be seen whether this SCCP Opinion will be transformed into an EC edict, and therefore whether fragrant moss products have any future in Europe. Once again, the SCCP, with its impractical Opinions, is in danger of putting European aroma companies at a disadvantage in the global marketplace, unless the Commissioner can be persuaded otherwise.
Some contentious regulatory issues, 2008
Many contentious regulatory issues concerning Health & Safety in the EU remain unresolved, causing reactions amongst professionals which range between skepticism to deep despair. Many European citizens reading this Newsletter will have been spending the past 2-3 months battling with EU’s REACH pre-registration obligations, in order that your aroma company remains in business after 1st Dec 2008. No doubt you will have been attempting to use the user un-friendly software for multiple ingredient registrations, which many have found does not work properly and is difficult or impossible for most companies to network. Meanwhile a proposed act of cultural vandalism against the high art, history & culture of fine fragrance, via some regulatory measures which will ban citrus oil usage in cosmetics, is still hanging over the trade in the form of the phototoxic furanocoumarin issue. We can only assume any potential developments on this issue are temporarily held in abeyance whilst Brussels staff holiday-away the summer months. Ironically, recent studies have identified a number of photo-carcinogenic risks associated with several relatively common (non-aromatic) cosmetic ingredients,; & it will be interesting to see if these findings are quietly ignored by the Commission in favour of continuing to pursue the existing vendetta against natural aromatic products. A similar situation of unfair ingredient hounding applies to the ubiquitous monoterpene constituent and major component of citrus oils, limonene, allegedly a danger to the environment, and therefore classified as an R50/53 material (& also as an R38 irritant & R43 sensitiser). Certain of the more technically adept amongst the regulatory clerks who have been working on limonene’s predicament have appealed to Cropwatch for help to overcome the enveloping regulatory madness surrounding this material, whereby a set of archaic chemical tests (which bear no relation to limonene’s eventual environmental fate) are used to determine its environmental risk classification. Limonene-containing citrus oils have traditionally been used in many types of perfumes (for example, air fresheners, wicks & gels) for their diffusion, lift & character, but perfumers find it difficult or impossible to use them at useful levels because of obligatory R50/53 labeling (who’s labeling incidentally depicts a dead tree, although we challenge anyone to identify any tree killed by limonene). The same situation arguably also extends to pine oils and many other naturals. There is also a knock-on effect with the various eco-labeling systems - which are supposed to represent a form of environmental performance labeling. - since to qualify, fragrances would have to be completely free of ingredients with a R50/53 or R51/53 ’s risk classification. This results in a situation where a good proportion of individual natural ingredients are unable to be used, so that many eco-labeled perfumes are in fact 100% synthetic – possibly the opposite to what customers would expect from this form of labeling..
Meanwhile, we natural ingredient users have another piece of toxicological scare-mongering looming up at us, which is making some parts of the aroma producing industry very, very annoyed, whilst the professional perfumers amongst us wring our hands. This time the ‘anti-fragrance brigade’ is trying to completely strangle the use of fragrant lichen products in cosmetics, via a misconceived 2008 SCCP Opinion.
Oakmoss: importance in perfumery.
Oakmoss products have a solidly established place in perfumery, being the cornerstone of two renowned accords; the chypre and the fougère. In the classical chypre accord, oakmoss is blended with patchouli, labdanum and other woody animalic and ambery notes, and also often with bergamot. These combinations are the foundation of a family of several leading fine fragrances: Chypre (Coty 1917), Mitsouko (Guerlain 1919), Miss Dior (Christian Dior 1919), Ysatis (Givenchy 1984) & in the male category Aramis (Aramis 1965) & Macassar (Rochas 1980) to name but a few. In the fougère accord, striking examples of which include Fougère Royal (Houbigant 1882), Drakkar Noir (Guy Laroche 1982), and Jazz (Yves St. Laurent 1998), oakmoss is blended with coumarin, lavandaceous notes and often with salicylates. Oakmoss products also find uses in colognes, pine fragrances, Crepe de Chine, oriental and fantasy bases etc. etc. (Burfield 2000).
The importance of oakmoss in our perfumery heritage cannot be understated - indeed what are we left with if fragrant moss products are taken away (as nitro-musks and oakmoss have been, in Guerlain’s controversially reformulated Mitsouko fragrance, now a shadow of its former self). Well, we are left with a few synthetic oakmoss chemicals, such as Evernyl (methyl 2-4-dihydroxy-3-6-dimethylbenzoate) and formerly, the less popularly-utilised Orcinyl-3 (3-methoxy-5-methylphenol), which the hype from synthetic aroma chemical producers would try to persuade you ‘represent the essential character compound of oakmoss’. But, as any practicing perfumer will tell you, there is no way that any single oakmoss synthetic can offer the richness, full body and presence of authentic oakmoss commodities in use, nor approach their superior fixative properties, nor can they duplicate approach the way that oakmoss can radiate and resonate through the entire body of a fragrance. It should also be mentioned that a range of commercial oakmoss products exists, some offering a warm, leathery-mossy character, whilst others offer have woody, mossy - almost marine-like aspects. When materials like oakmoss extracts are restricted by the existing culture of toxicological imperialism on dubious safety grounds (and this applies also to other vital perfume ingredients such as coumarin and citrus oils - see elsewhere), the ‘art of the possible’ in perfumery’ dies back even further, with a result that fragrance companies, instead of vigorously opposing regulatory change, end-up producing cheap, conformist and essentially poor-quality perfumes with little consumer re-purchase potential, for a increasingly non-discerning market slot.
It is also important to remember, as Joulain (2002) pointed out, that many in the US did not distinguish botanically between the lichen sources of oakmoss (Evernia prunastri (L.) Arch), and the source for treemoss & cedarwood (Pseudevernia furfuracea (Fr.). This may account for the confusion on various perfume blog sites which have discussed the exact identity of the listed fragrant lichen ingredients employed in a number of classic fragrances, although, to be fair, it should also be remembered that previously oakmoss extracts have invariably been extended with synthetics, and mixed in with treemoss extracts either intentionally, or unintentionally when harvested together..
Cedarmoss growing on Cedrus atlantica in High Atlas, Morocco.
Picture: T. Burfield
Oakmoss products have been identified amongst the most frequent fragrance contact sensitizers (Schnuch et al. 2007), although the exact chemical identity of the major allergens has been elusive. Gonçalo (1988) for example, considered that that the major sensitisers in oakmoss included atranorin, followed by usnic, evernic and fumarprotocetraric
acids, but Bernard et al. (2003) note that sensitivity to oakmoss has been associated with components which hold the phenylbenzoate molecular fragment in common, including atranorin & evernic acid. In particular, Bernard et al. identified atranol & chloroatranol as strong elicitants in most patients sensitized to oakmoss, and that the oakmoss character compound methyl b-orcinol carboxylate (Evernyl) is also capable of eliciting a reaction in most patients.
How widespread is our exposure to atranorin and other lichen sensitizers? Atraric acid, produced by the hydrolysis of atranorin, has been found in low concentrations of the heartwood from oak species Quercus robur & Quercus petraea used for staves in the production of oak barrels used for storage of wine & sprits (Bourgeois et al. 1999). It is likely that colonizing species such as Parmelia olivetorum and/or P. perlata produce depsides in the wood leading to atranorin accumulation.
It is also worth mentioning, as many of the more traveled amongst you will know, that according to some estimations, up to 1,000 tons/year of Parmelia nepalensis (Taylor) Hale ex Sipman is processed into lichen oil, absolute or extract in Western Nepal, and exported for global perfumery and incense use (although the lichens are also used in traditional systems of medicine). Other species such as Parmelia tinctorum Delise ex Nyl. & Usnea spp. may be co-gathered at the point of harvesting. Moxham (1986) notes the use of Parmelia nepalensis, P. nilgherrensis, Ramalina subcomplanata & Usnea lucea in India. Kumar & Muller (1999) have identified the depsides atranorin & diffractaic acid in Parmelia nepalensis & Parmelia tinctorum extracts. (N.B. note that Parmelia furfuracea is a synonym for Pseudervenia furfuracea).
A brief regulatory history of fragrant lichen products
1. An IFRA Standard was introduced for oakmoss extracts in April 1991; the updated IFRA Standard (2001) limits oakmoss extracts to 0.1.% concentration for finished cosmetic products either left on or washed off the skin, but if oakmoss products are also present in the preparation, the combination of both must not exceed 0.1%. As the presence of resin acids seem to be unavoidable in oakmoss products, IFRA `also imposes an interim limit of 0.1%`dehydroabietic acid for oakmoss extracts.
[The forthcoming 43rd IFRA Amendment (2008) will introduce a QRA-based system of concentration limits for oakmoss extracts across 33 different fragrance product categories. Purity criteria for oakmoss products are also introduced in the 43rd IFRA Amendment in the form of limitations on the concentrations of the strong sensitizers, atranol & chloroatranol to 100ppm each].
2. The existing IFRA Standard (1991, 2001) limits treemoss extracts to 0.1.% concentration for finished cosmetic products either left on or washed off the skin, but if oakmoss products are also present in the preparation, the combination of both must not exceed 0.1%. The IFRA Standard limits dehydroabietic acid (DHA) to 0.8% in treemoss extracts as a marker of 2% of total resin acids, determined by a routine analytical method using HPLC Reverse Phase -Spectrofluorimetry method apparently available from IFRA, according to their website.
[The forthcoming 43rd IFRA Amendment (2008) will introduce a QRA-based system of concentration limits for treemoss extracts across 33 different fragranced product categories].
3. Under the 5th EC Framework Program. the EC launched a Quality of Life Initiative & Management of Living Resources key action (1999) which included a study of “Fragrance chemical allergy: a major environmental and consumer health problem in Europe” Contract No: QLK4-CT-1999-01558 (copy available from Cropwatch in case of difficulty locating it). This project led by J..P Leppoittevin employed a number of leading institutions & scientists in the field, including I.R. White (chairman of SCCP) & S.C. Rastogi (member of SCCP). This project completed in March 2003 at total cost of cost of 1, 927,280 Euros; the major part found by the EU. The project included the development and validation of a method for the identification of sensitisers in complex mixtures using the model of oak moss.
4 The SCC(NF)P at its 14th plenary meeting (24 October 2000) accepted an Opinion (SCCNFP/0421/00) concerning Oakmoss/Treemoss, that "… oakmoss/treemoss extracts, present in cosmetic products, have a well-recognised potential to cause allergic reactions in the consumer as fragrance ingredients…" The Opinion can be seen in full at http://ec.europa.eu/health/ph_risk/committees/sccp/docshtml/sccp_out124_en.htm
5. A scientific paper identifying atranol & chloroatranol as strong elicitants in most patients sensitized to oakmoss was released by Bernard et al. (2003). Methyl b-orcinol carboxylate (= Evernyl or methyl atrarate), a
principle odourant of oakmoss absolute, was also identified as an elicitant in most oakmoss sensitized patients. One of the paper’s authors (S.C. Rastogi) is an SCCP committee member.
6. A scientific paper by Bossi et al. (2003) describes the analysis of atranols in perfumes, employing LC-MS-MS with electrospray ionization (ESI) in negative mode One of the authors (S.C. Rastogi) is an SCCP committee member.
7. A scientific paper Rastogi et al. (2004) describing the analysis of 31 commercial perfume found that half the perfumes, & some eau de toilettes contained significant amounts of atranol & chloroatranol.. The author, S.C. Rastogi, is an SCCP committee member).
8. Filho et al (2004) comment that the present volume of lichen extraction is (ecologically) irreversible given the slow growth of lichen.
9. The SCCP at its 2nd plenary meeting (7 December 2004) accepted an Opinion (SCCP/0847/04) on atranol and chloroatranol present in natural extracts (e.g. oakmoss and treemoss extracts) with the conclusion: “…Chloroatranol was shown to cause elicitation of reactions by repeated open exposure at the ppm level (0.0005%) and at the ppb level on patch testing (50% elicit at 0.000015%.). As chloroatranol and atranol are such potent allergens (and chloroatranol particularly so), they should not be present in cosmetic products." Cropwatch comments: We understand that the robustness of certain parts of the scientific evidence in this Opinion is being queried...
S.C. Rastogi & I.R. White were listed as member & chairman respectively of the above SCCP committee.
10. SCCP Opinion SCCP1131/07 (15th April 2008) describes an achievable reduction of atranol & chloroatranol in oakmoss extracts to <2ppm according to an analysis method (which is not disclosed), by two different preparative methods (details of which are not disclosed either). S.C. Rastogi and I.R. White were listed as member & chairman respectively of the SCCP committee. .Cropwatch comments: Data from LLNA tests is set out in the Opinion which did not show that reduction of atranol & chloroatranol contents in treated (but un-analysed) lichen extracts (of unknown purity) affected the LLNA results. Not withstanding this setback which the SCCP puts down to interlaboratory variation (!), the Opinion calls for a 2ppm limit for atranol & chloratranol in fragrant lichen products which would represent a level 50 times lower than the proposed IFRA Standard in its forthcoming 43rd Amendment. Evidence showing that treemoss & cedarmoss extracts deserve to be treated in a similar manner to oakmoss extracts is lacking, and Joulain (2002) has previously argued that the principal sensitisation risks in treemoss absolute prepared as described in his presentation, may centre around 7-oxo-dehydroabietic acid (from oxidized pine resin), rather than the atranols. The SCCP’s acceptance of claims for achievable atranol & chloroatranol concentrations of <2ppm in treated lichen extracts, via unidentified process(es) from an unidentified source, is typical of the secrecy which pervades the working of Brussels’ committees, and we believe contravenes the existing EU guidelines for transparency. Further, contrary information on this matter has been widely circulated in the trade (e.g. in a perfumery professional members communiqué seen by Cropwatch), which alludes to a mistaken claim made by an unidentified company who directly or indirectly have submitted data to the SCCP. This data, we are lead to believe, initially indicated that the 2ppm limit for atranol & chloratranol was achievable. The company involved however, was reported to have later withdrawn the claim when it realised that this experimental research result was not reproducible in a commercial production scenario. Who knows where the truth in this matter lies, but because of the lack of Brussels transparency, Cropwatch can only assume that the SCCP had already seized upon the 2ppm level finding, and, over-hasty as ever, have wrongly adopted the 2ppm limiting level for each sensitizer in the SCCP/1131/07 ‘Opinion on Oakmoss/Treemoss adopted at the 15th Plenary Meeting on 15th April 2008). If Cropwatch has misunderstood any of the above facts, we can point to the fact that much of the aroma trade has as well. As it is, the situation appears to be a complete shambles.
The Commission is of course not obliged to act on an SCCP Opinion, but as close followers of Brussels affairs will know, finding reverse gear in these situations has proven to be an unlearnt skill, and although they make enough mistakes, we have yet to see the SCCP ‘experts’ actually own up to an error. As it is, the result may end up in the effective banning of fragrant moss usage in European cosmetics, unless industry lobbyists can persuade the Commissioner otherwise. .
Interestingly, the scientific literature is pretty scanty on the details of fragrant lichen processing & chemistry, and for this reason Cropwatch has started a fragrant lichen bibliography, in the Cropwatch Files section of its website at http://www.cropwatch.org/oakmossbib.htm. This file will be continually updated - contributions, suggestions, & corrections should be directed please to firstname.lastname@example.org
Oakmoss absolute (Mousse de chêne), concrete, resinoid etc. are derived from the lichen Evernia prunastri (L.) Arch. (Fam. Usneaceae) which grows mainly on the bark of oak trees, but also to some extent on spruces & pine trees. Nine thousand tons of oakmoss lichen is gathered annually in S. Europe, in France (formerly in the forests around Fontainebleau), as well from Calabria, Bohemia, Morocco, Algeria, and the area of former Yugoslavia & Bulgaria (Burfield 2000); however this figure may be overstated – Joulain (2002) mentions a figure of 3,000 tons, and Huneck (2001) reported that for the year 1997, 1900 tons of Pseudevernia furfuracea and 700 tons of Evernia prunastri were processed at Grasse...Some harvested E. prunastri lichen has been co-gathered with the lichen Pseudevernia furfuracea throughout Europe, but other accounts relate that Striata pulmonacea, Usnea ceratina, Ramalia farinacea, Ramalia fraxinae, Ramalia pollinaria and some Alectoria and Parmelia species are also mixed in from batch to batch (Burfield 2000). Chinese oakmoss, similar in quality to European oakmoss, is reportedly produced from Evernia mesomorpha, and is also commercially available.
Oakmoss preparation. Oakmoss lichen is not fragrant of itself, and it is only the solvent processing operation which generates the fragrant artifacts which give oakmoss its perfumery value. Ironically then, it cannot be classified as a ‘natural product’ according to the many bodies now attempting a definition of this term for the cosmetics trade, as recently reported on the Aromaconnection website.
Preparation of oakmoss concrete is via solvent hydrocarbon extraction (formerly benzene, but nowadays more often cyclohexane, or hexanes, although acetone and other solvents has been used). of the dried, or freshly wetted dried lichen. Resinoids have been obtained historically by hot solvent extraction, and fragrance synthetics have invariably been added in. Formerly, benzene extracted resinoids had found popular use in soap perfumery. Absolutes can be made directly from the concrete, or by refluxing benzene or hexane extracts with alcohol, and hot filtering out the insoluble material - removal of the alcohol give the absolute in 30-60% yield. Diluting the alcohol extract down to 80% and filtering may give a more soluble product with fewer residues, but further ethanol treatment may give a turbid extract, which when mixed with a saturated salt solution and solvent extracted (benzene was formerly used) further amounts of useful product can be obtained. The identity of the alcohol used will determine the odour - methanol gives sweeter smelling esters, and ethanol produces a sharper smelling product.
Oakmoss incolore and molecular distilled grades of oakmoss are also commercially available. Worryingly, Pybus & Sell (1999) state “with some particularly viscous concretes such as those from oakmoss or treemoss, it is more usual to dissolve the concrete in a high boiling solvent, such as bis-2-ethylhexyl phthalate, and then co-distil the product with the solvent.” Hopefully, with current public disquiet over the potential toxicity of phthalates, this practice has been discontinued.
Oakmoss chemistry. As a preface to this section, it may be pertinent to recall Joulain’s (2002) remarks to the effect that although the literature reveals qualitative information about oakmoss composition, there is little quantitative data. The fragrant compounds in oakmoss are generated by the degradative action of the solvents on the naturally occurring depsides in the moss (depsides are phenolics composed by two or three monocyclic units linked by an ester bond and derived from orsellinic acid), generating (volatile) odourous monoaryl substances. The character impact compounds of oakmoss are considered to include methyl b-orcinol carboxylate (methyl atrarate, Evernyl)) which imparts a powdery-mossy note, the monomethyl ether of b-orcellinic acid, methyl & ethyl everniate, and the phenolic compounds orcinol and b-orcinol. Boelens (1997) tabled the various yields from different solvent process (extraction and transesterification of the depsides) for both oakmoss and treemoss, reporting that the odour of oakmoss was preferred to treemoss by an odour panel of expert perfumers. Methyl b-orcinol carboxylate was the chief component of both oakmoss absolute and treemoss absolute products (47% and 57% respectively). The quantities of 3-chloro-2,6-dihydroxy-4-methylbenzoate (Cropwatch comments: this is possibly a misprint in the original article – surely it should have been 3-chloro-2,6-dihydroxy-4-methylbenzaldehyde, or chloroatranol - 10%), 2,6-dihydroxy-4-methlbenzaldehyde (- atranol - 5% and 6% respectively) and methyl 2,4-dihydroxybenzoate (0.5% and 0.7%) were similar. Oakmoss absolute was found to contain had twice as much cembrene (2%) as treemoss absolute. A full account of the work and composition of the benzene extract and benzene/methylanol transesterification products of oakmoss can be found in an earlier paper by Boelens (1993).
Treemoss (Mousse d’arbre) Treemoss derivatives (concretes, absolutes) are mainly prepared from the lichen species Pseudevernia furfuracea (L.) Zopf. with Usnea barbata, Parmelia sulcata and other species often co-gathered in. These tree lichens can both be found living on the barks of firs and pines in Southern and Central Europe including and France and Morocco, & Balkan countries, including former Yugoslavia. Preparation of fragrant treemoss products is carried out in a similar manner to the preparation of oakmoss products, although evidence that isopropanol may be included as a processing solvent is shown by the presence of isopropyl haematommate (which does not exist in lichens) in the analysis of the weakly acidic factions of treemoss absolute (Endo et al. 1999). It should be noted that Treemoss products are generally considered inferior to oakmoss products and command a lower purchasing price.
Tabacchi (1983) acknowledged that pine products are co-gathered with treemoss, and this has caused the sensitising properties of treemoss extracts to be mis-interpreted by toxicologists at that time. More specifically, Joulain (2002) describes work confirming previous observations by Tabacchi that biosynthesized diterpenoid acids from Pinus sylvestris hosts migrate into the oakmoss lichen and assist in their oxidation. The author cites a patented process for producing a treemoss absolute with a low resin acids content but still containing high levels of atranol (0.31%) and chloroatranol (0.15%), which produced no adverse effects at 3% in a suitable solvent in a HRIPT test carried out according to the Marzulli-Maibach protocol with 158 volunteers. Joulain suggested this supported the hypopthesis that 7-oxo-dehydroabietic acid is one of the main sensitizers in treemoss extracts, and that whereas 4-10% of atranorin & chloroatranorin may be present in many treemoss concretes, during the production of absolutes, alcoholysis of the depsides in hot ethanol reduces their content to a level such that they are undetectable by HPLC.
Cedarmoss qualities are derived from Pseudevernia furfuracea Ach. growing on the Atlas cedarwood tree Cedrus atlantica, found mainly in the Atlas Mountains of Morocco. Solvent extraction produces the resinoid (cyclohexane is used as solvent by some manufacturers), followed by distillation to produce an ‘absolute’ although other methods for obtaining the absolute are used. Often sweeter than corresponding oakmoss products, it is used in similar perfumery applications.
IFRA Standards for cedarmoss extracts apply exactly as for treemoss extracts, the logic being that they both originate from Pseudevernia furfuracea (Fr.). Because it may not be collected exclusively on cedar trees, cedarmoss invariably contains pine twigs and wood fragments which affect the properties & odour of the ingredient.
Bernard G., Giménez-Arnau E., Rastogi S.C., Heydorn S., Johansen J.D., Menné T., Goossens A., Andersen K., Lepoittevin J.P. (2003) "Contact allergy to oak moss: search for sensitizing molecules using combined bioassay-guided chemical fractionation, GC-MS, and structure-activity relationship analysis." Archives of dermatological research 295(6), 229-235
Boelens M. (1997): “Production, chemistry and sensory properties of natural isolates” in Flavours and Fragrances ed Kjarl A.D. Swift publ. Royal Society of Chemistry Publications 1997.
Boelens M. (1993) “Formation of volatile componds from oakmoss” Perf & Flav 18(1) 27-30.
Bourgeois G., Suire C., Vivas N. & Vitry C. (1999) "Atraric acid, a marker for epiphytic lichens in the wood used in cooperage: Identification and quantification by GC/MS/(MS)." Analusis 27, 281-283.
Bossi R., Rastogi S.C., Guillaume B., Gimenez-Arnau E., Johansen J.D., Lepoittevin J.-P., Menne T. (2003) "A liquid chromatography-mass spectrometric method for the determination of oak moss allergens atranol and chloroatranol in perfumes." Journal of Separation Science 27(7-8), 537-540. .
Burfield T. (2000) Natural aromatic materials – origins & odours. Publ. AIA, Tampa 2000.
Endo H., Andatsu M. & Ishihara M. “Chemical components of treemoss absolute”, (1999).” 43rd TEAC Oita Japan.
Filho L.X., Pereira E.C., Vicente C., & Legaz M.-E. (2004) "Synthesis of methyl-3-orsellinate by organic synthesis or by altered biosynthetic pathways using lichen immobilisates." ARKIVOC 2004 (vi) 5-11.
Gonçalo S. (1988) “Contact sensitivity to oakmoss” Contact Dermatitis 19, 355-7.
Huneck S (2001).. Progr. Chem. Org. Nat. Prod. 81, 1.
Joulain D. & Guillamon N. (2002) "Pseudevernia furfuracea ("treemoss") resinoid in fragrance compounding: Analytical issues." Presented at 46th TEAC Symposium Tokushima, Japan (2002).
Joulain D. (2002) “Stable Isotopes for determining the origin of flavour & fragrance components: recent findings.” In: Advances in flavours & fragrances from the sensation to the synthesis.ed. Karl A.D. Swift publ. Royal Soc. Chem 2002. Section 5 is: “The case of a natural raw material for fragrances: lichen resinoids.”
Joulain D., Guillamon N., Casazza A. & Tabacchi R. (2005) “New insight in the knowledge of the qualitative and quantitative composition of oakmoss resinoids.” 36th International Symposium on Essential Oils, 4-7 September, Budapest, Hungary.
Kumar S.K.. & Muller K. (1999) “Lichen metabolites. 1. Inhibitory action against leukotriene B4 biosynthesis by a non-redox mechanism.” Journal of Natural Products 62(6), 817-820.
Moxham T.H. (1986) “The commercial exploitation of lichens for the perfume industry.” In Progress in Essential Oil Research Walter de Gruyter Berlin – NY (1986).
Pybus D. & Sell C. (1999) The chemistry of fragrances. Pub Royal Soc. Chemistry (GB) p37:
Rastogi S.C., Bossi R., Johansen J.D., Menné T., Bernard G., Giménez-Arnau E., Lepoittevin J.P.. (2004) "Content of oak moss allergens atranol and chloroatranol in perfumes and similar products." Contact Dermatitis 50(6):367-70
Schnuch A., Uter W., Geier J, Lessmann H. & Frosch PJ. (2007) "Sensitization to 26 fragrances to be labelled according to current European regulation. Results of the IVDK and review of the literature." Contact Dermatitis 57(1), 1-10.
Tabacchi J. (1983) “Contributions to the knowledge of chemical composition of tree moss Pseudoervinia furfuranaceae L. Zopf.” Proceedings of 9th International Congress of Essential Oils Singapore 65-68. (1983).
August 26, 2008
Incense may cause cancer
Reuters (and a lot of others) report on a study that suggests that "regularly inhaling the smoke could put people at risk of cancers of the respiratory tract." The findings are published in the medical journal Cancer for October 1, 2008 (not online yet).
The study examined incense use by 61,320 Singapore Chinese men and women for 12 years. Subjects reported on their incense use and the researchers followed their health.
The researchers found that incense use was associated with a statistically significant higher risk of cancers of the upper respiratory tract, with the exception of nasopharyngeal cancer. However, they observed no overall effect on lung cancer risk.
Without looking at the original study, it's hard to tell what the relationship might be with natural ingredients or species of the incense ingredients. It seems likely that it is the smoke particles that are the carcinogenic ingredient. If that is the case, the type of incense and the source may be irrelevant. However, the researchers note that further studies are needed to determine if these are factors.
A slightly different article was found in HealthDay.
August 20, 2008
Notes and News
- The online Perfumer&Flavorist features a visit to Shady Lane Farms, a mint farm in Indiana, complete with a photo album that includes harvesting and distillation.
- HerbalGram #79 (August-October 2008) features Valerian as its Herbal Profile. It also includes a short article on the NPA Natural Seal program, a Research Review on the efficacy of South African Geranium (Pelargoinium sidoides) in the treatment of acute bronchitis, and a feature article on the African fixed oil Marula (Sclerocarya birrea) that may have some value for personal care products.
- According to Natural Products Insider, an Oregano Manufacturer has paid $2.5 million to settle an FTC case for claims that its oregano oil and capsules could kill germs. Airborne settled a similar case that it did not have adequate evidence to support its advertising claims.
- Botany Photo of the Day featured Sitka Valerian on August 8, with links to pollinator information.
- 1000fragrances blogs about the invention of "a device for obtaining perfume from living plants"--160 years ago.
August 11, 2008
EFFA’s Citral, Farnesol & Phenylacetaldehyde submission is thrown out by the SCCP
(Being an excerpt from forthcoming Cropwatch Newsletter August 2008)
by Tony Burfield August 2008.
Curiously ignored by the cosmetics trade press, whose hacks probably failed to understand its significance, the Scientific Committee on Cosmetic Products (SCCP) Opinion SCCP/1153/08 on Dermal Sensitisation: Quantitative Risk Assessment (QRA) for Citral, Farnesol and Phenylacetaldehyde (adopted 24th June 2008) threw out the ‘industry-proposed’ QRA approach for setting safe levels of exposure to citral, farnesol and phenylacetaldehyde in cosmetic products. The Opinion is extensively argued & fairly damning - the SCCP noted that the QRA approach is based on data from experimental sensitisation tests on humans e.g. the Human Repeated Insult Patch Tests (HRIPT) and that model suffers a lack of detailed method description, application experience, is not (yet) validated, and has no strategy to make it so. Epidemiological & experimental data are not integrated into the QRA model; & whereas the model allows for various product categories of exposure, the risks from aggregated exposure (including occupational exposures) are not considered. The SCCP further remark that there is no scientific consensus on the safety factors used. Perhaps most tellingly, the committee consider that safe levels of exposure to existing substances known to cause allergic contact dermatitis in the consumer should be based on clinical data and/or elicitation low-effect levels (Cropwatch comments: as has proven successful for nickel & chromium allergic contact dermatitis). In this light, the required data for citral, farnesol & phenylacetaldehyde was not forthcoming, in spite of a specific request made by Brussels for EFFA to provide it.(all that was provided were a series of model-generated numbers, the relevance of which, in terms of consumer safety, being unknown).
Cropwatch had previously put forward an objection to SCCP ‘expert’ committee over the EFFA submission (of IFRA QRA-based data) on citral, farnesol & phenylacetaldehyde, a copy of which can be seen at http://www.cropwatch.org/objectcitral.pdf. Cropwatch had maintained that this particular submission passed on by EFFA was uniquely important, because it represented first use of the QRA methodology in submissions to the SCCP ‘expert’ committee, to further restrict newly alleged allergens (a process we described as ‘sneaking allergens in by the back-door’). Since the existing classification of allergens under 2003/15/EC has proven so scientifically controversial, it seemed both inappropriate and extremely unwise to legislate to include further allergens in the Cosmetics Directive until the underlying science is better sorted out.
To recap, a considerable head of pressure is building up over the apparent misclassification of a number of fragrance chemicals as allergens under Council Directive 2003/15/EC (the ‘26 allergens’ debacle) which is becoming impossible to ignore. Amongst the highlights of relevance here, you will remember that Storrs (2007) pointed out that the basis for inclusion of fragrance ingredients as allergens has never been defined by the SCCP committee, that Schnuch et al. (2004) have presented evidence showing that an number of fragrance chemicals listed in the ‘26 allergens’ debacle (including citral & farnesol), are rarely found as allergens, and that Sanchez-Politta et al. (2007) had indicated that there was little independent peer-reviewed evidence to support the case showing phenylacetaldehyde as a sensitiser. It is not immediately apparent therefore why EFFA chose to make this QRA-based submission in such an incomplete form, as they must have expected rejection. .
Perhaps at this point we should pause briefly, to explain some procedural theory. The QRA is basically an exposure-based methodology for dermal sensitisation risk assessment, a key component of which is consideration of the dose (of sensitiser) per unit area to determine sensitiser potency. IFRA has expressed its intention to employ this particular methodology "as the core strategy for primary prevention of dermal sensitisation to these materials in consumer products.” Allergic contact dermatitis itself is a skin disease which is classically considered to arise from a series of immunological events, the first being an induction process from a low-molecular weight chemical (for example, a component of an essential oil). Continued exposure to this chemical at a sufficient concentration gives rise to an elicitation process which results in the physical manifestation of the disease. Risk assessment models to predict the potential skin sensitisation potential of fragrance ingredients incorporate three factors: predicted no-effect levels of sensitisation under experimental conditions, an appropriately deemed safety factor, and an exposure assessment. No-effect levels can be derived from predictive tests to determine the sensitisation potency of fragrance ingredients using animal based methodology (as in the Murine Local Lymph Node Assay or LLNA), or by using humans volunteers via the Human Repeated Insult Patch Test (HRIPT). In the HRIPT, fragrance ingredients are tested at ten times the use level on healthy human volunteers – if sensitization occurs, the maximum permitted level is taken as a tenth of the no effect level - but the HRIPT test is now considered an unethical procedure. Results obtained in the LLNA test can be mathematically treated to give an EC3 value (the concentration causing a threefold increase in the lymph node stimulation index) which is obtained by linear interpolation of the LLNA response data; these values being used to give an estimate of sensitiser potency, or to rank contact allergens.
Overall Cropwatch has major concerns over the interpretation of data obtained from these procedures - amongst them are worries that these predictive tests do not sufficiently distinguish between (weak) sensitisers and irritants; that outcomes for single ingredients are highly dependent on test substance purity (which is causing on-going controversy e.g. in the cases of linalool & coumarin), and that, anyway, different animal-based tests (such as rat popliteal lymph node assay or PLNA) yield conflicting results to the LLNA. For example, the LLNA results categorise citral as a low to medium potency sensitiser, whereas Friedrich et al. (2007) found that citral was an irritant & not an immuno- sensitising substance at all, in primary positive PLNA responses.
Regarding the occurrence of the individual fragrance ingredients in question, we explained in our submitted objection detailed above, citral is a mixture of two acyclic monoterpenoids, neral & geranial, which can be regarded as branched chain aliphatic unsaturated aldehydes (cis- and trans-3,7-dimethyl-2,6-octadien-1-al). Citral occurs widely in varying component isomer ratios in many natural products including citrus oils, & concentrated and terpeneless citrus oils such as lemon oil & orange oils, in lemongrass oils, Litsea cubeba oil, black pepper oil, verbena oil, melissa oil, ginger oil, etc. etc. In layman’s terms, most people are regularly exposed to citral in their daily lives e.g. hand exposure occurs when peeling & cutting citrus fruits, and citral is regularly imbibed in the diet as a natural or synthetic flavouring component of some spices and in fruit-based or fruit-flavoured soft drinks.
Farnesol a common sesquiterpene alcohol component of many essential oils, the isomers of which may be typically be found to 4.5% in neroli oil, and to 1% in rose oil. E,E-farnesol also occurs in Santalum spicatum (Australian sandalwood) oils and extracts to 5% (subject to confirmation, IFRA quote to 8%), which distinguishes it from the lower concentrations found in the oil of Santalum album (E.I. Sandalwood). Farnesol is also an impurity in many commercial grades of bisabolol; Cropwatch has recently described [http://www.cropwatch.org/newslet8.pdf] the demise of the Candeia Plant (Eremanthus erythropappus) which was harvested to the point of extinction in the Atlantic Brazilian rainforest to furnish demand from the German pharmaceutical trade for its natural (-)-a-bisabolol content.
Phenylacetaldehyde has a piercing green odor, which on dilution is reminiscent of hyacinths, and is a minor component of many essential oils and fruits – for example it occurs at up to 5% in the headspace of the sweet-pea blossom, Lathyrus odoratus.
To sum up, it remains to be seen whether the SCCP committee will be able to stick to the principles enshrined in their Opinion SCCP/1153/08, in the face of inevitable pressure from industry, and are able to insist that clinical evidence be provided which shows that allergic contact dermatitis is unequivocally linked to exposure effects from specific fragrance chemicals. If they are able to maintain this, and the required forensic examinations of the available clinical & experimental evidence are independently carried out, the list of allergens fulfilling the required allergenic listing criteria could be very short, and the committee will need to reverse their own previous Opinion on allergens & make changes to Directive 2003/15/EC. Meanwhile IFRA plunges even deeper into its predictive QRA-based sensitiser policy, with the announcement of the 43rd IFRA Amendment (a summary of which will be put out by Cropwatch shortly). Remember, in spite of the pretence of a state of voluntary regulation, IFRA & EFFA members are required to fulfill the requirements of the IFRA CoP to the letter, right or wrong. Overall therefore, the casual observer could be forgiven for thinking that the gulf between toxicological theory/conjecture about sensitisation issues, and the link to robust clinical evidence, is becoming an ever-wider chasm, and we are merely observers in a power-struggle between toxicologists & regulators. Cropwatch pessimistically believes the outcome is inevitable - the regulators salaries depend on the continual passing of new legislation (whether it is appropriate or not) and the data-providing toxicology machine is now the most powerful force in the aroma/cosmetics world. One way or another therefore, aroma ingredients will continue to be restricted & prohibited unnecessarily. The status quo is maintained by the attitude of the fragrance customers, who seem to worry little about whether legislation is either scientifically sound or fair, they just want to know that the fragrance providers are following the current rule-book.
Friedrich K., Delgado I.F., Santos L.M.F., Paumgartten (2007) "Assessment of sensitisation potential of monoterpenes using the rat popliteal lymph node assay." Food & Chemical Toxicology 45 (2007), 1576-1322.
Sanchez-Politta S, Campanelli A, Pashe-Koo F, Saurat JH, Piletta P. (2007) "Allergic contact dermatitis to phenylacetaldehyde: a forgotten allergen?" Contact Dermatitis 56(3),171-2.
Schnuch A., Uter W., Geier J., Lessmann H. & Frosch PJ. (2004) "Contact allergy to farnesol in 2021 consecutively patch tested patients. Results of the IVDK." Contact Dermatitis. 50(3), 117-21. Schnuch A. (2005) Öko-Test, No. 7 (July) 2004, 55
Schnuch A., Uter W., Geier J., Lessmann H., Frosch P.J. (2007) “Sensitization to 26 fragrances to be labelled according to current European regulation. Results of the IVDK and review of the literature.” Contact Dermatitis. 57(1), 1-10.
Storrs F.J. (2007) “Allergen of the year: fragrance.” Dermatitis 18(1), 3-7.
UN Numbers for Essential Oils Updated
A friend asked me how to determine what these numbers are for essential oils, since the number is requested on the shipping forms from most shippers. After spending an afternoon researching the question, and realizing that it is rather obscure, I decided to share what I learned with the world.
The prefix UN is followed by 4 numbers ranging from 0000 to 3500, There are also NA numbers usually starting with 8 or 9 that identify items that haven't been assigned an actual UN number. You may see the 4 digit number on a diamond shaped sign on a tank truck on the highway. Sometimes they are referred to as UN/NA numbers.
The problem with identifying the numbers for essential oils is there isn't a one to one correspondence between a UN number and an essential oil. A number of essential oils may fit into one UN Number. The UN Number is associated with the MSDS sheet for an oil, but there is no requirement to put that number on the MSDS sheet.
In researching this, I determined that there are at least six different numbers that can be assigned to a an essential oil: CAS. IUPAC, EINECS, FEMA, UN, and FDA. There is an effort to develop a Globally Harmonized System (GHS) for all chemicals. But that's another story.
I discovered an Excel spreadsheet on the website of the (US) Office of Hazardous Materials Safety. I downloaded it and analyzed it, but it didn't seem too useful for our purposes, since I could only find about 50 items out of over 3000 that might include an essential oil or an essential oil component. These are the classifications that essential oils fall into. But which ones?
I finally discovered a Word document [Update 2010: Go to html Version of 2009 COP information instead] prepared by EFFA (the European Flavor and Fragrance Association) as an introduction to its 2008 Code of Practice. When I went to the EFFA Home page, lo and behold--a link to this introduction and its 3 Annexes: Attachment 1 for chemicals, Attachment 2 for complex natural substances, and Attachment 3 for potential hazards from complex natural substances. The Attachments are Excel spreadsheets that can be downloaded. [Update 2010 – All six tables for the CoP are now in one Excel file called Attachments.]
Right now I leave it to the reader to decipher what all the abbreviations mean. If you are shipping essential oils, you can use the table in Attachment 2 to look up the UN Number, the Hazard Class, and the Packaging Group. Then you'll have to follow the instructions of your shipper. Most shippers have training classes available for a nominal fee.
If you want to figure it out for yourself, the packaging rules for the US are included in the Code of Federal Regulations Title 49 Part 173. The HMT spreadsheet from the Office of Hazardous Materials Safety mentioned above tells you which Sections apply. For example, from the EFFA table you can determine that frankincense (called olibanum there) is UN1169, Class 3, Packaging Group III. If you go to the HMT table you will see that UN1169 is Extracts, Aromatic, liquid and for non-bulk shipping you need to go to section 203. The link to that is here. When you get there you can look up other sections by going to the top level and then finding the other section in the contents.
Note that all these regulations (in the US at least) only apply when you are shipping regulated hazardous materials in containers over 1 ounce. There are packaging rules here that you will have to meet for smaller quantities. There may be some other exceptions but I haven't figured them out.
The regulations are complex and figuring them out is difficult. I hope this information helps you find your way through the jungle. However, I take no responsibility if you don't get it right.
August 02, 2008
Saturday Night Lavender Blogging
I found this while Googling bees and lavender to respond to a comment recently added to an old post from dave, who inquired about why bees become docile while on his lavender. He notes that some have died.
Has anyone else observed this phenomenon?