Interesting, D-Limonene is a natural solvent, smells good and easily available. I use to use it in the shed for cleaning surfaces just because it smelled good. Found in citrus fruit obviously. I should add essential oils like mandarin, orange are very high in D-Limonene. Infact I think the grapefruit essential oil, iirc, is like 95% D-Limonene.
Heard of people using a few drops of grapefruit essential oil in vegetable capsules and quickly swallowing them (before the capsule starts to fall apart) to ease nausea when partaking in trip related activities. (The reason for the capsule use is that even a couple drops of the concentrate can cause mouth and throat irritation).