For my aromatherapy certifications, I had to do many consultations and preparation of different sample products to be used by the client and reviewed by the course instructors. Much to my seeming shock, the feedback across the board was that in many cases I was using too much oil -- especially in rollers and/or too many different oils at the same time. As they said, “sometimes more oil is just more oil” meaning that it does not amplify the efficacy of a blend and in some cases - some oils you need more of and some oils you need less of and some oils need to be considered based upon safety information. A typical blend or synergy is made up of 3 to 5 essential oils. More can be used in certain situations, but again, we have to consider that “sometimes more oil is just more oil.”
Dilution ratios for 10ml rollers:When I first started making rollers, I just added 5-15 drops of each oil without considering why. I found recipes on Pinterest and through Google searches as well as essential oils Facebook groups. I didn’t think much of it at the time, but I was wasting soooooo much oil. In most rollers I was using upwards of 30 drops of oil! In some cases, that is fine for sleep and emotional support rollers, but for most rollers that was too much oil!!
What are dilution ratios?
They are based upon the number of drops needed factoring in the dilution ratio of 0.5% to 10% and above while also factoring in the amount of carrier oil used for 10ml rollers and containers from ½ an ounce to four ounces. Typically, the dilution ratio of 1-3% is pretty standard for non-acute considerations. It turns out that my 30 drops of oil in a roller bottle was way over 10% when in most cases it did not need to be.
It is recommended to start on a lower dilution ratio and adjust from there if the efficacy of the application isn’t producing the desired results.
The chart that I use comes from Tisserand & Young’s Essential Oil Safety book, which I highly recommend though it is a little pricey and sometimes over my head with science, but overall a great resource to have on hand.
There are many factors to consider regarding the dilution ratio selected for each roller. For infants over 6 months old and elderly individuals you may only need a few drops of oil total in a blend. Whereas for acute situations such as wound healing you may need to go anywhere from 10% - 50% of oil.
Please note that while most aromatherapists and schools do not recommend using essential oils on infants under 6 months old, many people do this safely for their children.
I have a chart that I keep updated located here:
Blending factors are judged on a scale from 1-10 and indicate how much of each oil to use in a blend. One being that the oil is more potent and you need less of it aromatically and ten meaning that it is less potent and you will need more of that oil. For example, if you are blending something with Lavender (blending factor 7) you may need to use 10 drops or more and if you are blending something with Cinnamon (blending factor 1) you may only need a couple drops.
This can be challenging to ascertain when using a pre-made blend with numerous oils in it. For instance a proprietary blend may contain Wintergreen (2), Peppermint (1), Helichrysum (5) and Clove (2). I would probably clock this one as having a blending factor of 3.
There is also a mathematical way to blend a synergy using blending factors as a basis for the blend.
Add up total blending factors
Divide the blending factor number total of each essential oil
To obtain the actual number multiply the percentage for each oil by the total number of drops needed
I am going to use Lavender (7), Lemon(6), and Peppermint (1) for 30 drops at a 5% dilution for a 1 ounce container. If you were making a roller, they are about ⅓ of an ounce.
Total blending factors = 14
Divide the individual blending factor by the total blending factor
Lavender: 7 divided by 14 = 0.5
Lemon: 6 divided by 14 = 0.42
Peppermint: 1 divided by 14 = 0.071
Multiply the percentage of each oil by 30 (which is the total number of drops needed for a blend with a 5% dilution)
Lavender: 0.5 x 30 = 15 drops
Lemon: 0.42 x 30 = 12.6 drops (round up to 13 drops)
Peppermint: 0.071 x 30 = 2.13
Once you get familiar with blending factors you can easily estimate the number of drops per oil without doing the mathematics.
Carrier oils also need to be factored into the equation as some are indicated for different purposes. For instance, if you were making an undereye roller, you would want to use argan or jojoba oil as opposed to fractionated coconut oil because they both have stronger benefits for the skin. If you are making a general purpose wellness roller, then FCO would be fine.
The lash serum story: recently someone posted about making a lash serum for someone using a mascara tube with a total of 30 drops of oil (Lavender, Cedarwood, and Rosemary) and the person said it really burned their eyes. OMG 30 drops of oils practically on the eyes??? At best, you really would only need under 10 drops total and more likely 2-3 and I would totally not use rosemary (there are different chemotypes of rosemary each with their own purposes). Also, when applying eyelash serum, I highly recommend using a small makeup brush to do so since you really want the serum to be applied where the lashes meet the eyelid.
Dermal Irritants and sensitizers: Some oils cause dermal irritation to the skin and mucous membranes.
Dermal irritants produces immediate irritation on the skin. This may present as blotching or redness and may be painful.
Avoid application of known dermal irritant essential oils on inflammatory and allergic skin conditions
Avoid application on open or damaged skin
Avoid undiluted application; always dilute known dermal irritants with vegetable oil or other carrier
If you suspect a client has sensitive skin, perform a skin patch test
Dermal Sensitization is the most common skin reaction to essential oils which presents as allergic contact dermatitis. On light-colored skin, contact dermatitis presents as a bright red rash, and on darker skin it appears as a dark blush.
There are two types of dermal sensitization - immediate hypersensitivity and delayed hypersensitivity (which happens upon subsequent use of the same oil.)
Photosensitization is a reaction to a substance applied to the skin that occurs only in the presence of UV light -- sunlight or artificial lights.
Mucous membrane irritants will produce a heating or drying effect on the mucous membranes of the mouth, eyes, nose, and reproductive organs.
Overuse of oils
Usage of the same oils for prolonged periods of time can cause you to either become immune to their therapeutic benefits or they can cause dermal irritation or sensitization.
PS. Think about the cost per drop: Essential oils are expensive and one should reflect upon overusing oils in a recipe and what that recipe costs you in wasted oils.
Frankincense - 30 cents per drop!
Lavender - 10 cents per drop!
Rose - $2.10 per drop!