So sometimes you wonder if you are getting the purest form of essential oils. I have posted the article straight from the doTERRA page to show you how doTERRA does their quality testing.
CPTG Quality Testing
The purity of an essential oil is its most important characteristic. An essential oil that isn’t pure means you run the risk of putting germs, heavy metals, or adulterants onto or into your body, which can provoke irritation, adverse effects, or even sickness. Without an accepted standard for essential oil quality, doTERRA created its own testing process, calling it CPTG Certified Pure Therapeutic Grade®. The CPTG process certifies that there are no added fillers, synthetic ingredients, or harmful contaminants in their essential oils that would reduce their efficacy. doTERRA even goes a step further, putting all their products and the packaging through a battery of tests to ensure a long and effective shelf-life. This protocol ensures potency, purity, and consistency batch to batch.
https://www.doterra.com/US/en/cptg-testing-process
Oils and Essentially You 