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September 25, 2009

Cropwatch Newsletter 16: Disproportionate Reactions to Health & Safety Issues

Cropwatch Newsletter 16 has been received by email subscribers. Contents include the following:

  • DEFRA vs Georgina Downs
  • IFRA & Transgressors
  • Robertet Reveals its Evidence on Melissa oil
  • Safrole & Human Carcinogenicity?
  • EU Commission’s Proposals to Limit FC’s in Cosmetic Products
  • Cropwatch’s Letter Objecting to EU Proposals on FC’s Limits
  • Save Our Herbs Campaign: Press Release/Website.

It’s also available online in pdf format.

Note that you can sign up on the Cropwatch website to receive their newsletters via email, usually a few days in advance of their online posting. Several of the articles in the Newsletter were previously posted on this blog, but there is a lot of additional information available in the Cropwatch Newsletters.

Posted by Rob on September 25, 2009 in Essential Oils/Plant Extractions, Regulatory Issues, Safety/Toxicity | Permalink | Comments (1) | TrackBack

September 20, 2009

Does Jojoba Oil Contain Myristic Acid?

Jojoba Oil or Wax from Simmondsia chinensis is claimed on several thousand web sites to contain Myristic Acid, but I have found no evidence that it is present in more than a trace amount. I began looking into this while researching Jojoba oil for Samara Botane’s new website (still a work in progress). When I started looking into it (via Wikipedia—not necessarily a good source) and a variety of other sources, I found that things are somewhat confusing. This article reveals the sordid truth.

Note for the chemistry impaired: The naming conventions for fatty acids are somewhat confusing, with many different names often used for the same acid. To reduce the confusion factor, it has become a convention to refer to a fatty acid by a C followed by a two part number with a colon in between denoting the number of carbon atoms and the number of double or triple bonds, e.g. C14:0 is myristic acid which has 14 carbon atoms and no double or triple bonds. Monounsaturated acids have one double bond e.g. C18:1 oleic acid, and polyunsaturated acids have multiple double bonds e.g. C18:2 is linoleic acid and C18:3 is linolenic acid.
An Ester consists of an acid and an alcohol connected into a single compound, but apparently when identified by MSGC, the two components show up as separate peaks.

Jojoba Oil

Jojoba Oil is a liquid wax produced from the seed of Simmondsia chinensis, a shrub native to the Southwestern US and Northern Mexico. According to Wikipedia, it is a mixture of long chain wax esters, 36 to 46 carbon atoms. It is liquid at room temperature, which is why it is called a liquid wax, or an oil—even though it is not an oil. The long chain esters consist of a fatty acid that is attached to an alcohol by an ester bond. What this means, apparently, is that jojoba oil can appear to be constituted of fatty acids and fatty acids as well as the fatty ester that it is actually made up of. Note that this particular chemical makeup appears to be unique to jojoba, although it has some characteristics similar to human sebum and whale oil, which is one of the reasons that it is valued in the cosmetics industry.

Although as we shall see, the claims vary, the principle fatty acids in Jojoba wax according to Wikipedia are Eicosenoic C20:0 (66-71%), Docosanoic C22:0(14-20%) and Oleic C18:1 (10-13%). Price (1999) counts it up differently, with Saturated fatty acids palmitic C16:0 (11%), stearic C18:0 (71%), arachidic C20:0 (14%); monounsaturates oleic C18:1 (6.7%) and curiously not mentioning myristic acid at all in his Principal Constituents table on p. 85.

Myristic Acid

Myristic Acid is also called tetradecanoic acid or C14:0. It is classified as a medium chain fatty acid because it has 14 carbon atoms and it is a Saturated fatty acid because it has no double or triple bonds. It is named after the nutmeg (Myristica fragrans) where it was originally isolated,  It is also found in palm oil, coconut oil, butter fat, and spermacetin, the crystallized fraction of oil from the sperm whale. Note that Wikipedia, the source for the above information, doesn’t mention jojoba.

The Claims

Since Price didn’t mention myristic acid in his table of Principal Constituents, I was curious as to why he stated on p. 86 that jojoba “contains myristic acid which is an antiinflammatory (sic) agent . . .”. To find out I did a Google search on “Jojoba”, “Myristic Acid” and to my amazement got 57,100 hits. Admittedly, just because these two terms occur in the same webpage doesn’t mean they are actually connected, but browsing through the first 20-40 hits revealed they they all were connected, with statements like “It contains myristic acid which also has an anti-inflammatory action”, “Jojoba also contains myristic acid, which has anti-inflammatory properties”, “Organic jojoba contains a natural anti-inflammatory called myristic acid”, all of which were clearly referring to jojoba. I added the term “anti-inflammatory” to my search and now got 2,190 hits.

Of course most of the top level hits were from commercial sites trying to sell jojoba oil and apparently not going beyond reading p. 86 in Price. About 50 hits down, I started getting into some books that I thought might reveal the truth. I’m not going to provide a complete list here, but suffice it to say that several supposedly authoritative books are getting crossed off my list of sources. I eventually jumped ahead to 300 or more, and here I started getting a higher number of hits that listed ingredients or had several oils on one page and were not claiming myristic acid in jojoba—but there were still a number of the same old claims. Finally, after 626 hits, Google stopped delivering new stuff, so I gave up on that search phrase, and started to try to find something more authoritative. I added “MSGC”  or “Composition” to my search.

The Facts

The first thing I found a table that showed the constituents of jojoba by chain length, starting with C16 and going up to C24 (Kleiman 1990).  No C14 here.

Next, I found the original study from 1975 (National Academy of Sciences, 1975). Table 2 shows the Alcohol/Acid Structures of Jojoba Oil Determined by Gas Chromatography, Mass Spectrometry, and Ozonolysis. This should be an authorative source! And it mentions C14:0 as well as C12:0 and C16:0. All three were found in “trace” amounts. Effectively, no C14:0 here.

OK, what about Wisniak’s book about Jojoba? Table 1-26 is the same table as the 1975 NAS study and Spencer et al, but “trace” is defined as 0.01-0.05%. Not much C14:0 here either. Table 1-27 looks at the Jojoba Oil Wax Ester Composition and breaks down the long chain esters by their Alcohol/acid combination. No C14 in the table, as would be expected. Table 1-28 looks at the Composition of Fatty Acid Methyl Esters and Fatty Alcohol Acetates Derived from Jojoba Wax. Again C12, C14, and C15 acids are only in trace quantities.

Here’s another without C14:

Triglyceride compounds isolated from jojoba seed oil by column chromatography were composed predominantly of C18′ C20′ C22′ and C24 n−9 fatty acids with minor amounts of saturated C16. (van Boven et al Abstract)

And another:

The results wax indicated that the main constituents in jojoba wax were various kinds of wax esters, namely eicosenyl octadecenoate (C20:1-C18:1)(1), eicosenyl directly, eicosenoate (C20:1-C20:1)(II), docosenyl eicosenoate (C22:1-C20:1)(III), eicosenyl docosenoate (C20:1-C22:1)(IV) and tetracosenyl eiosenoate (C24:1-C20:1)(V). . . . The concentrations of the wax esters I, II and III, in jojoba wax were 5.5, 21.4 and 37.8%, respectively. (Tada et al)

Finally, I did find one curious document on the Internet (Simon, 2006)that possibly needs to be given some credence and which includes myristic acid among the constituents of Jojoba Oil. It has no documented sources so it’s not clear where the information came from. It is a “Technical Memorandum” written for the Michigan Department of Environmental Quality (MDEQ) listing secondary Constituents of Interest (COI) for substances used or produced at the Dow Chemical Plant in Midland, Michigan. This list was to be used to identify pollutants in the nearby rivers that might have originated in the plant. The purpose of this document was to resolve discrepancies in their data base, and one of the entries is (in a table entitled CASE NARRATIVE – Multi-Compound Listings):

456 Jojoba Ester – High Internal Phase (Myristic Acid, Palmetic (sic) Acid, Oleic Acid, Eicosenic Acid, Erucic Acid, Nervonic Acid, Eiconsenol, Docosenol, Tetracosenol) DOW RESOLVED. Multi-compound listing individual components are [544-63-8] myristic acid, (remainder of items omitted here – rs)

The number in [] brackets is the CAS number of myristic acid.


Based on the studies referenced above, there are no appreciable amounts of myristic acid in jojoba oil. This doesn’t necessarily mean that there isn’t genetic or geographic variation (Busson-Breysse et al), but I haven’t found any evidence that that has occurred. If anyone is to make a valid claim that there is C14:0 in jojoba, they need to present their proof. In the meantime, Internet vendors should stop making claims that Jojoba Oil contains Myristic Acid.


http://en.wikipedia.org/wiki/Jojoba_oil Accessed 9/19/2009

http://en.wikipedia.org/wiki/Myristic_acid Accessed 9/19/2009

Busson-Breysse J., M.Farines, J.Soulier, “Jojoba wax: Its esters and some of its minor components” in Journal of the American Oil Chemists’ Society, 71 (1994) Abstract accessed 9/20/2009.

Clark, Sue Essential chemistry for safe aromatherapy, Elsevier, 2002 Accessed in Google Books 9/19/2009

Kleiman, R “Chemistry of New industrial Oilseed Crops”  http://www.hort.purdue.edu/newcrop/proceedings1990/v1-196.html#Table%205 accessed 9/19/2009

National Academy of Sciences, 1975. Jojoba: Feasibility for Cultivation on Indian Reservations in the Sonoran Desert Region. Accessed on Google Books.

Price, Len, Carrier Oils for Aromatherapy & Massage, Third Edition. Stratford-upon-Avon: Riverhead Press, 1999.

Simon, PB and Simon, PM “Technical Memorandum to Mr. Allan Taylor, MDEQ Waste and Hazardous Materials Division” , Dec 1, 2006. PDF Accessed 9/20/2009.

Spencer, G.F, RD Plattner and T. Miwa, “Jojoba Oil Analysis by High Pressure Liquid Chromatography and Gas Chromatography/Mass Spectrometry” Journal of the American Oil Chemists Society, 1977 Accessed 9/20/2009.

Tada, Atsuko, Zhe-Long Jin, Naoki Sugimoto, Kyoko Sato, Takeshi Yamazaki, Kenichi Tanamoto “Analysis of the constituents in jojoba wax used as a food additive by LC/MS/MS,” Shokuhin Eiseigaku Zasshi. 2005 Oct ;46 (5):198-204 16305174 (P,S,G,E,B) Abstract accessed 9/20/2009

Van Boven M., RA Holser, M , Cokelaere, E. Decuypere, C Goveaerts and J. Lemy, “Characterization of triglycerides isolated from jojoba oil,” Journal of the American Oil Chemists’ Society, 77 (2000) Abstract accessed 9/20/2009.

Wisniak, J., The Chemistry and technology of jojoba oil. American Oil Chemists Society, Accessed on Google Books

Posted by Rob on September 20, 2009 in Essential Oils/Plant Extractions, Massage, Oil Crops | Permalink | Comments (3) | TrackBack

September 18, 2009

Safrole: Human Carcinogenicity Risk Over-Stated?

Copyright © Tony Burfield September 2009.

Updated to include additional references 9/19/2009


It almost borders on the heretical, perhaps, to suggest that the risk of human carcinogenicity from exposure to dietary safrole has been over-estimated over the years by some toxicologists, and that the existing national & international restrictions on safrole-containing ingredients & end-products can be seen as over-precautious. Weighing the evidence, a convincing case can be made that the human carcinogenic potential of safrole, if not quite negligible at low doses, is considerably less than that of ethanol (Duke 2002). As it is, the existing evidence for the carcinogenicity and genotoxicity of safrole mainly rests on a battery of experiments performed 30-40 years ago, on laboratory rodents dosed with high levels of safrole, where electrophilic metabolites generated by P450 enzymes and sulphurotransferases are identifiable as being responsible for the genotoxicity (see Cropwatch’s extensive Safrole Bibliography at http://www.cropwatch.org/Safrole Bibliography.pdf). Different expert judgments have been made about the risk to humans from alkylbenzenes such as safrole, methyleugenol & estragole, and indeed on the relative importance for human cancer of low-dose exposures to synthetic chemicals generally (Gold et al. 1992). More insight into bioactivation of these (alkylbenzene) compounds in humans has been said to be required to interpret animal data to the human situation (Jeurissen 2007).

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Safrole (4-allyl-1,2-methylenedioxybenzene; CAS No. 94-59-7) is known to occurs in the following natural products:

  • Chinese Angelica (Angelica sinensis L.)
  • Betel oil (Piper betle L.)
  • Brown & yellow camphor oil (fractions of Cinnamomum camphora L.) Yellow oil to 20%; brown oil to 80%.
  • Cangerana oil (Cabralea cangerana Saldanha)
  • Cinnamon leaf oil & bark oils (Cinnamomum zeylanicum Blume) both to 2%
  • Kuromoji oil (Lindera spp.) to 12%
  • Mace oil (Myristica fragrans Houtt.) to 2%
  • Mango ginger oil (Curcuma amada Roxb.) to 9.5%
  • Nutmeg oils [E.I. & W.I.], butter & oleoresins (Myristica fragrans Houtt.) E.I, to 2%; W.I. to 0.3%’
  • Pepper oil, black (Piper nigrum L.)
  • Piper auritum HBK oil to 90%
  • Sassafras oils, bark of roots, infusions of roots (Sassafras albidum (Nutt.) Nees to 95%.
  • Sassafras oil Brazilian: Ocotea pretosia (Nees) Mez, to 92%
  • Star Anise oil (Illicium verum Hook f.)
  • Ylang-ylang oils, absolutes (Cananga odorata (DC) Hook. f et Thoms ­subsp. genuine)

…as well as in several other Cinnamomum essential oils (C. burmanni; C. porrectum; C. rigidissum etc.). It also in occurs in witch-hazel (Hamamelis viginiana L.), hoja santa leaves (Piper auritum HBK) and in other natural herbal & spice products & preparations.

Safrole is currently classified as a carcinogen category 2 and mutagen category 3 in the IFRA-IOFI labeling manual 2009. Since out of the three alleged human carcinogens: safrole, estragole and methyl eugenol, safrole is arguably the weakest (see below), these classifications seem somewhat arbitrary.


Hazard symbol

Risk phrases

Carcinogen category

Mutagen category











Methyl eugenol





Classification of some Carcinogens & Mutagens according to the IFRA-IOFI Labelling Manual 2009

[*Thanks to Penny Williams of Formpak Ltd. for drawing our attention to this labeling issue; further implications over R68 status for estragole & methyl eugenol affecting common essential oils such as Aniseed, Bay, Basil, Fennel and Pine Oil Yarmor, are discussed at http://www.formpak-software.com/active/2009/09/estragol-methyl-eugenol-r68/].

Previously the IARC had surmised that safrole was “Reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity in experimental animals” (IARC 1976); but that “No adequate human studies of the relationship between exposure to safrole and human cancer have been reported” (- IARC 1976). The weak potency of safrole as a carcinogen is illustrated by the fact that level of safrole in the diet of rats necessary to elicit liver tumors ranges from 0.5% to 5.0% (Patri et al. 2002). The TD50 for safrole in rats was found to be 440mg/Kg/d (Gold et al.) compared with 51mg/Kg/d for mice. This compares with a TD50 value for methyl eugenol of 20mg/Kg/d for rats and 19mg/Kg/d for mice. However the TD50 for the proximate carcinogen 1’-hydroxysafrole was found to be 18mg/Kg/d for rats compared with 71 mg/Kg/d for mice.

The hazardous dose of sassafras oil for humans (which typically contains 80% safrole) has been put at 0.66 mg/Kg, based on experimental animal data, and a safety factor of x100; this is claimed to be way- exceeded by imbibing a standard portion of sassafras tea which has been estimated to give a dose of 3mg/Kg for a 60Kg man (Bisset 1994; Segelaman 1976). By comparison Levy (Levy undated) gives a figure of 20 ppm safrole content of root beer before the sassafras FDA prohibition, approximating to a 5mg dose for an 8oz serving. Safrole-free extracts of sassafras have been approved by the FDA for food flavouring use, but apart from being organoleptically inferior, it is also of note that safrole-free extracts of sassafras have produced malignant mesenchymal tumors in laboratory rats (Benedetti et al. 1977).

Safrole & sassafras oil were banned as food & flavouring additives by the FDA on 3rd Dec 1960 (FDA Ban 21 CFR 189.180; revised April 1 2008), the ban now includes isosafrole & dihydrosafrole (the latter not being known in nature), & sassafras root bark, but in practice both sassafras oil and bark are still widely available in the US, from health food stores and internet suppliers. Safrole appears in Annex II/360 of the EU Cosmetics Directive EU 76/768, and its concentration is limited to 100ppm in finished cosmetic products (50 ppm for oral/dental use; zero for children’s toothpaste). IFRA prohibits the addition of safrole to fragrances as such, and limits the safrole content of perfumes formulated with safrole-containing essential oils (basil, nutmeg, sassafras, cinnamon leaf etc.) to 0.01% (100ppm) for both skin contact & non-skin contact fragrances. These restrictions have caused a significant problem with certain fragrance styles entering the market place – for example in the deployment of cinnamon & nutmeg ingredients in masculine fougères and spicy masculine notes.

The restriction of safrole to low levels in foodstuffs was originally considered to be a threat to the economic welfare of the nutmeg trade, and so exceptions were made (note that curiously, no such exceptions are ever made for natural ingredients in the cosmetics area, presumably because academic ‘expert’ committees in this field are unable to accurately predict the socio-economic effects of their policies). European Council’s Directive on food flavourings 88/388/EEC, amended by 91/71/EEC and implemented into UK national law in the Flavourings in Food Regulations 1992, limits safrole in foodstuffs to 1ppm, except for foodstuffs containing nutmeg (15ppm) or alcoholic drinks >25% volume alcohol (5ppm) and other alcoholic drinks (2ppm). It is of interest to note that Choong & Lin (2001) analysed 25 soft drinks, including Coca-cola and Pepsi, from supermarkets & convenience stores in Tainan and Pingtung, for safrole and isosafrole contents in 1998, finding 20 out of 25 soft drink samples contained safrole and/or cis-isosafrole and the contents of safrole were up to 3-5 times the use limit of 1μg/mL according to the food additive regulations.

Isosafrole (CAS No. 120-8-1), which occurs as (E)- & (Z)- geometric isomers, is a weak, non-genotoxic rodent hepatocarcinogen, classified as a carcinogen category 3 (IARC 1987) which has been alleged to occur in minor amounts in certain essential oils (such as Chinese angelica oil from Angelica polymorpha Max.), ylang-ylang & nutmeg oil & oleoresin, but Lawrence could not confirm its presence in nutmeg oils (Lawrence 1990), and MAFF have disputed its presence in ylang ylang & sassafras products (MAFF 1996a). However MAFF (1994) found 0.1% to 3.4% isosafrole (av. 0.3%) in 10 analysed samples of nutmeg oil and 0.1 to 2.7% (av. 0.9%) in 3 analysed nutmeg oleoresin samples (origins not disclosed). Since isosafrole usually co-occurs with safrole in certain natural products, at concentrations typically an order of magnitude lower than the safrole concentration (MAFF 1996), it was proposed by MAFF that isosafrole is an artifact formed during the processing of safrole-containing raw materials.

Safrole Metabolism

Intraperitoneal dosing of rats and guinea pigs with safrole produces the following urinary metabolites; 1,2-dihydroxyl-4-allylbenzene, 1'-hydroxysafrole, 2-methylenedioxy-4-(2,3-dihyroxypropyl)benzene, 1,2-dihydroxy-4-(2,3-dihydroxypropyl)benzene, 2-hydroxy-3-(3,4-methylenedioxyphenyl) propanoic acid, and 3,4-methylenedioxybenzoylglycine (Stillwell et al. 1974). Two pathways have been proposed whereby hepatotoxic substances are produced from safrole (Dietz & Bolton 2007). The first proceeds via the P450 catalyzed hydroxylation of safrole to 1'-hydroxysafrole, and its subsequent conjugation with sulfate to produce a reactive sulfate ester, which creates creates a highly reactive carbocation via a SN1 displacement, which alkylates DNA. The second pathway involves the formation of hydroxychavicol via the P450 catalyzed hydroxylation of the methylenedioxy ring of safrole, which is subsequently oxidized to an o-quinone, which non-enzymically isomerizes p-quinone methide. Dietz & Bolton (2007) consider that these experiments by Bolton et al. (1994), Miller et al. (1985), Boberg et al. (1983), Daimon et al. (1997-1998) & Jeng et al. (2004) and the in vitro & in vivo experiments of Luo & Guenthner (1997), Gupta et al. (1993), Randerath et al. (1993), Daimon et al. (1998) & Daimon et al. (1997) prove the genotoxic effects of safrole and justify the regulatory action of the FDA & other authorities. Cropwatch takes issue with this conclusion; the mere existence of pathways in rodents fed high levels of dietary safrole which give rise to certain hepatotoxic substances does not, of itself, prove the potential for human carcinogenicity under normal living circumstances.

Although small amounts of safrole (0.63mg/Kg) have been shown to be cleared almost completely from the body within 24 hours in man & rats (Benedetti et al. 1977), the main urinary metabolite of safrole dosed in larger amounts is 1,2-dihydroxy-4-allylbenzene in both rats & man; 1’-hydroxysafrole and 3’-hydroxyisosafrole were also detected in the urine of the rat, but not of man (Benedetti et al. 1977). Jeurissen (2007) has identified the human P450 enzymes involved in the 1’-hydroxylation of safrole, where important roles for a series of enzymes via a series of in vitro experiments were postulated. Lifestyles factors which may lead to poor or extensive metaboliser phenotypes, which either reduce or increase the relative carcinogenicity risk, were discussed.

Also compelling evidence for humans, perhaps, lies with studies made of habitual quid chewers of betel & areca nut, where a constant body-loading of safrole may give rise to tumors over an extended time period. In particular, inflorescences of betel have been shown to contain relatively high (15mg/Kg) concentrations of safrole.


The classification of safrole as a Category 2 human carcinogen and the association of risk phrase R22-45-68 with the material seems disproportionate to the risks involved to humans from its traditional uses in spices, flavours, fragrances etc. Regulators appear to be forced by some unseen hand to deny the use of any traditional natural ingredients which have been shown to carry some health risks to susceptible animals at high doses, in an attempt to construct a clean, risk-free and largely synthetic-based world of their own. That is not the world that most of us wish to inhabit, and Cropwatch believes that many will ignore any restrictions which deny us the use of those familiar materials which we associate with our lives, our heritage & our traditions.


Benedetti M.S., Malnoë A. & Broillet A.L. (1977) "Absorption, metabolism and excretion of safrole in the rat and man." Toxicology 7(1), 69-83.

Bisset N. (1994) “Sassafras lignum.” in Herbal Drugs and Phytopharmaceuticals. Stuttgart, Germany: CRC Press (1994) pp 455–56

Boberg E.W., Miller E.C., Miller J.A., Poland A. & Liem A. (1983) “Strong evidence from studies with brachymorphic mice and pentachlorophenol that 1′-sulfooxysafrole is the major ultimate electrophilic and carcinogenic metabolite of 1′-hydroxysafrole in mouse liver.” Cancer Res. 43, 5163–5173.

Bolton J.L., Acay N.M. & Vukomanovic V. (1994) “Evidence that 4-allyl-o-quinones spontaneously rearrange to their more electrophilic quinone methides: potential bioactivation mechanism for the hepatocarcinogen safrole.” Chem. Res. Toxicol. 7, 443–450.

Choong Y.-M. & Lin H.-J. (2001) “A Rapid and Simple Gas Chromatographic Method for Direct Determination of Safrole in Soft Drinks.” Journal of Food and Drug Analysis 9(1), 27-32.

Dietz B. & Bolton J.L. (2007) "Botanical dietary supplements gone bad." Chem Res Toxicol. 20(4), 586–590.

Daimon H., Sawada S., Asakura S. & Sagami F. (1998) "In vivo genotoxicity and DNA adduct levels in the liver of rats treated with safrole." Carcinogenesis. 19(1), 141-6.

Daimon H., Sawada S., Asakura S., & Sagami F. (1997-1998) "Inhibition of sulfotransferase affecting in vivo genotoxicity and DNA adducts induced by safrole in rat liver." Teratog Carcinog Mutagen. 17(6), 327-337.

Daimon H., Sawada S., Asakura S. & Sagami F. (1997) "Analysis of cytogenetic effects and DNA adduct formation induced by safrole in Chinese hamster lung cells." Teratog Carcinog Mutagen. 17(1), 7-18.

Duke J. (2002)

Gold et al.- see Carcinogenic Potency Project @ www.potency.berkeley.edu/. (‘through Levy D.D. (undated) below.

Gupta K.P., van Golen K.L., Putman K.L. & Randerath K. (1993) "Formation and persistence of safrole-DNA adducts over a 10,000-fold dose range in mouse liver." Carcinogenesis 14, 1517–1521.

IARC (1976). “Some Naturally Occurring Substances. IARC Monographs on the Evaluation of Carcinogenic Risk of Chemicals to Humans, Vol. 10, 231-244. Lyon, France: International Agency for Research on Cancer.

IARC (1987). IARC Monographs on the Evaluation of the Carcinogenic Risk of chemicals to Humans: Overall Evaluations of Carcinogenicity: An Updating of IARC Monographs Volumes 1-42, Supplement 7, 51, 65.

Jeng J.H., Wang Y.J., Chang W.H., Wu H.L., Li C.H., Uang B.J., Kang J.J., Lee J.J., Hahn L.J., Lin B.R. & Chang M.C. (2004) "Reactive oxygen species are crucial for hydroxychavicol toxicity toward KB epithelial cells." Cell. Mol. Life Sci. 61, 83–96.

Jeurissen S.M.F. (2007) Bioactivation and genotoxicity of the herbal constituents safrole, estragole & methyleugenol. Thesis Wageningen University, The Netherlands (2007).

Levy D.D (undated) “Eugenol & the allylbenzenes: a case study on genotoxic risk.” – see http://www.gta-us.org/2008Presentations/Levy.pdf

Liu C.J., Chen C.L., Chang K.W., Chu C.H. & Liu T.Y. (2000) "Safrole in betel quid may be a risk factor for hepatocellular carcinoma: case report." CMAJ 162(3): 359–360.

Luo G. & Guenthner T.M. (1996). "Covalent binding to DNA in vitro of 2',3'-oxides derived from allylbenzene analogs.” Drug Metab. Dispos. 24, 1020–1027. [N.B. Erratum appears in Drug Metab Dispos 25(1), 131].

Lawrence B.M. (1990) “Progress in essential oils.” Perfumer & Flavorist 15, 63-69.

MAFF (1996) Food Surveillance Paper No. 48, Flavourings in Food, London, HMSO.

MAFF (1994) Food Surveillance Sheet No 30, June 1994 - Table . London HMSO.

Miller E.C., Miller J.A., Boberg E.W., Delclos K.B., Lai C.C., Fennell T.R., Wiseman R.W. & Liem A. (1985) “Sulfuric acid esters as ultimate electrophilic and carcinogenic metabolites of some alkenylbenzenes and aromatic amines in mouse liver.” Carcinog. Compr. Surv. 10, 93–107.

Patri G., Silano V. & Anton R. (2002) “Plants in Cosmetics.” Council of Europe Committee of Experts on Cosmetic Products, Council of Europe. 2002.

Randerath K., Putman K.L. & Randerath E. (1993) “Flavor constituents in cola drinks induce hepatic DNA adducts in adult and fetal mice.” Biochem. Biophys. Res. Commun. 192, 61–68.

Segelman A.B. (1976). JAMA 236, 477.

Stillwell, W. G. et al. (1974) “The metabolism of safrole and 2',3'-epoxysafrole in the rat and guinea pig.” Drug Metabolism & Deposition 2, 489-498.

Posted by Tony Burfield on September 18, 2009 in Essential Oils/Plant Extractions, Regulatory Issues, Safety/Toxicity | Permalink | Comments (1) | TrackBack

September 06, 2009

Melissa Oil & IFRA Policy (cont’d): The Further Details

by Tony Burfield, Cropwatch, 6th Sept 2009

For previous posts on this topic see here and here.


Those of us who have worked in the aroma trade for most of their working lives, have, at times, been highly skeptical of the knowledge & abilities of those unelected officials who would impose baffling & seemingly nonsensical regulations and codes of practice upon the trade. Sometimes we felt that we were being regulated by those who had little in-depth knowledge or experience of the subject - a feeling which has never really gone away.

Perhaps safety-orientated organisations like IFRA would have gained more credibility from some of us old-timers if they had more openly owned up to their previous errors. Yes, we accept that with improvements in experimental design and better techniques, many of IFRA’s earlier (nineteen seventies’) findings on ingredient toxicology are now suspect, or have been superseded. Most importantly, the failure to use rigorously purified aroma chemicals for toxicology testing by researchers reporting to RIFM, and the use of complex botanical materials from non-expertly identified botanical sources, has thrown large sections of IFRA’s previous toxicological findings into doubt since impurities and adulterants have often been responsible for adverse effects rather than the pure ingredients. From a personal standpoint, when you have been drenched in perfume & essential oils on a daily basis for 30-odd years, as many of us at the coalface have, you may feel some intuition (rightly or wrongly) for what aroma materials might be posing any handling risks. This is why many of us laughed openly over IFRA’s Quenching Hypothesis (now discredited). It is why we are still cynical over the disproportionate IFRA classifications of many materials which are supposed to be sensitising, according to the corporate-toxicological methodology involved in the QRA approach. But many of these ingredients indicated as sensitisers have failed to produce any significant numbers of adverse reactions amongst the end-users of fragranced cosmetic & household products in which they occur.

Melissa Oil: Lesson Learned

The curious case of the previous banning of Melissa oil as a fragrance ingredient by IFRA, gave Cropwatch an opportunity to explore IFRA’s ingredient policies in detail (see previous Cropwatch reports). In so many instances, a veil of secrecy obscures the detailed experimental facts on which IFRA/REXPAN ingredient status decisions are made. Following requests by Cropwatch, Robertet Grasse, to their immense credit, were willing to share their toxicological findings on Melissa oil testing, referred to in the RIFM data-base but otherwise not available to the general public. Subsequently we can now clearly see (in our opinion) that there was no good reason to ban Melissa oil from perfumery use in the first place, and a case for its continued restriction is heavily based on Robertet’s evidence, which was not comprehensive across a range of dosages, but based on a strategy to reduce costs. This involved contriving experiments at doses which were likely to produce a positive safety outcome, rather than the prospect of funding a more extensive range of tests proving its skin safety at higher dosages. That’s OK - we can easily deal with this, because it represents the truth. It’s just that IFRA didn’t previously reveal these particular facts about the economic restraints which have materially affected the testing strategies, for this particular ingredient.

Where do we go from here? It is apparent that we need an independent body to openly ascertain the facts about ‘pure’ toxicological science – as against the corporate-funded version of toxicology which we are forced to follow. It is also apparent from the mail that Cropwatch receives that there are other expert opinions out there – why must these individuals be sidelined and denied places on expert committees? Above all, Cropwatch is concerned that the low standards set out in many IFRA commercial standards may be rubber stamped & adopted by the EU Commission, as of course has happened previously, and which may come to be an increasing trend.

Melissa Oil – the Further Details

With a few minor punctuation changes, the reply from Catherine Gadras is set out below (we had asked for the exact botanical identification of the Melissa spp distilled for essential oil (since IFRA had failed to properly define it), and for its’ geographic origin & compositional details. We had further asked the Robertet team for any views on the presented HRIPT & EC3 data. We also had an exchange of mails with Michel Meneuvrier of SAPAD who provided the oil for testing (see below) & who confirmed that the Melissa plants distilled for oil were produced organically from Diois region plants.

Catherine writes:

As I mentioned below Melissa EO used for testing is Melissa officinalis subsp. officinalis L cultivated in the South East of France in the region of Di (Drôme). This genuine essential oil has been provided to us by the SAPAD (Société Anonyme des Plantes Arômatiques du Diois).
The sample was taken from the crop 2008. 7 to 8 levels of fresh leaves plus the flower part are used for the distillation.
Please find below the range of the main constituents provided to us by SAPAD and the composition of the sample used in the most recent tests. (See attached file: Melissa-EO Composition.pdf).[This file consists of the tables included an the end of the post – Ed.]
The crop results from the distillation of 3 cuts: one at the end of May and the two others from the beginning of July and at the end of August/beginning of September. The producer finds that the citral content is maximum in the third cut (greater than 50%) and that citronellal is below 10%.
2) Comments regarding safety data (HRIPT and EC3)
The LLNA has been made to determine a level of concentration at which one begins to observe induction of sensitisation. In our case 4500µg/cm2.
Considering the high cost of this EO (5 to 7 tons of fresh plants to
produce 1 Kg of essential oil) on one hand and the fact that we did not want to risk a positive reaction in the HRIPT, we have chosen this conservative 1470µg/cm2. 1470µg/cm2. This is more than adequate for perfumery use which is our business. It is quite possible that a higher safe limit for melissa EO exists but in my opinion it must be verified by testing my opinion it must be verified by testing.
PS: I take advantage of our e-mail exchanges to make some comments concerning the Cropwatch report on Melissa (page 3) that I found on internet :
I have 2 comments on this sentence below: :
"Under the draft proposals for IFRA’s 44th Amendment, melissa oil (which they describe as ‘genuine Melissa officinalis L.’) has been downgraded from an outright ban in fragrances, to a concentration restriction in the fragrance compound (as opposed to the finished cosmetic product). QRA data for melissa oil, which is categorised as a weak sensitiser, is presented by IFRA for the various established product categories, based on a No Expected Sensitization Induction Level (NESIL) of 1400µg/cm2."

1) Did you really mean "downgraded" ? My poor English would have expected "upgraded". (Cropwatch comments: downgraded from a negative position (a ban) but upgraded to more positive position (just a restriction) - it all depends on how you look at it!).

2) I confirm to you that the QRA limits are in finished consumer products and not in fragrance compounds.” (Cropwatch comments: on this latter point we stand corrected. Thank you Catherine!).

Addenda – Analysis Data received from Robertet.

Analysis of Melissa EO sample used in HRIPT test.







Cis Ocimène


Trans Ocimène


Para cymène


Methylheptenone 1


Octène 1 ol 3




Alpha copaene


Beta bourbonene


Linalool 1,38


Cis + Trans Isocitral


Beta Caryophyllene




Methyl geraniate






Geranyl acetate


Delta Cadinene or delta Amorphene 7






Isogeraniol (cis+trans)




Epoxydes de caryophyllene (cis+trans)




Muurolol T






Alpha Cadinol


Neric acid


Geranic acid


TOTAL 96,73

Information Stat from SAPAD

Mini %


Moyenne %

Escart Type %

Methyl heptenone















Neral +citronellol





Geranial + Geraniol





Caryophyllene beta





Posted by Tony Burfield on September 6, 2009 in Essential Oils/Plant Extractions, Perfumery, Regulatory Issues, Safety/Toxicity | Permalink | Comments (0) | TrackBack