As the demand for essential oils increases, new terms have been introduced to describe the oil’s purported quality as a way of remaining competitive in the marketplace. Of these terms, ‘Therapeutic Grade Essential Oil’ is commonly displayed on labels and in advertising. It’s important to note that with no standard definition, or pre-market approval by the FDA, the term ‘Therapeutic Grade’ is simply a marketing term, and does not indicate an oil’s quality or purity.

Gas chromatography-mass spectrometry (GC/MS) is one of the most popular and standardized methods of testing essential oils. This form of testing allows scientific researchers, suppliers, manufacturers and businesses to determine the essential oil purity and quality. Results are often compared against a reliable sample to determine optimal quality, or changes from batch to batch.