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Essential oil

(Redirected from Ethereal oil)

An essential oil, also known as volatile oil and ethereal oil, is a water-immiscible liquid produced by distillation from plant material that is used in perfumes, cosmetics, incenses, and in medicine.

Contents

Production

The raw material (flowers, leaves, stems, or roots, seeds, or seed peel, depending on the plant) is put in an alembic over water, and the volatile compounds, which require less vapor pressure to evaporate with the presence of steam, distill into a receiving vessel. The upper portion is the oil, the lower being the hydrosol. Most oils are distilled in a single process. The exception is ylang-ylang, which takes 22 hours to complete distillation. It is fractionally distilled, producing several grades.

Many vendors sell fragrance oils which are blended synthetic aroma compounds or essential oils diluted with a carrier like propylene glycol, vegetable oil, or mineral oil.

Medicinal uses

Many essential oils have medicinal properties that have been applied in folk medicine since ancient times and are still widely used today. For example:

Aromatherapy is a form of alternative medicine, in which healing effects are ascribed to the smell of particular fragrances.

Prior to the discovery of distillation essential oils were extracted by pressing, and this is still the case in cultures such as Egypt. Traditional Egyption practice involves pressing the flower and then burying it in unglazed ceramic vessels in the desert for a period of months to drive out water. The Lotus oil retaining its scent after 3000 years in alabaster vessels in Tutankhamun's tomb was pressed, rather than distilled.

Dangers

The smoke from burning essential oils may contain dangerous cancer producing products, such as polycyclic aromatic hydrocarbons (PAHs). The essential oils themselves are volatile organic compounds (VOCs).

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07-14-2008 23:18:10
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