Part 4: Quality Testing—GCMS

No matter how carefully the distillation process is carried out, essential oils should be tested for their purity and potency before being packaged. Quality testing ensures that every bottle of essential oil contains nothing but 100 percent pure volatile aromatic compounds at the correct ratios to allow for maximum efficacy. Together, gas chromatography, mass spectrometry, infrared spectroscopy, heavy metal testing, organoleptic testing, and microbial testing provide a canon of quality testing procedures that allow for the most thorough analysis possible. Additional tests such as isotopic analysis and chirality testing also provide important information about the quality of essential oils.

There are two main goals of these quality control tests.

1. Verify Potency: To identify the chemical composition of the product, which in turn determines the oil’s potency and other properties.
2. Ensure Purity: To determine if the oil is pure, or free from contamination and adulteration. An adulteration is the addition of any natural or synthetic component (cheaper essential oil, vegetable oil, mineral oil, essential oil component, etc.) that would cheapen the price of the oil. Not only do adulterations have the potential to alter the chemical and physical properties of the oil, but they can decrease the efficacy of the oil and even cause adverse effects.

Unfortunately, there is no regulatory body that oversees the quality or safety of essential oils. It is therefore up to us to ensure that our products are completely pure, free of adulteration, and have the desired beneficial characteristics.