Nature Identical essential oils are blends of essential oils, various extracted aromatic compounds, and constituents of essential oils or synthetic chemicals. They may be a rectified blend of components that mimic the chemical structure of the original oil. They are to pure essential oils what nutritional supplements are to whole foods, somewhat comparable to getting your nutritional needs met through supplements rather than food.
The synthetic constituents used mimic the chemical spectrometry of natural consitutents from the plant. They smell like their natural equivalents but contain on average noticeably fewer complete constituents found in the oil they copy, and may have unknown chemical additives. Synthetic oils do not have a direct counterpart in nature in terms of ingredients but are chemically copied and mixed. Often they are called ‘scented oils’ or ‘scent oils’ and are typically less expensive.
Nature Identical essential oils are generally used in industry for fragrance purposes as they are less expensive and tend to be more fragrant than essential oils in their pure form. Using nature identical oils can solve a common problem for product formulators who don’t want to use completely synthetic fragrances. They can help product formulators achieve that intense fragrance but in a way that is somewhat safer, much cheaper, and can technically be considered somewhat natural.
However, they are not considered appropriate for food use (they are used to flavor teas and other foods in some Middle Eastern Countries) or any kind of clinical aromatherapy. Conventional wisdom says that if your goal is to create something of therapeutic value then you should never use anything but pure essential oils. Having certification on the oils you purchase for aromatherapy will include a lot-specific GCMS (Gas Chromatography Mass Spectrometry) analysis from reputable purveyors, especially important if buying through a retailer or multi-level marketing representative (who usually cannot provide this important technical information that so necessary for clinical applications).
Why is this important? Because disreputable bulk sellers are usually from countries that do not meet the same health and safety standards as in Europe or North America, and have been known to adulterate lots of ‘pure’ essential oils with synthetic constituents. These fraudulent lots are sold only after initial test samples of pure high-quality oils representing those lots have been provided and passed mass spectrometer testing by the purchaser, and have been approved for purchase. Then the incoming shipment of oils may be of much inferior quality not at all matching the original approved samples.
Aromatherapists have unwittingly used such products on their patients, so be sure to make your purchases through reputable sources only.