Which is a correct topical dilution guideline?

• A. Five drops per tablespoon of base oil
• B. One drop per teaspoon of base oil
• C. Ten drops per tablespoon of base oil
• D. Fifteen drops per tablespoon of base oil

Answer: (A)

For topical use, you want a dilution that is safe for skin while still giving some effect. Five drops of essential oil in a tablespoon (15 mL) of carrier oil gives about 0.25 mL of essential oil in 15 mL of base. That’s roughly 1.7% concentration. This falls into the common adult skin range for body application (about 1–2%), making it a balanced, widely recommended guideline for general topical blends like massage oils.

Higher numbers (like ten or fifteen drops per tablespoon) push the concentration into roughly 3–5%, which increases the risk of irritation for many people. A single drop per teaspoon would be around 1%, which is safer but less practical for a consistent massage blend in a single tablespoon volume.

So, five drops per tablespoon is a practical, safe, and commonly used guideline for moderate topical dilutions in adults.