CCAP CCAP Essential Oil Chemistry 2 — Questions and Answers
Question 1: Monoterpenes such as limonene and pinene are volatile at room temperature primarily because they:
- Contain heavy metal ions
- Have low molecular weight and high vapor pressure (Correct answer)
- Are water-soluble compounds
- Form strong covalent bonds with proteins
Correct answer: Have low molecular weight and high vapor pressure
Monoterpenes evaporate quickly due to their small molecular size and high vapor pressure, which is why they are top notes in aromatherapy blends.
Question 2: Which process is used to extract most steam-distilled essential oils from plant material?
- Cold expression
- Solvent extraction
- CO2 hypercritical extraction
- Steam or hydro-distillation (Correct answer)
Correct answer: Steam or hydro-distillation
Steam or hydro-distillation passes steam through plant material, volatilizing aromatic constituents that are then condensed and separated from the hydrosol.
Question 3: Furanocoumarins in bergamot essential oil (e.g., bergapten) are clinically significant because they cause:
- Photosensitivity and phototoxicity when skin is exposed to UV light (Correct answer)
- Immediate allergic contact dermatitis in all patients
- Sedative effects when inhaled
- Increased absorption of other topical medications
Correct answer: Photosensitivity and phototoxicity when skin is exposed to UV light
Furanocoumarins are phototoxic compounds that react with UV radiation to cause skin burns, hyperpigmentation, or blistering — requiring a bergapten-free version for topical use.
Question 4: A clinical aromatherapist reviews a GC/MS report showing an unusually high percentage of an unexpected constituent. This most likely indicates:
- Superior therapeutic potency
- Natural seasonal variation only
- Possible adulteration or contamination of the oil (Correct answer)
- A new chemotype of the plant
Correct answer: Possible adulteration or contamination of the oil
Unexpected high percentages of atypical constituents on a GC/MS report are a key indicator of adulteration — the addition of synthetic or foreign substances to the essential oil.
Question 5: What is a 'chemotype' (ct.) in essential oil terminology?
- A synthetic chemical added to essential oils
- A variant of the same plant species with a distinctly different chemical profile (Correct answer)
- A grading system for organic certification
- A term for essential oils extracted by CO2
Correct answer: A variant of the same plant species with a distinctly different chemical profile
A chemotype refers to plants of the same species grown in different regions or conditions that produce essential oils with significantly different dominant chemical constituents.
Question 6: Ketones in essential oils, such as camphor and pulegone, require special caution because they can be:
- Too gentle for clinical use
- Neurotoxic and potentially abortifacient at high doses (Correct answer)
- Highly water-soluble and poorly absorbed
- Primarily irritating only to mucous membranes
Correct answer: Neurotoxic and potentially abortifacient at high doses
Ketones can be neurotoxic and some (like pulegone in pennyroyal) are abortifacient, requiring careful dosing and avoidance in pregnancy, infants, and seizure disorders.
CCAP CCAP Essential Oil Chemistry 2
Monoterpenes such as limonene and pinene are volatile at room temperature primarily because they: