Due to their different methods of extraction, there are always going to be similarities and differences between the aromatics produced via CO2 extraction and those produced by steam distillation.  What are they for Carrot Seed CO2 extract and Carrot Seed essential oil?

Common to both

Name: Carrot Seed Daucus carota (Wild Carrot)

Family:   Umbelliferae

Description:  This Annual or biennial herb has a small, inedible, tough whitish root, a much-branched stem with hairy leaves and umbels of white lacy flowers.  The top is often called Queen Anne’s Lace because of the lacey flowers.  It is native to Europe, Asia, and North Africa and naturalized in North America.

History/Folklore: The use of carrots as a medicinal herb dates back as early as 702 BC.  The earliest recorded use of carrot seed for medicinal purposes can be found in the ‘De medicina’ written by Aulus Cornelius Celsus between 25 BC and 50 AD.  It has been used in Chinese medicine to treat chronic dysentery and as an anthelmintic (destroy parasites).

Differences

Method of Extraction
CO2:
Carbon dioxide as the `solvent` to extract the viscous liquid from the seeds. Yield around 1.4%
Essential Oil:  The essential oil is steam distilled from the dried seeds. Yield around 0.4 – 0.8%.

Colour and Appearance
CO2:
 Light yellow to yellow liquid oil. (Kerkhof) Red mobile liquid.  (Burfield)
Essential Oil:
Pale yellow to amber.

Aroma
CO2:
  Very sweet lactonic, fruity odour. Dry out is sweet apricot, slightly creamy. (Burfield)
Essential Oil:
 Diffusive aldehydic almost peachy odour.  Dry-out is oily, dry aldehydic, with a hint of a hay note.  (Burfield) Warm, woody and a touch earthy.

Chemistry
CO2:
 CO2 select components include waxes, some fatty acids and up to 80% essential oil (containing Alcohols (30%); Monoterpenes (15%); Sesquiterpenes (15%).
Essential Oil:
  Esters (3%); Sesquiterpenes (16%); Monoterpenes (22%); Alcohols (25%); Phenols.

Cautions
CO2:
 Precautionary avoid during pregnancy & lactation.  (Kerkhof)
Essential Oil:
Hazards: May interfere with gestation.  Contraindications: All Routes: Pregnancy, breastfeeding. (Tisserand and Young)

Indications for Use

CO2:  Many skin conditions.  Maybe helpful for threatened elasticity to the skin.  Scars. Maturing and older skin.  Tired complexion. Eczema, psoriasis, rosacea, skin irritation. Cystitis. Liver and kidney support.
Essential Oil:
  Skincare: Dermatitis, eczema, oily skin, psoriasis, rashes, wrinkles, mature complexions (revitalizing and toning). Circulation and joints: Anemia, accumulation of toxins, arthritis, gout, edema, rheumatism. Digestive system: Anorexia, colic, indigestion, liver congestion.

Both the CO2 and the essential oil can be very helpful for anxiety, stress, and exhaustion.  Carrot seed oil is also a grounding oil.

You might also enjoy reading my blog on the Inner Nature of Carrot Seed as well as the article on Wrinkles and Aging of the Skin.

References
Tony Burfield, Natural Aromatic Materials – Odours & Origins, 2000
Ernst Guenther, The Essential Oil, Vol I-V, 1948 reprinted 1972
Madeline Kerkhof, CO2 Extracts in Aromatherapy, 2018
Tisserand and Young, 2nd Edition Essential Oil Safety, 2014