How we source our essential-oil safety data

1. What this dataset covers

Every oil page, comparison, blend and tool on Dilutio is generated from a single structured dataset of 225 essential oils and aromatic materials. For each material we record its published maximum topical and facial dilution, any phototoxic (sunlight) limit, pregnancy, child, cat and dog suitability, and olfactory properties — perfumery note, aroma family, volatility and tenacity. The same values drive the visible tables, the schema.org data, and the Blend Analyzer, so what you read and what the tools compute never disagree.

2. Where the figures come from

The safety values reflect the levels commonly cited in the aromatherapy and fragrance-safety literature — principally Tisserand & Young’s Essential Oil Safety, IFRA (International Fragrance Association) standards, guidance from the National Association for Holistic Aromatherapy (NAHA), and, for animals, veterinary and poison-control sources such as the ASPCA. Where sources differ, we take the more conservative figure. These are widely used reference points, not a bespoke clinical study, and they are presented as educational information rather than a standard we certify.

3. What the dilution limits mean

• The figures are maximums for leave-on skin — ceilings, not targets. Everyday adult blends usually sit well below them (around 1–3% on the body, about 1% on the face).
• Body and face limits are listed separately, because facial skin is more sensitive and its ceiling is lower.
• Where an oil has no meaningful dermal restriction, it is shown as “No specific limit”, not as a high number — a high figure would read as a recommendation. The general demographic ceilings still apply.
• Children, pregnancy, and older or sensitive skin need lower dilutions than the adult figures shown.

4. Phototoxicity

A small, finite set of oils — almost all cold-pressed citrus — can make skin more sensitive to sunlight and UV after application, causing burns or lasting dark patches. For those oils we record a specific phototoxic limit; kept below it on leave-on skin they are fine, and rinse-off or diffused uses are not affected. Steam-distilled and FCF (bergapten-free) versions of the same citrus are not phototoxic. The full set is listed on the phototoxic oils page.

5. Pregnancy, children and pets

Suitability flags for pregnancy, children and pets are deliberately cautious and are meant only to steer you toward or away from an oil — not to approve a specific use. Cats in particular process many of these compounds slowly and are flagged conservatively. You can browse these as lists: oils generally considered suitable, and the oils to avoid, for pregnancy, children, cats and dogs.

6. What this is not

• It is educational information, not medical, veterinary, or cosmetic-regulatory advice.
• It is not a certification that any oil or blend is safe for you, your child, or your animal.
• It does not diagnose, treat, cure, or prevent any condition.
• It cannot account for your individual sensitivities — always patch-test, and consult a qualified professional for use during pregnancy, on children, around pets, or with a health condition.

7. Corrections

Found a figure you believe is wrong, or have a better-sourced reference? We take accuracy seriously — email support@dilut.io and we will review it.