I don’t need an alarm. Every morning, at six o’ clock precisely, my inbuilt body clock kicks me into life and has done so since I was a small boy.  Oh, how I wish it didn’t! In the early days I could be sharp as a tack straight from bed but, with advancing years, it seems to take far longer to get all systems functioning.

Not wishing to disturb Jan, I grope around in the dark to let the dogs out, stumbling over last night’s discarded bones as my eyes become accustomed to the early morning gloom. My daily routine has become quite fixed: feed Birdie, then the dogs, followed by the parakeets, and last the terrapins and wild birds.

Wisely muffled against the threat, I plunge my arm into Birdie’s cage. Squawk!  Spotting the smallest part of exposed flesh, twixt tea towel and oven glove, he plunges his beak into my wrist. Ouch!  That hurts! This is becoming a bit of a ritual.  Blood spurts profusely and, alerted by his screech, the dogs rush from the garden.  Encouraged by the commotion, Birdie proceeds gleefully to whip up a frenzy between Mick and Mungu. Mick lunges one way and Mung the other: they miss, and inadvertently nip me in both ankles. Barely awake, I writhe in pain.

Hobbling towards the shed, where their respective feeds are discretely stored, I try vainly to fend off the continuing skirmish around my legs.  Crikey! I’ve just fed the dogs’ biscuits to the terrapins. Still they don’t seem to mind too much, tucking voraciously into the Spillers Shapes. Totally disorientated, I dole out various seed mixes for parrot, parakeets, and wild birds. Meanwhile young Mick, the Imaal terrier, has his head in the parakeets’ bag of choice Baby Leaf Salad and Mungu, the Ridgeback, has made a fair start on tonight’s supper, which I have left carelessly on a nearby, Mung-high, table. Gosh, I shall get a right kicking when Jan descends!

Returning from the garden to the kitchen, I discover Birdie midst a hailstorm of wild bird seed.  Oh Lord!  That means that I have given his exotic ‘Fruity Parrot’ mix to the local blackbirds.  No wonder this morning’s dawn chorus sounds more joyful than usual: they are as high as kites.  By 8 o’clock, I’m exhausted!

A good response.
Following Maureen Plimley’s suggestion in last month’s Newsletter.....Why don’t your enlightened readers send in their suggestions as to what they think might be the three most potent and effective oils [against MRSA]?.....I am truly delighted by the response. Keep them coming!

Of those received so far, Tea Tree (Melaleuca alternifolia Cheel), Lemon (Citrus limon (L.) Burm. f.), and Manuka (Leptospermum scoparium Forster & Forster) feature quite large. Of Manuka, Sheila Wardle writes.....

I have successfully used Manuka for eight years in curing MRSA.  The first patient was in Manchester Royal Infirmary, when I used Manuka to wash down my stepfather and the room he was in, and in three days he was clear of MRSA.  Another ongoing patient has been cured three times since his stays in Royal Albert Edward in Wigan.  I use it successfully as a preventative, in conjunction with Tea Tree and Chamomile [unspecified], in unperfumed wet wipes.  Several people, including a one-year-old  baby, have not contracted MRSA by using these wipes.

However, by far the most mentioned suggestion is Thyme CT. Linalol (Thymus vulgaris L.). What does CT. mean?, I am often asked.

Thyme for discussion. 
In southern France, natural populations of T. vulgaris contain one or several of six genetically distinct chemical forms, or chemotypes (CT), that can be distinguished on the basis of the dominant monoterpene produced in glandular trichomes on the surface of the leaves and calyces.  Each of the six chemotypes, geraniol, a-terpineol, thujanol, linalol, carvacrol and thymol, is named after the dominant monoterpene in the essential oil.

The six monoterpenes have different molecular structures, with an important difference being the phenolic nature of carvacrol and thymol and the non-phenolic nature of the four other monoterpenes. Some of the chemotypes are discernible to the human nose in the field. This is particularly so for geraniol which often has a lemon smell and the two phenolics which have the characteristic thyme odour which makes them readily distinguishable from the four non-phenolic types.

The ecological role of these secondary compounds in thyme can be addressed under three headings: adaptation to the abiotic environment; competitive interactions with other plants; and chemical defence against herbivores and pathogens.

There are several pieces of evidence which indicate that the monoterpene variation may represent an adaptive strategy in relation to environmental variation. For example, based on bulk samples of plants from southern France, it is clear that phenolic chemotypes dominate thyme populations in hot dry sites close to the Mediterranean sea, whereas the non-phenolic chemotypes dominate sites further inland, particularly above 400 metres, i.e., in wetter, cooler climates. 

In the context of potential interactions with other species, volatile oils may have a negative “allelopathic” effect on the germination and growth of associated plant species and in this way reduce competition from other species. The potential allelopathic effect of monoterpenes and their role in structuring plant communities have been the centre of much interest. Bare zones under and around aromatic shrubs have been noticed in different aromatic species and much work on the effects of monoterpenes on the germination and growth of associated species has involved labiates in Mediterranean communities. In T. vulgaris all six of the oils cause an inhibition of seed germination to roughly 50 per cent that of seeds germinated in the absence of thyme monoterpenes.

As a defence against the strong pressure imposed on them by herbivores, parasites and pathogens, plants have evolved an immense diversity of chemical defences.  The more diverse, the partners at different trophic levels, the more important it may be to have a diverse, defence system. Herein lies a clue to the reason why there may be so many chemotypes in T. vulgaris: spatio-temporal variation in the abundance of different potential herbivores, parasites, etc. may lead to disruptive selection on chemical phenotype and thus contribute to the maintenance of several forms.

When I returned to the UK in the 1980s one of my first tasks was to mug up on malacology (the study of molluscs), in preparation for my role as an advisor to the burgeoning group of aspiring British snail farmers.  One of the first pieces of work that I consulted was that of  Gouyon et al. [Gouyon, P.H., Fort, P. and Caraux, G. (1983) Selection of seedlings of Thymus vulgaris by grazing slugs. J. Ecol., 71, 299-306].

These authors found marked variation between chemotypes in their palatability to slugs: thujanol was the least palatable and a-terpineol and carvacrol were the most palatable.  Later, years after I had left the world of slugs and snails, I was fascinated to read that snails have a preference for non-phenolics, particularly linalol, and a marked distaste for carvacrol and thymol.  What is more, the most deterrent monoterpene to snails, the phenolic carvacrol chemotype, caused snails fed on a diet of exclusively thyme plants of this chemotype to lose weight.

Interestingly, when linalol genotypes are at the seedling stage (1-3 months old) their leaves do not have a linalol phenotype, they have a phenolic phenotype, and only develop their “true” phenotype after this very young seedling stage. Thus, the chemotype most liked by snails may “hide” behind a less palatable phenotype during early seedling development - a stage in the life cycle that is likely to be critical for survival in the face of snail herbivory.

Who said plants aren’t smart?!

Judging the issue.
The first researcher who attributed antibacterial properties to thyme (without specifying the species) was a chap named Chamberlain in 1887, after observing the antibacterial effect of its “vapours” on Bacillus anthracis. Since then, numerous studies with essential oils of Thymus species have been carried out.  They were shown to inhibit a broad spectrum of bacteria.

Recently the antibacterial activity of thyme (Thymus vulgaris) oil against some important food-borne pathogens, namely Salmonella enteriditis, Eschericia coli, Staphylococcus aureus, Listeria monocytogenes, and Campylobacter jejuni, was tested.  The latter was found to be the most resistant of the bacteria investigated [Smithpalmer, A. et al. (1998) Antimicrobial properties of plant essential oils and essences against five important food-borne pathogens. Lett. Appl. Microbiol., 26, 118-122].

In another study [Osawa, K. et al. (1990) Studies on the antibacterial activity of plant extracts and their constituents against periodontophatic bacteria. Bull. Tokyo Dent. Coll., 31, 17-21] it was shown that the essential oil of thyme and especially its phenols, thymol and carvacrol, have antibacterial activity against periodontophatic bacteria including Actino-bacillus, Capnocytophaga, Fusobacterium, Eikenella, and Bacteroides species, and may therefore be suitable for plaque control, although few essential oils have been found to possess clinical efficacy [Marsh, P.D. (1992) Microbiological aspects of the control of plaque and gingivitis. J. Dent. Res., 71, 1431-1438].

Furthermore, the essential oil of thyme showed a wide antibacterial activity against micro-organisms that had developed resistance to antibiotics such as MRSA and vancomycin-resistant Enterococcus faecium [Nelson, R.R. (1997) In vitro activities of five plant essential oils against methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium. J. Antimicrob. Chemother., 40, 305-306].             
    
Several studies have focused on the antimicrobial activity of the essential oils of thyme in order to identify the responsible compounds. Thymol and carvacrol seem to play an outstanding role.  These terpene phenols join to the amine and hydroxylamine groups of the proteins of the bacterial membrane altering their permeability and resulting in the death of the bacteria [Juven, B.J. et al. (1994) Factors that interact with the antimicrobial action of thyme essential oil and its active constituents. J. Appl. Bacteriol., 76, 626-631].

Antibacterial activity was also observed for the aliphatic alcohols, especially geraniol, and ester components. A variety of activities was presented by the esters, in some cases they were more active than their corresponding free alcohols, but sometimes less active [Megalla, S.E. et al. (1980) A study of antimicrobial action of some essential oil constituents. Herba Pol., 26, 181-186].

As pointed out above, the essential oils of thyme, in general, fall into two main groups.  The first group contains those species in which phenols (thymol and carvacrol) predominate. These oils show remarkable antimicrobial activities. In the oils of the second group phenols are scarce or lacking, whereas other components, such as monoterpene hydrocarbons, non-phenolic oxygenated monoterpenes or even sesquiterpene hydrocarbons, predominate. Such oils usually demonstrate lower antimicrobial activities than those in the first group.

It will be interesting to discover what Val Edwards-Jones thinks.

Meanwhile, some years ago, Belgian researchers concluded that the thymol chemotype was the most active followed by the carvacrol and geraniol type; the linalol type showed similar activity to that of the geraniol type. The oils of the other chemotypes were much less active. [Lens-Lisbonne, C. et al. (1987) Methodes d’evaluation de l’activite antibacterienne des huiles essentielles: application aux essences de Thym et de cannelle. J. Pharm. Belg., 42, 297-302]

A concern for many?
Tea Tree oil is ‘unstable’ and ‘unsafe’, hollered the Independent on Sunday recently.

Tea Tree Oil (Melaleuca alternifolia Cheel) has been branded unsafe by the influential SCCP (The European Commission’s Scientific Committee on Consumer P roducts).  In an unusually blunt official opinion, the Committee stated....The sparse data available suggest that the use of undiluted Tea Tree oil as a commercial product is not safe. 

Because there was insufficient information for them to base a scientific opinion on, they have come to the only conclusion possible, based on the limited evidence available to them about skin irritation, sensitivity and allergy. The area of product safety that they are commenting on is the sensitization and allergenic potential of the oil.

This is nothing new and, in fact, COLIPA (European Cosmetic Industry Association) was prompted to comment in 2002.....

COLIPA recommends that Tea Tree oil should not be used in cosmetic products in a way that results in a concentration greater than 1% oil being applied to the body. When formulating Tea Tree oil in a cosmetic product, companies should consider that the sensitization potential increases if certain constituents of the oil become oxidized.  To reduce the formation of these oxidation products, manufacturers should consider the use of antioxidants and/or specific packaging to minimise exposure to light.

Still, I am extremely grateful to Ray Gransby, Technical Chairman of the Aromatherapy Trade Council, for the following rational and useful assessment of the current situation.....

SCCP have taken a fail-safe position until further information is available to them. They have considered that the evidence available to them suggests that the use of undiluted oil as a commercial product is not safe, that is not the same as saying that the oil is a danger to health.  This opinion will be reconsidered at the end of 2005 when they expect to have more information available to them.  In the meantime there is no suggestion that Tea Tree oil should be or will be banned for use either in cosmetics or other consumer products.

Examining the evidence.
As some will know, I have been associated with Tea Tree oil for almost thirty years and, therefore, feel entitled to the odd comment or two, albeit perhaps with tongue-in-cheek.

I would agree that, at room temperature and under the influence of light and oxygen, Tea Tree oil can degrade rapidly.  Research has shown that the contents of p-cymene and terpinen-4-ol considerably increase. And yet, for years, the Australian Tea Tree oil industry always packed in clear glass. What’s more, the bottle was invariably left on the window sill in baking sun. Also, Australians liked to apply “Nature’s Cure in a Bottle” neat. Nevertheless, I heard rarely of a case of sensitization: perhaps Australians have thicker skins than Europeans.

However, even in Europe, the prevalence for allergic contact dermatitis exhibits regional differences. In a Swiss study, only 7 of 1216 (0.6%) patch tested patients reacted positive to Tea Tree.  In a multicentre study with 11 dermatological departments in Austria and Germany 36 out of 3375 patients (1.1%) reacted to a 5% solution of Tea Tree oil.  All the same, I do wonder if there are not far more adverse reactions to fusion cooking.

Still, it is a serious matter and I have just heard, this very minute, from Dr. Roslyn Prinsley, Rural Industries Research and Development Corporation, Australia, that the Australian Tea Tree Oil Industry is very concerned about the SCCP Opinion on Tea Tree Oil and has formed a special group to examine the responses and actions that need to be taken. The Chair of this Sub-Committee of ATTIA (Australian Tea Tree Industry Association) is Christopher Dean of TPHealth (which I remember rather better as Thursday Plantation).  I am confident that Chris will give it his best shot.

Almost a decade ago, Australian researchers concluded that the elimination of the allergenic fraction in tea tree oils would be desirable [Southwell, I.A. et al. (1997) Skin irritancy of tea tree. J. Essent. Oil Res., 9, 47-52].  Preliminary allergen investigations had suggested that the sesquiterpene hydrocarbon fraction of tea tree was the most allergenic. 

This was consistent with earlier research, which had found that aromadendrene, one of the major sesquiterpene hydrocarbons of tea tree oil, was a major allergen.  However, both trials were small. 
To eliminate the allergenic fraction, three possible methods involving either processing (selection of steam distillation conditions), rectification (fractional distillation) or genetic selection could be used.

In 1989, research had shown that the oil from the first 30 minutes of a laboratory hydro-distillation gave 63% of an oil containing only 25-33% of the sesquiterpene hydrocarbons that were present in the later 30-90 minute fraction which constituted the remaining 37% of the oil.  Thus, manipulation of distillation time during processing may be a way of minimizing the concentration of the allergenic fraction, and rectification would easily remove monoterpenoids (including terpinen-4-ol, the active ingredient) from the sesquiterpenoids.  The selection of genotypes low in sesquiterpenes could also minimize allergen content.

However, I recall that when I was last in Australia, just before the publication of this report, many growers were already aware of its contents and were ‘pushing’ the sale of Melaleuca linariifolia Smith, because investigations had revealed that the oil has a lower level of sesquiterpenes. I added it immediately to our List, but few seemed interested.

Nevetheless, as the SCCP admits, it is not fully understood which of the constituents are the real allergens and, therefore, it is difficult to know which species of  Melaleuca would suit: certainly there are several very low sesquiterpenoid Melaleuca oils available.      

Nut allergies discussed.
If you haven’t already read it, do get hold of January’s edition of CAM.  In it, there is a most interesting article by Philippa Buck, registered pharmacist and aromatherapist with a special interest in skin diseases, and Janetta Bensouilah, Course Director at Raworth College, about Nut allergies in children - Are massage oils safe? Even small doses of nut proteins found in refined oils may sensitize children through the skin.  Philippa and Janetta review the facts and suggest a safe course for practitioners using carrier oils.    
  
They discovered that a review of massage and aromatherapy literature reveals a surprising lack of detailed information on this subject. They found no discussion about the possibility of sensitizing an infant or child to such allergens through repeated skin application of nut oils.

In view of the increasing prevalence of childhood allergy and the potentially fatal results, they believe that body-workers should be very cautious in using nut and sesame seed oils.

Accompanying the article is a Table of recognized plant allergens, extracted in part from the International Union of Immunological Societies, Allergen Nomenclature Sub-committee website <http://www.allergen.org>.  Frankly, some of them quite surprised me.....

Cashew nut, Peanut, Brazil nut, Chestnut, Hazelnut, Soy, Sunflower, Black Walnut, English Walnut, Macadamia nut, Olive, Avocado, Pine nut, Apricot, Sweet Almond, Peach, Castor Bean, and Sesame.

Interestingly, Sweet Almond is not listed on this particular website but there have been numerous reports of allergic reactions to this oil.  All the same, Soy, Sunflower and Olive would not have leaped immediately to mind. Still, having reviewed this list, I began to wonder which oils they would consider suitable alternatives to nut and seed oils for use in bodywork.

Borage, Fractionated Coconut oil, Evening Primrose oil, Grapeseed, Jojoba, Safflower.

Grapeseed is perhaps the least therapeutically useful, as it is so highly refined that it has little if any nutritional value to the skin; however, it is considered a safe hypoallergenic medium.

Fractionated Coconut oil has very few reported instances of allergy and where this has occurred it has been attributed to cross-reactivity with walnut [Crevel, R.W.R. et al. (2000) Allergenicity of refined vegetable oils. Food and Chemical Toxicology, 38, 385-93]. They advise that it provides an alternative for occasional use in nut-allergic children.

The other oils which are suggested have no reported cases of allergy associated with their use and are not obtained from known plant allergens and, therefore at the present time, they think them safe, therapeutic alternatives to nut oils.  What do you think?

An old favourite returns.
Although I have not yet had the opportunity to review a copy, I am sure that if it is a patch on the original edition it will have a place on most bookshelves: Aromatherapy for Babies and Children by Penny and Shirley Price.

According to my crib sheet, this brand new Riverhead Publishing title is written with both professional and lay aromatherapists in mind.  It is designed to help them use their knowledge and skills to heal and soothe babies and children.

Daughter and mother, who are both distinguished aromatherapists, explore the character and therapeutic value of different essential oils and blends, and give details and practical advice on baby and child massage.

The 200 page text also explains how aromatherapy massage can help a child gain emotional and physical health, and how it helps in the early bonding process.  It includes which oils are safe, which ailments and behavioural problems they can assist, recipes for blends, and fully illustrated massage techniques. 
 
Something to celebrate!
The International Federation of Aromatherapists is the longest established charitable international organization representing professional aromatherapists in the United Kingdom and abroad.  Some might say that it is the original and the best!

IFA 20th Anniversary Conference
Saturday, 11th June & Sunday, 12th June, 2005
10.00am to 4.30pm
Hamilton House, Mabledon Place, London WC1H 9BD
ALL welcome
To celebrate 20 years of international achievements in the World of Aromatherapy.

The weekend will include an exciting progamme of speakers, presentations and workshops. Already confirmed are leading speakers Dr. Christine Page, whose book Frontiers of Health is a classic for those seeking harmony of the body, spirit and mind, and Valerie Worwood, the author of the trilogy, Fragrant Pharmacy, Fragrant Mind and Fragrant Heavens.  Surely, two ladies not to be missed!  Other speakers will be announced shortly.

It seems pretty good value too, and you get up to 12 CPD points accredited for attendance. 

IFA members £80 per day, £150 for both days
Non-IFA members £90 per day, £170 for both days 
Discount available before 31st March. 

As places are limited, you are strongly advised to book as soon as possible.      

Booking Hotline: 0208 742 2605

Finally.....
I am certain that I read somewhere that Government scientists are proposing a new method to combat the spread of MRSA and other infections in hospitals.....Cashew nut oil!

A panel, ordered by the Health Secretary to find ways to curb MRSA, says the oil’s natural qualities could make it an ideal disinfectant to help staff spreading the disease. Apparently, it is one of seven proposals from the panel. Anyone know anything more?

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