How to Know if an Essential Oil is Pure: All About GC/MS Testing

4 min to read
Karen Williams
How to know if your essential oils are pure?

Here is a reliable way to know if an essential oil is pure (and why you should care).

Back when I first began sourcing essential oils, I had a wake-up call.

I had heard that adulteration (the practice of adding substances to bottles of essential oil) was unfortunately common in the Aromatherapy industry. And that it isn't always easy to know if an essential oil is pure.

But I used essential oils from a company that I knew and trusted. I wasn't worried about adulteration.

I always tested each batch of oil I received and sent off a sample of Frankincense essential oil tested by a Chemist. I wasn't concerned about whether the essential oil was pure (I was sure it was). I just wanted to know what the components of the oil were, which made it so wonderful.

So I sent the Frankincense essential oil to a lab to have it tested with GC/MS technology.

GC/MS stands for "Gas Chromatography/Mass Spectrometry."

I know . . . that sounds very sciencey, haha!

Don't worry—all you need to know is that GC/MS tests tell us the components that are present in essential oil. The test breaks it all down like a list of "ingredients."

I wanted to know what the "ingredients" of my Frankincense essential oil were.

Imagine my surprise when the lab report came back and said that my "Frankincense essential oil" was actually only 2% Frankincense essential oil! The rest was all synthetic! The essential oil was not pure!

I'll bet you can imagine, I was so shocked.

I would NEVER have guessed that the essential oil was synthetic!

And I was concerned . . .

Not only are synthetics not therapeutic (they do not offer the natural, health-supporting benefits of pure essential oils), but they can actually cause sensitivities, irritations, and other reactions for some people.

That's when I realized how important GC/MS testing is. We have to know if an essential oil is pure, especially if we're going to use it therapeutically.

GC/MS testing is not really feasible for individuals because a single test usually costs several hundred dollars. It's not realistic for most people to have their entire essential oil collection tested! But for essential oil suppliers and Aromatherapy companies who purchase directly from distillers, one test can be done for the entire batch of essential oil they purchase.

From there, it is a very simple step to provide a copy of the lab report to their customers.

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In addition to helping you know, if an essential oil is pure, a GC/MS report can show you . . .

  • What therapeutic benefits an oil might offer, based on its natural components

  • Any safety issues to be aware of (again, based on the natural components)

Why would you want to look at a GC/MS report for an essential oil that you know and love?

Because an essential oil's natural components can be affected by things like the country the plant was grown in, the weather conditions in the region, how much water and sunlight it received, the temperature, and even when the plant was harvested!

Based on all of these factors, the essential oil that the plant produces can have variations in its natural chemistry.

The GC/MS report shows you exactly what components are present in your essential oil—and this is so helpful if you're using essential oils therapeutically for yourself, for friends, or for clients.

A good example of this is Helichrysum essential oil.

Helichrysum from Corsica tends to have more components in the ester chemical family, which make it great for calming.

Helichrysum from Croatia tends to have components in the sesquiterpene chemical family. This makes it amazing for skin care and healing.

How do you know for sure which variation of Helichrysum is in your bottle?

A GC/MS report is the best way to know for sure!

The more you understand essential oil chemistry, the more useful you will find a GC/MS report.

But even if you know nothing about chemistry, a GC/MS report can help you know if an essential oil is pure and not adulterated.

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About the author

Karen Williams - Aromahead Institute

Karen Williams

R.N. Certified Aromatherapist, Educator

I love to create amazing blends that inspire and promote a healthier lifestyle. I got my start many years ago as a registered nurse working in the hospital system. I wanted to help people more holistically. Then, I discovered essential oils, and my approach to life changed forever. Now, I’ve made it my mission to share what I’ve learned about aromatherapy with my friends, family, and the world. Because - life is so much better with health, happiness, and community.

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