Essential Oil Testing and Standards

Testing essential oils for purity, whether the plants are grown and distilled by the seller or the final product is purchased from a third party, is not required to label the product as therapeutic-grade. In the United States, the labeling of essential oils as therapeutic is entirely up to the manufacturer as there are no regulations. Any oil, whether adulterated or not, can say on the label that the oils are 100% pure and therapeutic. A good way to be certain you are purchasing a therapeutic-grade essential oil is to know your seller and purchase AFNOR or ISO certified products.

In Europe there are standards regarding therapeutic-grade essential oils and there are two organizations that have created the necessary standards. These organizations are AFNOR (Association of French Normalization Organization Regulation) and ISO (International Standards Organization).

In order for essential oils to meet these standards, testing must show that certain primary constituents are present in certain percentages. This testing is done using a method called gas chromatography; a complex system requiring chemists specially trained in interpretation of the gas chromatography charts. Proper equipment, including at least a 50-meter testing column, must be used.

The lab must also be AFNO/ISO certified and be independent from the seller of the finished product.

An expample of test results from a gas chromatograph chemistry profile is below. This result would be analyzed to see if certain markers are met. If the markers are good, then the results of the analysis will show that the sample is pure and free from common adulterants.