What is an essential oil?


The benefits of essential oils and how they differ from fragrance oils

Cosmetics Business is asking personal care industry experts to answer the cosmetics world’s big questions. Here experts discuss essential oils, their benefits and how they differ from fragrance oils.

Over to the experts...

Margaret Pawlaczykkarlinski

Margaret Pawlaczykkarlinski

Margaret Pawlaczykkarlinski, on behalf of the International Federation of Aromatherapists

Essential oils are aromatic, volatile substances extracted from a single botanical source, by distillation or expression (citrus fruit peel only).

When these methods cannot be used successfully, eg jasmine flowers, solvent extraction is used resulting in 'absolutes'.

Essential oils have a very complex chemical composition, which may vary from batch to batch, depending on the growing conditions.

An essential oil may comprise hundreds of different chemical compounds, all of which contribute to the aroma and specific therapeutic properties.

Essential oils are used synergistically in aromatherapy practice where their distinctive therapeutic properties may help various health conditions, from skin problems, muscular and arthritic pains to menstrual, respiratory and stress related issues.

Research and clinical studies from around the world show the positive effects of aromatherapy, for example, the efficacy of some essential oils against MRSA (geranium and tea tree) or significant improvement in cognitive function in patients with Alzheimer's disease (lemon and rosemary).

Some essential oils may present safety challenges such as skin and mucous membrane irritation or phototoxicity.

Some interact with drugs (eg anticoagulants) or might not be suitable for those suffering from epilepsy or pregnant/breastfeeding women or babies.

The International Federation of Aromatherapists (IFA) regulates and accredits standards in aromatherapy for both the practitioners and the course providers.

Essential oils are used in cosmetics, usually 'just' as a fragrance or masking agents. We might not be able to make claims as to their therapeutic value but a good selection can certainly support and 'work with' the product.

Sixteen out of 26 allergens currently listed by the EU Cosmetic Legislation can be found in essential oils and it is mandatory to declare these allergens on product labels.

Essential oils are often confused with fragrance oils, which are synthetically made, standardised products not suitable for aromatherapy practice.

The ‘essential’ part of the name comes from ‘quintessential’, reflecting the ancient belief that the fragrant compounds were the ‘essence’ or vital spirit of the plant

Anne Murray

Anne Murray

Anne Murray, Aromatherapy Expert, Aromatherapy Associates

Essential oils are highly fragrant, volatile plant extracts sourced from a wide range of plant materials, such as flowers, leaves, roots, wood, resins, buds and berries.

Aromatic plant extracts have been used as therapeutic agents for thousands of years; today, they are ever more popular – most people are aware that lavender oil is a relaxant and tea tree is highly antiseptic.

Excitingly, modern research is confirming many of their traditional benefits and uses.

The 'essential' part of the name comes from 'quintessential', reflecting the ancient belief that the fragrant compounds produced during the plant's metabolism were the 'essence' or vital spirit of the plant; 'oil' denotes they are lipophilic, combining more readily with oil than water.

In fact, most essential oils appear thin and watery rather than obviously oily. Although the term 'essential oil' is often used to describe any fragrant plant extract, strictly speaking it should be reserved for aromatic oils that are obtained by the process of distillation.

In this method of extraction, the plant material is placed into a large tank. Steam is piped through, and the heat dissolves the walls of the plant cells that hold the aromatic chemicals.

This now-fragrant steam is directed into a second vessel – the condenser – where it can be cooled quickly before being collected.

The liquid settles, with the oil usually rising to the top leaving a hydrosol (floral water) below. This aromatic oil can now be called an essential oil.

Once extracted, essential oils should be stored in light-proof containers at a cool temperature. Most will last unopened for several years, with citrus extracts having the shortest shelf life.

In aromatherapy, essential oils are diluted by blending them with vegetable carrier oils or into other suitable formulations before being used for massage, skin care or as bath and shower oils.

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They can also be used for room fragrancing, or incorporated into body washes, shampoos, soaps, candles and other cosmetics.