Encyclopedia of Essential Oils: The complete guide to the use of aromatic oils in aromatherapy, herbalism, health and well-being.

Ancient Civilizations

Aromatic plants and oils have been used for thousands of years, as incense, perfumes and cosmetics and for their medical and culinary applications. Their ritual use constituted an integral part of the tradition in most early cultures, where their religious and therapeutic roles became inextricably intertwined. This type of practice is still in evidence: for example, in the East, sprigs of juniper are burnt in Tibetan temples as a form of purification; in the West, frankincense is used during the Roman Catholic mass.

In the ancient civilizations, perfumes were used as an expression of the animist and cosmic conceptions, responding above all to the exigencies of a cult … associated at first with theophanies and incantations, the perfumes made by fumigation, libation and ablution, grew directly out of the ritual, and became an element in the art of therapy.¹

The Vedic literature of India dating from around 2000 BC, lists over 700 substances including cinnamon, spikenard, ginger, myrrh, coriander and sandalwood. But aromatics were considered to be more than just perfumes; in the Indo-Aryan tongue, ‘atar’ means smoke, wind, odour and essence, and the Rig Veda codifies their use for both liturgical and therapeutic purposes. The manner in which it is written reflects a spiritual and philosophical outlook, in which humanity is seen as a part of nature, and the handling of herbs as a sacred task: ‘Simples, you who have existed for so long, even before the Gods were born, I want to understand your seven hundred secrets! … Come, you wise plants, heal this patient for me’.² Their understanding of plant lore developed into the traditional Indian or Ayurvedic system of medicine, which has enjoyed an unbroken transmission up to the present day.

The Chinese also have an ancient herbal tradition which accompanies the practice of acupuncture, the earliest records being in the Yellow Emperor’s Book of Internal Medicine dating from more than 2000 years BC. Among the remedies are several aromatics such as opium and ginger which, apart from their therapeutic applications, are known to have been utilized for religious purposes since the earliest times, as in the Li-ki and Tcheou-Li ceremonies. Borneo camphor is still used extensively in China today for ritual purposes. But perhaps the most famous and richest associations concerning the first aromatic materials are those surrounding the ancient Egyptian civilization. Papyrus manuscripts dating back to the reign of Khufu, around 2800 BC, record the use of many medicinal herbs, while another papyrus written about 2000 BC speaks of ‘fine oils and choice perfumes, and the incense of temples, whereby every god is gladdened’.³ Aromatic gums and oils such as cedar and myrrh were employed in the embalming process, the remains of which are still detectable thousands of years later, along with traces of scented unguents and oils such as styrax and frankincense contained in a number of ornate jars and cosmetic pots found in the tombs. The complete iconography covering the process of preparation for such oils, balsams and fermented liqueurs was preserved in stone inscriptions by the people of the Nile valley. The Egyptians were, in fact, experts of cosmetology and renowned for their herbal preparations and ointments. One such remedy was known as ‘kyphi’; a mixture of sixteen different ingredients which could be used as an incense, a perfume or taken internally as a medicine. It was said to be antiseptic, balsamic, soothing and an antidote to poison which, according to Plutarch, could lull one to sleep, allay anxieties and brighten dreams.

Treasures from the East

Natural aromatics and perfume materials constituted one of the earliest trade items of the ancient world, being rare and highly prized. When the Jewish people began their exodus from Egypt to Israel around 1240 BC, they took with them many precious gums and oils together with knowledge of their use. On their journey, according to the Book of Exodus, the Lord transmitted to Moses the formula for a special anointing oil, which included myrrh, cinnamon, calamus, cassia and olive oil among its ingredients. This holy oil was used to consecrate Aaron and his sons into priesthood, which continued from generation to generation. Frankincense and myrrh, as treasures from the East, were offered to Jesus at his birth.

The Phoenician merchants also exported their scented oils and gums to the Arabian peninsula and gradually throughout the Mediterranean region, particularly Greece and Rome. They introduced the West to the riches of the Orient: they brought camphor from China, cinnamon from India, gums from Arabia and rose from Syria, always ensuring that they kept their trading routes a closely guarded secret.

The Greeks especially learnt a great deal from the Egyptians; Herodotus and Democrates, who visited Egypt during the fifth century BC, were later to transmit what they had learnt about perfumery and natural therapeutics. Herodotus was the first to record the method of distillation of turpentine, in about 425 BC, as well as furnishing the first information about perfumes and numerous other details regarding odorous materials. Dioscorides made a detailed study of the sources and uses of plants and aromatics employed by the Greeks and Romans which he compiled into a five-volume materia medica, known as the Herbarius.

‘Lentisco del Peru’ (Mastic Tree) from Durante’s Herbario Nuovo, 1585. Gums and oils were regarded as highly prized trade items throughout the Mediterranean region

Hippocrates who was born in Greece about 460 BC and universally revered as the ‘father of medicine’, also prescribed perfumed fumigations and fomentations; indeed ‘from Greek medical practice there is derived the term ‘iatralypte’, from the physician who cured by the use of aromatic unctions’.⁴ One of the most famous of these Greek preparations, made from myrrh, cinnamon and cassia, was called ‘megaleion’ after its creator Megallus. Like the Egyptian ‘kyphi’, it could be used both as a perfume and as a remedy for skin inflammation and battle wounds.

The Romans were even more lavish in their use of perfumes and aromatic oils than the Greeks. They used three kinds of perfumes: ‘ladysmata’, solid unguents; ‘stymmata’, scented oils; and ‘diapasmata’, powdered perfumes. They were used to fragrance their hair, their bodies, their clothes and beds; large amounts of scented oil were used for massage after bathing. With the fall of the Roman Empire and the advent of Christianity, many of the Roman physicians fled to Constantinople taking the books of Galen, Hippocrates and Dioscorides with them. These great Graeco-Roman works were translated into Persian, Arabic and other languages, and at the end of the Byzantine Empire, their knowledge passed on to the Arab world. Europe, meanwhile, entered the so-called Dark Ages.

Alchemy

Between the seventh and thirteenth centuries the Arabs produced many great men of science, among them Avicenna (AD 980‒1037). This highly gifted physician and scholar wrote over a hundred books in his lifetime, one of which was devoted entirely to the flower most cherished by Islam, the rose. Among his discoveries, he has been credited with the invention of the refrigerated coil, a breakthrough in the art of distillation, which he used to produce pure essential oils and aromatic water. However, in 1975 Dr Paolo Rovesti led an archaeological expedition to Pakistan to investigate the ancient Indus Valley civilization. There, in the museum of Taxila at the foot of the Himalayas, he found a perfectly preserved distillation apparatus made of terracotta. The presence of perfume containers also exhibited in the museum dating from the same period, about 3000 BC, confirmed its use for the preparation of aromatic oils. This discovery suggests that the Arabs simply revived or improved upon a process that had been known for over 4000 years!

Rose water became one of the most popular scents and came to the West at the time of the Crusades, along with other exotic essences, and the method of distillation. By the thirteenth century, the ‘perfumes of Arabia’ were famous throughout Europe. During the Middle Ages, floors were strewn with aromatic plants and little herbal bouquets were carried as a protection against plague and other infectious diseases. Gradually the Europeans, lacking the gum-yielding trees of the Orient, began to experiment with their own native herbs such as lavender, sage and rosemary. By the sixteenth century lavender water and essential oils known as ‘chymical oils’ could be bought from the apothecary, and, following the invention of printing, the period 1470 to 1670 saw the publication of many herbals such as the Crete Herball published in 1526, some of which included illustrations of the retorts and stills used for the extraction of volatile oils.

In the hands of the philosophers, the art of distillation was employed in the practice of alchemy, the hermetic pursuit dedicated to the transformation of base metals into gold, the gross into the subtle. It was primarily a religious quest in which the various stages of the distillation process were equated with stages of an inner psychic transmutation, ‘dissolution and coagulation’: separation (black, lead), extraction (white, quicksilver), fusion (red, sulphur) and finally sublimation (gold or ‘lapis’). In the same way that aromatic material could be distilled to produce a pure and potent essence, so could the human emotions be refined and concentrated to reveal their valuable fruit, or true nature. In this context, volatile oils can be equated with the purified human psyche or ‘quintessence’ of the alchemists, being an emanation of matter and manifestation of spirit, mediator between the two realms.

Alchemy was the bridge across which the rich symbolism of the ancient world – Arab, Greek, Gnostic – was transported into our own era … thus symbolism fell from the rarefied heights into the melting-pot, and began to be tested in a continuous, dynamic interaction with the findings of chemistry.⁵

The Scientific Revolution

Throughout the Renaissance period, aromatic materials filled the pharmacopoeias which for many centuries remained the main protection against epidemics. Over the next few centuries the medicinal properties and applications of increasing numbers of new essential oils were analysed and recorded by the pharmacists. The list included both well-established aromatics such as cedar, cinnamon, frankincense, juniper, rose, rosemary, lavender and sage, but also essences like artemisia, cajeput, chervil, orange flower, valerian and pine.

The perfumery and distillation industries attracted illustrious names of the day and in the northern countries of Europe, especially at Grassein France, flourishing commercial enterprises sprang up. By the end of the seventeenth century, the profession of perfumery broke away from the allied fields, and a distinction was made between perfumes and the aromatics that had become the domain of the apothecary.

Alchemy gave way to technical chemistry, and with it went the interest in the inter-relatedness of matter and spirit, and the interdependence of medicine and psychology. There developed the idea of combating speculation with logic and deductive reason. With the scientific revolution of the early nineteenth century, chemists were able to identify for the first time the various constituents of the oils, and give them specific names such as ‘geraniol’, ‘citronellol’ and ‘cineol’. In the Yearbook of Pharmacy and Transactions of the British Pharmaceutical Conference in 1907, we find for example:

A pilea of undetermined botanical species has yielded a white essential oil with an odour of turpentine … A small amount of pinene was detected but its other constituents have not yet been identified. This oil is of interest as being the first instance of an essential oil derived from the family Uricaceae.⁶

It is ironic that this enthusiastic research laid the ground for the development of the oils’ synthetic counterparts, and the growth of the modern drug industry. Herbal medicine and aromatic remedies lost their credibility as methods of treatment went out of the hands of the individual and into those of professionals. By the middle of the twentieth century, the role of essential oils had been reduced almost entirely to their employment in perfumes, cosmetics and foodstuffs.

2. AROMATHERAPY AND HERBALISM
The Birth of Aromatherapy

The term ‘aromatherapy’ was first coined in 1928 by Gattefossé, a French chemist working in his family’s perfumier business. He became fascinated with the therapeutic possibilities of the oils after discovering by accident that lavender was able to rapidly heal a severe burn on his hand and help prevent scarring. He also found that many of the essential oils were more effective in their totality than their synthetic substitutes or their isolated active ingredients. As early as 1904 Cuthbert Hall had shown that the antiseptic power of eucalyptus oil in its natural form was stronger than its isolated main active constituent, ‘eucalyptol’ or ‘cineol’.

Another French doctor and scientist, Dr Jean Valnet, used essential oils as part of his programme by which he was able to successfully treat specific medical and psychiatric disorders, the results of which were published in 1964 as Aromatherapie.

The work of Valnet was studied by Madame Marguerite Maury who applied his research to her beauty therapy, in which she aimed to revitalize her clients by creating a ‘strictly personal aromatic complex which she adapted to the subject’s temperament and particular health problems. Hence, going far beyond any simple aesthetic objective, perfumed essences when correctly selected, represent many medicinal agents.’⁷

In some respects, the word ‘aromatherapy’ can be misleading because it suggests that it is a form of healing which works exclusively through our sense of smell, and on the emotions. This is not the case for, apart from its scent, each essential oil has an individual combination of constituents which interacts with the body’s chemistry in a direct manner, which then in turn affects certain organs or systems as a whole. For example, when the oils are used externally in the form of a massage treatment, they are easily absorbed via the skin and transported throughout the body. This can be demonstrated by rubbing a clove of garlic on the soles of the feet; the volatile oil content will be taken into the blood and the odour will appear on the breath a little while later. It is interesting to note that different essential oils are absorbed through the skin at varying rates, for example:

Turpentine: 20 mins

Eucalyptus and thyme: 20–40 mins

Anise, bergamot and lemon: 40–60 mins

Citronella, pine, lavender and geranium: 60–80 mins

Coriander, rue and peppermint: 100–120 mins

It is therefore important to recognize that essential oils have three distinct modes of action with regard to how they inter-relate with the human body: pharmacological, physiological and psychological. The pharmacological effect is concerned with the chemical changes which take place when an essential oil enters the bloodstream and reacts with the hormones and enzymes etc; the physiological mode is concerned with the way in which an essential oil affects the systems of the body, whether they are sedated or stimulated, etc; the psychological effect takes place when an essence is inhaled, and an individual responds to its odour. With relation to the first two points, aromatherapy has a great deal in common with the tradition of medical herbalism or phytotherapy – in other words, it is not simply the aroma which is important but also the chemical interaction between the oils and the body, and the physical changes which are brought about.

Herbal Medicine

The practice of aromatherapy could be seen as part of the larger field of herbal medicine, since the essential oil is only one of many ways in which a plant can be prepared as a remedy. Since all essential oils are derived directly from plants, it can be valuable to see them within a botanical context rather than as isolated products. In some ways the use of aromatic oils for therapeutic purposes benefits from being placed within a herbal context not only because it gives us further insight into their characteristics, but because the two forms of therapy are not synonymous, but complementary.

Growing and storing herbs: the woman is scenting the linen chest; from Das Kerfiterbuch oder Herbarius, 1534

Although most plants which yield essential oils are also used in medical herbalism, it is important to distinguish the therapeutic qualities of a particular oil from those of the herb taken as a whole or prepared in another manner. German chamomile, for example, is used extensively in the form of a herbal preparation such as an infusion, tincture or decoction, apart from being utilized for its volatile oil. Chamazulene, a major constituent of the oil, helps to account for the herb’s age-old reputation as a general relaxant and soothing skin care remedy, due to its pain-relieving, antispasmodic, wound-healing and anti-inflammatory activities. For the treatment of nervous conditions, insomnia and dermal irritation or disease, the essential oil is both useful and effective. But although the aromatic principle of the plant plays a central role in its overall character, the herb also contains a bitter component (anthemic acid), tannins (tannic acid), mucilage and a glycoside among other things. The overall effect of the herb is the result of the action of all its pharmacologically active constituents which in the case of chamomile or Matricaria includes the astringency of the tannins and the stimulation of the bitters. The volatile oil is, of course, less concentrated in the form of an infusion, tincture or decoction, the potency of the oil is reduced (and inherently the safety margin increased), thus making the herbal preparation more suited to internal use.

Similarly with peppermint. Whilst the oil is eminently suited to the treatment of respiratory conditions as an inhalant, due in particular to its antispasmodic and antiseptic actions, for the longer-term treatment of digestive disorders it is better to use extracts from the whole herb, where the action of the volatile oil is supported by the presence of bitters and tannins. In addition, in herbal medicine, the effect of one herb is usually supported and backed up by combining it with others.

Neither is it correct to assume that the essential oil is always the most active or therapeutically useful part of a plant. For example, although meadowsweet contains an essential oil outstanding in its antiseptic strength (according to Cavel,⁸ 3.3cc of meadowsweet essence renders infertile 1000cc of microbic cultures in sewage, compared to 5.6cc of phenol per 1000cc), it also possesses several other valuable components, notably salicylic glycosides which are characterized by their excellent pain-relieving and anti-inflammatory qualities. Indeed, the familiar drug aspirin, being derived from salicylic acid, is named after this herb, its old country name being ‘spiraea’.

The kernels of the (bitter and sweet) almond tree are used to produce a fixed oil commonly known as sweet almond oil, which has a great many cosmetic uses. The kernels from the bitter almond tree, which are used to produce the essential oil which gives marzipan its characteristic taste, also contain cyanide, the well-known poison, in its unrefined form. This shows that there can be a great difference in the properties of a plant, even the same part of a plant, depending upon how it has been prepared.