Most people are quite surprised to find out that essential oils have a shelf life. Some may have even been told otherwise simply to justify a higher price tag.
However, the truth is that essential oils have a shelf life no matter what brand you purchase from. This is due to the fact that essential oils are volatile and have the potential to oxidize. In chemical terms, a volatile substance, such as essential oils, can evaporate. If they didn’t, you wouldn’t be able to smell them in the first place.
How volatile an essential oil is will depend on its constituents. Those with lighter constituents are the most volatile and are likely to be the first to evaporate. Heavier constituents however, will be the last ones to go.
Estimated Shelf Life of a Few Popular Essential Oils
1 Year: Grapefruit, Lemon, Orange
2 Years: Frankincense, Tea Tree
3 Years: Oregano, Rosemary
6+ Years: Cedarwood, Ginger, Patchouli, Sandalwood
What Makes An Essential Oil Go Bad?
Essential Oil Safety states that contaminants and degradation can all increase the toxicity of essential oils and can cause them to spoil. When it comes to degradation of essential oil, it typically occurs from three ways: heat, light, and oxygen.
Heat: As you can imagine, heat can cause the more volatile constituents of essential oils to evaporate or even transmute more quickly. If you do not have any children to worry about, you might want to keep your oils in the refrigerator to ensure it doesn’t get damaged by changes in temperature.
Light: Ultraviolet light can also damage your essential oil by promoting free radicals. Thankfully, amber colored bottles are great at keeping UV light from harming their quality. Still, you may want to ensure that your essential oils are always stored in darkness to stay on the safe side.
Oxygen: When oxygen gets into your essential oil bottle, it can cause a reaction with the constituents of the oil. This is known as oxidation and is perhaps the most common and rapid form of degradation of essential oils. This can cause the therapeutic properties of the essential oil to breakdown, change their chemical composition and increase your risk of sensitization. This is why you must always make sure your essential oils are sealed tightly and only exposed to air for short periods of time. In addition, only use essential oils in moderation.