What a wonderful day!  I have just returned from a quick trip in Jan's car to nearby Chipping Norton.  Being a somewhat more modern model than my customary transport, it is  equipped with sophisticated gizmos like a thermometer.  A most pleasant 28ºC.  Long may it last. I note that when the sun shines sales drop but, being Britain, I have no worries.  Sun and warmth are such wonderful therapies and global  warming has some way to go yet!

In contrast, I had spoken to John Kerr earlier in the morning, to finalise details about the  forthcoming launch of Aromatherapy Today, who was sitting  shivering in Sydney, Australia. Did I feel smug?!  In fact, it can get distinctly chilly down under during the winter.  John was fairly bubbling with  enthusiasm and promised a cracking first issue for us here in the UK.  For those, like me, who miss Aromatherapy Quarterly it could prove a worthy substitute.

Even earlier, 6a.m.  to be precise, I had been checking out a theory expounded in Tradescant's Diary in the July edition of The Garden.  Apparently English and French moles keep different timetables.  While French moles work a six-hour  cycle, checking the earthworks at six, noon and six, ours do four-hour shifts, more like naval watches.  The times to meet face to face with an English mole  are eight in the morning, noon and just before tea at four o'clock.  However having kept silent vigil at the appointed hour for several mornings without success, I determined to discover if I had not a furry foreigner beneath my sacred turf.  Well, if I have, he didn't turn up either.  An Australian mole  perhaps?  Now that would be a chronometric challenge!  Meanwhile the mounds continue to multiply.

Lime Oils  distinguished.
A recent cover story in The Sunday Times Magazine prompted me to look more closely at this Citrus member of the Rutaceae, a large family containing 130 genera in seven subfamilies, with  the Aurantioideae important oil and fruit producers.  Within the Aurantioidiae  are the Citrae which contain Citrus (16spp.).

Extracted from the recently published The Africa House by Christina Lamb, I was interested to discover why,  in the 1920s, an English army officer had built his very own Xanadu, a lavish English country mansion in the heart of the African jungle, embossing over the door a coat of arms with the motto Spero meliora (I hope for better things).   Careful reading of the tightly-set script revealed that Lt.Col. Stewart  Gore-Brown, retracing Livingstone's last footsteps in the opposite direction, had stumbled upon Shiwa Ngandu, the Lake of the Royal Crocodiles, in the former Northern Rhodesia (Zambia), and simply noted in his diary: Happy!

Here, 400 miles  trek through harsh terrain and crocodile-infested swamps from the nearest  railway station at Ndola, he established his Shangri-la and started to farm.   The rice crop was a disaster; the mealies and groundnuts went the same way and plans to keep cattle were aborted by the discovery of tsetse fly on the estate.   After repeated crop failures, he turned to essential oil production.  However,  by 1947, his annual income from essential oil exports had plummeted from £6,000  during 1941-46 to £264 and in 1954 he closed the oil distillery after disease infected all his 10,000 lime trees and seedlings.  This got me thinking.  Which lime?

Lime probably  originated in northern India and adjacent areas of Burma, and is widely grown in India where there are numerous local cultivars.  Limes are generally classified in two groups.  One contains Key, West Indian and Mexican cultivars whose fruit is small, round, moderately seedy and highly polyembryonic, with thin peel, smooth, greenish flesh and a citric acid content of 6.5-8.0%.  The other  contains Persian types whose fruit is larger, seedless, less acid and mainly  sold as fresh limes or lime juice.  Persian lime oils are considered to be flatter or weaker than Key lime oils, although both are offered indiscriminately as lime oil.  Certain authorities include under Citrus aurantifolia Swingle only the Key lime group, with the Persian group classified as Citrus latifolia Tanaka.

The essential oil  is obtained mainly from the peel.  The Persian group has a peel content of 0.3-0.4%, and Key limes nearly twice this, but fruit from selected Key lime  trees can have up to 1.5%.  As noted there are basically two types of lime, whose fruit is sweet and sour, and the latter is the main raw material for oil production.  Within the sour lime category there are cultivars whose oils  differ, and oil obtained by various methods also differs.  Therefore it is  necessary when comparing lime oils that not only botanical and geographical  origin be stated, but also production method.

Distilled lime oil is obtained by two basic methods: distilling a slurry of crushed  whole limes and finely chopped peel, or distilling juice from fruit pressing.   In the latter, juice suitable for canning is drawn off after a storage period and the residue of juice, pulp and dissolved oil is steam distilled.  An improved technique combines steam and vacuum low-temperature distillation, which  allows direct use of halved, de-juiced fruits without adding water; this reduces the danger of affecting oil flavour, inherent in treating a highly acid mixture  with boiling water.  The oil is water-white to pale yellow, and a fresh, good-quality oil will be pale rather than coloured; the odour is sharp limey-lemon, becoming increasingly sweet, less limey and more orangy on dry-out.  Distilled oil generally has poor tenacity and is considered inferior to expressed oil.  It has less citral, beta-pinene and gamma-terpinene, but more p-cymene, terpinen-4-ol and alpha-terpineol than expressed oil, and a  more pronounced terpene-like odour.  Lack of the non-volatile coumarins increases oxidation risk during storage.The oil is seldom  adulterated since it is relatively cheap and easily available.

Cold-pressed and distilled oils are sufficiently different to preclude general interchangeability and although some users are not particular with regard to source, others have  very strong preferences.  The flavour and odour of pressed oils depends upon their oxygenated and hydrocarbon constituents.  Citral, certain  aliphatic aldehydes, linalool, geraniol, terpineol, borneol and their esters produce characteristic notes; while the terpenes, especially limonene and dipentene, impart the freshness.

Cold-pressed oils are generally highly coloured, distilled oils are normally  clear, and as noted above there is also a basic difference in characteristics  and composition.  Cold-pressed oils contain 12-15% wax, distilled oils are wax-free.  Cold-pressed oil suffered a severe setback during the mid-1970s when it was discovered that coumarins could have phototoxic effects on human skin.  Distilled oil presented no  problem as coumarins are not carried over during distillation.  Rectification of cold-pressed oil to wholly or partially remove coumarins largely overcomes the problem, but inevitably increases the cost.

Expressed oil was formerly obtained by manual ecuelling; a fascinating process worthy  of mention, since machines have developed from it.  The écuelle à piquer (literally a bowl for pricking) was a funnel made of tinned copper with a hollow handle.  The upper saucerlike part had on its surface numerous metal pins about 0.5cm long.  Fruits were placed in the bowl, which was rotated by hand.  The oils glands were punctured and the oil-and-water mixture collected in the handle. 

Today a mechanical method presses whole fruits, and the extract is then passed through high-speed centrifugues quickly to separate the oil.  Although this is technically an expressed oil, its characteristics, flavour and odour differ from  ecuelled oil, and they are not always interchangeable.  Expressed oil is medium yellow to dark green and may be so dark as to render determination of  optical rotation impossible.  Fresh oil has a rich sweet odour, lemon-like but more mellow and nearer that of crushed limes but not lime juice.

Limette oil  is obtained from a species of sweet lime (Citrus limetta Risso) cultivated mainly in southern Italy.  The oil is available in  very small quantities on demand and is almost identical to lemon in odour, with a citral content around 6%.

Lime Oils and  Aromatherapy.
Citrus aurantifolia (Bitter Lime) is considered antirheumatic, antiscorbutic, anticoagulant, antiseptic, antispasmodic, possibly antiviral, bactericidal, febrifugue and tonic-restorative.  Also a useful deodorant and astringent, care should be taken however to ensure that it is bergapten-free: otherwise it must be considered a potential dermal irritant and sensitizer as well as being phototoxic.  Useful for the treatment of coughs and cold congestion, it has a reputation as a muscle tonic and for easing inflammation.  Antiviral claims are not yet proven, but there is  evidence that it can assist with sore throat and influenza. Definitely uplifting  and stimulating, it is refreshing and restorative and could be useful in treating alcoholism.  Similarly, it should dispel apathy and relieve depression  and listlessness.

Citrus latifolia (Persian Lime) is considered antiseptic, sedative and stomachic, and  especially effective against airborne bacteria.  There is limited evidence that it could assist with dyspepsia and could be useful for the treatment of anxiety,  nervousness and insomnia.  No doubt effective for the treatment of acne and boils, it must be treated with care as phototoxic reactions have been  reported; particularly with the use of older oxidised oils or those with a high d-limonene content.

Citrus limetta (Sweet Lime) appears antispasmodic, antimicrobial and possibly  antiviral.  Most evidence suggests that it can be used as for Bitter  Lime.

Aromatherapy?
At the beginning of  July I attended the Complementary Therapy Day at Bridgwater College, hosted by Taunton & Somerset NHS Trust with RCN South West.  What a delightful group of ladies!  Not only was I the only male in attendance but I was also scheduled to speak about aromatherapy, a subject about which I am very reluctant to comment in public not being an aromatherapist.  Still, with a little research, I thought that I could just about hack it!  First off, I  thought it a good idea to check what others had said before me. 

One author commented: One of the differences between the aromatherapy and perfumery  communities lies in their attitude towards the perfume stimuli.  Aromatherapists  ascribe a special role to natural oils, yet at the same time stress the potential toxicity of synthetic materials.  This was obviously a reference to Robert Tisserand who, back in 1979, had cogently summarized the position of aromatherapists: Why natural oils?  Why not anything that smells nice whether it is natural or synthetic?  The answer is simply that synthetic or  inorganic substances do not contain any life force; they are not dynamic....Everything is made of chemicals, but organic substances like  essential oils have a structure which only Mother Nature can put together.  They have a life force, an additional impulse which can only be found in living things.

I recollect that many considered his brave summation to be an example of latter-day vitalism (The doctrine that life originates in a vital principle distinct from  chemical and other physical forces), a belief that impeded the development  of biological chemistry until, beginning with Wohler's synthesis of urea in 1828 and continuing through the demonstration of enzymatic activity in pure protein  by Sumner and others in the 1920s, it became evident that the chemical  substances of living tissue were in all physiological respects identical to the  same molecules synthesized in the laboratory.

Scientists were  also quick to point out that the dynamic activity which is characteristic of cellular living processes and which is esteemed by practitioners of aromatherapy is not a property of the constituent molecules of the cell.  The metabolic activity comes about from the specific organization of and specific interactions  between these molecules both in time and space.  The thermodynamic and  physico-chemical principles involved in these interactions are well understood and present understanding permits impressive technical developments such as the  synthesis of novel enzymes, the fabrication of synthetic genes and the construction of active membrane systems.  It was even suggested that  aromatherapists should perhaps use living plant tissues, since these have demonstrable dynamic and metabolic activities, rather than the oils extracted  from the tissues.  And as for the term essential, a word often taken to denote some vitalistic property of the oils which is presumed to be lacking  from synthetic materials, the oils contain secondary rather than primary  metabolites and are not essential for the "life" of living cells.

Robert soldiered on  bravely concluding, at the end of his lecture to the 1st International  Conference on Psychology of Perfumery in 1986, that there was a difference between aromatherapy, defined as a therapy using natural oils, and mood fragrances, which are largely based on aromatic chemicals, just like any other perfume, and urged that a distinction should be maintained between serious forms of medicine and commercial mood products or otherwise the term aromatherapy would be in danger of being overstretched as different people  attempted to apply it to all categories of fragrance application.

Did he realise however that it was already probably too late?  His book The Art of Aromatherapy, published in 1977, had already introduced the concepts of  aromatherapy to a wider audience in English- and German-speaking societies.  Its popular style had made aromatherapy accessible to everyone and removed it from its isolation as an appendix to medical academia, as it had been in the days of René-Maurice Gattefossé and Jean Valnet.  Massage therapists and laypeople entered the field in growing numbers and quickly turned it into an  economic reality.  The bandwagon had begun to roll!

The non-academic character of aromatherapy in Britain is probably a main reason why it is confronted with a certain antagonism from the conventional establishment (Dr. Kurt Schnaubelt, Medical Aromatherapy).

Dr. Schnaubelt comments further: While the British developments are equated by many with the development of aromatherapy in general, sometimes sharp differences exist in the course aromatherapy has taken in different regions and cultures.  The direction aromatherapy took in France remained scientific and medical, yet ultimately alternative.  Germany developed its own rather esoteric aromatherapy  scene, and Australia had its own British-influenced brand of new therapy.  But it was in Britain that aromatherapy flourished as a form of massage therapy and ultimately was characterized as a complementarymodality.

Much the wiser, and  aware of Section 39 of the United Kingdom Central Council's (UKCC), the disciplinary body set up under the Nurses, Midwives and  Health Visitors Act 1992,document Standards for the Administration of  Medicines which states that practitioners who use substances such as essential oils must recognise the importance of consent (from the client,  which must be difficult when extremely elderly or with learning difficulties.  I believe that the permission of relatives is not  sufficient) and are also accountable for their professional practice and must be able to apply their specialist knowledge and skill, I concluded that my audience would know far more about aromatherapy than I do and so restricted myself to ensuring that they were familiar with the substances used, as required by Section 38.  You're correct: I hacked it!

By the way I note  that Aromascan, which makes odour sensors, is changing its name to Osmetech - derived from Osme, the Greek for smell - to reflect its change  in direction.  It is now to concentrate on applying its technology to detecting  microorganisms, focusing on two healthcare applications: identifying urinary tract infections and early recognition of pneumonia.  Somehow it strikes me as  somewhat ironic!

Freedom to Choose March Flops!

Consumers failed to  turn out in large numbers for June's Freedom to Choose March held in Hyde Park.   Despite claims by the organiser that between 1,000 and 2,000 people turned up, estimates from many who attended put the number at no more than 500.  Despite  the extremely late notice, this was still a most disappointing response.  The  march featured six speakers, including Brian Iddon M.P. and health writer Leslie Kenton.  A petition against proposals as detailed in consultation document MLX  249 were also taken to 10 Downing Street.  Do people really care, I wonder?

They should, because The Government appears to be pushing ahead with the proposed legislation  despite receiving an estimated 300,000 signatures on health food trade petitions  complaining about the move.  According to Penny Viner, director of the Health  Food Manufactuers Association, the latest word from the Medicines Control  Agency is that MLX249 could still become law this summer, but  autumn is more likely. 

Still it is also worth noting the comments made by Michael McIntyre, Chairman of the  European Herbal Practitioners Association, in a recent letter to Natural Product News: May I make one more point?  It seems that many in the UK are focusing on an apparent danger posed to natural products by the MCA's publication of  MLX249......[However] it does seem vital that we all realise that the major threat to herbal medicines [and essential oils] is likely to come  from the EU rather than the MCA......Our energies need to be directed to campaigning for a Third Way in Europe, and we would be well advised to keep our powder dry for the critical battle soon to come!  I agree.

Noted not  Read....Yet!
Skimming my usual list of monthly abstracts I noted a couple on Tea Tree(Melaleuca alternifolia Cheel), the full reports of which  those eager beavers amongst you might wish to read before me.  Tea Tree has been  widely used in modern medicine and cosmetics in recent years but, although there  are clinical data to show the beneficial effects (antiseptic, antimicrobial, antioxidative) of this essential oil, dose response studies are lacking.  R. Saller et al. in their paper, Pharmaceutical and medicinal aspects of Australian tea tree oil (Phytomedicine (1998) 5 (6) 489-495),  present and discuss the history of use, chemical constituents, effects and efficacy, clinical studies, experimental uses, uses in cosmetics,  pharmacokinetic properties, adverse reactions, toxicology and doses of tea tree  oil.  Also Carson & Riley, continuing their indefatigable studies of Tea Tree, determined the activity of the oil against bacterial clinical isolates and  commensal lactobacilli. Interestingly the lactobacilli were appreciably more resistant than the organisms associated with bacterial vaginosis (Hammer, K.A., Carson, C.F., Riley, T.V.  In vitro susceptibilities of lactobacilli and organisms associated with bacterial vaginosis to Melaleuca alternifolia.  Antimicrobial Agents and Chemotherapy (1999) 43 (1) 196).   

Setting the  Standard.
I am often asked who sets the standard for essential oils.  The International Standards Organisation created ISO/TC-54 , Essential Oils, in  1947 as one of the first ISO Technical Committees.  This work has been recognized for many years, with the publication of an excellent set of standards, but is little known by aromatherapists.

However the use of international standards by companies has not gone as far as it should because much of the essential oil trade, of which aromatherapy is only a minute part, is made up of specialities; essential oils partially modified to achieve certain  customer demands such as low price or consistent quality, independent of variations in harvests.  These requirements are not necessarily inherent in the original essential oils.  This troubling point has difficult solutions.   Owing to environmental requirements, new standards have to be prepared on areas such as residual solvents, pesticides and environmental problems. However  pesticide analysis requires expensive and difficult checks.

Authenticity problems have now been resolved in certain circumstances, using chromatography with chiral columns, IRMS or NMR, and new essential oil adulteration problems have been detected.  Standards have to consider, in some cases, the determination of the origin of the essential oil.  Standards also have to consider determination of components limited by legislation on areas regarding  health.  ISO/DIS 7358, oils of bergamot, lemon, citron and lime,  determination of bergaptene content by HPLC or ISO 7357, oil of calamus,  determination of cis-beta-asarone content by GC, are good illustrations of  this.

Aromatherapy requires new standards.  The use of pure essential oils where direct smelling of  the product is involved can create new problems due to the possible presence of pesticides or products intended only for limited use.  How many aromatherapists, I wonder, have thought seriously about this?  In other more  traditional applications, because of the usual dilution employed, the use of these essential oils does not present any severe risks to users.

However we can rest  assured that, with the above-mentioned points in mind, the demand for new international standards in the field of essential oils will continue to grow.   As Carlos Ibáñez, Chairman ISO/TC-54, Essential Oils, says: We need such standards to facilitate world trade and to promote the quality of products.  Other major concerns include the health of the consumers, the safety of the  products and the industrial processes, and the application of advanced  industrial technology by less-developed countries who will turn to the work of  ISO/TC-54 to help the sector develop.

Finally
We have some most  interesting essential oils just arrived from Lebanon.  Although most have familiar names, some are very different in their chemical composition.  Do ask  for a GC/MS analysis with which to compare your oils from more traditional origins.  No fear here about pesticide problems.  Several have already acclaimed  them to be especially vital!

On that note, I am off to commence the afternoon mole watch!

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