Essential oils are part of a very pleasant and most of the times, effective therapy. It’s called Aromatherapy. Using them is often a nice, fragrant experience. But how long do essential oils last? Do they have a shelf life, and if so, what is it? These things are important to know so you can use your oils safely, for a longer time.
In this article, I’m going to tell you more about:
- The chemistry of essential oils. It may sound hard to understand or pointless. But the truth is you need this info to understand the shelf life of oils.
- Frequently asked questions about aroma oils and their expiry date.
- A list of therapeutic oils and their shelf life to use for future reference.
- Tips to increase the shelf life of your essential oils. This will prove economical and beneficial, and you’ll see why along the article.
Understanding Aromatic Oils (A bit of Chemistry and FAQ)
Essential oils are easy to use and find (most of the time). They are also a great alternative to medicines, especially when you’re dealing with mild affections.
They’re capable of improving the aspect of the skin. They can also boost hair growth and soothe digestions, respiratory problems, etc.
But haven’t you ever wondered how they do that? Well, it all starts with their making and chemical profile.
Essential oils are not exactly oils. True oils are known as carriers or vegetable oils (Olive, Jojoba, etc.). Carriers are mechanically pressed from nuts, seeds and/or kernels. Carriers are also fatty because they contain fatty acids.
Essential oils however, are concentrated plant extracts. They’re extracted by steam distillation from leaves, twigs, bark and roots. Resin and sometimes seeds are used for steam distillation too.
Plants store oils in specific chambers/glands and use them for protection. This protection can be against the sun, wind and cold or from predators. The latter is done by emitting certain scents to keep animals at a safe distance.
These oils are collected with the help of steam. The oils are made of tiny, volatile molecules that are heavier than water molecules. That is why they float and emit scents.
So the oil molecules are heavier than water and they’re the essence of plants. Because of these things, they are called essential oils.
Essential oils don’t leave a greasy film on the skin. On the contrary, the most part of an oil gets absorbed into the skin very fast. Another part of that amount simply evaporates into the air. Skin absorption is made through the pores and hair follicles.
Regardless of what you’ve heard before, essential oils do expire. They are very active substances that can go bad after opening. We will soon see what causes essential oils to go bad.
Knowing the chemical composition of an essential oil can help you figure out its shelf life. Sure, it’s easier to just have it written somewhere. But you could also use this bit of info when you stumble upon a more exotic or new essential oil.
Generally speaking, a plant essence contains tens, sometimes even hundreds of different molecules. Each molecule belongs to a class with its own characteristics and effects on our health.
Next, you’ll see some major constituent classes and their shelf life. They give the oil its properties and benefits.
Chemical constituents and their shelf life:
- Alcohols (menthol, bisabolol) – 1 – 3 years shelf life
- Aldehydes (citral, geraniol) – 4 – 5 years shelf life
- Ketones (thujone, camphor) – 4 – 7 years shelf life
- Esthers (methyl salicylate, bornil acetate, linalyl acetate) – 4 – 5 years shelf life
- Ethers (1,8 cineole) – 5 – 7 years shelf life
- Hydrocarbons (limonene, Alpha and Beta pinene) – 9 months – 2 years shelf life
- Phenols (carvacrol, thymol, eugenol) – 3 – 6 years shelf life.
- Sesquiterpenes (zingiberene, humulene, caryoplyllene, patchoulol) – 6 – 10 years shelf life.
The chemical composition of en essential oil may vary because of several reasons. It depends on the geographical area where the plant grew, the harvest time and processing.
You can see the chemical profile of an oil in its GC/MS report. It is the lab analysis that shows whether the oil is pure or not and its constituents. You can ask your seller for this report, for free.
FAQ about Essential Oils and Their Shelf Life
Here are a few questions you might ask yourself about the oils you use. If you have more questions, don’t hesitate to use the comments section. I’ll make sure you get all your facts straight.
a) How long do essential oils last?
How long do essential oils last once open? As you’ve seen, it really depends on the oil you’re using.
Some have a higher antibacterial and antioxidant effect which generally helps. However, if you’re not storing them properly, they can go bad a lot faster.
Let’s take Oregano as an example. Does the oil of Oregano expire too, you might wonder. Yes, Oregano can also expire. Its main constituent is carvacrol, a highly antifungal and antibacterial molecule.
Its shelf life can be anywhere between 3 to 6 years. The better you store it, the longer it’ll preserve its therapeutic effects. Of course, this applies to all plant extracts.
Essential oils usually have an expiration date on their label. But, if they’ve been kept in dark, cool places, their shelf life should not be changed too much. This means that only after you open the bottle of essential oil, it will start oxidizing.
It also means that the oil’s shelf life can be longer than the one written on the label. Unfortunately, we can’t know the details of their shipping and storage though.
b) What makes essential oils go bad?
Aromatic oils can become bad because of three factors: oxygen, heat and light. Volatile oils are very complex and active. When oxygen, heat or light get in contact with the oil molecules, they start the spoiling process.
We say that carrier oils go rancid while essential oils oxidize. They oxidize because the oxygen reacts with them. If you apply oxidized oils on your skin, they can damage the tissue.
Antioxidants for instance, repair the damage caused by sunlight and air (oxidation). Oxygen is a corroding agent. Even though we need it to survive, oxygen also contributes to the aging process.
Heat and light also change the composition of volatile oils. Heat causes evaporation and light is the cause of free radicals. The shelf life of essential oils starts to change after being bottled.
The way they’re stored and shipped can decrease their shelf life. Or, they can at best, maintain it as it was.
Other factors that can shorten the life of essential oils are:
- If you don’t keep them tightly closed.
- If you let water inside the bottle of the essence.
- Also, if you touch the dropper, you can contaminate the oils.
c) What happens if you use old or oxidized essential oils?
This question should be everyone’s concern. Why? Because, when essential oils go bad, they lose their properties. Thus, they also lose their beneficial effects on our health.
In other words, you’d use them for no purpose. On top of that, they can also irritate or sensitize the skin and mucus membranes.
They should also not be used in diffusions/inhalations. The reason is the same as for skin applications. There is no point in using an essence once it has lost its powers.
Some people suggest using expired essential oils as cleaning agents. But again, that won’t do much good. You need them still active to disinfect and kill bacteria.
d) How do you know whether your essential oils have gone bad or not?
There are big chances for your newly purchased essential oils to be good. If it’s close to its expiry date, the oil will change:
- Fragrance – It should smell less pungent and even bad, in some cases. You’ll know this because you’ll remember how it first smelled like.
- Viscosity – A bad essential oil will start thickening. It may also appear sticky.
- Aspect – There can be sediments and the oil might look cloudy when it’s spoiled. This can be seen mostly in blends, when you use clear, transparent bottles.
Generally speaking, once open, essential oils last at least 6 months. Lemon essential oil and some conifer oils like Pine are very sensitive to oxidation.
The rest of essential oils have a longer shelf life and this is usually a good thing. However, if you like Aromatherapy, you’ll go through oils long before they get to go bad.
Knowing how long essential oils last can help you a lot when you’ve got a large inventory. Or when you’ve not used aromatic oils in a very long time.
Shelf Life of Essential Oils (List) and Tips
The majority of essential oil molecules can be synthesized in a lab. With them, it’s easy to determine an expiry date. But when we’re dealing with pure essential oils, they are highly complex and active.
They also act in a complete synergy, which makes it even harder to determine an accurate expiry date.
I’ve made a list of essential oils and their shelf life. I’ve categorized them according to their resistance in time, starting with the lowest shelf life. The list is non-exhaustive though, and can be completed with your own information too.
Shelf Life: 6 months/1 year – 2 years
- Citrus Essential Oils
- Pine essential oil
- Spruce essential oil
- Cypress essential oil
- Angelica essential oil
- Frankincense essential oil
- Lemongrass essential oil
- Tea Tree essential oil
The higher they are in limonene and/or pinene, etc., the shorter their shelf life is. That explains the big difference of shelf life between them.
Shelf Life: 2 – 3 years
- Blue Tansy
Shelf Life: 4 – 6 years
- Rose Geranium
- Lavender Ginger
- Clary Sage
Shelf Life: 7+ years
Just remember that these are approximations. The shelf life of essential oils may drastically change once you open the bottle.
It all depends on you. But this brings us to the next section of the article. You’ll find some really interesting and helpful tips to help you increase your essential oils shelf life.
Tips to Increase the Shelf Life of Essential Oils
Do essential oils expire? Now you know they do and that it’s up to you to keep them in the best conditions possible. These tips can help you save some money as well.
- Keep all your essences away from direct sunlight.
- Keep them away from heat sources also.
- After opening, citrus oils and coniferous oils (pine, fir, etc.) should be kept in the fridge.
- Blends of pure essential oils should be kept in dark glass bottles (amber is the best). Aromatic oils can slowly dissolve the plastic.
- Close them tight right after use to avoid evaporation.
- Avoid touching their droppers with your skin or water.
- Don’t refill an already used bottle. The oxygen inside it will oxidize the oil faster.
- Essential oils are also called “hazardous”. Check with your local waste management department to find out how to dispose of large quantities. Really small quantities can simply be thrown out.
- Buy small bottles (10 ml or less) to make sure you’ll be using all the oil. You might discover you don’t like the smell so much and a larger bottle would simply be a waste.
- Buy your oils from trusted sources.
- Buy sticker labels and write down the date you opened the bottle. That’ll help you keep track of their shelf life better.
As you can see, it’s not hard to make the best of your essences. Knowing that essential oils can go bad and that some of them are quite expensive is reason enough to store them properly.
Don’t forget to always test for allergies every new oil bottle you buy. Their chemical composition is relatively different almost all the time. Thereby, there is always the risk of a skin reaction.
Pregnant and nursing women should use them only with the doctor’s approval. Children and elderly people should not use the oils without medical guidance. The same goes for people with chronic illnesses. Internal use of oils is not recommended without the advice of a doctor!
Do essential oils go bad? How long do essential oils last? What happens if you use oxidized oils? All these are good questions that everyone who likes using essential oils should know the answer to.
It’s easy to store them in cool, dark places. This good habit will ultimately lead to a more comfortable day-to-day life. Pure, not oxidized oils have many therapeutic effects on the mind and body. They will help you relax, unwind, sleep, digest, etc.
Have you ever had a bad experience with oxidized essential oils? I would very much like to hear your thoughts on this matter.