The good news about essential oils is they are often bactericidal, fungicidal and virucidal in their own right, meaning they do not support the growth of most organisms, even when they are inadvertently inoculated (69). This offers nurses and other health professionals added reassurance regarding EO safety with post discharge use.
The essential oil distillation process removes the majority of impurities such as pesticides and synthetic chemicals, though trace amounts can remain. Essential oil products have no formal industry classification or grading system, but can be identified based on levels of purity and quality, which are a direct effect of the distillation process. Many less “pure” EOs are used in the food industry as flavoring, with more refined EOs being used in the perfume industry. The quality of therapeutic EOs is enhanced by careful distillation that is specific to the EO being extracted.
Unexpected substances can be found in commercial essential oil products. These include adulterants such as other essential oils or constituents of essential oils, such as linalool, that are added to make the products emit a distinctive smell. Extenders such as cottonseed oil, or even synthetic chemicals, have been found in EOs to add volume in order to obtain a higher price. An extreme example of adulteration is when individual synthetic constituents are combined in an attempt to mimic a pure essential oil, such as mixing synthetic linalool and linalyl acetate to masquerade as pure Lavender EO.
To circumvent these issues, it is advisable to purchase from companies that provide gas chromatography and mass spectroscopy reports with their essential oils, which should reveal the true content of the product. Companies should also be able to produce a Safety Data Sheet for each oil or specific oil blend, and this should be a requirement for use in a patient care setting.
Another important consideration is that there is currently no certifying body that bestows a “therapeutic grade” designation. If these words are found on packaging, it can be regarded as a manufacturer’s marketing tool, either to reassure buyers that their product is pure and safe, or to convince the buyer that it is. This is truly a “buyer beware” situation. Purchasing from an established company that has a known reputation for quality is the first step to obtaining a good product.
Reputable, high quality essential oil manufacturers focus on plants that are cultivated organically or grow in their natural habitat. They use the best manufacturing practices available to distill or press their essential oils. They bottle the EOs in containers that prevent oxidation and degradation, and they store and transport them at the correct temperature, out of direct sunlight.
Variations in the aroma of individual essential oils or blends are to be expected. Just as a particular wine tastes slightly different from year to year, the same conditions apply to EOs. Rainfall, hours of sunlight and time of harvest will ultimately affect the final odor constituents of an EO. In a perfume, the composition can be manipulated synthetically to provide a consistent signature smell, but with high quality essential oils, nothing is added or altered. This ensures that the inherent chemical composition of the plant is preserved intact in order to be of genuine therapeutic quality.
Another important point to consider is that manufacturers producing essential oils of this level of quality, most likely won’t be able to offer the lowest prices. Although these uncompromising production practices cost more, they will produce essential oils that provide the safest and best therapeutic results.