When Essential Oils Expire

Have you ever seen an expiration date on a bottle of essential oils? Probably not since it's not required on the labeling.

Essential oils don’t expire, but they do have a shelf life.  

Just like the cooking oils in your kitchen, essential oils go bad. While they don't have an expiration date,  they do have an estimated “best by” date, an expected shelf life.

Essential oils lose their therapeutic value over time as their chemistry changes. The process is called oxidization. Oxidized chemicals are not nice compounds – they tend to be slightly toxic and they increase the risk of negative side effects.

Once an essential oil starts breaking down, it's unsafe to use. Oxidized essential oils can irritate nasal membranes, cause dizziness, and cause other negative reactions. Over time they could possibly cause liver damage. 

Are your essential oils living beyond their shelf life? 

The nose knows best. The best way to detect oxidized essential oils is smell them. When you’ve been working with essential oils for a while your nose "knows" best... they just don't smell the same as a freshly opened bottle. They might smell "off", flat, or lost depth. They smell less potent than when the bottle was first opened.

Another sign is when an essential oil starts irritating your nose and eyes, makes your skin feel itchy and irritated, or causes a rash. If your reacting differently to an older essential oil, it's likely the oil has oxidized and is no longer effective or safe.

When it comes to staying safe with essential oils, a good offensive is the best defensive. Here's a few more tips to know if  your essential oils have "expired."

• The first step is knowing the estimated shelf life of each essential oil you buy. Essential oils generally last 1-8 years. Citrus oils, like lemon and orange, have the shortest life of 1-3 years, resinous oils like vetiver and myrrh last the longest, 6-8 years. Most essential oils are good for 3-5 years.
• Good aromatherapy suppliers will tell you an essential oil's shelf life AND track each batch of essential oil so you know when it was produced.  They will publish the date a batch of essential oils was produced and give it a batch number.  Really good companies include the batch number on the bottle. For example, lemon’s shelf life is 2 years. If you know your bottle of lemon was produced in 2019 and it’s now 2023—it’s no longer safe to use.
• While the shelf life starts after distillation, the biggest influence is when you first open the bottle. I recommend dating your bottle when you first open the bottle. Use permanent marker and put clear tape over it so it doesn't smudge. That way, even if you don't know the production date you'll at least have one date to reference.

Properly storing your essential oils significantly effect it's potency. Essential oils degrade in response to light, heat, and oxygen. Storing them in a cool, dark place will help maintain their quality.  A sunny kitchen counter or steamy bathroom may be a convenient, it's not the best place to store your oils. (And not in a car on a hot day.)

Essential oils also oxidize when they are exposed to oxygen.  This usually happen when a cap if left off the bottle (or not on tight) and when 1/2 the essential oils have been used, leaving air in the top half of the bottle. If you use your oils and then let it sit half empty for months, that air inside at the top of the bottle will cause oxidation. Or maybe the bottle has been mostly empty for around a year—meaning most of the bottle contains air-- that also causes oxidation and shortens an oil’s shelf life.  

It's important to note that oxidation does not vary by brand – it happens to every essential oil because of it's chemistry.

While you may not notice an older essential oil smelling different, your pet will.  Unfortunately, our pet's can't tell us it's changed. And since old, oxidized bottles of essential oils can be slightly toxic, and inhaling oxidized essential oils is not healthy for our  highly scent-sitive animal friends, we may need to say goodbye to those bottles.

What do you do with old, oxidized essential oils?

If you know they are losing potency, but aren't quite beyond their shelf life, you can add 2-4 drops to a dryer ball to freshen laundry, or to a vacuum bag to freshen a room. You can also use them for DIY cleaning, but wear gloves so they don't touch irritate your skin.

It’s easy to forget that essential oils are, in fact, oil and are flammable. When a bottle is well past it's shelf life, it should be disposed of like hazardous materials. When dealing with such small amounts it's tempting to pour them down the drain, but just like paint thinner and other household chemicals, essential oils should not be poured down drains. Whenever possible, bring them to your community’s hazardous waste disposal site.

Remember... when you buy essential oils make sure you know the the shelf life and any safety information of the essential oil you’re buying. And write the date you open the bottle on the label.  Essential oils will oxidize. The question isn’t IF, but WHEN.