Let’s Talk Safe Dilution

In my quest for safety info, safe dilution was the most difficult to address.  I knew that I could easily toss those who said to use oils neat out the door from my own experience.  On the other hand, there are many who toot the “1%, 2%, 3%” theory with nothing to back it up.  I need source material from credible sources after my blindly following the first set of people and becoming sensitized.

I bought Essential Oil Safety: A Guide for Health Care Professionals, 2nd Edition, by Robert Tisserand and Rodney Young and found that the “1%, 2%, 3%” theory is actually taken from a piece of knowledge in the book without using all of the knowledge the book offers.  They’ve taken a statement that is made about using a 1-5% safe dilution and run with it.  I joined some safety groups and lurked for a long time, gleaning tidbits here and there as I also read the book and combed through Tisserand’s blog.  My favorite safety group is Essential Oil Consumer Safety Advocates.

The book clarified a dilution safety question for me.  I’d had a major problem with the “1%, 2%, 3%” theory because 3% or even 5% doesn’t necessarily work for me with some oils.  Now, keep in mind that I’d been taught originally not to dilute, so my body has become habituated to certain oils (as well as sensitized to some of the gentlest oils).  It makes sense that 3% simply won’t do any good for an oil that my body expects more of.  I quit using those oils since they wouldn’t work at the dilutions I was seeing as “safe.”

Then, I ran across an explanatory passage that told the reader how Tisserand and Young created their  safe dilution for oils that are not known sensitizers, irritants, or phototoxic.  The dilutions for gentler oils in the book are based on a single use 30mL of oil diluted with a carrier.  They’re based on someone using the oil for a full body massage and at the max amount you can use of the oil in a given day.  They explain that, if you’re using a smaller amount, the dilution can be increased and give an example.  The formula to do this is: 30 divided by the amount of carrier you’re using, then multiply that by the max dermal dilution.  They give Dalmatian sage as an example for how to use their formula:

“For example, the maximum dermal use level for Dalmatian sage oil is 0.4%. But if only 5 mL (approximately 5 g) of a product containing this oil is used, the maximum concentration could be increased to 2.4%.”

That looks like this:  30/5=6, 6×0.4=2.4 . . . so if you’re using 5mL, you could dilute it to 2.4%.

Since I do not use oils for full body massage on myself, this was what I was looking for.  I create roller bottles that I use 2-3 times a day and just a few swipes at a time.  I have never even used 5mL in a single day and I don’t use tons of different oils every day.  Oh — and I rotate my oils to avoid habituation (very important).  So, I had this down, right?  If I wanted lavender in a roller bottle, I used the formula and could use as much as 30% in a 5mL roller bottle (30/5=6, 6×5=30).  30% actually seemed a little high to me, so I stuck with 20%.  I don’t care what the max on the formula is, if it’s more than 20%, I always stay at a max of 20% dilution.  If it’s under 20%, I go with the final solution in the formula.  If it’s a sensitizer, irritant, or is phototoxic, I do not use the formula.

Just when I thought I had it, someone in the above-mentioned group made a statement about mild oils (like lavender) needing to be at most 10%.

Huh?  My world fell apart.

I re-read info about it in the book, reworked the formula and example every way I could think of to see if any other way gave the same result.  None did.  So, I posted in the group, questioning if I’d read it wrong, and tagged Robert Tisserand for clarification — yes, he’s a member of the group.  While waiting for him to see the tag and hopefully give a response, I had a couple of people talk to me through messages and tell me that I did, indeed have it wrong.  I read what they had to say, discussed with them . . . and waited.  This morning, I got up to my answer:

He said:  “You are totally right Dedi Keenan Thorne, if the maximum dilution is for a systemic toxicity (neurotoxicity, as in sage oil, carcinogens etc). But if it’s for any kind of skin reaction, as you say, the dilution applies whatever. This is because systemic toxicity is based on the amount that gets into the body, which varies with the total quantity of oil applied as well as the dilution, but skin reactions depend only on the dilution of the oil applied to the skin.”

He goes on to say:  “You still have to account for general safety guidelines and common sense. Table 4.5 [he’s referring to a table in the book] shows age-related maximums, going up to 5% for an adult for whole-body application. In some cases this can be exceeded for local application but I don’t have rules for that.”

Yay!  Right?!  Wait!  No.

Now I’ve had two people messaging me and telling me that my safe dilution was way off.


I do not want to be unsafe nor impart unsafe information.  So, I turn to another very respected source, Sylla Sheppard-Hanger.  Sylla runs the Atlantic Institute of Aromatherapy and I have full faith that she’s going to guide safely.  As a matter of fact, she’s incredibly worried about the unsafe practices going on.  I highly suggest that you read through the school’s blog for great info and follow their Facebook page for good info from other sources.

I approached Sylla through a private message, in case she didn’t agree with Tisserand.  I certainly did not want to have drama started in a group.  I just wanted more than one expert’s opinion.  Since she’s also a member of the group, she read through the post and its comments and came back with, “go by what he says!!” — and gave me permission to quote her.  Thanks, Sylla!

If you’d like to read through it all, you can join the group and see the post here.  Fair warning:  Drama won’t be tolerated.  Read the group guidelines and follow them — don’t ask for oil prescriptions, they’re not doctors and will not act as if they are (i.e.: “What can I use for ADHD”).  Do ask about safe practices.  Do use the search feature because there’s a ton of great info in old posts.  Don’t add people to the group, they must add themselves if they want to join because bad things have happened with people who didn’t want to hear about safety and were added by well-meaning friends.

NOW, I’m comfy with giving you the information I’ve learned.  It was a long road to get here and I know many of you have waited for a long time.  Thanks for your patience and understanding.  Lots of you have asked for this information.

Before I give you a list of safe dilution ranges, you need to understand that what you use depends on your life or the life of the person using the oil.  There aren’t hard, fast rules that can apply to everyone in most aromatherapy cases.  Thought and care are going to be required.

Do you diffuse a lot of an oil?  Then, heaven forbid, use common sense and don’t use max dilution topically!  Do you use a lot of different oils topically?  Again, stay well below max guidelines!  Do you take a lot of medication?  Then reign in those common sense gems; stay well under max dilution and don’t overload your liver.  Are you suffering from chronic sickness?  Stay well under max dilution (we suggest you stay with safe dilution for older children)!  Are you on certain medications?  Read our safety info on each oil.  If they’re not to be used with certain medications (or pregnant/breastfeeding women), it’s stated there and there’s no safe dilution for you to use those oils!

I do not use Tisserand’s conversion formula with dilutions for babies/kids.  I don’t suggest you do either.  And, if you read his quotes above, he doesn’t make rules for changing those.  It’s just best to stay within his safe dilution guidelines for little ones.

If you see only a very low percentage, it’s an oil that is a sensitizer, an irritant, or is phototoxic — or it’s a dilution for youngsters.  Never go any higher than what you see for max, no matter how much or how little carrier you use.  Keep in mind that these were already converted for 5mL.  Don’t attempt to convert again.

This is not a comprehensive list.  It’s a list of the oils we carry at the moment.  If you have an oil that is not on this list and would like to know a safe range, contact us and we’ll be more than happy to help you be safe.  Safety is foremost for us, whether you’re using our oils or oils from another company.

Also . . . always rotate oils.  If you use one for as long as 10 – 14 days, then you need to start using another that has the same benefits you’re looking for.  If you don’t you will habituate and it will quit working for you.  We’ll discuss that in another post.

Keep in mind that the adult max amounts are figured for 5mL of carrier oil.  I actually recommend that you use no more than 2mL in a day, especially if you use other oils.   You can also download a pdf file Dilution Safety.

Don’t forget that the oils and age groups that can be safely converted already have been converted.  Do not use more than the max you see in this list!  If you don’t see a safe dilution listed, that oil is not recommended for that age group!

Safe Dilution Chart

Safe Dilution ChartClick the chart to open a much larger picture of the safe dilution chart. The original makes this page load too slowly.

For educational purposes only. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Links to outside sources open in a new tab or window and are often affiliate links to items we use and trust in.