We all know how important it is to check expiration dates on food, but many of us are guilty of keeping personal care items that have gone past their use-by date.
Some of these, like topical products, are harder to tell if they have expired. Essential oils are a good example.
These oils have antibacterial properties and don’t contain water, so they won’t form mildew, yeast, or mold as they age. This may make you wonder, do essential oils expire?
Simply put, the answer is yes. They may not go moldy, but this doesn’t mean that they won’t spoil. Essential oils can go bad, and using them can lead to undesirable effects.
You’ll learn more about the lifespan of essential oils in this post, including what elements make them go bad, how to tell if the oil has spoiled, and how to store your essential oils to maximize their life span.
What Makes Essential Oils Spoil?
Pure essential oils aren’t affected by mildew, mold, or yeast, which turns other products rancid. If a pure essential oil bottle is sealed and kept in a cool, dark place, it can have a very long lifespan.
Issues begin to form when the oils are unprotected against external factors. These can affect the safety, fragrance, and therapeutic characteristics of the oils.
The benefits and aromatherapy properties of essential oils depend on the active substances within them.
The most significant examples are sesquiterpenes, monoterpenols, monoterpenes, monoterpenoids, and sesquiterpenoids. The last two ingredients can oxidize if they come in contact with the air.
In the same way that oxygen takes electrons from iron and makes it rust, oxygen takes electrons from these important ingredients inside essential oils. As a result, their chemical structure changes, so they become less beneficial.
This change won’t turn the oils rancid, but they won’t have the same benefits you initially purchased them for.
High Temperatures And Light
Sunlight can rapidly transform the chemical structure of essential oils (see also “How To Make The Ultimate Sugar Scrub With Essential Oils“). This occurs because after a brief period of contact with UV light creates oxygen-free radicals in the essential oils.
This changes their chemical composition, and may even create new ones.
For instance, a 2005 study found that oxidation made the components of sweet fennel oil change fully when kept in contact with light for two months.
A different study looking at sweet orange essential oil discovered that the oil experienced drastic changes after 50 minutes of UV light exposure.
More studies are needed to look into the effects of heat on essential oils, but manufacturers usually advise keeping the oils away from both sunlight and heat.
Signs Essential Oils Have Spoiled
It can be hard to tell if an essential oil has gone bad. A few examples, especially citrus oils that contain limonene, have a foul odor. However, other oils don’t always exhibit the same signs.
Fortunately, there are different ways to tell whether oxidation has affected your essential oils. Some change color, like chamomile and peppermint, while others have a distinct change in consistency.
If your essential oils have spoiled, they will not be suitable for topical use (after dilution) or diffuser use. They will have lost any of the therapeutic properties you bought the oils for.
Some essential oils, like lavender or tea tree, should never be used after they have oxidized. These can lead to skin sensitivities or negatively affect mucous membranes.
The Lifespan Of Essential Oils
All essential oils will have a different lifespan, as their chemical structure differs between each type.
In most cases, your essential oil will last a minimum of two years before it begins to break down, unless they are mixed with an unstable carrier oil.
To be on the safe side, It’s advised to replace essential oils after three years. The only exceptions are vetiver, patchouli, sandalwood, and ylang-ylang. These oils get better as they get older.
Storing Essential Oils
You can maximize the life of your essential oils by storing them correctly.
When you first buy your essential oil, make sure that it is packaged in a dark-colored glass bottle.
This will prevent UV rays from affecting the product inside the container. Most essential oils are kept in an amber-colored glass bottle which diverts sunlight.
Essential oils can break down plastic bottles, so they should always be kept in glass containers.
Amber glass bottles do divert UV light, but you should always keep the bottles out of the sun. Heat and sunlight can accelerate oxidation, but you can prevent this from occurring by keeping your oil bottles in a cool, dark, and dry location.
It’s also a good idea to keep essential oils in smaller containers. Smaller bottles stop oxygen from being trapped in the container after it has opened. This will stop oxidation from occurring too early, optimizing your essential oils’ lifespan.
Essential oil bottles should always be fastened securely and stored properly, as this prevents chemical evaporation and oxidation. Stick to essential oil safety advice, such as keeping them away from flames, high temperatures, pets, and children (see also “DiGize Essential Oil Blend: How To Use, Safety & FAQs“).
Some essential oils can be refrigerated, as this prevents heat-related oxidation. A few oils, like rose otto, aniseed, and fennel, can become solid in the cold, but the temperatures won’t damage the product.
If you do store your oils in the fridge, take them out of the fridge 12 hours before you need to use them. If you notice any waxy pieces in the oil, shake the bottle and see if this helps.
Is It Bad To Use Expired Essential Oil?
If your essential oil has spoiled, you may be questioning if there are any risks related to using them.
If an essential oil has oxidized, its chemical structure changes. This doesn’t just affect the way it smells.
Essential oils that have gone bad can lead to rashes, irritation, burns, and other detrimental symptoms. For example, lavender oil and tea tree oil often irritate after they have oxidized.
To avoid any adverse effects, never use expired essential oils on your skin or inhale them after they have spoiled.
How To Dispose Expired Essential Oils
If you think your essential oils have spoiled, you may question if they can be poured down the sink to get rid of them.
You should never throw essential oils down your drain. The oils can affect your pipes, and in more serious cases, may seep into the water supply and affect the environment.
There are better methods of disposing of expired oils which are eco-friendly and don’t block your pipes. Here are some ways to dispose of expired essential oils:
- Check with your city, state, or county’s rules on disposing of oils. Regulations change between different locations, so it’s a good idea to look up your location’s proceedings.
- If a waste management company handles your trash, ask them about the best way of disposing of your oils. They will probably have a better technique for disposing of chemical products.
The Bottom Line
Like a lot of things, essential oils do expire!
Most essential oils need to be replaced after every two to three years. If you suspect that your product has spoiled, do not use it, as it may cause irritation, burns, or other adverse symptoms.
Even though essential oils have a shelf life, you can maximize their lifespan by storing them correctly.
Keeping your oils away from sunlight, heat, and moisture will ensure that you can enjoy using them for a long time.